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Biomedical subjects

G Ronquist

Publications and source records attributed to G Ronquist.

At least 181 records · Page 10Linked to original sources
PubMed1985

Demonstration of galactosyltransferase activity in human seminal plasma and its relation to sperm penetration in cervical mucus.

The galactosyltransferase activity was determined in seminal plasma from 24 men with various sperm characteristics subdivided in three different groups and from 9 men subjected to vasectomy for the purpose of voluntary sterilization contributing a 4th group. The galactosyltransferase displayed an obligatory dependency on manganese ions for activity. Endogenous glycoproteins of human seminal plasma were poor acceptors for the galactosyltransferase reaction, and a more than 40-fold increase in activity was achieved in the presence of ovomucoid as exogenous acceptor. There were no significant intergroup differences with regard to galactosyltransferase activity. Hence, qualitative and quantitative discrepancies of spermatozoa were not influential on galactosyltransferase activity in a decisive way. An overall positive correlation was registered between galactosyltransferase activity and sperm penetration in cervical mucus (r = 0.53; p less than 0.01).

Cervix Mucus↗
PubMed1985

Sperm motility and interactions among seminal uridine, xanthine, urate, and ATPase in fertile and infertile men.

Semen was collected under standardized conditions from men who were divided into three groups: a control group from normal spermiograms, men with abnormal spermiograms, and azoospermic men following vasectomy. Ultracentrifuged seminal plasma was analyzed for uridine, xanthine, urate, and the pelleted material for Mg2+- and Ca2+-dependent ATPase and protein. No significant intergroup differences were noted except the significant elevation of xanthine of vasectomized men. Uridine that occurs in high concentration in seminal plasma displayed a positive correlation to percentage motile sperms from the 26 men with normal and abnormal spermiograms. It was concluded that an optimal secretory function of uridine may parallel the increasing percentage of sperm with a better quality of motility. A linear relationship between ATPase activity and sperm penetration ability existed only when taken into consideration those 13 specimens with lowest enzyme activity.

Ca(2+) Mg(2+)-ATPase↗
PubMed1985

Biochemical and morphologic studies of the prostate gland in men subjected to radical cystectomy.

Whole human prostate glands obtained from patients undergoing radical cystectomy were dissected into three paired lobes and the various parts of the gland were subjected to biochemical and morphologic examination. No distinct differences were found between the prostate lobes in regard to content of divalent cations, acid phosphatase and ATPase. These findings were concordant with observations at light microscopy. Hence, despite discernible change in cellular appearance, no distinct border was observed between lobes indicating separate "compartments".

Aged↗
PubMed1985

Metabolic and functional effects of phosphoenolpyruvate and adenosine triphosphate on rat hearts subjected to global ischemia.

The effect of phosphoenolpyruvate (PEP) and adenosine triphosphate (ATP) administered during ischemia was investigated, using the paracorporeal rat heart model. During 15 min of global ischemia the hearts were perfused twice with PEP and ATP (supplemented) or with NaCl only (non-supplemented). In hearts that were freeze-clamped after the ischemic period (group A), the myocardial content of high-energy phosphates showed only minor differences between hearts with and without supplemention. In the supplemented hearts there was increased myocardial content of pyruvate and, to some extent, of lactate, indicating that PEP was metabolized to pyruvate and partly to lactate. In groups B and C the hearts were reperfused for 40 min before freeze-clamping. The non-supplemented hearts showed higher energy content and better left ventricular performance and, concomitantly, the creatine kinase isoenzyme MB (CK-MB) efflux was less than for the supplemented hearts. A clear inverse relationship between left ventricular performance and CK-MB efflux indicated that CK-MB served as a marker of cell integrity. These results contrasted with previus finding of an unequivocally positive effect from PEP and ATP administration. Possible explanations are discussed.

Adenosine Triphosphate↗
PubMed1985

Myocardial pyruvate, lactate, and orthophosphate contents under different postischemic conditions. A study in a paracorporeal rat heart model.

The myocardial contents of pyruvate, lactate and orthophosphate after ischemia were investigated in a paracorporeal rat heart model under different conditions. The arterial blood was supplemented with phosphoenolpyruvate (PEP) and adenosine triphosphate early during reperfusion of excised hearts subjected to 15 min of complete global ischemia at 37 degrees C. The increase in myocardial pyruvate was significant after 4 min of reperfusion compared with the content in non-supplemented hearts subjected to the same ischemic trauma. Such dynamic changes were not observed for lactate and orthophosphate under corresponding conditions. The distinct increase in myocardial pyruvate content on supplementation with PEP and adenosine triphosphate was most probably due to an adenosine triphosphate-mediated PEP translocation into myocardial cells, with rapid metabolization of translocated PEP into adenosine triphosphate (in the presence of cellular adenosine diphosphate) and pyruvate. The pyruvate and lactate relationship varied, depending on the postischemic conditions. The postischemic myocardial orthophosphate content was stable, with only minor fluctuations. This possibility to supply the postischemic myocardium with substrate for immediate intracellular energy production is of clinical interest and merits further studies.

Adenosine Triphosphate↗
PubMed1984

Prostatic origin of fucosyl transferase in human seminal plasma--a study on healthy controls and on men with infertility or with prostatic cancer.

Fucosyl transferase was recovered in soluble form in human seminal plasma. The enzyme had very little activity, as it was structurally bound to prostasomes, which are membrane-surrounded organelles in seminal plasma. The fucosyl transferase activity was recorded on Sephadex G200 chromatography of seminal plasma (supernatant after ultracentrifugation) in one single peak coinciding with that of prostate-specific acid phosphatase. Studies on healthy men and on men with prostatic cancer suggest a prostatic origin of fucosyl transferase activity; two of the men with prostatic cancer displayed 50-95% decreased activities. Antiandrogenic therapy in another man with cancer resulted in substantial reductions in seminal plasma contents of fucosyl transferase, ATPase, acid phosphatase and fructose suggesting a role of testosterone in their secretions.

Acid Phosphatase↗
PubMed1984

Naloxone as an adjuvant in chemotherapy of an experimental tumor.

The antitumor effect of DAB (L-2,4 diaminobuturic acid) has been demonstrated in a previous study. Severe side-effects (especially weight loss and severe neurological symptoms) accompanying DAB treatment have raised the theory that DAB, through a direct effect on the hypothalamus, might cause a diabetes insipidus-like condition, which in turn would activate endogenous opiate systems. This study has verified this state of dehydration and hemoconcentration in a group of 41 mice treated daily with 0.5 ml 0,1 M DAB solution IP. A rise in the serum albumin concentration to 28.8 g/l (SD 2.04) was demonstrated, as against 23.7 g/l (SD 2.3) in a control series. Furthermore, to prevent the neurological side-effects, an adjuvant treatment with an opiate antagonist (Nalone; naloxone) was tried in a group of 19 tumor-bearing mice receiving DAB. This group was compared with a group of 19 tumor-bearing mice receiving DAB only. The mortality rate was significantly reduced in the group receiving Nalone together with DAB (2 dead out of 19) compared with the other group (9 dead out of 19). The tumor weight reduction was about the same in the two groups, 40.5% and 46%, respectively. Combined treatment with DAB and Nalone seems to indicate a possible way of reducing the severe side-effects hitherto accompanying DAB alone, making this unique amino acid a potentially useful antitumor agent.

Aminobutyrates↗
PubMed1984

Myocardial high-energy phosphates and function under different postischemic conditions. A study in a paracorporeal rat heart model.

Infusion of phosphoenolpyruvate together with adenosine triphosphate early during reperfusion after ischemia increased the energy content and the left ventricular isovolumic performance in a paracorporeal rat heart model. Excised hearts were subjected to 15 min of complete global ischemia at 37 degrees C before reperfusion. During reperfusion they were either nonworking (empty-beating) or working (performing left ventricular isovolumic work) between 20 and 40 min of reperfusion before freeze-clamping. Early during reperfusion the excised hearts were either supplemented with 144 mumol phosphoenolpyruvate and 0.67 mumol adenosine triphosphate or nonsupplemented (plain saline) administered in a pulsatile arterial blood flow. The supplemented nonworking group showed significantly higher creatine phosphate and adenosine triphosphate contents compared to the nonsupplemented group. However, under postischemic working conditions there were no significant differences in high-energy phosphates between the supplemented and the nonsupplemented groups in spite of significantly better left ventricular isovolumic performance in the supplemented group. Concomitantly the efflux of creatine kinase isoenzyme MB indicating cellular damage was significantly less for this group. The data presented here favor the view of a possible compartmentalized adenosine triphosphate pool with a high metabolic turnover close to the plasma membrane.

Adenosine Diphosphate↗
PubMed1984

Uridine, xanthine, and urate contents in human seminal plasma.

Levels of uridine, xanthine, and urate in the seminal plasma of 73 men with various infertility problems as well as 11 previously fertile men after vasectomy were estimated. Very high concentration (in the mmolar range) compared with other body fluids were recorded for uridine and xanthine, while urate was in about equimolar concentration to that in the serum. Both uridine and xanthine mean values were significantly increased in vasectomized men compared with normal men; otherwise, there was a wide overlapping of the mean values of these two compounds between the two groups. The mean value of urate was maintained at a rather constant level in the two groups. Analysis of "split" fractions favors an origin from prostatic fluid for xanthine and urate and from the seminal vesicles for uridine. Uridine was positively correlated to both fructose and xanthine in oligozoospermic men, to only xanthine in normal men, and negatively to urate in vasectomized men. Urate and xanthine correlated positively in normal and oligozoospermic men. Positive correlations were also observed for xanthine and fructose in oligozoospermic men and for urate and sperm concentration in normal men.

Humans↗
PubMed1984

Comparison of glycosylated hemoglobin with the oral glucose tolerance test. A study in subjects with normoglycemia, glucose intolerance and non-insulin-dependent diabetes mellitus.

At a health survey of 819 subjects, 47-54 years old, the rate of glucose intolerance (GI) was 6.2% (51 subjects) according to 75 g oral glucose tolerance tests (OGTT) and WHO criteria. In GI-subjects, the mean HbA1 was 7.3% (10th-90th percentile range 6.2-8.3%), and significantly higher than the mean HbA1 in 150 subjects with normal OGTT, which was 6.5% (10th-90th percentile range 5.7-7.4%). With an upper normal limit of 7.8% (mean + 2 SD) only 20% of all GI-subjects had a raised HbA1. The differences between 31 GI-subjects, with low HbA1 (mean 6.9%), and 20 GI-subjects, with relatively high HbA1 (mean 7.9%), were not significant with respect to fasting and 2-hour blood glucose, area under glucose curve, body mass index, index of physical activity, rate of hypertension or rate of first degree relatives with diabetes. In an unselected group of 157 subjects, sampled consecutively during the first part of the survey, the mean HbA1 was 6.6% (10th-90th percentile range 5.8-7.5 %) 150 subjects were those with normal OGTT, 6 subjects had GI and only one subject had previously unknown diabetes. No distinct correlations between HbA1 and OGTT fasting or 2 hour values were found in this sample. No correlation was found within the separate groups of 51 GI-subjects and 150 normal subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Glucose↗
PubMed1984

Adverse effects on the brain in cardiac operations as assessed by biochemical, psychometric, and radiologic methods.

In order to describe subclinical brain injury in conjunction with cardiac operations 94 patients were prospectively studied with three brain injury assessment methods: CSF analyses 24 hours after bypass, psychometry, and computed tomography of the brain. Adenylate kinase (AK), a marker of ischemic brain cell injury, was measured in cerebrospinal fluid (CSF) and in serum. In 13% of the patients, a considerable increase in CSF-AK was seen, in 46% there was a moderate increase, and in 41% no or trivial increase. Psychometry measured as change between preoperative scores in a test battery (SS3) revealed a moderate decrease in intellectual function after operation. There was a significant inverse correlation between CSF-AK and SS3 (r = -0.46, p less than 0.001, r2 = 0.21, n = 71). Computed tomography (CT) of the brain was performed preoperatively and postoperatively in 54 patients. Two of these had cerebral infarctions visible on the CT, despite an essentially normal postoperative state. There was no correlation between indices of brain injury and patient diagnosis and length of perfusion. It is concluded that subclinical brain injury is often seen after cardiac operations. Most often the injury appears trivial and/or reversible, but in a minority of cases there is evidence that the brain injury is irreversible. Factor analysis favors the view that the microembolism theory might no longer be a valid concept in modern cardiopulmonary bypass (CPB). Instead, circumstances in the operative field seem more likely to be important causative factors. This interpretation calls for new principles in the search for an improved cerebral protection during cardiac operations.

Adenylate Kinase↗
PubMed1983

Serum sialyltransferase and fucosyltransferase activities in patients with bronchial carcinoma.

Serum sialyltransferases and fucosyltransferases measured by an affinity adsorbent technique were studied in 27 exactly defined patients with malignant pulmonary diseases. Fourteen patients with benign pulmonary diseases and 56 with benign surgical diseases were used as controls. Enzyme activities were expressed as amounts of labeled precursor molecules incorporated into endogenous acceptors in counts per minute (cpm). The mean sialyltransferase activity was 583 cpm in bronchial carcinoma, 485 cpm in benign pulmonary disease and 428 cpm in benign surgical disease. The only statistically significant difference was between bronchial carcinoma and benign surgical disease. The mean fucosyltransferase activity was 813 cpm in bronchial carcinoma, 436 cpm in benign pulmonary disease and 255 cpm in benign surgical disease. All the differences were statistically significant. There were no statistically significant differences between the WHO histologic bronchial carcinoma groups. The correlation between sialyltransferase and fucosyltransferase activity in bronchial carcinoma was statistically significant (r = 0.59). In squamous cell carcinoma (N = 6), it was strongly significant (r = 0.96) and there was a significant correlation also in small cell carcinoma (N = 10; r = 0.79) but not in adenocarcinoma (N = 9; r = 0.30) and benign pulmonary disease (N = 14; r = 0.44). It is suggested that serum sialyltransferases and fucosyl transferases would not be decisive for diagnosis when used alone in bronchial carcinoma, but could be included in a screening test battery.

Bronchial Neoplasms↗
PubMed1983

Cerebrospinal fluid markers in relation to outcome in patients with global cerebral ischemia.

To investigate the possibility of improving the accuracy of prognostication in early hypoxic brain damage, 12 patients with global cerebral ischemia (GCI) due to circulatory arrest outside hospital were followed until death or for 1 yr. Five who survived for more than 2 weeks displayed better values on coma scoring from 16 h-3 days, compared to those who succumbed within 2 weeks. In 2 week-survivors, lumbar puncture revealed consistently lower adenylate kinase (AK) activity in cerebrospinal fluid (CSF) at 24 h than in the other patients, whereas glutathione and lactate values overlapped to some degree. The CSF-AK activity at 48--72 h was less correlated to clinical outcome. It is concluded that the results from coma scoring, based upon clinical observation, and from determination of AK activity in CSF at 24 h reinforce each other in discriminative power to predict prognosis in these patients.

Adenylate Kinase↗
PubMed1983

Myocardial energy restoration of ischemic damage by administration of phosphoenolpyruvate during reperfusion. A study in a paracorporeal rat heart model.

The myocardial energy restoration of ischemic damage by administration of phosphoenolpyruvate during reperfusion was investigated in a paracorporeal heart model modified in the rat. Excised hearts were subjected to 15 min of complete global ischemia at ischemia at 37 degrees C before pulsatile blood reperfusion for 30 min. One group (n = 7) was supplemented with 67 mumol of phosphoenolpyruvate and 0.67 mumol of adenosine triphosphate dissolved in 10 ml of saline and another with plain saline (nonsupplemented) during reperfusion. All hearts were freeze-clamped after 30 min of reperfusion and subjected to energy content analysis. The adenylate charge potential was 0.91 +/- 0.01 (mean +/- SD) for the supplemented and 0.85 +/- 0.06 (mean +/- SD) for the nonsupplemented group. This difference was significant (p less than 0.02). Concomitantly the outflow of creatine kinase was less for the supplemented group. The translocation of phosphoenolpyruvate into the myocardial cells seems possible by blood supplementation of a lower dose of adenosine triphosphate.

Adenosine Triphosphate↗