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Biomedical subjects

T Nilsson

Publications and source records attributed to T Nilsson.

At least 289 records · Page 16Linked to original sources
PubMed1981

Metabolism of estramustine phosphate (Estracyt) in patients with prostatic carcinoma.

Plasma samples from patients with prostatic cancer under oral treatment with estramustine phosphate (Estracyt) were quantitatively analyzed for the presence of the parent drug and some of its possible metabolites. Specific methods based on radioimmunoassay and gas chromatography-mass fragmentography were used. Dephosphorylation and oxidation at the 17-position of estradiol were shown to be the major metabolic routes. The estrone analogue of estramustine was found to be the main metabolite in plasma. Elevated levels of estradiol and estrone showed that hydrolysis of the carbamic ester also occurred in these patients. Their estrogen levels were compared with those of another group of prostatic cancer patients receiving conventional hormonal therapy, polyestradiol phosphate (Estradurin). Similar concentrations of estradiol were found in the two groups but the concentrations of estrone were higher in patients given estramustine phosphate.

Aged↗
PubMed1981

Mechanical properties of Prolene, Ethilion and surgical steel loops.

The present work demonstrates that by using computer calculation on load-deformation curves it is possible to obtain a good deal of useful information on the mechanical properties of material for suturing. The mechanical properties of Prolene, Ethilon and surgical steel loops were investigated. The testing of the loops was performed on a materials testing machine. The load deformation curves were fed into a calculator by a digitizer (Hewlett-Packard 9830 system). A number of examples are given on the practical importance of the different mechanical parameters. Further the investigation showed that the physical characteristics of the materials in Prolene and Ethilon vary with the size of the threads.

Elasticity↗
PubMed1981

The relative importance of Vicryl and Prolene sutures to the strength of healing abdominal wounds.

Based on animal experiments the importance of the sutures for the strength of the healing transversal abdominal wall incision was analyzed. As experimental animals rabbits were used, as suture material Prolene and Vicryl, and the wounds were tested using an Alvetron materials testing machine 3, 6, 10, 15, 28, and 56 days postoperatively. The strength of the wounds with suture intact and suture cut was compared. By measurement of the energy absorption the suture in the transversal incisions have lost their importance between the 15th and the 28th day. The investigation further showed that if Vicryl suture was used instead of Prolene of the same USP size, the sutures did not contribute to the strength of the rectus wounds on the 15th day. The results from the present investigation together with the results from clinical investigations are discussed in relation to the incidence of wound rupture and incisional hernias after use of absorbably suture materials. It is concluded that Vicryl and Dexon sutures of suitable USP size can secure the wound until the time when the suture is superfluous. In the conditions with reduced rate of wound healing, however, it could be risky to apply suture materials which cannot secure the wound after the elapse of 3 weeks.

Abdominal Muscles↗
PubMed1981

Closure of the abdominal wound with single-layer and double-layer technique. Animal studies.

An experimental investigation on rabbits was designed to determine which closure technique, single-layer or double-layer, gave the most secure closure of abdominal wall wounds. Interrupt Prolene sutures size 6-0 were used, and the wounds were tested mechanically in a materials testing machine on the 6th, 15th and 56th day after wounding. The results showed that the double-layer closed wound had, when tested after removal of sutures, a greater strength and higher energy absorption compared to the single-layer closed wound, which however had, when tested with sutures in situ, greater strength and higher energy absorption in the early post-operative phase. The possible explanations of these observations are discussed. Extrapolating from the animal experiments to the clinical situation, it can be concluded, that the double-layer technique was not to be preferred to the single-layer technique when securing a wound against rupture.

Abdominal Muscles↗
PubMed1980

Colonisation of pregnant and puerperal women and neonates with Chlamydia trachomatis.

Chlamydia trachomatis was cultured from cervical specimens of 14 (16.1%) of 231 women applying for legal abortion and from 23 (8.7%) of 273 puerperal women. The chlamydial isolation rate was related to the women's age. Of the pregnant and puerperal women under 20 years C trachomatis was isolated in 10% and 24% respectively; in those aged between 20 and 24 years the rates were 8.7% and 10.2% respectively whereas in those over 24 years the rates were 4.2% in both groups. Chlamydia were isolated more frequently from cervical specimens than from urethral specimens. However, if a cervical specimen alone had been examined the diagnosis would have been missed in three (17%) of 18 women. IgG antichlamydial antibodies (titre greater than or equal to 1/32) were detected by a micro-immunofluorescence test in samples of cord blood from 35 (25%) of 139 infants of the puerperal women. Of the 23 infants born to mothers harbouring chlamydia in the cervix C trachomatis was isolated from the conjuntival folds in five (22.5%). The chlamydial isolation rate from the eyes of the neonates was related to the time of sampling. None of the 108 infants examined between 6 and 7 days old was chlamydia-positive whereas chlamydia could be recovered from the conjunctival folds of four of them when re-examined from three to 23 days later.

Adult↗
PubMed1980

Estracyt--clinical experiences.

Since the introduction of estrogen treatment of prostatic carcinoma in 1941 this treatment has been considered the treatment of choice until recently, when both conventional cytotoxic compounds and hormone cytotoxic agents have been used. Preliminary results are in many aspects very promising (Jönsson, Högberg & Nilsson, 1977). However, controlled randomized series are badly needed to give a final answer how to proceed. So far chemotherapy has been given only for palliation but new approaches and combined treatment modalities might point forward to a treatment that, hopefully, will cure prostatic carcinoma especially if the treatment is started in the very early stages.

Estramustine↗
PubMed1979

N-acetyltransferase phenotype and risk in urinary bladder cancer: approaches in molecular epidemiology. Preliminary results in Sweden and Denmark.

A variable but often significant proportion of urinary bladder cancer in urban areas can be attributed to occupational and cultural (cigarette smoking) situations associated with exposures to various arylamines. The variable N-acetylation of carcinogenic arylamines by human hepatic enzyme systems, the known genetic regulation and polymorphic distribution of this enzyme activity in humans, and the known enhanced susceptibility of individuals with the genetically-distinct "slow acetylator" phenotype to various arylamine toxicities, has prompted examination of possible correlations between N-acetyltransferase phenotype and urinary bladder cancer risk in rural and urban populations. In this context, N-acetylation is viewed as a component of detoxication pathways with respect to arylamine bladder carcinogenesis. In preliminary utilizations of this approach, a population of urban urinary bladder cancer patients from Copenhagen, Denmark displayed a 13% excess (p = 0.065) of individuals with the slow acetylator phenotype (46/71 = 64.8%) when compared to a Danish control population (38/74 = 51.4%). These data are consistent with the possibility that arylamines may play an etiological role in bladder cancer in this locale and that slow acetylator individuals may be at higher relative risk (1.74) than rapid acetylator individuals. As 95% of patients reported histories of smoking, it was not possible to isolate and examine smoking factors. In contrast, a population of rural urinary bladder cancer patients from Lund, Sweden, where bladder cancer incidence (20/100,000) (1971) is lower than in Copenhagen (43.8/100,000) (1968-72), no difference in slow acetylator distribution was observed between bladder cancer (80/115 = 69.6%) and Swedish control (79/118 = 66.9%) populations, indicating a relative lack of involvement of arylamines in the etiology of rural bladder cancer. Populations of "spontaneous" bladder cancer patients would be expected to contain variable portions of disease related to arylamine exposure and would be less likely to display a detectable correlation than would an industrial population with documentable arylamine exposure. Consequently, confirmation of this hypothesis is being pursued by examination of industrial populations in an effort to obtain an empirical estimate of relative risk for slow and rapid acetylator phenotypes. These studies involve exposure-matched workmen both with and without bladder cancer.

Acetyltransferases↗
PubMed1979

Characterization of different regions of the normal human urinary bladder by means of scanning electron microscopy.

A study of the normal human urinary bladder and the proximal urethra was performed using scanning electron microscopy (SEM). Biopsies were evaluated from 27 male patients with benign prostatic hyperplasia, without history or sign of urinary tract malignancy and with cystoscopically normal mucosal finding. The specimens were obtained from the dome, the side-walls and the trigone of the bladder. The characteristic surface architecture of the transitional epithelium was observed in different anatomical regions of the human urinary bladder.

Aged↗
PubMed1979

Surface characteristics of malignant human urinary bladder epithelium studied with scanning electron microscopy.

Biopsies were obtained from 28 male and seven female patients with cystoscopically and histologically confirmed urinary bladder carcionoma. Tissue specimens for light microscopy and scanning electron microscopy (SEM) were obtained from the tumours as well as from cystoscopically tumour-free mucosa of the dome, the lateral walls and the trigone of the urinary bladder and also from the proximal urethra. Certain surface structural changes, which seem to represent malignancy, present in different regions of the urinary bladder were detected by SEM, although not visible by light microscopy.

Aged↗
PubMed1979

Scanning electron microscopy of exfoliated malignant and non-malignant human urothelial cells.

Midstream urine samples were taken from 35 patients with histologically diagnosed urinary bladder carcinoma, from 27 patients without history or sign of malignancy or infection in the urinary tract, and from eight patiens with cystitis. The urine was filtered through Millipore filters, or Nuclepore filters, pore size 5.0 microns, on which the cells were caught. From the same patients biopsies were obtained from different anatomic regions of the urinary bladders as well as from the carcinomas that were present. The filters and the biopsies were examined with scanning electron microscopy (SEM). The exfoliated cells trapped on the filters were in good morphological condition. Idential characteristics of the cell surface morphology were recognized in the biopsies and the exfoliated cells from each patient. In non-malignant cases the cells displayed the regional morphological charcteristics of the urinary bladder. Bacteria and an increased number of red and white blood cells were attached to the cell surface of numerous exfoliated cells in patients with cystitis, but no pleomorphic microvilli were detected in these patients. In cases of malignancy exfoliated cells with pleomorphic microvilli on their surface were detected. A large majority of the exfoliated cells shed in the urine with pleomorphic microvilli on their surfaces still retained enough regional surface characteristics to determine their origin. Some of the cells were completely covered with pleomorphic microvilli and it was impossible to determine their origin.

Biopsy↗
PubMed1979

An indirect method to examine forces affecting Courvoisier's oblique gall-bladder incision.

The aim of this study is to establish a method by which the maximum forces attacking Courvoisier's oblique gall-bladder incision can be evaluated. Nine well-informed patients served as subjects. Four investigations were made: pre-, per-, and two postoperative. The pre- and postoperative maximum isometric muscle strength in pulling forward were measured with a dynamometer. Simultaneously the IEMG was obtained. A muscle tensiometer was used for registration of the peroperative muscle pull of the right abdominal rectus muscle, and IEMG obtained simultaneously. The IEMG makes a calculation of the pre- and postoperative rectus muscle pull possible. The study seems to indicate that the most realistic estimation of the forces attacking the wound in the early postoperative phase is a preoperative measurement of the maximum force in pulling forward (attempted trunk bending). If ruptures in the wound occur during the extubation, ruptures would very likely also occur in the early postoperative phase. Eight weeks after the operation the right rectus muscle has regained its preoperative strength.

Abdominal Muscles↗
PubMed1978

Stimulation of immune reactivity by methoxy-substituted glycerol ethers incorporated into the feed.

In mice, the plaque-forming cell response to sheep red blood cells was stimulated by a mixture of methoxy-substituted glycerol ethers isolated from Greenland shark liver oil and by synthetic 1-0-(2-methoxyhexadecyl)-glycerol, given in the diet. In preliminary experiments, this synthetic compound also increased the ability of parental spleen cells to induce graft-vs.-host reactions in F1 hybrid mice. Glycerol ethers occur in the bone marrow fat of mammals and in the membrane phospholipids. It is postulated that the methoxy-substituted glycerol ethers supplied in the diet may stimulate the bone marrow and/or may be incorporated into membrane lipids, thereby changing the structure and function of the membranes.

Animals↗