Postnatal Adjustment in Renal Function

PEDIATRICS ◽  
1981 ◽  
Vol 68 (6) ◽  
pp. 802-813 ◽  
Author(s):  
Jose Strauss ◽  
Salha S. Daniel ◽  
L. Stanley James

Renal function was studied serially in 17 healthy term infants during the hours immediately following birth. Of 14 infants delivered vaginally eight received placental blood transfusion and six did not. The remaining three infants were delivered by cesarean section and received placental blood transfusion. Results indicate that the general pattern of change in urine output (V), clearance of inulin (CIN), and p-aminohippuric acid (CPAH), was similar in all infants despite a wide range in each of the functions measured. The pattern showed an initial increase in V, CIN, and CPAH followed by a decline to low values in all infants by 3 hours of age. Urine osmolality and output generally changed in opposite directions. During the first hour the values for V ranged from 0.02 to 0.47 ml/min; for CIN, from 0.5 to 9.1 ml/min; for CPAH, from 1.4 to 21.8 ml/min; and for osmolality, from 98 to 457 mOsm/kg. By 4 hours of age the values for V ranged from 0.01 to 0.15 ml/min; for CIN, from 0.8 to 3.7 ml/min; for CPAH, from 0.8 to 7.5 ml/min; and for osmolality, from 240 to 520 mOsm/kg. The initial values of V, CIN, and CPAH, as well as the changes, were greatest in those infants who received a placental transfusion; however, there were no statistical differences among the means of the various groups. By 4 hours of age, the range of values observed in the initial measurement was much less pronounced. This probably reflects the achievement of stability of renal circulation following adaptation to a variety of stresses during the intrapartum period.

1975 ◽  
Vol 10 (1) ◽  
pp. 73-83
Author(s):  
J.E.S. Graham ◽  
T.C. Hutchinson

Abstract Crude oil spills are increasingly likely to occur from drilling, pumping and transportation activities as oil development proceeds at a rapid pace. These spills may occur over the wide range of climatic conditions which obtain in Canada. Little is known of oil toxicity at different temperatures; consequently, laboratory studies were made of the variability of the toxicity of aqueous extracts of a Norman Wells crude oil to freshwater algae over the temperature range 5°C to 35°C. Two unicellular green algae were studied: Chlamydomonas eugametos and Chlorella vulgaris. Their response (measured by cell numbers) varied with temperature and species. Whereas Chlamydomonas eugametos showed a general pattern of growth inhibition by oil at all temperatures with maximum inhibition at 25°C, Chlorella vulgaris showed general growth stimulation by oil with maximum stimulation at 25°C, this temperature was chosen for all further experimentation. All experiments were done using unialgal cultures and sterile technique. Cells were grown in 50 ml of nutrient medium (BBM) in 125 ml Erlenmeyer flasks. Such flasks allow gas exchange and permit loss of volatile hydrocarbons. Aqueous extracts were made by slowly stirring 5% crude oil with the nutrient medium for six hours using a magnetic mixer. The extract was then allowed to sit for two to four hours before the lower fraction was drawn off for use. Experiments were carried out in controlled environment chambers (±2°C) with a twelve hour light-dark cycle. All further experiments used a similar methodology. (Note: Chlamydomonas eugametos experiments were carried out on a rotary shaker at 125 rpm.) An attempt was made to determine the reason for the remarkable stimulation in growth of Chlorella vulgaris #29 at 25°C. This organism has been described in the literature as heterotrophic. Thus three reasons for stimulation seemed possible: 1. heterotrophic uptake of hydrocarbons directly from solution; 2. heterotrophic uptake of organic compounds formed or released by microbial breakdown of hydrocarbons (the aqueous extract of crude was not sterile); or 3. the use of CO2 released to solution by microbial respiration. The original experiment was repeated in the dark at 20°C to determine if stimulation still occurred. It did not, since cells exposed to the aqueous extract decreased in numbers. However, after two weeks the cells were illuminated and even though experimental flasks started off with depleted populations, they outgrew the control cells within two weeks. This suggested that if stimulation was related to heterotrophism, it must, at least in this case, have been the unusual case of photoheterotrophism. The reasons for this stimulation of growth are currently under investigation. Several methods are being employed to investigate the suspected heterotrophism. Experiments will be done to determine whether light energy is essential to the stimulation. Two varieties of Chlorella vulgaris, i.e. #29 and #260 are heterotrophic and autotrophic respectively, are to be used in experiments. Sterile aqueous extracts made by pressure ultrafiltration will be used. These experiments should determine whether algal growth stimulation is related to heterotrophism or whether microbial degradation of hydrocarbons is the real source of stimulation. Although the toxicity of crude oil may be rapidly ameliorated by physical and/or biological phenomena, one must still be aware of the possibility of a large input of organic carbon causing extensive eutrophication. Thus both toxicity and eutrophication will cause a selection, in terms of survival, in a natural environment. It is evident that although an oil spill may not totally destroy an ecosystem, it will certainly alter its natural composition considerably.


2020 ◽  
Vol 104 (9-10) ◽  
pp. 775-780 ◽  
Author(s):  
Julia Mühlbauer ◽  
Johannes de Gilde ◽  
Michael Mueller-Steinhardt ◽  
Stefan Porubsky ◽  
Margarete Walach ◽  
...  

2011 ◽  
Vol 64 (9-10) ◽  
pp. 503-506 ◽  
Author(s):  
Suzana Raicevic-Sibinovic ◽  
Aleksandar Nagorni ◽  
Vesna Brzacki ◽  
Mirjana Radisavljevic

Introduction. Renal dysfunction is one of complications in patients with obstructive icterus. It is important to recognize it early and take adequate measure to prevent its occurrence. One third of the patients with obstructive icterus have deterioration of renal function before surgical intervention. The aim of the research was to assess the renal dysfunction markers in patients with obstructive icterus. The following factors were examined: diuresis, urinary sodium concentration, sodium excretory fraction, urine osmolality, osmotic concentration index, creatinine concentration index and renal index of lesion. Material and methods. The study included 85 patients with obstructive icterus (50 patients before surgical intervention and 35 after surgical intervention) and 30 patients without icterus as a control group. The patients with normal renal function before the development of the disease were included. Results. Malignant etiology was present in 39 patients and benign in 46 patients of the examined group. The evaluation parameters of renal function were examined in all of the patients. Creatinine concentration index led to the greatest change in the coefficient value of an internal consistency, showing that it was the best renal function marker in the examined group of patients with icterus. The next one was the urinary osmolality, since its exclusion would lead to a decrease in the value of Cronbach ? coefficient to 0.06. Icterus and surgical intervention show statistically significant effects to change in the value of the markers of laboratory differentiation of renal function, observed as an entire set. Discussion and conclusion. The examination showed that the concentration clearances of creatinine and urine osmolality are the parameters which point to the probability of renal dysfunction occurrence in obstructive icterus.


Neonatology ◽  
2002 ◽  
Vol 81 (4) ◽  
pp. 236-243 ◽  
Author(s):  
Thomas Brune ◽  
Henk Garritsen ◽  
Ralf Witteler ◽  
Anette Schlake ◽  
Jörg Wüllenweber ◽  
...  

2012 ◽  
Vol 58 (5) ◽  
pp. 680-697 ◽  
Author(s):  
Cristiane Cäsar ◽  
Klaus Zuberbühler

Abstract There is relatively good evidence that non-human primates can communicate about objects and events in their environment in ways that allow recipients to draw inferences about the nature of the event experienced by the signaller. In some species, there is also evidence that the basic semantic units are not individual calls, but call sequences and the combinations generated by them. These two findings are relevant to theories pertaining to the origins of human language because of the resemblances of these phenomena with linguistic reference and syntactic organisation. Until recently, however, most research efforts on the primate origins of human language have involved Old World species with comparatively few systematic studies on New World monkeys, which has prevented insights into the deeper phylogenetic roots and evolutionary origins of language-relevant capacities. To address this, we review the older primate literature and very recent evidence for functionally referential communication and call combinations in New World primates. Within the existing literature there is ample evidence in both Callitrichids and Ce-bids for acoustically distinct call variants given to external disturbances that are accompanied by distinct behavioural responses. A general pattern is that one call type is typically produced in response to a wide range of general disturbances, often on the ground but also including inter-group encounters, while another call type is produced in response to a much narrower range of aerial threats. This pattern is already described for Old World monkeys and Prosimians, suggesting an early evolutionary origin. Second, recent work with black-fronted titi monkeys has produced evidence for different alarm call sequences consisting of acoustically distinct call types. These sequences appear to encode several aspects of the predation event simultaneously, notably predator type and location. Since meaningful call sequences have already been described in Old World primates, we suggest that basic combinatorial vocal communication has evolved in the primate lineage long before the advent of language. Moreover, it is possible that some of these communicative abilities have evolved even earlier, or independently, as there is comparable evidence in other taxonomic groups. We discuss these findings in an attempt to shed further light on the primate stock from which human language has arisen.


1959 ◽  
Vol 197 (5) ◽  
pp. 1093-1096
Author(s):  
Joseph H. Perlmutt

The effect of increased pressure in one kidney, produced by ligation of its vein, on contralateral renal function was investigated in eight anesthetized dogs. Kidney function was determined under the same experimental conditions in five dogs, but without renal vein ligation. For the latter group, renal function, on the average, remained reasonably stable. After left renal vein ligation, findings for the right kidney were as follows: a) decreased urine flow, amounting maximally to 9.5–41.4% of control flows; b) slight increase of questionable significance in creatinine clearance; c) inconstant changes in PAH clearance; d) increase in urine osmolality to hypertonic values; e) decrease in solute-free water clearance; f) slight rise of questionable significance in total solute clearance; and g) either no change or inconstant changes in excretion rates Na+ and K+. The data indicate that the oliguria resulted solely from increased renal tubular reabsorption of water, suggesting liberation of antidiuretic hormone as the possible mechanism. Direct nervous influences on tubular reabsorption of water cannot, however, be presently ruled out.


2001 ◽  
Vol 61 (2) ◽  
pp. 191-196 ◽  
Author(s):  
S. D. HILÁRIO ◽  
V. L. IMPERATRIZ-FONSECA ◽  
A. de M. P. KLEINERT

Flight activity of Plebeia pugnax Moure (in litt.) was studied in six colonies coming from Cunha, SP, from July to October 1994. Twice a week, from 8:00 a.m. to 6:00 p.m., for 5 minutes every half-hour, all the bees entering and leaving the hives were counted. Six hundred counts were made and the materials that foragers carried were recorded. Data were analysed in relation to temperature, relative humidity, light intensity and day time. Foragers' flight activity was relatively constant in a wide range of temperature, from 22°C to 34°C. The minimum temperature for the beginning of flight activity was 14°C. Effective flight activity (when foragers of all colonies were leaving the hives) occurred at 15°C. These bees also flew within a wide range of relative humidity, from 30% to 100%, decreasing slowly after 50%. Flight activity increased as light intensity rose and it has also increased as the hours passed by, reaching a peak around midday and decreasing gradually afterwards. Pollen was collected all day long, while resin collection was relatively constant and debris transportation was slightly higher after 10:00 h. From all known Plebeia species, this one flew on the lowest temperature ever registered for this genus.


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