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.

Sodium Regulation and Adaptation to Fresh Water in Gammarid Crustaceans

1968 ◽  
Vol 48 (2) ◽  
pp. 359-380
Author(s):  
D. W. SUTCLIFFE
Keyword(s):  
Body Weight ◽  
Fresh Water ◽  
Body Surface ◽  
Sea Water ◽  
Sodium Concentration ◽  
The Body ◽  
Outward Diffusion ◽  
Gammarus Zaddachi ◽  
Freshwater Habitats ◽  
Sodium Regulation

1. Sodium uptake and loss rates are given for three gammarids acclimatized to media ranging from fresh water to undiluted sea water. 2. In Gammarus zaddachi and G. tigrinus the sodium transporting system at the body surface is half-saturated at an external concentration of about 1 mM/l. and fully saturated at about 10 mM/l. sodium. In Marinogammarus finmarchicus the respective concentrations are six to ten times higher. 3. M. finmarchicus is more permeable to water and salts than G. zaddachi and G. tigrinus. Estimated urine flow rates were equivalent to 6.5% body weight/hr./ osmole gradient at 10°C. in M. finmarchicus and 2.8% body weight/hr./osmole gradient in G. zaddachi. The permeability of the body surface to outward diffusion of sodium was four times higher in M. finmarchicus, but sodium losses across the body surface represent at least 50% of the total losses in both M. finmarchicus and G. zaddachi. 4. Calculations suggest that G. zaddachi produces urine slightly hypotonic to the blood when acclimatized to the range 20% down to 2% sea water. In fresh water the urine sodium concentration is reduced to a very low level. 5. The process of adaptation to fresh water in gammarid crustaceans is illustrated with reference to a series of species from marine, brackish and freshwater habitats.

Sodium Balance in Eriocheir Sinensis (M. EDW.). The Adaptation of the Crustacea to Fresh Water

1961 ◽  
Vol 38 (1) ◽  
pp. 153-162
Author(s):  
J. SHAW
Keyword(s):  
Fresh Water ◽  
Body Surface ◽  
Eriocheir Sinensis ◽  
Vital Role ◽  
The Body ◽  
Sodium Balance ◽  
Progressive Reduction ◽  
Uptake Mechanism ◽  
Active Uptake ◽  
Main Factors

1. In Eriocheir sinensis active uptake of sodium plays a vital role in the maintenance of sodium balance. At external concentrations down to about 6 mM./l. the active uptake mechanism is fully saturated and the uptake rate just balances the rate of loss, which occurs primarily through the body surface. At lower external concentrations balance may be achieved, at least in part, by the activation of the uptake mechanism. 2. A hypothesis is put forward to account for the mechanism of adaptation of the Crustacea to fresh water. Two main factors are involved: (a) a progressive reduction in the permeability of the body surface to salts and, (b) the acquisition of an active uptake mechanism with a high affinity for the ions which it transports. 3. This hypothesis is discussed in relation to previous theories on the adaptation of the Crustacea to fresh water.

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.

Osmoregulation in the Larva of the Marine Caddis Fly, Philanisus Plebeius (Walk.) (Trichoptera)

1972 ◽  
Vol 57 (3) ◽  
pp. 821-838
Author(s):  
JOHN P. LEADER
Keyword(s):  
Sodium Chloride ◽  
Osmotic Pressure ◽  
Body Surface ◽  
Sea Water ◽  
Electrical Potential ◽  
Chloride Ion ◽  
Chloride Ions ◽  
The Body ◽  
Electrical Potential Difference ◽  
Caddis Fly

1. The larva of Philanisus plebeius is capable of surviving for at least 10 days in external salt concentrations from 90 mM/l sodium chloride (about 15 % sea water) to 900 mM/l sodium chloride (about 150 % sea water). 2. Over this range the osmotic pressure and the sodium and chloride ion concentrations of the haemolymph are strongly regulated. The osmotic pressure of the midgut fluid and rectal fluid is also strongly regulated. 3. The body surface of the larva is highly permeable to water and sodium ions. 4. In sea water the larva is exposed to a large osmotic flow of water outwards across the body surface. This loss is replaced by drinking the medium. 5. The rectal fluid of larvae in sea water, although hyperosmotic to the haemolymph, is hypo-osmotic to the medium, making it necessary to postulate an extra-renal site of salt excretion. 6. Measurements of electrical potential difference across the body wall of the larva suggest that in sea water this tissue actively transports sodium and chloride ions out of the body.

scholarly journals Multiple giant congenital nevi – a case report / Multipli gigantski kongenitalni nevusi – prikaz slučaja

2011 ◽  
Vol 3 (2) ◽  
pp. 69-76
Author(s):  
Vesna Mikulić
Keyword(s):  
Body Surface ◽  
Psychosocial Problems ◽  
The Body ◽  
Skin Tumor ◽  
Whole Body ◽  
Neurocutaneous Melanosis ◽  
Melanocytic Nevi ◽  
Increased Risk ◽  
Giant Congenital Melanocytic Nevi ◽  
Congenital Melanocytic Nevi

Abstract Giant congenital melanocytic nevi are benign nevomelanocytic proliferations of 20 cm or more in diameter, present at birth. They are primarily found on the posterior trunk, but they may arise on any other part of the body, covering more than 2% of the body surface. Giant congenital nevi are major risk factors for the development of melanoma, and the risk has been estimated to be as high as 5-7%. Persons with giant congenital melanocytic nevi on the head, neck and along the midline of the back are at increased risk for leptomeningeal melanocytic lesions. Most patients with neurocutaneous melanosis present with neurologic manifestations of the disease in the first 2 years of life. Melanoma occurs in 62-80% of cases, but even without neoplasms, symptomatic neurocutaneous melanosis has a poor prognosis. This is a report of a 23-year-old female patient who presented with multiple congenital pigmented and pilous nevi covering over 2% of her total body surface, without malignant alterations or association with other abnormalities. At birth, a nevus covered her neck, shoulders and the upper left arm, whereas several nevi over 5cm in diameter were present in the gluteal region, on the abdomen and legs. During the first 2 years of life, the existing nevi increased in size and progressed into darker brown. New, smaller pigmented changes appeared on the whole body and the face, while at the age of 17 they reached their current size and layout. At puberty, nevi over 10cm in size grew dark hairs. There were neither melanoma nor skin tumor cases in the family. Nuclear magnetic resonance imaging was not performed in the childhood or later in life, but other parameters - neurologic and ophthalmologic findings were in normal range all the time, as was growth and development. A complete photo-documentation was made, including macroscopic and dermoscopic images and regular follow-ups continue. Giant congenital melanocytic nevi may cause considerable esthetic and psychosocial problems. Due to their high malignant potential, association with other abnormalities, no consensus on the treatment, and monitoring problems, giant congenital melanocytic nevi represent a therapeutic problem as well.

Sodium Regulation in the Fresh-Water Amphipod, Gammarus Pulex (L.)

1967 ◽  
Vol 46 (3) ◽  
pp. 499-518
Author(s):  
D. W. SUTCLIFFE
Keyword(s):  
Fresh Water ◽  
Body Surface ◽  
Loss Rate ◽  
Sodium Concentration ◽  
The Body ◽  
Uptake Mechanism ◽  
Sodium Influx ◽  
Sodium Uptake ◽  
Sodium Loss ◽  
Total Sodium

1. Sodium influx and loss rates in Gammarus pulex were measured at constant temperatures. The sodium loss rate was immediately influenced by a change in temperature, with a Q10 of 1.5 to 2.0 at temperatures between 0.3 and 21.5° C. The sodium influx rate is apparently influenced in the same way. 2. The sodium uptake mechanism in G. pulex from three localities was half-saturated at an external concentration of 0.10-0.15 mM/l. sodium. 3. The total sodium loss rate remained approximately constant in animals acclimatized to the range of external concentrations from 2 to about 0.2 mM/l. sodium. 18% of the sodium was lost in urine with a sodium concentration estimated at 30-50 mM/l. The remainder of the sodium loss was due to diffusion across the body surface. 4. In animals acclimatized to concentrations below about 0.2 mM/l. sodium the sodium loss rate was reduced, due to (a) a lower diffusion rate following a fall in the blood sodium concentration, and (b) the elaboration of a more dilute urine. 5. There was a very close association between changes in the blood sodium concentration, the elaboration of a very dilute urine, and the rate of sodium uptake at the body surface. The results indicate that a fall in the blood sodium concentration leads to simultaneous activation of the sodium uptake mechanisms at the body surface and in the antennary glands. 6. It is estimated that, by producing a dilute urine, total sodium uptake in G. pulex is shared equally between the renal uptake mechanism and the mechanism situated at the body surface. 7. In sea-water media G. pulex drinks and expels fluid from the gut. In a medium slightly hyperosmotic to the normal blood concentration the amount imbibed was equal to the normal rate of urine flow when in fresh water.

Ventilatory effectiveness of high-frequency oscillation applied to the body surface

1987 ◽  
Vol 62 (6) ◽  
pp. 2410-2415 ◽  
Author(s):  
T. Fuyuki ◽  
S. Suzuki ◽  
M. Sakurai ◽  
H. Sasaki ◽  
J. P. Butler ◽  
...  
Keyword(s):  
Partial Pressure ◽  
Body Surface ◽  
High Frequency ◽  
Blood Gases ◽  
The Body ◽  
Whole Body ◽  
High Frequency Oscillation ◽  
Frequency Oscillation ◽  
Rib Cage ◽  
Significant Difference

To determine the ventilatory effectiveness of high-frequency oscillation (HFO) at different sites on the body surface, we applied HFO separately to the abdomen, the rib cage, or the whole body in eight anesthetized and paralyzed dogs. Test frequencies were 5, 7, 9, and 11 Hz with tidal volume kept constant at 2.5 ml/kg. During HFO application to the abdomen, we observed significantly higher arterial O2 partial pressure (P less than 0.05) at 5, 7, and 9 Hz and lower arterial CO2 partial pressure (P less than 0.05) at 7, 9, and 11 Hz than with rib cage or whole-body HFO. There was no significant difference in blood gases between rib cage and whole-body HFO. Thus, using blood gases as an index of ventilatory effectiveness, the present study showed that HFO applied at the abdomen was the most effective of the three kinds of body surface HFO. In comparison to rib cage or whole-body application, abdominal HFO was accompanied by substantial paradoxical movement of the diaphragm and rib cage. The associated lung distortion may result in pendelluft, which in turn may be the mechanism for increased ventilatory effectiveness with abdominal application of HFO.

Sign in / Sign up

Export Citation Format

Share Document