Subject(s)
Diabetes Mellitus , Global Health , Precision Medicine , Humans , Diabetes Mellitus/therapyABSTRACT
Electricity demand and its typical load pattern are usually affected by many endogenous and exogenous factors to which the generation system must accordingly respond through utility operators. Lockdown measures to prevent the spread of COVID-19 imposed by many countries have led to sudden changes in socioeconomic habits which have had direct effects on the electricity systems. Therefore, a detailed analysis of how confinement measures have modified the electricity consumption in Spain, one of the countries most affected by this pandemic, has been performed in this work. Its electricity consumption has decreased by 13.49% from March 14 to April 30, compared to the average value of five previous years. Daily power demand profiles, especially morning and evening peaks, have been modified at homes, hospitals, and in the total power demand. These changes generate a greater uncertainty for the System Operator when making demand forecasts, but production deviations have increased by only 0.1%, thanks to the presence of a diversified generation mix, which has been modified during this period, increasing the proportion of renewable sources and decreasing CO2 emissions.
ABSTRACT
AIM: To compare demographic and clinical characteristics among children from ethnic minorities and non-Hispanic white children with new-onset autoimmune Type 1 diabetes. METHODS: We analysed a single-centre series of 712 children with new-onset autoimmune Type 1 diabetes between January 2008 and March 2011. The median (range) age was 9.7 (0.3-18.1) years, the mean (sd) BMI percentile was 69.7 (25.4) and 48.3% of the cohort were girls. The cohort comprised 57.3% non-Hispanic white, 20.5% Hispanic and 14.8% African-American children, and 7.4% were of other, mixed or unknown race. RESULTS: The Hispanic subgroup, compared with non-Hispanic white subgroup, had a higher mean (sd) C-peptide level [0.82 (1.62) vs 0.55 (0.47) ng/ml; P=0.004), and a greater proportion of children with elevated BMI (overweight or obesity; 49.6% vs 32.5%; P<0.001) and diabetic ketoacidosis (51.8% vs 38.2%; P=0.006). The African-American group had a higher mean (sd) glucose level [24.4 (12.8) vs 21.4 (10.7) mmol/l; P=0.017], a greater proportion of children with ketoacidosis (56.7% vs 38.2%; P=0.001), a greater proportion with elevated BMI (52.9% vs 32.5%; P<0.001), and a lower proportion of children at pre-pubertal stage (49.0% vs 61.6%; P=0.01), and tended to have higher C-peptide levels [0.65 (0.59) vs 0.55 [0.47] ng/ml; P=0.079) compared with the non-Hispanic white children. The differences in C-peptide levels compared with non-Hispanic white children persisted for Hispanic (P=0.01) but not African-American children (P=0.29) after adjustment for age, sex, BMI, ketoacidosis, glucose, Tanner stage and autoantibody number. CONCLUSION: At the onset of paediatric autoimmune Type 1 diabetes, Hispanic, but not African-American children had higher C-peptide levels, after adjustment for potential confounders, compared with non-Hispanic white children. These findings suggest that ethnicity may contribute to the heterogeneity of Type 1 diabetes pathogenesis, with possible implications for intervention.
Subject(s)
Diabetes Mellitus, Type 1/ethnology , Ethnicity/statistics & numerical data , Racial Groups/statistics & numerical data , Adolescent , Child , Child, Preschool , Cohort Studies , Cross-Sectional Studies , Female , Humans , Infant , Male , Overweight/complications , Overweight/ethnology , Pediatric Obesity/complications , Pediatric Obesity/ethnologyABSTRACT
AIM: To study whether DPD epitope-specific glutamate decarboxylase autoantibodies are found more frequently in children with milder forms of Type 1 diabetes. METHODS: We prospectively evaluated 75 children with new-onset autoimmune Type 1 diabetes, in whom we collected demographic, anthropometric and clinical data and measured islet autoantibodies. Glutamate decarboxylase 65 autoantibody-positive samples were analysed for epitope specificities using recombinant Fab against the DPD-defined epitope of glutamate decarboxylase 65. RESULTS: After adjustment for age, positive DPD epitope recognition was significantly associated with higher C-peptide levels at onset (P = 0.02, r2 =0.21, n = 35), and high DPD recognition in the highest quartile tended to be associated with HbA1c ≤ 53 mmol/mol (7%) at the last follow-up [mean (sd) follow-up 1.3 (0.4) years; P = 0.07; for the model, P = 0.044, n = 30)]. Age- and sex-adjusted BMI percentile was significantly correlated with recognition of the DPD-defined epitope (P < 0.03, r2 =0.14, n = 34), but this correlation was driven by the older age group (age ≥ 10 years; P = 0.016, r2 =0.27, n = 21) and was not significant in younger children (P = 0.93, n = 13). There were no independent associations with sex, race/ethnicity, diabetic ketoacidosis, HbA1c , HLA DR3-DQ2/DR4-DQ8 or autoantibody number. CONCLUSIONS: Our findings suggest that recognition of the DPD-defined glutamate decarboxylase 65 autoantibody epitope at Type 1 diabetes onset is directly associated with ß-cell function, BMI and age, which supports the hypothesis that immunological factors contribute to the clinical heterogeneity of Type 1 diabetes. Larger studies relating epitope-specific glutamate decarboxylase 65 autoantibody to clinical phenotype in children with Type 1 diabetes are warranted.
Subject(s)
Autoantibodies/blood , Diabetes Mellitus, Type 1/blood , Glutamate Decarboxylase/immunology , Adolescent , Antibody Specificity , Autoantibodies/chemistry , C-Peptide/blood , Cation Transport Proteins/immunology , Child , Child, Preschool , Diabetes Mellitus, Type 1/immunology , Epitopes/immunology , Female , Glutamate Decarboxylase/chemistry , Humans , Infant , Male , Receptor-Like Protein Tyrosine Phosphatases, Class 8/immunology , Zinc Transporter 8ABSTRACT
AIMS: To test the hypothesis that non-obese individuals with childhood-onset Type 1 diabetes and the rs7903146 TT genotype would be less likely to have high-risk human leukocyte antigen (HLA) genotypes and alleles. METHODS: We studied a cohort of 105 non-obese participants in the T1D Exchange Biobank Residual Insulin Study who had childhood-onset Type 1 diabetes [mean (sd) age at onset and recruitment, respectively, 9.9 (4.15) and 14.4 (4.13) years; 84.8% non-Hispanic white]. We analysed islet autoantibodies (glutamic acid decarboxylase 65, islet cell autoantigen 512/islet antigen-2 and zinc transporter 8), non-fasting random C-peptide levels, HLA type and TCF7L2 single nucleotide polymorphism rs7903146 in this cohort. RESULTS: None of the 13 individuals with the rs7903146 TT genotype carried the highest Type 1 diabetes risk HLA genotype, i.e. DRB1*03:01/DR4 (DRB1*0401, *04:05 or *04:02), compared with 29.4% (27/92) of those without it (P=0.023). The DRB1*03:01 allele was present in 15.4% (2/13) of individuals with the single nucleotide polymorphism, compared with 59.8% (55/92) of those without it (P=0.003). Analyses restricted to autoantibody-positive individuals (n=80) yielded similar results. The HLA DRB1*15:01 allele, which affords dominant protection against Type 1 diabetes, was found in one participant, who had multiple islet autoantibodies and carried the rs7903146 TT genotype. CONCLUSIONS: These findings further support the hypothesis that TCF7L2 gene variation contributes to diabetogenesis in a subset of young people with Type 1 diabetes, opening possible new pathways for therapy and prevention.
Subject(s)
Diabetes Mellitus, Type 1/genetics , Adolescent , Autoantibodies/immunology , C-Peptide/metabolism , Child , Child, Preschool , Cohort Studies , Diabetes Mellitus, Type 1/immunology , Female , Genetic Predisposition to Disease , Glutamate Decarboxylase/immunology , HLA-DRB1 Chains/genetics , Humans , Male , Polymorphism, Single Nucleotide , Transcription Factor 7-Like 2 Protein/genetics , Zinc Transporter 8/immunologyABSTRACT
BACKGROUND/OBJECTIVE: Obesity increases the risk of cardiovascular disease and diabetic complications in type 1 diabetes. Adipokines, which regulate obesity-induced inflammation, may contribute to this association. We compared serum adipokines and inflammatory cytokines in obese and lean children with new-onset autoimmune type 1 diabetes. SUBJECTS AND METHODS: We prospectively studied 32 lean and 18 obese children (age range: 2-18 yr) with new-onset autoimmune type 1 diabetes and followed them for up to 2 yr. Serum adipokines [leptin, total and high molecular weight (HMW) adiponectin, omentin, resistin, chemerin, visfatin], cytokines [interferon (IFN)-gamma, interleukin (IL)-10, IL-12, IL-6, IL-8, and tumor necrosis factor (TNF)-alpha] and C-reactive protein (CRP) were measured at a median of 7 wk after diagnosis (range: 3-16 wk). RESULTS: Lean children were 71.9% non-Hispanic White, 21.9% Hispanic, and 6.3% African-American, compared with 27.8, 55.6, and 16.7%, respectively, for obese children (p = 0.01). Compared with lean children, obese children had significantly higher serum leptin, visfatin, chemerin, TNF-alpha and CRP, and lower total adiponectin and omentin after adjustment for race/ethnicity and Tanner stage. African-American race was independently associated with higher leptin among youth ≥10 yr (p = 0.007). Leptin levels at onset positively correlated with hemoglobin A1c after 1-2 yr (p = 0.0001) independently of body mass index, race/ethnicity, and diabetes duration. Higher TNF-alpha was associated with obesity and female gender, after adjustment for race/ethnicity (p = 0.0003). CONCLUSION: Obese children with new-onset autoimmune type 1 diabetes have a proinflammatory profile of circulating adipokines and cytokines that may contribute to the development of cardiovascular disease and diabetic complications.
Subject(s)
Adiposity , Biomarkers/blood , Diabetes Mellitus, Type 1/blood , Pediatric Obesity/blood , Thinness/blood , Adipokines/blood , Adolescent , Age of Onset , Child , Child, Preschool , Cytokines/blood , Diabetes Mellitus, Type 1/complications , Diabetes Mellitus, Type 1/diagnosis , Diabetes Mellitus, Type 1/epidemiology , Female , Follow-Up Studies , Humans , Male , Pediatric Obesity/complications , Thinness/complicationsABSTRACT
The enteric myxozoan parasites Enteromyxum leei (Diamant, Lom et Dyková) and Enteromyxum scophthalmi Palenzuela, Redondo et Álvarez-Pellitero are responsible for high weight loss in infected fish, which leads to subchronic disease and low mortality rates in gilthead sea bream (GSB), Sparus aurata L., and to high mortality rates in turbot, Psetta maxima (L.). The detection of initial parasite stages in histological sections is particularly difficult, but can be simplified by means of specific antibodies. Rabbit polyclonal antibodies (pAbs) were raised against E. scophthalmi and E. leei, and direct enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry were used to characterize their sensitivity and specificity. Both pAbs were adsorbed (apAb) with non-infected intestines to avoid non-specific labelling of fish tissues and to improve their specificity. The highest titre obtained in ELISA was 1: 32 000 for apAb-Eleei and 1:16 000 for apAb-Escoph. Working dilutions in immunohistochemistry were 1:1000 for apAb-Eleei and 1:8000 for apAb-Escoph. Both apAbs labelled proliferative and sporogonic stages with high specificity. apAb-Escoph was very specific, whereas apAb-Eleei cross-reacted with Sphaerospora dicentrarchi Sitjà-Bobadilla et Álvarez-Pellitero and Sphaerospora testicularis Sitjà-Bobadilla et Álvarez-Pellitero, suggesting the presence of shared antigens. These pAbs stand as new tools for antigenic characterization and the diagnosis of both Enteromyxum species.
Subject(s)
Antibodies/immunology , Antigens/immunology , Fish Diseases/immunology , Flatfishes , Myxozoa/physiology , Parasitic Diseases, Animal/immunology , Animals , Cross Reactions , Enzyme-Linked Immunosorbent Assay/veterinary , Fish Diseases/parasitology , Immunohistochemistry/veterinary , Parasitic Diseases, Animal/parasitology , Species SpecificityABSTRACT
In the last decade, a new parasite that causes severe losses has been detected in farmed turbot Psetta maxima (L.), in north-western Spain. The parasite was classified as a myxosporean and named Enteromyxum scophthalmi. The aim of this study was to characterize the main histological changes that occur in E. scophthalmi-infected turbot. The parasite provoked catarrhal enteritis, and the intensity of the lesions was correlated with the progression of the infection and with the development of the parasite. Infected fish were classified into 3 groups, according to the lesional degree they showed (slight, moderate and severe infections). In fish with slight infections, early parasitic stages were observed populating the epithelial lining of the digestive tract, without eliciting an evident host response. As the disease progressed, catarrhal enteritis was observed, the digestive epithelium showed a typical scalloped shape and the number of both goblet and rodlet cells was increased. Fish with severe infections suffered desquamation of the epithelium, with the subsequent release of parasitic forms to the lumen. The dislodged enterocytes underwent anoikis, a mode of apoptosis triggered by the loss of anchorage, which might facilitate spreading of the parasite. Lymphohaematopoietic depletion was also observed, mainly in head kidney and spleen, which could contribute to the high virulence of this parasite.
Subject(s)
Enteritis/veterinary , Fish Diseases/parasitology , Flatfishes , Myxozoa/isolation & purification , Parasitic Diseases, Animal/parasitology , Animals , Enteritis/parasitology , Enteritis/pathology , Fish Diseases/pathology , Microscopy, Electron , Myxozoa/ultrastructureABSTRACT
The existence and localisation of carbohydrate terminals in Enteromyxum scophthalmi stages was investigated at light (LM) and transmission electron microscopes (TEM) using lectin histochemistry techniques, with the aim of contributing to elucidate the participation of carbohydrate-lectin interactions in the parasite invasion and relationships with the fish host. The presence of abundant mannose and/or glucose residues was demonstrated by the intense staining by concanavalin A at both LM and TEM. The staining pattern obtained with soybean agglutinin and Bandeiraea simplicifolia I (BSI) indicated the abundance of N-acetyl-galactosamine and D-galactose at a lesser extent. The lectins wheat germ agglutinin, BSI and Ulex europaeus agglutinin produced weaker marks. Most lectins recognised structures present in both pre-sporogonic and sporogonic stages, though the glycosidic pattern and/or staining intensity varied between developmental stages. No staining was obtained with Sambucus nigra agglutinin. The TEM studies demonstrated glucose-mannose, N-acetyl-glucosamine, N-acetyl-galactosamine and alpha-D-galactose as dominant structures at the parasite membrane and host-parasite interface, suggesting a role in host-parasite interactions. All these terminals were also detected in the mitochondria of P cells and were scant in the S cells and nuclei. In turbot intestine, mannose-glucose terminals and N-acetyl-glucosamine were labelled on the epithelial brush border and in the mucous cells and rodlet cells. The relevance of these findings in relation to the host-parasite interaction is discussed.
Subject(s)
Carbohydrates/analysis , Cnidaria/chemistry , Flatfishes/parasitology , Acetylgalactosamine/analysis , Acetylglucosamine/analysis , Animals , Cell Membrane/chemistry , Cnidaria/cytology , Cnidaria/ultrastructure , Epithelial Cells/chemistry , Galactose/analysis , Glucose/analysis , Host-Parasite Interactions , Intestinal Mucosa/chemistry , Lectins/metabolism , Mannose/analysis , Microscopy , Microscopy, Electron, Transmission , Staining and Labeling/methodsABSTRACT
In the course of experimental infections of gilthead sea bream Sparus aurata with the myxozoan Enteromyxum leei, stages of an unidentified myxozoan were observed attached to the intestinal brush border of some fish. Infection levels of the parasite, which was named "epi-epithelial myxosporean" (EEM) were recorded, and its structure was studied by light microscopy (LM) and electron microscopy (EM). In situ hybridisation (ISH) probes specific for E. leei were developed and used to differentiate between the two parasites. The EEM parasite was observed only in epi-epithelial position on the intestine mucosa and never in any of the other tissues studied (kidney and gall bladder). Prevalence was variable, with values reaching 40.2%. With transmission EM, trophozoites displayed pseudopodia-like projections inserted in between the enterocyte microvilli, producing an intimate interface. No mucosal histopathology that could be attributed to the myxozoan was found. EEM stages did not stain with the E. leei-specific ISH probes. From the results of the LM, EM and ISH studies, we conclude that the EEM parasite found in gilthead sea bream intestine in both Mediterranean and Red Sea sites is a coelozoic myxosporean, distinct from E. leei.
Subject(s)
Epithelial Cells/parasitology , Eukaryota/ultrastructure , Fish Diseases/parasitology , Intestinal Mucosa/parasitology , Protozoan Infections, Animal/parasitology , Sea Bream/parasitology , Animals , In Situ Hybridization , Indian Ocean , Mediterranean Sea , Microscopy, Electron, Scanning , Microscopy, Electron, TransmissionABSTRACT
An epidemiological cohort study of Enteromyxum scophthalmi in cultured turbot was performed on a farm in North Western Spain. Four different ongrowing stocks (A, B, C, D) were monitored monthly until market size. Fish from stocks C and D were divided into 2 subgroups, receiving filtered (CF and DF) or unfiltered (CUF and DUF) water. The lack of water filtration was positively associated with infection prevalence, as all fish kept in filtered water remained uninfected. Parasite abundance varied seasonally (P<0.05) in stock B and subgroup CUF. Infection was also associated (P<0.05) with host weight, and the highest prevalences and intensities were detected in 101-200 g and 201-300 g fish. Distribution pattern of E. scophthalmi in subgroups CUF and DUF had a variance higher than the mean, indicating overdispersion. The minimum period necessary for the first detection of the parasite and for the appearance of disease symptoms and mortality, varied depending on the stock and introduction date, although a long pre-patent period was always observed. Several factors, such as host density, parasite recruitment and parasite-induced fish mortality can contribute to the observed distribution pattern. Risk factors found to be associated with E. scophthalmi infection, including water quality and accumulation of infective stages in the culture tanks, should be considered when designing control strategies to prevent the introduction and spread of infective stages in the facilities.
Subject(s)
Fish Diseases/epidemiology , Flatfishes/parasitology , Intestinal Diseases, Parasitic/veterinary , Protozoan Infections, Animal/epidemiology , Animals , Aquaculture/methods , Aquaculture/standards , Body Weight , Cohort Studies , Eukaryota , Fish Diseases/parasitology , Intestinal Diseases, Parasitic/epidemiology , Intestinal Diseases, Parasitic/parasitology , Prevalence , Protozoan Infections, Animal/parasitology , Random Allocation , Risk Factors , Seasons , Spain/epidemiology , Time FactorsABSTRACT
The innate and adaptive immune responses against Enteromyxum scophthalmi was studied in turbot (Scopthalmus maximus (L.)) experimentally exposed to the parasite by cohabitation. Haematological, histopathological, cellular and humoral factors were determined in samples taken from control (CTRL) and recipient (RCPT, naïve fish cohabited with donor infected fish) animals at 0, 20, 29, 40 and 43 days post exposure (p.e). Infection was first detected at day 20 p.e. and prevalence reached 100% at 40 days p.e, when first mortalities occurred. A significant reduction in weight and condition factor was found in RCPT, though no significant differences in haematocrit or serum protein levels were detected between CTRL and RCPT. Some immune effectors were clearly activated in RCPT: the percentage of circulating granulocytes was significantly increased, as well as the number of blood cells positive in the respiratory burst assay; leucocyte infiltration in intestine was found mainly on days 20 and 29 p.e.; total serum antiproteases and alpha-2-macroglobulin levels were higher in most of the samplings, with significant differences on the last sampling. Other effectors were clearly down regulated in RCPT: haematopoietic depletion appeared in head kidney from day 29 p.e. onwards, and the number of apoptotic cells and MMC increased in head kidney and spleen; the percentage of lymphocytes decreased progressively and significantly; a clear, but not statistically significant, drop in serum complement was registered at 40 days p.e.; also, a significant decrease occurred in serum lysozyme at 29 days p.e. No specific antibodies against the parasite were detected in any sampling.
Subject(s)
Eukaryota/immunology , Fish Diseases/immunology , Flatfishes/immunology , Flatfishes/parasitology , Immunity, Innate/immunology , Protozoan Infections, Animal/immunology , Animals , Blood Cells/immunology , Complement Pathway, Alternative/physiology , Fish Diseases/parasitology , Fish Diseases/pathology , Granulocytes/cytology , Immunity, Active , Kidney/immunology , Kidney/pathology , Muramidase/blood , Protease Inhibitors/blood , Protozoan Infections, Animal/pathology , Spleen/immunology , Spleen/parasitology , Spleen/pathology , Time Factors , alpha-Macroglobulins/analysisABSTRACT
Immunohistochemistry and enzyme-linked immunosorbent assays were developed for the detection of specific antibodies against the myxosporean parasite Enteromyxum scophthalmi in turbot (Scophthalmus maximus L.). Fish which had survived a previous epizootic were exposed to the parasite by cohabitation with infected animals, and 83 days later the plasma was tested for the presence of antibodies. Plasma of non-exposed fish was used as negative control. Immunohistochemistry (IHC) using rabbit anti-turbot IgM antibody was first used to detect these antibodies, and to study to which parasite structures they were directed against. Also, an antibody-ELISA using whole cell lysates of the parasite as antigen, and a monoclonal antibody anti-turbot IgM, was developed. All the exposed fish were found to have specific antibodies against the parasite, and none of them developed signs of disease or died during the experiment. Primary cells were the main parasite stage immunolabelled, and the staining was distinctly located on the cytoplasm and the cytoplasmic membrane. IHC was more sensitive than ELISA, as the endpoint was two to four fold higher with the former technique. Although there was great individual variation, the antibody titres found can be considered high, reaching up to 1:32,000 with ELISA and 1:64,000 with IHC. The results suggest that turbot showing acquired immunity against E. scophthalmi, could develop resistance against new infections.
Subject(s)
Antibodies, Protozoan/blood , Enzyme-Linked Immunosorbent Assay/methods , Eukaryota/immunology , Flatfishes/immunology , Immunohistochemistry/methods , Animals , Aquaculture/methods , Flatfishes/parasitologyABSTRACT
Cryptosporidium scophthalmi n. sp. is described from the turbot Scophthalmus maximus L., sampled from different farms on the coast of NW Spain. The parasite was found mainly in the intestinal epithelium and very seldom in the stomach. Oocysts were almost spherical, with 4 naked sporozoites and a residuum, and measured 3.7-5.03 x 3.03-4.69 microm (mean 4.44 x 3.91) (shape index 1.05-1.34, mean 1.14). Sporulation was endogenous, as fully sporulated oocysts were found within the intestinal epithelium, lumen and faeces. Merogonial and gamogonial stages were in the typical extracytoplasmic position, whereas sporogonial stages were deep within the epithelium. Oocysts and other stages of C. scophthalmi comply with most of the diagnostic features of the genus Cryptosporidium, but differ from all hitherto described species. Ultrastructural features, including the characteristic feeding organelle, were mainly comparable with those of other Cryptosporidium species. Mitochondria were frequently observed in sporozoites. Infection prevalence was very variable, and juvenile fish were most frequently and intensively parasitised. External clinical signs were not detected, although some fish showed intestinal distension at necropsy. The marked histopathological damage occurring in severe infection includes distension of epithelial cells by large vacuoles, containing clusters of oocysts, and can lead to sloughing of epithelial cell remnants and oocysts or even detachment of intestinal mucosa. An inflammatory reaction involving leucocyte infiltration was sometimes observed.
Subject(s)
Cryptosporidium/classification , Cryptosporidium/ultrastructure , Fish Diseases/pathology , Fish Diseases/parasitology , Flatfishes , Analysis of Variance , Animals , Aquaculture , Atlantic Ocean , Cryptosporidium/genetics , Histological Techniques , Intestinal Mucosa/parasitology , Intestinal Mucosa/pathology , Microscopy, Electron, Transmission , Oocysts/cytology , Spain , Species SpecificityABSTRACT
Type I (insulin-dependent) diabetes mellitus is a heterogeneous disease with major subdivisions termed Type 1A (immune-mediated) and Type 1B. Immune-mediated diabetes is also heterogeneous with "monogenic", oligogenic, and polygenic forms present in humans and in animal models. Single-gene mutations of two transcription factors have been recently identified in rare syndromes of autoimmunity with type 1A diabetes: autoimmune polyendocrine syndrome type 1 (APS-1) and X-linked polyendocrinopathy, immune dysfunction and diarrhoea (XPID). For more common forms of diabetes, susceptibility loci within the major histocompatibility complex and at the insulin locus have been identified. Both DQ(*) and DR* alleles provide susceptibility and certain alleles dominant protection. In the Diabetes Autoimmunity Study of the Young approximately 50 % of the siblings studied with the highest-risk HLA genotype develop anti-islet autoantibodies by age 3. Insulin could be a crucial autoantigen related to genetic susceptibility. The crystal structure of the high-risk allele, HLA-DQ8, complexed with an insulin peptide has just been reported. Insulin production by macrophage-dendritic cells within the thymus and lymphoid organs could underlie insulin gene polymorphisms influencing the risk of diabetes. Genome-wide scans for linkage in animal models and in humans have not conclusively identified other susceptibility genes though many loci have been implicated. We favour the hypothesis that HLA is a major determinant of susceptibility in animal models and in most families, and that the search for diabetogenes should concentrate on unique families to decrease heterogeneity and favour the eventual discovery of genes influencing risk.
Subject(s)
Autoimmune Diseases/genetics , Autoimmunity/genetics , Chromosome Mapping , Diabetes Mellitus, Type 1/genetics , Diabetes Mellitus, Type 1/immunology , Animals , HLA Antigens/genetics , Humans , Major Histocompatibility ComplexABSTRACT
A new Myxozoa species causing enteritis and death in cultured turbot, Scophthalmus maximus, is described at light and electron microscope levels. In addition, small subunit ribosomal RNA gene sequences (SSU rDNA) from the new species and from similar myxozoans were obtained and used for phylogenetic inference, as complementary criteria to resolve its taxonomic classification. The new parasite is closely related to Myxidium leei, another enteric histozoic species from marine fish. However, the ascription of M. leei to the genus Myxidium was based on weak morphological evidence and is not supported by our rDNA data analysis. A close relationship with Zschokkella, the other morphologically related myxozoan genus is also not supported. The combined morphological and molecular study results in the establishment of the new genus Enteromyxum to accommodate the new species E. scophthalmi, and the former M. leei, which is transferred to the new genus as Enteromyxum leei (Diamant, Lom & Dyková 1994) n. comb. This genus of marine, histozoic and enteric myxozoans includes significant parasite species for marine finfish culture.
Subject(s)
Eukaryota/genetics , Eukaryota/isolation & purification , Flatfishes/parasitology , Intestines/parasitology , Animals , DNA, Ribosomal/genetics , Eukaryota/classification , Eukaryota/ultrastructure , Fish Diseases/parasitology , Host-Parasite Interactions , Intestinal Diseases, Parasitic/veterinary , Intestines/ultrastructure , Phylogeny , Protozoan Infections/parasitology , Sequence Analysis, DNA , Species SpecificityABSTRACT
Various liquid chromatographic (LC) techniques for analyzing avermectin (Abamectin) were compared after extraction of residues from citrus fruit samples by matrix solid-phase dispersion (MSPD). LC with UV and fluorescence detection were used as also was LC coupled to the mass spectrometer by an electrospray interface. The results obtained by the three methods were compared in terms of sensitivity and selectivity. The combination of MSPD extraction and LC with fluorescence detection have made it possible to quantify 0.5 microg kg(-1) of Abamectin in 0.5 g of orange sample, with an overall average recovery of 94%. The procedure provides a simple and sensitive method for monitoring Abamectin residues in citrus fruit at the levels required by legislation.
Subject(s)
Chromatography, Liquid/methods , Citrus/chemistry , Drug Residues/analysis , Ivermectin/analysis , Ivermectin/analogs & derivatives , Sensitivity and Specificity , Spectrometry, Fluorescence , Spectrometry, Mass, Electrospray Ionization , Spectrophotometry, UltravioletABSTRACT
AIMS: To determine the risk, hazard rate and factors affecting progression to diabetes in monozygotic twins of patients with Type I (insulin-dependent) diabetes mellitus. METHODS: Prospective analysis was done of two cohorts of non-diabetic monozygotic twins of patients with Type I diabetes from Great Britain (n = 134) and the United States (n = 53). RESULTS: The diabetes-free survival analysis was similar between both cohorts (p = 0.6). The combined survival analysis (n = 187, median follow-up = 17.7 years, range = 0.01-57) at 40 years of discordance estimated a 39% probability of diabetes for the initially discordant twin. Survival analysis with left truncation of data estimated that probability to be 50%. For twins who became concordant (n = 47), the median discordance time was 4.2 years (range 0.4 to 39), exceeding 15 years in 23.4%. Twins of probands diagnosed at 24 years of age or younger had a 38% probability of diabetes by 30 years of discordance, compared with 6% for twins of probands diagnosed after 24 years of age (p = 0.004). The twins of probands diagnosed before 15 years of age had the highest diabetes hazard rate in the first discordance year, decreasing thereafter. By survival analysis, diabetes risk was higher in twins who were heterozygous for DR3-DQ2 and DR4-DQ8 than in twins with neither DR3-DQ2 nor DR4-DQ8 (p < 0.05). CONCLUSION/INTERPRETATION: Monozygotic twins of patients with Type I diabetes from two different countries had similar rates of progression to diabetes. Whereas most twins did not develop diabetes, 25% of the twins who progressed did so after more than 14 years of discordance. An age-related heterogeneity was observed, with higher progression to diabetes for twins of patients diagnosed at a younger age.