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L Andersson

Publications and source records attributed to L Andersson.

At least 73 records · Page 4Linked to original sources
PubMed2001

Mapping loci causing susceptibility to anal atresia in pigs, using a resource pedigree.

BACKGROUND/PURPOSE: Very little information on the genetic background for anal atresia (anorectal malformations; AA) in humans has been described. A strikingly similar natural anomaly occurs in piglets. The authors have used this as an animal model for various research purposes. The affected piglets were treated surgically soon after birth, raised, and used for breeding. The authors have generated a resource pedigree segregating for this naturally occurring nonsyndromal AA and describe here the first attempt to map susceptibility loci by marker analysis. METHODS: A pig pedigree with a high incidence of AA has been established by selective breeding using 3 probands from the Landrace and Large White breeds. It has been maintained by intrafamilial crossing for more than 15 years. A backcross pedigree has now been generated by mating 4 AA females to an unaffected male from the Chinese Meishan breed. F(1) animals were both intercrossed and backcrossed to affected AA animals. A genome scan was carried out using the F(0), F(1), and affected backcross progeny. Ninety-two microsatellite loci were analyzed using fluorescently labelled primers and an ABI377 sequencer. Linkage analysis was done with the CRI-MAP 2.4 software. RESULTS: Crossing affected parents increased the incidence of abnormalities from 30% to 61.9%. All 39 F(1) pigs were unaffected. In the F(1) intercross, only 3 of 205 (1.5%) were affected, whereas 42 of 523 (8.0%) backcross progeny were affected. The marked difference in the incidence of affected progeny in the F(1) intercross and in the backcross indicates the presence of multiple genes causing AA. The genome scan showed suggestive evidence for the presence of a susceptibility locus on pig chromosome 15 (lod score 2.7 for a pig microsatellite marker SW2072). CONCLUSIONS: The results clearly show that AA has a oligogenic or polygenic background. The genome scan showed one suggestive locus causing AA on pig chromosome 15. The long-term goal is to identify causative genes for this malformation by comparative positional candidate cloning. This study provides, for the first time, linkage mapping of nonsyndromal anorectal malformations with a polygenic inheritance.

Animals↗
PubMed2001

Immediate or late weight bearing after uncemented total hip arthroplasty: a study of functional recovery.

Late weight bearing on the operated leg after uncemented total hip arthroplasty may slow the patient's rehabilitation. The aim of this study was to find out whether 12 weeks of non-weight-bearing gait had any influence on passive hip extension, muscle strength, gait velocity, pain, and walking pattern during the first 24 postoperative weeks. There were no significant differences in results 24 weeks after surgery between 10 patients with late weight bearing and 11 patients with immediate weight bearing. As expected, however, there was a difference in muscle strength between the operated and the nonoperated leg. This study shows no evidence that late weight bearing after uncemented total hip arthroplasty implies any serious adverse effects on functional recovery after 24 weeks compared with immediate postoperative weight bearing.

Adult↗
PubMed2001

Interdental wiring in jaw fractures: effects on teeth and surrounding tissues after a one-year follow-up.

Several authors have suggested that interdental wiring may have an adverse effect on the teeth and surrounding tissues. In the present study we examined 250 teeth that had been subjected to wiring and 142 adjacent teeth that had not been wired (controls). During the wiring period, and after a minimum of 1 year following treatment of the jaw fracture, the teeth and periodontal tissues were examined by periodontal probing, percussion sound test, mobility test, sensitivity test, and radiography. One tooth showed temporary increased mobility. Periodontal health was clinically and radiologically fully restored after a year in all teeth. Progressive caries was seen in 2 patients and was treated. Loss of sensitivity was seen in 3 teeth adjacent to the fracture site and in one tooth adjacent to a titanium cortical screw. However, these pulpal changes either recovered spontaneously or were treated endodontically. There were few late problems in the teeth and surrounding tissues. In 243 teeth (97%), completely healthy conditions were found in pulp and periodontium. There was no evidence of root resorption or dentoalveolar ankylosis. We conclude that late deleterious effects on the teeth and periodontal tissues from interdental wiring in the treatment of jaw fractures were uncommon 1 year after the removal of the interdental wiring.

Adolescent↗
PubMed2001

Procera AllCeram laminates: a clinical report.

The use of Procera AllCeram laminates for patients with discolored teeth has been described. In our experience, these laminates are simple to use and provide possibilities for excellent esthetics.

Aluminum Oxide↗
PubMed2001

Screening and scanning of single nucleotide polymorphisms in the pig melanocortin 1 receptor gene (MC1R) by pyrosequencing.

The increasing interest in the discovery and characterization of single nucleotide polymorphisms (SNPs) emphasis the need for high-throughput and cost effective scoring methods. Pyrosequencing is a novel method for screening SNPs. In this study we examine breed specific SNPs in the pig melanocortin 1 receptor gene (MC1R), some causing coat color phenotypes. A total of fifteen pigs representing eight breeds and crosses were analyzed by pyrosequencing. In addition to nine previously known SNPs, we also detected one new missense mutation by pyrosequencing. We here show that the SNPs were readily scored using standard reaction conditions. Insertions as well as substitutions were unambiguously detected and all genotypes were resolved in terms of homo- and heterozygozity.

Animals↗
PubMed2001

A frameshift mutation in MC1R and a high frequency of somatic reversions cause black spotting in pigs.

Black spotting on a red or white background in pigs is determined by the E(P) allele at the MC1R/Extension locus. A previous comparison of partial MC1R sequences revealed that E(P) shares a missense mutation (D121N) with the E(D2) allele for dominant black color. Sequence analysis of the entire coding region now reveals a second mutation in the form of a 2-bp insertion at codon 23 (nt67insCC). This mutation expands a tract of six C nucleotides to eight and introduces a premature stop codon at position 56. This frameshift mutation is expected to cause a recessive red color, which was in fact observed in some breeds with the E(P) allele present (Tamworth and Hereford). RT-PCR analyses were conducted using skin samples taken from both spotted and background areas of spotted pigs. The background red area had transcript only from the mutant nt67insCC MC1R allele, whereas the black spot also contained a transcript without the 2-bp insertion. This indicates that black spots are due to somatic reversion events that restore the frame and MC1R function. The phenotypic expression of the E(P) allele is highly variable and the associated coat color ranges from red, red with black spots, white with black spots, to almost completely solid black. In several breeds of pigs the phenotypic manifestation of this allele has been modified by selection for or against black spots.

Alleles↗
PubMed2001

Molecular phylogenetics relationship between six Chinese native pig breeds and three Swedish pig breeds from mitochondrial DNA.

Mitochondrial DNA genetic polymorphisms were used to evaluate the relationship between 6 Chinese indigenous pig breeds and 3 Swedish domestic pig breeds. A total of 440 bp of the control region and 798 bp of cytochrome b (cyt b) gene of mtDNA were determined from 140 pigs of 9 different breeds. The results of phylogenetics analysis showed that 6 Chinese native pig breeds originated from the Asian wild boar. The pairwise nucleotide sequences divergence suggested that they might occur about 413,000-875,000 years before present (YBP) between Chinese native pig breeds and European wild boar, and approximately 7,500-15,600 YBP between Chinese native pig breeds and Asian wild boar. Three Swedish pig breeds are present both European clade and Asian clade, which is due to the documented introgression of Chinese pig breeds into European domestic pig breeds 2 thousand years ago or during early 18th century.

Animals↗
PubMed2000

Lactones of methyl 3-O.

Lactones of methyl 3-O-[(R)- and (S)-1-carboxyethyl]-alpha-D-gluco-, galacto- and manno-pyranoside were prepared by treatment of the sugar derivatives in acetic acid. The lactones were formed between the 1-carboxyethyl substituent and 2-OH or 4-OH in different proportions depending on the stereochemistry of the parent compounds. Relative formation rates in acetic acid-d4 and hydrolysis rates in buffered D2O solutions at pD 2.4, 4.6 and 7.4 were estimated. Hydrolysis of the formed lactones is relatively slow in D2O at pD 4.6, which permitted characterization of the lactones by 1H and 13C NMR spectroscopy in buffered D2O solutions. Hydrolysis of the lactones in 1 M aqueous NaOH at 80 degrees C gave no detectable isomerization of the alpha-carbon. The set of lactones formed from the 1-carboxyethyl substituted methyl glycosides used in this study showed large similarities in the NMR shifts (delta delta values). Deviations from the observed shift pattern were found for two lactones. Our findings strongly suggest that those two lactones differ from the rest by adopting a boat-like conformation, whereas the others adopt pseudo-chair conformations.

Acetic Acid↗
PubMed2000

International Consultation on Urological Diseases: a decade of progress.

The International Consultation on Urological Diseases (ICUD), under the cosponsorship of the World Health Organization (WHO), the International Society of Urology (SIU), and the International Union Against Cancer (UICC), is active in the organization of global consultations on urological diseases. The major urological associations from the five continents (the American Urological Association (AUA), the Urological Association of Asia (UAA), the Confederation Americana Urologia (CAU), and the European Association of Urology (EAU)), together with societies with expertise in specific programs such as the International Continence Society, the International Society for Impotence Research, the International Prostate Health Council, the American Cancer Society, the International Union Against Cancer, and the European Organization for Research and Treatment of Cancer, came together in the late 1980s on the basis of their proven record in organizing successful international meetings on urological cancer to initiate the concept of the ICUD. At the suggestion of the WHO, a First International Consultation on Benign Prostatic Hypertrophy (BPH) was organized in 1991, not only to provide recommendations to medical practitioners but also to define and plan future research on the subject. The formula, based on global multiprofessional collaboration and expertise, exceeded expectations, and other consultations were to follow, e.g., on prostate cancer, incontinence, erectile dysfunctions, and nosocomial infections. In 1994 it became necessary to establish a legal nongovernmental organization to foster the goals of the ICUD, essentially for the creation of awareness, knowledge, and recommendations on the diagnosis and treatment of urological diseases.

Humans↗
PubMed2000

A mutation in PRKAG3 associated with excess glycogen content in pig skeletal muscle.

A high proportion of purebred Hampshire pigs carries the dominant RN- mutation, which causes high glycogen content in skeletal muscle. The mutation has beneficial effects on meat content but detrimental effects on processing yield. Here, it is shown that the mutation is a nonconservative substitution (R200Q) in the PRKAG3 gene, which encodes a muscle-specific isoform of the regulatory gamma subunit of adenosine monophosphate-activated protein kinase (AMPK). Loss-of-function mutations in the homologous gene in yeast (SNF4) cause defects in glucose metabolism, including glycogen storage. Further analysis of the PRKAG3 signaling pathway may provide insights into muscle physiology as well as the pathogenesis of noninsulin-dependent diabetes mellitus in humans, a metabolic disorder associated with impaired glycogen synthesis.

AMP-Activated Protein Kinases↗
PubMed2000

Assessment of regional cerebral blood flow by dynamic susceptibility contrast MRI using different deconvolution techniques.

Regional cerebral blood flow (rCBF) was assessed using dynamic susceptibility-contrast MRI at 1.5 T. A simultaneous dual FLASH pulse sequence and Gd-DTPA-BMA (0.3 mmol/kg b.w.) were used for examination of 43 volunteers, measuring rCBF in frontal white matter (WM) and in gray matter in the thalamus (GM). Arterial input functions (AIFs) were registered 1) in the carotid artery and 2) in an artery within the GM/WM slice. The measured concentration-vs. -time curve was deconvolved with the AIF using both Fourier Transform (FT) and Singular Value Decomposition (SVD). Relative rCBF was given by the height of the deconvolved response curve. For each volunteer, eight different rCBF maps were calculated, representing different combinations of deconvolution techniques, AIFs, and filters. The average GM-WM rCBF ratios ranged from 2.0-2.2, depending on methodology. Absolute rCBF was 68 +/- 28 ml/(min 100 g) in GM and 35 +/- 13 ml/(min 100g) in WM (mean +/- SD, n = 39). GM-WM rCBF ratios obtained using SVD were 6-10% higher than corresponding ratios obtained using FT.

Adult↗
PubMed2000

Large-scale synthesis of peptides.

Recent advances in the areas of formulation and delivery have rekindled the interest of the pharmaceutical community in peptides as drug candidates, which, in turn, has provided a challenge to the peptide industry to develop efficient methods for the manufacture of relatively complex peptides on scales of up to metric tons per year. This article focuses on chemical synthesis approaches for peptides, and presents an overview of the methods available and in use currently, together with a discussion of scale-up strategies. Examples of the different methods are discussed, together with solutions to some specific problems encountered during scale-up development. Finally, an overview is presented of issues common to all manufacturing methods, i.e., methods used for the large-scale purification and isolation of final bulk products and regulatory considerations to be addressed during scale-up of processes to commercial levels.

Amino Acids↗
PubMed2000

Proliferation and apoptosis in the evolution of endemic and acquired immunodeficiency syndrome-related Kaposi's sarcoma.

Kaposi's sarcoma (KS) is a multifocal lesion that occurs predominantly in the skin, most frequently in people infected with HIV-1, and that evolves through early stages (patch and plaque) to a tumor-like late stage (nodular). Both, endemic African (EKS) and AIDS-associated (AKS) KS expressed human herpesvirus 8 (HHV-8) as shown by PCR. By immunohistochemistry the expression of cellular Bcl-2 and c-myc was confined in early stages of both EKS and AKS to relatively few endothelial cells (EC) whereas in nodular KS most of spindle cells (SC) strongly expressed both genes. CD40 was usually strongly expressed in SC at all KS stages as well as in EC of non-involved tissue whereas CD40L (CD154) was not demonstrable. Fas (CD95) was moderately to weakly expressed by SC whereas p53 and Waf-1 were found in less than 5% of the SC. In both AKS and EKS at nodular stage almost no apoptotic SC were detected. In most AKS and EKS low levels of cell proliferation were seen but AKS showed consistently higher values compared to EKS. All clinical types and stages of KS showed a diploid cellular DNA content by flow cytometric analysis of microselected lesions. Thus, we conclude that KS during evolution represents diploid, probably reactive, cell proliferation, which progressively increases the expression of strong cellular and also viral (HHV-8) antiapoptotic factors.

Acquired Immunodeficiency Syndrome↗
PubMed2000

Referring physicians' satisfaction with the rapid response radiotherapy programme. Survey results at the Toronto-Sunnybrook Regional Cancer Centre.

For patients with advanced incurable cancer, radiotherapy provides effective palliation and improved quality of life. At the Toronto-Sunnybrook Regional Cancer Centre, the Rapid Response Radiotherapy Programme, a pilot programme in Ontario, was started in 1996 to provide timely palliative radiotherapy. Over 200 patients have been seen annually since 1996. Of the patients referred to the clinic, 90% were treated by palliative radiotherapy. Of those requiring radiotherapy, 80% received treatment on the day of their initial visits, and 90% of the irradiated patients received one to five treatments. The programme has been warmly welcomed by many community medical oncologists and palliative care consultants. Other centres in Canada have followed our example and set up similar clinics. We sent out a survey to all referring physicians to explore the strengths and weaknesses of our programme so as to improve our services. There has been an increase in the utilization of palliative radiotherapy because of the availability of our programme. As a result of this survey we corrected some of our deficiencies. We plan to survey our patients' needs and satisfaction to further improve our programme, since the patients are the ultimate consumers of the service.

Adult↗