PubMed Health⌕ Search

Biomedical subjects

G E Jensen

Publications and source records attributed to G E Jensen.

At least 19 recordsLinked to original sources
PubMed1998

Occupational arsenic exposure and glycosylated haemoglobin.

In a group of 40 workers occupationally exposed to arsenic (As workers) biological markers for cardiovascular diseases were studied. The median arsenic concentration in urine samples from the exposed group was 22.3 nmol of As per mmol of creatinine, while the individual maximum level was 294.5 nmol of As per mmol of creatinine. That of the reference group was 12 nmol of As per mmol of creatinine and significantly below the level of the exposed group (p < 0.001). The arsenic concentration in urine samples from colleagues of the persons working with arsenic containing products was similar to the arsenic concentration in urine samples from the As workers. The concentration of glycosylated haemoglobin (Hgb A1C) was increased in whole blood from the As workers. The level of the As workers was 5.4% (median), similar to that of colleagues (5.5%), while that of the reference group was 4.4%. The differences were significant (p < 0.001). Multiple regression analysis showed a significant connection (p = 0.034) between the concentration of Hgb A1C in whole blood and the arsenic level in urine from the As workers. The systolic blood pressure was 125 mm Hg in the As workers and 117 mm Hg in the control group. The difference was significant (p = 0.023). It is concluded that arsenic exposure has an influence on carbohydrate metabolism, increases the systolic blood pressure and finally may result in increased risk of development of cardiovascular diseases.

Adult↗
PubMed1992

Biomonitoring of genotoxic exposure among stainless steel welders.

A biosurvey in the Danish metal industry measured the genotoxic exposure from stainless steel welding. The study comprised measurements of chromosomal aberrations (CA), sister-chromatid exchanges (SCE), unscheduled DNA synthesis (UDS) in peripheral lymphocytes and serum immunoglobulin G. Environmental monitoring of welding fumes and selected metal oxides, biomonitoring of chromium and nickel in serum and urine and mutagenic activity in urine, and evaluation of semen quality were also done. Manual metal arc (MMA) welding and tungsten inert gas (TIG) welding were the dominant welding processes. A higher frequency of chromosomal aberrations, classified as translocations, double minutes, exchanges and rings, was observed in stainless steel welders than in non-welders. SCE was lower in welders working with both MMA and TIG welding than in reference persons. N-Acetoxy-N-acetylaminofluorene (NA-AAF)-induced UDS was lower in 23 never-smoking welders than in 19 unexposed never-smokers. Smoking was a confounding factor resulting in significantly higher CA, SCE, NA-AAF binding to DNA and mutagenic activity in urine. Age was also a confounder: CA, SCE, NA-AAF binding to DNA and UDS increased significantly with age. No significant correlation between SCE and CA or between CA and UDS was found. UDS decreased significantly with increasing lymphocyte count and a higher lymphocyte count was seen in MMA welders than in reference persons and in smokers than in non-smokers. Differences in the composition among lymphocytes in exposed persons compared with non-exposed are suggested. MMA welding gave the highest exposure to chromium, an increased number of chromosomal aberrations and a decrease in SCE when compared with TIG welding. Consequently improvements in the occupational practice of stainless steel welding with MMA is recommended.

Acetoxyacetylaminofluorene↗
PubMed1991

Occupational and environmental exposure to arsenic--increased urinary arsenic level in children.

The sum of concentrations of inorganic arsenic, methylarsonic acid (MMAA) and dimethylarsinic acid (DMAA) in urine from adults and children living in an unpolluted area was compared with the corresponding sum measured in urine from adults and children living in an area polluted with arsenic and in urine from persons occupationally exposed to arsenic. The median values for 22 adults and 10 children aged 3-10 years living in the unpolluted area were 9.3 and 19.8 nmol As/mmol creatinine, respectively. The corresponding ranges were 3.2-27.9 and 7.7-57.8 nmol As/mmol creatinine, respectively. The difference between adults and children was tested by Mann-Whitney's non-parametric test and found to be significant (p less than 0.0025). No significant difference was found in arsenic concentration in urine from 73 adults and 10 children living in the polluted area compared with the arsenic concentration in urine from those living in the unpolluted area. The arsenic level in urine from adult workers handling arsenic-treated wood was approximately four-fold higher (p less than 0.001), with a maximum recorded concentration corresponding to 814.9 nmol As/mmol creatinine. The arsenic levels in urine from two glass workers were nine- and two-fold higher, respectively. No significantly increased arsenic levels were found in urine from workers impregnating wood and in urine from lead accumulator workers.

Adult↗
PubMed1984

Glutathione peroxidase and reductase, glucose-6-phosphate dehydrogenase and catalase activities in multiple sclerosis.

Our previous studies have demonstrated a decreased glutathione feroxidase (GSH-Px) activity of erythrocytes and leucocytes from multiple sclerosis (MS) patients. In the present communication these activities were compared with the activities of associated enzymes (glutathione reductase (GSSG-RD), glucose-6-phosphate dehydrogenase (G-6-PD) and catalase). All enzymic activities were compared between MS patients, other neurologic patients (ON patients) and normal control individuals. Compared to data of ON patients and normal controls, in MS the ratio of GSHPx/GSSGRD in lympho- and granulocytes was significantly decreased (2 alpha less than or equal to 0.05) by 35% and 51%, respectively. The significant correlation between GSSG-RD and the GSH-Px activity (2 alpha less than or equal to 0.05, r = 0.501) found in control lymphocytes was not present in MS lymphocytes. However, the lymphocyte GSH-Px activities of controls as well as of MS correlated with the corresponding serum selenium levels (2 alpha less than or equal to 0.05, r = 0.594 and 2 alpha less than or equal to 0.01, r = 0.967, respectively). The G-6-PD activity was insignificantly increased by 41% in MS lymphocytes compared to normal control. Catalase activity was unchanged in lymphocytes but decreased 50% in MS granulocytes compared to normal control. No significant differences were found between MS and the ON group. The catalase activity of MS erythrocytes was increased by 63% (2 alpha less than or equal to 0.05) in comparison with both the normal control and ON data.

Catalase↗
PubMed1984

Gold-associated nephropathy.

Renal biopsy specimens from 11 cases of gold-associated nephropathy were studied by light, immunofluorescence, and electron microscopy. Seven biopsy specimens disclosed the typical glomerular lesions of membranous nephropathy. Four cases disclosed other patterns of glomerular injury, including minimal-change nephrotic syndrome. Although a membranous pattern of immune complex deposition is the most frequent type seen in gold nephropathy, our data indicate that other patterns of immune complex deposition may occur in renal biopsy specimens of patients receiving gold therapy.

Adolescent↗
PubMed1984

Periodic disklike structures of the adult human loop of Henle. Light and electron microscopic studies.

A total of 51 adult human kidneys was examined for the presence of the periodic disklike thickenings recently described by Belliveau in the basement membrane of the loop of Henle. These "Belliveau bodies" formed a PAS-positive rectangular lattice within the basement membrane and appeared limited to the loop of Henle. The bodies were seen in the medulla of every kidney examined but varied considerably in the frequency of their appearance from case to case. This variability did not correlate with predominant illness, organ weight, or time interval between death and autopsy. They averaged 9 to 14 micron in diameter with a horizontal and vertical periodicity of 12 and 16 micron, respectively. Although the bodies were PAS positive and diastase resistant, they did not stain with Congo red, mucicarmine, reticulin, or elastin staining techniques. Ultrastructurally, they consisted of multilaminated areas of basement membrane material. The constancy of their appearance in the material examined suggests that they are a normal anatomic feature or possibly an age-related change of the basement membrane of Henle's loop in the human kidney.

Adult↗
PubMed1983

Leucocyte glutathione peroxidase activity and selenium level in Batten's disease.

The glutathione peroxidase (GSHPx) activity was found significantly reduced in whole lymphocytes from patients suffering from Batten's disease. By means of two different procedures for isolation of subcellular fractions of lymphocytes it was possible to demonstrate an increased GSHPx activity of the particulate fractions (20.000 g-av and 105.000 g-av precipitates). However, the GSHPx activity of the supernatants was decreased. The GSHPx activity of the 20.000 g-av supernatant correlated significantly with the serum selenium content both in normal controls and in Batten's disease. A similar correlation was traced with GSHPx activity of erythrocyte haemolysate and serum selenium level in Batten's disease but not in normal controls. The GSHPx activity was also found decreased in the 20.000 g-av and 105.000 g-av supernatants of granulocytes. The abnormal subcellular distribution of GSHPx activities was related to the distribution of enzymes which were used as markers for different subcellular components. The data presented are discussed in relationship to the theory that Batten's disease is due to an increased peroxidation damaging the cellular membranes.

Adenosine Monophosphate↗
PubMed1981

Subcellular distribution of the cytochrome P-450 complex and glutathione peroxidase activity in vitamin E and essential fatty acid deficiency.

Glutathione peroxidase (EC 1.11.1.9.) (GSHPx) and P-450 activity were measured in hepatic mitochondrial and microsomal fractions from rats deficient in vitamin E and/or essential fatty acids (EFA). The data were compared to corresponding normal values. GSHPx was significantly decreased in the mitochondrial matrix from animals in all 3 deficiency states. In vitamin E deficiency, a non-significant decreased GSHPx activity was found in mitochondrial membranes. Opposite to these findings, GSHPx was significantly increased in mitochondrial membranes of EFA-deficient animals. In combined EFA and vitamin E deficiency, the mitochondrial membrane GSHPx activity was only insignificantly increased. The P-450 complex activity was not detectable in the mitochondrial matrix. In mitochondrial membranes and microsomes, the P-450 complex activity changed parallel to the GSHPx activity.

Animals↗
PubMed1981

Glutathione peroxidase activity in vitamin e and essential fatty acid-deficient rats.

Gluthathione peroxidase (EC 1.11.1.9, GSHPx) activity was measured in whole liver, in hepatic cytosol and in whole mitochondria from normal rats and from rats subjected to experimentally induced vitamin e and/or essential fatty acid (EFA) deficiency. The animals were fed and raised on the specific diets for 6 months. The GSHPx activity was significantly decreased in all samples of EFA-deficient rats. This group exhibited a significant increased 29:3omega9 content and to low 20:4omega6 content. In rats fed a vitamin E-deficient diet, the GSHP x activity was significantly decreased in hepatic cytosol. When the data of all experimental groups were pooled the specific GSHP x activities of the hepatic cytosol correlated significantly to that of whole mitochondria. The specific GSHP x activity of the whole liver, the mitochondrial and the cytosol fractions were found higher in female than in male rats in controls as well as in deficient animals. This difference was affected by the EFA deficiency. In EFA-deficient mitochondria the sex difference in enzymic activity was decreased (half of normal difference). In EFA-deficient cytosol the difference was increased (double of normal difference). However, the total hepatic GSHPx activities were not significantly higher in female than in male rats in any of the groups studied. Thus, EFA deficiency is added to the list of factors influencing the GSHPx activity. It is concluded that it is not possible to use GSHPx activity as a marker for the selenium status in domestic animals such as suggested previously. Thus, selenium is only one of the factors governing the GSHPx level.

Animals↗
PubMed1980

Leucocyte glutathione peroxidase activity and selenium level in multiple sclerosis.

In continuation of our previous studies, which demonstrated a decreased glutathione peroxidase (GSH-Px) activity of erythrocytes from multiple sclerosis (MS) patients the activity of some enzymes regulating the peroxide level (GSH-PX and glutathione reductase (GSSG-Rd)) in leucocytes and erythrocytes respectively, the selenium level of whole blood and the beta-glucuronidase activity of serum (marker of lysosomal membrane damage) were assayed in this group of patients. GSH-Px activity in lymphocytes and granulocytes from MS patients was significantly (2 alpha smaller than or equal to 0.01) decreased by 35-50%. Erythrocyte glutathione reductase activity was only insignificantly decreased in MS patients. Erythrocyte GSH-Px : GSSG-Rd ratio was 11.0 for the control group, but 8.0 for the MS group. The selenium content of whole blood and serum from Danish MS patients was normal. The selenium level in erythrocytes from Danish MS patients was however higher than the selenium level in erythrocytes from controls.

Erythrocytes↗
PubMed1979

Organochlorine compounds in adipose tissue of Greenlanders and southern Danes.

Abdominal fat tissue samples from the general population of Greenland and from southern Denmark were analyzed for o,p'-DDE and p,p'-DDE [1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene], p,p,-DDT [1,1,1-trichloro-2,2-bis(p-chlorophenyl)-ethane], o,p'-DDT and p,p'-DDD [1,1-dichloro-2,2-bis(p-chlorophenyl)ethane], lindane (1,2,3,4,5,6-hexachlorocyclohexane), aldrin (1,2,3,4,10,10-hexachloro-1,4,4a,5,8,8a-hexahydro-endo-exo-1,4:5,8-dimethanonaphthalene), dieldrin (1,2,3,4,10,10-hexachloro-6,7-epoxy-1,4,4a,5,6,7,8,8a-octahydro-endo-exo-1,4:5,8-dimethanonaphthalene), heptachlor (1,4,5,6,7,8,8-heptachloro-3a,4,7,7a-tetrahydro-4,7-methanoindene), heptachlor epoxide, and polychlorinated biphenyls (PCBs). Fat tissue from Greenlanders contained significantly higher amounts of p,p'-DDE (p less than or equal to 0.05), p,p'-DDT (p less than or equal to 0.01), and total DDT (SIGMA DDT, the sum of DDT and its metabolites) (p less than or equal to 0.01) than southern Danes. Lindane, aldrin-like residue, dieldrin heptachlor-like residue, heptachlor epoxide, and PCBs were present in adipose tissue of both groups and there were no significant differences between the groups. The p,p'-DDE level in Greenland was lower than that in the United States, eastern Europe, and India. Among Greenlanders of different ages the highest sigma DDT was found in the age group of 22-45 yr; the content of PCBs increased with age. Among southern Danes the highest sigma DDT was found in a higher age group than in Greenlanders. Among Greenlanders the content of aldrin-like residue decreased with age and that of dieldrin increased with age. A significant correlation was found (on the basis of wet weight) between p,p'-DDE and PCB content in southern Danes (p less than or equal to 0.02). The correlation between sigma DDT and PCB content was also significant in this population (p less than or equal to 0.01). These two relationships were not significantly correlated for the Greenlanders. The DDE/PCB and sigma DDT/PCB ratios were higher in Greenlanders than in southern Danes. These ratios are age-dependent and are highest in the age group 22-45 yr among the Greenlanders. A low DDE/PCB ratio and a low sigma DDT/PCB ratio have been proposed as markers for industrialization. In Greenlanders p,p'-DDE represented about 70% of sigma DDT. For southern Danes this level was about 90%. The data obtained are presented and discussed on the basis of both lipid and wet weight levels.

Adipose Tissue↗
PubMed1978

Serum fatty acids and peroxidase abnormalities in Batten's disease.

The linoleic acid content of serum lipids was measured in 10 paitents with Batten's disease and 11 healthy control subjects by gas liquid chromatography. The fatty acid patterns of serum lipids in this disease may reflect a primary or secondary deficiency in essential fatty acid (linoleic acid) probably related to a glutathione peroxidase abnormality.

Adolescent↗
PubMed1978

Biochemical abnormalities in Batten's syndrome.

The present data indicate that a group of ten patients with Batten's syndrome showed reduced activity of erythrocyte glutathione (GSH) peroxidase (Px) (glutathione: H2O2 oxidoreductase, EC 1.1.1.9.) using H2O2 as peroxide donor. Assay of erythrocyte GSHPx using H2O2, cumene hydroperoxide and t-butyl hydroperoxide as donors also makes it possible biochemically to divide Batten's syndrome into two types: (1) one type with decreased values when H2O2 and cumene hydroperoxide are used, and (2) one type with increased values when t-butyl hydroperoxide is used. Furthermore an increased content of palmitic, oleic and of eicosatrienoic acid but decreased linoleic acid content was found in serum from patients with Batten syndrome. An inverse relationship between erythrocyte GSHPx and serum eicosatrienoic acid was found in the patients. Finally normal selenium levels were found in erythrocytes, but decreased values were traced in whole blood. In normal human beings a connection was found between the erythrocyte selenium content and GSHPx activity assayed by cumene hydroperoxide as a peroxide donor.

Adolescent↗
PubMed1977

Lysosomal (leucocyte) proteinase and sulfatase levels in Dyggve-Melchior-Clausen (DMC) syndrome.

Patients with the DMC syndrome have been suggested to possess a specific sulfatase abnormality and/or to be deficient in a proteinase cleaving glycoprotein-acid mucopolysaccharide (AMP) linkage. We have previously found in DMC patients an abnormal excretion of urinary AMPs of which hyaluronic acid and chondroitin sulfate (A + C) were oversulfated and keratosulfate and heparan sulfate were undersulfated. Lysosomal acid proteinase, i.e. cathepsin D (EC 3.4.23.5) and neutral proteinase : elastase (EC 3.4.21.11) and cathepsin G were found to be normal in DMC patients. However, alpha 2-macroglobulin in serum was raised. This increase may be associated with a complex formation of alpha 2-macroglobulin with a neutral proteinase released from the cells. Increased levels of chondroitin sulfate N-acetylgalactosamine-6-sulfate sulfatase and sulfamidase and decreased enzymic levels of arylsulfatase A and B (EC 3.1.6.1) were found in leucocytes of DMC patients. The sulfatase activities assayed in the present study support our theory that a specific sulfatase abnormality may exist in the DMC syndrome.

Adenosine Monophosphate↗
PubMed1977

Erythrocyte glutathione perioxidase deficiency in multiple sclerosis.

The present study demonstrates a significant decrease in glutathione peroxidase activity in erythrocytes of 24 patients with multiple sclerosis (MS) when the data are expressed as enzymic units per mg hemoglobin and compared to data from normal controls without known family history of demyclinating diseases. Since selenium is an essential part of glutathione peroxidase, this study also compares the topographic differences in selenium availability (expressed as selenium content of forage) withage) iwth the prevalence and death rates of MS in the USA. The comparison cannot exclude the possibility of a relationship between low selenium content and high prevalence as MS. The data are discussed in relationship to current theories on the pathogenesis of MS.

Adult↗