Plasma immunoglobulin concentrations in an African (Gambian) community in relation to season, malaria and other infections and pregnancy

IgG, IgA, IgM and IgD concentrations in plasma were measured at three surveys of a rural Gambian community made over 13 months. 3523 samples were analysed. The pattern of change with age of mean levels of each immunoglobulin class was similar at each survey, although IgM levels were highest in the survey made at the end of the wet season. Immunoglobulin levels in the same individual were found to be relatively stable in adults over the study period. Only minor correlations were found between the levels of different immunoglobulin classes in plasma from the same individual.Malarial parasitaemia was associated with increased mean IgG levels in age groups up to 20 years but with increased IgM levels only in the first 2 years of life. Plasma which contained precipitating antibodies to malarial antigens showed higher mean levels of IgG and IgM in most age groups. In association with splenomegaly mean IgG levels were increased throughout childhood while mean IgM levels were elevated only in the first 2 years. No consistent relationship between malaria and mean levels of IgA and IgD were noted. The only relationship found between haemoglobin concentration and immunoglobulin levels was a small negative correlation in respect of IgM.Clinical infection, other than malaria, was associated with increased mean levels of IgG and IgA in all age groups and of IgM in young children. Lower levels of IgG, IgA and IgM occurred in pregnancy; IgG levels seemed to fall progressively as pregnancy advanced. At certain ages mean levels of IgM and IgD were higher in females than males.     

Serum immunoglobulin levels in healthy children and adults

Serum levels of IgM, IgG and IgA were determined in 270 healthy children, 4–12 years old, and in thirty healthy adults by the radial immunodiffusion method of Mancini. There were nine 1-year age groups of thirty children each (fifteen boys and fifteen girls); the adult group consisted of fifteen males and fifteen females.

The difference in values between adults and children was statistically significant. The IgG and IgA concentrations showed a gradual rise with increasing age; the IgM concentration remained constant at a distinctly lower level than that in adults. The IgA level was about the same in both sexes. Girls had significantly higher IgM and IgG levels than boys. A consistent seasonal influence on the three serum immunoglobulin concentrations could not be demonstrated. A very wide variation in serum levels of each immunoglobulin in each age group was found. Very low values were by no means exceptional. The consequence of this finding for the diagnosis of immunological incompetency is discussed.

     

Measurement of immunoglobulin concentrations in the feces of healthy dogs

Selective immunoglobulin A (IgA) deficiency is the most common primary immunodeficiency in humans and may be associated with chronic gastrointestinal disease. This observation has led to the suggestion that the high susceptibility of German shepherd dogs (GSD) to chronic enteropathies is related to a deficiency in mucosal IgA production. Relative deficiencies of IgA has been reported in the serum, saliva, tears, and feces of GSD both with and without alimentary disease; however, the findings of different studies are not consistent. The aim of this study was to confirm whether a relative deficiency of IgA exists in the feces of GSD. Feces were collected from healthy GSD (n = 209), Labrador retrievers (n = 96), beagles (n = 19), and miniature schnauzers (n = 32). Fecal IgA, IgM, and IgG were measured by capture enzyme-linked immunosorbent assays. Fecal IgG concentrations in the four breed groups were not significantly different. IgA concentrations were significantly greater in miniature schnauzers than in GSD (P = 0.0003) and Labradors (P = 0.0004) but not significantly different from those in beagles. IgM concentrations were significantly greater in miniature schnauzers than in GSD (P < 0.0001), Labradors (P < 0.0001), and beagles (P = 0.0098). These findings do not support the hypothesis that GSD have a relative deficiency in fecal IgA. The differences in immunoglobulin concentrations measured from a single defecation, between individuals of the same breed and between breeds, as well as the lack of an internal control molecule, make the determination of a normal reference range for all dogs impossible. Therefore, the usefulness of fecal immunoglobulin quantification for the assessment of intestinal immunoglobulin secretion in dogs is limited.     

正常新生儿出生时的生长抑素和神经紧张素水平

采用放射免疫技术，测定了14例正常足月新生儿及其母亲血中生长抑素和神经紧张素浓度，发现脐动脉生长抑素和神经紧张素浓度明显高于脐静脉浓度（P均＜0．01），二者均明显高于分娩后即刻母亲静脉血中相应的激素浓度（P均＜0．01）；脐动脉pH与脐动脉生长抑素和神经紧张素浓度存在一种负相关关系（P均＜0．01）。提示脐血中高浓度的生长抑素和神经紧张素极可能是胎儿源性的，且可能与分娩引起的胎儿应激有关。     

Plasma total homocysteine concentrations in adults with growth hormone (GH) deficiency: effects of GH replacement

Growth hormone (GH) deficiency is associated with increased cardiovascular morbidity and mortality. GH treatment improves the profile of many cardiovascular risk markers in individuals with GH deficiency (GHD). The aim of the present was to assess whether GH replacement may decrease plasma total homocysteine, an independent cardiovascular risk factor, thus potentially contributing to benefits of GH replacement in adult subjects with GHD. Twenty-five patients (17 female, 8 male), mean age 39-years, with GHD were studied. GH status had been determined by an insulin tolerance test and/or arginine stimulation test. After an overnight fast, plasma insulin, IGF-1, total homocysteine (Hcy), free thyroxine (FT4), creatinine, vitamin B12, and folate were measured at baseline (V1), 3 months (V2) and then at 6 months (V3) on GH treatment. The data were analysed by hierarchical statistical models, univariate and multivariate correlation. GH treatment resulted in an increase in IGF-1 (p<0.001, p<0.001), and insulin (p=0.068, p<0.001), at each visit, respectively. Hcy levels increased from V1 to V2 (7.7+/-0.53 to 9.15+/-0.45 micromol/L; p=0.051), but this was followed by a decline at V3 (to 8.8+/-0.59), so that the overall change of Hcy levels from V1 to V3, once individuals had achieved 'adequate' GH replacement, was no longer significantly different (p=0.090). When separated by gender, at 6 months (V3) there was a small, but significant increase in Hcy in men (p=0.028), but not in women (p=0.58). There was no significant change in B12, folate, free T4 or creatinine levels. Univariate analysis revealed that only B12 and folate showed significant negative relationships with Hcy (B12: parameter= -0.013, p<0.001; folate: parameter=-1.31, p<0.001), but not between Hcy and IGF-1 (p=0.18). In a multiple variable model, both B12 and folate remained significantly negatively associated with plasma total homocysteine (p=0.018; p<0.001, respectively). In this observational study normalisation of IGF-1 levels in adult subjects with growth hormone deficiency was not associated with a fall in total homocysteine. Before firm conclusions can be drawn about the contribution of changes in plasma homocysteine concentrations to cardiovascular prognosis in adult GHD patients receiving GH replacement, further controlled studies are required.     

Validation of the Detroit area study discrimination scale in a community sample of older African American adults: The Pittsburgh healthy heart project

This study examined the construct validity of the Detroit Area Study Discrimination Questionnaire (DAS-DQ) in 49 healthy African American adults, with respect to its association with global measures and daily experiences of psychological demand. Daily experiences of psychological demand were obtained using ecological momentary assessment (EMA) methods. Everyday Mistreatment, as measured by the DAS-DQ, was significantly related to global reports of perceived stress and depression but was unrelated to measures of hostility and social desirability. Everyday Mistreatment was significantly related to average EMA score measures of Negative Affect and Social Conflict but was unrelated to daily experiences of Task Demand or Decisional Control. Negative Affect mediated the relation between Everyday Mistreatment and global reports of perceived stress. In contrast, Lifetime History of Discrimination, as measured by the DAS-DQ, was unrelated to global measures or daily experiences of stress. Thus, this study lends support to the construct validity of the DAS-DQ.     

Relationships of soluble APO-1 (Fas/CD95) concentrations, obesity, and serum lipid parameters in healthy adults

To investigate the relationships of apoptosis with obesity and lipid parameters, we measured serum soluble APO-1 (sAPO-1) concentrations, body mass index (BMI), and serum lipid profiles in 176 healthy adults. Serum sAPO-1 levels were measured by enzyme immunoassay. There were no significant differences in mean sAPO-1 concentrations between men and women, nor between subjects with and without obesity. However, women with high-density lipoprotein cholesterol (HDL-C) <50.2 mg/dl exhibited significantly higher sAPO-1 concentrations than those with HDL-C >50.2 mg/dl (ie, 45.6 +/- 10.4 pg/ml vs 31.5 +/- 11.3 pg/ml, p <0.05). Serum sAPO-1 concentrations averaged 46.8 +/- 10.7 pg/ml in women with serum triglyceride >137.4 mg/dl, which was significantly above the mean value (32.6 +/- 12.0 pg/ml, p <0.05) in those with serum triglyceride <137.4 mg/dl. Men with elevated sAPO-1 concentrations showed significantly higher waist-to-hip ratio (WHR) and total body fat (TBF) compared to those with diminished sAPO-1 levels, although no differences were noted in mean values of lipid profiles between the 2 groups of men. Serum sAPO-1 concentrations correlated significantly with HDL-C (r = - 0.41, p <0.05) and triglyceride (r = 0.35, p <0.05) in women and WHR (r = 0.25, p <0.05) and TBF (r = 0.21, p <0.05) in men. In conclusion, serum sAPO-1 appears to have an important relationship to serum lipid levels and body adiposity in healthy adults.     

Western Blot analysis of immunoglobulin G antibodies to pneumococcal protein antigens in healthy adults

Using the Western Blot technique, sera from apparently healthy individuals were shown to contain antibodies against pneumococcal protein antigens of different molecular weights. A remarkable correlation was found to exist between the number of protein bands stained and the level of antibodies to type-specific carbohydrate antigens and C-polysaccharide. The findings suggest that the presence of antibodies against protein antigens reflects past infection with pneumococci.     

Lexical effects and lexical properties associated with National Adult Reading Test (NART) stimuli in healthy young adults and healthy elderly adults

Fifty healthy younger adults and 45 healthy elderly adults performed a speeded lexical decision task (LDT). Stimuli consisted of 57 National Adult Reading Test (NART) words (the NART consists of “irregular” words that violate standard spelling-to-sound correspondence rules) and 57 pronounceable pseudowords (e.g., blant). Both groups displayed statistically equivalent lexicality (PW-W) effects, and error rates were lower in elderly adults. With groups equated on vocabulary ability, lexicality effects remained the same and error rates did not differ across either group. Correlational analyses confirmed the role played by word frequency and word familiarity in latencies to NART stimuli. Results are discussed regarding the importance of obtaining speeded latency measures for age-related word recognition comparisons. © 1998 John Wiley & Sons, Inc. J Clin Psychol 54: 577–584, 1998.     

Absence of Helicobacter pylori within the oral cavities of members of a healthy South African community

Our study aimed to evaluate the oral cavity as a reservoir from where Helicobacter pylori may be transmitted. Histology and PCR amplification were performed. Eighty-four percent of the stomach biopsies tested positive; however, H. pylori was not detected in dental samples, indicating the absence of H. pylori within the oral cavity.     

Heritability of stature in a West African population

Heritability of stature in a West African popuIation is calculated from longitudinal data collected over 26 years. Statistical and analytical difficulties encountered in the study include those due to variation in stature with age, sex, recording and measuring, variation in number of offspring, variation in number of spouses, and heterogeneity of within-sibship variances. The structure of the population allows a half-sib analysis which is particularly useful in interpretation of the intrafamilial correlations and regressions. The heritability estimate of 0.6 appears lower than that from studies in European populations, The environmental contribution t o the stature variance is pronounced, but is not unexpected in the light of the rigours of the traditional way of life in West African surroundings. Acknowledgement is gratefully made to Miss R. M. Holliday for computational assistance.     

Verbal deficits in Klinefelter (XXY) adults living in the community

Forty-two adult males--10 with Klinefelter's syndrome (karyotype XXY), 17 with normal sex chromosome karyotype (XY) but with physical signs of hypogonadism, and 15 presumed to be normal both chromosomally and hormonally--completed tests of Verbal and Nonverbal ability. It was predicted: a) that the XXY group would perform more poorly than the other two groups on tests of Verbal ability, and b) that the XY, hypogonadal group would perform more poorly than the others on tests of Non-verbal ability. The first hypothesis was supported. However, in spite of measurable verbal deficits, the XXY men (whose parents were more highly educated than those of the other two groups) did not appear to be underachievers. Rather, they were, in general, as well educated, as likely to be employed, and of socioeconomic status equivalent to that of the other men in the study. These findings are discussed briefly in terms of implications for early childhood education and genetic counselling. The second hypothesis was not supported: this is attributed to presumed heterogeneity of etiology of hypogonadism in the XY, hypogonadal group.     

Maternal immunoglobulin allotype (Gm and Km) and neonatal group B streptococcal infection

Gm and Km(1) allotypes in 37 mothers of neonates with severe Group B streptococcal (GBS) infection were compared with 115 mothers of non-infected infants, 36 of whom were known to be colonized with GBS. Deficits in G1m(1) and Km(1), and an increased incidence of G2m(23), were found in mothers of infected infants. Km(1) was associated mainly with the phenotype Gm(1, (2), 3, 17; 23; 5, 10, 11, 21) in mothers of infected infants while being uniformly distributed in mothers of non-infected infants. This study would seem, therefore, to support reports of Gm and Km(1) allotype involvement in maternal response to GBS infection and immunity in the new-born.     

Herpes simplex virus-specific serum immunoglobulin a: detection in patients with primary or recurrent herpes infections and in healthy adults.

A sensitive radioimmunoassay was used to determine levels of herpes simplex virus (HSV)-specific immunoglobulin A (IgA) in serial serum samples drawn from patients with primary HSV infections and from persons with recurrent HSV infections, and in single samples from 90 healthy adults. Significantly rising HSV IgA titers were detected in patients with primary infections, whereas those with recurrent infections had nonfluctuating titers. Sera of IgG-seropositive healthy adults were all positive for HSV-specific IgA without special pretreatment.