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Biomedical subjects

E de Jong

Publications and source records attributed to E de Jong.

At least 37 records · Page 2Linked to original sources
PubMed1992

De-novo biosynthesis of chlorinated aromatics by the white-rot fungus Bjerkandera sp. BOS55. Formation of 3-chloro-anisaldehyde from glucose.

The white-rot fungus Bjerkandera sp. BOS55 produced de-novo several aromatic metabolites. Besides veratryl alcohol and veratraldehyde, compounds which are known to be involved in the ligninolytic system of several other white-rot fungi, other metabolites were formed. These included anisaldehyde, 3-chloro-anisaldehyde and a yet unknown compound containing two chlorine atoms. Additionally GC/MS analysis revealed the production of small amounts of anisyl alcohol and 3-chloro-anisyl alcohol. After 14 days, the extracellular fluid of Bjerkandera BOS55 contained 100 microM veratraldehyde and 50 microM 3-chloro-anisaldehyde. This is the first report of de-novo biosynthesis of simple chlorinated aromatic compounds by a white-rot fungus. Anisaldehyde and 3-chloro-anisaldehyde were also produced by Bjerkandera adusta but not by Phanerochaete chrysosporium.

Basidiomycota↗
PubMed1992

Evidence for a new extracellular peroxidase. Manganese-inhibited peroxidase from the white-rot fungus Bjerkandera sp. BOS 55.

A novel enzyme activity was detected in the extracellular fluid of Bjerkandera sp. BOS 55. The purified enzyme could oxidize several compounds, such as Phenol red, 2,6-dimethoxyphenol (DMP), Poly R-478, ABTS and guaiacol, with H2O2 as an electron acceptor. In contrast, veratryl alcohol was not a substrate. This enzyme also had the capacity to oxidize DMP in the absence of H2O2. With some substrates, a strong inhibition of the peroxidative activity by Mn2+ was observed. Phenol red oxidation was inhibited by 84% with only 1 mM of this metal ion. Because DMP oxidation by this enzyme is only slightly inhibited by Mn2+, this substrate should not be used in assays to detect manganese peroxidase. The enzyme is tentatively named 'Manganese-Inhibited Peroxidase'.

Chromatography, Gel↗
PubMed1992

Biodegradation of polycyclic aromatic hydrocarbons by new isolates of white rot fungi.

Eight rapid Poly R-478 dye-decolorizing isolates from The Netherlands were screened in this study for the biodegradation of polycyclic aromatic hydrocarbons (PAH) supplied at 10 mg liter(-1). Several well-known ligninolytic culture collection strains, Phanerochaete chrysosporium BKM-F-1767, Trametes versicolor Paprican 52, and Bjerkandera adusta CBS 595.78 were tested in parallel. All of the strains significantly removed anthracene, and nine of the strains significantly removed benzo(a)pyrene beyond the limited losses observed in sterile liquid and HgCl2-poisoned fungus controls. One of the new isolates, Bjerkandera sp. strain Bos 55, was the best degrader of both anthracene and benzo(a)pyrene, removing 99.2 and 83.1% of these compounds after 28 days, respectively. Half of the strains, exemplified by strains of the genera Bjerkandera and Phanerochaete, converted anthracene to anthraquinone, which was found to be a dead-end metabolite, in high yields. The extracellular fluids of selected strains were shown to be implicated in this conversion. In contrast, four Trametes strains removed anthracene without significant accumulation of the quinone. The ability of Trametes strains to degrade anthraquinone was confirmed in this study. None of the strains accumulated PAH quinones during benzo(a)pyrene degradation. Biodegradation of PAH by the various strains was highly correlated to the rate by which they decolorized Poly R-478 dye, demonstrating that ligninolytic indicators are useful in screening for promising PAH-degrading white rot fungal strains.

Acetone↗
PubMed1992

Recurrence after breast ablation for ductal carcinoma in situ.

Three patients are described having locally recurrent invasive breast cancer after breast ablation for ductal carcinoma in situ (DCIS). All had initially extensive type ductal carcinoma in situ without evidence of invasion in adequately sampled microscopical studies. One patient developed a scar recurrence and lung metastases 2 years after surgery; one patient showed a scar recurrence 3 years after operation and one patient had a recurrence in the chest wall 27 years after surgery. Although generally stated that ablative therapy offers a 100% cure in case of DCIS, these cases illustrate that local recurrence may occur. Possible causes and preventions are discussed.

Aged↗
PubMed1991

Subjective ordering and working memory in alcoholic Korsakoff patients.

Frontal-lobe dysfunction of alcoholic Korsakoff patients was studied by presenting four tasks requiring short-term retention, as well as different degrees and types of control. Digit span forward was considered a measure of passive short-term retention; missing scan measures memory search and comparison, in addition to retention; and two subjective ordering tasks measure active generation of responses in addition to the processes in the other two tasks. The results showed no evidence of reduced performance for any of these tasks, when compared with performance of control subjects. The hypothesis that Korsakoff patients have a frontal-lobe dysfunction in addition to their amnesia needs some qualification because of these results: Frontal-lobe function specific to the ordering of verbal responses seems to be intact in Korsakoff patients.

Adult↗
PubMed1991

Inflammatory linear verrucous epidermal naevus (ILVEN) versus linear psoriasis. A clinical, histological and immunohistochemical study.

Inflammatory Linear Verrucous Epidermal Nevus (ILVEN) has been suggested to be a separate disease entity. However, the distinction from linear psoriasis has been discussed in the literature over recent decades. The aim of the present study was to investigate, in addition to the clinical and histological criteria, the immunohistochemical aspects of inflammation, epidermal proliferation and keratinization. From a clinical and histological point of view, ILVEN and psoriasis, according to the established criteria, have been proved to overlap. The immunohistochemical study suggests that the following procedures have an additional diagnostic impact: assessment of elastase-positive cells, assessment of keratin 16 and of keratin 10.

Adult↗
PubMed1990

Statistical analysis of gamma-emitting radionuclide concentrations for three fields in southern Saskatchewan, Canada.

During 1988, the spatial variability of the natural gamma-emitting radionuclides (238U, 232Th, and 40K) and the artificial radionuclide 137Cs were studied in three near-level unfertilized fields in Saskatchewan, Canada. One field was used as a native (uneroded) control site; the other two sites have been cultivated, one since 1979 and the other since at least the 1940s. The two cultivated sites have been eroded by aeolian processes and tillage practices. Autocorrelation analysis indicated that most of the radionuclides were not serially correlated for the two depth increments sampled (0-15 cm and 15-30 cm). Autocorrelation is a necessary procedure when equally spaced transect sampling is employed, since sample independence cannot be assumed. Robust and nonrobust statistical summaries are presented for the selected gamma-emitting radionuclide concentrations. Robust statistical estimates of location and dispersion are favored when distributions are not normal or when the distribution is skewed. Median concentrations for the three fields indicated that 238U, 232Th, 40K, and 137Cs were similar to areas in the U.S. and to other areas in southern Saskatchewan. Median 238U activity concentrations were between 31.4 and 34.1 Bq kg-1; 232Th concentrations were between 29.6 and 31.2 Bq kg-1; 40K concentrations were between 471 and 502 Bq kg-1; and 137Cs concentrations were between 10.0 and 12.6 Bq kg-1. The variability of natural radionuclides in a given field for a specific depth increment was generally low, with coefficients of variation less than or equal to 10%. The variability of 137Cs concentrations was greater, ranging from 18% to 23%. Nonparametric tests indicated a significant decrease in 214Bi concentration (238U indicator corrected for 222Rn) with depth of the 1979 field, and an increase in 228 Ac (232Th) with depth in the 1940s field. Significant differences in concentration between fields were indicated for all radionuclides except for 228 Ac. The possible reasons for differences in depth and between fields are briefly discussed.

Cesium Radioisotopes↗
PubMed1990

Markers for proliferation and keratinization in the margin of the active psoriatic lesion.

To study the development of the psoriatic lesion, biopsies were taken from the margin of spreading plaques and acute pinpoint papules. Consecutive sections across the margin were stained using different monoclonal antibodies to characterize epidermal growth (Ki-67) and abnormal keratinization (Ks8.12, RKSE60). All three immunohistochemical markers showed pronounced changes in the lesional skin with a clear transition to the uninvolved skin. The suprabasal Ks8.12 binding was the earliest change found in the epidermis, and its localization high in the suprabasal compartment indicates that metabolic dysregulation in this cell population was not a consequence of the recruitment process in the basal layer.

Adult↗
PubMed1989

The expression of heat shock protein hsp27 and a complexed 22-kilodalton protein is inversely correlated with oncogenicity of adenovirus-transformed cells.

We isolated a monoclonal antibody that immunoprecipitated two proteins of 22 and 27 kilodaltons (kDa) from nononcogenic adenovirus type 5 early region 1 (E1)-transformed rat cells but not from oncogenic adenovirus type 12 E1-transformed rat cells. In a variety of adenovirus-transformed cells including cells transformed by E1A and the c-H-ras oncogene, we found a perfect, inverse correlation between the presence of these two proteins and the oncogenicity of these cells in syngeneic immunocompetent rats. Characterization of the two proteins revealed that they occur in a large (700-kDa) complex and that the 27-kDa protein is identical to the already known 27-kDa (28-kDa) heat shock protein hsp27. The suppression of the hsp27 protein in oncogenic cells is further demonstrated by the fact that its mRNA is absent even after heat-shock induction.

Adenoviruses, Human↗
PubMed1989

Disturbed fibrinolysis in patients with inflammatory bowel disease. A study in blood plasma, colon mucosa, and faeces.

Using specific assays, we studied fibrinolytic activity in plasma and colonic mucosa biopsies of 28 patients with inflammatory bowel disease (IBD) (12 with Crohn's disease, 16 with ulcerative colitis) and 28 control patients without inflammatory bowel disease or colon malignancy. Blood coagulation was studied using standard techniques. In plasma of IBD patients significantly decreased tissue type plasminogen activator activity (t-PA) (p less than 0.02), increased plasminogen activator inhibition (PAI) (p less than 0.01) and fibrinogen (p less than 0.001), and prolonged thrombin time (p less than 0.001) and prothrombintime (p less than 0.001) were found. In colon mucosa the percentage of t-PA to urokinase type plasminogen activator (u-PA) was 80:20% in the control group and 71:29% in the IBD group in non-inflamed mucosa. In inflamed mucosa the plasminogen activator percentage was 55:45%, significantly different (p less than 0.01) from the control group. There was also a significant absolute increase in u-PA activity and decrease of t-PA activity in the inflamed mucosa compared to the control group (p less than 0.001 and p less than 0.01, respectively). Patients with inflammatory bowel disease therefore have significant changes in components of the fibrinolytic and coagulation system both systemically and locally in colon mucosa. These changes might contribute to an increased risk for thromboembolic complications and possibly to the pathogenesis of the colitis and to the local complications such as bleeding.

Adult↗
PubMed1987

Antithrombin III: biodistribution in healthy volunteers.

Five healthy volunteers were injected intravenously with 73-90 uCi purified human 131I-Antithrombin III (AT III), specific biological activity 5.6 U/mg. The tracer data were analysed using a three compartment model. The plasma radioactivity half life was 66.2 +/- 1.2 (sem) h, the fractional catabolic rate constant of the plasma pool was 0.025 +/- 0.002 (sem) h-1. These data were comparable with those described in the literature. Because of the difficulty in translating the mathematical analysis of various compartments into the biological model, biodistribution was monitored by a gamma camera linked to a DEC PDP 11/34 computer system. Dynamic and static images were obtained at fixed time intervals following the injection of 131I-AT III. Whole body scanning at intervals between the time of injection (t = 0) and t = 24.5 h showed 131I-AT III distribution over the heart, lungs, liver, spleen and great vessels. Dynamic scanning was performed over the heart, spleen and liver. Overlayed frames in the first ten minutes after the 131I-AT III injection showed the following radioactivity expressed as percentage of the injected dose; 5.9% +/- 0.3 (sem) over the heart, 10.6% +/- 0.9 (sem) over the liver and 1.1% +/- 0.1 (sem) over the spleen. A slower decline of the radioactivity between t = 0 and t = 24 h; (19%) was measured over the liver compared with the radioactivity disappearance over the heart region. This shows, in combination with the fact that the radioactivity disappearance over the heart was identical with the radioactivity decline measured in the plasma samples that retention of 131I-AT III occurred in the liver.(ABSTRACT TRUNCATED AT 250 WORDS)

Antithrombin III↗
PubMed1987

Increased plasminogen activator inhibition levels in malignancy.

Plasminogen activator(PA)-tissue and urokinase type-and PA-inhibition in plasma were investigated in 52 consecutive cancer patients with a variety of tumors. At first patients were analyzed as one group. Secondly patients were subdivided into two groups, one with (n = 42) and one without (n = 10) metastasis. Our results show that tissue-type-PA antigen (t-PA-antigen) and PA-inhibition were both significantly increased irrespective of the presence or absence of tumor metastasis (p less than 0.001 compared to age matched healthy controls. In the group without metastasis a significantly decreased level of t-PA activity was found (p less than 0.001) but in the group with metastasis t-PA activity was normal. These data seem to reject the hypothesis that decreased plasma fibrinolytic activity is one of the prerequisites for tumor metastasis.

Antigens↗
PubMed1987

Monitoring heparin and haemostasis during reconstruction of the abdominal aorta.

In spite of its unpredictable kinetics, heparin is still not generally monitored during peripheral vascular surgery. To evaluate heparin levels and neutralisation, plasma heparin concentrations were measured using a chromogenic substate method during 20 consecutive operations on the Abdominal Aorta. This was combined with measuring activated partial thromboplastin time (APTT), thrombin time (ThT), prothrombin time (PT), antithrombin-III (AT-III) and fibrinogen concentration. Heparin concentration 5 min after administration and the elimination rate showed a wide variation. Using a standard dosage for all patients resulted in plasma heparin levels that are potentially too low in some patients. The APTT and ThT were found to be unsuitable for an exact calculation of heparin levels. Protamine administration based on the surgeon's judgement of haemostasis was inadequate. Furthermore an intraoperative decrease of AT-III and fibrinogen was seen in eight patients. It is advisable and possible to have direct monitoring of heparin concentration during peripheral vascular surgery.

Aorta, Abdominal↗
PubMed1986

Purified radiolabeled antithrombin III metabolism in three families with hereditary AT III deficiency: application of a three-compartment model.

Purified human radioiodinated antithrombin III (125I-AT III) was used to study its metabolism in six members from three different families with a known hereditary AT III deficiency. Six healthy volunteers served as a control group. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and crossed immunoelectrophoresis (CIE) showed the purified AT III to be homogeneous. Amino acid analysis of the protein revealed a composition identical to a highly purified internal standard. The specific activity was 5.6 U/mg. Analysis of plasma radioactivity data was performed, using a three-compartment model. Neither plasma disappearance half-times nor fractional catabolic rate constants differed significantly between patients and control subjects. The mean absolute catabolic rate in the patient group was significantly lower than that of the control group at 2.57 +/- 0.44 and 4.46 +/- 0.80 mg/kg/day, respectively. In addition, the mean patient alpha 1-phase, flux ratio (k1,2 and k2,1) of the second compartment alpha 2-phase and influx (k3,1) of the third compartment were significantly reduced as compared with control values. It has been tentatively concluded that the observed reduction in the second compartment may be caused by a decrease in endothelial cell surface binding.

Adult↗
PubMed1985

alpha 2-Plasmin inhibitor metabolism in patients with liver cirrhosis.

We describe the metabolism of purified human alpha 2-plasmin inhibitor in patients with liver cirrhosis to determine whether low plasma concentrations of alpha 2-plasmin inhibitor are the result of impaired synthesis or increased catabolism or both. A kinetic study was performed with 131I-alpha 2-plasmin inhibitor as a sensitive parameter of fibrinolysis in 14 patients with histologically proved liver cirrhosis compared with six healthy control subjects. Eight patients had macronodular cirrhosis (with positive hepatitis B surface antigen), and six had micronodular cirrhosis as a result of alcohol abuse. None of the patients had clinical signs of ascites, and in all the disease was stabilized. alpha 2-Plasmin inhibitor levels biologically and immunologically measured were decreased in all patients. Ten microCi 131I-alpha 2PI was injected intravenously, the disappearance of plasma radioactivity was measured, and turnover data were calculated according to the function x(t) = A1e-alpha 1t + A2e-alpha 2t + Be-beta t. Mean (+/- SD) turnover data in the control subjects were plasma radioactivity half-life 60.1 +/- 5.3 hours, fractional catabolic rate constant of the plasma pool 0.0318 +/- 0.0106 hr-1, and absolute catabolic (synthetic) rate constant 2.10 +/- 0.60 mg/kg/day. The alpha 1-phase was 1.26 +/- 0.23, and the transcapillary influx constant (k2,1) was 0.974 +/- 0.109 hr-1. In the patients, plasma radioactivity half-life was 58.7 +/- 12.09 hr, and fractional catabolic rate constant of the plasma pool 0.0283 +/- 0.0043 hr-1. The alpha 1-phase 4.74 +/- 6.48 and the transcapillary influx (k2,1) 3.08 +/- 3.9 hr-1 were both significantly increased compared with control values (p less than 0.05 and p less than 0.05, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1980

The fibrous tissue architecture of the female perineal region.

In relation to the question which type of episiotomy should be preferred, the subcutaneous layer of the anatomical perineum of three adult female subjects was bluntly dissected. In the urogenital triangle constantly five fibrous septa were observed, and in the posterior (anal) triangle several antero-posterior septa as well as septa radiating from the walls of the anal canal and the vagina. In addition, dense connective tissue structures overly the ischial tuberosity. Microscopical studies showed that all septa contain blood vessels and bundles of smooth muscle fibres. Only the dorsal, median septum which connects the anal canal to the coccyx, contains bundles of striated muscle fibres, too. The results show that only the median episiotomy leaves the system of subcutaneous perineal fibrous tissue septa unimpaired.

Adipose Tissue↗