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Persson A, Lingström P, Bäcklund T, van Dijken JWV. Evaluation of a skin reference electrode used for intraoral pH measurements in combination with a microtouch electrode. Clin Oral Investig 2004; 8:172-5. [PMID: 14963726 DOI: 10.1007/s00784-004-0257-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2003] [Accepted: 01/22/2004] [Indexed: 10/26/2022]
Abstract
The aim of this in vivo study was to evaluate a skin reference electrode used with the microtouch method for measurements of intraoral pH. Registrations of plaque pH were made in ten healthy subjects before and up to 30 min after a mouth rinse with 10% sucrose. A microtouch electrode (Beetrode) was used in combination with two different half-cell reference electrodes: a skin silver-silver chloride plate or a glass capillary reference electrode. The skin electrode was placed on the subject's forearm in combination with a conductive gel. The glass capillary electrode, together with one of the test subject's fingers, was placed in a beaker with a 3 M KCl solution. High agreement between the two reference systems resulted in almost identical plaque-pH curves (r=0.97). The mean differences between the two systems at the different time points varied between -0.15 and +0.01 pH units, with an overall mean pH difference of 0.03 pH units. It can be concluded that the use of the skin reference electrode may very well replace the traditional reference electrode used in combination with a microtouch electrode for intraoral use.
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Oluwole OSA, Onabolu AO, Cotgreave IA, Rosling H, Persson A, Link H. Incidence of endemic ataxic polyneuropathy and its relation to exposure to cyanide in a Nigerian community. J Neurol Neurosurg Psychiatry 2003; 74:1417-22. [PMID: 14570837 PMCID: PMC1757397 DOI: 10.1136/jnnp.74.10.1417] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND The occurrence of ataxic polyneuropathy in an endemic area in south west Nigeria has been attributed to exposure to cyanide from cassava foods. However, it has been shown that the prevalence of ataxic polyneuropathy is not high in several communities in the tropics where exposure to cyanide from cassava foods is high. OBJECTIVES To determine the incidence of ataxic polyneuropathy in an endemic community, and to compare the intake of cassava foods, exposure to cyanide, and levels of thiols in cases and controls. METHODS A cohort of 3167 healthy subjects aged 10 years and over in Ososa, Nigeria, was followed for two years, screened, and examined neurologically. Ataxic polyneuropathy was diagnosed if sensory polyneuropathy and sensory gait ataxia were both present. Controls were selected randomly within 10 year age groups of subjects who screened negative. Intake of cassava foods, exposure to cyanide, concentrations of thiols (glutathione, cysteine, and gamma glutamylcysteine) in plasma, and visual evoked potentials were measured. RESULTS Person-years of follow up were 6246 for 1469 male and 1698 female subjects in the cohort. The incidence of ataxic polyneuropathy was 64 per 10,000 person-years (31 for male and 93 for female subjects). Multivariate odd ratios were 0.78 (95% CI 0.23 to 2.61) for intake of the commonest cassava food, and 1.64 (0.56 to 5.09) for concentration of thiocyanate in plasma. The concentration of thiols was less than the reference limits in two controls, but in none of the cases. The latency of P100 was prolonged in 20 cases (69%) compared with 14 controls (42%) (p<0.05). CONCLUSIONS The incidence of ataxic polyneuropathy is high in Ososa, Nigeria, but the intake of cassava foods, exposure to cyanide, and levels of thiols, are not related to the occurrence. These findings do not suggest that cyanide is the cause of endemic ataxic polyneuropathy.
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Hultén F, Persson A, Eliasson-Selling L, Heldmer E, Lindberg M, Sjögren U, Kugelberg C, Ehlorsson CJ. Clinical characteristics, prevalence, influence on sow performance, and assessment of sow-related risk factors for granulomatous mastitis in sows. Am J Vet Res 2003; 64:463-9. [PMID: 12693537 DOI: 10.2460/ajvr.2003.64.463] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To determine the prevalence and clinical appearance of granulomatous mastitis in sows, to identify sow-related risk factors for development of granulomatous mastitis, and to explore the manner in which the disease influences sow performance. ANIMALS 1,254 sows from 76 herds. PROCEDURE A clinical examination was performed at time of weaning and 7 days later. In addition, some sows were reexamined at time of weaning in the subsequent lactation. Data were collected on sow performance. RESULTS At time of weaning, 205 of 1,254 (16%) sows had granulomatous mastitis, and 7 days later, the prevalence was 19%. Variation between herds was large (0 to 50%). In most of the affected sows (156/205 176%]), only 1 mammary gland was affected. Parity, duration of lactation, and number of teat wounds were identified as risk factors for development of the disease. In 264 of 559 (47%) sows (38/104 [37%] mammary glands), a granuloma recurred in the subsequent lactation. Risk for recurrence was related granuloma appearing in multiple form but not to granuloma size. Affected glands were less distended in the subsequent lactation, suggesting lower milk production. Litter size appeared to be negatively affected by the disease. CONCLUSIONS AND CLINICAL RELEVANCE Granu lomatous mastitis is a common disease in sow herds maintained on straw bedding and in group housing, and it has negative effects on sow productivity. A thorough description of the clinical appearance of the disease and the identification of risk factors should contribute to development of relevant control measures.
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Engellau L, Albrechtsson U, Dahlström N, Norgren L, Persson A, Larsson EM. Measurements before endovascular repair of abdominal aortic aneurysms. MR imaging with MRA vs. angiography and CT. Acta Radiol 2003. [PMID: 12694105 DOI: 10.1034/j.1600-0455.2003.00029.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
PURPOSE 1) To compare measurements obtained with MR imaging (MRI)/contrast-enhanced MR angiography (CE MRA) with measurements obtained with angiography (DSA) and CT, for stent-graft sizing of abdominal aortic aneurysms (AAA). 2) To compare MRA measurements obtained with the two post processing techniques MIP (maximum intensity projection) and VRT (3D volume rendering technique). MATERIAL AND METHODS The prospective study included 20 consecutive patients with AAA identified by DSA and CT as suitable for endovascular repair. For the study, MRI/CE MRA was performed. Five measurement variables for stent-graft sizing were chosen. Comparisons were made between MRI/CE MRA, DSA and CT, and between observers. Comparisons were also made between MIP and VRT. RESULTS Significantly shorter lengths were obtained with MRA-MIP than with DSA. Three out of six diameter measurements were significantly smaller on MRI/CE MRA than on DSA and CT. No significant differences were found between the observers. One diameter measurement was significantly smaller on MIP than on VRT, while the other measurements showed no significant differences. CONCLUSION The length measurements obtained with MRA-MIP were probably more correct than those with DSA. For more reliable diameter measurements with CE MRA, improvements of the technique, including VRT reconstructions and a standardized determination of the vessel boundaries, are needed.
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Engellau L, Albrechtsson U, Dahlström N, Norgren L, Persson A, Larsson EM. Measurements before endovascular repair of abdominal aortic aneurysms. MR imaging with MRA vs. angiography and CT. Acta Radiol 2003; 44:177-84. [PMID: 12694105 DOI: 10.1080/j.1600-0455.2003.00029.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/20/2023]
Abstract
PURPOSE 1) To compare measurements obtained with MR imaging (MRI)/contrast-enhanced MR angiography (CE MRA) with measurements obtained with angiography (DSA) and CT, for stent-graft sizing of abdominal aortic aneurysms (AAA). 2) To compare MRA measurements obtained with the two post processing techniques MIP (maximum intensity projection) and VRT (3D volume rendering technique). MATERIAL AND METHODS The prospective study included 20 consecutive patients with AAA identified by DSA and CT as suitable for endovascular repair. For the study, MRI/CE MRA was performed. Five measurement variables for stent-graft sizing were chosen. Comparisons were made between MRI/CE MRA, DSA and CT, and between observers. Comparisons were also made between MIP and VRT. RESULTS Significantly shorter lengths were obtained with MRA-MIP than with DSA. Three out of six diameter measurements were significantly smaller on MRI/CE MRA than on DSA and CT. No significant differences were found between the observers. One diameter measurement was significantly smaller on MIP than on VRT, while the other measurements showed no significant differences. CONCLUSION The length measurements obtained with MRA-MIP were probably more correct than those with DSA. For more reliable diameter measurements with CE MRA, improvements of the technique, including VRT reconstructions and a standardized determination of the vessel boundaries, are needed.
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Öberg PÅ, Persson A, Sjöstrand U. A high input impedance, low level d.c. amplifier utilizing a solid-state operational amplifier. ACTA ACUST UNITED AC 2002. [DOI: 10.1088/0950-7671/44/10/417] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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82
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Watson JB, Khorasani H, Persson A, Huang KP, Huang FL, O'Dell TJ. Age-related deficits in long-term potentiation are insensitive to hydrogen peroxide: coincidence with enhanced autophosphorylation of Ca2+/calmodulin-dependent protein kinase II. J Neurosci Res 2002; 70:298-308. [PMID: 12391589 DOI: 10.1002/jnr.10427] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Reactive oxygen species (ROS) can have deleterious effects for both normal aging and Alzheimer's disease (AD). We examined the hypothesis that synapses undergoing long-term potentiation (LTP) are preferentially at risk for ROS-mediated oxidative stress during aging. We observed age-dependent deficits in LTP induced by a high-frequency stimulation (HFS) protocol in the CA1 region of hippocampus from C57BL/6 mice. There was a significant difference between LTP measured over 60 min in young (1-2 months) and old (23-26 months) mice. In oxidative stress studies, exogenous H(2)O(2) (580 micro M) significantly inhibited LTP in young mice; a similar dose of H(2)O(2) failed to inhibit LTP in slices from adult (2-4 months) or from old mice. The results show that there are significant deficits in LTP in aging mice, but such deficits are insensitive to H(2)O(2). Western immunoblotting studies in young mice show that the relative levels of autophosphorylated alpha-Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) are unchanged in hippocampal CA1 treated with H(2)O(2) relative to untreated controls. However with aging, there is a significant enhancement in the levels of autophosphorylated CaMKII in H(2)O(2)-treated CA1 of older mice. Phosphorylation of RC3/neurogranin (Ng) by protein kinase C (PKC) is decreased in CA1 in response to H(2)O(2) treatment, irrespective of age. We propose that, during aging, enhanced local release of H(2)O(2) from mitochondria may induce a compensatory "ceiling" effect at synapses, so that the levels of autophosphorylated alpha CaMKII are aberrantly saturated, leading to alterations in synaptic plasticity.
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Oluwole OSA, Onabolu AO, Cotgreave IA, Rosling H, Persson A, Link H. Low prevalence of ataxic polyneuropathy in a community with high exposure to cyanide from cassava foods. J Neurol 2002; 249:1034-40. [PMID: 12195450 DOI: 10.1007/s00415-002-0779-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
INTRODUCTION Ataxic polyneuropathy, which occurs in endemic form in an area in southwest Nigeria, is attributed to exposure to cyanide from cassava foods. Exposure to cyanide from cassava is, however, not exclusive to this endemic area. In this study, the occurrence of ataxic polyneuropathy was compared in two communities in Nigeria, one located in the endemic area and the other located outside the endemic area. Both communities have been shown to have high exposure to cyanide from cassava foods. METHOD The prevalence of ataxic polyneuropathy in Jobele, Nigeria, a community located outside the endemic area, was compared with the prevalence of ataxic polyneuropathy in Ososa, Nigeria, a reference community located in the endemic area. Subjects aged 10 years and above in both communities were screened for ataxic polyneuropathy. Ataxic polyneuropathy was diagnosed if sensory gait ataxia and sensory polyneuropathy were present. The intake of cassava foods, biomarkers of exposure to cyanide, and intake of protein and sulphur were measured. RESULTS Prevalence of ataxic polyneuropathy were 490 per 10,000 in Ososa, and 17 per 10,000 in Jobele. The age-adjusted prevalence ratio is 4 (95% CI 0-9). The mean intake of all cassava foods in Jobele was 7 meals/person/week (95% CI 6-8), while the mean intake of all cassava foods in Ososa was 10 meals/person/week (95 % CI 9-11). The concentration of thiocyanate in the plasma was above the reference limit in 65% (95% CI 57-73) in Jobele, and 40 % (95% CI 27-52) in Ososa. The intake of protein was significantly lower in Ososa than in Jobele, but the concentrations of glutathione, cysteine and gamma-glutamylcysteine in the plasma were within the same range in Jobele and Ososa. CONCLUSION This study shows that the occurrence of ataxic polyneuropathy is low in a community where exposure to cyanide is high. This suggests that exposure to cyanide is not a direct cause of ataxic polyneuropathy.
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Bolinder J, Sjöberg S, Persson A, Ahrén B, Sundkvist G. Autonomic neuropathy is associated with impaired pancreatic polypeptide and neuropeptide Y responses to insulin-induced hypoglycaemia in Type I diabetic patients. Diabetologia 2002; 45:1043-4. [PMID: 12187924 DOI: 10.1007/s00125-002-0821-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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85
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Norin J, Mauritsson J, Johansson A, Raarup MK, Buil S, Persson A, Dühr O, Gaarde MB, Schafer KJ, Keller U, Wahlström CG, L'Huillier A. Time-frequency characterization of femtosecond extreme ultraviolet pulses. PHYSICAL REVIEW LETTERS 2002; 88:193901. [PMID: 12005632 DOI: 10.1103/physrevlett.88.193901] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2001] [Indexed: 05/19/2023]
Abstract
We present energy-resolved cross-correlation measurements of an extreme ultraviolet (XUV) pulse, generated as the fifth harmonic (15.5 eV) of an intense 80 fs laser pulse centered at 400 nm. Spectrally resolving the cross-correlation signal allows us to characterize the time-dependent frequency of the XUV pulse. We find that the fifth harmonic has a small negative chirp in excess of that predicted by perturbation theory. In addition, by manipulating the chirp of the driving laser we can induce and measure a positive or a negative chirp on the XUV pulse.
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86
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Persson A, Johansson M, Jansson T, Powell TL. Na(+)/K(+)-ATPase activity and expression in syncytiotrophoblast plasma membranes in pregnancies complicated by diabetes. Placenta 2002; 23:386-91. [PMID: 12061854 DOI: 10.1053/plac.2002.0807] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Many of the transport processes across the syncytiotrophoblast (ST), such as amino acid transport, are Na(+)-coupled. The maintenance of a low intracellular Na(+) concentration by Na(+)/K(+)-ATPase is therefore crucial for placental transport of nutrients and consequently, foetal growth. In pregnancies complicated by diabetes foetal growth is often accelerated despite rigorous glycemic control of the mother, however the underlying mechanisms are not fully understood. We tested the hypothesis that Na(+)/K(+)-ATPase in ST plasma membranes is up-regulated in diabetic pregnancies associated with accelerated growth. ST microvillous (MVM) and basal (BM) plasma membranes were purified from term placentas of normal pregnancies (control, n=13) and pregnancies complicated by insulin-dependent diabetes mellitus (n=7) or gestational diabetes (n=6). All mothers with diabetes gave birth to large for gestational age babies. The Na(+)/K(+)-ATPase alpha(1)-subunit protein expression (Western blot) in MVM and BM was unaltered by diabetes. Na(+)/K(+)-ATPase activity (K(+)-stimulated, ouabain-sensitive phosphatase activity) in ST plasma membranes was not affected by diabetes. This is the first study of Na(+)/K(+)-ATPase in ST membranes of the human placenta in diabetes. Our data show that accelerated foetal growth in diabetic pregnancies is not associated with elevated ST Na(+)/K(+)-ATPase protein expression or activity.
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Gulbinas V, Chachisvilis M, Persson A, Sundstroem V, Svanberg S. Ultrafast Excitation Relaxation in Colloidal Particles of Chloroaluminum Phthalocyanine: One-Dimensional Exciton-Exciton Annihilation. ACTA ACUST UNITED AC 2002. [DOI: 10.1021/j100084a032] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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88
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Ling G, Ahmadian A, Persson A, Undén AB, Afink G, Williams C, Uhlén M, Toftgård R, Lundeberg J, Pontén F. PATCHED and p53 gene alterations in sporadic and hereditary basal cell cancer. Oncogene 2001; 20:7770-8. [PMID: 11753655 DOI: 10.1038/sj.onc.1204946] [Citation(s) in RCA: 350] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2001] [Revised: 08/22/2001] [Accepted: 09/04/2001] [Indexed: 11/08/2022]
Abstract
It is widely accepted that disruption of the hedgehog-patched pathway is a key event in development of basal cell cancer. In addition to patched gene alterations, p53 gene mutations are also frequent in basal cell cancer. We determined loss of heterozygosity in the patched and p53 loci as well as sequencing the p53 gene in tumors both from sporadic and hereditary cases. A total of 70 microdissected samples from tumor and adjacent skin were subjected to PCR followed by fragment analysis and DNA sequencing. We found allelic loss in the patched locus in 6/8 sporadic basal cell cancer and 17/19 hereditary tumors. All sporadic and 7/20 hereditary tumors showed p53 gene mutations. Loss of heterozygosity in the p53 locus was rare in both groups. The p53 mutations detected in hereditary tumors included rare single nucleotide deletions and unusual double-base substitutions compared to the typical ultraviolet light induced missense mutations found in sporadic tumors. Careful microdissection of individual tumors revealed genetically linked subclones with different p53 and/or patched genotype providing an insight on time sequence of genetic events. The high frequency and co-existence of genetic alterations in the patched and p53 genes suggest that both these genes are important in the development of basal cell cancer.
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Lundqvist G, Persson A, Widman L, Lundgren R, Lindén G. [Chronic obstructive lung disease. Early diagnosis in primary health care requires well-functioning spirometry routines]. LAKARTIDNINGEN 2001; 98:4702-3. [PMID: 11715246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/17/2023]
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90
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Persson A, Wanek B, Johansson A. Passive versus active operator work in automated process control--a job design case study in a control centre. APPLIED ERGONOMICS 2001; 32:441-451. [PMID: 11534789 DOI: 10.1016/s0003-6870(01)00022-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Methods of avoiding common problems associated with operator work in automated process control, such as understimulation and difficulties in achieving and maintaining necessary skills and competence, are addressed in this paper. The source of these problems is deduced here to be that monitoring tasks are a predominant part of the job. This case study shows how work in a highly automated process can be designed not only to avoid the traditional problems, but also provide a stimulating job within a good work situation at the same time as fulfilling efficiency demands. A new definition of active/passive operator jobs is made which is based on a categorisation of the types of work tasks that make up the job. The definition gives an explanation of how different designs of operator jobs result in more or less active/passive work situations.
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Ling G, Persson A, Berne B, Uhlén M, Lundeberg J, Ponten F. Persistent p53 mutations in single cells from normal human skin. THE AMERICAN JOURNAL OF PATHOLOGY 2001; 159:1247-53. [PMID: 11583952 PMCID: PMC1850504 DOI: 10.1016/s0002-9440(10)62511-4] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 07/16/2001] [Indexed: 10/18/2022]
Abstract
Epidermal clones of p53-mutated keratinocytes are abundant in chronically sun-exposed skin and may play an important role in early development of skin cancer. Advanced laser capture microdissection enables genetic analysis of targeted cells from tissue sections without contamination from neighboring cells. In this study p53 gene mutations were characterized in single cells from normal, chronically sun-exposed skin. Biopsies were obtained from skin subjected to daily summer sun and skin totally protected from the sun by blue denim fabric. Using laser capture microdissection, 172 single-cell samples were retrieved from four biopsies and analyzed using single-cell polymerase chain reaction and direct DNA sequencing. A total of 14 different mutations were identified in 26 of 99 keratinocytes from which the p53 gene could be amplified. Mutations displayed a typical UV signature and were detected in both scattered keratinocytes and in a small cluster of p53-immunoreactive keratinocytes. This minute epidermal p53 clone had a diameter of 10 to 15 basal cells. Two missense mutations were found in all layers of epidermis within the p53 clone. The presented data show that p53 mutations are common in normal skin and that a clone of keratinocytes with a mutated p53 gene prevailed despite 2 months of total protection from ultraviolet light.
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Magnusson U, Pedersen Mörner A, Persson A, Karlstam E, Sternberg S, Kindahl H. Sows intramammarily inoculated with Escherichia coli influence of time of infection, hormone concentrations and leucocyte numbers on development of disease. JOURNAL OF VETERINARY MEDICINE. B, INFECTIOUS DISEASES AND VETERINARY PUBLIC HEALTH 2001; 48:501-12. [PMID: 11666032 DOI: 10.1046/j.1439-0450.2001.00469.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The aim of this study was to identify factors that influence the development of disease in sows inoculated with Escherichia coli in the mammary gland. Ten cross-bred primiparous sows were intramammarily inoculated with living E. coli bacteria at different time points before parturition: seven sows within 48 h before parturition and three sows approximately 96 h before parturition. Before and after inoculation, blood samples and mammary gland biopsy specimens were collected and clinical observations were made. All seven sows inoculated close to parturition developed a rectal temperature of >39.5 degrees C during the first 48 h post-partum and two of them also showed other signs of clinical disease. In the sows inoculated 4 days before parturition, the rectal temperature never exceeded 39.5 degrees C during the first 48 h post-partum and none of them showed any other sign of clinical discase. There was a tendency (P < 0.1) that histological signs of mastitis were more frequent in the sows inoculated close to parturition. There were no overall differences between the two groups of sows in plasma concentrations of cortisol, oestradiol-17beta and 15-ketodihydro-PGF2alpha before inoculation. Before inoculation, the number of neutrophils in the blood was overall higher (P < 0.05) in the group of sows that were inoculated close to parturition. In comparison, the number of lymphocytes before inoculation had a tendency (P < 0.1) to be lower in that group. The data suggest that the time of infection of the mammary gland relative to parturition and the number of circulating neutrophils at the time of infection influence the development of chinical coliform mastitis in the sow.
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Persson A. [Fading optimism when it comes to xenotransplantation. Still a long way to go before whole porcine organs can be transferred to human beings]. LAKARTIDNINGEN 2001; 98:3200-2. [PMID: 11496805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
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Hoyles L, Falsen E, Holmström G, Persson A, Sjödén B, Collins MD. Actinomyces suimastitidis sp. nov., isolated from pig mastitis. Int J Syst Evol Microbiol 2001; 51:1323-1326. [PMID: 11491328 DOI: 10.1099/00207713-51-4-1323] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
An unusual Actinomyces-like bacterium originating from a pig with mastitis was subjected to a polyphasic taxonomic investigation. The morphological and biochemical characteristics of the organism were consistent with its preliminary assignment to the genus Actinomyces but it did not appear to correspond to any recognized species. PAGE analysis of whole-cell proteins confirmed the phenotypic distinctiveness of the bacterium and 16S rRNA gene sequence analysis demonstrated that it represents a hitherto unknown sub-line amongst a cluster of Actinomyces species which embraces Actinomyces canis, Actinomyces georgiae, Actinomyces hyovaginalis, Actinomyces meyeri, Actinomyces odontolyticus, Actinomyces radingae and Actinomyces turicensis. Based on phylogenetic and phenotypic evidence, it is proposed that the unknown bacterium isolated from pig mastitis be classified as Actinomyces suimastitidis sp. nov. The type strain of Actinomyces suimastitidis is CCUG 39279T (= CIP 106779T).
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Persson A, Garde A, Jönsson AS, Jonsson G, Zacchi G. Conversion of sodium lactate to lactic acid with water-splitting electrodialysis. Appl Biochem Biotechnol 2001; 94:197-211. [PMID: 11563823 DOI: 10.1385/abab:94:3:197] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2000] [Revised: 03/01/2001] [Accepted: 03/01/2001] [Indexed: 11/11/2022]
Abstract
The conversion of sodium lactate to lactic acid with water-splitting electrodialysis was investigated. One way of reducing the power consumption is to add a conductive layer to the acid compartment. Doing this reduced the power consumption by almost 50% in a two-compartment cell, whereas the electric current efficiency was not affected at all. Three different solutions were treated in the electrodialysis unit: a model solution with 70 g/L of sodium lactate and a fermentation broth that had been prefiltered two different ways. The fermentation broth was either filtered in an open ultrafiltration membrane (cut-off of 100,000 Dalton) in order to remove the microorganisms or first filtered in the open ultrafiltration membrane and then in an ultrafiltration membrane with a cut-off of 2000 Dalton to remove most of the proteins. The concentration of sodium lactate in the fermentation broth was 70 g/L, as well. Organic molecules present in the broth (peptides and similar organic material) fouled the membranes and, therefore, increased power consumption. Power consumption increased more when permeate from the more open ultrafiltration membrane was treated in the electrodialysis unit than when permeate from the membrane with the lower cut-off was treated, since there was a higher amount of foulants in the former permeate. However, the electrodialysis membranes could be cleaned efficiently with a 0.1 M sodium hydroxide solution.
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Persson A, Jönsson AS, Zacchi G. Separation of lactic acid-producing bacteria from fermentation broth using a ceramic microfiltration membrane with constant permeate flow. Biotechnol Bioeng 2001; 72:269-77. [PMID: 11135196 DOI: 10.1002/1097-0290(20010205)72:3<269::aid-bit3>3.0.co;2-h] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The influence of several operating parameters on the critical flux in the separation of lactic acid-producing bacteria from fermentation broth was studied using a ceramic microfiltration membrane equipped with a permeate pump. The operating parameters studied were crossflow velocity over the membrane, bacterial cell concentration, protein concentration, and pH. The influence of the isoelectric point (IEP) of the membrane was also investigated. In the interval studied (5.3-10.8 m/s), the crossflow velocity had a marked effect on the critical flux. When the crossflow velocity was increased the critical flux also increased. The bacterial cells were retained by the membrane and the concentration of bacterial cells did not affect the critical flux in the interval studied (1.1-3.1 g/L). The critical flux decreased when the protein concentration was increased. It was found that the protein was adsorbed on the membrane surface and protein retention occurred even though the conditions were such that no filter cake was present on the membrane surface. When the pH of the medium was lowered from 6 to 5 (and then further to 4) the critical flux decreased from 76 L/m(2)h to zero at both pH 5 and pH 4. This was found to be due to the fact that the lowering in pH had affected the physiology of the bacterial cells so that the bacteria tended to adhere to the membrane and to each other. The critical flux, for wheat flour hydrolysate without particles, was much lower (28 L/m(2)h) when using a membrane with an IEP of 5.5 than the critical flux of a membrane with an IEP at pH 7 (96 L/m(2)h). This was found to be due to an increased affinity of the bacteria for the membrane with the lower IEP.
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97
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Rydhmer L, Johansson K, Eliasson-Selling L, Persson A. Clinical and Genetic Studies of Disturbed Milk Production in Sows. ACTA AGR SCAND A-AN 2001. [DOI: 10.1080/090647001300004736] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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98
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Graffner-Nordberg M, Marelius J, Ohlsson S, Persson A, Swedberg G, Andersson P, Andersson SE, Aqvist J, Hallberg A. Computational predictions of binding affinities to dihydrofolate reductase: synthesis and biological evaluation of methotrexate analogues. J Med Chem 2000; 43:3852-61. [PMID: 11052790 DOI: 10.1021/jm0009639] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The relative binding affinities to human dihydrofolate reductase of four new potential antifolates, containing ester linkages between the two aromatic systems, were estimated by free energy perturbation simulations. The ester analogue, predicted to exhibit the highest binding affinity to human dihydrofolate reductase, and a reference ester (more structurally related to methotrexate) were synthesized. As deduced from the measured IC(50) values, the calculated ranking of the ligands was correct although a greater difference in affinity was indicated by the experimental measurements. Among the new antifolates the most potent inhibitor exhibited a similar pharmacokinetic profile to methotrexate but lacked activity in a complex antiarthritic model in rat in vivo.
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99
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Kling C, Persson A, Gardulf A. The health-related quality of life of patients suffering from the late effects of polio (post-polio). J Adv Nurs 2000; 32:164-73. [PMID: 10886448 DOI: 10.1046/j.1365-2648.2000.01412.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In Sweden alone, there are today approximately 10 000-16 500 polio survivors. Between 60% and 80% experience new symptoms several years after the initial attack of poliomyelitis. The aims of this study were to investigate and describe the self-rated health-related quality of life and functional status of a group of Swedish patients with post-polio, to investigate whether any differences within the group could be related to demographic or disease-specific data and to compare the post-polio patients with individuals sampled from the general population. Data were obtained by using two questionnaires, the Swedish Health-Related Quality of Life Questionnaire (SWED-QUAL) and the Sickness Impact Profile (SIP). A total of 150 patients, 86 women and 64 men with median age 61 (20-82) years, were consecutively included. The study showed that the patients mainly reported that their physical, functional status was affected by their post-polio condition. Factors found to be associated with the physical, functional status were age and the number of parts of the body affected by the polio. On comparing the post-polio patients with two samples from the Swedish general population, it was found that the patients reported a poorer functional status and health-related quality of life. The women with post-polio reported more pain, as compared with both the men with post-polio and the women in the general population sample. The family life of the patients - in contrast to their physical abilities - did not seem to be affected by the new deteriorating condition. It is concluded that, owing to the wide range of symptoms, the patients with post-polio need care and support from multidisciplinary teams, including nurses and occupational therapists.
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Abstract
A methodology using biosensor technology for combined kinetic and thermodynamic analysis of biomolecular interactions is described. Rate and affinity constants are determined with BIAcore. Thermodynamics parameters, changes in free energy, enthalpy and entropy, are evaluated from equilibrium data and by using rate constants and transition state theory. The methodology using van't Hoff theory gives complementary information to microcalorimetry, since only the direct binding is measured with BIAcore whereas microcalorimetry measures all components, including e.g. hydration effects. Furthermore, BIAcore gives possibilities to gain new information by thermodynamic analysis of the rate constants.
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