Search PubMed⌕ Search

Biomedical subjects

K Nielsen

Publications and source records attributed to K Nielsen.

At least 163 records · Page 9Linked to original sources
PubMed1992

Renal vein oxygen saturation in renal artery stenosis.

Renal vein oxygen-saturation was measured in 56 patients with arterial hypertension and unilateral stenosis or occlusion of the renal artery. Oxygen-saturation in blood from the ischaemic kidney (84.4%, range 73-93%) was significantly higher than that from the 'normal' contralateral kidney (81.2%, range 70-90%, P less than 0.001). In only six patients, the ischaemic kidney revealed a venous oxygen-saturation below the contralateral value (mean difference ischaemic-normal kidney 3.2%, range -6 to 15%). The results indicate that the oxygen uptake in the chronic ischaemic kidney is more decreased than its blood flow. This is probably due to decreased filtration fraction and filtered sodium with subsequent reduction in absolute tubular re-absorption of sodium ions.

Adult↗
PubMed1992

Hormonal treatment of cryptorchidism--hCG or GnRH--a multicentre study.

In a modified, double-blind controlled study, 163 prepubertal boys (aged 1.8-13.0 years) with bilateral and 94 (aged 1.5-13.1 years) with unilateral cryptorchidism were allocated to treatment with either human chorionic gonadotrophin (im), gonadotrophin releasing hormone (intranasally) or placebo (intranasally). In individuals with the bilateral condition treatment with human chorionic gonadotrophin resulted in complete descent of both testes in 23% of patients. Treatment with human chorionic gonadotrophin in unilateral cryptorchidism resulted in complete descent in 19% of patients; all results were significantly better than those obtained with gonadotrophin releasing hormone or placebo. Linear and logistic regression analysis of the results obtained by treatment of bilateral disease showed that all treatments were more successful the younger the age of the boys. The data indicated that bilateral and unilateral cryptorchidism respond differently to hormonal treatment. We suggest that human chorionic gonadotrophin should be the first choice of treatment for prepubertal boys older than one year.

Administration, Intranasal↗
PubMed1991

The conformation of porcine-brain natriuretic peptide by two-dimensional NMR spectroscopy.

Two-dimensional (2D) 1H-NMR spectra of porcine-brain natriuretic peptide (pBNP) have been recorded at 300 MHz and 400 MHz. Peak assignments have been made and the combined information from chemical shifts, coupling constants, temperature coefficients and NOEs have been used to determine the conformational properties of pBNP in (C2H3)2SO. Overall the peptide appears to be flexible, with the possibility of some beta-type structure near the C terminus. Some of the assignments and deduced structural features in the current study differ from those in a recent report by Inooka et al. [Inooka, H., Kikuchi, T., Endo, S., Ishibashi, Y., Wakimasu, M. and Mizuta, E. (1990) Eur. J. Biochem. 193, 127-134] which may indicate the sensitivity of the structure of this peptide to differences in solution conditions.

Amino Acid Sequence↗
PubMed1991

Dot immunoperoxidase assay using monoclonal antibody for detection of bluetongue virus antigens.

A rapid, simple dot immunoperoxidase assay (DIPA) is described for visual detection and identification of bluetongue virus (BTV) antigens in samples of infected cell culture fluid. The assay was performed using nitrocellulose (NC) paper and 'dipsticks'. Dots of samples were adsorbed to the NC surface and the remaining non-specific binding sites were blocked with skim milk solution. BTV was detected with either of two murine monoclonal antibodies (4H4, 5G12) to the major group specific antigens of BTV, and the complex was reacted with a peroxidase conjugated anti-mouse immunoglobulin G (heavy- and light-chain specific). Positive reactions were easily visualized as brown spots after enzyme degradation of substrate containing H2O2 and diaminobenzidine (DAB). The DIPA was specific in detecting BTV in samples of cell culture fluid from baby hamster kidney (BHK-21) cells infected with U.S.A. isolates of the five BTV serotypes (2, 10, 11, 13 and 17) known to exist in the U.S.A., and South African isolates of 17 BTV serotypes (1-12, 14-16, 18 and 20), but not with two North American isolates of epizootic hemorrhagic disease of deer virus (EHDV) representing serotypes 1 and 2. Attempts to detect BTV directly in infected sheep blood cells and chick embryo tissue suspensions by DIPA were unsuccessful. Of 55 cell culture fluid samples examined from BHK-21 or Vero cell monolayers inoculated with 55 clinical specimens, propagated initially in embryonating chicken egg (ECE) 11 proved positive and 44 were negative by DIPA. The results were in complete agreement with the conventional ECE and tissue culture isolation systems. The DIPA appears to have potential application, especially as a 'dipstick' kit, for rapid and inexpensive laboratory diagnosis of bluetongue virus infection.

Animals↗
PubMed1991

Treatment of extensive small cell lung cancer with carboplatin and teniposide.

The combination of carboplatin and teniposide has been evaluated in a phase II trial including 47 previously untreated patients with extensive small cell lung cancer. Treatment was given at monthly intervals at a dose of 200 mg/m2 of carboplatin intravenously on day 1 and teniposide at a daily dose of 60 mg/m2 intravenously on days 1-5. Treatment response was complete in 4 (8.9%) and partial in 19 (42.2%) of 45 evaluable patients. The overall response rate was 51.1% (95% confidence interval 36%-66%). The median duration of response was 7.1 months (range 2.1-14.8) and the median survival was 6.7 months (0.3-22.2). Myelosuppression was the most prominent side-effect. Leukopenia (WHO grade 3-4) developed in 17 (37.8%) and thrombocytopenia (grade 3-4) in 5 (11.1%) of 45 patients evaluable for toxicity. 2 treatment-related deaths were registered. The present study shows that the combination of carboplatin and teniposide produces an acceptable response rate, but response duration and survival time are short.

Adult↗
PubMed1991

A murine monoclonal antibody that recognizes a genus-specific epitope in the Salmonella lipopolysaccharide outer core.

A murine monoclonal antibody 105 made from spleen cells of a mouse immunized with a mixture of common Salmonella serotypes reacted specifically with salmonellae from the most frequently encountered O serogroups of A (O:2) to E (O:3), and with strains from the less common O serogroups that represent the subspecies I, II, IIIb, IV, V and VI. Specificity for Salmonella was demonstrated by the lack of reactivity of monoclonal antibody 105 with any of the 30 other different species of Gram-positive and Gram-negative bacteria tested including 16 species in the family of Enterobacteriaceae. Studies to elucidate its binding epitope have shown that it reacts with the three distal sugar residues joined through specific anomeric linkages as present only in the Salmonella lipopolysaccharide outer core, which explains its specificity for the Salmonella. The failure of monoclonal antibody 105 to react with a subspecies IIIa Salmonella suggested a different outer core structure in this strain of Salmonella and also that monoclonal antibodies to the outer core of Salmonella lipopolysaccharide should be useful in the molecular analysis of their diversity.

Animals↗
PubMed1991

Reproducibility of two malignancy grading systems with reportedly prognostic value for oral cancer patients.

Supplementary prognostic factors should be added to the TNM classification for oral squamous cell carcinomas in order to optimize its clinical value. We have recently published two prognostically valuable malignancy grading systems based on histopathology and immunohistology of the most invasive cells in oral squamous cell carcinomas (OSCCs). However, a major problem with classifications based on histologic features is frequent lack of interobserver agreement which limits the clinical value of subjective histologic classifications. Thirty-eight file cases of OSCCs were therefore graded by three pathologists according to criteria of the histologic malignancy grading system which includes 5 morphologic features, each graded from 1 to 4. Agreement was calculated by kappa statistics, which showed that interobserver agreement was not optimal, but significantly better than by chance alone. We also studied the reproducibility of grading of immunohistologic membrane expression of a tumor-associated marker (blood group antigen H), and found a similar level of agreement. We conclude that the clinical value of our grading systems will increase by improving reproducibility.

Carcinoma, Squamous Cell↗
PubMed1991

Grading of nuclear pleomorphism in oral carcinomas. Higher prognostic value than stereological assessment of nuclear volume.

A more objective and reproducible grading system is needed in order to give better prognostic indicators and thereby offer improved treatment to oral cancer patients. Recently, simple objective stereological techniques for cellular estimates have emerged, of which the estimate of mean nuclear volume has shown a correlation with prognosis for various cancers. We have therefore measured the mean nuclear volume in 44 invasive buccal mucosal squamous cell carcinomas and related it to the survival of patients. The mean nuclear volume did not correlate with prognosis for these patients (p = 0.25). However, the nuclear polymorphism, which is subjective even though it is based on well-described criteria in a histopathological grading system, correlated significantly with prognosis (p = 0.03). These findings indicate that the traditional histopathological evaluation of nuclear polymorphism includes valuable prognostic information.

Carcinoma, Squamous Cell↗
PubMed1991

Cleavage of proteins of reproductive secretions by extracellular proteinases of Tritrichomonas foetus.

Cleavage of host defense proteins from reproductive secretions was investigated as a potential virulence mechanism for Tritrichomonas foetus extracellular proteinases. Three categories of susceptibility to digestion were found among the defense proteins tested. Cleavage of fibrinogen, fibronectin, and albumin occurred rapidly with more than 50% of these digested within 30 min. Lactoferrin, immunoglobulin G1, and immunoglobulin G2 were more than 50% digested after 4 h. Transferrin, immunoglobulin M, and immunoglobulin A were the most resistant to the Tritrichomonas foetus extracellular proteinases, since 50% or more of the parent molecule remained after 24 h. The responsible proteinases were classified as cysteine (thiol) proteinases because cleavage was inhibited by the cysteine proteinase specific inhibitor, trans-epoxysuccinyl-L-leucylamido-(4-guanidino)butane and not by the serine proteinase specific inhibitor, phenylmethylsulfonyl fluoride. In addition, alpha 2-macroglobulin, but not alpha 1-antitrypsin, inhibits the action of the proteinases. The ratio of this naturally occurring inhibitor to the quantity of proteinases released may determine whether the above substrates are cleaved in vivo. Since these substrates are implicated in iron acquisition, cell adherence, and acquired immunity, Tritrichomonas foetus proteinases are likely to play a role in host-parasite interactions.

Albumins↗
PubMed1991

Is a skull X-ray necessary after milder head trauma?

During the 2-year period 1985-86 a total of 1,876 patients were admitted to our hospital after milder head trauma including cerebral concussion. Two hundred and eighty four patients who had a skull X-ray were not selected from guidelines. In 1,592 patients without a skull X-ray, signs of an intracranial complication developed in six cases and were verified by CT. In the 284 patients with skull X-ray a fracture was demonstrated in 25, and of these 25 patients only one patient disclosed a cerebral contusion. In the 259 patients with skull X-ray, but without demonstration of fracture, there were subsequently seen one subdural haematoma and one cerebral contusion. The incidence of intracranial complications in patients without and with skull X-ray with or without fracture does not differ significantly. In these circumstances we do not find any justification for routine skull X-ray after milder head trauma.

Brain Concussion↗
PubMed1991

DNA flow cytometry in uterine endometrial carcinoma.

The DNA content was investigated by means of flow cytometry in frozen tumor specimens from 33 patients with uterine endometrial carcinoma. The association was tested between ploidy and S-phase fraction on one hand and clinico-pathological parameters on the other. Aneuploidy appeared in 15 (45%) of the patients, and the average S-phase fraction was 0.18 (0.04-0.34). There was a highly significant correlation between DNA-Index (DI) and histologic differentiation (p = 0.01) and a less significant correlation between DI and estrogen receptor content (p = 0.04). DNA ploidy measured by flow cytometry is a highly reproducible parameter that in addition to routine histopathological examination may provide useful information. Further studies are needed to establish the prognostic importance of the flow cytometric parameters.

Carcinoma↗
PubMed1990

[Insuject-X for children. A clinical trial of the NPH insulin pen].

The use of Insuject-X for NPH insulin was tested by 21 children, age less than or equal to 10 years with insulin dependent diabetes mellitus less than or equal to 1 year, on conventional treatment with NPH insulin once or twice daily. After a preliminary period of one month the syringe injection regimen was changed to injections by Insuject-X for a four-month "pen" period. We observed no significant changes in metabolic control. The mean potency of NPH insulin in partly used cartridges was 103.6 +/- 5.6 IU/ml (range 91.0-118.1, n = 39) with no correlation to the residual volume or days of use. Measurements over 110 IU/ml were seen at the end of the study indicating the need of repeated instruction in use of the pen by children. No microbial contamination of the cartridges, nor any local reactions at injection sites were found. We observed more technical problems than in adult studies indicating that children handle the pen more roughly. The accept of Insuject-X was good as a more convenient means of injecting. All of the children preferred to continue using it.

Adolescent↗