Bio: H. Husdan is an academic researcher from Toronto Western Hospital. The author has contributed to research in topics: Urine & Excretion. The author has an hindex of 11, co-authored 22 publications receiving 857 citations.
TL;DR: Total chromogen, true, and AutoAnalyzer methods of measuring serum and urine creatinine by the Jaffe reaction were investigated and their precision, recovery, and sample stability determined.
Abstract: Total chromogen, true, and AutoAnalyzer methods of measuring serum and urine creatinine by the Jaffe reaction were investigated. Some factors influencing this reaction were examined. These included wavelength, blank, linearity, and conditions of color development. Modifications of the three methods were made and their precision, recovery, and sample stability determined. The interference of ketones and glucose were measured. Finally, the values obtained by the three methods on the same samples of serum and urine were compared statistically.
TL;DR: Thirteen obese females were studied during 14 periods of fasting, lasting 2 to 4 weeks, in which they consumed only noncaloric fluids, and changes in weight, in fluid-electrolyte and acid-base balance and in kidney function are concerned.
Abstract: Thirteen obese females were studied during 14 periods of fasting, lasting 2 to 4 weeks, in which they consumed only noncaloric fluids. This paper concerns itself primarily with changes in weight, in fluid-electrolyte and acid-base balance and in kidney function. The 11 patients who underwent 3 weeks of fasting lost an average of 12.7 pounds in the first week, 6.8 pounds in the second and 5.6 pounds in the third. The decreasing rate of weight loss with time could be related to decreases in urine output, basal metabolism and in activity of the patients. Urine sodium decreased gradually to about 20 mEq./day after 1 week of starvation. During early refeeding, urine sodium almost disappeared regardless of sodium intake and weight gain paralleled sodium retention. Urine chloride paralleled urine sodium whereas urine potassium fell more slowly although progressively. In 1 subject the aldosterone secretion rate which doubled after 1 week of fasting rose to its highest level during refeeding. Mild metabolic acidosis predominated in the first 2 weeks of fasting, a tendency to respiratory alkalosis in the third and metabolic alkalosis during refeeding. The clearances of urea and endogenous creatinine decreased during fasting. Data on urine pH, titratable acidity, ammonia, phosphorus and nitrogen are shown.
TL;DR: The largest group were those 47 patients with chronic glomerulonephritis; the underlying renal disease was polycystic kidney disease and the remaining 47 had a variety of other kidney disease including five in whom the cause was not obvious.
Abstract: experience 1759 patient months). The ages of these patients ranged from 3 to 74 years with a mean of 49.9 . Five patients were under the age of 16 years. The largest group were those 47 patients with chronic glomerulonephritis. Another 25 patients had a systemic disease: 15 had diabetes mellitus and three had primary amyloidosis. In 13 patients the underlying renal disease was polycystic kidney disease. The remaining 47 had a variety of other kidney disease including five in whom the cause was not obvious.
TL;DR: Findings are consistent with the hypotheses that (1) alcohol withdrawal results in a “rebound” increase in antidiuretic hormone activity, following prolonged suppression of ADH by continuous drinking, and (2) increased aldosterone activity occurs during continuous drinking but is masked by the opposing effects of ethanol.
Abstract: A metabolic balance study of 5–7 days' duration was carried out on 8 chronic alcoholic males during alcohol withdrawal; 5 nonalcoholic patients were used as controls. Four alcoholic subjects without liver damage showed significant weight gain and Na + retention. Of 4 alcoholics with liver damage, only one showed a comparable Na + retention, and none gained weight. The 5 controls were close to Na + balance, and 4 of them lost weight. There was no significant difference between groups with respect to K + balance. Blood and plasma volume were significantly higher in the alcohol withdrawal group than in the controls, and the urine specific gravity tended to rise appreciably during the first 2 days of alcohol withdrawal. The alcohol withdrawal group, but not the controls, showed evidence of systemic alkalosis, as indicated by elevation of arterial blood pH and urine pH, decreased urinary NH 4 and titratable acidity, and reduced serum K + . These findings are consistent with the hypotheses that (1) alcohol withdrawal results in a “rebound” increase in antidiuretic hormone activity, following prolonged suppression of ADH by continuous drinking, (2) increased aldosterone activity occurs during continuous drinking but is masked by the opposing effects of ethanol; it is suggested that when alcohol is withdrawn the aldosterone effect becomes evident.
TL;DR: Factors related to serum ionic fluoride values are (a) tea as an important source of dietary F-, (b) the lack of significant variation during daytime hours, and (c) the Lack of significant difference in concentration between serum and plsma F-.
Abstract: We used the Orion fluoride electrode system to determine the normal range of serum ionic fluoride concentrations and to investigate its relationship to sex and age (A). 87 normal men, aged 18-92 years (mean, 46 years), and 49 normal women, age 19-64 years (mean, 38 years), participated in the study. At the 95% confidence limits, males less than 45 years old had a normal range of 0.29 to 1.52 mumol/litre and males greater than or equal to 45 years old 0.29 + 0.0101 (A-45) to 1.52 + 0.0101 (A-45) mumol/litre. Females, however, had a normal range of 0.022A - 0.32 to 0.022A + 1.07 mumol/litre. A group of 51 men 18-44 years old was compared with a group of 36 men 46-92 years old. The mean serum F- of the older group was shown to be significantly greater (P less than 0.01) than that of the younger group. Factors related to serum ionic fluoride values are (a) tea as an important source of dietary F-, (b) the lack of significant variation during daytime hours, and (c) the lack of significant difference in concentration between serum and plsma F-.
TL;DR: Elevated levels of microalbuminuria strongly predict the development of clinical diabetic nephropathy, and these levels of AER are potentially reversible, and their detection and treatment may prevent diabetic renal disease.
Abstract: The overnight urinary albumin excretion rate (AER) of 87 patients with insulin-dependent diabetes mellitus was measured in 1966-67, 14 years later information was obtained on 63 of the original cohort; those alive were restudied, and for those who had died relevant clinical information and case of death were recorded. The development of clinical diabetic nephropathy ('Albustix'positive proteinuria) was related to the 1966-67 AER values. Clinical proteinuria developed in only 2 of 55 patients with AER below 30 microgram/min but in 7 of 8 with AER between 30 and 140 microgram/min. The risk of clinical diabetic nephropathy in the latter group was twenty-four time higher than inthe former. 9.1% of patients with AER below 30 microgram/min had died, compared with 37.5% with higher AER. The two groups did not differ significantly in age, sex composition, and initial blood pressure. Mean duration of diabetes was longer, but not significantly so, in those with AER above 30 microgram/min. Thus, elevated levels of microalbuminuria strongly predict the development of clinical diabetic nephropathy. These levels of AER are potentially reversible, and their detection and treatment may prevent diabetic renal disease.
TL;DR: There is an essential relation between poverty and fluorosis as malnutrition is found to play an aggressive role in its severity, as the lack of access to clean water denies the most essential of all rights, the right to life.
Abstract: ‘Water is life,’ so central to human life, yet over one billion people across the world have no access to safe drinking water. Of late, there has been increasing global attention focused on resolving water quality problems especially in developing countries, as the lack of access to clean water denies the most essential of all rights, the right to life. The latest estimates suggest that around 200 million people, from among 25 nations the world over, are under the dreadful fate of fluorosis. India and China, the two most populous countries of the world, are the worst affected. India is plagued with numerous water quality problems due to prolific contaminants mainly of geogenic origin and fluoride stands first among them. The weathering of primary rocks and leaching of fluoride-containing minerals in soils yield fluoride rich groundwater in India which is generally associated with low calcium content and high bicarbonate ions. The unfettered ground water tapping exacerbates the failure of drinking water so...
TL;DR: The effect of insulin on CH2O suggests that insulin's effect on sodium excretion is due to enhancement of sodium reabsorption in the diluting segment of the distal nephron, and a reduction in UNaV associated with insulin administration is demonstrated.
Abstract: The effects of insulin on the renal handling of sodium, potassium, calcium, and phosphate were studied in man while maintaining the blood glucose concentration at the fasting level by negative feedback servocontrol of a variable glucose infusion. In studies on six water-loaded normal subjects in a steady state of water diuresis, insulin was administered i.v. to raise the plasma insulin concentration to between 98 and 193 muU/ml and infused at a constant rate of 2 mU/kg body weight per min over a total period of 120 min. The blood glucose concentration was not significantly altered, and there was no change in the filtered load of glucose; glomerular filtration rate (CIN) and renal plasma flow (CPAH) were unchanged. Urinary sodium excretion (UNaV) decreased from 401 plus or minus 46 (SEM) to 213 plus or minus 18 mueq/min during insulin administration, the change becoming significant (P smaller than 0.02) within the 30-60 min collection period. Free water clearance (CH2O) increased from 10.6 plus or minus 0.6 to 13 plus or minus 0.5 ml/min (P smaller than 0.025); osmolar clearance decreased and urine flow was unchanged. There was no change in plasma aldosterone concentration, which was low throughout the studies, and a slight reduction was observed in plasma glucagon concentration. Urinary potassium (UKV) and phosphate (UPV) excretion were also both decreased during insulin administration; UKV decreased from 66 plus or minus 9 to 21 plus or minus 1 mueq/min (P smaller than 0.005), and tupv decreased from 504 plus or minus 93 to 230 plus or minus 43 mug/min (P smaller than 0.01). The change in UKV was associated with a significant reduction in plasma potassium concentration. There was also a statistically significant but small reduction in plasma phosphate concentration which was not considered sufficient alone to account for the large reduction in UPV. Urinary calcium excretion (UCaV) increased from 126 plus or minus 24 to 200 plus or minus 17 mug/min (P smaller than 0.01). These studies demonstrate a reduction in UNaV associated with insulin administration that occurs in the absence of changes in the filtered load of glucose, glomerular filtration rate, renal blood flow, and plasma aldosterone concentration. The effect of insulin on CH2O suggests that insulin's effect on sodium excretion is due to enhancement of sodium reabsorption in the diluting segment of the distal nephron.
TL;DR: It is concluded that the determination of the protein/creatinine ratio in single urine samples obtained during normal daylight activity, when properly interpreted by taking into consideration the effect of different rates of creatinine excretion, can replace the 24-hour urine collection in the clinical quantitation of proteinuria.
Abstract: Quantitation of urinary protein excretion is used extensively for diagnostic and prognostic purposes and to assess the effects of therapy. The method most commonly used to measure urinary protein relies on 24-hour urine collections, which are time consuming, cumbersome, and often inaccurate. We reasoned that the urinary protein/creatinine ratio in a single voided urine sample should correlate well with the quantity of protein in timed urine collections. In a study of 46 specimens we found an excellent correlation between the protein content of a 24-hour urine collection and the protein/creatinine ratio in a single urine sample. The best correlation was found when samples were collected after the first voided morning specimen and before bedtime. We conclude that the determination of the protein/creatinine ratio in single urine samples obtained during normal daylight activity, when properly interpreted by taking into consideration the effect of different rates of creatinine excretion, can replace the 24-hour urine collection in the clinical quantitation of proteinuria. In the presence of stable renal function, a protein/creatinine ratio of more than 3.5 (mg/mg) can be taken to represent "nephrotic-range" proteinuria, and a ratio of less than 0.2 is within normal limits.
TL;DR: Fluoride has greatest potential as a therapy for osteoporosis once bone has been lost, and the trials have included patients with different severity of disease, suggesting that there is point in the bone loss spectrum at which even a potent bone-stimulating agent such as fluoride is ineffective.
Abstract: Osteoporosis defined as low bone mass and increased susceptibility to fracture is a reflection of the sum of peak bone mass and any bone that has been lost once peak mass has been attained. Several strategies have been applied to optimize peak bone mass and to prevent bone loss. Fluoride has greatest potential as a therapy for osteoporosis once bone has been lost. It has been demonstrated both experimentally and clinically to stimulate bone formation directly and to increase bone mass in patients who already have osteoporosis. Several bone formation/stimulation therapies are under development, and some of these have reached the stage of clinical trial. None of these therapies has been as extensively studied as fluoride, and none is sufficiently advanced in development to be clinically available in the next 3 to 5 years. Fluoride therapy for osteoporosis is already performed in many countries, and approval for use in osteoporosis in the United States is pending. The first clinical trials of NaF therapy for osteoporosis were reported by Rich and Ensinck in 1961. Since then, hundreds of reports on the successes and failures of fluoride therapy have appeared in the literature. At first glance, it seems disappointing and inexplicable that, after 40 years of research, fluoride is still considered an experimental drug in the United States. One plausible explanation is that much of the early research on this drug was suboptimal, including the author's contributions. Fluoride as a naturally occurring element is difficult to patent, and this has kept major pharmaceutical companies from investing heavily in fluoride therapy despite its obvious potential. As a result, pharmacologic and pharmacokinetics studies of fluoride are limited in scope, as are phase I and phase II human toxicology and dose-finding studies. Most early studies of large doses of plain NaF were unable to demonstrate a consistent effect on fracture rate despite a consistent and dramatic effect on bone density. Once this became obvious and as new technologies for measuring bone density became available, it became equally clear that future clinical trials would have to be performed using different formulations of fluoride and lower doses. This approach has not resulted in uniformly positive clinical trials, and one must look elsewhere for answers. The most compelling explanation is that the trials have included patients with different severity of disease, suggesting that there is point in the bone loss spectrum at which even a potent bone-stimulating agent such as fluoride is ineffective. This possibility should provoke a reappraisal of the earlier negative studies: was the failure a result of the drug or of patient selection? The answer to this question is crucial, because these failures have cast a long shadow over the safety of fluoride and are contributing more to the absence of this drug from the pharmacopoeia than any other factor.