PubMed Health⌕ Search

Biomedical subjects

S Laaksonen

Publications and source records attributed to S Laaksonen.

6 recordsLinked to original sources
PubMed2006

Molecular characterization of Echinococcus isolates of cervid origin from Finland and Sweden.

The species Echinococcus granulosus is made up of several genotypic strain groups, whose taxonomical classification is still undetermined. Genotypes in the cervid-wolf life-cycle are poorly known, especially in Europe. In this study, 33 Echinococcus isolates from cervids from Finland and Sweden were characterized using mitochondrial ND1 gene sequencing. In addition, phylogenetic analysis of E. granulosus strains using the mitochondrial ATP6, ND1, ND3 and CO1 genes was performed using maximum likelihood, neighbour-joining and maximum parsimony methods. The Finnish and Swedish cervid isolates were found to represent the genotype G10. In the phylogenetic analyses, the camel (G6), pig (G7), cervid (G8) and Fennoscandian cervid (G10) strains clustered in a well-supported monophyletic group. This group differed clearly from the common sheep (G1) and horse (G4, 'E. equinus') strains, but was closely related to the cattle strain (G5, 'E. ortleppi'). Our results support the previous studies suggesting that the genotypes G6-10 should be separated from the species E. granulosus sensu stricto. However, additional morphological studies are needed, and the relationship to the cattle strain ('E. ortleppi') should be thoroughly evaluated before a final decision of the taxonomical status of the G6-10 group can be made.

Animals↗
PubMed2005

Thalidomide therapy and polyneuropathy in myeloma patients.

Thalidomide is today an increasingly used therapy in advanced and refractory myeloma patients, especially in patients relapsing after high dose therapy. One important and well-known side effect of thalidomide is polyneuropathy (PNP). The purpose of this study was to investigate 1) how severe the thalidomide-induced PNP is in patients treated for myeloma 2) which neurophysiological tests and parameters are most sensitive in detecting the thalidomide-induced PNP and 3) how neuropathic symptoms correlate with neurophysiological changes. Twelve patients received thalidomide for treatment of relapsed multiple myeloma for at least 5 months. Prior to the thalidomide treatment, all patients had been treated with chemotherapy including vincristine, and seven patients had also received cisplatin. PNP symptoms, clinical findings and neurophysiological tests before and after the therapy were evaluated. Prior to thalidomide treatment, 7 patients had minimal and one patient slight PNP. After thalidomide treatment, 4 patients had minimal, 4 patients slight, and 3 patients moderate PNP. Thalidomide-induced PNP mainly affected sensory myelinated axons, but also alpha motor neuron axons were affected to some extent. Thermal thresholds were not altered, indicating that thin myelinated and unmyelinated axons are spared. The most sensitive parameter for detecting thalidomide-induced PNP was the sensory nerve compound action potential amplitude. The neuropathic symptoms deteriorated significantly during the therapy, but clinically, no patient developed a disabling PNP that would have required interrupting the therapy. The neuropathic side effects of thalidomide seem to be acceptable in myeloma patients.

Action Potentials↗
PubMed2001

Treating missing data in a clinical neuropsychological dataset--data imputation.

Missing data frequently reduce the applicability of clinically collected data in research requiring multivariate statistics. In data imputation, missing values are replaced by predicted values obtained from models based on auxiliary information. Our aim was to complete a clinical child neuropsychological data set containing 5.2% of missing observations. This was to be used in research requiring multivariate statistics. We compared four data imputation methods by artificially deleting some data. A real-donor imputation method which preserved the parameter estimates and which predicted the observed values with acceptable accuracy was used to complete the data set. In addressing the lack of studies with regard to treatment of missing data in neuropsychological data sets, this study presents information on the outcomes of applying data imputation methods to such data. The imputation modeling described can be applied to a variety of clinical neuropsychological data sets.

Child↗
PubMed2000

Does dialysis therapy improve autonomic and peripheral nervous system abnormalities in chronic uraemia?

OBJECTIVES: Autonomic nervous system (ANS) dysfunction and peripheral neuropathy occur in patients with chronic renal insufficiency. Adequate renal replacement therapy should prevent development or correct these abnormalities. DESIGN AND SUBJECTS: We studied retrospectively ANS and peripheral neuropathy in 32 patients with chronic uraemia who received either haemodialysis (16) or peritoneal dialysis (16) therapy, and compared the observed dialysis efficiency with changes in neurological function. METHODS: Heart rate variability (HRV) time domain indices and peripheral sensory nerve conduction studies were followed for a mean of 2.9 years. The adequacy of haemodialysis (HD) efficiency was estimated by Kt/V, an index of fractional urea clearance. Adequacy of continuous ambulatory peritoneal dialysis (CAPD) was estimated on the basis of the patient's wellbeing and nutritional status as excellent, satisfactory or poor. Based on observed changes in HRV time domain measures, the observations were divided in three subgroups: improved, unchanged or deteriorated. RESULTS: The peripheral sensory nerve conduction studies were abnormal in 38% of the patients and did not change significantly during the study. Improvement in HRV time domain measures occurred in HD patients with mean Kt/V > 1.20 or in CAPD patients with satisfactory or excellent response to dialysis treatment. Values of Kt/V < 0.85 in HD patients were associated with progressive deterioration of autonomic neuropathy. Diabetic patients (n = 4) differed from others as their HRV was grossly abnormal and did not improve. CONCLUSIONS: The adequacy of haemodialysis is a predictor of improvement of cardiac autonomic nervous function in chronic uraemia. The same trend of improvement was seen also in CAPD patients.

Autonomic Nervous System Diseases↗