Association between larger thymic size and higher thymic output in human immunodeficiency virus-infected patients receiving highly active antiretroviral therapy

To examine the impact of thymic size on immune recovery in patients with human immunodeficiency virus (HIV) infection, the thymus was visualized, using computed tomographic scans, in 25 HIV-infected patients who had received highly active antiretroviral therapy (HAART) for 6-18 months and had levels of viremia <500 copies/mL. For comparison, 10 control subjects were included in the study. Total and naive CD4+ cell counts were determined by flow cytometry. To determine thymic output, the number of CD4+ cells containing T cell receptor excision circles (TRECs) was measured. Qualitative immune recovery was evaluated by determination of CD4+ T cell receptor repertoire in 19 of the HIV-infected patients. Larger thymic size was associated with higher CD4+ cell counts (r=0.498; P=.011) and higher CD4+ TREC frequency (r=0.652; P<.001). Furthermore, patients with abundant thymic tissue seemed to have broader immunologic repertoires, compared with patients with minimal thymic tissue (P=.054). These findings suggest that thymopoiesis is ongoing in the adult thymus and contributes to immune reconstitution in HIV-infected patients receiving HAART.     

Characterization of serotonin(4) receptors in adrenocortical aldosterone-producing adenomas: in vivo and in vitro studies

We have previously shown that serotonin (5-HT) stimulates aldosterone secretion from the human adrenal gland through activation of 5-HT(4) receptors. The aim of the present study was to investigate in vivo and in vitro the presence of 5-HT(4) receptors in aldosterone-producing adenomas (aldosteronomas). Eight patients with aldosteronoma received a single oral dose of placebo or cisapride (10 mg). Cisapride administration significantly increased plasma aldosterone within 120 min without any significant change in renin, cortisol, or potassium levels. In two patients, a marked decrease in the plasma aldosterone response to cisapride was observed after surgical removal of the tumor. The effects of 5-HT and selective 5-HT(4) ligands on aldosterone production from aldosteronoma tissues were studied in vitro using a perifusion system technique. 5-HT and the 5-HT(4) receptor agonist cisapride (10(-7) M, 20 min) both stimulated aldosterone secretion from aldosteronoma slices. The 5-HT- and cisapride-evoked aldosterone responses were inhibited by concomitant administration of the specific 5-HT(4) receptor antagonist GR 113808 (10(-7) M, 150 min). PCR amplification revealed the expression of 5-HT(4) receptor mRNA in 13 of 14 aldosteronomas studied. Taken together, these data show that most aldosteronomas, like normal glomerulosa cells, express a functional 5-HT(4) receptor. Our results also suggest that 5-HT, which can be locally released by intratumoral mast cells, may play a role in the pathophysiology of these tumors.     

Levels of genetic diversity vary dramatically between Blastocystis subtypes

Blastocystis is a common single-celled parasite of humans and other animals comprising at least 13 genetically distinct small subunit ribosomal RNA lineages (subtypes (STs)). In this study we investigated intra-subtype genetic diversity and host specificity of two of the most common subtypes in humans, namely ST3 and ST4, by analysing and comparing over 400 complete and partial nuclear SSU-rDNAs and data from multilocus sequence typing (MLST) of the mitochondrion-like organelle (MLO) genome of 132 samples. Inferences from phylogenetic analyses of nuclear SSU-rDNA and concatenated MLST sequences were compatible. Human ST3 infections were restricted to one of four identified MLO clades except where exposure to non-human primates had occurred. This suggests relatively high host specificity within ST3, that human ST3 infections are caused predominantly by human-to-human transmission, and that human strains falling into other clades are almost certainly the result of zoonotic transmission. ST4 from humans belonged almost exclusively to one of two SSU-rDNA clades, and only five MLST sequence types were found among 50 ST4s belonging to Clade 1 (discriminatory index: 0.41) compared to 58 MLST sequence types among 81 ST3s (discriminatory index: 0.99). The remarkable differences in intra-subtype genetic variability suggest that ST4 has a more recent history of colonising humans than ST3. This is congruent with the apparently restricted geographical distribution of ST4 relative to ST3. The implications of this observation are unclear, however, and the population structure and distribution of ST4 should be subject to further scrutiny in view of the fact ST4 is being increasingly linked with intestinal disease.     

Birthweight,Childhood Body Mass Index,Height and Growth,and Risk of Polycystic Ovary Syndrome

IntroductionAdult obesity is linked with polycystic ovary syndrome (PCOS), but the importance of body size at ages before PCOS is diagnosed is unknown.ObjectiveTo investigate associations between a woman''s own birthweight, childhood body mass index (BMI), height and growth patterns in relation to her risk of PCOS.MethodsWe included 65,665 girls from the Copenhagen School Health Records Register, born in the period 1960–1996, with information on birthweight and measured weight and height at the ages of 7–13 years. Overweight was defined using International Obesity Task Force (IOTF) criteria. From the Danish National Patient Register, 606 women aged 15–50 years were identified. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated by Cox regression analysis.ResultsBirthweight was not associated with PCOS. At the age of 7–13 years, girls with overweight had a higher risk of developing PCOS than girls without overweight; HR 2.83 (95% CI 2.34–3.42) at age 7 years and 2.99 (95% CI 2.38–3.76) at age 13 years. Furthermore, girls with overweight at both 7 and 13 years had a higher risk of developing PCOS than girls without overweight or overweight at only one age. Height was positively associated with PCOS risk at all ages. Girls who were persistently tall or changed from tall to average height had a higher risk of developing PCOS than girls with average height growth.ConclusionOverweight and tall stature in childhood are positively associated with PCOS risk, but birthweight is not.     

Individualizing recall intervals in child dental care

Abstract Individualizing and extending recall intervals for children have been recommended in Norway to target resources efficiently. Recall intervals were changed for children aged 3–18 years in Drammen from 1991. Clinical time spent by dentists and dental hygienists, dental health status and length of recall intervals were registered from 1990 to 1993. For the child population, the mean recall interval changed from 12.5 to 13.7 months and the annual time spent per child was reduced by 14% from 1990–91 to 1992–93. Adjusted for the decline in number of new decayed teeth, the reduction in time spent was 11%. Children with intervals of 17 to 20 months had fewer new decayed teeth and their care required less personnel time than other children. For children with new decayed teeth, time spent for dental care was not associated with recall interval, while for children without new decayed teeth, longer recall intervals were associated with shorter time for dental care. The variation in number of decayed teeth and time spent for dental care was substantial at all intervals. Individualizing and extending recall intervals to some extent targeted resources at children with more dental disease. However, in the short run, inequality in dental health persisted. Limited extension of recall intervals did not interrupt the long-term trend toward better dental health in the children and substantial resources were saved in the dental services.     

Urodynamic biofeedback training for children with bladder-sphincter dyscoordination during voiding

Neurologically normal children with recurrent urinary tract infections (UTIs), night- and daytime wetting, and urge and painful voiding may have staccato voiding due to pelvic floor contractions. The immediate effect of non-invasive urodynamic biofeedback (BF) therapy was assessed using a historical follow-up study in 31 children aged 5–15 years suffering from urodynamically proven overactive urethra during voiding. A long-term follow-up study was performed to investigate whether improvement was maintained. Twenty-four children (77.5%) benefited from the treatment. Of these 16 (51.5%) were cured, while 8 (26%) had a pronounced reduction in their symptoms. Although the flow was normalized in 17 (55%) and nearly normalized in 7 (22.5%), there was no significant correlation between subjective and objective criteria of improvement. Similarly, no relationship was found between the initial urodynamic characteristics and the treatment outcome. During a mean follow-up time of 4 years (range: 1–7.5 years) two of the initially cured patients relapsed. They were recured with a refresher course. Three had had a single or a few episodes of cystitis in the course of several years. Of the patients with pronounced reduction in their symptoms, three relapsed. A refresher course was attempted in two patients; one was successful. It can thus be concluded that BF is an effective way of treating this disturbance and the beneficial effect is to a wide degree maintained.     

Dental caries in schoolchildren in some Danish communities with and without school dental service

ABSTRACT The purpose of the investigation was to compare the caries prevalence (DMF-T) among 762 7th grade children, of whom one-hall had received regular school dental care throughout their school attendance and the other half had never received school dental care. The children were grouped according to social status in order to see if there was any difference in the caries prevalence between the social groups. The caries prevalence in children both with and without school dental service was high, 9.5 DMF-T and 10.5 DMF-T. The prevalence of untreated caries and secondary caries was lowest in the group with school dental service.