Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.1.27.1 (RNase)
16,360 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The influence of a variety of clinical and biochemical parameters on the activities in serum of ribonuclease (RNAse) selective for polycytidylic acid (RNAse C) were examined in 90 adult patients with cancer. The clinical data base determined on each patient included: RNAse C level, carcinoembryonic antigen (CEA) level, age, sex, race, presence (or absence of metastases, type of cancer, site of metastasis, renal function blood urea nitrogen [BUN], creatinine), hepatic function (bilirubin, alkaline phosphatase), and nutritional status (percent ideal body weight, percent weight loss, and albumin). Common tumor types studied included: colon (21), lung (18), breast (15), and hepatocellular carcinoma (10). For comparison, 175 nonmalignant control patients were studied to establish the normal range for RNAse. In patients with cancer, RNAse levels were increased in 57% and CEA levels were above 10 ng/dl in 36%. Although patients with BUN greater than 25 mg/dl or creatinine greater than 1.5 mg/dl were not entered on the study, nonetheless, RNAse was significantly (P less than 0.05) associated with both BUN and creatinine. Nutritional status also had an important influence on RNAse levels as both percent weight loss and percent ideal body weight were significantly (P less than 0.05) associated with circulatory RNAse: weight loss resulted in higher RNAse levels. These results account in part for the increased RNAse levels seen in those malignant conditions such as pancreatic and lung cancer commonly associated with weight loss in advanced stage. The possibility that circulatory RNAse C determination will provide a sensitive means for assessing nutritional status in cancer patients will require prospective evaluation.
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PMID:Influence of nutritional status on circulatory ribonuclease C levels in patients with cancer. 298 Nov 45

An investigation was carried out into how the low-molecular mass proteins beta 2-microglobulin, lysozyme, and ribonuclease were excreted over 8 h after high fluid intake (22 ml/kg of body weight in 15 min). With increasing urine flow rate the amount of lysozyme excreted per hour or per millimole creatinine increased more markedly than that of beta 2-microglobulin while at the same time the excretion rate of ribonuclease decreased. The effect of urinary flow upon the excretion rates of the various low-molecular mass proteins has to be considered as a preanalytical factor when these proteins are used as indicators of tubular dysfunction.
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PMID:Diuresis-dependent excretions of low-molecular mass proteins in urine: beta 2-microglobulin, lysozyme, and ribonuclease. 306 76

The diagnostical relevance of the low-molecular proteins ribonuclease, beta 2-microglobulin and lysozyme in serum and urine to detect a reduced glomerular filtration rate was examined in 52 patients with chronic renal diseases. The radioisotope clearance using 99mTc-DTPA was the base reference; the reference values of the low-molecular proteins were estimated in a control group. Ribonuclease was increased above the upper borderline value, if the glomerular filtration rate was lower than 1.24 ml s-1. Creatinine, beta 2-microglobulin and lysozyme remain yet in part in the normal range. The estimation of the ribonuclease in serum is suitable to detect an impaired glomerular filtration rate if the creatinine value is still not increased. Thereby, the diagnostics in renal diseases may be improved in the creatinine-blind area.
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PMID:[The low molecular weight proteins ribonuclease, beta 2 microglobulin and lysozyme in the serum and urine of patients with chronic kidney diseases]. 307 Oct 37

The diagnostic value of the low-molecular mass proteins ribonuclease, beta 2-microglobulin, and lysozyme in serum for the detection of reduced glomerular filtration rates was evaluated. The values of these proteins and of serum creatinine investigated in 52 patients suffering from chronic renal diseases were plotted against 99m-Tc-diethylenetriaminopentaacetate clearance as an indicator of glomerular filtration rate. Log-transformed data showed a good fit of linearity. Considering the 95% confidence limits of the regression equations, ribonuclease increased above the normal range when the glomerular filtration rate was lower than 1.24 ml/s whereas the other analytes partly remained within their normal limits. Out of those 18 patients with glomerular filtration rates lower than 1.24 ml/s, all patients showed elevated ribonuclease levels. beta 2-Microglobulin, creatinine, and lysozyme were increased in 17, 14, and 12 cases, respectively. Ribonuclease and beta 2-microglobulin showed similar results when other diagnostic criteria (specificity, efficiency and predictive values) were taken into account. We recommend ribonuclease determination in serum for the detection of reduced glomerular filtration rate in the normal range of creatinine. The test is diagnostically powerful, cheap and easy to perform.
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PMID:Diagnostic value of low-molecular mass proteins in serum for the detection of reduced glomerular filtration rate. 332 Feb 63

In order to investigate the role of renal factors in affecting trypsinogen 1 metabolism and excretion in chronic pancreatic disease, serum immunoreactive trypsin (IRT), urinary IRT, gamma-glutamyltransferase (GGT), alpha-glucosidase (AGL) and RNase outputs and the molecular size distribution of serum and urine IRT were studied in 8 control subjects, 18 cases with pancreatic cancer, and 23 cases with chronic pancreatitis. Serum chromatography demonstrated that most immunoreactivity eluted as trypsinogen 1. Smaller amounts of immunoreactivity at higher molecular weights were also observed. Urine chromatography displayed both trypsinogen 1 and heavier molecular forms. An inverse linear correlation was noticed between creatinine clearance and serum trypsinogen 1 levels. Multiple regression analysis (urinary IRT output dependent and GGT, AGL, and RNase predictor variables) showed a significant linear correlation. RNase was found to be the most important parameter in explaining urinary IRT output. Mild variations in the glomerular function seem to be able to influence serum trypsinogen 1 levels. Urinary IRT excretion is principally explained by a disturbance in the tubular reabsorption of low molecular weight proteins, such as RNase.
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PMID:Renal factors in serum trypsinogen 1 metabolism and excretion in chronic pancreatic disease. 336 41

An optimized assay is described for the catalytic activity determination of serum ribonuclease, using polycytidylic acid as substrate and measuring the released acid-soluble ultra-violet absorbing products. Recommended final reaction concentrations are 0.3 mmol/l polycytidylic acid, 200 mmol/l imidazole/HCl buffer, pH 7.0, and 50 mmol/l NaCl. Optimal concentrations for the precipitation procedure, guaranteeing sufficient precipitation and minimal decomposition of unreacted substrate, are 160 mmol/l perchloric acid and 4 mmol/l lanthanum nitrate. Coefficients of variation for the method (within series and between days) ranged from 2.2 to 7.9%. No sex-related differences of catalytic activity were observed. In 63 blood donors with normal values of serum creatinine, the upper limit of the reference intervals (99th percentile) was 33.7 kU/l.
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PMID:An optimized micromethod for determining the catalytic activity of serum ribonuclease. 370 Dec 75

To determine whether tubular reabsorption of low molecular weight proteins (LMWPs) alters ischemic tubular injury, rats were infused with 25 mg of lysozyme (isoelectric point (pI) 11.3), cytochrome C (pI 10.6), ribonuclease (pI 8.7), or myoglobin (pI 7.0), and during this time 25 minutes of bilateral renal artery occlusion (RAO) was induced. RAO control rats received either saline or 25 mg of albumin. Renal injury was assessed 24 hours later by blood urea nitrogen, creatinine, and histology. Lysozyme, ribonuclease, and myoglobin each exacerbated ischemic damage (increased tubular necrosis, cast formation, azotemia), but to comparable degrees (e.g., blood urea nitrogen range 75 +/- 8 to 100 +/- 5 mg/dl versus controls, 29 +/- 2 to 36 +/- 7; p less than 0.01). Rendering lysozyme anionic (pI 4.5) by succinylation did not diminish its acute renal failure-potentiating effect. Cytochrome C which is freely filtered but poorly reabsorbed had a minimal impact on the ischemic process. Infusion of LMWPs did not alter blood pressure, renal blood flow, or induce renal injury in the absence of RAO. During a sublethal ischemic event (10 minutes of RAO) LMWP infusion exacerbated proximal tubular luminal membrane damage before an adverse effect on other critical determinants of cell integrity were apparent (adenine nucleotide pools, oxidant stress). We conclude that endocytic LMWP reabsorption by proximal tubules can exacerbate superimposed ischemic tubular necrosis independent of any direct nephrotoxic protein effect. This action is not influenced by protein isoelectric point and appears to be mediated by a primary intensification of ischemic luminal membrane damage.
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PMID:Low molecular weight proteinuria exacerbates experimental ischemic renal injury. 380 17

Four groups of cadmium-exposed persons, from different workplaces and with different types of exposure, have been followed for periods of 9-20 years. In one group the total observation time is over 30 years, since they were included in Friberg's original study. The studies include determination of inulin or creatinine clearance, protein excretion and specific indicators of renal tubular dysfunction. The results indicate that once tubular dysfunction is established, it is irreversible, even when it is minor. In some persons it was noted that the development of renal dysfunction seemed to be a multistage process. The initial stage is characterized by an increased excretion of low molecular weight proteins like beta 2-microglobulin and ribonuclease. After a period of several years with no or low exposure, there was a relatively sharp increase in excretion of total proteins and albumin and a decrease in glomerular filtration rate. This is interpreted as being the result of further increases in renal concentration of cadmium and in spread of cadmium along the tubules. Metallothionein absorption in the tubules, its catabolism and synthesis must play an important role for the development and progress of the tubular dysfunction. It was not possible to show that a decrease in glomerular filtration rate occurs before low molecular weight proteinuria.
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PMID:Long-term observations on tubular and glomerular function in cadmium-exposed persons. 637 91

The activities of serum acid ribonuclease (RNase) were determined in patients with malignant neoplasm or with renal failure. The levels were markedly increased in myelogenous leukemia and renal failure, and only slightly increased in solid cancers, lymphoid malignancies and multiple myeloma. These increases correlated significantly with serum LDH activity in myelogenous leukemia and with creatinine levels in other malignancies or renal failure. The acid RNase content of granulocytes was 22.7-fold higher than that of lymphocytes. The increase of serum acid RNase may suggest an increased granulocyte destruction in myelogenous leukemia and a reduced glomerular filtration in other malignant neoplasms and renal failure.
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PMID:Activities of serum acid ribonuclease in patients with malignant neoplasms or with renal failure. 658 Sep 78

The cardioinactive digoxin metabolite, dihydrodigoxin, has been conjugated to bovine serum albumin and to bovine pancreatic ribonuclease by the periodate oxidation method. Rabbits immunized with the dihydrodigoxin-bovine serum albumin conjugate formed antibodies which bound a radioiodinated dihydrodigoxin-ribonuclease conjugate. This binding was inhibited by dihydrodigoxin. After affinity chromatography on a digoxin-ribonuclease-Sephacryl immunoadsorbent to remove antibodies which cross-reacted with digoxin, dihydrodigoxin was 300 times more effective than digoxin in inhibiting the binding of tracer by antibody. Digoxin-absorbed antidihydrodigoxin antibodies were coupled to Sephacryl and were used to develop a solid-phase radioimmunoassay capable of detecting 250 to 500 pg of dihydrodigoxin in 1 ml of human serum or urine. This radioimmunoassay has been used to define the pharmacokinetics of the metabolite in four normal human volunteers who ingested 125 to 500 micrograms of dihydrodigoxin by mouth. Dihydrodigoxin was quickly absorbed, with maximal serum concentrations achieved within 45 to 105 min, followed by a rapid fall in serum immunoreactivity over 2 to 4 hr and then by a slower, more gradual decline. The terminal half-life (beta) in serum varied from 4.24 to 11.9 hr (mean +/- S.E. = 8.1 +/- 1.3 hr). Most of the administered dose was excreted in the urine, with cumulative urinary recovery varying inversely with the dose. Urinary half-lives averaged 13.8 +/- 2.1 hr, and renal clearance rates were similar to those of creatinine. Dihydrodigoxin is rapidly absorbed and excreted in man and appears to be eliminated from the body at a faster rate than digoxin.
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PMID:The development and application of a radioimmunoassay for dihydrodigoxin, a digoxin metabolite. 706 78


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