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Biomedical subjects

A Berg

Publications and source records attributed to A Berg.

At least 181 records · Page 10Linked to original sources
PubMed1995

Development and characterization of essential fatty acid deficiency in human endothelial cells in culture.

We induced an essential fatty acid deficiency (EFAD) in human umbilical vein endothelial cells by culture in medium with 20% (vol/vol) delipidated fetal calf serum. EFAD, reflected by decreased cellular linoleic acid (18:2 omega 6) and arachidonic acid (20:4 omega 6) and emergence of the oleic acid derivative 5,8,11-eicosatrienoic acid (20:3 omega 9; Mead's acid), was evident after 1 week of culture and became pronounced after 2 weeks. Beyond that time point, control cells (cultured in 20% normal fetal calf serum) grew deficient of 18:2 omega 6, and EFAD cells died. 18:2 omega 6 addition to EFAD cells resulted in dose-dependent increases of 18:2 omega 6 and 20:4 omega 6. 20:4 omega 6 or 5,8,11,14,17-eicosapentaenoic acid (20:5 omega 3) additions resulted in normalization of these acids, and conversion of 20:5 omega 3 to 4,7,10,13,16,19-docosahexaenoic acid (22:6 omega 3) was noted. Agonist-induced increases in concentrations of prostacycline (prostaglandin I2; PGI2) and cytosolic Ca2+, [Ca2+]i, were reduced in EFAD cells and not restored by 18:2 omega 6 or 20:4 omega 6 additions. Change of the medium in EFAD cultures 1 day before the experiments decreased 20:3 omega 9 and normalized the PGI2 production and [Ca2+]i changes, whereas addition of 20:3 omega 9 to control cells impaired the [Ca2+]i response, indicating a suppressive effect of 20:3 omega 9. Thus, EFAD in endothelial cells is associated with abnormalities of eicosanoid and second-messenger production partly attributable to 20:3 omega 9 accumulation. Moreover, the gradual emergence of 18:2 omega 6 deficiency in regularly grown control cells underlines the need for careful analysis of fatty acids in long-term cell cultures.

Calcium↗
PubMed1995

Red cell folate levels in pregnant epileptic women.

Red cell folate concentrations were determined in 74 epileptic women in early pregnancy in a prospective study. All patients were treated continuously with antiepileptic drugs since before conception. The most frequently used drugs were carbamazepine (n = 39) and phenytoin (n = 26). Sixty-four patients (86%) were on monotherapy. Blood samples for red cell folate and antiepileptic drug concentrations were drawn before folate supplementation. Red cell folate levels in patients, 468 nmol.l-1, did not differ from those in non-epileptic, drug-free, pregnant women, 416 nmol.l-1 or from those in non-pregnant age-matched healthy controls, 412 nmol.l-1. No correlation was found between red cell folate concentrations and doses or plasma levels of phenytoin or carbamazepine.

Adult↗
PubMed1995

Analysis of a whole arm translocation between chromosomes 18 and 20 using fluorescence in situ hybridization: detection of a break in the centromeric alpha-satellite sequences.

Using classical cytogenetic techniques, we detected a male patient with monosomy 18p/trisomy 20p, originating from a paternal reciprocal translocation of the short arms of chromosomes 18 and 20. To characterize the breakpoints further and to determine the centromeric origin of the chromosomes involved, we analyzed the metaphase chromosomes by fluorescence in situ hybridization using alpha-satellite DNA probes specific to chromosomes 18 and 20. With this approach, we showed that alpha-satellite centromeric fragments were involved in the translocation event and that the chromosome-18-specific centromeric sequences were split into two. Analysis of 14 family members from four generations revealed nine phenotypically normal individuals carrying this reciprocal translocation. These results suggest that breaks in alpha-satellite DNA fragments neither impair the centromeric function nor have clinical effects.

Abnormalities, Multiple↗
PubMed1995

Gastroesophageal reflux after repair of congenital diaphragmatic hernia.

Seventy-four survivors of congenital diaphragmatic hernia (CDH) repair were reviewed for gastroesophageal reflux (GER). Twenty-nine patients had a prenatal diagnosis of CDH, 31 had the diagnosis established during the first 60 minutes of life, and 14 had a late diagnosis. Fifty-seven of the 60 patients with a prenatal diagnosis or diagnosis at birth had their CDH repaired during the first 24 hours of life. Thirty-six of the 37 patients with clinical signs of GER and 10 patients without typical clinical signs had documented GER. The overall incidence of GER was 62% (46 of 74). The 46 comprised 22 of the 29 patients (75.8%) with a prenatal diagnosis of CDH, 21 of the 31 (67.7%) with a diagnosis at birth, and 3 of the 14 with a late diagnosis. Eleven patients had surgical treatment of GER. A significant correlation was found between GER and the preoperative thoracic position of the stomach (32 v 8, GER+ v GER-; P < .01) and GER and the prenatal diagnosis of CDH (22 v 7, GER+ v GER-; P < .01). Duration of artificial ventilation (68.97 +/- 15.33 days v 14.14 +/- 3.89 days, GER+ v GER-; P < .005) and duration of hospitalization (22.04 +/- 3.59 weeks v 3.9 +/- 0.88 weeks, GER+ v GER-; P < .0003) were significantly longer for the patients with pathological GER. To decrease the morbidity related to GER, we propose using diaphragmatic patches during hernia repair to lower the strain on the crus, and using parietal patches to lower intraabdominal pressure after reintroduction of the herniated viscera.

Female↗
PubMed1995

Relationship between obesity and concentration and composition of low-density lipoprotein subfractions in normoinsulinemic men.

Obesity, insulin resistance (IR) with hyperinsulinemia, and a dyslipoproteinemia characterized by reduced high-density lipoprotein 2 (HDL2) cholesterol and elevated levels of small, dense low-density lipoprotein (LDL) particles are risk factors for coronary artery disease (CAD). The impact of obesity independent of hyperinsulinemia on the concentration and composition of small, dense LDL subfractions is uncertain. The aim of this study was to investigate the relationship between obesity indices, namely body mass index (BMI), skinfold measurements (SF), and waist to hip ratio (WHR), and LDL-subfraction particle concentration and composition in 200 healthy men without evidence of IR. A precise analysis of the concentration of lipids and apolipoproteins and the composition of very-low-density lipoprotein (VLDL), intermediate-density lipoprotein (IDL), and two HDL- and six LDL-subfraction particles was obtained using the technique of density-gradient ultracentrifugation. Dividing the individuals according to BMI showed that those with a BMI greater than 27 kg/m2 had significantly lower HDL2 cholesterol and apolipoprotein (apo) A-I and higher VLDL and IDL cholesterol and apo B concentrations than those with a BMI less than 25 kg/m2. Regarding LDL particles, we found that men with a BMI above 25 kg/m2 had significantly more small, dense LDL particles (d 1.044 to 1.063 g/mL) and correspondingly fewer medium, dense LDL particles (d 1.031 to 1.037 g/mL) than leaner men; those with a BMI above 27 kg/m2 had the highest concentration of circulating small, dense LDL particles. These findings were not influenced by fasting insulin concentrations, IR, or WHR.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

EEG and seizure outcome after epilepsy surgery.

The significance of the EEG after epilepsy surgery is not fully understood. We investigated the association between postoperative EEG abnormalities and persistent seizures after epilepsy surgery as they relate to pathologic lesions. Among 254 patients who underwent epilepsy surgery between 1987 and 1991, we identified 78 patients who had mesiotemporal sclerosis (MTS) and 47 patients who had low-grade brain tumors, all of whom had 6- to 18-month postoperative follow-up including EEG. Patients who had other pathology, multiple operations, callosotomy, or hemispherectomy, or who were aged < 18 years or who had insufficient EEG data, were excluded. Patients were classified as having persistent seizures or being seizure-free since operation. EEG abnormalities were abstracted from EEG reports 6-18 months postoperatively. Seizures persisted in 24% of the MTS group and in 27% of the tumor group. Of those with normal EEGs, none of the MTS patients and only 1 of the tumor patients had persistent seizures (p = 0.03 for MTS and p = 0.42 for tumor). Epileptiform discharges and focal slowing were associated with seizure persistence in both groups, but to a significant extent only in the MTS group. In the MTS group, patients who had both epileptiform discharges and focal slowing were more likely to have persistent seizures than were those with either abnormality alone.

Adult↗
PubMed1995

[Life style changes in patients with myocardial infarct in the framework of intramural and ambulatory rehabilitation--results of a German pilot study].

To assess whether German patients would make comprehensive lifestyle changes as designed and successfully tested in the San Francisco Lifestyle Heart Trial, we recruited 25 patients who received usual care, and 15 patients who made lifestyle changes during a 6-week in-hospital rehabilitation program followed by a 3-month ambulatory period. The intervention program consisted of a low-fat vegetarian diet, stress management techniques, aerobic exercises, and group support meetings. The program was well accepted, and high compliance resulted in significant changes in the patients' diet, stress management, and exercise activity. For instance, fat intake dropped from 36% to 9% of total calories. As patients in both groups received 20 mg/day of Pravastatin, a lipid-lowering drug, lipid levels dropped significantly in both groups (30% in the intervention group and 27% in the control group). Thus, the combined effect of behavioral and drug treatment did not result in a substantial additional lipid-lowering effect. Within the intervention group significant improvement in quality of life occurred. In conclusion, the lifestyle heart program can be successfully implemented in a German rehabilitation setting which combines in-hospital and out-patient activities. However, participation in the current program is limited to highly motivated, well educated coronary patients.

Adult↗
PubMed1995

[Assessment and evaluation of leisure activity of participants in heart rehabilitation groups].

A self-administered questionnaire was used to assess leisure-time physical activity (LTPA) of patients participating in cardiac rehabilitation groups (CHD: n = 144, 115 male, 29 female) and an age-matched control group (CG: n = 100, 76 male, 24 female). The mean times spent on LTPA per week were 12.2 h (CHD) and 13.3 h (CG); this difference was due to the fact that participants of the cardiac rehabilitation groups were less engaged (1 h) in sports activities (12% contribution to LTPA versus 19.5%). The results show that most of the CHD patients organized in the groups achieved LTPA levels and energy turnover rates which are thought to have beneficial effects on the course of the atherosclerotic coronary disease. Participants who did not reach the critical energy turnover threshold should be paid particular attention with regard to their educational, as well as their medical needs.

Adult↗
PubMed1994

Sequential 1H and 15N nuclear magnetic resonance assignments and secondary structure of the N-terminal lipoyl domain of the dihydrolipoyl transacetylase component of the pyruvate dehydrogenase complex from Azotobacter vinelandii.

The N-terminal lipoyl domain (79 residues) of the transacetylase component of the pyruvate dehydrogenase complex from Azotobacter vinelandii has been sub-cloned and produced in Escherichia coli. Over-expression exceeds the capacity of E. coli cells to lipoylate all expressed lipoyl domain, but addition of lipoic acid to the growth medium results in expression of fully lipoylated domain. A two-dimensional homo- and heteronuclear NMR study of the lipoyl domain has resulted in sequential 1H and 15N resonance assignments of the unlipoylated form of the protein. Small differences in chemical shift values for protons of residues in the vicinity of the lipoyl-lysine residue are observed for the lipoylated form of the domain, suggesting that the conformation of the lipoyl domain is not altered significantly by the coupled cofactor. From nuclear Overhauser effects, backbone coupling constants and slowly exchanging amide protons, two antiparallel beta-sheets, each containing four strands, were identified. The lipoyl-lysine residue is exposed to the solvent and located in a type-I turn between two strands. The N- and C-terminal residues of the folded chain are close together in the other sheet. Preliminary data on the relative three-dimensional orientation of the two beta-sheets are presented. Comparison with the solution structure of the lipoyl domain of the Bacillus stearothermophilous pyruvate dehydrogenase complex shows resemblance to a large extent, despite the sequence identity of 31%.

Acetyltransferases↗
PubMed1994

Nurses' creativity, tedium and burnout during 1 year of clinical supervision and implementation of individually planned nursing care: comparisons between a ward for severely demented patients and a similar control ward.

The aim of this study was to study creativity and innovative climate, tedium and burnout among the nurses on two wards during 1 year of systematic clinic supervision combined with the implementation of individualized care on an experimental ward (EW) for severely demented patients, as compared with a similar control ward (CW). EW nurses had systematic clinic supervision and each patient had his/her nursing care carefully planned, documented and evaluated. The intervention was evaluated by means of the Creative Climate Questionnaire, Burnout Measure and the Maslach Burnout Inventory. Creativity and innovative climate improved significantly among the EW nurses (n = 19) in eight out of 10 factors during the year of intervention while there was no change on the control ward (n = 20). Tedium and burnout decreased significantly among the EW nurses while no change was seen in this respect among the CW nurses. It seems reasonable to assume that systematic clinical supervision and individualized planned care decreases the negative outcome of stress caused by the psychological burden imposed by nursing care. It also increases nurses' creativity, which, in turn, may benefit patient care. The findings of this study point to the necessity for a support system that focuses on the work itself, i.e. the nursing care. Individualized planned care and systematic clinical supervision may offer this kind of support.

Adult↗
PubMed1994

The cytokine response to strenuous exercise.

Several groups have now investigated the cytokine response to strenuous exercise. In this article we try to summarize known data on this topic. Significant, albeit mild increases in plasma levels of the monokines IL-1, TNF-alpha, IL-6, and of soluble IL-2 receptor have been reported following strenuous exercise. Increased excretion of cytokines after exercise can also be shown in the urine of athletes. Modulation of cytokine release by strenuous exercise can also be demonstrated using in vitro cell cultures. Several authors have shown an increase in endotoxin-stimulated monokine release following exercise. In contrast, using whole blood cultures we found strongly depressed production of interferon gamma (in response to mitogen or endotoxin) following strenuous exercise. The potential significance of cytokine modulation for exercise-related immunological problems is discussed.

Cells, Cultured↗
PubMed1994

Stimulus-specific defect in platelet aggregation in polycythemia vera.

We have previously reported that polymorphonuclear granulocyte (PMN) and monocyte oxidative metabolism is reduced in polycythemia vera (PV) patients compared to healthy control subjects, after stimulation with cell surface receptor-dependent stimuli such as n-formyl-methionyl-leucyl-phenylalanine, leukotriene B4 and platelet-activating factor (PAF). In contrast, the oxidative response to phorbol myristate acetate (PMA) is normal. We now show that, in PV patients exhibiting significantly reduced PMN chemiluminescence after PAF stimulation, PAF induced platelet aggregation was also reduced--40 +/- 3% compared to 50 +/- 2% in controls (p < 0.01). The defective aggregatory response to PAF in PV remained over a wide range of stimuli concentrations. Platelet aggregation induced by PMA and ADP, however, was similar in PV and controls. In contrast, platelet aggregation induced by PAF (or by ADP and PMA) was not significantly reduced in patients with chronic myeloid leukemia, essential thrombocythemia and multiple myeloma. Furthermore, the release of beta-thromboglobulin was slightly but not significantly higher after PAF stimulation in PV and this argues against an abnormal PAF receptor as the cause of the defective function. Thus, not only PV neutrophils, but also PV platelets show a discrete defect of the stimulus response coupling for PAF, indicating a disease-specific abnormality that appears to be of clonal origin.

Adenosine Diphosphate↗
PubMed1994

Physical activity and lipoprotein lipid disorders.

Working muscle plays a central role in the control of lipid metabolism. Increased physical activity induces a number of positive changes in the metabolism of lipoproteins: serum triglycerides are lowered by the increased lipolytic activity and the production of native high density lipoprotein (HDL) particles is increased. The increased lecithin: cholesterol acyltransferase activity leads to an increased production of HDL2, which in addition is catabolised more slowly due to a decreased activity of hepatic lipase. The 3 effects explain the increased HDL levels of endurance trained individuals. These effects have been demonstrated in cross-sectional as well as longitudinal studies by different groups, and can be induced by training, independent of changes in bodyweight. The influence of endurance activity on the quality and quantity of low density lipoprotein (LDL) particles is a further reason for the antiatherogenic potential of increased physical activity. It has been shown by several groups that small dense LDL particles represent a particular risk factor for atherosclerosis. Recent studies presented strong evidence that LDL level and composition can be influenced favorably by physical activity. In addition to the direct influence of physical activity on lipids and lipoproteins, physical exercise may improve the disturbances of haemorheological factors, particularly those associated with hypertriglyceridaemia. In conclusion, there is increased evidence that physical activity is able to favourably influence all 3 components of the atherogenic lipoprotein phenotype: the HDL concentration increases, the concentration of small dense LDL decreases, and serum triglycerides are reduced.

Apolipoproteins↗
PubMed1994

[Polytraumatised children].

Trauma is the leading cause of mortality in children between the ages of 1 and 14 years. It represents a major health problem in all industrialized countries. A well coordinated organization of the whole chain of cares is essential, from the initial management at the scene of the accident until the long term neurological rehabilitation of the child. During the initial examination, the presence of anoxia, hypovolemia or neurological distress was systematically evaluated. Emergency therapeutic measures should be ensured. At the term of this initial management: if the haemodynamic state is unstable, an emergency operative procedure may be required; if the haemodynamic state remains stable, one can realize a complete clinical and radiological assessment. The clinical and biological supervision must continue during this evaluation while sedation and analgesia are essential to limit an increase in intracranial pressure (ICP). At the term of this complete assessment, if one or several surgical lesions are identified, an operative program with a precise hierarchy is scheduled; if an intensive medical support is required, the child is then transferred to the pediatric intensive care unit. Most often, children with a serious head trauma do not have neurosurgical lesions but a "brain-swelling" or cerebral edema. Elevated ICP is one of the main risk for cerebral ischemia. Therefore, continuous assessment of ICP is essential. Thoracic trauma is most often a closed trauma in the child: pneumothorax and pulmonary contusion are the problems most frequently met. An emergency laparotomy is required if the abdomen volume increases rapidly associated to the persistence of a unstable haemodynamic status despite an important fluid expansion. However, the presence of intraperitoneal blood is no longer a formal indication to surgery. Frequent examination of liver and splenic lesions with abdominal tomodensitometry allows to avoid surgery in more than 90% of cases at the price of a very rigorous haemodynamic supervision. Intestinal perforations are rare and difficult to diagnose: peritoneal dialysis, if it reveals the presence of a leucocytosis greater than 500/mm3 or bacteria justifies the surgery.(ABSTRACT TRUNCATED AT 400 WORDS)

Child↗
PubMed1994

[Energy and nutritional intake in young weight lifters before and after nutritional counseling].

A well-balanced diet is an essential component for the development and maintenance of physical performance. Several studies on the dietary status of power athletes have shown, that there are still problems to realize the nutritional recommendations. The purpose of the present study was to analyse the energy- and nutrient intake of 11 young weight lifters aged 14 to 17 years before and after an intensive nutritional counselling (NC). Dietary status was evaluated by 7-day-protocols filled out by the young athletes 4 weeks before and 4 weeks after the NC. Before the NC the athletes (x: age 15, height 174 cm, weight 69.5 kg, BMI 22.2 kg/m2) had a mean energy intake of 179.7 kJ/kg body weight (11.2 MJ/day). The energy percentage of carbohydrate:fat:protein was 48:37:15. The protein consumption was 1.6 g/kg of body weight and the fluid intake was 1.7 l/day. The athletes did not meet the recommendation for niacin, folic acid, vitamin E, magnesium, calcium, iodine and zinc. After the NC the athletes had a significant higher energy percentage of carbohydrate and lower energy percentage of fat. In addition a significantly higher intake of fluid, dietary fiber, vitamins and minerals was observed. This study revealed that the young weight lifters without NC fall short of nutritional recommendations. With the intensive nutritional counselling an improvement of the nutrient intake could be reached. Additional nutritional counselling for the athletes and an intensive teamwork with the coach and parents of the athletes seem necessary to develop and stabilize a good nutritional behavior.

Adolescent↗
PubMed1994

[Physical activity and eating behavior: strategies for improving the serum lipid profile of children and adolescents].

Coronary risk factors such as obesity, dyslipoproteinaemia and low physical fitness are often prevalent in childhood. In contrast, regular physical activity and healthy nutrition have been shown to be effective in primary and secondary prevention of coronary artery disease. An increment in physical activity with concomitant weight loss has a profound influence on peripheral lipoprotein metabolism and has shown to improve the atherogenic lipoprotein profile. As risk factors often track from childhood into adulthood it seems inevitable to prevent or diminish risk factors as early as possible. Therefore, intervention programmes for prevention of coronary artery disease have to be conducted in childhood. Experience from an own intervention programme of obese children has shown that the combination of intensive dietary and physical education improves physical fitness, body composition as well as lipid metabolism. Whether short-term benefits will continue into adulthood and reduce coronary artery disease in midlife will have to be shown. Nonetheless, it seems out of question that children showing risk factors such as obesity or hypercholesterolaemia will benefit from early intervention programmes when changing dietary and exercise behaviours.

Adolescent↗