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1.
J Evol Biol ; 30(8): 1561-1575, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28594470

ABSTRACT

Density dependence in vital rates is a key feature affecting temporal fluctuations of natural populations. This has important implications for the rate of random genetic drift. Mating systems also greatly affect effective population sizes, but knowledge of how mating system and density regulation interact to affect random genetic drift is poor. Using theoretical models and simulations, we compare Ne in short-lived, density-dependent animal populations with different mating systems. We study the impact of a fluctuating, density-dependent sex ratio and consider both a stable and a fluctuating environment. We find a negative relationship between annual Ne /N and adult population size N due to density dependence, suggesting that loss of genetic variation is reduced at small densities. The magnitude of this decrease was affected by mating system and life history. A male-biased, density-dependent sex ratio reduces the rate of genetic drift compared to an equal, density-independent sex ratio, but a stochastic change towards male bias reduces the Ne /N ratio. Environmental stochasticity amplifies temporal fluctuations in population size and is thus vital to consider in estimation of effective population sizes over longer time periods. Our results on the reduced loss of genetic variation at small densities, particularly in polygamous populations, indicate that density regulation may facilitate adaptive evolution at small population sizes.


Subject(s)
Genetic Drift , Reproduction , Animals , Environment , Female , Male , Population Density , Population Dynamics , Sex Ratio
2.
Regul Toxicol Pharmacol ; 74: 64-74, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26617408

ABSTRACT

Six pigment-grade (pg) or ultrafine (uf)/nanoscale (anatase and/or rutile) titanium dioxide (TiO2) particulates were evaluated for in vivo genotoxicity (OECD 474 Guidelines) in male and female rats by two different laboratories. All test materials were robustly characterized. The BET surface areas of the pg and uf samples ranged from 7 to 17 m(2)/g and 50 to 82 m(2)/g respectively. The materials were assessed for induction of micronuclei and toxicity in bone marrow by analyzing peripheral blood reticulocytes (RETs) by flow cytometry. Single oral gavage doses of 500, 1000 or 2000 mg/kg body weight (bw) of each material were implemented with concurrent negative (water) and positive controls (cyclophosphamide). Approximately 48 and 72 h after exposure, blood samples were collected and 20,000 RETs per animal were analyzed. For each of the six tests, there were no biologically or toxicologically relevant increases in the micronucleated RET frequency in any TiO2 exposed group at either time point at any dose level. In addition, there were a lack of biologically relevant decreases in %RETs among total erythrocytes. All six TiO2 test substances were negative for in vivo genotoxicity effects; however, it is noted that the exposure to target tissues was likely negligible. One pigment grade and one ultrafine material each were evaluated for potential systemic exposure/uptake from the gastrointestinal tract by analysis of TiO2 into blood and liver. No significant increases in TiO2 over controls were measured in blood (48 or 72 h) or liver (72 h) following exposures to 2000 mg/kg bw TiO2. These data indicate that there was no absorption of the test material from the gastrointestinal tract into the blood circulation and the lack of genotoxic effects is therefore attributed to a lack of exposure due to the inability of the test material to migrate from the gastrointestinal tract into the blood and then into target tissues.


Subject(s)
Micronuclei, Chromosome-Defective/chemically induced , Micronucleus Tests , Reticulocytes/drug effects , Titanium/toxicity , Administration, Oral , Animals , Female , Gastrointestinal Absorption , Male , Metal Nanoparticles , Particle Size , Rats, Sprague-Dawley , Reticulocytes/pathology , Risk Assessment , Surface Properties , Titanium/administration & dosage , Titanium/blood , Titanium/pharmacokinetics
3.
J Clin Immunol ; 33(8): 1341-8, 2013 Nov.
Article in English | MEDLINE | ID: mdl-24158785

ABSTRACT

PURPOSE: Almost all patients with autoimmune polyendocrine syndrome (APS)-I have high titer neutralizing autoantibodies to type I interferons (IFN), especially IFN-ω and IFN-α2, whatever their clinical features and onset-ages. About 90 % also have antibodies to interleukin (IL)-17A, IL-17F and/or IL-22; they correlate with the chronic mucocutaneous candidiasis (CMC) that affects ~90 % of patients. Our aim was to explore how early the manifestations and endocrine and cytokine autoantibodies appear in young APS-I patients. That may hold clues to very early events in the autoimmunization process in these patients. METHODS: Clinical investigations and autoantibody measurements in 13 APS-I patients sampled before age 7 years, and 3 pre-symptomatic siblings with AIRE-mutations in both alleles. RESULTS: Antibody titers were already high against IFN-α2 and IFN-ω at age 6 months in one sibling-8 months before onset of APS-I-and also against IL-22 at 7 months in another (still unaffected at age 5 years). In 12 of the 13 APS-I patients, antibody levels were high against IFN-ω and/or IL-22 when first tested, but only modestly positive against IFN-ω in one patient who had only hypo-parathyroidism. Endocrine organ-specific antibodies were present at age 6 months in one sibling, and as early as 36 and 48 months in two of the six informative subjects. CONCLUSION: This is the first study to collate the onset of clinical features, cytokine and endocrine autoantibodies in APS-I infants and siblings. The highly restricted early autoantibody responses and clinical features they show are not easily explained by mere loss of broad-specific self-tolerance inducing mechanisms, but hint at some more sharply focused early event(s) in autoimmunization.


Subject(s)
Autoantibodies/blood , Cytokines/immunology , Polyendocrinopathies, Autoimmune/diagnosis , Polyendocrinopathies, Autoimmune/immunology , Adolescent , Adult , Autoantibodies/biosynthesis , Child , Child, Preschool , Early Diagnosis , Female , Humans , Infant , Interferon-alpha/immunology , Interleukin-17/immunology , Interleukins/immunology , Male , Polyendocrinopathies, Autoimmune/metabolism , Syndrome , Young Adult , Interleukin-22
4.
Clin Lymphoma Myeloma Leuk ; 21(9): 598-605, 2021 09.
Article in English | MEDLINE | ID: mdl-34158268

ABSTRACT

Anti-thymocyte globulin (ATG) is commonly used to prevent graft-versus-host disease (GvHD) after allogeneic hematopoietic stem cell transplantation (allo-HSCT). To evaluate the impact of ATG as part of the GvHD prophylaxis in our institution, we report the outcome of 415 patients with matched unrelated donors (MUD) transplanted for hematological malignancies with or without ATG from 2005 to 2019 at Oslo University Hospital, Norway. The following groups were compared: (1) 154 patients transplanted with peripheral blood stem cells (PBSC) without ATG 2005-2014. (2) 137 patients transplanted with bone marrow stem cells (BMSC) 2005-2019. (3) 124 patients transplanted with PBSC and ATG (PBSC + ATG) 2014-2019. Three years survival was similar in the groups, 61% following allografting with PBSC, 54% with BMSC, and 59% with PBSC + ATG. Acute GvHD grade III-IV was 14%, 14%, and 7%; chronic GvHD was 81%, 32, and 26%; and extensive cGvHD 44%, 15%, and 6% in the corresponding groups. Both acute and chronic GvHD were significantly reduced in the PBSC + ATG-versus the PBSC group (p < 0.05 and p < 0.001 respectively).Transplant-related mortality (TRM) was 33%, 25%, and 17% (p = 0.18). Graft versus host disease and relapse free survival (GRFS) at 3 years was 43 %, 43%, and 64% in the groups. Adding ATG to the GvHD prophylaxis regimen of MUD allo-HSCT with PBSC resulted in a substantial reduction of both acute and chronic GvHD without compromising the disease control, reflected in a superior 3 years GRFS.


Subject(s)
Antilymphocyte Serum/metabolism , Hematopoietic Stem Cell Transplantation/methods , Peripheral Blood Stem Cells/metabolism , Transplantation Conditioning/methods , Transplantation, Homologous/methods , Adult , Disease-Free Survival , Female , Graft vs Host Disease , Hematopoietic Stem Cell Transplantation/mortality , Humans , Male , Middle Aged , Neoplasm Recurrence, Local , Retrospective Studies , Transplantation Conditioning/mortality , Transplantation, Homologous/mortality , Unrelated Donors
5.
Clin Hematol Int ; 2(2): 74-81, 2020 Jun.
Article in English | MEDLINE | ID: mdl-34595446

ABSTRACT

The effect of CD34+ cell dose in allogeneic hematopoietic stem cell transplantation (HSCT) on overall survival (OS) and incidence of acute and chronic graft-versus-host disease (GvHD) has not been established and few studies have been performed. Our single center analysis included 189 patients with hematological malignancies who received peripheral blood stem cell (PBSC) grafts from sibling donors. Myeloablative conditioning was used in 88 cases and 101 received reduced intensity conditioning. The median CD34+ cell dose was 5.6 × 106/kg (0.6-17.0). In the multivariate analysis, a CD34 cell dose of 6-7 × 106/kg was associated with better OS and lower transplant-related mortality (TRM), while a dose of <5 × 106/kg led to increased relapse and reduced chronic GVHD (cGVHD). A high CD34 cell-dose (>6.5 × 106/kg) correlated with less acute GVHD (aGVHD) II-IV. We conclude that the CD34 cell dose has an impact on the outcome of HSCT from sibling donor PBSCs.

6.
Article in English | MEDLINE | ID: mdl-31889957

ABSTRACT

BACKGROUND: Low bone mineral density and an increased risk of appendicular and vertebral fractures are well-established consequences of Duchenne muscular dystrophy (DMD) and the risk of fractures is exacerbated by long-term glucocorticoid treatment. Monitoring of endocrine and skeletal health and timely intervention in at-risk patients is important in the management of children with DMD. METHODS: As part of the Norwegian Duchenne muscular dystrophy cohort study, we examined the skeletal maturation of 62 boys less than 18 years old, both currently glucocorticoid treated (n = 44), previously treated (n = 6) and naïve (n = 12). The relationship between bone age, height and bone mineral density (BMD) Z-scores was explored. RESULTS: The participants in the glucocorticoid treated group were short in stature and puberty was delayed. Bone age was significantly delayed, and the delay increased with age and duration of treatment. The difference in height between glucocorticoid treated and naïve boys was no longer significant when height was corrected for delayed skeletal maturation. Mean BMD Z-scores fell below - 2 before 12 years of age in the glucocorticoid treated group, with scores significantly correlated with age, duration of treatment and pubertal development. When BMD Z-scores were corrected for by retarded bone age, the increase in BMD Z-scores was significant for all age groups. CONCLUSION: Our results suggest that skeletal maturation should be assessed in the evaluation of short stature and bone health in GC treated boys with DMD, as failing to consider delayed bone age leads to underestimation of BMD Z-scores and potentially overestimation of fracture risk.

7.
Food Chem Toxicol ; 134: 110818, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31533061

ABSTRACT

3-Fucosyllactose (3-FL), a highly abundant complex carbohydrate in human breast milk, functions as a prebiotic promoting early microbial colonization of the gut, increasing pathogen resistance and modulating immune responses. To investigate potential health benefits, 3-FL was produced by fermentation using a genetically modified E. coli K12 strain. The safety assessment of 3-FL included acute oral toxicity, in vitro and in vivo assessment of genetic toxicity, and a subchronic rodent feeding study. 3-FL was not acutely toxic at 5000 mg/kg bw, and there was no evidence of genetic toxicity in the bacterial reverse mutation test and chromosomal aberration assay. There was a repeatable statistically-significant trend in the 4-h S9-activated test conditions in the in vitro micronucleus assay; the confirmatory in vivo mouse micronucleus study was negative at all doses. Dietary subchronic exposure of rats to 3-FL (5% and 10%) did not produce any statistical or biologically-relevant differences in growth, food intake or efficiency, clinical observations, or clinical or anatomic pathology changes at average daily intakes of 5.98 and 7.27 g/kg bw/day for males and females, respectively. The weight of evidence from these studies support the safe use of 3-FL produced using biotechnology as a nutritional ingredient in foods.


Subject(s)
Biotechnology , Milk, Human/chemistry , Oligosaccharides/pharmacology , Animals , CHO Cells , Cricetulus , Dose-Response Relationship, Drug , Humans , Mutagenicity Tests , No-Observed-Adverse-Effect Level , Oligosaccharides/chemical synthesis , Oligosaccharides/toxicity , Rats
8.
Curr Med Res Opin ; 33(4): 741-748, 2017 04.
Article in English | MEDLINE | ID: mdl-28161985

ABSTRACT

BACKGROUND: The painDETECT questionnaire (PD-Q) has been used widely for the identification of neuropathic pain (NeP); however, the reliability of the English version of the PD-Q has never been investigated. OBJECTIVE: This study aimed to determine the reliability of the PD-Q pre- (T0) and immediately post- (T1) clinical consultation and at one-week follow-up (T2). METHODS: We recruited 157 patients attending a Neurosurgery Spinal Clinic and Pain Management Department. Minor changes to PD-Q instructions were made to facilitate patient understanding; however, no changes to individual items or scoring were made. Intraclass correlation coefficients (ICCs) were used to assess the reliability of PD-Q total scores between T0-T1 and T0-T2; weighted kappa (κ) was used to assess the agreement of PD-Q classifications (unlikely NeP, ambiguous, likely NeP) between all time-points. To ensure stability of clinical pain, patients scoring ≤2 or ≥6 on the Patient Global Impression Scale (PGIC) at T2 were excluded from the T0-T2 analysis. RESULTS: Accounting for missing data and exclusions (change in PGIC score), data for 136 individuals (mean [SD] age: 56.8 [15.2]; 54% male) was available, of whom n = 129 were included in the T0-T1 and n = 69 in the T0-T2 comparisons. There was almost perfect agreement between the PD-Q total scores at T0-T1 time-points (ICC 0.911; 95% CI: 0.882-0.941) and substantial agreement at T0-T2 (ICC 0.792; 95% CI: 0.703-0.880). PD-Q classifications demonstrated substantial agreement for T0-T1 (weighted κ: 0.771; 95% CI: 0.683-0.858) and for T0-T2 (weighted κ: 0.691; 95% CI: 0.553-0.830). Missing data was accounted in 13% of our cohort and over 42% of our patients drew multiple pain areas on the PD-Q body chart. CONCLUSION: The English version of the PD-Q is reliable as a screening tool for NeP. The validity of the questionnaire is still in question and has to be investigated in future studies.


Subject(s)
Neuralgia/diagnosis , Pain Measurement , Surveys and Questionnaires , Translations , Adult , Aged , Australia/epidemiology , Cross-Sectional Studies , Female , Humans , Male , Mass Screening/methods , Middle Aged , Pain Measurement/methods , Pain Measurement/standards , Quality Improvement , Reproducibility of Results
9.
Clin Chim Acta ; 359(1-2): 171-8, 2005 Sep.
Article in English | MEDLINE | ID: mdl-15936009

ABSTRACT

BACKGROUND: Subjects with familial hypercholesterolemia (FH) are associated with increased risk of premature atherosclerosis and coronary artery disease (CAD). However, onset of clinically manifested CAD varies widely among subjects with heterozygous FH. The purpose of this study was to investigate whether FH subjects with an identical mutation in the low-density lipoprotein (LDL) receptor gene have a high-density lipoprotein (HDL)3 that is characterized by a less atheroprotective functions than that of healthy controls and within subgroups of FH. DESIGN: Twenty-two adults <75 years of age with FH and 17 healthy sex- and age-matched controls were included. HDL3 was isolated and the composition was characterized from each subject, and its ability to suppress tumor necrosis factor(TNF)-alpha stimulated expression of ICAM-1 on HUVEC was investigated. In addition, plasma level of soluble sICAM-1 and VCAM-1 was measured. RESULTS: Compared to controls, FH subjects had lower content of phospholipids in their HDL3 subfraction and a higher serum ICAM-1 level. No differences in sVCAM-1 were observed. HDL3 isolated from FH with body mass index(BMI)>25 and from FH subjects with premature CAD contained higher content of triglycerides compared to the HDL3 from FH subjects with BMI<25 and without CAD, respectively. Most important, when testing the function of HDL3 in the two FH subgroups characterized by elevated BMI and premature CAD, lower inhibition of ICAM-1 expression on HUVEC was observed. CONCLUSIONS: The altered composition of HDL3 from FH subjects with BMI>25 and FH subjects with premature CAD may be responsible for a HDL3 subfraction with less protective properties assessed as inhibition of ICAM-1 expression on HUVEC consequently leading to more proatherogenic endothelial surface.


Subject(s)
Arteriosclerosis/prevention & control , Hyperlipoproteinemia Type II/blood , Lipoproteins, HDL/blood , Adult , Arteriosclerosis/blood , Case-Control Studies , Female , Humans , Immunoenzyme Techniques , Intercellular Adhesion Molecule-1/blood , Lipoproteins, HDL3 , Male , Middle Aged , Vascular Cell Adhesion Molecule-1/blood
11.
Hum Mutat ; 18(1): 83-4, 2001.
Article in English | MEDLINE | ID: mdl-11438998

ABSTRACT

Hypophosphatasia is a rare inherited disorder characterized by defective bone mineralization and deficiency of serum and tissue liver/bone/kidney tissue alkaline phosphatase (L/B/K ALP) activity. We report here the characterization of tissue-nonspecific alkaline phosphatase (TNSALP) gene mutations in a series of 11 families affected by various forms of hypophosphatasia. Nineteen distinct mutations were found, 7 of which were previously reported. Eleven of the 12 new mutations were missense mutations (Y11C, A34V, R54H, R135H, N194D, G203V, E218G, D277Y, F310G, A382S, V406A), the last one (998-1G>T) was a mutation affecting acceptor splice site.


Subject(s)
Alkaline Phosphatase/genetics , Hypophosphatasia/enzymology , Hypophosphatasia/genetics , Mutation/genetics , Adult , Alkaline Phosphatase/metabolism , Alleles , DNA Mutational Analysis , Exons/genetics , Female , Gene Frequency/genetics , Genetic Testing , Humans , Infant , Male , Mutation, Missense/genetics , Polymorphism, Genetic/genetics , RNA Splice Sites/genetics
12.
Autoimmunity ; 29(2): 93-101, 1999.
Article in English | MEDLINE | ID: mdl-10433070

ABSTRACT

Interleukin-1beta (IL-1beta) has been implicated to play an important role in the autoimmune beta cell lesion of insulin-dependent diabetes mellitus (IDDM) because of its inhibition of insulin secretion, direct islet cytotoxicity and alteration of islet cell antigen expression. We have previously demonstrated that IL-1beta inhibits glutamic acid decarboxylase-65 (GAD-65) and increases heat shock protein-70 (HSP-70) expression in islet cells. IL-1beta stimulates the inducible form of nitric oxide (NO) synthase and the resultant increased NO mediates many of IL-1beta's effects. In this study we investigated the role of the NO pathway in mediating the effects of IL-1beta on GAD-65 and HSP-70 expression and on insulin secretion. Islets isolated from Sprague-Dawley rats were cultured with IL-1beta and aminoguanidine (AG), an inhibitor of inducible NO synthase, individually and in combination for 24 h. Accumulated nitrite production, insulin release and islet expression of GAD-65 and HSP-70 were measured. We found that (1) IL-1beta at 10 U/ml increased nitrite production, inhibited insulin release, increased HSP-70 expression and decreased GAD-65 expression. (2) AG alone at 1 mM/ml had no effect on nitrite production, insulin release, GAD-65 and HSP-70 expression. (3) In combination, AG completely blocked IL-1beta increased nitrite production, reversed IL-1beta inhibited insulin release by approximately 50%, completely reversed IL-1beta increased HSP-70 expression, but did not reverse IL-1beta inhibited GAD-65 expression. Our findings indicate that the effect of IL-1beta on HSP-70 expression is mediated by NO production, whereas a NO-independent pathway is involved in the effect of IL-1beta on GAD-65 expression and insulin secretion.


Subject(s)
Glutamate Decarboxylase/antagonists & inhibitors , HSP70 Heat-Shock Proteins/biosynthesis , Interleukin-1/pharmacology , Nitric Oxide/physiology , Animals , Diabetes Mellitus, Type 1/etiology , Guanidines/pharmacology , Insulin/metabolism , Insulin Secretion , Male , Nitric Oxide Synthase/biosynthesis , Nitric Oxide Synthase Type II , Rats , Rats, Sprague-Dawley
13.
J Nutr Biochem ; 10(6): 345-52, 1999 Jun.
Article in English | MEDLINE | ID: mdl-15539309

ABSTRACT

Vitamin A plays an important role in reducing infectious disease morbidity and mortality by enhancing immunity, an effect that is partly mediated by macrophages. Thus, knowing how these cells take up vitamin A is important. The results in the present study demonstrate that J774 macrophages efficiently take up chylomicron remnant retinyl esters and retinol-binding protein (retinol-RBP) bound retinol by specific and saturable mechanisms. The binding of (125)I-RBP to plasma membrane vesicles demonstrated that the macrophage receptor had a similar binding affinity, as was discovered previously for other cells. The B(max) for the macrophages was smaller than the values reported for placenta, bone marrow, and kidney, but larger than that reported for liver. The J774 cells also bound and took up [(3)H]retinol-RBP. Approximately 50 to 60% of the uptake may compete with excess unlabeled retinol-RBP and approximately 30 to 40% with excess transtyrethin. Following the uptake of [(3)H]retinol-RBP, an extensive esterification occurred: After 5 hours of incubation, 77.8 +/- 3.9% (SD; n = 3) of the cellular radioactivity was recovered as retinyl esters. The J774 cells also demonstrated saturable binding of chylomicron remnant [(3)H]retinyl esters, and a continuous uptake at 37 degrees C followed by an extensive hydrolysis of the retinyl esters. Binding could be inhibited by approximately 50% by excess unlabeled low density lipoprotein (LDL). In addition, lipoprotein lipase increased the binding of chylomicron remnant [(3)H]retinyl esters by approximately 30% and the uptake of chylomicron remnant [(3)H]retinyl ester by more than 300%. Furthermore, because sodium chlorate reduced binding with 40% and uptake with 55%, the results suggest that proteoglycans are involved in the uptake. Thus, the results suggest that both LDL receptor and LDL-related protein are involved in the uptake of chylomicron remnant [(3)H]retinyl ester in macrophages.

14.
Environ Pollut ; 53(1-4): 265-71, 1988.
Article in English | MEDLINE | ID: mdl-15092555

ABSTRACT

Oats (Avena sativa L. cv Titus) were exposed to low concentrations of O3 in an assimilation chamber system. Net photosynthesis (net CO2 uptake), measured before and after O3 fumigation, showed significantly different responses for leaves of different age. The oldest active leaf was the most sensitive to O3. Net photosynthesis was depressed after 2 h with 0.075 ppm (150 microg m(-3)) O3. For leaves exposed to 0.150 ppm (300 microg m(-3)) O3 for 2 h, net photosynthesis was reduced significantly for 4 h, after which recovery occurred, nearly reaching the preexposure level 19 h after the exposure. Dark respiration was initially more than doubled after exposure to 0.130 ppm (260 microg m(-3)) O3. There was no visible injury after any of the experiments. The results indicate that O3 may cause crop losses through effects on photosynthesis even in Scandinavia, where a typical O3 episode lasts 1 to 2 h, and the concentration seldom exceeds 0.150 ppm.

15.
Food Chem Toxicol ; 48(8-9): 2193-9, 2010.
Article in English | MEDLINE | ID: mdl-20488221

ABSTRACT

N-Acetyl-L-serine (NAS) is a component of dietary proteins and a minor constituent of foods as a free amino acid. The current paper reports the outcome of toxicology studies conducted to assess the safety of NAS. No evidence of mutagenicity was observed in the reverse bacterial mutation assay. Genotoxicity was not observed in the bone marrow micronucleus assay conducted in mice. No mortalities or evidence of adverse effects were observed in Sprague-Dawley (SD) rats following acute oral administration at a dose of 2000 mg of NAS/kg of body weight. Similarly, no evidence of adverse effects was observed in SD rats following repeated dose dietary exposure (28-days) to targeted doses of 100, 500, or 1000 mg of NAS/kg of body weight/day. All rats survived until scheduled sacrifice and no biologically significant differences were observed in any of the response variables from the NAS exposure groups compared with untreated control groups. Based on these results, NAS does not represent a risk for mutagenicity or genotoxicity, is not acutely toxic, and the no-observed-adverse-effect-level (NOAEL) for systemic toxicity from repeated dose dietary exposure to NAS is 839.7 and 893.6 mg of NAS/kg of body weight/day for male and female rats, respectively.


Subject(s)
Mutagens , Serine/analogs & derivatives , Animals , Blood Cell Count , Blood Chemical Analysis , Blood Coagulation , Body Weight/drug effects , Bone Marrow Cells , Diet , Dose-Response Relationship, Drug , Eating , Erythrocytes/drug effects , Female , Male , Mice , Mice, Inbred ICR , Micronucleus Tests , Mutagenicity Tests , No-Observed-Adverse-Effect Level , Organ Size/drug effects , Rats , Rats, Sprague-Dawley , Serine/toxicity
16.
Food Chem Toxicol ; 48(7): 1919-25, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20434501

ABSTRACT

N-acetyl-L-threonine (NAT) is a dietary constituent that has been identified at low concentrations (< 1 microg/g fresh weight) in numerous foods. The current paper reports the outcome of toxicology studies conducted to assess the effects of NAT. No evidence of mutagenicity or genotoxicity was observed in in vitro bacterial or in vivo mammalian studies. No mortalities or evidence of adverse effects were observed in Sprague-Dawley (SD) rats following acute oral administration of 2000 mg of NAT/kg of body weight (kg of bw). A 28-day repeated dose toxicity study was conducted in SD rats by incorporating NAT into diets at concentrations targeting up to 1000 mg of NAT/kg of bw/day. All rats survived until scheduled sacrifice and no biologically significant differences were observed in any of the NAT treatment groups for body weights, feed consumption, clinical signs, behavioral, ophthalmology, hematology, coagulation, clinical chemistry, organ weights, or gross or microscopic changes. Based on these results, NAT does not represent a risk for mutagenicity or genotoxicity, is not acutely toxic, and the no-observed-adverse-effect-level (NOAEL) for systemic toxicity from repeated dose dietary exposure to NAT is 848.5 and 913.6 mg/kg of bw/day for male and female SD rats, respectively.


Subject(s)
Threonine/analogs & derivatives , Animals , Behavior, Animal/drug effects , Blood Cell Count , Blood Coagulation/drug effects , Body Weight/drug effects , Bone Marrow/drug effects , Diet , Eating/drug effects , Eye Diseases/chemically induced , Eye Diseases/pathology , Female , Male , Mice , Mice, Inbred ICR , Micronucleus Tests , Motor Activity/drug effects , Mutagenicity Tests , No-Observed-Adverse-Effect Level , Organ Size/drug effects , Rats , Rats, Sprague-Dawley , Threonine/toxicity
18.
J Periodontal Res ; 41(3): 208-13, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16677290

ABSTRACT

BACKGROUND AND OBJECTIVE: Enamel matrix derivative (EMD), extracted from porcine tooth buds, has been shown to promote periodontal healing in patients with severe periodontitis. This involves modulation of the inflammatory response followed by the onset of periodontal regeneration. Based on these observations, we examined the ability of EMD to modulate the release of a pro-inflammatory cytokine [tumor necrosis factor (TNF)-alpha], an anti-inflammatory cytokine (interleukin-10) and a chemokine (interleukin- 8) in whole human blood challenged by bacterial cell wall components. MATERIAL AND METHODS: Whole blood from healthy donors was challenged by lipopolysaccharide or peptidoglycan and incubated with different concentrations of EMD or a cAMP analogue 8-(4-chlorophenyl)thio-cAMP (8-CPT-cAMP). TNF-alpha, interleukin-8 and interleukin-10 were analysed from plasma by enzyme-linked immunosorbent assay (ELISA) while cAMP levels of peripheral blood mononuclear cell lysates were analysed by enzyme immunoassay (EIA). RESULTS: We found that EMD attenuated the release of TNF-alpha and interleukin-8 in whole blood from healthy donors challenged by lipopolysaccharide or peptidoglycan, while the release of interleukin-10 was unchanged. Enamel matrix derivative also produced a four-fold increase in the cAMP levels of peripheral blood mononuclear cell lysates. Like EMD, 8-CPT-cAMP attenuated the formation of TNF-alpha, but not of interleukin-10, in blood challenged by lipopolysaccharide. CONCLUSION: Enamel matrix derivative limits the release of pro-inflammatory cytokines induced by lipopolysaccharide or peptidoglycan in human blood, suggesting that it has anti-inflammatory properties. We propose that this effect of EMD is, at least partly, secondary to an increase in the intracellular levels of cAMP in peripheral blood mononuclear cells.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Dental Enamel Proteins/pharmacology , Animals , Cyclic AMP/analogs & derivatives , Cyclic AMP/blood , Cyclic AMP/pharmacology , Enzyme Inhibitors/pharmacology , Escherichia coli , Humans , Interleukin-10/blood , Interleukin-8/blood , Leukocytes, Mononuclear/drug effects , Leukocytes, Mononuclear/enzymology , Lipopolysaccharides/pharmacology , Peptidoglycan/pharmacology , Staphylococcus aureus , Swine , Thionucleotides/pharmacology , Tumor Necrosis Factor-alpha/analysis , Tumor Necrosis Factor-alpha/drug effects
19.
Scand J Immunol ; 62(2): 148-54, 2005 Aug.
Article in English | MEDLINE | ID: mdl-16101821

ABSTRACT

Disseminated fungal infections are increasing. However, the interactions between the body's largest population of tissue macrophages, the Kupffer cells and the fungal pathogens are scarcely understood. The aim of this study was to examine the involvement of Toll-like receptor 4 (TLR4) signalling in cytokine production, using primary cultures of rat and murine Kupffer cells exposed to Aspergillus fumigatus and Candida albicans hyphae and conidia. All fungal components induced the release of tumour necrosis factor-alpha (TNF-alpha), but with delayed kinetics compared with lipopolysaccharide (LPS). Candida albicans was the most potent inducer of TNF-alpha protein and mRNA and the only inducer of interleukin-10 (IL-10) in rat Kupffer cells. All fungal components induced enhanced mRNA levels of macrophage inhibitory protein-2 (MIP-2) in the cells, similar to LPS. Inhibitors of Src tyrosine kinases added to cells prior to stimulation led to attenuation in the release of both TNF-alpha (60%, P < 0.05) and IL-10 (70%, P < 0.05) induced by C. albicans conidia but did not influence the LPS-mediated cytokine release. Murine Kupffer cells (C57BL/10J) also released TNF-alpha as well as the chemokines keratinocyte-derived chemokine (KC) and MIP-2 in response to fungal component. Surprisingly, Kupffer cells from TLR4-deficient C57BL/ScCr mice exhibited significantly enhanced production of KC and MIP-2 upon stimulation by fungal components compared with control littermates (P < 0.05). Our study demonstrates that Aspergillus and Candida components induce cytokine production in rat Kupffer cells and that the response to C. albicans conidia involves Src tyrosine kinases. The experiments with TLR4-deficient Kupffer cells suggest that the cytokine response in these cells to fungal component is not mediated by TLR4.


Subject(s)
Aspergillosis/immunology , Aspergillus fumigatus/immunology , Candida albicans/immunology , Candidiasis/immunology , Cytokines/immunology , Kupffer Cells/immunology , Protein-Tyrosine Kinases/immunology , Animals , Aspergillosis/microbiology , Candidiasis/microbiology , Chemokine CXCL2 , Chemokines, CXC/immunology , Cytokines/biosynthesis , Intercellular Signaling Peptides and Proteins/immunology , Interleukin-10/genetics , Interleukin-10/immunology , Kupffer Cells/enzymology , Kupffer Cells/microbiology , Male , Mice , Mice, Inbred C57BL , Protein Kinase Inhibitors/pharmacology , RNA, Messenger/chemistry , RNA, Messenger/genetics , Rats , Rats, Inbred SHR , Receptors, Immunologic/immunology , Reverse Transcriptase Polymerase Chain Reaction , Toll-Like Receptor 4 , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/immunology , p38 Mitogen-Activated Protein Kinases/immunology , src-Family Kinases/antagonists & inhibitors , src-Family Kinases/immunology
20.
Acta Paediatr ; 90(11): 1321-8, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11808907

ABSTRACT

UNLABELLED: The purpose of this study was to describe the normal variation in perianal anatomy in preschool children, selected for non-abuse, and to compare the findings in two examination positions. A letter of invitation was sent to 3773 children, after which 305 children (103 boys and 202 girls) were recruited. Inclusion in the study was based on self-selection, whereby parents who did not suspect any occurrence of sexual abuse of their child gave informed consent to participate. The mean age of the children was 5.63 y (range: 5.13-6.75). An anal examination was performed in the left lateral position (LLP) and the prone knee-chest position (KCP), for approximately 30 s each. A colposcope and a camera were used. All data were systematically analysed for gender differences, and a paired sample test was used to compare findings in LLP and KCP. Venous congestion in LLP and external anal dilatation in both positions were significantly more common in girls, while midline depressions and smooth areas (both positions) were significantly more common in boys. External and total anal dilatation, midline smooth areas and depressions and the occurrence of a prominent anal verge were significantly more common in the KCP. The finding of total anal dilatation was rare. CONCLUSION: We observed several gender and position differences in perianal anatomy, and most of these findings seem to be related to structure and tone in the anal muscles.


Subject(s)
Anal Canal/anatomy & histology , Child Abuse, Sexual/diagnosis , Anal Canal/pathology , Child , Child, Preschool , Dilatation, Pathologic , Female , Humans , Male , Posture , Reference Values , Sex Factors , Statistics, Nonparametric
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