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T Tuomi

Publications and source records attributed to T Tuomi.

At least 37 records · Page 2Linked to original sources
PubMed2001

Prediction of silent celiac disease at diagnosis of childhood type 1 diabetes by tissue transglutaminase autoantibodies and HLA.

AIMS: The aims were to estimate the diagnostic sensitivity and specificity of autoantibodies to tissue transglutaminase (IgA- and IgG-tTG), gliadin (AGA) and endomysium (EMA) in relation to human leukocyte antigen (HLA)-DQB1 alleles to identify silent celiac disease at diagnosis of type 1 diabetes. METHODS: IgA- and IgG-tTG were measured in radioligand binding assays in 165 type 1 diabetic patients. Data on HLA-DQB1 were available for 148 patients and on both AGA and EMA for 164 patients. For patients considered positive for AGA or EMA, or both, an intestinal biopsy was suggested. HLA-DQB1 typing was carried out by polymerase chain reaction and hybridization with allele specific probes. RESULTS: Three patients, left out from further study of antibodies, but not from HLA-DQB1 analysis, had treated celiac disease at diagnosis. Out of the other 162 type 1 diabetic patients tested, nine had IgA-tTG, six IgG-tTG, eight EMA, and 11 AGA. Biopsy was suggested for nine patients, of whom six showed villous atrophy, one did not and two refused to participate. Thus, silent celiac disease was probable in 8/162 and biopsy-verified in 6/162, where five patients were AGA-positive and six either EMA-, IgA-tTG- or IgG-tTG-positive. Of the 11 patients with celiac disease (three with treated and eight with silent celiac disease), 10 were HLA-DQB1-typed, of whom 65% (13/20) had the DQB1*02 allele, compared with 36% (100/276; p = 0.011) of those without celiac disease. IgA-tTG levels were higher in patients having either *02 or *0302 (0.6; -1.3-112.4 RU) compared with those not having these alleles (0.4; -0.7-3.4 RU; p = 0.023). CONCLUSION: IgA-tTG are HLA-DQB1*02-associated autoantibodies with high sensitivity and specificity for silent celiac disease at diagnosis of type 1 diabetes.

Journal Article↗
PubMed2001

Detection of aflatoxins (G(1-2), B(1-2)), sterigmatocystin, citrinine and ochratoxin A in samples contaminated by microbes.

A method is described for the simultaneous determination of common aflatoxins (G1, G2, B1, B2) and their precursor sterigmatocystin, and also citrinine and ochratoxin A. The method was applied to a building material matrix artificially contaminated with mycotoxin-producing fungi. The method includes extraction, sample pre-treatment and reversed-phase HPLC separation with tandem mass spectrometric identification and quantification using electrospray ionisation on a quadrupole ion trap mass analyser (ESI-MS-MS). Aqueous methanol was used in the initial extraction and solvent partitioning and solid phase extraction in the purification of samples. The HPLC separation was run on-line with the ESI-MS-MS detection. The limit of quantification of the procedure was 200 ng for all compounds. Recoveries of the sample pre-treatment varied from 28 to 99%. The average compound- and concentration-dependent accuracy and precision (RSD) were 21 and 113%, respectively. The method includes small sample volumes (approximately 1 g in 20 ml) and few, non-labour intensive, sample treatment steps. It should allow for a high throughput of samples with good prospects of automation.

Aflatoxins↗
PubMed2001

Sensitisation to enzymes in the animal feed industry.

OBJECTIVES: To assess the prevalence of enzyme sensitisation in the animal feed industry. METHODS: A cross sectional study was conducted in four animal feed factories, where several enzymes had been used in powder form for 7-9 years. Before this study, enzymes in liquid form had started to be used. Sensitisation to enzymes was examined by skin prick and radioallergosorbent (RAST) tests. Altogether 218 workers were tested; 140 people in various tasks in manufacturing, where exposure to various organic dusts and to enzymes was possible, and 78 non-exposed office workers. The workers were interviewed for work related respiratory and skin symptoms. Total dust concentrations were measured by a gravimetric method. The concentrations of protease and alpha-amylase were measured with catalytic methods and that of xylanase with an immunological method. RESULTS: Ten workers (7%) were sensitised to enzymes in the exposed group of 140, whereas none were sensitised in the non-exposed group. Six of the sensitised people had respiratory symptoms at work: two of them especially in connection with exposure to enzymes. Enzyme concentrations in the air varied greatly: xylanase from less than 0.8 ng/m(3) up to 16 ng/m(3), alpha-amylase from less than 20 ng/m(3) up to 200 ng/m(3), and protease from less than 0.4 ng/m(3)up to 2900 ng/m(3). On average, highest xylanase and alpha-amylase concentrations were found in the various manufacturing sites, whereas the highest protease concentrations were found in areas of high total dust. CONCLUSIONS: Industrial enzymes may cause allergies in the animal feed industry. There is a need to assess exposure to enzymes at various phases of production, and to minimise exposures.

Adult↗
PubMed2001

Possible human leukocyte antigen-mediated genetic interaction between type 1 and type 2 Diabetes.

We assessed the prevalence of families with both type 1 and type 2 diabetes in Finland; and we studied, in patients with type 2 diabetes, the association between a family history of type 1 diabetes, glutamic acid decarboxylase (GAD) antibodies (GADab), and type 1 diabetes-associated human leukocyte antigen (HLA) DQB1-genotypes. Further, in mixed type 1/type 2 diabetes families, we investigated whether sharing an HLA haplotype with a family member with type 1 diabetes influenced the manifestation of type 2 diabetes. Among 695 families ascertained through the presence of more than 1 patient with type 2 diabetes, 100 (14%) also had members with type 1 diabetes. Type 2 diabetic patients from the mixed families had, more often, GADab (18% vs. 8%, P < 0.0001) and DQB1*0302/X genotype (25% vs. 12%, P = 0.005) than patients from families with only type 2 diabetes; but they had a lower frequency of DQB1*02/0302 genotype, compared with adult-onset type 1 patients (4% vs. 27%, P < 0.0001). In the mixed families, the insulin response to oral glucose load was impaired in patients who had HLA class II risk haplotypes, either DR3(17)-DQA1*0501-DQB1*02 or DR4*0401/4-DQA1*0301-DQB1*0302, compared with patients without such haplotypes (P = 0.016). This finding was independent of the presence of GADab. We conclude that type 1 and type 2 diabetes cluster in the same families. A shared genetic background with a patient with type 1 diabetes predisposes type 2 diabetic patients both to autoantibody positivity and, irrespective of antibody positivity, to impaired insulin secretion. The findings support a possible genetic interaction between type 1 and type 2 diabetes mediated by the HLA locus.

Autoantibodies↗
PubMed2001

Fiber fractions from processing of barley in production and conservation of a biologic control agent.

Carriers are frequently used to overcome problems associated with microbial survival in soil after inoculation. Moreover, the use of carriers can prolong the shelf lives and lessen dusting of both biofungicides and biologic fertilizers. This study investigated the suitability of barley-based fiber fractions as growth media and immobilization matrices in the cultivation of a Streptomyces griseoviridis biologic control agent, as well as for the conservation of obtained biomass in dehydrated hydrogel capsules. The second main ingredient in all the examined carrier matrices was alginate. The aim was to find a hydrogel formulation suited for a production process in which all individual steps, including cultivation of the organism; downstream processing; and formulation, storage, and application of the product (i.e., biologic control agent), are carried out in the hydrogel matrix. Of the tested fractions, brewer's spent grain was the best choice, when considering the price vs the nutrient contents as well as the storage time and ease of processing of the crude and the finished products. It seems that cereal fibers can be replenished with cereal fractions less rich in fiber but having a higher content of utilizable nutrients and, hence, better suited for the production of biomass. A high content of water-insoluble fiber favorably influenced the appearance as well as the applicability of the products.

Alginates↗
PubMed2001

Cardiovascular morbidity and mortality associated with the metabolic syndrome.

OBJECTIVE: To estimate the prevalence of and the cardiovascular risk associated with the metabolic syndrome using the new definition proposed by the World Health Organization RESEARCH DESIGN AND METHODS: A total of 4,483 subjects aged 35-70 years participating in a large family study of type 2 diabetes in Finland and Sweden (the Botnia study) were included in the analysis of cardiovascular risk associated with the metabolic syndrome. In subjects who had type 2 diabetes (n = 1,697), impaired fasting glucose (IFG)/impaired glucose tolerance (IGT) (n = 798) or insulin-resistance with normal glucose tolerance (NGT) (n = 1,988), the metabolic syndrome was defined as presence of at least two of the following risk factors: obesity, hypertension, dyslipidemia, or microalbuminuria. Cardiovascular mortality was assessed in 3,606 subjects with a median follow-up of 6.9 years. RESULTS: In women and men, respectively, the metabolic syndrome was seen in 10 and 15% of subjects with NGT, 42 and 64% of those with IFG/IGT, and 78 and 84% of those with type 2 diabetes. The risk for coronary heart disease and stroke was increased threefold in subjects with the syndrome (P < 0.001). Cardiovascular mortality was markedly increased in subjects with the metabolic syndrome (12.0 vs. 2.2%, P < 0.001). Of the individual components of the metabolic syndrome, microalbuminuria conferred the strongest risk of cardiovascular death (RR 2.80; P = 0.002). CONCLUSIONS: The WHO definition of the metabolic syndrome identifies subjects with increased cardiovascular morbidity and mortality and offers a tool for comparison of results from diferent studies.

Adult↗
PubMed2000

Pulmonary mineral fibers after occupational and environmental exposure to asbestos in the Russian chrysotile industry.

BACKGROUND: As an indicator of occupational, domestic, and environmental exposure, the level and type of asbestos fibers were determined from lung tissue samples of workers and residents who resided in the area of the world's largest asbestos mine at Asbest, Russia. METHODS: Electron microscopy was used to analyze and measure the concentration of asbestos fibers in a series of 47 autopsies at the Asbest Town Hospital. Work histories were obtained from pathology reports and employment records. RESULTS: In 24 chrysotile miners, millers, and product manufacturers, the pulmonary concentrations of retained fibers (over 1 microm in length) were 0. 8-50.6 million f/g for chrysotile, and < 0.1-1.9 million f/g for amphiboles (tremolite and anthophyllite). The concentrations were lower in 23 persons without any known occupational contact with asbestos; 0.1-14.6 million f/g for chrysotile, and < 0.1-0.7 million f/g for amphiboles. On average, 90% of all inorganic fibers were chrysotile, and 5% tremolite/anthophyllite. No amosite or crocidolite fibers were detected in any of the samples. CONCLUSIONS: The mean and range of pulmonary chrysotile concentrations were about the same as reported previously from the Canadian mining and milling industry. In the Russian samples, the mean concentration of tremolite fibers were less by at least one order of magnitude. Occupational contact was the most important source of asbestos exposure.

Adolescent↗
PubMed2000

Insulin secretion and insulin sensitivity in diabetic subgroups: studies in the prediabetic and diabetic state.

AIMS/HYPOTHESIS: To evaluate insulin sensitivity and insulin secretion in prediabetic and diabetic subjects with mutations in MODY1 (HNF-4 alpha) and MODY3 (HNF-1 alpha) genes, in subjects with GAD antibodies, latent autoimmune diabetes in adults and in subjects with the common form of Type II (non-insulin-dependent) diabetes mellitus. METHODS: Insulin secretion was measured as the incremental 30-min insulin (I30) and insulin glucose ratio (I:G30) during OGTT whereas insulin sensitivity was measured as the insulin sensitivity index during OGTT in 131 carriers of MODY mutations [NGT = 38, IFG/IGT = 21, diabetes mellitus (DM) = 72], in 293 subjects with GADA (NGT = 47, IFG/IGT = 29, DM = 217) and in 2961 subjects with a family history of the common form of Type II diabetes but without MODY mutations or GADA (NGT = 1360, IFG/IGT = 857, DM = 744). A subgroup of the subjects underwent a euglycaemic clamp (n = 210) and intravenous glucose tolerance test (n = 337) for the estimation of insulin sensitivity and first-phase insulin secretion. RESULTS: Non-diabetic subjects with MODY mutations had pronounced impaired insulin secretion (I30, I:G30) compared with the two other groups (p = 0.005). Normal or non-diabetic glucose tolerance was maintained by enhanced insulin sensitivity compared with the other two groups (p < 0.05 and p < 0.005). In contrast to patients with Type II diabetes and with adult latent autoimmune diabetes, MODY patients showed only a modest deterioration in insulin sensitivity at onset of diabetes. The 2-h glucose values inversely correlated with insulin sensitivity in subjects with GADA (r = -0.447, p < 0.001) and subjects from Type II diabetic families (r = -0.426, p < 0.001), whereas no such relation was observed in subjects with MODY mutations (r = 0.151, p = NS). There were no statistically significant differences in insulin secretion or insulin sensitivity between subjects with GADA or subjects with a family history of Type II diabetes, either at the NGT or the IFG/IGT stage. CONCLUSION/INTERPRETATION: Glucose-tolerant carriers of MODY mutations are characterised by a severe impairment in insulin secretion. Enhanced insulin sensitivity is the most likely explanation for the normal glucose tolerance. Whereas subjects with positive GADA or Type II diabetes have impaired insulin sensitivity with increasing glucose concentrations, MODY mutation carriers seem to be protected from the effect of glucose toxicity.

Adult↗
PubMed2000

Occupational IgE-mediated allergy to Tribolium confusum (confused flour beetle).

BACKGROUND: We report on IgE-mediated allergy in a worker caused by Tribolium confusum (confused flour beetle). These beetles lived in the "old" flour to which he was exposed in his work. CASE REPORT: A 35-year-old, nonatopic mechanic in a rye crispbread factory developed rhinitis, conjunctivitis, and asthmatic symptoms, as well as urticaria on his wrists, lower arms, hands, neck, and face, during the maintenance and repair of machines contaminated by flour. This flour had been in and on the machines for a long time, and it contained small beetles. The patient did not suffer any symptoms when handling fresh, clean flour. RESULTS: Skin prick tests with standard environmental allergens, storage mites, enzymes, flours, and molds were negative. A prick test with flour from the machines gave a 10-mm reaction. An open application of the same flour caused urticarial whealing on the exposed skin. Prick tests with fresh flour from the factory were negative. A prick test with minced T. confusum from the flour in the machines gave a 7-mm reaction. Histamine hydrochloride 10 mg/ml gave a 7-mm reaction. Specific serum IgE antibodies to T. confusum were elevated at 17.2 kU/l. Prick tests with the flour from the machines were negative in five control patients. CONCLUSIONS: The patient had occupational contact urticaria, rhinitis, conjunctivitis, and asthmatic symptoms from exposure to flour. His symptoms were caused by immediate allergy to the beetle T. confusum. Immediate allergy to this beetle has rarely been reported in connection with respiratory symptoms, but it may be more common. Contact urticaria from this source has not been reported before.

Adult↗
PubMed2000

The common PPARgamma Pro12Ala polymorphism is associated with decreased risk of type 2 diabetes.

Genetic association studies are viewed as problematic and plagued by irreproducibility. Many associations have been reported for type 2 diabetes, but none have been confirmed in multiple samples and with comprehensive controls. We evaluated 16 published genetic associations to type 2 diabetes and related sub-phenotypes using a family-based design to control for population stratification, and replication samples to increase power. We were able to confirm only one association, that of the common Pro12Ala polymorphism in peroxisome proliferator-activated receptor-gamma(PPARgamma) with type 2 diabetes. By analysing over 3,000 individuals, we found a modest (1.25-fold) but significant (P=0.002) increase in diabetes risk associated with the more common proline allele (85% frequency). Moreover, our results resolve a controversy about common variation in PPARgamma. An initial study found a threefold effect, but four of five subsequent publications failed to confirm the association. All six studies are consistent with the odds ratio we describe. The data implicate inherited variation in PPARgamma in the pathogenesis of type 2 diabetes. Because the risk allele occurs at such high frequency, its modest effect translates into a large population attributable risk-influencing as much as 25% of type 2 diabetes in the general population.

Adult↗
PubMed2000

Autoimmunity to glutamic acid decarboxylase in patients with autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED).

Antibodies to glutamic acid decarboxylase (GAD) occur frequently in patients with APECED, although clinical insulin-dependent diabetes mellitus (IDDM) is seen only in a subgroup of the patients. We studied the cellular immunity to GAD, antibodies to GAD and their association with the HLA DQB1 risk alleles for IDDM in patients with APECED. Proliferation responses to GAD were enhanced in the patients with APECED when compared with the control subjects (P = 0.004), but autoimmunity to GAD was not associated with IDDM in APECED. The levels of interferon-gamma (IFN-gamma) secreted by GAD-stimulated T cells were higher in the patients than in control subjects (P = 0. 001). A negative correlation (r = - 0.436, P = 0.03) existed between the antibody levels and the stimulation indices (SIs) to GAD. In 14 non-diabetic patients no difference in insulin secretion was observed in intravenous glucose tolerance test (IVGTT) between the patients with and without T cell reactivity to GAD. We conclude that cellular immunity to GAD detected as T cell proliferation response to GAD or IFN-gamma secretion by GAD-stimulated T cells was frequent in patients with APECED (69%) and was not restricted to the patients with clinically detectable beta-cell damage.

Adolescent↗
PubMed2000

Emission of ozone and organic volatiles from a selection of laser printers and photocopiers.

To estimate the impact of office equipment on the quality of indoor air, the emission of ozone and organic volatiles was measured from one photocopier and four laser printers, three of which operated according to traditional corona discharge technology. The laser printers equipped with traditional technology emitted significant amounts of ozone and formaldehyde. Lesser amounts of other volatile aldehydes were emitted during printing. The photocopier emitted mainly ozone. In a well-ventilated office environment, the amounts encountered here for individual volatiles were within recommended maximum exposure limits for a reasonable density of printers. Because it is not known whether the concentration of irritating volatiles, such as formaldehyde, should be kept lower in an ozone rich environment or not, and because emissions in the immediate vicinity of the printers exceeded recommendations, the authors recommend that laser printers equipped with the traditional corona rods not be placed beside or immediately at the working site of office personnel. This way, ozone concentrations can be kept below recommended maximum exposure limits, provided that the ventilation rate is adequate. Further, it seems that if a reliable quantitative comparison of total organic volatiles prior to and during printing is to be made, the inertness of the sorbent toward ozone should be confirmed.

Air Pollutants, Occupational↗
PubMed2000

Mycotoxins in crude building materials from water-damaged buildings.

We analyzed 79 bulk samples of moldy interior finishes from Finnish buildings with moisture problems for 17 mycotoxins, as well as for fungi that could be isolated using one medium and one set of growth conditions. We found the aflatoxin precursor, sterigmatocystin, in 24% of the samples and trichothecenes in 19% of the samples. Trichothecenes found included satratoxin G or H in five samples; diacetoxyscirpenol in five samples; and 3-acetyl-deoxynivalenol, deoxynivalenol, verrucarol, or T-2-tetraol in an additional five samples. Citrinine was found in three samples. Aspergillus versicolor was present in most sterigmatocystin-containing samples, and Stachybotrys spp. were present in the samples where satratoxins were found. In many cases, however, the presence of fungi thought to produce the mycotoxins was not correlated with the presence of the expected compounds. However, when mycotoxins were found, some toxigenic fungi usually were present, even if the species originally responsible for producing the mycotoxin was not isolated. We conclude that the identification and enumeration of fungal species present in bulk materials are important to verify the severity of mold damage but that chemical analyses are necessary if the goal is to establish the presence of mycotoxins in moldy materials.

Aspergillus↗
PubMed2000

Risk of enzyme allergy in the detergent industry.

OBJECTIVES: To assess the prevalence of enzyme sensitisation in the detergent industry. METHODS: A cross sectional study was conducted in a detergent factory. Sensitisation to enzymes was examined by skin prick and radioallergosorbent (RAST) tests. 76 Workers were tested; 40 in manufacturing, packing, and maintenance, and 36 non-exposed people in management and sales departments. The workers were interviewed for work related respiratory and skin symptoms. Total dust concentrations were measured by a gravimetric method, and the concentration of protease in air by a catalytic method. RESULTS: Nine workers (22%) were sensitised to enzymes in the exposed group of 40, whereas none were sensitised in the non-exposed group. All the sensitised people had symptoms at work; all had rhinitis and one had asthma. Protease concentrations were generally < 20 ng/m3, but occasional peak values up to 80 ng/m3 were detected in the packing and maintenance tasks, and high values of > 1 microgram/m3 in the mixing area. CONCLUSION: Despite the use of encapsulated enzyme preparations, high enzyme concentrations in workplace air are possible, resulting in a higher risk of sensitisation than expected.

Adult↗
PubMed2000

Insulin and glucagon secretion in patients with slowly progressing autoimmune diabetes (LADA).

To metabolically characterize patients with slowly progressing autoimmune diabetes (LADA) of short duration we measured insulin, C peptide, and glucagon responses to glucose and arginine at three blood glucose levels (fasting and 14 and 28 mmol/L) in 11 patients with LADA, 11 patients with type 2 diabetes, and 14 healthy control subjects matched for age and body mass index. The acute insulin response to arginine was impaired in LADA vs. type 2 diabetes at all glucose levels, with the greatest impairment in the maximally stimulated insulin concentrations (P<0.04). In contrast, beta-cell sensitivity to glucose was unaltered in LADA and type 2 diabetes. The glucagon concentrations were elevated in both LADA and type 2 diabetic patients compared with healthy control subjects (P<0.02), but did not differ between the diabetic groups. In conclusion, patients with LADA share insulin resistance with type 2 diabetic patients, but display a more severe defect in maximally stimulated beta-cell capacity than patients with type 2 diabetes.

Adult↗