The Exchange of Labelled Sodium in the Larva of Aedes Aegypti L

1954 ◽  
Vol 31 (3) ◽  
pp. 386-401 ◽  
Author(s):  
JOHN E. TREHERNE
Keyword(s):  
Aedes Aegypti ◽  
Body Surface ◽  
External Medium ◽  
Whole Body ◽  
Effect Of Temperature ◽  
Potassium Ions ◽  
Distilled Water ◽  
General Body ◽  
Anal Papillae

1. The exchange of labelled sodium between the external medium and the haemolymph and whole body has been investigated in the larva of Aedes aegypti. The time for half exchange was of the order of 62 hr. 2. It was found that most of the exchange of labelled sodium occurred through the anal papillae, although smaller amounts enter the haemolymph through the gut and general body surface. Transfer constants have been used to describe the resultant turnover of labelled sodium in the whole system. 3. The rate of uptake of sodium was independent of the external concentrations used in these experiments. 4. Potassium ions do not compete with sodium for uptake, which suggests that separate mechanisms are responsible for the accumulation of these two ions. 5. Larvae were able to retain the sodium in the haemolymph, with relatively little loss, in glass-distilled water. 6. The effect of temperature on the rate of uptake of labelled sodium has been investigated.

scholarly journals The exchange of calcium in larvae of the mosquito Aedes aegypti

1983 ◽  
Vol 104 (1) ◽  
pp. 139-148 ◽  
Author(s):  
A. I. Barkai ◽  
R. W. Williams
Keyword(s):  
Aedes Aegypti ◽  
Transport System ◽  
External Medium ◽  
Ruthenium Red ◽  
Whole Body ◽  
Transport Systems ◽  
Dilute Solutions ◽  
Calcium Pumps ◽  
Monovalent Ions ◽  
Energy Dependent

The exchange of labelled calcium between the external medium and the whole body was investigated in the larva of Aedes aegypti (L.) using a closed, two-compartmental model. The transport system for the uptake of Ca2+ was found to be saturable and obeyed Michaelis-Menten kinetics. The efficiency of the inward transport of calcium from dilute solutions was markedly reduced by starvation or by ruthenium-red, a selective inhibitor of Ca2+ activated ATPase, indicating that this transport system is energy dependent. Unlike transport systems for the major monovalent ions, the Ca2+ transport system is not located in the anal papillae, since removal of these organs resulted in enhanced Ca2+ fluxes. While over 95% of the calcium in the larva appeared to be distributed in the extracellular haemolymph, only 16% of the total calcium was readily exchangeable with the external medium; thus the majority of the calcium is apparently bound to haemolymph constituents. The results suggest that calcium pumps consisting of Ca2+ activated ATPases play an important role in the absorption of Ca2+ from dilute solutions in the gut and its reabsorption from the urine in the rectum.

scholarly journals The Absorption Of Chloride Ions By The Anal Papillae Of Diptera Larvae

1938 ◽  
Vol 15 (1) ◽  
pp. 152-160 ◽  
Author(s):  
H. J. KOCH
Keyword(s):  
Fresh Water ◽  
Body Surface ◽  
Body Fluid ◽  
Salt Content ◽  
Chloride Content ◽  
Chloride Ions ◽  
The Body ◽  
Whole Body ◽  
Anal Papillae ◽  
Diptera Larvae

By micro-chloride determinations combined with other observations, it is shown that Chironomus and Culex larvae are able to take up chloride parenterally from solutions with a chloride content corresponding to that of ordinary fresh water. This active absorption takes place exclusively in the anal papillae (anal gills). Since, in Chironomus, salt diffuses continually through the whole body surface, these organs, by their salt-absorbing function, play an important part in maintaining the salt content of the body fluid.

Whole Body Surface Assessment – Implementierung und Erfahrungen von 360° 3D Ganzkörperscans: Möglichkeiten zur Objektivierung und Verlaufskontrolle an den Extremitäten und am Körperstamm

2019 ◽  
Vol 51 (04) ◽  
pp. 240-248
Author(s):  
Lucas Etzel ◽  
Konstantin Christoph Koban ◽  
Zhouxiao Li ◽  
Konstantin Frank ◽  
Riccardo Enzo Giunta ◽  
...  
Keyword(s):  
Body Surface ◽  
Whole Body ◽  
Surface Assessment

Zusammenfassung Hintergrund Dreidimensionale (3D) Oberflächenaufnahmen haben sich als objektiver Mehrwert in der Planung und Dokumentation unterschiedlicher plastisch chirurgischer Eingriffe erwiesen. Obwohl Oberflächen- und Volumenanalysen für einzelne Bereiche wie der Brust und des Gesichts im klinischen Alltag eingesetzt werden, war es bislang nicht ausreichend möglich, Auswirkungen auf die gesamte Körperoberfläche zu erfassen und zu quantifizieren. Ziel dieser Studie war die Implementierung von 360° Ganzkörperscans zur zukünftigen Therapie-Evaluierung beim Lipödem. Patienten, Material und Methoden Drei unterschiedliche 3D Oberflächenscanner (Eva, Thor und Sense) wurden am Probanden hinsichtlich ihrer Reproduzierbarkeit und Präzision für 360° Aufnahmen evaluiert. Unter einem standardisierten Setting bestehend aus einem automatischen Drehteller und definierten Posen wurden axiale Umfangsmessungen und schichtweise Volumina bestimmt. Statistische und klinische relevante Abweichungen wurden untersucht. Ergebnisse Ein standardisierter 360° Scan Ablauf wurde implementiert. Die Reproduzierbarkeit aller Scanner war zufriedenstellend (p > 0,05). Es zeigten sich vergleichbare axiale Umfangsmessungen und Volumina für den Eva und Thor Scanner (p > 0,05). Der Sense Scanner erreichte eine ausreichende Messgenauigkeit im Thoraxbereich, jedoch signifikante Abweichungen an der unteren Extremität (p < 0,05). Die Datenauswertung konnte auf ausgewählte klinische Beispiele übertragen werden. Schlussfolgerung Es konnte erfolgreich eine 360° Oberflächenaufnahmetechnik und Analyse in der Plastischen Chirurgie eingeführt werden. Zwei der getesteten Geräte ermöglichen objektive Umfangs- und Volumenmessungen am gesamten Körper. Das dritte Gerät, der günstige Sense Scanner, ermöglichte zwar 360° Aufnahmen, jedoch war dessen Präzision nicht für alle Bereiche ausreichend. In Zukunft könnten somit die Auswirkungen unterschiedlicher Therapien an der gesamten Körperoberfläche evaluiert werden.

Regulation of rectal secretion in saline-water mosquito larvae living in waters of diverse ionic composition

1977 ◽  
Vol 66 (1) ◽  
pp. 83-96 ◽  
Author(s):  
T. J. Bradley ◽  
J. E. Philips
Keyword(s):  
Chemical Composition ◽  
External Medium ◽  
Saline Water ◽  
Ionic Composition ◽  
Malpighian Tubules ◽  
Fluid Composition ◽  
Mosquito Larvae ◽  
Major Site ◽  
Osmotic Concentration ◽  
Anal Papillae

1. Larvae of the saline-water mosquito Aedes campestris were adapted to three waters, all having an osmotic concentration of 700 mOsm, but differing in ionic rations. The (Na+Mg) SO4 medium was much moretoxic than the NAHCO3 or the NaCl media. 2. Ionic and osmotic concentrations of haemolymph and rectal secretion were measured in larvae adapted to all three media. The ratio of ionic concentrations in the rectal secretion reflected those in the external medium to which the larvae had been adapted, with the exception of SO42-, which was possibly replaced by HCO3-in the secretion. These differences in rectal fluid composition persisted even though all ligated recta were bathed in the same artificial haemolymph. 3. The Malpighian tubules were found to be the major site of SO42- excretion. In media containing high levels of NA+, Mg2+, K+, Cl- and HCO3-, the rectum secreted a hyperosmotic fluid containing these ions at concentrations several times greater than those found in the haemolymph. 4. These data provide the basis for speculation on the functioning of anal papillae in waters of diverse chemical composition.

scholarly journals Ground Applications of Vectobac® WDG with A1 Super-Duty Mist Sprayer® and Micronair® AU5000 Atomizer for Suppression of Aedes aegypti Populations in the Florida Keys

2021 ◽  
Vol 37 (4) ◽  
pp. 271-279
Author(s):  
Heidi L. Murray ◽  
Catherine A. Pruszynski ◽  
Lawrence J. Hribar
Keyword(s):  
Aedes Aegypti ◽  
Mosquito Control ◽  
Larval Mortality ◽  
Florida Keys ◽  
Application Rate ◽  
Residential Area ◽  
Distilled Water ◽  
Bacillus Thuringiensis Israelensis ◽  
Key West ◽  
F1 Generation

ABSTRACT Since 2011, the Florida Keys Mosquito Control District (FKMCD) has used the WALS® application strategy with VectoBac® WDG containing Bacillus thuringiensis israelensis via helicopter in Key West for the control of Aedes aegypti larval populations. In 2018, FKMCD conducted a study to determine the effectiveness of using a trailer-mounted A1 Super Duty Mist Sprayer® (A1 Mist Sprayers) with a Micronair® AU5000 (Micron Group) atomizer to apply VectoBac WDG by ground at the rate of 0.5 lb/acre (0.56 kg/ha). Bioassay cups were placed in a residential area encompassing open, moderate, and heavy cover scenarios between 0 and 300 ft (0–91.44 m) perpendicular to the spray line. An application rate of 0.5 lbs/acre (0.56 kg/ha) was used. Bioassay cups were collected after application and returned to the laboratory where 100 ml of distilled water and 10 F1 generation Ae. aegypti larvae were added. Laval mortality was monitored at 2, 4, and 24 h. Three separate runs were completed during the summer of 2018. Average larval mortality at 24 h was &gt;90%. The field trial demonstrated sufficient efficacy to introduce this method of larviciding into operational use.

scholarly journals Whole-body imaging of neural and muscle activity during behavior in Hydra: bidirectional effects of osmolarity on contraction bursts

2019 ◽  
Author(s):  
Wataru Yamamoto ◽  
Rafael Yuste
Keyword(s):  
Nervous System ◽  
Body Size ◽  
Neuronal Activity ◽  
Environmental Conditions ◽  
Muscle Activity ◽  
Muscle Cells ◽  
Major Effect ◽  
Whole Body ◽  
Effect Of Temperature ◽  
Whole Body Imaging

AbstractThe neural code relates the activity of the nervous system to the activity of the muscles to the generation of behavior. To decipher it, it would be ideal to comprehensively measure the activity of the entire nervous system and musculature in a behaving animal. As a step in this direction, we used the cnidarian Hydra vulgaris to explore how physiological and environmental conditions alter the activity of the entire neural and muscle tissue and affect behavior. We used whole-body calcium imaging of neurons and muscle cells and studied the effect of temperature, media osmolarity, nutritional state and body size on body contractions.In mounted Hydra, changes in temperature, nutrition or body size did not have a major effect on neural or muscle activity, or on behavior. But changes in media osmolarity altered body contractions, increasing them in hipo-osmolar media solutions and decreasing them in hyperosmolar media. Similar effects were seen in ectodermal, but not in endodermal muscle. Osmolarity also bidirectionally changed the activity of contraction bursts neurons, but not of rhythmic potential neurons.These findings show osmolarity-dependent changes in neuronal activity, muscle activity, and contractions, consistent with the hypothesis that contraction burst neurons respond to media osmolarity, activating ectodermal muscle to generate contraction bursts. This dedicated circuit could serve as an excretory system to prevent osmotic injury. This work demonstrates the feasibility of studying the entire neuronal and muscle activity of behaving animals.Significance StatementWe imaged whole-body muscle and neuronal activity in Hydra in response to different physiological and environmental conditions. Osmolarity bidirectionally altered Hydra contractile behavior. These changes were accompanied by corresponding changes in the activity of one neuronal circuit and one set of muscles. This work is a step toward comprehensive deciphering of the mechanisms of animal behavior by measuring the activity of all neurons and muscle cells.

scholarly journals Aedes Aegypti: Energetics of Osmoregulation

1982 ◽  
Vol 101 (1) ◽  
pp. 135-141 ◽  
Author(s):  
H.A. EDWARDS
Keyword(s):  
Oxygen Consumption ◽  
Energy Cost ◽  
Sea Water ◽  
External Medium ◽  
Minimum Energy ◽  
Body Volume ◽  
Wet Weight ◽  
Minimum Energy Cost ◽  
Anal Papillae ◽  
Theoretical Minimum

1. Oxygen consumption of A. aegypti larvae, about 210 mul l g−1 tissue wet weight h−1, does not change when the salinity of the environment is changed. The number of mitochondria in the anal papillae, a salt-absorbing epithelium, increases as the external medium is diluted. There is no difference in oxygen consumption between isolated anal papillae in 0, 2 and 20% sea water. The papillae represent about 5% of body volume and their oxygen consumption is about 2% of the animal's total. The theoretical minimum energy cost of osmoregulation is four orders of magnitude smaller than the measured figure for the anal papillae alone. Osmoregulatory phenomena which would explain the recorded observations are discussed.

scholarly journals Echinopla Cherapunjiensis sp. n. (Hymenoptera, Formicidae) from India

2012 ◽  
Vol 46 (4) ◽  
pp. e-52-e-54 ◽  
Author(s):  
H. Bharti ◽  
I. Gul
Keyword(s):  
Body Surface ◽  
Whole Body ◽  
Deep Excavations ◽  
Nicobar Islands

Echinopla Cherapunjiensis sp. n. (Hymenoptera, Formicidae) from India Echinopla cherapunjiensis Bharti et Gul, sp. n. is described from India. This represents the second species of genus reported in India, with only Echinopla lineata senilis Mayr, 1862 described earlier from Nicobar Islands. The species distinctly differs from all other known species of this genus by the following combination of characters: globose shape of head, presence of seven teeth on petiolar scale, flat dorsum of mesosoma with promesonotal and mesometanotal sutures obsolete, whole body surface (dorsum) rough due to sinuous sculpture, deep excavations and spiky elevations on head and mesosoma and excavations on gaster.

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