注釈付き翻訳「水生、泥生および陸生ハゼ類の呼吸に関する形態学および生理学」Elfriede Schöttle (1931)著

The original German paper written by Dr. Elfriede Schöttle was published by Akademische Verlagsgesellshaft, M. B. H., Leipzig in 1931 as follows; Schöttle, E. (1931) Morphologie und Physiologie der Atmung bei wasser-, schlamm- und landlebenden Gobiiformes. Zeitschrift für Wissenschaftliche Zoologie, 140, 1–114

EFFECTS OF CO 2 OCEAN SEQUESTRATION ON MARINE FISH

ABSTRACT Ocean sequestration of CO 2 has been proposed as a possible measure to retard the increasing rate of the atmospheric CO 2 concentration. Since some negative impacts on marine animals and ecosystems are likely to ensue, we must carefully investigate biological effects of ocean CO 2 sequestration before embarking on this mitigation practice. Considering the expected depths for CO 2 ocean sequestration (> 1,000 m), it is desirable to use deep-sea animals for the experimental assessment of CO 2 ocean sequestration. In addition, experimental protocols preferably mimic environmental conditions at the releasing site: CO 2 concentrations vary due to mixing with surrounding seawater at low temperatures (0-2 °C) and under high pressures. This paper describes our recent experiments to elucidate the effects of high CO 2 on marine fishes. A deep-sea fish Careproctus trachysoma (habitat depth 400-800 m) can be captured alive and be used for in vivo CO 2 exposure experiments. 100% mortality occurred when the fish was exposed to seawater equilibrated with a gas mixture containing 3% CO 2 conditions at 2 °C within 48 h, whereas mortality was never observed when shallow-water fishes (Mustelus manazo, Paralichthys olivaceus and Seriola quinqueradiata) were tested under the same CO 2 conditions but at higher temperatures (17-20 °C). It is currently not clear whether this difference in mortality is due to often presumed high susceptibility of deepsea organisms to environmental perturbations. Subsequent experiments demonstrated that low water temperature accelerates mortality by CO 2 exposure. Thus, half lethal time decreased from 105h to only 5 h when water temperature was decreased from 26 °C to 20 °C (CO 2 8.5%, Sillago parvisquamis). Therefore, the high CO 2 susceptibility of C. trachysoma could be solely due to low water temperature. Temporally varying CO 2 conditions resulted in markedly different mortality patterns when compare with mortality recorded under constant CO 2 conditions. Step-wise increases in ambient CO 2 resulted in much lower mortalities than under one-step increases to the same CO 2 levels. Further, a sudden drop of CO 2 from 9-10% CO 2 to air level (0.038%) killed all the surviving fish within a few minutes

Ecology of the Australian mudskipper Periophthalmus minutus, an amphibious fish inhabiting a mudflat in the highest intertidal zone

A population of Periophthalmus minutus inhabiting a mudflat in the highest intertidal zone in Darwin was investigated for surface activity, feeding and reproduction in relation to environmental conditions in the dry (August) and wet (February) seasons. On days with tidal inundation, the fish were diurnally active on the exposed mudflat surface at low tide, but retreated into burrows during daytime inundation and at night. Temperatures above 40°C and heavy precipitation suppressed the daytime surface activity of the fish. During neap tides, the mudflat remained uncovered by the tide for nine days in both seasons. The fish confined themselves in burrows without ingested food throughout the nine-day period in August, but they remained active on the mudflat surface and kept foraging in February. The salinity of burrow water during the nine-day emersion was extremely high (72±6 psu, mean±s.d.) in August, but lower (46±9), though still higher than the open seawater value (34), in February. The burrows were J-shaped in February, but were straight (with no upturn) in August. Fertilised eggs were collected from the upturned portionof the burrow, and hatched upon submersion. Juveniles occurred in water pools on the mudflat surface in March

Acute CO2 tolerance limits of juveniles of three marine invertebrates, Sepia lycidas, Sepioteuthis lessoniana, and Marsupenaeus japonicus

CO2 ocean storage is proposed as a possible measure to mitigate climate changes caused by increasing atmospheric concentrations of the gas. The feasibility of the measure has been intensively investigated, yet its biological impact on marine animals is still largely unknown. We investigated the acute CO2 tolerance of juveniles of three marine invertebrates; the cuttlefish, Sepia lycidas, the squid, Sepioteuthis lessoniana, and the prawn, Marsupenaeus japonicus. Median tolerance limits of CO2 were 8.4% (24 h) for the cuttlefish, 5.9% (24 h) and 3.8% (48 h) for the squid and 14.3% (72 h) for the prawn. Comparison of these and previously reported data suggests an inverse relationship between O2 requirement and CO2 tolerance among marine animals

A fatal case of acute exacerbation of interstitial lung disease in a patient with rheumatoid arthritis during treatment with tocilizumab.

A 68-year-old man, who was a patient with established rheumatoid arthritis (RA) with RA-associated interstitial lung disease (RA-ILD) and pulmonary emphysema, began taking tocilizumab. Subsequently, he developed dyspnea parallel to improvement of RA. At 10 months after the administration of tocilizumab, he was urgently admitted because of exacerbation of ILD. He died despite receiving steroid pulse therapy and antibiotic therapy on a respirator. This is the first case report to describe the exacerbation of ILD during treatment with tocilizumab in the postmarketing surveillance (PMS) period

Direct evidence for aerial egg deposition in the burrows of the Malaysian mudskipper, Periophthalmodon schlosseri

The presence of mudskipper eggs in an air-filled chamber was confirmed by direct endoscopic observation of intact burrows of Periophthalmodon schlosseri in a mudflat in Penang, Malaysia. For all five burrows from which video images of egg chambers were successfully obtained, the presence of air was unequivocally demonstrated by the existence of an air-water interface inside the chambers. Of these burrows, eggs were found in two, but not in the others. Eggs were laid uniformly in a monolayer on the inner top surface of the chamber. The much brighter color of the surface mud of the egg chambers than the surrounding mud, irrespective of the presence or absence of the eggs, suggested that the surface mud had been oxidized by deposited air

Effects of high CO2 seawater on the copepod (Acartia tsuensis) through all life stages and subsequent generations

We studied the effects of exposure to seawater equilibrated with CO2-enriched air (CO2 2380 ppm) from eggs to maturity and over two subsequent generations on the copepod Acartia tsuensis. Compared to the control (CO2 380 ppm), high CO2 exposure through all life stages of the 1st generation copepods did not significantly affect survival, body size or developmental speed. Egg production and hatching rates were also not significantly different between the initial generation of females exposed to high CO2 and the 1st and 2nd generation females developed from eggs to maturity in high CO2. Thus, the copepods appear more tolerant to increased CO2 than other marine organisms previously investigated for CO2 tolerance (i.e., sea urchins and bivalves). However, the crucial importance of copepods in marine ecosystems requires thorough evaluation of the overall impacts of marine environmental changes predicted to occur with increased CO2 concentrations, i.e., increased temperature, enhanced UV irradiation, and changes in the community structure and nutritional value of phytoplankton

Identification and distribution of neuronal nitric oxide synthase and neurochemical markers in the neuroepithelial cells of the gill and the skin in the giant mudskipper, Periophthalmodon schlosseri

Mudskippers are amphibious fishes living in mudflats and mangroves. These fishes hold air in their large buccopharyngeal-opercular cavities where respiratory gas exchange takes place via the gills and higher vascularized epithelium lining the cavities and also the skin epidermis. Although aerial ventilation response to changes in ambient gas concentration has been studied in mudskippers, the localization and distribution of respiratory chemoreceptors, their neurochemical coding and function as well as physiological evidence for the gill or skin as site for O2 and CO2 sensing are currently not known. In the present study we assessed the distribution of serotonin, acetylcholine, catecholamines and nitric oxide in the neuroepithelial cells (NECs) of the mudskipper gill and skin epithelium using immunohistochemistry and confocal microscopy. Colocalization studies showed that 5-HT is coexpressed with nNOS, Na+/K+-ATPase, TH and VAChT; nNOS is coexpressed with Na+/K+-ATPase and TH in the skin. In the gill 5-HT is coexpressed with nNOS and VAhHT and nNOS is coexpressed with Na+/K+-ATPase and TH. Acetylcholine is also expressed in chain and proximal neurons projecting to the efferent filament artery and branchial smooth muscle. The serotonergic cells c labeled with VAChT, nNOS and TH, thus indicating the presence of NEC populations and the possibility that these neurotransmitters (other than serotonin) may act as primary transmitters in the hypoxic reflex in fish gills. Immunolabeling with TH antibodies revealed that NECs in the gill and the skin are innervated by catecholaminergic nerves, thus suggesting that these cells are involved in a central control of branchial functions through their relationships with the sympathetic branchial nervous system. The Na+/K+-ATPase in mitochondria-rich cells (MRCs), which are most concentrated in the gill lamellar epithelium, is colabeled with nNOS and associated with TH nerve terminals. TH-immunopositive fine varicosities were also associated with the numerous capillaries in the skin surface and the layers of the swollen cells. Based on the often hypercapnic and hypoxic habitat of the mudskippers, these fishes may represent an attractive model for pursuing studies on O2 and CO2 sensing due to the air-breathing that increases the importance of acid/base regulation and the O2-related drive including the function of gasotransmitters such as nitric oxide that has an inhibitory (regulatory) function in ionoregulation.This research was supported by project PAN LAB PONA3_00166. The authors would like to thank Michał Ignaszewski (TDT) for his kind help in statistical analysis

Expression of the Antimicrobial Peptide Piscidin 1 and Neuropeptides in Fish Gill and Skin: A Potential Participation in Neuro-Immune Interaction

Antimicrobial peptides (AMPs) are found widespread in nature and possess antimicrobial and immunomodulatory activities. Due to their multifunctional properties, these peptides are a focus of growing body of interest and have been characterized in several fish species. Due to their similarities in amino-acid composition and amphipathic design, it has been suggested that neuropeptides may be directly involved in the innate immune response against pathogen intruders. In this review, we report the molecular characterization of the fish-specific AMP piscidin1, the production of an antibody raised against this peptide and the immunohistochemical identification of this peptide and enkephalins in the neuroepithelial cells (NECs) in the gill of several teleost fish species living in different habitats. In spite of the abundant literature on Piscidin1, the biological role of this peptide in fish visceral organs remains poorly explored, as well as the role of the neuropeptides in neuroimmune interaction in fish. The NECs, by their role as sensors of hypoxia changes in the external environments, in combination with their endocrine nature and secretion of immunomodulatory substances would influence various types of immune cells that contain piscidin, such as mast cells and eosinophils, both showing interaction with the nervous system. The discovery of piscidins in the gill and skin, their diversity and their role in the regulation of immune response will lead to better selection of these immunomodulatory molecules as drug targets to retain antimicrobial barrier function and for aquaculture therapy in the future.Expression of the Antimicrobial Peptide Piscidin 1 and Neuropeptides in Fish Gill and Skin: A Potential Participation in Neuro-Immune InteractionpublishedVersio

Respiratory vasculatures of the intertidal air-breathing eel goby, Odontamblyopus lacepedii (Gobiidae: Amblyopinae)

Lacking a propensity to emerge over the mud surface, the eel goby, Odontamblyopus lacepedii, survives low tide periods by continuously breathing air in burrows filled with hypoxic water. As with most marine air-breathing fishes, O. lacepedii does not possess an accessory air-breathing organ, but holds air in the buccal-opercular cavity. The present study aimed to clarify how the respiratory vasculature has been modified in this facultative air-breathing fish. Results showed that the gills apparently lacked structural modifications for air breathing, whereas the inner epithelia of the opercula were richly vascularized. Comparison with two sympatric gobies revealed that the density of blood capillaries within 10μm from the inner opercular epithelial surface in O. lacepedii (14.5 ± 3.0 capillaries mm-1; mean ± s.d., n = 3) was significantly higher than in the aquatic non-air-breathing Acanthogobius hasta (0.0 ± 0.0) but significantly lower than in the amphibious air-breathing mudskipper, Periophthalmus modestus (59.1 ± 8.5). The opercular capillary bed was supplied predominantly by the 1st efferent branchial arteries (EBA1) and drained by the opercular veins, which open into the anterior cardinal vein. Deep invaginations at the distal end of the EBA1 and the junction with EBA2 are suggestive of blood flow regulatory sites during breath-holding and apnoeic periods. It remains to be investigated how blood flow through the gills is maintained during breath holding when the buccal-opercular cavity is filled with air