Renal handling of pepsinogens A and C in man

1988 ◽  
Vol 75 (6) ◽  
pp. 649-654 ◽  
Author(s):  
Reinier W. ten Kate ◽  
Gerard Pals ◽  
Jan C. Pronk ◽  
Ruud A. Bank ◽  
Aldur W. Eriksson ◽  
...  

1. Fractional excretions of pepsinogens A and C in the urine were investigated in 21 healthy subjects and in 38 patients with chronic renal insufficiency. In eight of the healthy subjects fractional excretions were measured again after oral administration of omeprazole for 9 days. 2. The mean fractional excretion of pepsinogen A was 27.6% (range 4.4–73.9%) in healthy subjects and remained unchanged after omeprazole administration. In patients with renal failure the mean fractional excretion of pepsinogen A was 37.9% (range 7.0–81.9%). The mean fractional excretion of pepsinogen C was 1.0% (range 0.04–6.8%) in healthy subjects and decreased after omeprazole. In patients with chronic renal diseases a sharp rise in fractional excretion of pepsinogen C was observed once glomerular filtration rate was less than 40 ml/min. 3. Fractional excretion of pepsinogen A was unexpectedly high for a negatively charged protein with a molecule mass of 40 000 daltons. This might be explained by the presence of the positively charged activation peptide. Furthermore, pepsinogen C seemed to be almost entirely reabsorbed from the glomerular filtrate and a tubular reabsorption maximum appeared to be present. Pepsinogen C may, therefore, be a new marker of tubular function. The cause of the remarkable difference in tubular handling of two quite similar low-molecular-mass proteins remains to be elucidated.

1969 ◽  
Vol 47 (7) ◽  
pp. 619-626 ◽  
Author(s):  
A. Gonda ◽  
N. Wong ◽  
J. F. Seely ◽  
J. H. Dirks

The effects of unilateral vasodilatation and alterations in the mean arterial pressure upon the renal handling of calcium and magnesium were studied by clearance methods in dogs. Unilateral vasodilatation was produced by infusion of acetylcholine or bradykinin into the left renal artery, while arterial pressure was altered by aortic constriction, carotid occlusion and vagotomy, or by systemic infusion of angiotensin. Urinary electrolyte excretion was increased markedly by the infusion of each vasodilator and also varied directly with the mean arterial pressure, despite the absence of any significant changes in the filtered load. The fractional excretion of both calcium and magnesium correlated significantly with that of sodium. These results indicate that acute changes in renal hemodynamics modify the tubular reabsorption of divalent cations as well as alter sodium reabsorption.


1972 ◽  
Vol 71 (1) ◽  
pp. 24-36 ◽  
Author(s):  
Ariel Gordin ◽  
Pirkko Saarinen

ABSTRACT An account is given of a methodological study of the double-antibody radioimmunoassay of human TSH, using highly purified labelled human TSH as tracer. It was shown that conventional paper electrophoresis was not adequate for studying the purity of labelled human TSH. When polyvinylchloride (Pevikon®) electrophoresis was used, four subfractions could still be separated, even though, on paper electrophoresis, the material seemed to be homogeneous. Only two of the four Pevikon fractions were immunoreactive. Purification of labelled human TSH by Pevikon electrophoresis also improved the sensitivity of the assay. Specific activities of about 100 mCi/mg gave the highest initial binding capacity, produced least damage to the labelled hormone and showed the best stability of the tracer without influencing the sensitivity of the method. In different storage conditions, labelled human TSH was found to be most stable at −20°C and diluted 1/100. Only in pregnancy did the addition of HCG seem necessary. The mean TSH value in healthy subjects was 3.6 ± 1.4 μU/ml (mean±sd) with a range from 1.6 μU/ml to 8.8 μU/ml.


2019 ◽  
Vol 30 (5) ◽  
pp. 585-592 ◽  
Author(s):  
Nicola Montemurro ◽  
Paolo Perrini ◽  
Vittoriano Mangini ◽  
Massimo Galli ◽  
Andrea Papini

OBJECTIVEOdontoid process fractures are very common in both young and geriatric patients. The axial trabecular architecture of the dens appears to be crucial for physiological and biomechanical function of the C1–2 joint. The aim of this study is to demonstrate the presence of a Y-shaped trabecular structure of the dens on axial CT and to describe its anatomical and biomechanical implications.METHODSFifty-four C2 odontoid processes in healthy subjects were prospectively examined for the presence of a Y-shaped trabecular structure at the odontocentral synchondrosis level with a dental cone beam CT scan. Length, width, and axial area of the odontoid process were measured in all subjects. In addition, measurements of the one-third right anterior area of the Y-shaped structure were taken.RESULTSThe Y-shaped trabecular structure was found in 79.6% of cases. Length and width of the odontoid process were 13.5 ± 0.6 mm and 11.2 ± 0.9 mm, respectively. The mean area of the odontoid process at the odontocentral synchondrosis was 93.5 ± 4.3 mm2, whereas the mean one-third right anterior area of the odontoid process at the same level was 29.3 ± 2.5 mm2. The mean area of the odontoid process and its length and width were similar in men and women (p > 0.05). No significant difference was found in the mean area of the odontoid process in people older than 65 years (94 ± 4.2 mm2) compared to people younger than 65 years (93.3 ± 4.4 mm2; p > 0.05).CONCLUSIONSThe authors identified a new anatomical entity, named the Y-shaped trabecular structure of the odontoid process, on axial CT scans. This structure appears to be the result of bone transformation induced by the elevated dynamic loading at the C1–2 level. The presence of the Y-shaped structure provides new insights into biomechanical responses of C2 under physiological loading and traumatic conditions.


2018 ◽  
Vol 15 (1) ◽  
pp. 74-78
Author(s):  
Mohammadali Nazarinia ◽  
Asghar Zare ◽  
Mohammad javad Fallahi ◽  
Mesbah Shams

Background:Systemic sclerosis is a disorder of connective tissue with unknown cause, affecting the skin and internal organs, characterized by fibrotic changes.Objective:To determine the correlation between serum homocysteine level and interstitial lung involvement in systemic sclerosis. </P><P> Materials and Methods: In this case – control study, 59 patients who fulfilled the ACR/EULAR classification criteria for systemic sclerosis and were referred to Hafez Hospital of Shiraz, Iran, were included as the case group. Fifty nine healthy subjects were involved as the control group. Patients were divided into two groups based on interstitial lung involvement and two subtypes, diffuse and limited type. Serum homocysteine, vitamin B12, and folate levels compared between the controls, and cases groups.Results:Of 59 case and control group, 53 (%89.8) were female and the mean age did not differ in both groups (P=0.929). Thirty five (%59.3) patients had interstitial lung involvement and 38(%64.4) had diffuse cutaneous systemic sclerosis. The mean serum homocysteine level was 13.9±6.3 µmol/L in the case and 13.7±9.2 µmol/L in the control group (P=0.86). The mean serum homocysteine level did not differ between the patients with and without interstitial lung involvement (P=0.52). The patients with lung involvement was older than those without lung involvement (P=0.004). Lung disease was more common in diffuse type (P=0.014).Conclusion:In our study, serum homocysteine level did not differ between the patients and healthy subjects. Also, there was no correlation between serum homocysteine level and lung involvement, but lung involvement was more common in older patients and also diffuse subtype.


2021 ◽  
Vol 13 ◽  
pp. 251584142110304
Author(s):  
Emre Aydemir ◽  
Alper Halil Bayat ◽  
Burak Ören ◽  
Halil Ibrahim Atesoglu ◽  
Yasin Şakir Göker ◽  
...  

Purpose: The purpose of this study was to compare the retinal vascular caliber of COVID-19 patients with that of healthy subjects. Methods: This was a prospective case–control study. Forty-six patients who had COVID-19 were successfully treated, and 38 age- and gender-matched healthy subjects were enrolled in this study. Fundus photography was taken using fundus fluorescein angiography (FA; Visucam 500; Carl Zeiss Meditec, Jena, Germany). Retinal vascular caliber was analyzed with IVAN, a semi-automated retinal vascular analyzer (Nicole J. Ferrier, College of Engineering, Fundus Photography Reading Center, University of Wisconsin, Madison, WI, USA). Central retinal artery equivalent (CRAE), central retinal vein equivalent (CRVE), and artery–vein ratio (AVR) were compared between groups. Results: The mean age was 37.8 ± 9.5 years in the COVID-19 group ( n = 46) and 40 ± 8 years in the control group ( n = 38) ( p = 0.45). The mean CRAE was 181.56 ± 6.40 in the COVID-19 group and 171.29 ± 15.06 in the control group ( p = 0.006). The mean CRVE was 226.34 ± 23.83 in the COVID-19 group and 210.94 ± 22.22 in the control group ( p = 0.044). AVR was 0.81 ± 0.09 in the COVID-19 group and 0.82 ± 0.13 in the control group ( p = 0.712). Conclusion: Patients who had COVID-19 have vasodilation in the retinal vascular structure after recovery. As they may be at risk of retinal vascular disease, COVID-19 patients must be followed after recovery.


Gut ◽  
1993 ◽  
Vol 34 (10) ◽  
pp. 1315-1318 ◽  
Author(s):  
I Biemond ◽  
J Kreuning ◽  
J B Jansen ◽  
C B Lamers

1961 ◽  
Vol 38 (4) ◽  
pp. 695-705
Author(s):  
J. B. BALINSKY ◽  
E. BALDWIN

1. Eighty-two single determinations of ammonia and urea excretion by Xenopus laevis indicated that the percentage of ammonia varied from 40 to 80%, with a mean value of 62%. 2. Measurements of excretion on successive days after feeding showed that a large amount of ammonia was produced soon after feeding, but that ammonia excretion declined rapidly. Urea excretion, not so high initially, remained more or less constant until the third or fourth day, often exceeding ammonia excretion at that time. Thereafter, it also declined and the excretion of both substances reached a constant starvation level by the fifteenth day. 3. Both ammonia and urea excretion were equally affected by temperature. The Q10's were near 2 in the range 20-30° C., but greater in the range 10-20° C. 4. At least 86% of ammonia, and 81% of urea were excreted through the cloaca. 5. The mean 24 hr. urine output of Xenopus at 20% C. was 23.6 ml. per 100 g. body weight. 6. Although the blood ammonia concentration did not appear to be zero, the urine/blood concentration ratio of ammonia was greater than 100. The urine/blood concentration ratio of urea was not significantly different from unity, and constant over a very wide range of concentrations. 7. The above result is interpreted to indicate passive glomerular filtration of urea, and little or no tubular reabsorption of water. 8. It is suggested that ammonia is formed in the kidney, and actively secreted into the glomerular filtrate.


2011 ◽  
Vol 69 (3) ◽  
pp. 509-512 ◽  
Author(s):  
Martha Funabashi ◽  
Natya N.L. Silva ◽  
Luciana M. Watanabe ◽  
Taiza E.G Santos-Pontelli ◽  
José Fernando Colafêmina ◽  
...  

Subjective visual vertical (SVV) evaluates the individual's capacity to determine the vertical orientation. Using a neck brace (NB) allow volunteers' heads fixation to reduce cephalic tilt during the exam, preventing compensatory ocular torsion and erroneous influence on SVV result. OBJECTIVE: To analyze the influence of somatosensory inputs caused by a NB on the SVV. METHOD: Thirty healthy volunteers performed static and dynamic SVV: six measures with and six without the NB. RESULTS: The mean values for static SVV were -0.075º±1.15º without NB and -0.372º±1.21º with NB. For dynamic SVV in clockwise direction were 1.73º±2.31º without NB and 1.53º±1.80º with NB. For dynamic SVV in counterclockwise direction was -1.50º±2.44º without NB and -1.11º±2.46º with NB. Differences between measurements with and without the NB were not statistically significant. CONCLUSION: Although the neck has many sensory receptors, the use of a NB does not provide sufficient afferent input to change healthy subjects' perception of visual verticality.


2001 ◽  
Vol 90 (2) ◽  
pp. 665-669 ◽  
Author(s):  
Jorge Brieva ◽  
Adam Wanner

The purpose of the present study was to determine the responsiveness of airway vascular smooth muscle (AVSM) as assessed by airway mucosal blood flow (Q˙aw) to inhaled methoxamine (α1-agonist; 0.6–2.3 mg) and albuterol (β2-agonist; 0.2–1.2 mg) in healthy [ n = 11; forced expiratory volume in 1 s, 92 ± 4 (SE) % of predicted] and asthmatic ( n = 11, mean forced expiratory volume in 1 s, 81 ± 5%) adults. Mean baseline values for Q˙aw were 43.8 ± 0.7 and 54.3 ± 0.8 μl · min−1· ml−1of anatomic dead space in healthy and asthmatic subjects, respectively ( P < 0.05). After methoxamine inhalation, the maximal mean change in Q˙aw was −13.5 ± 1.0 μl · min−1· ml−1in asthmatic and −7.1 ± 2.1 μl · min−1· ml−1in healthy subjects ( P < 0.05). After albuterol, the mean maximal change in Q˙aw was 3.0 ± 0.8 μl · min−1· ml−1in asthmatic and 14.0 ± 1.1 μl · min−1· ml−1in healthy subjects ( P < 0.05). These results demonstrate that the contractile response of AVSM to α1-adrenoceptor activation is enhanced and the dilator response of AVSM to β2-adrenoceptor activation is blunted in asthmatic subjects.


1997 ◽  
Vol 41 (10) ◽  
pp. 2196-2200 ◽  
Author(s):  
L J Lee ◽  
B Hafkin ◽  
I D Lee ◽  
J Hoh ◽  
R Dix

The effects of food and sucralfate on the pharmacokinetics of levofloxacin following the administration of a single 500-mg oral dose were investigated in a randomized, three-way crossover study with young healthy subjects (12 males and 12 females). Levofloxacin was administered under three conditions: fasting, fed (immediately after a standardized high-fat breakfast), and fasting with sucralfate given 2 h following the administration of levofloxacin. The concentrations of levofloxacin in plasma and urine were determined by high-pressure liquid chromatography. By noncompartmental methods, the maximum concentration of drug in serum (Cmax), the time to Cmax (Tmax), the area under the concentration-time curve (AUC), half-life (t1/2), clearance (CL/F), renal clearance (CLR), and cumulative amount of levofloxacin in urine (Ae) were estimated. The individual profiles of the drug concentration in plasma showed little difference among the three treatments. The only consistent effect of the coadministration of levofloxacin with a high-fat meal for most subjects was that levofloxacin absorption was delayed and Cmax was slightly reduced (Tmax, 1.0 and 2.0 h for fasting and fed conditions, respectively [P = 0.002]; Cmax, 5.9 +/- 1.3 and 5.1 +/- 0.9 microg/ml [90% confidence interval = 0.79 to 0.94] for fasting and fed conditions, respectively). Sucralfate, which was administered 2 h after the administration of levofloxacin, appeared to have no effect on levofloxacin's disposition compared with that under the fasting condition. Mean values of Cmax and AUC from time zero to infinity were 6.7 +/- 3.2 microg/ml and 47.9 +/- 8.4 microg x h/ml, respectively, following the administration of sucralfate compared to values of 5.9 +/- 1.3 microg/ml and 50.5 +/- 8.1 microg x h/ml, respectively, under fasting conditions. The mean t1/2, CL/F, CLR, and Ae values were similar among all three treatment groups. In conclusion, the absorption of levofloxacin was slightly delayed by food, although the overall bioavailability of levofloxacin following a high-fat meal was not altered. Finally, sucralfate did not alter the disposition of levofloxacin when sucralfate was given 2 h after the administration of the antibacterial agent, thus preventing a potential drug-drug interaction.


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