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Biomedical subjects

A Ruokonen

Publications and source records attributed to A Ruokonen.

At least 55 records · Page 3Linked to original sources

Magnesium substitution in elective coronary artery surgery: a double-blind clinical study.

Magnesium may be beneficial in the control of ventricular ectopy and supraventricular tachyarrhythmias after coronary artery bypass graft (CABG) surgery, but it is not known whether a high-dose magnesium regimen is superior to a regimen keeping the patient normomagnesemic. A prospective randomized and double-blind clinical comparison was performed in 81 elective CABG patients in order to assess the effects of two different magnesium infusion regimens on electrolyte balance and postoperative arrhythmias. Forty-one patients (high-dose group, H) received 4.2 +/- 0.7 g (mean +/- SD), of magnesium sulfate before cardiopulmonary bypass, followed by an infusion of 11.9 +/- 2.8 g of magnesium chloride until the first postoperative (PO) morning, and a further 5.5 +/- 1.0 g until the second PO morning. Forty patients (low-dose group, L) received magnesium sulfate only after bypass to a total of 2.9 +/- 0.5 g at the first, and 1.4 +/- 0.1 g at the second PO morning. A blood cardioplegia technique was used in both groups, including bolus doses of magnesium chloride to a total of 2.4 +/- 0.6 g and 2.3 +/- 0.6 g to H and L patients, respectively. Continuous Holter tape-recording was used for 12 to 15 hours preoperatively, and for 48 hours postoperatively. Serum magnesium peaked in H patients on the first PO morning at 1.60 +/- 0.25 mmol/L, whereafter it declined to the normal level on the third PO morning. Patients in the L group were normomagnesemic, except after the start of bypass.(ABSTRACT TRUNCATED AT 250 WORDS)

Arrhythmias, Cardiac↗

Amino acid-enriched glucose-insulin-potassium infusion improves hemodynamic function after coronary bypass surgery. A double-blind study in patients with unstable angina and/or compromised left ventricular function.

OBJECTIVE: The goal of this study was to assess the effects of a combination of glucose-insulin-potassium (GIK) and the amino acids aspartate and glutamate upon perioperative hemodynamics in coronary surgery patients with unstable angina and/or compromised left ventricular function. DESIGN: Prospective, randomized, and double-blind clinical study. SETTING: Operating theatre and intensive care unit (ICU) of a university hospital. PATIENTS: 44 coronary artery bypass graft (CABG) patients with unstable angina and/or compromised left ventricular function. INTERVENTIONS: 22 patients (group A) were given 1l of an infusion with 250g glucose, 100 I.U. fast-acting human insulin, 72 mmol potassium, 32 mmol magnesium, 20 mmol phosphate, 65 mmol aspartate, and 65 mmol glutamate, while another 22 patients (group C) were given 1l of an infusion with 50 g glucose, 72 mmol potassium, 32 mmol magnesium, and 8 mmol phosphate. The infusion rate was 1.2 ml/kg/h from the anesthesia induction onward to the commencement of cardiopulmonary bypass, when it was reduced to 0.8 ml/kg/h. When 11 had been infused, but not later than 4 a.m., the infusion was continued by giving 10% glucose at the same rate to both groups. Additional insulin (median: 14.2 I.U., range: 0-41.5) or saline was given during bypass to the A and C patients, respectively. A blood cardioplegia technique containing aspartate and glutamate was used in both groups. RESULTS: At aortic cannulation, the cardiac index (CI) had increased from the pre-anesthetic level by 15.3% (mean) (SD: 31.7%) in group A and decreased by 7.7% (15.1%) in C patients, p = 0.0069. Also the changes in stroke index (SI; p = 0.022), left (LVSWI; p = 0.0037) and right ventricular stroke work index (RVSWI; p = 0.0097) were more favorable in group A. Despite longer aortic cross-clamp, p = 0.031, and perfusion times, p = 0.042, in A patients, the change in cardiac index was also better in this group after bypass: At decannulation, the difference between mean values was 31.8%, p = 0.0001, and at arrival in the ICU it was 16.1%, p = 0.028. The same was also seen 8 h postoperatively and on the 1st and 2nd postoperative mornings; p = 0.034, 0.040, and 0.037, respectively (Wilcoxon test). Favorable changes were seen for the A patients also regarding SI at decannulation (p = 0.0002) and after 8 h (p = 0.017); LVSWI at decannulation (p = 0.0002), at arrival in the ICU (p = 0.0023), and after 8 h (p = 0.0011); and RVSWI at decannulation (p = 0.0027), at the ICU (p = 0.021), after 8 h (p = 0.014), and on the 1st postoperative morning (p = 0.039). However, the response to a hemodynamic loading test (6% hydroxyethyl starch 5 ml/kg) was similar in the 2 groups, and there was no difference in the need for inotropic support. CONCLUSIONS: Amino acid-enriched GIK infusion improves hemodynamic function in CABG patients with unstable angina and/or compromised left ventricular function.

Aged↗

Neuroendocrine responses to real and simulated BA Hawk MK 51 flight.

The effects of psychological workload on the plasma levels of eight neuroendocrine hormones were studied in 5 undergraduate and 5 senior military pilots of the Finnish Air Force (FAF). All subjects performed the same short-term basic flight mission, which included the following: 1) start; 2) ILS-approach in minimum weather conditions; 3) visual approach; and 4) landing. The mission was performed twice: first with the BA Hawk MK 51 simulator with minimal G-forces and after that with a BA Hawk MK 51 jet trainer with Gz-forces below +2. Blood samples were collected 30 min before and 10 min after the mission and were measured for adrenaline, noradrenaline, ACTH, beta-endorphin, prolactin, vasopressin (AVP), atrial natriuretic peptide (ANP), and cortisol. The plasma levels of adrenaline, noradrenaline, ACTH, beta-endorphin, and cortisol did not change significantly in response to simulated or real flight. Plasma prolactin levels increased significantly (p = 0.037) in all subjects after the mission performed with jet trainer, and the increase was especially great in cadets. However, the same mission performed with the simulator did not raise plasma prolactin levels. This finding suggests that the psychological workload in a flight simulator does not correspond to the psychological workload in a real jet trainer, at least not in basic flying. Plasma AVP increased significantly (p = 0.032) after the mission performed with the simulator in cadets; this increase can be described as a "first-time effect." Plasma ANP also increased significantly (p < 0.05) after a real jet trainer flight.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Maturation of vaginal and endometrial epithelium in postmenopausal breast cancer patients receiving long-term tamoxifen.

To assess the estrogenic effects of tamoxifen on vaginal and endometrial epithelium and to investigate whether these changes are associated with any pathological findings in the endometrium, 53 postmenopausal breast cancer patients receiving long-term tamoxifen and 52 control breast cancer patients without any hormonal treatment were examined. Pathological findings in the endometrium were evaluated by hysteroscopy and curettage. The main outcome measures were the maturation index in Papanicolaou (Pap) smears, estrogen-like epithelial changes in the endometrium, serum concentrations of gonadotropins, sex hormone-binding globulin (SHBG), estradiol (E2), and testosterone (T). Informative Pap smears showed estrogenic effects in 89% (41/46) of the tamoxifen group and in 49% (22/45) of the control group, and in endometrial aspiration samples in 71% (32/45) and in 41% (19/46), respectively. These changes were associated with increased concentrations of serum E2 in the control group but not in the tamoxifen group. All five patients (11%) with endometrial polyps in the control group showed estrogenic endometrial changes, whereas among 14 women with polyps in the tamoxifen group, 9 showed estrogenic changes and 5 endometrial atrophy. Endometrial adenocarcinoma was found in 3 patients in the tamoxifen group and in 2 in the control group. Pap smears showed atrophy in 2 patients in the former and in one in the latter group. These findings confirmed estrogen-like effects of tamoxifen on the vaginal and endometrial epithelium in postmenopausal breast cancer patients, but these were not closely associated with benign or malignant endometrial lesions.

Adenocarcinoma↗

Perioperative glucose-insulin-potassium infusion in elective coronary surgery: minor benefit in connection with blood cardioplegia?

OBJECTIVE: The goal of this study was to examine the metabolic and hemodynamic effects of a glucose-insulin-potassium infusion in elective coronary surgery, when blood cardioplegia was used for cardiac protection. DESIGN AND PATIENTS: A prospective, randomized, open, clinical comparison was performed between 2 perioperative infusion regimens in 40 elective nondiabetic coronary artery bypass graft (CABG) surgery patients. SETTING AND INTERVENTIONS: 20 patients (glucose-insulin-potassium-GIK-group) received glucose 0.2 g/kg/h, insulin 0.12 U/kg/h, potassium 0.15, magnesium 0.032 and phosphate 0.024 mmol/kg/h from anesthesia induction to the start of bypass, when infusion rate was reduced to 30%, and after bypass increased to 50% of the initial rate. The infusion was continued until the first postoperative morning. Another 20 patients (control-R-group) received glucose 0.05 g/kg/h, potassium 0.075, magnesium 0.016 and phosphate 0.008 mmol/kg/h from the end of bypass to the next morning. Pump prime was glucose-free and a blood cardioplegia technique was used for cardiac protection. RESULTS: The GIK patients needed less dopamine support in the intensive care unit (ICU) (p < 0.05). No difference was found between the groups with regard to myocardial injury, the MB-fractions of serum creatine kinase (CK-MB) being elevated to a similar degree in both groups. Likewise there were no significant differences in hemodynamic changes or duration of ICU stay. Although the glucose infusion was continued during bypass in the GIK patients, there was a considerable risk of hypoglycemia (due to insulin and hemodilution) after the onset of bypass: in 5 GIK patients (25%; 95% confidence interval 8.7 to 49.1%) blood glucose was less than 2 mmol/l. However, the hypoglycemia was of short duration and no detrimental effects were seen. CONCLUSIONS: Perioperative GIK infusion entailed a slight decrease in the postoperative need for dopamine support, but was connected with a considerable risk of hypoglycemia.

Adult↗

Effect of growth hormone administration on human ovarian function and steroidogenic gene expression in granulosa-luteal cells.

OBJECTIVE: To study the effect of growth hormone (GH) in combination with an ultrashort-term gonadotropin-releasing hormone analogue/human menopausal gonadotropin (hMG)/human chorionic gonadotropin (hCG) regimen in ovarian hyperstimulation for in vitro fertilization (IVF). DESIGN: Prospective randomized placebo-controlled study. SETTING: University-based IVF program. PATIENTS: Fifty-four normally cycling women (27 control and 27 GH-treated) participated in this study. INTERVENTIONS: Human recombinant GH (24 IU)/placebo was given intramuscularly on alternate days starting on cycle day 4 until the day of last hMG injection. RESULTS: Serum estradiol (E2) and progesterone (P) concentrations were slightly lower in the GH group than in the placebo group on the day of hCG injection and 1 day thereafter (P < 0.01 to 0.001). Serum luteinizing hormone, follicle-stimulating hormone, prolactin, testosterone (T), and sex hormone-binding globulin did not differ between the groups. The follicular fluid (FF) concentration of T was higher in the GH group than in the placebo group (15.9 +/- 6.0 nmol/L versus 10.2 +/- 4.9 nmol/L, P < 0.005), and no differences were observed in the FF concentrations of E2, P, and insulin-like growth factor I between the groups. In granulosa cells isolated from patients who received GH treatment, the levels of 3 beta-hydroxysteroid dehydrogenase and aromatase messenger ribonucleic acid were significantly higher than in the patients receiving placebo. The number of hMG ampules needed for follicular development and the number of follicles and oocytes recovered were similar in both groups. CONCLUSIONS: These results indicate that GH administration modifies ovarian steroidogenic response to gonadotropins in IVF patients, suggesting a role for GH in the regulation of human ovarian function.

Adult↗

Fumarase deficiency: two siblings with enlarged cerebral ventricles and polyhydramnios in utero.

A family having two boys with progressive encephalomyopathy and fumaric aciduria due to fumarase deficiency is described. Both patients initially presented with polyhydramnios and enlarged cerebral ventricles in utero, with subsequent cerebral atrophy, severe developmental delay, infantile spasms, and hypsarythmia on electroencephalogram. Fumarase activity in blood mononuclear cells and in the mitochondrial and cytosolic fractions of cultured skin fibroblasts was less than 0.5% of the control mean or undetectable. The older boy died at the age of 5 years and 4 months and the younger one is now 2 years and 10 months. The unrelated parents are symptomless and the other three children in the family are clinically healthy. Fumarase activities in the blood mononuclear cells of the father, mother, sister, and two brothers were 59%, 52%, 52%, 120%, and 44% of the control mean, respectively. The results strongly support autosomal recessive inheritance of fumarase deficiency and suggest its consideration in children with congenital hydrocephalus, progressive brain atrophy, and infantile spasms.

Cells, Cultured↗

Gonadotropin pulsatility in a stimulated cycle: clomiphene citrate increases pulse amplitudes of both luteinizing hormone and follicle-stimulating hormone.

OBJECTIVE: To elucidate gonadotropin secretory patterns during ovarian hyperstimulation for in vitro fertilization. DESIGN: All volunteers who attended the unit during a period of 3 months were prospectively investigated. SETTING: Infertility unit of the University Central Hospital of Oulu. PARTICIPANTS: Normally menstruating tubal infertility patients (n = 8) and healthy women with ovulatory cycles (hospital personnel, n = 11). All patients finished the study. INTERVENTIONS: Clomiphene citrate (CC), 50 mg, was administered on cycle days 5 to 9 and 300 IU of pure follicle-stimulating hormone (FSH) on cycle day 7 and 150 IU on cycle day 8. MAIN OUTCOME MEASURES: Serum samples for luteinizing hormone (LH) and FSH measurements were collected at 10-minute intervals for 6 hours on cycle day 7 (effect of CC) and day 9 (effect of CC/FSH), and the data were analyzed with the Munro computer program. RESULTS: The number of LH peaks was identical in the controls and study subjects on cycle days 7 and 9, whereas the pulse amplitude (P less than 0.025) and the pulse area (P less than 0.01) were higher in the CC/FSH-treated patients. The increase in overall mean LH level during the hormone therapy was not significant. In the CC/FSH-treated women, a decreased number of FSH pulses (P less than 0.01) with increased amplitude (P less than 0.001) and pulse area (P less than 0.01) was found. Clomiphene citrate treatment increased the mean FSH level (control versus cycle day 7, P less than 0.05) which was further increased (cycle day 7 versus cycle day 9, P less than 0.05) by FSH administration on cycle days 7 to 8. Otherwise pure FSH was found to be unable to modify endogenous LH or FSH secretory patterns under these conditions. CONCLUSIONS: Clomiphene citrate increases the amplitudes of both LH and FSH pulses in the midfollicular phase of a stimulated cycle, an effect which is not influenced by pure FSH administration.

Adult↗

Effective clinical response to long term octreotide treatment, with reduced serum concentrations of growth hormone, insulin-like growth factor-I, and the amino-terminal propeptide of type III procollagen in acromegaly.

Ten patients with active acromegaly, six with a poor response to previous therapies and four newly diagnosed, were treated with the long-acting somatostatin analog octreotide (Sandostatin; 200-500 micrograms/day, sc, twice or three times daily) for 6-15 months. There was rapid clinical improvement in all patients. The mean daily serum GH concentration was reduced by 64% and was normalized (all GH values less than 2 micrograms/L) in three patients. Serum insulin-like growth factor-I (IGF-I) concentrations were lowered by 40% and were normalized in eight patients. Serum concentrations of the amino-terminal propeptide of type III procollagen (PIIINP), an index of tissue collagen metabolism, were reduced by 40% and were normalized in all patients with initially elevated values. There was a statistically significant positive correlation between the mean serum GH and IGF-I levels (r = 0.47; P less than 0.001) as well as between serum GH and PIIINP levels (r = 0.34; P less than 0.05) and between serum IGF-I and PIIINP (r = 0.50; P less than 0.001). The effects of octreotide on pituitary tumor size and pathology were evaluated in one patient. The therapy did not seem to be associated with significant changes in sellar computed tomographic scans or light microscopic findings. The drug was generally well tolerated. However, indications of significant hepato-biliary dysfunction were noted in one patient after 5 months of therapy. This was reversible upon discontinuation of therapy and did not occur later during the rechallenge with a lower dose of the drug. However, there was probably newly formed cholelithiasis in four patients during the therapy. Our study suggests that octreotide is an effective and relatively safe new approach for treating active acromegaly. Further studies are needed to investigate long term effects on the hepatobiliary system.

Acromegaly↗

Prenatal diagnosis of single gene disorders in northern Finland.

Prenatal diagnosis of single gene disorders is challenging because of the multidisciplinary diagnostic approach and the genetic counselling needed. Out of 3100 pregnancies of northern Finnish women studied for early detection of congenital defects or genetic disease, 110 were at risk for and 15 were unexpectedly found to carry a fetus with a single gene disorder. Seven of the 21 diseases studied were typically representative of inherited diseases in northern Finland. The diagnostic approaches used included fetal ultrasonography, analysis of the components of the amniotic fluid, fetal enzyme analysis, fetal karyotyping for the fragile X syndrome, and fetal DNA analysis. Altogether, 50 pregnancies were found to be affected; 11 of these were continued because the diagnosis was too late for termination, and seven because the parents wanted it. Prenatal diagnosis of severe hereditary disease can be enhanced by improving the detection of pregnancies at risk, and by developing methods for earlier fetal diagnosis.

Adult↗

Effects of thyroid hormones (T4,T3), bromocriptine and Triac on inappropriate TSH hypersecretion.

Inappropriate TSH hypersecretion was diagnosed in a 38-year-old woman (case 1) and in a 38-year-old man (case 2). Both of them had earlier been treated by ablative therapy for hyperthyroidism. The present diagnosis was based on elevated basal serum TSH levels despite elevated serum free thyroid hormone levels. Both of them had exaggerated TSH responses to TRH (peak value 240 mU/l in case 1 and 408 mU/l in case 2). Their albumin and prealbumin levels were normal. The serum TBG level was normal in case 1 but was elevated in case 2. Serum levels of alpha-subunits of TSH, and pituitary CT scans were normal. Despite mild clinical hyperthyroidism, peripheral indices of thyroid hormone action were normal. They had also relatives with apparent resistance to thyroid hormones. In view of the possibility that prolonged pituitary thyrotrophic stimulation is detrimental, various therapeutic approaches to suppress TSH levels were tried. Both T3 and T4 treatments lowered serum TSH levels, but were poorly tolerated. Acute administration of L-dopa or bromocriptine reduced serum TSH levels, but this was not seen during long-term therapy. TRIAC treatment lowered serum TSH levels, and the drug was well tolerated. Serum TSH responses to TRH were not blunted during T3, T4 or TRIAC treatments. Somatostatin also reduced serum TSH levels, but did not potentiate the effect of low dose T3 therapy. Our results suggest that the patients had unbalanced pituitary and peripheral thyroid hormone resistance, predominantly at the pituitary level. Of the drugs studied, TRIAC seemed to be the most suitable therapy.

Adult↗

Hormonal and clinical effects of ketoconazole in hirsute women.

The effects of ketoconazole on pituitary-ovarian function and adrenal function were evaluated in nine hirsute women treated with 400-1200 mg/day for 1-6 months. High dose (800-1200 mg/day) ketoconazole treatment decreased serum androstenedione, dehydroepiandrosterone, and testosterone (T) concentrations, while that of 17 alpha-hydroxyprogesterone increased, suggesting a steroidogenic block at the level of 17,20-desmolase. The decreased serum T and increased sex hormone-binding globulin concentrations led to a significant decrease in the free androgen index. Serum estradiol, cortisol, and dehydroepiandrosterone sulfate concentrations did not change. The serum LH concentration and the LH to FSH ratio increased during treatment, suggesting a negative feedback effect of T on pituitary LH secretion. The hormonal changes that occurred during high dose ketoconazole therapy persisted during subsequent low dose (400 mg/day) treatment. The therapeutic effect of ketoconazole on hirsutism manifested itself at 6 months. We conclude that ketoconazole reduces excessive androgen production in a dose-dependent manner and decreases the free androgen index in hirsute women; these changes are accompanied by significant alleviation of hirsutism.

Adult↗

Effect of clomiphene citrate on prolactin and gonadotropin release during GnRH-analog treatment.

The capacity of the anterior pituitary to secrete prolactin (PRL) and gonadotropins was evaluated by TRH and GnRH stimulation, followed by metoclopramide (MC) administration 1 hour later, before and after clomiphene citrate (CC) priming in 8 endometriosis patients receiving GnRH agonist analog (Buserelin) therapy for 6 months. GnRH-analog treatment lowered the maximal PRL responses to TRH and MC stimulation in the luteal phase, compared to those of 8 normally menstruating control patients. The LH response to GnRH stimulation was also diminished, indicating pituitary desensitization, while the FSH response remained unchanged. Antiestrogen administration during GnRH-analog treatment further reduced the capacity of pituitary lactotropes to secrete PRL in TRH and MC tests, and it increased the LH response but not the FSH response to GnRH stimulation. These data suggest that CC affects the mechanisms controlling PRL and gonadotropin secretions in hypoestrogenic women after prolonged GnRH agonist analog treatment by different modes of action, the action on gonadotropes being stimulatory and that on lactotropes inhibitory.

Adult↗

Anterior pituitary dysfunction during the luteal phase following ovarian hyperstimulation.

The capacity of the pituitary to secrete prolactin (PRL) and gonadotropins was investigated during the luteal phase of eight normally menstruating tubal infertility patients after ovarian stimulation with clomiphene citrate, human menopausal gonadotropin, and human chorionic gonadotropin. The baseline values of PRL were significantly higher (P less than 0.025), those of luteinizing hormone unchanged, and those of follicle-stimulating hormone lower (P less than 0.025) during the treatment than in the control cycles. The maximal response of PRL to the dopamine antagonist metoclopramide was increased (P less than 0.01), whereas the maximal responses of luteinizing hormone (P less than 0.025) and follicle-stimulating hormone (P less than 0.001) to gonadotropin-releasing hormone were lowered in the treatment cycles. The current results indicate that ovarian hyperstimulation with clomiphene citrate/human menopausal gonadotropin/human chorionic gonadotropin may induce luteal phase pituitary dysfunction, which may affect the luteal phase functions of the corpus luteum.

Adult↗

Isolated prolactin deficiency in a woman with puerperal alactogenesis.

Idiopathic PRL deficiency was detected in a parturient woman with otherwise normal pituitary function. This PRL disorder first became manifest postpartum when she had no milk production, and oral metoclopramide failed to raise her serum PRL levels. Her second pregnancy occurred spontaneously after 3 yr of attempts to conceive. During the pregnancy, her serum PRL concentration was very low, varying from 4.5-7.8 ng/ml, and the puerperium was again characterized by alactogenesis. During normal menstrual cycles and after iv GnRH, TRH, metoclopramide, and insulin tolerance tests, serum PRL was only rarely detectable by RIA, at very low concentrations. Bioassay results confirmed the PRL deficiency. The results confirm that PRL is necessary for puerperal lactation and suggest that it is needed for normal ovarian function. The present data also suggest that the maternal pituitary is the main source of serum PRL during pregnancy, and the decidua has only a minor contribution in this respect.

Adult↗