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E Nilsson

Publications and source records attributed to E Nilsson.

At least 37 records · Page 2Linked to original sources
PubMed2001

A functional prothrombin gene product is synthesized by human kidney cells.

gamma-carboxylated polypeptides were detected in the human kidney by immunohistochemistry with a monoclonal antibody (M3B) specific for gamma-carboxyglutamyl residues. An approximately 70-kDa gamma-carboxylated protein, subsequently identified as prothrombin, was isolated from the intracellular compartment of cultured human embryonic kidney (HEK293) cells by immunoaffinity chromatography on M3B-coupled resin. Immunohistochemical analyses demonstrated that prothrombin and another vitamin K-dependent protein, the growth arrest-specific protein 6, were detectable in human kidney. As in the liver, the kidney synthesizes prothrombin as a zymogen that can be cleaved by ecarin to an amidolytically active serine protease that is inhibited by hirudin. This demonstrates for the first time the de novo synthesis of a full-length, gamma-carboxylated, and functional prothrombin gene product by human kidney cells.

Antibodies, Monoclonal↗
PubMed2001

Operative findings in recurrent hernia after a Lichtenstein procedure.

BACKGROUND: Recurrence after inguinal herniorraphy continues to be a problem, although the Lichtenstein technique (anterior, open fixated sheet mesh) is associated with reduced recurrence rates. Recurrence after Lichtenstein repair is suspected to be caused by insufficient fixation and overlap at the pubic tubercle. METHODS: A review was made of 87 records from operations for recurrence after a previous Lichtenstein procedure, based upon national and large area data bases, recording 95% (Denmark) and 50% (Sweden) of all inguinal hernia operations. RESULTS: Direct recurrences were found in 62%, whereas the remaining recurrences were either indirect (17%), femoral (13%), or other/unclassified (8%). CONCLUSION: The most plausible explanation for the development of the direct recurrences is an insufficient medial mesh fixation and overlap over the pubic tubercle. Avoidance of more than half of the recurrences after the Lichtenstein repair may be obtained by increased attention to this specific technical aspect of the operation.

Hernia, Inguinal↗
PubMed2001

Mathematical modelling of physicochemical reactions and transport processes occurring around a platinum cathode during the electrochemical treatment of tumours.

The electrochemical treatment (EChT) of tumours is an anti-tumour therapy in which a continuous direct current is applied to electrodes, placed in or near a tumour. Promising results have been reported from clinical trials in China, where more than 10,000 patients have been treated with EChT during the past 10 years. Before clinical trials can be conducted outside of China, a reliable dose-planning strategy has to be developed. One approach in achieving this is the use of physicochemical simulation models. A simplified mathematical model of the physicochemical processes, occurring around a spherical platinum cathode during EChT, is developed and visualized in three steps in this paper. In the final step, tissue is treated as an aqueous solution of sodium chloride, containing a bicarbonate buffer system and organic constituents susceptible to reactions with hydroxyl ions. This model is shown to give a good description of the pH profile obtained around the cathode after EChT. The simulation results reveal a strong correlation between the pH profiles and size of experimentally measured lesions, thus indicating that it is the spreading of hydroxyl ions that determines the extent of tissue destruction around the cathode. In addition, the simulations indicate that the model could be of use in predicting the size of a lesion produced by EChT.

Animals↗
PubMed2001

Expression and action of transforming growth factor beta (TGFbeta1, TGFbeta2, TGFbeta3) in normal bovine ovarian surface epithelium and implications for human ovarian cancer.

The majority of ovarian tumors are derived from the single layer of epithelial cells on the surface of the ovary termed the ovarian surface epithelium (OSE). Stromal cell-OSE interactions are postulated to be an important aspect of normal OSE biology and the biology of ovarian cancer. Transforming growth factor beta (TGFbeta) has been shown to often be a mesenchymal cell-derived growth factor that mediates stromal cell-epithelial cell interactions in a variety of different tissues. The current study investigates the expression and action of TGFbeta isoforms (TGFbeta1, TGFbeta2, and TGFbeta3) in OSE and the underlying stroma in both normal bovine and human tumor tissues. Normal bovine ovaries are similar to human ovaries and are used as a model system to investigate normal OSE and stromal cell functions. All three TGFbeta isoforms and their receptor, transforming growth factor beta receptor type II (TGFbetaRII), proteins were found to be detected in the OSE from normal bovine ovaries using immunohistochemistry. Ovarian stromal tissue also contained positive immunostaining for TGFbeta isoforms and TGFbetaRII. RNA was collected from normal bovine OSE and ovarian stromal cells to examine TGFbeta gene expression. TGFbeta1, TGFbeta2, and TGFbeta3 transcripts were detected in both freshly isolated and cultured bovine OSE and stromal cells by a sensitive quantitative polymerase chain reaction assay. TGFbeta1 and TGFbeta2 mRNA levels were found to be present at similar levels in freshly isolated OSE and stroma. Interestingly, TGFbeta3 mRNA levels were significantly higher in freshly isolated OSE than stromal cells. All but TGFbeta3 mRNA in OSE increased when the cells were cultured. Observations indicate that normal bovine OSE and stroma cells express the three TGFbeta isoforms in vivo and in vitro. Human ovarian tumors from stage II, stage III and stage IV cases were found to express TGFbeta1, TGFbeta2, TGFbeta3 and TGFbetaRII protein primarily in the epithelial cell component by immunohistochemistry analysis. The stromal cell component of the human ovarian tumors contained little or no TGFbeta or TGFbetaRII immunostaining. TGFbeta actions on bovine OSE and stromal cells were also investigated. TGFbeta was found to inhibit the growth of OSE, but not stromal cells. To further examine the actions of TGFbeta on OSE, the expression of two growth factors previously shown to be expressed by OSE were analyzed. TGFbeta1 was found to stimulate the expression of both keratinocyte growth factor (KGF) and kit ligand/stem cell factor (KL) by bovine OSE. Therefore, TGFbeta actions on OSE will likely promote a cascade of cell-cell interactions and cellular responses involving multiple growth factors. The effects of regulatory agents on TGFbeta expression by the bovine OSE were examined. Transforming growth factor alpha (TGFalpha) stimulated TGFbeta1 expression, TGFbeta1 stimulated TGFbeta2 expression, and follicle stimulating hormone (FSH) stimulated TGFbeta3 expression. These results demonstrate that TGFbeta isoforms are regulated differently by the regulatory agents tested. In summary, all the TGFbeta isoforms are differentially expressed by the OSE and TGFbeta appears to have an important role in regulating OSE and possibly stromal-OSE interactions. A complex network of endocrine and paracrine interactions appears to influence the expression and actions of TGFbeta on OSE. Abnormal expression and/or action of TGFbeta is postulated to in part be involved in the onset and progression of ovarian cancer.

Animals↗
PubMed2001

Carrageenan-induced subacromial bursitis caused changes in the rat's rotator cuff.

This study was designed to investigate the histologic expression of the rat's supra- and infraspinatus tendons in carrageenan-induced subacromial bursitis. Thirty-two rats received subacromial injections with carrageenan (n = 28) or saline (n = 4). The tendons were analysed microscopically after staining with hematoxyline eosin, Van Giesons hematoxyline and immunofluorescent staining of fibronectin and fibrinogen. In the controls (saline x 10) and group A (carrageenan x 5) there were no changes in the tendons. In group B (carrageenan x 10) 3/8 rats showed macrophages between the collagen fibres and an increased staining of fibronectin. In group C (double dosis carrageenan) all rats had signs of fibrocartilaginous metaplasia in the supraspinatus tendon. In eight of these specimens even bony metaplasia was seen. The infraspinatus tendon showed fibrosis but no fibrocartilaginous metaplasia. The results showed that iatrogenic bursitis after carrageenan subacromial injections was associated with marked changes of the supraspinatus tendon.

Acromion↗
PubMed2001

Electrochemical treatment (EChT) effects in rat mammary and liver tissue. In vivo optimizing of a dose-planning model for EChT of tumours.

BACKGROUND: A reinvented technique for tumour therapy, electrochemical treatment (EChT), is attracting increasing attention. This study compared results from treatment of liver and mammary tissue focusing on destruction and pH changes in the tissue close to the treatment electrodes. Subsequently, data were compared with a dose-planning model. METHODS: Mammary or liver tissue in 50 adult female Sprague Dawley rats was given EChT with a constant, direct current. The electrodes used were Pt/Ir (9:1) with spherical tips. In situ pH measurements were taken with a micro-combination glass electrode. RESULTS: Spherical lesions were produced in both liver and mammary tissue. No significant difference was detected when comparing the size of the lesions in the two kinds of tissue. Similar pH profiles were obtained in tissue surrounding the electrodes, with pH values changing rapidly from unphysiological to neutral status within the space of a few millimetres. The pH at the border of the macroscopic destruction zone, regardless of tissue type or coulomb dosage, correlated well with specific values (4.5-5.5 at the anode and between 9 and 10 at the cathode). CONCLUSION: The analogous destruction patterns in mammary and liver tissue support the hypothesis that EChT has similar results in at least these two different types of tissue. This implies that the destructive pattern caused by the treatment may be the same also in tumours.

Animals↗
PubMed2001

Chronic post-sternotomy pain.

BACKGROUND: Chronic postoperative pain is a well-recognised problem. The incidence of severe incapacitating pain is about 3-5% after various types of surgery such as thoracotomy, repair of inguinal hernias and mastectomy. Sternotomy causes considerable postoperative pain and patients with chronic post-sternotomy pain are often referred to pain clinics. Epidemiological studies on chronic post-sternotomy pain are scarce, however. The aim of this paper was to study the incidence and possible risk factors of chronic pain following sternotomy operations performed for coronary bypass grafting or thymectomy. METHODS: Two groups of patients were studied for persistent pain following sternotomy operations. A questionnaire was sent in January 1997 to 71 patients with myasthenia gravis (MG) who had undergone a thymectomy during 1985-1996 and 720 patients who had had coronary bypass grafting (CABG) in 1994 were interviewed by letter. The patients were asked about the presence of pain and other symptoms in the chest, shoulders, arms or legs that they thought were connected to surgery. They were also asked about the quality of the pain and its evolvement with time. The patients' records were checked for details about surgery, anaesthesia and the state of the coronary disease. RESULTS: The response rate was 87%. The interval between the interview and surgery varied from 6 months to 12 years in the MG group and it was 2-3 years in the CABG group. In the MG group, 27% of the patients reported chronic post-sternotomy pain, which was moderate to severe in 48% of the patients. In the CABG group, 28% of the patients still had post-sternotomy pain, which was moderate to severe in 38% of patients. Of the patients who had post-sternotomy pain, one-third reported sleep disturbances due to the pain. CONCLUSION: Chronic post-sternotomy pain is an important complication that may have a significant impact on the patient's everyday life. Future studies will show whether minimising complications, improving postoperative care and starting early adequate pain management will reduce the incidence of this problem.

Adolescent↗
PubMed2001

Lentiviral-mediated gene transfer into haematopoietic stem cells.

OBJECTIVES: Lentiviral vectors can transduce nondividing cells. As most haematopoietic stem cells (HSCs) are nondividing in vivo, lentiviral vectors are promising viral vectors to transfer genes into HSCs. DESIGN AND SETTING: We have used HIV-1 based lentiviral vectors containing the green fluorescent protein (GFP) gene to transduce umbilical cord blood CD34+ and CD34+/CD38- cells prior to transplantation into NOD/SCID mice. RESULTS: High level engraftment of human cells was obtained and transgene expression was seen in both myeloid and lymphoid lineages. Bone marrow from the primary transplant recipients mice was transplanted into secondary recipients. GFP expression was seen in both lymphoid and myeloid cells in the secondary recipients 6 weeks posttransplantation. Human haematopoietic progenitor colonies were grown from both primary and secondary recipients. Over 50% of the haematopoietic colonies in these recipients were positive for the GFP transgene by PCR. Following inverse PCR, amplified fragments were sequenced and integration of the vector into human genomic DNA was demonstrated. Several vectors containing different internal promoters were tested in NOD/SCID mice that had been transplanted with transduced CD34+ and CD34+/CD38- cells. The elongation factor-1alpha (EF-1alpha) promoter gave the highest level of expression, both in the myeloid and lymphoid progeny of the engrafting cells. CONCLUSIONS: These data collectively indicate that candidate human HSCs can be efficiently transduced with lentiviral vectors and that the transgene is highly expressed in their progeny cells.

Animals↗
PubMed2001

Reoperation after recurrent groin hernia repair.

OBJECTIVE: To analyze reoperation rates for recurrent and primary groin hernia repair documented in the Swedish Hernia Register from 1996 to 1998, and to study variables associated with increased or decreased relative risks for reoperation after recurrent hernia. METHODS: Data were retrieved for all groin hernia repairs prospectively recorded in the Swedish Hernia register from 1996 to 1998. Actuarial analysis adjusted for patients' death was used for calculating the cumulative incidence of reoperation. Relative risk for reoperation was estimated using the Cox proportional hazards model. RESULTS: From 1996 to 1998, 17,985 groin hernia operations were recorded in the Swedish Hernia Register, 15% for recurrent hernia and 85% for primary hernia. At 24 months the risk for having had a reoperation was 4.6% after recurrent hernia repair and 1.7% after primary hernia repair. The relative risk for reoperation was significantly lower for laparoscopic methods and for anterior tension-free repair than for other techniques. Postoperative complications and direct hernia were associated with an increased relative risk for reoperation. Day-case surgery and local infiltration anesthesia were used less frequently for recurrent hernia than for primary hernia. CONCLUSIONS: Recurrent groin hernia still constitutes a significant quantitative problem for the surgical community. This study supports the use of mesh by laparoscopy or anterior tension-free repair for recurrent hernia operations.

Hernia, Inguinal↗
PubMed2001

Laparoscopic cholecystectomy versus mini-laparotomy cholecystectomy: a prospective, randomized, single-blind study.

OBJECTIVE: To analyze outcomes after open small-incision surgery (minilaparotomy) and laparoscopic surgery for gallstone disease in general surgical practice. METHODS: This study was a randomized, single-blind, multicenter trial comparing laparoscopic cholecystectomy (LC) to minilaparotomy cholecystectomy (MC). Both elective and acute patients were eligible for inclusion. All surgeons normally performing cholecystectomy, both trainees under supervision and consultants, operated on randomized patients. LC was a routine procedure at participating hospitals, whereas MC was introduced after a short training period. All nonrandomized cholecystectomies at participating units during the study period were also recorded to analyze the external validity of trial results. The randomization period was from March 1, 1997, to April 30, 1999. RESULTS: Of 1,705 cholecystectomies performed at participating units during the randomization period, 724 entered the trial and 362 patients were randomized to each of the procedures. The groups were well matched for age and sex, but there were fewer acute operations in the LC group than the MC group. In the LC group 264 and in the MC group 150 operations were performed by surgeons who had done more than 25 operations of that type. Median operating times were 100 and 85 minutes for LC and MC, respectively. Median hospital stay was 2 days in each group, but in a nonparametric test it was significantly shorter after LC. Median sick leave and time for return to normal recreational activities were shorter after LC than MC. Intraoperative complications were less frequent in the MC group, but there was no difference in the postoperative complication rate between the groups. There was one serious bile duct injury in each group, but no deaths. CONCLUSIONS: Operating time was longer and convalescence was smoother for LC compared with MC. Further analyses of LC versus MC are necessary regarding surgical training, surgical outcome, and health economy.

Bile Ducts↗
PubMed2000

Generalized potential of adult neural stem cells.

The differentiation potential of stem cells in tissues of the adult has been thought to be limited to cell lineages present in the organ from which they were derived, but there is evidence that some stem cells may have a broader differentiation repertoire. We show here that neural stem cells from the adult mouse brain can contribute to the formation of chimeric chick and mouse embryos and give rise to cells of all germ layers. This demonstrates that an adult neural stem cell has a very broad developmental capacity and may potentially be used to generate a variety of cell types for transplantation in different diseases.

Animals↗
PubMed2000

Electrochemical treatment of tumours.

The electrochemical treatment (EChT) of tumours implies that tumour tissue is treated with a continuous direct current through two or more electrodes placed in or near the tumour. The treatment offers considerable promise of a safe, simple and relatively noninvasive anti-tumour therapy for treatment of localised malignant as well as benign tumours. Although more than 10,000 patients have been treated in China during the past 10 years, EChT has not yet been universally accepted. The reason for this is the lack of essential preclinical studies and controlled clinical trials. Uncertainties regarding the destruction mechanism of EChT also hinder the development of an optimised and reliable dose-planning methodology. This article reviews the collected Chinese and occidental experiences of the electrochemical treatment of tumours, alone and in combination with other therapies. The current knowledge of the destruction mechanism underlying EChT is presented along with different approaches towards a dose planning methodology. In addition, we discuss our view of different important parameters that have to be accounted for, if clinical trials are to be initiated outside of China.

Animals↗
PubMed2000

Cholecystectomy in Sweden 1989 and 1994: long admissions assessed by the inpatient registry.

The purpose of this study was to compare cholecystectomy in Sweden (pop. 8.9 million) 1989 to 1994 when the diffusion of laparoscopic cholecystectomy (LC) was completed, focusing on long hospital admissions as a proxy indicator of adverse events. This was an observational study of all patients operated on with cholecystectomy in 1989 and 1994 (n = 19,432) from the National Inpatient Registry. The risk of a long admission was analyzed by multivariate analyses. Odds ratios of long admissions were computed considering gender, age groups, acute or chronic gallstone disease, 1989 and 1994, county level of operations per 1000 inhabitants, and hospital categories. Stratified analyses were performed by acuteness of disease, and year. Long admissions were defined as lasting longer than 20 days in 1989 and 14 days in 1994. Odds ratios of a long admission increased steeply with age and acute gallstone disease. The county level of operations per 1000 inhabitants had no influence on risk nor did hospital category. The absolute number of those operated on with an acute gallstone disease changed little between 1989 and 1994, whereas operations for chronic disease increased significantly. Stratification revealed that their risk of a long admission was increased both in 1989 and 1994, particularly for women. Those with chronic gallstone disease had no increased risk. After the introduction of the laparoscope and a rise in the number of cholecystectomies, patients with chronic gallstone disease seem to have a constant risk of long hospital stay. However, because patients with acute disease had an increased risk in both 1989 and 1994, further longitudinal analyses are needed to analyze the level of complications in this group.

Adult↗
PubMed2000

Audit and recurrence rates after hernia surgery.

OBJECTIVE: To study the effect of quality assurance on the recurrence rate after hernia repair. DESIGN: A prospective longitudinal cohort study. SETTING: District hospital, Sweden. SUBJECTS: All (n = 1232) patients aged 15-80 years operated upon for inguinal or femoral hernia in Motala 1984, 1986-1988, 1990, and 1992-1994. INTERVENTION: A questionnaire enquiring about pain or a lump in the operated area was sent 3-6 years postoperatively to all patients, excluding those who had already been operated on for recurrence and those who had died. Selected cases were examined depending on the answers to the questionnaire. MAIN OUTCOME MEASURES: Recurrence rate estimated by adding already confirmed recurrences to those found at the clinical examination; reoperation for recurrence; hospital stay; and number of day cases. Cumulative incidence of reoperation was analysed by actuarial analysis of all patients operated on from 1986-1997. RESULTS: The recurrence rate decreased from 18% in 1984 and 1986 to 3% in 1993 and 1994. The reoperation rate for recurrence at three years was 10.8% (95% confidence interval, CI: 9.3 to 12.2%), 3.6% (2.6 to 4.4%) and 2.2% (1.7 to 2.7%) for patients operated on between 1986-1988, 1989-1991 and 1992-1997, respectively. Differences between the first and the second and between the first and the third period were both highly significant (p < 0.001) whereas the difference between the second and third period was not (p = 0.09). Mean hospital stay decreased from 3.5 days in 1984 to 0.9 days in 1994. CONCLUSION: By recording recurrence rate or its surrogate endpoint, reoperation rate for recurrence, or both, hospital stay, and number of day cases, and presenting these results to participating surgeons, we provided incentives to improve outcome. This has resulted in a rapid decrease in recurrence rate and a shortened hospital stay, thereby improving cost-effectiveness.

Adolescent↗
PubMed2000

Electrolytes, water, RNA, total creatine and calculated resting membrane potential in muscle tissue from pregnant women.

BACKGROUND: The nutritional situation of the fetus and pregnant woman is important for human health, but knowledge of how nutrition affects maternal metabolism and physiology during pregnancy is limited. Such knowledge is important, for example in body composition studies, when information about lean tissue composition is needed. Muscle, a main part of lean tissue, changes its composition in response to age and sex, but the effect of pregnancy on this composition is unknown. METHODS: Muscle samples from 11 pregnant and 16 nonpregnant women were analyzed for water, electrolytes, total creatine, alkali-soluble protein (ASP), DNA and RNA. Plasma was analyzed for electrolytes. The amount of extracellular and intracellular water as well as the resting membrane potential (RMP) in muscle were calculated. RESULTS: Pregnant women had lower plasma concentrations of potassium and sodium but higher muscle concentrations of sodium and water (total and extracellular) than nonpregnant women. RMP was more negative in pregnant than in nonpregnant women. Total creatine in muscle (per kilogram ASP) was increased during pregnancy. The muscle content of RNA (per kilogram DNA) was lower in gestational week 18 than in nonpregnant controls. CONCLUSION: Pregnancy influences muscle composition in several ways that are relevant for an increased understanding of interactions between nutrition and reproduction.

Adult↗
PubMed2000

Body composition and muscle constituents during weight loss: studies in obese patients following gastroplasty.

BACKGROUND: The influence of rapid and prolonged weight loss on body composition and muscle constituents in the obese patient is not well known. There are serious complications related to rapid and prolonged weight loss. It is of general interest to increase the understanding of the mechanisms and consequences of significant weight loss in man. METHODS: In 40 obese patients, the body composition and muscle constituents were studied before and during 1 year of weight loss following gastroplasty. The study was undertaken in two groups (A and B) of obese patients, comprising 32 women and eight men, body weight 82-175 kg and aged 24-49 years. Mean BMI in group A and B was 45 (W/H(2)) and 43 (W/H(2)) respectively. Body composition was assessed by total body potassium measurements and muscle constituents were determined by analyses of muscle specimens obtained percutaneously. RESULTS: The preoperative body composition was found to be equal parts of lean body mass and body fat. Preoperatively, muscle constituents revealed a higher protein content per cell and a lower potassium concentration related to fat-free solids. The loss of 18-28% body fat and lean body mass occurred in equal proportions during the first 3 postoperative months of rapid weight loss, followed by a continuous decrease of body fat but not of lean body mass. The concentrations of proteins and potassium per muscle cell revealed a reduction during the period of rapid weight loss. The RNA/DNA ratio 1 year after surgery was still reduced, indicating a low protein synthesis rate. CONCLUSIONS: Preoperatively mean body fat accounted for 50% of the body weight in obese patients. Following weight loss, body fat, lean body mass and concentrations of proteins were reduced compared to preoperative values. After the period of rapid weight loss, with reduction of lean body mass and body fat in parallel, a progressive reduction of body fat was observed whereas the lean body mass did not decrease further. Protein synthesis rate was still low 12 months after surgery.

Adult↗
PubMed1999

Time-resolved fluorescence in immunocytochemical detection of prostate-specific antigen in prostatic tissue sections.

Chelates with fluorescent lanthanides such as europium and terbium are widely used in immunofluorometric assays, e.g. for the measurement of different molecular forms of prostate-specific antigen (PSA) in serum for detection and monitoring of prostate cancer. These chelates have also been introduced as non-radioactive labels in immunocytochemistry and in situ hybridization. In the present study, sections of non-malignant prostate were investigated using monoclonal IgGs against PSA. Detection of specific immunostaining employing time-resolved fluorescence with europium-labeled streptavidin was compared with conventional detection by streptavidin conjugated to horse-radish peroxidase. The high PSA concentration in the tissue produced high intensity, specific time-resolved fluorescence signals in the epithelial cells of the prostate gland without disturbance from non-specific tissue autofluorescense. This allowed short exposure times to be used which resulted in insignificant photobleaching. Two of the three europium-chelates evaluated yielded high signal intensities. Counterstaining was found to be optimal with Gill No. 1-Haematoxylin solution and Merckoglas was the best mounting medium for the europium chelates tested. In conclusion, time-resolved fluorescence imaging is an attractive alternative to conventional detection of streptavidin conjugated to horse-radish peroxidase, as it provides linear, high intensity, specific signals subsequent to the decay of non-specific tissue autofluorescence.

Aged↗