ABSTRACT
How far do marine larvae disperse in the ocean? Decades of population genetic studies have revealed generally low levels of genetic structure at large spatial scales (hundreds of kilometres). Yet this result, typically based on discrete sampling designs, does not necessarily imply extensive dispersal. Here, we adopt a continuous sampling strategy along 950 km of coast in the northwestern Mediterranean Sea to address this question in four species. In line with expectations, we observe weak genetic structure at a large spatial scale. Nevertheless, our continuous sampling strategy uncovers a pattern of isolation by distance at small spatial scales (few tens of kilometres) in two species. Individual-based simulations indicate that this signal is an expected signature of restricted dispersal. At the other extreme of the connectivity spectrum, two pairs of individuals that are closely related genetically were found more than 290 km apart, indicating long-distance dispersal. Such a combination of restricted dispersal with rare long-distance dispersal events is supported by a high-resolution biophysical model of larval dispersal in the study area, and we posit that it may be common in marine species. Our results bridge population genetic studies with direct dispersal studies and have implications for the design of marine reserve networks.
Subject(s)
Gene Flow , Genetics, Population , Animals , Humans , Larva/genetics , Mediterranean SeaABSTRACT
The spread of IgG antibodies to cytomegalovirus and Toxoplasma in the blood sera of 323 donors of hemocomponents was studied. Among young males in the northwestern region of Russia three fourths were found to be seropositive to cytomegalovirus and one third, to Toxoplasma. In older ages the proportion of seropositive persons somewhat increased. In donors with blood group O (I) antibodies to cytomegalovirus occurred almost twice as often (91%) as in donors with blood group AB (IV) (47%). Among donors with blood group AB (IV) the proportion of persons seropositive to Toxoplasma (54%) was twice as great as that among donors with blood group O (I) (27%).
Subject(s)
Antibodies, Protozoan/blood , Antibodies, Viral/blood , Blood Donors , Cytomegalovirus/immunology , Toxoplasma/immunology , ABO Blood-Group System/immunology , Adolescent , Adult , Aging/immunology , Animals , Blood Donors/statistics & numerical data , Humans , Immunoglobulin G/blood , Male , Russia , Urban Population/statistics & numerical dataSubject(s)
Diabetes Mellitus, Type 1/epidemiology , Adolescent , Adult , Child , Child, Preschool , Female , Humans , Incidence , Infant , Infant, Newborn , MaleABSTRACT
Correlation between the state of vitamin metabolism and the impairments in carbohydrate, lipid and protein metabolism was studied in 35 children of 9-13 years of age with diabetes mellitus of various severity standing for up to 7 years. Deterioration of riboflavin metabolism in insulin-dependent diabetes mellitus, expressed as an increase of the vitamin excretion with urine, was augmented with prolongation of the disease duration; the deterioration was sometimes related to the value of glycemia and glucosuria, being the indicative symptom of the disease. In spite of some limitations in validity of experiments related to insufficient number of children in some groups, a decrease in excretion of 1-methyl nicotinamide with urine was detected in all the children with the comatose state, in acidoketosis and glucosuria (above 20 g/day), whereas normal content of nicotinamide coenzymes was found in erythrocytes. Deficiency in vitamins B1, B6 and C was observed more often (5-100%) in children with elevated content of cholesterol as compared with 7-67% of children exhibiting normal level of cholesterol. Optimization of vitamins B and C consumption in children as well as use of any means for correction of these vitamins deficiency are discussed.
Subject(s)
Diabetes Mellitus, Type 1/metabolism , Vitamins/metabolism , Adolescent , Ascorbic Acid/metabolism , Child , Cholesterol/blood , Diabetic Ketoacidosis/metabolism , Glycosuria/metabolism , Humans , Niacin/metabolism , Pyridoxine/metabolism , Riboflavin/metabolism , Severity of Illness Index , Thiamine/metabolism , Time FactorsABSTRACT
A vitamin status was studied in 32 children of both sexes at the age of 9-15 years with insulin-dependent diabetes mellitus within 2-3 years. The adequate consumption of all the vitamins studied was found only in two children. Polyhypovitaminosis was detected in 19% of these children. Deterioration of riboflavin metabolism observed was manifest, as a decrease in the vitamin content in tissues in line with an increase in its excretion with urine. As a result of this impairment metabolism of vitamins B6 and PP was disturbed with development of these vitamins secondary deficiency of the non-alimentary type. Obligatory correction of the water soluble vitamin deficiency in the patients with diabetes mellitus is discussed.
Subject(s)
Diabetes Mellitus, Type 1/physiopathology , Vitamin B Complex/blood , Vitamin B Deficiency/complications , Adolescent , Child , Diabetes Mellitus, Type 1/complications , Female , Humans , Male , Vitamin B Complex/metabolism , Vitamin B Complex/urineABSTRACT
Glutamic acid decarboxylase (GAD) is considered as target antigen in pancreatic beta cell autoimmunity. Two isoforms of GAD (islet and brain GAD) were detected recently. In circulation of approximately 80% of recently detected patients with insulin-dependent diabetes mellitus (IDDM) autoantibodies to brain GAD (bGAD) have been demonstrated. To detect autoantibodies to bGAD blood sera of 48 children aged 1 to 14, 36 of these with newly diagnosed IDDM, 2 with impaired glucose tolerance (IGT), 10 healthy controls, were tested. Indirect immunofluorescent staining of rat cerebellum cryoslices was carried out. The results were assessed using fluorescent microscopy and processed by statistical methods. Autoantibodies to bGAD were found in 30 out of 36 patients with IDDM: 83.3 +/- 12.4% (p = 95%), in 1 with IGT, and in none of controls. The fact that all controls were antibody-negative proves a high specificity of this immunological marker of IDDM. Family history or a younger age by the moment of diabetes onset were conductive to a higher prevalence of autoantibodies to GAD, each of these factors being unrelated to the other.
Subject(s)
Autoantibodies/blood , Brain/enzymology , Diabetes Mellitus, Type 1/immunology , Glutamate Decarboxylase/immunology , Adolescent , Animals , Biomarkers/blood , Child , Child, Preschool , Female , Glucose Intolerance/blood , Humans , Infant , Male , Microscopy, Fluorescence , Rats , Rats, WistarABSTRACT
Vitamin-deficient children suffering from diabetes mellitus received milk dishes and drinks enriched with vitamin-rich premixes produced in Austria (Roche) for 2 weeks. The diet efficacy was evaluated by the values of thiamine, riboflavin, 4-pyridoxic acid, 1-methylnicotinamide and xanthurenic acid urinary excretion, blood levels of free and total riboflavin, nicotinamide and pyridoxic coenzymes, transketolase activity measured before and after the diet treatment. The latter resulted in a marked improvement in the levels of vitamins B1, B2, B6, PP and C, prevented the spring fall in vitamin supply. In view of incomplete normalization of the children's vitamin status after the two-week diet it is recommended to use the vitamin-enriched food and drinks for longer time or under a continuous regimen.