| 11. |
- Faxälv, Lars, et al.
(författare)
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Activation of blood coagulation at charged supported lipid membranes
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- The purpose of this work was to investigate the relationship between surface charge of phospholipid membranes and coagulation. Also, we wanted to demonstrate that coagulation at phospholipid membranes could successfully be studied in the method for imaging of coagulation.Analytical procedure: Supported phospholipid membranes were formed from palmitoyl-oleoyl-glycero-3-ethylphosphocholine (POEPC), 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC), and 1- palmitoyl-2-oleoyl-sn-glycero-3-[phospho-L-serine] (POPS) on silicon substrates. The surface charge of the phospholipid membranes was controlled by using different compositions of POPS (negative net charge), POPC (weak negative net charge) and POEPC (positive net charge). Imaging of coagulation experiments were performed on all phospholipid membrane coated surfaces as well as the clean silicon substrate. The experiments were performed in platelet-free plasma (PFP) diluted 50:50 with phosphate-buffered saline (PBS).Results: Comparing the negatively charged SiO2 surface with the negatively charged POPS (30%)/POPC(70%) we found an interesting difference. Although both surfaces activated coagulation rapidly, the POPS surface facilitated a faster propagation of coagulation from the surface than the SiO2 surface. It was also found that in order for the phospholipid membranes to exert procoagulant properties, the POPS content in the membrane had to exceed ~6 %. It was also found that positively charged phospholipid membranes did not induce activation of coagulation.Conclusions: The work in this paper demonstrated that the coagulation process at phospholipid membranes can be studied in a straightforward manner using the imaging of coagulation setup. Furthermore, we speculate that the negatively charged phospholipid membranes but not the SiO2 surface can support the binding of coagulation factor complexes, thus facilitating a faster propagation of coagulation. The fact that the POPS content must exceed ~ 6% to fully exert procoagulant properties was also a very interesting result, especially since platelets, when activated, become procoagulant by increasing their negatively charged phosphatidylserine exposure from ~0 % to maximally ~10 %.
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| 12. |
- Fröjse, Rolf, et al.
(författare)
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A new method for continuous tonometric pCO2 measurement : in vitro studies
- 1999
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Ingår i: Physiological Measurement. - : IOP Publishing. - 0967-3334 .- 1361-6579. ; 20:2, s. 129-136
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Tidskriftsartikel (refereegranskat)abstract
- 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 sructed 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
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| 13. |
- Fröjse, Rolf, et al.
(författare)
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Intestinal pHi studied with continuous saline tonometry during ischaemia and reperfusion in the pig.
- 2002
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Ingår i: European Journal of Vascular and Endovascular Surgery. - : Elsevier BV. - 1078-5884 .- 1532-2165. ; 24:2, s. 150-155
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To evaluate continuous saline tonometry for detection of progressive intestinal ischaemia and reperfusion in a porcine model. DESIGN: In eight anaesthetised pigs, small bowel mucosal pCO2 was recorded by means of two identical equipments for continuous saline tonometry and a standard tonometry balloon during ischaemia and reperfusion. RESULTS: Both systems of saline tonometry functioned stably during the four hour protocol ischaemia, although not significant until after 45 min for one of the tonometers. CONCLUSION: The equipment for continuous saline tonometry has a good reactivity, an accuracy comparable with standard tonometry.
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| 14. |
- Fröjse, Rolf, et al.
(författare)
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Validation of a novel method for continuous saline tonometry in a porcine model
- 2001
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Ingår i: Physiological Measurement. - : IOP Publishing. - 0967-3334 .- 1361-6579. ; 22:3, s. 453-460
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Tidskriftsartikel (refereegranskat)abstract
- Only intermittent and semi-continuous tonometric measurement of gastric and intestinal pHi is possible with the equipment available today. Earlier we developed a system for continuous saline tonometry and tested it in vitro. To assess the in vivo reliability of this method for continuous gastrointestinal saline tonometry, a standard tonometer for measurement of intestinal pCO2 and corresponding pHi was modified to allow continuous perfusion of physiological saline in a closed system and tested in a porcine model. In 11 anaesthetized and haemodynamically stable pigs, two continuous tonometry balloons were inserted into the distal small bowel, and a standard tonometry balloon was used as reference. To test long-term function of the continuous tonometers the research protocol lasted for eight hours. The two continuous saline tonometers performed well, and after an equilibration time of three hours the mean pHi values were stable between 7.35 and 7.43 and between 7.32 and 7.39 respectively. The standard tonometer measured stable pHi values. These preliminary studies indicate that continuous saline tonometry performs well over eight hours with a small bias and a good precision
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| 15. |
- Ghafouri, Bijar, et al.
(författare)
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Newly identified proteins in human nasal lavage fluid from non-smokers and smokers using two-dimensional gel electrophoresis and peptide mass fingerprinting
- 2002
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Ingår i: Proteomics. - 1615-9853 .- 1615-9861. ; 2:1, s. 112-120
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Tidskriftsartikel (refereegranskat)abstract
- Human nasal lavage fluids (NLFs) were analyzed with two-dimensional gel electrophoresis (2-DE) and proteins were identified with peptide mass fingerprinting using matrix-assisted laser desoption/ionization time of flight mass spectrometry. In some cases, the identification was verified by analysis of post-source decay fragmentation spectra. Many of the identified proteins were new forms or fragments of previously found proteins (e.g. albumin, lactoferrin, cystatin, calgranulin, von Ebners gland protein and palate lung nasal epithelium clone), while others were proteins that have previously been indicated by 2-DE image matching or immunoblots (e.g. apolipoprotein AI, lysozyme C, and Clara cell secretory protein). Some new proteins, not shown before in 2-DE patterns of NLF were also found, e.g. mammaglobin B, 2-microglobulin and immunoglobulin J chain. Of the identified NLF proteins many appear to be involved in inflammatory and immune responses. A study was therefore conducted to investigate if the levels of these proteins were changed in smokers compared to nonsmokers. It was found that NLF from smokers contained decreased levels of Clara cell secretory protein, and increased proportions of a truncated variant of lipocortin-1, three acidic forms of α1-antitrypsin, and one phosphorylated form of cystatin S. Furthermore, NLF from smokers contained increased proportions of a new variant of palate lung nasal epithelium clone (PLUNC), a recently identified airway irritation marker. The results demonstrate that 2-DE of NLF may be used to assess alterations of proteins or post-translationally modified proteins in smokers. Clara cell secretory protein (CC 16, CC 10) and lipocortin-1 are two anti-inflammatory, phospholipase A2 inhibitory proteins, and α1-antitrypsin and cystatin S are two proteinase inhibitors. Changed levels of these proteins may therefore be of importance to the airway inflammation caused by smoking. The results also support the notion that PLUNC is involved in inflammatory responses in the upper airways.
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| 16. |
- Ghafouri, Bijar, 1972-, et al.
(författare)
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PLUNC (palate, lung and nasal epithelial clone) proteins in human nasal lavage fluid
- 2003
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Ingår i: Biochemical Society Transactions. - 0300-5127 .- 1470-8752. ; 31:4, s. 810-814
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Tidskriftsartikel (refereegranskat)abstract
- PLUNC (palate, lung and nasal epithelial clone) is a newly discovered gene that is expressed in the upper respiratory tract and is suggested to be of importance in host defence against bacteria. We have identified two forms of the PLUNC protein in human nasal lavage fluid (NLF) using two-dimensional gel electrophoresis (2-DE) and MS. The apparent molecular masses and isoelectric points of these forms are 24.8 kDa/pI 5.4 and 25.1 kDa/pI 5.5. Notably, the 24.8 kDa/pI 5.4 form of PLUNC is an abundant protein in the 2-DE protein patterns of NLF from healthy subjects. Decreased levels of PLUNC were found in NLF from smokers and workers exposed to reactive epoxy chemicals, indicating that long-term exposure to airway irritants impairs the production of PLUNC in the upper respiratory tract. We have also investigated the presence of lipopolysaccharide (LPS)-binding proteins in NLF. Five proteins were found to adsorb to a LPS-coated surface; two of these proteins correspond to the two PLUNC forms, as judged by 2-DE pattern matching. For comparison, human saliva was found to contain a set of LPS-binding proteins with similar 2-DE spot positions (the same pIs but somewhat lower apparent molecular masses of 20 kDa). These results indicate that PLUNC may be a new marker of airway inflammation and may play a part in the innate immune response, and that human saliva contains yet other members of the family of LPS-binding proteins.
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| 17. |
- Hoffman, Tove, et al.
(författare)
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Diagnostic Potential of a Luminex-Based Coronavirus Disease 2019 Suspension Immunoassay (COVID-19 SIA) for the Detection of Antibodies against SARS-CoV-2
- 2021
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Ingår i: Viruses. - : MDPI. - 1999-4915. ; 13:6
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Tidskriftsartikel (refereegranskat)abstract
- Due to the current, rapidly increasing Coronavirus disease 2019 (COVID-19) pandemic, efficient and highly specific diagnostic methods are needed. The receptor-binding part of the spike (S) protein, S1, has been suggested to be highly virus-specific; it does not cross-react with antibodies against other coronaviruses. Three recombinant partial S proteins of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) expressed in mammalian or baculovirus-insect cells were evaluated as antigens in a Luminex-based suspension immunoassay (SIA). The best performing antigen (S1; amino acids 16-685) was selected and further evaluated by serum samples from 76 Swedish patients or convalescents with COVID-19 (previously PCR and/or serologically confirmed), 200 pre-COVID-19 individuals (180 blood donors and 20 infants), and 10 patients with acute Epstein-Barr virus infection. All 76 positive samples showed detectable antibodies to S1, while none of the 210 negative controls gave a false positive antibody reaction. We further compared the COVID-19 SIA with a commercially available enzyme immunoassay and a previously evaluated COVID-19 rapid antibody test. The results revealed an overall assay sensitivity of 100%, a specificity of 100% for both IgM and IgG, a quantitative ability at concentrations up to 25 BAU/mL, and a better performance as compared to the commercial assays, suggesting the COVID-19 SIA as a most valuable tool for efficient laboratory-based serology.
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| 18. |
- Hoffman, Tove, et al.
(författare)
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Evaluation of a COVID-19 IgM and IgG rapid test; an efficient tool for 4 assessment of past exposure to SARS-CoV-2
- 2020
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Ingår i: Infection Ecology & Epidemiology. - : Taylor & Francis. - 2000-8686. ; 10:1
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Tidskriftsartikel (refereegranskat)abstract
- COVID-19 is the most rapidly growing pandemic in modern time, and the need for 21 serological testing is most urgent. Although the diagnostics of acute patients by RT-PCR is 22 both efficient and specific, we are also crucially in need of serological tools for investigating 23 antibody responses and assessing individual and potential herd immunity. We evaluated a 24 commercially available test developed for rapid (within 15 minutes) detection of SARS-CoV-25 2-specific IgM and IgG by 29 PCR-confirmed COVID-19 cases and 124 negative controls. 26 The results revealed a sensitivity of 69.0 % and 93.1 % for IgM and IgG, respectively, based 27 solely on PCR-positivity due to the absence of a serological gold standard. The assay 28 specificities were shown to be 100 % for IgM and 99.2 % for IgG. This indicates that the test 29 is suitable for assessing previous virus exposure, although negative results may be unreliable 30 during the first weeks after infection. More detailed studies on antibody responses during and 31 post infection are urgently needed.
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| 19. |
- Hornum, Mads, et al.
(författare)
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Diagnosis, management and treatment of glucometabolic disorders emerging after kidney transplantation : a position statement from the Nordic Transplantation Societies
- 2013
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Ingår i: Transplant International. - : Frontiers Media SA. - 0934-0874 .- 1432-2277. ; 26:11, s. 1049-1060
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Forskningsöversikt (refereegranskat)abstract
- After successful solid organ transplantation, new-onset diabetes (NODAT) is reported to develop in about 15-40% of the patients. The variation in incidence may partly depend on differences in the populations that have been studied and partly depend on the different definitions of NODAT that have been used. The diagnosis was often based on 'the use of insulin postoperatively', 'oral agents used', random glucose monitoring and a fasting glucose value between 7 and 13 mmol/l (126-234 mg/dl). Only few have used a 2-h glucose tolerance test performed before transplantation. There is a huge variation in the literature regarding risk factors for developing NODAT. They can be divided into factors related to glucose metabolism or to patient demographics and the latter into modifiable and nonmodifiable. Screening for risk factors should start early and be re-evaluated while being on the waitlist. Patients on the waiting list for renal transplantation and transplanted patients share many characteristics in having hyperglycaemia, disturbed insulin secretion and increased insulin resistance. We present guidelines for early risk factor assessment and a screening/treatment strategy for disturbed glucose metabolism, both before and after transplantation. The aim was to avoid the increased cardiovascular disease and mortality rates associated with NODAT.
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| 20. |
- Högberg, Thomas, 1947-, et al.
(författare)
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A prospective population-based management program including primary surgery and postoperative risk assessment by means of DNA ploidy and histopathology. Adjuvant radiotherapy is not necessary for the majority of patients with FIGO stage I-II endometrial cancer
- 2004
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Ingår i: International Journal of Gynecological Cancer. - : BMJ. - 1048-891X .- 1525-1438. ; 14:3, s. 437-450
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Tidskriftsartikel (refereegranskat)abstract
- A management program for FIGO stage I-II nonserous, nonclear-cell adenocarcinomas was evaluated. Histopathology and DNA ploidy were used to estimate postoperatively the risk of progression or death of disease and to tailor treatment. The patient material was a population-based consecutive cohort of all women with endometrial cancer in the Southern Swedish Health Care Region diagnosed between June 1993 and June 1996 (n = 553). Of these, 335 were eligible for the management program. Patients estimated to be at low risk were treated by surgery only, while high-risk patients also received vaginal brachytherapy. A large low-risk group consisting of 84% (n = 283) of the patients with an estimated disease-specific 5-year survival of 96% (95% CI = 93-98%) was identified. The high-risk group (n = 52, 16%) showed a worse outcome with an 80% 5-year disease-specific survival (95% CI = 65-89%). The difference in survival between the groups was highly significant (P < 0.0001). Half of the progressions were distant in the high-risk group. Although there is a clear indication for adjuvant therapy for this group, locoregional radiotherapy could be expected to fail in cases with distant progression. Thus, effective systemic treatments need to be developed. Low-risk patients, constituting the majority (84%) of the patients, can be safely treated by surgery only.
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