-
International Journal of Molecular... Mar 2021Acrylamide is a commonly used industrial chemical that is known to be neurotoxic to mammals. However, its developmental toxicity is rarely assessed in mammalian models...
Acrylamide is a commonly used industrial chemical that is known to be neurotoxic to mammals. However, its developmental toxicity is rarely assessed in mammalian models because of the cost and complexity involved. We used zebrafish to assess the neurotoxicity, developmental and behavioral toxicity of acrylamide. At 6 h post fertilization, zebrafish embryos were exposed to four concentrations of acrylamide (10, 30, 100, or 300 mg/L) in a medium for 114 h. Acrylamide caused developmental toxicity characterized by yolk retention, scoliosis, swim bladder deficiency, and curvature of the body. Acrylamide also impaired locomotor activity, which was measured as swimming speed and distance traveled. In addition, treatment with 100 mg/L acrylamide shortened the width of the brain and spinal cord, indicating neuronal toxicity. In summary, acrylamide induces developmental toxicity and neurotoxicity in zebrafish. This can be used to study acrylamide neurotoxicity in a rapid and cost-efficient manner.
Topics: Acrylamide; Air Sacs; Animals; Animals, Genetically Modified; Disease Models, Animal; Embryo, Nonmammalian; Embryonic Development; Neurotoxicity Syndromes; Scoliosis; Swimming; Zebrafish
PubMed: 33805345
DOI: 10.3390/ijms22073518 -
Philosophical Transactions of the Royal... Mar 2020The Archosauria are a highly successful group of vertebrates, and their evolution is marked by the appearance of diverse respiratory and metabolic strategies. This... (Review)
Review
The Archosauria are a highly successful group of vertebrates, and their evolution is marked by the appearance of diverse respiratory and metabolic strategies. This review examines respiratory function in living and fossil archosaurs, focusing on the anatomy and biomechanics of the respiratory system, and their physiological consequences. The first archosaurs shared a heterogeneously partitioned parabronchial lung with unidirectional air flow; from this common ancestral lung morphology, we trace the diverging respiratory designs of bird- and crocodilian-line archosaurs. We review the latest evidence of osteological correlates for lung structure and the presence and distribution of accessory air sacs, with a focus on the evolution of the avian lung-air sac system and the functional separation of gas exchange and ventilation. In addition, we discuss the evolution of ventilation mechanics across archosaurs, citing new biomechanical data from extant taxa and how this informs our reconstructions of fossils. This improved understanding of respiratory form and function should help to reconstruct key physiological parameters in fossil taxa. We highlight key events in archosaur evolution where respiratory physiology likely played a major role, such as their radiation at a time of relative hypoxia following the Permo-Triassic mass extinction, and their evolution of elevated metabolic rates. This article is part of the theme issue 'Vertebrate palaeophysiology'.
Topics: Alligators and Crocodiles; Animals; Biological Evolution; Birds; Fossils; Reptiles; Respiration
PubMed: 31928195
DOI: 10.1098/rstb.2019.0140 -
International Journal For Parasitology.... Dec 2022Helminths are not usually considered important pathogens for birds of prey. There is a single published report of mortality in raptors due to an air sac trematode...
Helminths are not usually considered important pathogens for birds of prey. There is a single published report of mortality in raptors due to an air sac trematode infection. We report a well-documented death case from massive infection by an air sac trematode of the family Cyclocoelidae in a wild-caught, juvenile male Snail Kite () in Ecuador. The necropsy of a Snail Kite revealed more than 200 trematodes among air sacs, lungs, heart, gizzard, proventriculus, and liver. Within air sacs and lungs, mature flukes were associated with sacculitis, bronchitis, pneumonia, and atelectasis. Using an integrative taxonomic approach with morphological and molecular data, we identified the parasites as (Trematoda: Cyclocoelidae: Ophthalmophaginae). This case provides the first evidence for the pathologic presence of air sac trematodes associated with morbidity in birds of prey in South America. Our results suggest that cyclocoelids may cause debilitation and significant clinical lesions in birds of prey, with potentially fatal consequences.
PubMed: 36157127
DOI: 10.1016/j.ijppaw.2022.09.001 -
International Journal of Molecular... Jul 2018The acquisition of invasive properties preceding tumor metastasis is critical for cancer progression. This phenomenon may result from mutagenic disruption of typical... (Review)
Review
The acquisition of invasive properties preceding tumor metastasis is critical for cancer progression. This phenomenon may result from mutagenic disruption of typical cell function, but recent evidence suggests that cancer cells frequently co-opt normal developmental programs to facilitate invasion as well. The signaling cascades that have been implicated present an obstacle to identifying effective therapeutic targets because of their complex nature and modulatory capacity through crosstalk with other pathways. Substantial efforts have been made to study invasive behavior during organogenesis in several organisms, but another model found in has not been thoroughly explored. The air sac primordium (ASP) appears to be a suitable candidate for investigating the genes and morphogens required for invasion due to the distinct overlap in the events that occur during its normal growth and the development of metastatic tumor cells. Among these events are the conversion of larval cells in the trachea into a population of mitotically active cells, reduced cell⁻cell contact along the leading edge of the ASP, and remodeling of the extracellular matrix (ECM) that surrounds the structure. Here, we summarize the development of ASPs and invasive behavior observed therein.
Topics: Air Sacs; Animals; Drosophila melanogaster; Gene Expression Regulation, Developmental; Humans; Neoplasm Invasiveness; Neoplasms; Organogenesis; Signal Transduction; Trachea
PubMed: 30018198
DOI: 10.3390/ijms19072074 -
International Journal For Parasitology.... Aug 2023Major climatic changes in conjunction with animal movement may be associated with the spread of parasites and their vectors into new populations, with potentially...
Major climatic changes in conjunction with animal movement may be associated with the spread of parasites and their vectors into new populations, with potentially important consequences for population persistence. Parasites can evolve to adapt to unsuitable ecological conditions and take up refuge within new host species, with consequences for the population growth of the new host species. One parasite species that has likely been increasing its geographic range, and potentially infecting new hosts, is the recently described air sac nematode , in great tits () in Slovakia. In this study, we screened wild birds for potential air sac nematode infection in a woodland area of southern Germany. We identified four additional host species: Eurasian nuthatch, great spotted woodpecker, greenfinch and robin. As infection by this group of nematodes can be highly pathogenic, we recommend further investigation into its potential risk to these populations.
PubMed: 37252653
DOI: 10.1016/j.ijppaw.2023.05.004 -
Environmental Health Perspectives Apr 1984The pulmonary macrophagic system is critical to the defense of the lung, keeping the alveoli clean and sterile and responding on demand with an adaptive outpouring of... (Review)
Review
The pulmonary macrophagic system is critical to the defense of the lung, keeping the alveoli clean and sterile and responding on demand with an adaptive outpouring of new cells into the air sacs. Under basal conditions alveolar macrophages, in common with other mononuclear phagocytes, are derived from the bone marrow. A population of macrophage precursors within the pulmonary interstitium provides a reserve pool capable of proliferation and delivery of phagocytes in response to unusually heavy loads of inhaled particles. This reserve system also produces macrophages when monocytic precursors in the bone marrow are depleted by diseases such as leukemia. The alveolar macrophage is destined to ingest particulate matter and to be eliminated along the mucociliary pathway; clearance by lymphatics is of minor importance and macrophages probably do not recross the alveolar epithelium to reach the pulmonary interstitial compartment. Although the protective role of the macrophage is dominant, this cell may participate, directly or indirectly, in the genesis of two major groups of chronic pulmonary disease, interstitial fibrosis and emphysema. Such inappropriate responses involve interactions with fibroblastic cells and tissue injury initiated by proteases secreted by the macrophage.
Topics: Animals; Fibroblasts; Humans; Kinetics; Lung; Lung Diseases; Lysosomes; Macrophages; Phagocytosis; Pulmonary Alveoli
PubMed: 6376105
DOI: 10.1289/ehp.8455327 -
The Journal of Veterinary Medical... Mar 2022Captive penguins with respiratory diseases exhibit advanced pathological conditions upon the appearance of clinical signs. Therefore, the successful treatment of...
Captive penguins with respiratory diseases exhibit advanced pathological conditions upon the appearance of clinical signs. Therefore, the successful treatment of respiratory diseases remains difficult after the onset of clinical signs, leading to high mortality rates. In this study, we measured air sac volume using computed tomography (CT) to evaluate the respiratory condition of penguins. In a regular quarterly health checkup, blood samples were collected from 45 penguins housed at an aquarium in Hokkaido, Japan. A total of 12 penguins with abnormal blood parameters underwent CT. The air sac volumes were calculated in three-dimensional CT, and the scatter plots of the air sac volumes and body weights were analyzed. No correlation was found between the air sac volume and body weight in both the gentoo and king penguins. Two gentoo penguins with infiltration and one king penguin with multiple nodules on CT were tentatively diagnosed with aspergillosis and treated with oral administration of itraconazole. Follow-up CT examination was performed until the outcome: healed or died. The mean air sac volumes of the two gentoo penguins, which recovered after treatment, increased from 273.9 and 329.0 cm before healing to 449.0 and 424.6 cm after healing, respectively. Meanwhile, the air sac volume of the king penguin, which subsequently died, decreased from 1,556.9 to 920.6 cm despite treatment. Changes of the air sac volume in the same individual could be useful for evaluating the respiratory condition of penguins.
Topics: Air Sacs; Animals; Aspergillosis; Itraconazole; Spheniscidae; Tomography, X-Ray Computed
PubMed: 35046242
DOI: 10.1292/jvms.21-0619 -
Current Biology : CB Feb 2022The freshwater aquatic larvae of the Chaoborus midge are the world's only truly planktonic insects, regulating their buoyancy using two pairs of internal air-filled...
The freshwater aquatic larvae of the Chaoborus midge are the world's only truly planktonic insects, regulating their buoyancy using two pairs of internal air-filled sacs, one in the thorax and the other in the seventh abdominal segment. In 1911, August Krogh demonstrated the larvae's ability to control their buoyancy by exposing them to an increase in hydrostatic pressure. However, how these insects control the volume of their air-sacs has remained a mystery. Gas is not secreted into the air-sacs, as the luminal gas composition is always the same as that dissolved in the surrounding water. Instead, the air-sac wall was thought to play some role. Here we reveal that bands of resilin in the air-sac's wall are responsible for the changes in volume. These bands expand and contract in response to changes in pH generated by an endothelium that envelops the air-sac. Vacuolar type H V-ATPase (VHA) in the endothelium acidifies and shrinks the air-sac, while alkalinization and expansion are regulated by the cyclic adenosine monophosphate signal transduction pathway. Thus, Chaoborus air-sacs function as mechanochemical engines, transforming pH changes into mechanical work against hydrostatic pressure. As the resilin bands interlaminate with bands of cuticle, changes in resilin volume are constrained to a single direction along the air-sac's longitudinal axis. This makes the air-sac functionally equivalent to a cross-striated pH muscle and demonstrates a unique biological role for resilin as an active structural element.
Topics: Animals; Fresh Water; Hydrogen-Ion Concentration; Larva; Water
PubMed: 35081331
DOI: 10.1016/j.cub.2022.01.018 -
Anatomical Record (Hoboken, N.J. : 2007) Jan 2023Avian respiratory systems are comprised of rigid lungs connected to a hierarchically organized network of large, regional air sacs, and small diverticula that branch... (Review)
Review
Avian respiratory systems are comprised of rigid lungs connected to a hierarchically organized network of large, regional air sacs, and small diverticula that branch from them. Paramedullary diverticula are those that rest in contact with the spinal cord, and frequently invade the vertebral canal. Here, we review the historical study of these structures and provide the most diverse survey to date of paramedullary diverticula in Aves, consisting of observations from 29 taxa and 17 major clades. These extensions of the respiratory system are present in nearly all birds included in the study, with the exception of falconiforms, gaviiforms, podicipediforms, and piciforms. When present, they share connections most commonly with the intertransverse and supravertebral diverticula, but also sometimes with diverticula arising directly from the lungs and other small, more posterior diverticula. Additionally, we observed much greater morphological diversity of paramedullary airways than previously known. These diverticula may be present as one to four separate tubes (dorsal, lateral, or ventral to the spinal cord), or as a single large structure that partially or wholly encircles the spinal cord. Across taxa, paramedullary diverticula are largest and most frequently present in the cervical region, becoming smaller and increasingly absent moving posteriorly. Finally, we observe two osteological correlates of paramedullary diverticula (pneumatic foramina and pocked texturing inside the vertebral canal) that can be used to infer the presence of these structures in extinct taxa with similar respiratory systems.
Topics: Osteology; Tomography
PubMed: 35338748
DOI: 10.1002/ar.24923