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Staffan Nilsson

Publications and source records attributed to Staffan Nilsson.

At least 37 records · Page 2Linked to original sources
PubMed2005

Long-term results with tension-free vaginal tape on mixed and stress urinary incontinence.

OBJECTIVE: To compare outcome of the tension-free vaginal tape (TVT) procedure in women with urinary mixed and stress incontinence. METHODS: A mailed questionnaire was answered by 760 of 970 women who had undergone TVT surgery 2-8 years ago (78% response rate). Seventeen women had unclassified incontinence, and 51 women who developed de novo urgency were excluded, giving 580 (83.8%) with stress incontinence and 112 (16.2%) women with mixed incontinence eligible for analysis. Demographic, reproductive factors, and medical history were obtained. The questionnaire included detailed questions about urinary symptoms. Analysis of outcome was done for cohorts by number of years since the operation. RESULTS: The women with stress incontinence had a persistent cure rate of 85% from 2 to 8 years after the TVT procedure. The women with mixed incontinence had a persistent cure rate of 60% up to 4 years postoperatively, but the cure rate then steadily declined to 30% from 4 to 8 years after surgery. The increased rate of incontinence was due to urgency symptoms. CONCLUSION: The results of this study indicate that initial good cure rates of TVT for mixed incontinence do not persist after 4 years. LEVEL OF EVIDENCE: III.

Aged↗
PubMed2005

Sleep apnea and hormone replacement therapy: a pilot study and a literature review.

BACKGROUND: Sleep apnea syndrome (SAS) is a common condition and a risk factor of cardiovascular and cerebrovascular diseases. The purpose of this pilot study was to investigate the effect of a gestagen (trimegeston) and estradiol hormone combination on perimenopausal and postmenopausal women with SAS. METHODS: Four postmenopausal and one perimenopausal women were studied by polysomnography before and after treatment with hormone replacement therapy (HRT). RESULTS: The subjects had a mean reduction of the severity of their sleep apnea by 75% measured by apnea/hypopnea index. CONCLUSIONS: HRT might be an alternative in the treatment of SAS.

Estradiol↗
PubMed2004

Nanospray mass spectrometry with indirect conductive graphite coating.

An easy and cost-effective method to manufacture a robust conductive graphite coating for nanospray mass spectrometry (nESI-MS) and capillary electrophoresis (CE)-nESI-MS is described. The method involves graphite coating of a tube sleeve, into which the nESI emitter is inserted and connected to a transfer capillary, instead of coating the actual emitter. The coating, made of graphite from a pencil and epoxy glue, was stable over long periods of use (>80 h) and showed excellent resistance toward various solvents. Stable electrospray was achieved in the investigated flow range (150-900 nL x min(-)(1)), and salbutamol, diphenhydramine, and nortriptyline (M(w): 239-263 g x mol(-)(1)) were detected in the nanomole per liter range during continuous pumping. CE-nESI-MS analysis gave excellent signal-to-noise ratios for 100-fmol injections. The technique allows simple exchange of the nESI emitter to suit a specific flow rate, and it minimizes risk of corona discharge.

Journal Article↗
PubMed2004

Laser techniques in acoustically levitated micro droplets.

Laser techniques were applied to an acoustically levitated droplet for remote investigation of the diameter, species concentration and temperature of the suspended droplet. To this end, the third and the fourth harmonic of a Nd:YAG laser were used for investigation of elastic, fluorescence and phosphorescence signals from the droplet. The droplet was seeded with thermographic phosphors and acetone for the phosphorescence and fluorescence measurements, respectively. The techniques were applied simultaneously using an imaging stereoscope. The imaging device allowed for an identical visualization of incoming signal through separate optical filters. Temperature measurements in droplets is important in the study of e.g. exothermic chemical reactions, spray processes, combustion, and in bioanalytical applications where the biological material is temperature sensitive or dependent on optimal temperature for function. Results from these investigations showed that temperature measurements in acoustically levitated droplets using laser-induced phosphorescence are feasible. The results also show the potential of simultaneous laser based measurements on levitated droplets. Diameter variation (surface area), mixture concentration and temperature were measured simultaneously.

Lasers↗
PubMed2004

Molecularly imprinted polymer formats for capillary electrochromatography.

The research aimed towards the adaptation of molecularly imprinted polymers (MIPs) to the capillary format and the use of these highly selective matrices for capillary electrochromatography (CEC) is reviewed in this article. The MIP is prepared by incorporation of a template molecule into a polymerization protocol. After polymerization and extraction of the template from the resulting polymer a highly selective material with recognition cavities complementary to the template in size, shape and chemical functionality is obtained. MIPs have been used as recognition elements in several different analytical techniques. In combination with CEC a novel separation system with a unique selectivity towards a predetermined target (the template) is achieved. The merge of molecular imprinting technology (MIT) and CEC have introduced several interesting polymer formats, due to the adaptation of the MIP to the miniaturized capillary format. The polymer formats can be classified according to their preparation protocols and appearance into three conceptually different categories, i.e. the monolith, the coating and the nanoparticles. The preparation protocols, characteristics and applications of these formats will be discussed.

Chromatography, Micellar Electrokinetic Capillary↗
PubMed2004

Airborne chemistry: acoustic levitation in chemical analysis.

This review with 60 references describes a unique path to miniaturisation, that is, the use of acoustic levitation in analytical and bioanalytical chemistry applications. Levitation of small volumes of sample by means of a levitation technique can be used as a way to avoid solid walls around the sample, thus circumventing the main problem of miniaturisation, the unfavourable surface-to-volume ratio. Different techniques for sample levitation have been developed and improved. Of the levitation techniques described, acoustic or ultrasonic levitation fulfils all requirements for analytical chemistry applications. This technique has previously been used to study properties of molten materials and the equilibrium shape()and stability of liquid drops. Temperature and mass transfer in levitated drops have also been described, as have crystallisation and microgravity applications. The airborne analytical system described here is equipped with different and exchangeable remote detection systems. The levitated drops are normally in the 100 nL-2 microL volume range and additions to the levitated drop can be made in the pL-volume range. The use of levitated drops in analytical and bioanalytical chemistry offers several benefits. Several remote detection systems are compatible with acoustic levitation, including fluorescence imaging detection, right angle light scattering, Raman spectroscopy, and X-ray diffraction. Applications include liquid/liquid extractions, solvent exchange, analyte enrichment, single-cell analysis, cell-cell communication studies, precipitation screening of proteins to establish nucleation conditions, and crystallisation of proteins and pharmaceuticals.

Journal Article↗
PubMed2004

In-capillary micro solid-phase extraction and capillary electrophoresis separation of heterocyclic aromatic amines with nanospray mass spectrometric detection.

A miniaturised technique to analyse and detect heterocyclic aromatic amines (HAs) using micro solid-phase extraction ( microSPE) coupled on-line (in-capillary) to capillary electrophoresis (CE) separation with nanospray (nESI) mass spectrometry (MS) detection has been developed. HAs are mutagenic and carcinogenic compounds formed at low levels in protein-rich food during cooking. Due to the low concentrations of HAs and the high complexity of the matrix in which they exist, sensitive and selective analytical methods are required for quantification. microSPE was performed on a packed bed of C(18 )particles inside the CE capillary, which minimised the dead volume. The on-line coupling of SPE, CE and nESI-MS reduced the time for extraction and identification to less than half an hour, which will allow for screening of several samples per day. The new technique provides short analysis time, low sample and solvent consumption, and HAs in standard solutions were easily detected at 12-17 fmol injections, and in spiked urine samples at 750-810 fmol injections.

Journal Article↗
PubMed2004

Affinity two-phase partitioning in acoustically levitated drops.

Miniaturized (<1 microL) biospecific affinity two-phase partitioning in an acoustically levitated drop is described. Miniaturization commonly gives unfavorable surface/volume ratios, but in the levitation approach adsorption problems are minimized since the only surrounding wall is the liquid/air interface of the drop. Biotinylated liposomes were partitioned in aqueous poly(ethylene glycol)/dextran two-phase drops with NeutrAvidin-dextran as the affinity ligand. A two-phase drop was trapped and manipulated in a node of a standing ultrasonic wave. Alternatively, a two-phase system was formed by levitation and evaporation of a polymer one-phase drop. Phase mixing was achieved by adjusting the ultrasonic field and phase separation by readjusting the field. NeutrAvidin-dextran brought about the redistribution of biotinylated liposomes from the poly(ethylene glycol)-rich phase into the dextran-rich phase. Thus, an entire affinity two-phase separation procedure, including mixing of the phases and incubation to allow affinity interactions to develop under constant volume, followed by phase separation under controlled evaporation, can be performed in a single levitated drop. This miniaturized technique would allow the separation of biologically active membranes or organelles from individual cells for analysis.

Journal Article↗
PubMed2004

Some life-style factors and the risk of invasive epithelial ovarian cancer in Swedish women.

The objective of this nationwide case-control study was to examine body mass index (BMI), alcohol use, coffee consumption, cigarette smoking, and leisure-time physical activity in relation to epithelial ovarian cancer (EOC) risk. Subjects were 655 newly diagnosed EOC cases and 3899 population controls, all 50-74 years of age at recruitment between 1993 and 1995. Data were collected through mailed questionnaires. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using unconditional logistic regression. Women with a BMI > or = 30 kg/m2 compared with those with a BMI < 22 kg/m2 appeared to have an elevated EOC risk (OR = 1.37, 95% CI: 1.01-1.85), particularly of mucinous (OR = 2.76, 95% CI: 1.15-6.61) and clear-cell histologies (OR = 2.68, 95% CI: 0.96-7.48). The OR for EOC among coffee users reporting > or = 6 daily cups compared with non-users was 0.68 (95% CI: 0.42-1.10). Alcohol consumption was unrelated to EOC risk. Compared to non-smokers the ORs of EOC among current smokers were 0.70 (95% CI: 0.52-0.94) for those who smoked 1-10 cigarettes/day and 0.74 (95% CI: 0.53-1.02) for heavier smokers, while former smokers were at an unaltered risk (OR = 0.83, 95% CI: 0.66-1.04). Reduced EOC risks were observed among women in the highest compared with the lowest physical activity levels both at age 18-30 years (OR = 0.67, 95% CI: 0.52-0.87) and during the last years preceding study enrollment (OR = 0.68, 95% CI: 0.53-0.87). We conclude that women may avoid an excess risk of EOC through maintaining a normal BMI and reduce their risk by participation in leisure-time physical activity. The use of coffee, alcohol, or cigarette smoking does not appear to increase the risk of EOC.

Aged↗
PubMed2004

Low-dose aspirin in a short regimen as standard treatment in in vitro fertilization: a randomized, prospective study.

OBJECTIVE: To determine if treatment with low-dose aspirin in a short regimen improves the outcome in a nonselected IVF population as compared with no treatment. DESIGN: Prospective, randomized study where IVF patients were given aspirin or received no treatment. SETTING: IVF clinic. PATIENT(S): The study included 1380 consecutive IVF cycles. INTERVENTION(S): Women undergoing IVF were randomly assigned to treatment with aspirin 75 mg daily from the day of embryo transfer (ET) until pregnancy test or no treatment in an open study. MAIN OUTCOME MEASURE(S): Birth rate per ET. RESULT(S): Background characteristics were similar in the two groups studied except for a minor difference in number of embryos transferred (2.1 vs. 2.0). Birth rate was 27.2% in the aspirin group as compared with 23.2% in the nontreated group, giving an odds ratio, adjusted for number of embryos transferred, of 1.2 (95% confidence interval, 1.0-1.6). CONCLUSION(S): The increased birth rate with aspirin compared with no treatment was significant. Given the importance of every birth in IVF, especially when taking into account the limited number of IVF cycles that are normally performed in an individual woman, any treatment to improve birth rate is important.

Adult↗
PubMed2004

Association between a functional polymorphism in the progesterone receptor gene and panic disorder in women.

Although genetic factors are known to be important risk factors for panic disorder there is as yet no conclusive data regarding specific gene variants. Prompted by evidence supporting progesterone to influence the pathophysiology of panic disorder, polymorphisms in the progesterone receptor gene, a single nucleotide polymorphism (G331A) and an insertion/deletion polymorphism (PROGINS) were investigated in 72 patients with panic disorder and 452 controls. The frequency of the A-allele of the G331A polymorphism was higher in panic disorder patients than in controls (p = 0.01). When male and female patients were analyzed separately, the association was observed in female patients only (p = 0.0009), with an odds ratio of 3.5. No differences between groups were observed for the PROGINS polymorphism. In conclusion, these data suggest that the G331A polymorphism in the progesterone receptor gene may influence the risk for panic disorder in women.

Chromosomes, Human, Pair 11↗
PubMed2004

The risk of celiac disease in 107 families with at least two affected siblings.

OBJECTIVES: Screening for celiac disease (CD) in the apparently healthy members of 107 nuclear families with two affected siblings (sib pair) and estimating the risk of CD in siblings and parents. METHODS: One hundred seven families from Sweden and southern Norway with at least two affected children were investigated. Frozen sera from 187 of the 192 healthy parents and from 94 of 95 siblings without diagnosed CD were examined for total immunoglobulin A (IgA) and anti-endomysial antibodies (EMA). Individuals with positive antibody titers underwent small intestinal biopsy. RESULTS: Positive test for EMA was found in 6 of 94 (6.3%) siblings without previously diagnosed CD and in 8 of 189 (4.2%) parents. CD was confirmed by small intestinal biopsy in all siblings and seven parents. The estimated risk for CD in multiply affected families was 26.3% for siblings and 12.9% for parents. An unexpected male preponderance was found among the new CD cases (10 males, 3 females). CONCLUSION: The risk of CD in the members of nuclear families with two affected children is approximately three times higher than that when only one child is affected. The high male preponderance of new cases is unexpected and could not be explained fully by more silent disease in males as compared with females. Considering the high level of knowledge about CD in these families, the number of undiagnosed cases is surprisingly high. The authors suggest that serologic screening should be offered to all first-degree relatives of patients with CD.

Adolescent↗
PubMed2004

Review of epidemiological evidence for reproductive and hormonal factors in relation to the risk of epithelial ovarian malignancies.

Ovarian cancer is the leading cause of mortality related to gynecologic malignancies in Sweden but there is no current screening program. Based upon epidemiological research there is evidence that certain reproductive factors are associated with ovarian cancer risk. Most studies generally indicate that each childbirth incurs a 15-20% risk reduction. Women who have used oral contraceptives for 5 years or longer experience about half the risk of ovarian cancer compared with never users. Breastfeeding seems to be protective while age at menarche and at menopause are less consistent risk predictors. Tubal ligation and hysterectomy seem to reduce ovarian cancer risk by up to 80%. Although some studies found endometriosis, polycystic ovarian syndrome (PCOS) and pelvic inflammatory disease (PID) to be positively related to ovarian cancer, the role of these factors is not yet established. Most recent studies observed an approximately 50% ovarian cancer risk increase among ever users of hormone replacement therapy (HRT) compared with never users, and the risk increased further with long-term use. There is less information concerning separate estrogen and progestin effects of HRT and ovarian cancer risk. Although the cause of ovarian cancer remains obscure, hypotheses relating to "incessant" ovulation, excessive gonadotropin secretion, retrograde carcinogen transportation, apoptosis and estrogen/progestin imbalance have been invoked as etiological explanations. All these hypotheses find various epidemiological support. The aim of this review is to summarize the epidemiological findings on reproductive factors and ovarian cancer risk. These findings are considered in the context of etiologic hypotheses and some new research areas are suggested.

Adult↗
PubMed2004

Polymorphisms in oestrogen and progesterone receptor genes: possible influence on prolactin levels in women.

OBJECTIVE: Oestrogen and progesterone are known to influence the release of human prolactin. The present study was undertaken in order to investigate the possible influence of polymorphisms of the genes encoding the oestrogen receptor (ER)alpha, ERbeta and the progesterone receptor (PGR), on prolactin levels in premenopausal women. DESIGN AND MEASUREMENTS: Serum levels of prolactin were measured in the follicular phase of the menstrual cycle. Subjects were genotyped with respect to a TA repeat polymorphism of the ERalpha gene, a CA repeat polymorphism of the ERbeta gene, and two polymorphisms of the PGR gene: one insertion polymorphism (PROGINS) and one single nucleotide polymorphism (G331A). SUBJECTS: A population-based cohort of 270 42-year-old women. RESULTS: The CA repeat polymorphism of the ERbeta gene and the G331A polymorphism of the PGR gene appeared to be associated with prolactin levels. In contrast, we found no evidence for an influence of the PROGINS polymorphism of the PGR gene or the TA repeat polymorphism of the ERalpha gene on the levels of this hormone. CONCLUSIONS: These data suggest that genetic variants of both the ERbeta and the PGR may influence prolactin release.

Adult↗