Mean Urea Concentration Research Articles

Evaluate the propylthiouracil on thyroid, liver and kidney functions in male rabbits

This work was conducted to investigate the effect of Propylthiouracil thyroid kidney and liver functions in male rabbits. Fifteen (15) rabbits were divided into three groups: a control group, which received tap water only, a low-dose group that received 50 mg/kg oral propylthiouracil and a high-dose group, which received 100 mg/kg oral propylthiouracil. Rabbits were dosed daily for three weeks. After the three-weeks period, the rabbits were sacrificed and blood samples were collected for hormonal and biochemical analysis. Showed changes in liver enzymes as a result of liver tissue damage. Propylthiouracil caused an increase in creatinine concentration, alkaline phosphatase levels, and liver enzyme levels. PTU treatment had no significant effect on the mean urea concentration level. In view of the changes summarized, the increase or decrease in this parameter arises from the reduction in the level of thyroid hormones which, in turn, affect most body tissues.

Evaluation of the levels of renal indices and blood pressure in Type 2 diabetes mellitus, hypertensive and normotensive subjects in Port Harcourt, Nigeria

This study was designed to find out the impact of diabetes mellitus on the renal integrity of diabetic patients following exposure to hypertension and diabetes. This was achieved by examining the urea and creatinine concentrations and creatinine clearance of both diabetics and non-diabetics in Port Harcourt. A total of 165 subjects comprising 32 (19.39%) male diabetics, 53 (31.12%) female diabetics, 48 (29.09%) nondiabetic males and 32 (19.39%) non-diabetic females participated in the study. Results showed that 9.09% of male and 21.91% of female diabetics were hypertensive. Mean urea concentrations obtained were 6.35 ±1.55 mmol/L and 5.56 ± 2.24 mmol/L in the diabetic males and females respectively while in the non-diabetic males and females, the results were 5.66 ± 1.23 mmol/L and 5.07 ± 1.71 mmol/L respectively which was not significantly different (p>0.05, F crit. = 1.98). The creatinine concentration in the diabetic males and females were 93.46 ± 24.97 μmol/L and 89.15 ± 28.01 μmol/L respectively while in the non-diabetic male and female subjects it was 84.64 ± 29.06 μmol/L and 81.69 ± 37.27 μmol/L respectively. These means were not significant (p>0.05, F crit. = 1.65). In both male and female diabetics, the creatinine clearance was reduced in the subjects following 8 years and above of exposure to diabetes mellitus, which is an indication of commencement of progressive loss of renal function in the diabetic patients. Thus, measurement of creatinine clearance should be included in the routine assessment of renal function especially in type 2 diabetes mellitus patients.Keywords: Renal failure, diabetes mellitus, hyperglycaemia, hypoglycaemia, renal clearance.

The eff ect of selected factors on urea concentration in the milk of Polish Holstein-Friesian cows

The objective of the study was to determine the relationships between milk urea concentration and factors such as lactation number, stage of lactation, month and season of the test day, age at calving, milk yield and protein percentage. Data for the calculations consisted of 7,731 test-day records from 1,078 Polish Holstein-Friesian cows. Test-day milking was performed for first, second and third lactations during the period from December 2010 to December 2011. Calculations were performed using the MIXED procedure in SAS/STAT. A mixed linear model using was applied in which parameters were estimated by the restricted maximum likelihood (REML) method. Least squares means for fixed eff ects in the model were compared by the Tukey-Kramer test. The first lactation diff ered significantly (p<0.05) from the second and third in terms of mean urea concentration, but there were no significant diff erences between the second and third lactations. For primiparous cows the milk urea concentration increased throughout lactation, but for older cows it increased only up to 7–8 months of lactation. Urea concentrations did not diff er significantly in the same stages of consecutive lactations, i.e. the first and second or second and third. Statistically significant diff erences were noted between the first and third lactations only in months 9 and 10 of lactation. Seasonal changes in milk urea content varied depending on the lactation number. In the first lactation the milk urea concentration was lowest in spring and highest in autumn. This tendency was not observed in the second and third lactation. Milk urea concentration was positively associated with both milk yield and protein percentage

Placental Growth Factor Levels in Preeclampsia Compared to Normal Pregnancy

Objective: To identify and analyze the differences in the levels of
 PlGF in preeclampsia and normal pregnancy.
 
 Method: This was a cross-sectional observational qualitative study
 of PlGF in preeclampsia and normal pregnancy. The number of samples
 in case and control group was 30 in each groups.
 
 Result: We found that mean of maternal age in the preeclampsia
 group was 28.53 years and 25.23 years in the control group. Mean
 parity in preeclampsia and control group was 2.33 and 1.56, respectively.
 Mean hemoglobin level in preeclampsia and control group
 was 11.97 and 11.99, respectively. Mean maternal blood glucose
 level was 87.0 in the preeclampsia group, and 87.9 in the control
 group. In the preeclampsia group mean urea concentration was
 16.45, while it was 22.78 in the control group. Mean creatinine level
 was 0.92 in the preeclampsia group and 0.64 in the control group.
 Mean SGPT and SGOT in the preeclampsia group was 23.36 and
 21.97, while in the control group was 29.86 and 26.20. Test results
 showed that PlGF levels was significantly different between the preeclampsia
 and control group. Mean PlGF in the preeclampsia and control
 group was 42.10 and 452.33 respectively, with p

Plasma Potassium Concentration Changes Associated with Trimethoprim used for Urinary Tract Infections

ABSTRACTBackgroundHyperkalaemia has been reported with high‐dose trimethoprim (20 mg/kg/day) and standard‐dose trimethoprim (6 mg/kg/day) plus sulfamethoxazole use.AimTo investigate changes in plasma potassium concentrations in patients prescribed standard‐dose trimethoprim 300 mg daily for urinary tract infections.MethodA retrospective cohort study of hospital patients with urinary tract infections treated with trimethoprim or other antibacterials (control group) for more than 5 days. Plasma potassium concentration, creatinine and urea were compared at baseline and at the completion of treatment.ResultsThere were 31 patients in the trimethoprim group and 65 patients in the control group. End–of–therapy mean plasma potassium concentrations increased significantly from baseline in the trimethoprim group (4.2 ± 0.4 mmol/L to 4.5 ± 0.5 mmol/L; p = 0.002) but not in the control group. End–of–therapy mean plasma potassium concentrations were also higher in the trimethoprim group (4.5 ± 0.5 mmol/L vs 4.2 ± 0.5 mmol/L; p = 0.007). 65% of the trimethoprim group developed end–of–therapy hyperkalaemia versus 39% of the control group. Mean creatinine concentration in the trimethoprim group increased by an average of 21% from baseline but did not change in the control group. The trimethoprim group showed no change in mean urea concentration but a decrease was noted in the control group.ConclusionTreating urinary tract infections with trimethoprim 300 mg daily for more than 5 days was associated with an increase in plasma potassium concentration.

Carbamylated Hemoglobin as a Therapeutic Marker in Hemodialysis

Carbamylation requires isocyanic acid derived from urea. Carbamylation of hemoglobin (Hb) produces carbamylated Hb (carbHb), which could serve as a marker of posttranslational protein modification possibly associated with such uremic complications as atherosclerosis. Since relative carbHb levels are determined by mean urea concentration and duration of exposure, they could be used to assess the adequacy of a patient’s hemodialysis (HD) regimen. We therefore determined the relationship between carbHb and urea kinetics in patients with chronic renal failure (CRF) undergoing maintenance HD. In pre-HD determinations as well as in nondialyzed subjects including healthy subjects and CRF patients without dialysis, carbHb correlated well with blood urea nitrogen (BUN) concentrations, especially with BUN averaged for the preceding 1–3 months. In HD patients, carbHb correlated significantly with urea kinetics (time-averaged concentration of urea, or TAC_urea, K_t/V and urea reduction rate). The estimated mean urea concentration in HD patients calculated from the relationship between carbHb and averaged BUN over 3 months in the nondialyzed groups was lower than TAC_urea, suggesting that TAC_urea may be an overestimate. Pre-HD BUN is not a good nutritional index since detrimental decreases in urea elimination from the body can elevate pre-HD BUN independently of nutrition. We therefore devised a new nutritional index, BUN/carbHb, which correlated significantly with serum albumin as well as the normalized protein catabolic rate. These results demonstrate that carbHb accurately reflects uremic control and the BUN/carbHb ratio could serve as an index of nutritional state in HD patients.

Major constituents, leptin, and non-protein nitrogen compounds in mares' colostrum and milk.

Five Haflinger mares were hand-milked at 0 h (pre-suckle) and 6 h (postsuckle), 12, 24, 48, 72 and 96 h after parturition. Total solids, protein, fat, lactose, calculated gross energy content, leptin and non-protein nitrogen components (urea, alpha-amino nitrogen, creatinine and allantoin) were determined. The levels of the major constituents differed significantly in pre-suckle colostrum from subsequent samples. Leptin levels were the highest in whole (9 ng x mL(-1) of immunoreactive human equivalent HE +/- 0.48 ng x mL(-1), SEM) and skimmed (7.8 ng HE x mL(-1) +/- 0.52 ng x mL(-1), SEM) pre-suckle colostrum, declined sharply at 6 hours postpartum, and more slowly subsequently. Mean urea concentration was constant at around 5.0 mM, while a-amino N increased over the observation period and creatinine and allantoin decreased. These findings provide a further indication that mares' milk can be regarded as a functional food.

Bulk milk urea concentrations and their relationship with cow fertility in grazing dairy herds in Southern Chile

Milk urea determination is being used as a broad indicator of protein/energy imbalance in dairy herds. The main purpose of this study was to compare blood and bulk milk urea values in grazing herds, to evaluate their seasonal variation under South Chilean conditions, and to examine their potential relationships with herd fertility. The association between herd blood urea concentration (mean of seven lactating cows) and bulk milk urea concentration (tank containing milk from the previous 24 h) was determined in 21 dairy herds. Reference values, seasonal and herd variance, and the frequency of herds with values outside a range of 2.5 to 7.3 mmol/l were determined in bulk milk samples obtained monthly for a period of one year from 82 suppliers at two creameries located in southern Chile. Finally, bulk milk urea was measured every two weeks in samples from 24 herds, and the first service conception rate (FSCR) from 2153 dairy cows was determined. Mean bulk urea concentration was highly correlated with mean herd blood urea concentration ( r=0.95; p<0.01). Mean urea concentration in the bulk milk samples obtained during one year from 82 herds was 4.9±1.2 mmol/l, with a range of 1.5 to 11.6 mmol/l. The highest values were found during spring and the lowest values during the summer. There was a high seasonal variation (CV=13–47%) and between-herd variation (CV=20–31%). Out of a total of 984 samples, 5.4% had urea values >7.3 mmol/l and 3.8% had values <2.5 mmol/l. Of the 82 herds, 27% had values outside the reference interval (2.5–7.3 mmol/l) on two or more occasions. FSCR was lower in herds when the bulk milk urea was >7.3 mmol/l (50.7%) than in cows, where the urea concentration was <5.0 mmol/l (73.8%) at the time of insemination. The study concluded that bulk milk urea concentrations provided information similar to herd blood urea concentrations in local grazing dairy herds. There was a high frequency of herds with abnormal values, with large variations between herds and between seasons. Increased milk urea concentrations during spring were associated with lower conception rates.

A Statistical Evaluation of Animal and Nutritional Factors Influencing Concentrations of Milk Urea Nitrogen

Data from 35 trials with 482 lactating cows fed 106 diets were used to study the effects of animal and dietary factors on the relationship between milk and blood urea N and the value of milk urea N in the assessment of protein status. In two trials, urea N in whole blood and in blood plasma were closely related (r2=0.952); the slope was not significantly different from 1.0, and the intercept was not significantly different from 0. Regression of milk urea N on blood urea N with a mixed effects model using all 2231 observations yielded the equation: milk urea N (milligrams of N per deciliter)=0.620×blood urea N (milligrams of N per deciliter) + 4.75 (r2=0.842); this model accounted for a significant interaction of cow and blood urea N. Single factors that yielded significant regressions on milk urea N with the mixed effects models were dietary crude protein (CP) (percentage of dry matter; r2=0.839), dietary CP per megacalorie of net energy for lactation (NEL) (r2=0.833), excess N intake (r2=0.772), N efficiency (r2=0.626), and ruminal NH3 (r2=0.574). When all factors were analyzed at once, 12 were significant in a mixed effects model. Blood urea N, body weight, yield of fat-corrected milk, dietary CP content, excess N intake, dry matter intake, and days in milk were positively related to milk urea N, and parity, milk and fat yield, dietary CP per unit of NEL content, and NEL intake were negatively related to milk urea N. In one trial, the mean urea concentration was 35 times greater in urine than in milk; lower proportions of total urea excretion in milk were observed in the a.m. sampling (1.8%) than in the p.m. sampling (3.3%). Measuring urea N in a composite milk sample from the whole day substantially improved reliability of data. The number of cows fed a specific diet that must be sampled to determine mean milk urea N within 95% confidence intervals with half widths of 1.0 and 2.0mg of N/dl was estimated to be 16 and 4, respectively.

Serum osmolality in the coelacanth, Latimeria chalumnae: urea retention and ion regulation.

Samples of blood (hemolyzed) were obtained from the renal vein, the hepatic portal vein, and the heart of a freshly thawed specimen of Latimeria chalumnae. The coelacanth uses high concentrations of urea to maintain its serum osmolality at approximately that of sea water. The mean value for the total osmolality was 1181 milliosmoles per liter. The mean values (milliequivalents per liter) were: for sodium, 181; for potassium, 51.3; for calcium, 6.9; for magnesium, 28.7; for chloride, 199; and for bicarbonate, 4.7. The mean urea concentration was 355 millimoles per liter, and the mean nonprotein nitrogen was 1343 milligrams percent. Heart blood showed significantly lower values for osmolality (921 milliosmoles per liter) and nonprotein nitrogen (1030 mg percent) and was probably less severely contaminated with products of protein breakdown. Fluid from the anterior chamber of the eye showed values of 952 milliosmole/liter; the urea value for this fluid was 303 mmole/liter, and the magnesium was 7.3 meq/liter. The magnesium value for the aqueous humor was used to correct the abnormally high concentrations in the hemolyzed serum. The high level of serum potassium also was attributed to hemolysis.