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Biomedical subjects

K A Angquist

Publications and source records attributed to K A Angquist.

At least 19 recordsLinked to original sources
PubMed1999

A new method for continuous tonometric pCO2 measurement--in vitro studies.

The available methods for tonometric pCO2 measurement only provide the possibility of performing intermittent registrations. A new method allowing continuous tonometric pCO2 measurement has been developed and tested in an in vitro model. A standard tonometer for intestinal pCO2 measurement was modified to allow continuous perfusion of the balloon with physiological saline solution in a closed system. The pCO2 in the system was determined in a specially constructed measurement chamber with a TCM20 percutaneous pCO2 monitor. In this in vitro model the tonometer balloon was placed in a saline bath with a constant pCO2 concentration and the measurements from the closed circulating system were compared with those obtained from a standard tonometer placed in the same bath. In 8 and 24 h experiments the circulating system measured the pCO2 value as accurately and reliably as traditional tonometry. This study indicates that the new method makes continuous monitoring of pCO2 possible.

Calibration↗
PubMed1998

Non-invasive assessment of intercompartmental fluid shifts in burn victims.

Two non-invasive methods (the bioimpedance technique, BIA, and the impression method, IM) were studied, to find out whether they are sensitive enough to detect and chronicle the development of the oedema and fluid resuscitation effects (Parkland formula) that occur secondary to a major burn. Ten patients with a total burned body surface area (TBSA) of more than 10% were included in this prospective study. Total body water (TBW), as measured by the resistance (BIA) or F(0) variable (IM), reached a maximum on day 2. The tissue fluid translocation (INT) variable (IM) followed a different course, increasing slowly to reach a maximum on day 6, when it was 40% higher than the 12 h value. TBW and the interstitial translocatable fluid were still increased 1 week post-burn. The non-invasive measurements of TBW (resistance by BIA and F(0) by IM) reflected the anticipated changes in TBW. The phase angle (BIA) indicative of cellular membrane effects of burn and sepsis had its lowest values at day 1.5, and stayed significantly low until day 4. Interestingly, the phase angle was lowest in the two cases that died subsequently. The different time course of the INT value (IM), which reflected the translocatable interstitial fluid volume in skin, may be the result of resuscitation fluid remaining in this compartment, due to the excess sodium content together with a possible change in tissue compliance secondary to the early total water peak on day 2.

Adolescent↗
PubMed1998

Chlamydia pneumoniae in human abdominal aortic aneurysms.

OBJECTIVES: To investigate the presence of Chlamydia pneumoniae DNA in the wall of infrarenal abdominal aortic aneurysms, and in the wall of non-aneurysmal infrarenal abdominal aortas. DESIGN: Case-control study. MATERIALS AND METHODS: The study group consisted of 40 patients operated transperitoneally for an infrarenal abdominal aortic aneurysm (IAAA) (eight females, 32 males; mean age 69 years, median age 68 years). Specimens from the aneurysm wall were taken peroperatively under sterile conditions. The control group consisted of 40 deceased persons without aortic aneurysms (14 females, 26 males; mean age 71 years, median age 70 years). Specimens from the non-aneurysmal infrarenal aortas (NIAA) were collected within 48 h after death. The specimens from both groups were frozen at -70 degrees C immediately after collection. A nested polymerase chain reaction (PCR) method, using two sets of primers designed to detect a fragment of the major outer membrane protein gene of C. pneumoniae, was used. RESULTS: The detection of C. pneumoniae-specific DNA was significantly higher in the study group (14/40 = 35%) than in the control group (2/40 = 5%); (p = 0.001). No clinical factor predicting the presence of C. pneumoniae in the aneurysm wall, could be found. CONCLUSION: Chlamydia pneumoniae was detected at a significantly higher frequency in the wall of IAAAs than in the wall of NIAAs. Although this finding does not prove that C. pneumoniae causes IAAAs, further studies on the possible role of C. pneumoniae in the pathogenesis of aneurysms should be performed.

Aged↗
PubMed1997

Two-dimensional high-resolution electrophoresis of elastin-derived peptides.

Degradation of human aortic elastin in vivo yields a restricted number of differentially sized and charged peptides. Elastin-derived peptides (EDP) can be analyzed by two-dimensional electrophoresis after their extraction from human abdominal aortic tissue by 0.2 M sodium chloride. The peptides were separated according to charge by acetic acid-urea-PAGE and then according to molecular mass by SDS-PAGE. The identity of these peptides as EDP was continued by immunoprecipitation and Western blots. The two-dimensional electrophoretic system can resolve desmosine-like cross-linked EDP of the similar molecular configuration but differing in the number of positively charged amino acid residues. The new separation technique of EDP has the capacity to identify defects in desmosine-like cross-links and may be useful in characterizing abberations in elastin structures.

Animals↗
PubMed1997

Linell classification of breast cancer morphology compared to histologic grading, S-phase fraction and DNA-ploidy.

One hundred and fifty-eight histologically verified mammary carcinomas with known mammographic doubling time (DT) were studied with special emphasis on a morphologic classification proposed by Linell et al. [8, 12, 14, 15]. The hypothesis that Linell classification of ductal carcinomas into comedo, tubuloductal and tubular carcinomas is easy to perform with small inter-observer variations, was not fully confirmed. The Linell classification was found to correlate well with conventional WHO malignancy grading, S-phase fraction and DNA-ploidy. The Linell classification also correlated to surgical stage, lymph node status and DT, but not at all to tumour size. Using distant disease-free survival as an endpoint, the Linell classification gave prognostic information comparable to conventional histologic grading, seeming to be a simple, cheap and reliable method well worth trying on a larger scale.

Adenocarcinoma↗
PubMed1996

Secondary aortoenteric fistulae--changes from 1973 to 1993.

AIM: To investigate a series of patients with secondary aortoenteric fistulas and compare it with a previous series (1985-93 vs. 1973-84). DESIGN: Retrospective study of medical records. SETTING: Sixteen vascular surgical centers in Sweden. PATIENTS: Twenty-seven patients were identified making an overall incidence of 0.5% of all aortoiliac operations. Among aneurysm patients the incidence was significantly lower than in the previous series. One patient record could not be identified. Fourteen primary operations were for aortic aneurysm, 12 for occlusive disease and one was an aortorenal vein bypass. RESULTS: Symptoms of the fistula occurred after a median interval of 90 months which is significantly later than the previous series (32 months; p<0.05). The commonest presentation was bleeding followed by septis. The median diagnostic delay was 10.5 days, which was significantly shorter than in the previous series. Most fistulas involved the duodenum (88%). One patient died before surgery. The postoperative mortality was 28%, significantly lower than in the previous series (58%) (p<0.05). At the end of follow up (median 43 months) significantly more patients were alive than in the previous series (42% vs 18%) (p<0.05). CONCLUSION: Over a 21 year period there seems to have been a decrease in the frequency of secondary aortoenteric fistulas after aneurysm surgery, a longer interval before they occur, a shorter diagnostic delay, and a better survival.

Aorta, Abdominal↗
PubMed1996

Memory dysfunction in mild aphasics.

The effect of mild aphasia (n = 9), as a result of subarachnoid haemorrhage (SAH), was evaluated against one matched (sex, age, and education) control group suffering from SAH of unknown origin without aphasia, and against one matched healthy control group. According to aphasia testing (Reinvang & Engvik, 1980), criteria for a classical diagnosis were not met. Therefore, the patients were characterized as mild aphasics: They generally displayed intact audo-verbal comprehension and repetition abilities, and they demonstrated a fluent, spontaneous speech. However, they showed phonemic and semantic paraphasias, with self-corrections; a few patients displayed alexia and agraphia. Memory performance of these three groups was evaluated by a neuropsychological test battery, designed to tap various components of verbal memory function. From the results it was concluded that: (a) Short-term memory is impaired, as regards the phonological loop and the central executive in working memory, whereas maintenance rehearsal is unaffected, given that the demands on phonological coding is minimized, (b) long-term memory is also generally impaired, whereas long-term learning and forgetting by means of subject-performed tasks proceeds within a normal range. Impairments were hypothesized to reflect less efficient central executive functions of working memory, involving generation of less appropriate semantic codes and phonological representations, (c) mildly aphasic patients are not subjectively aware of their own memory deficits, and (d) aphasia classification by means of standard procedures do not sufficiently characterize the nature of a mildy aphasic patient's memory problems.

Adult↗
PubMed1993

Human postburn oedema measured with the impression method.

The course of tissue swelling in human non-injured skin after burn injury was investigated with a non-invasive impression method that measures force and tissue fluid translocation during mechanical compression of the skin. Time-dependent changes in the fluid translocation and the interstitial-pressure related to impression force were measured on 11 occasions, during 3 weeks, in seven patients postburn. A mathematical model was fitted to the impression force curves and the parameters of the model depicted the time-dependent compartmental fluid shift in the postburn generalized oedema. Tissue fluid translocation increased significantly (P < 0.05) up to a maximum value after 6 days postburn and declined thereafter. This indicated a continuous increase in the generalized postburn oedema for the first 6 days postburn. Impression force at 3 weeks postburn was significantly lower (P < 0.001) as compared with the half-day postburn value, indicating an increased tissue pressure during the first days postburn. Parameter analysis indicated a flux of water-like fluid from the vasculature to the interstitial space during the first 6 days postburn. The spread of the values registered between different measurement sites was, however, large.

Adolescent↗
PubMed1992

Breast carcinoma growth rate described by mammographic doubling time and S-phase fraction. Correlations to clinical and histopathologic factors in a screened population.

BACKGROUND: In a retrospective study, correlations among mammographic doubling times (DT), clinicopathologic prognostic factors, and cytometric predictors were examined. METHODS: One hundred fifty-eight patients with the possibility to calculate mammographic tumor DT were selected and the tumors were histologically reexamined and flow cytometric analysis for ploidy and S-phase fraction (SPF) was performed. RESULTS: The tumors were Stage I in 68%, and 45% were detected by mammographic screening. DT ranged from 0.6 months to an indefinite time (median, 9.0 months). Short DT was significantly correlated to large tumor size (P = 0.01) and advanced pathologic tumor stage (P = 0.016), but there was no correlation between DT and histologic grade. Ploidy analysis indicated that there were 57% aneuploid and 7% tetraploid tumors. There was a significant overrepresentation of euploid tumors among tumors smaller than 10 mm (P = 0.02). Ploidy was correlated to histologic grade (P less than 0.001) and DT (P = 0.009). SPF was calculated in 122 cases. SPF correlated significantly with pathologic stage (P = 0.002), tumor size (P = 0.037), histologic grade (P = 0.001), the presence of axillary lymph node metastases (P = 0.046), DT (P = 0.02), and DNA ploidy (P less than 0.001). Compared with interval carcinoma, screening-detected carcinoma showed favorable characteristics concerning size, stage, DT, ploidy, and SPF but not regarding histologic grade and axillary lymph node metastases. CONCLUSIONS: DT shows great variations. Factors related to tumor biology (i.e., DT, DNA ploidy, and SPF) are strongly correlated with one another, but they have no correlation with axillary lymph node metastases. Cancer detected by screening is discovered at an early stage and shows favorable characteristics concerning DT, ploidy, and SPF.

Adult↗
PubMed1992

Mammographic growth rate, DNA ploidy, and S-phase fraction analysis in breast carcinoma. A prognostic evaluation in a screened population.

BACKGROUND: The authors examined prognostic factors in 158 cases of breast carcinoma with known mammographic tumor volume doubling times (DT). METHODS: The tumors were retrospectively reexamined histologically and flow cytometric analysis of DNA ploidy and S-phase fraction (SPF) was performed on archival paraffin-embedded material in each case. Life tables and Cox multivariate analyses were used for statistical evaluation of prognostic factors. RESULTS: In univariate analysis of survival data, clinical and pathologic stage, histologic grade, the presence of axillary lymph node metastases, and SPF were significant prognostic predictors, but mammographic DT and DNA ploidy were not. SPF also contributed prognostic information in the subgroup of carcinoma cases detected by screening. In a Cox multivariate analysis, SPF, the presence of axillary lymph node metastases, and Stage II-III disease (as opposed to Stage I disease) were independent significant predictors of survival. In univariate analyses of distant disease-free survival, clinical and pathologic stage, tumor size, histologic grade, the presence of involved axillary nodes, DT, and SPF all were significant prognostic factors. CONCLUSIONS: SPF, stage, and lymph node status were important prognostic factors in this patient material with predominantly small and node-negative breast carcinomas, whereas DNA ploidy and mammographic DT provided less prognostic information. The prognosis of carcinoma detected during screening did not differ significantly from that of breast carcinoma discovered otherwise in this selected patient group.

Adult↗
PubMed1992

Self-reported prevalence of disability after subarachnoid haemorrhage, with special emphasis on return to leisure and work.

The prevalences of motor and language impairments and of disabilities in activities of daily living (ADL), leisure and work were investigated in a consecutive series (n = 296) of long-term survivors of subarachnoid haemorrhage (SAH). Motor and language impairments were present in 17 and 20%, respectively. The majority reported independence in self-care (91%) and instrumental (80%) ADL, but among the self-care independent, 23% reported need of personal assistance. Leisure disability occurred in 48% and vocational disability in 40%. Hence, disabilities are more common after SAH than is indicated by occurrences of motor and language impairments. It is concluded that the discrepancy between the prevalences of impairments and of disabilities may be to a great extent caused by coping difficulties in relation to socio-demographic and geographic circumstances. The findings indicate a need for rehabilitative follow-up for virtually all SAH-patients.

Activities of Daily Living↗
PubMed1992

Surgical management of intestinal complications of radiotherapy for gynecological malignancies.

Sixty patients treated for gynecological malignancies with radiation therapy and operated upon because of late intestinal complications of the treatment were studied. Among patients irradiated for cervical carcinoma an incidence of 3.2% of operated intestinal lesions was encountered. Fifty-nine per cent of the women had a history of previous pelvic inflammatory disease on pelvic surgery. The most common symptoms leading to surgery were mechanical subileus/ileus, pain and fistulas. The majority of patients (53%) were operated upon within 2 years after irradiation, but an interval up to 20 years was recorded. 50% were operated upon within 2 years after irradiation, but an interval up to 20 years was recorded. 50% were reoperated during follow-up. Intestinal resections (38%) and by-passes (15%) were the most frequent surgical procedures at first operation. 57% of the patients were operated upon due to acute conditions and 31% were due to chronic problems, 12% due to tumour suspicion. An operation mortality rate of 5% was found. No obvious correlation could be seen between accumulated irradiation dose and severity of complications. The results of surgical intervention and complications are analysed and different strategies in handling these patients discussed.

Adult↗
PubMed1991

Impression technique for the assessment of oedema. Technical improvement and methodological evaluation of a new technique.

A new instrument for the assessment of oedema based on the impression method is described. The measurement parameters are defined and the errors corresponding to the electrical and mechanical stability of the instrument are measured. The overall accuracy is calculated theoretically for the translocated volume. The accuracy and reproducibility are evaluated on plastic foam. The clinical procedure to measure oedema with this instrument is described. We show that the accuracy of the translocated volume parameter is very dependent on the overall stability of the instrument and that this instrument has an overall relative error of less than 7.3 per cent for a representative measurement. Experimental measurements on plastic foam show that the measurement parameters could be reproduced with standard deviations of less than 6 per cent and that the standard deviations for translocated volume are within the calculated overall relative error. Measurements on four patients with chronic oedema in an extremity show significantly different results on locations where pitting could be recognised compared to the contralateral nonoedematous extremity.

Aged↗
PubMed1991

Lp(a) lipoprotein in patients with arterial insufficiency of the lower extremities.

The serum concentration of Lp(a) lipoprotein was determined in 66 patients with peripheral arterial insufficiency of the lower extremities (PAI) and 164 controls. The mean level was higher among the patients than among the controls (236 +/- 248 vs. 129 +/- 159 mg/l, p = 0.01), and values above 300 mg/l were more common among the patients (22/66 vs. 21/164, p less than 0.001). The difference between the 26 female patients and the 94 female controls was statistically significant (280 +/- 268 vs. 118 +/- 141 mg/l, p less than 0.001), but not the difference between the 40 male patients and the 70 male controls (208 +/- 235 vs. 142 +/- 182 mg/l). A high Lp(a) lipoprotein level was not associated with a high LDL-cholesterol level, and there was no significant correlation between the serum levels of Lp(a) lipoprotein and triglycerides++, total cholesterol or HDL-cholesterol. The results indicate, that high Lp(a) lipoprotein levels may be a risk factor for PAI in women.

Adult↗
PubMed1991

Evaluation of the impression technique by measuring interstitial oedema in rat testis.

The impression method for assessment of subcutaneous oedema was evaluated in a rat testis model where the testicular interstitial fluid volume was changed both artificially by infusion of rat plasma and pharmacologically by administration of human chorionic gonadotrophin. Both the integral value and the impression force value, as measured with the impression method, changed with infused volume, and changes as small as 16 microliters (approximately 7% of the total interstitial fluid volume in a testis) could be detected. Rats were treated with a single injection of 100 i.u. human chorionic gonadotrophin in order to induce changes in the volume of interstitial fluid in the testis. Both the integral value and the impression force value seemed to reveal information on testicular interstitial fluid volume in rats treated with human chorionic gonadotrophin that was similar to data revealed by measuring the actual fluid content in the testis. Interstitial fluid volume measured morphometrically in the contralateral testis in human chorionic gonadotrophin-treated rats was significantly correlated to the impression force value (r = 0.75) and the integral value (r = 0.52). This rat testis model proved to be an interesting experimental set-up for evaluation of the impression technique.

Animals↗
PubMed1990

Static and flow cytometric DNA analysis compared to histologic prognostic factors in a cohort of stage T2 breast cancer.

DNA analysis with static and flow cytometry was performed on archival smears and tissue sections in 99 patients with T2 breast cancer (Stage II). Tumour size, histologic grade and axillary node metastases were significant prognostic predictors. Static cytometry revealed 63% aneuploid tumours, and ploidy was significantly correlated to histologic grade and survival. DNA measurements obtained by static and flow cytometry were strongly correlated. According to flow cytometry 53% of the tumours were aneuploid. Flow cytometric DNA analysis correlated to histologic grade and survival and gave prognostic information among the lymph-node negative patients. Ploidy seems to be a significant, although not an independent prognostic indicator for T2 breast cancer.

Adenocarcinoma↗