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The Ikaros family transcription factor Aiolos is important for B cell function, since B cells of Aiolos-null mutant mice exhibit an activated phenotype, enhanced B-cell receptor (BCR) signalling response and develop a systemic lupus erythematosus (SLE) type autoimmune disease. Aiolos has also been reported to interact with anti-apoptotic Bcl-2 and Bcl-x(L) in T cells, but whether Aiolos regulates cell death has not been studied in B cells. Here we show that the disruption of Aiolos in the DT40 B cell line induces a cell death sensitive phenotype, as the Aiolos(-/-) cells are more prone to apoptosis by nutritional stress, BCR cross-linking, UV- or gamma-irradiation. Furthermore, the Aiolos(-/-) cells have defective Ig gene conversion providing evidence that Aiolos is needed for the somatic diversification of the BCR repertoire. The re-expression of DNA-binding isoform Aio-1 was able to restore the gene conversion defect of the Aiolos-deficient cells, whereas the introduction of dominant negative isofom Aio-2 had no effect on gene conversion, thus demonstrating the functional importance of alternative splicing within Ikaros family. Although the Aiolos(-/-) cells exhibit reduced expression of activation-induced cytidine deaminase (AID), ectopic AID overexpression did not restore the gene conversion defect in the Aiolos(-/-) cells. Our findings indicate that Aiolos may regulate gene conversion in an AID independent manner.

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Parasite life-cycles present intriguing model systems to study divergence in resource use and ecology between parasite taxa. In ecologically similar taxa, consistent selective forces may lead to convergence of life-history traits, but resource overlap and similarity of life-cycles may also promote divergence between the taxa in (1) use of host species or (2) specific niche within a host. We studied the life-history characteristics of 2 sympatric species of Diplostomum parasites, D. spathaceum and D. gasterostei, concentrating particularly on differences in intermediate host use and characteristics of the infective stages between the species. This group of trematodes is a notoriously difficult challenge for morphological taxonomy and therefore any information on the ecology of these species can also be helpful in resolving their taxonomy. We observed that these species indeed had diverged as they used mainly different snail and fish species as intermediate hosts and in controlled experiments infected different regions of the eye (lens and vitreous body) of a novel fish host. Interestingly, cercarial characteristics (activity and life-span) were similar between the species and the species were difficult to separate at the cercarial stage unless one observes their swimming behaviour. The release of cercaria from the snail hosts was higher in D. spathaceum, but when cercarial numbers were proportioned to the volume of the snail host, the production was higher in D. gasterostei suggesting differences in the rate of snail host exploitation between the parasite species. These results corroborate the prediction that closely related parasite taxa which are competing for the same resources should have diverged in their life-history characteristics and host use.

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CONTEXT: Early childhood introduction of nutritional habits aimed at atherosclerosis prevention is compatible with normal growth, but its effect on neurological development is unknown. OBJECTIVE: To analyze how parental counseling aimed at keeping children's diets low in saturated fat and cholesterol influences neurodevelopment during the first 5 years of life. DESIGN: Randomized controlled trial conducted between February 1990 and November 1996. SETTING: Outpatient clinic of a university department in Turku, Finland. PARTICIPANTS: A total of 1062 seven-month-old infants and their parents, recruited at well-baby clinics between 1990 and 1992. At age 5 years, 496 children still living in the city of Turku were available to participate in neurodevelopmental testing. INTERVENTION: Participants were randomly assigned to receive individualized counseling aimed at limiting the child's fat intake to 30% to 35% of daily energy, with a saturated:monounsaturated:polyunsaturated fatty acid ratio of 1:1:1 and a cholesterol intake of less than 200 mg/d (n = 540) or usual health education (control group, n = 522). MAIN OUTCOME MEASURES: Nutrient intake, serum lipid concentrations, and neurological development at 5 years, among children in the intervention vs control groups. RESULTS: Absolute and relative intakes of fat, saturated fatty acids, and cholesterol among children in the intervention group were markedly less than the respective values of control children. Mean (SD) percentages of daily energy at age 5 years for the intervention vs control groups were as follows: for total fat, 30.6% (4.5%) vs 33.4% (4.4%) (P<. 001); and for saturated fat, 11.7% (2.3%) vs 14.5% (2.4%) (P<.001). Mean intakes of cholesterol were 164.2 mg (60.1 mg) and 192.5 mg (71. 9 mg) (P<.001) for the intervention and control groups, respectively. Serum cholesterol concentrations were continuously 3% to 5% lower in children in the intervention group than in children in the control group. At age 5 years, mean (SD) serum cholesterol concentration of the intervention group was 4.27 (0.63) mmol/L (165 [24] mg/dL) and of the control group, 4.41 (0.74) mmol/L (170 [29] mg/dL) (P =.04). Neurological development of children in the intervention group was at least as good as that of children in the control group. Relative risks for children in the intervention group to fail tests of speech and language skills, gross motor functioning plus perception, and visual motor skills were 0.95 (90% confidence interval [CI], 0.60-1.49), 0.95 (90% CI, 0.58-1.55), and 0.65 (90% CI, 0.39-1.08), respectively (P =.85,.86, and.16, respectively, vs control children). CONCLUSION: Our data indicate that repeated child-targeted dietary counseling of parents during the first 5 years of a child's life lessens age-associated increases in children's serum cholesterol and is compatible with normal neurological development. JAMA. 2000;284:993-1000

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The objective of this study was to review the published literature on aetiology and treatment of nocturnal enuresis, with the aim of providing a treatment strategy which is easy for the patient and their family to follow. Results from European studies conducted over the last 15 y were included in this review. It can be concluded from the results of these studies that enuresis is the cause and not the result of a psychiatric disorder. However, there is still considerable variation in success rates, from 28 to 90%. It is of vital importance that a caring approach from the doctor and a positive family and patient attitude are present for successful treatment. The first choice of treatment should be the one most acceptable to the family, e.g. alarm, desmopressin and combination treatment.

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OBJECTIVE: Modification of fat intake in childhood may decrease children's future risk for atherosclerosis. Excessive changes in fat intake have been linked with possible growth failure. This study evaluates the effects of a low-saturated fat diet on growth during the first 3 years of life. DESIGN: Half of 1062 healthy infants were randomized at 7 months of age to the intervention group (n = 540) to receive at 1- to 6-month intervals individualized dietary counseling aimed at reducing their exposure to atherosclerosis risk factors. Five hundred twenty-two children served as control children. Growth and serum lipids were measured regularly, and nutrient intakes were analyzed using 3- to 4-day food records at 5- to 12-month intervals. RESULTS: The intervention children consistently consumed slightly less energy than did the control children. The mean fat intake of children in both groups was lower than expected, especially during the first 2 years of life (29.0 [SD, 4.7] percentage of energy intake [E%] and 28.8 [4.1] E% in the intervention and control children, respectively, at 8 months, formula-fed children only). At 13, 24, and 36 months, fat intake in the intervention and control children accounted for 26.2 (6.0) and 27.9 (4.9) E%, 29.9 (5.0) and 32.8 (4.8) E%, and 30.8 (4.9) and 33.2 (4.6) E%, respectively. From 13 to 36 months, the baseline adjusted mean serum cholesterol concentration was lower in the intervention children than the control children (95% confidence interval for the difference between means, -0.27 to -0.12 mmol/L). The true mean of the height of the boys in the intervention group during the trial was at most 0.34 cm more or 0.57 cm less (95% confidence interval), and the weight was at most 0.19 kg more or 0.22 kg less than that of the control boys. The respective values for girls were at most 0.77 cm more or 0.16 cm less and at most 0.42 kg more or 0.04 kg less. The numbers of slim children were similar in both groups. CONCLUSIONS: Fat intake by young children is markedly lower than assumed. A supervised low-saturated fat, low-cholesterol diet has no influence on growth during the first 3 years of life.

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In this cross-sectional prevalence study in 1503 14-year-old Finnish schoolchildren (n = 1503) low back pain was found to be the third most common form of pain interfering with schoolwork or leisure time during the past 12 months. The lifetime cumulative incidence of low back pain was 30% and that of sciatica 1.8%. Of the 417 pupils who had experienced low back pain at some time, 39% had suffered during the past month; 65% recovered in one month from the last pain episode, while 35.2% of those reporting disabling low back pain during the past year were aware of recurrent or continual pain. Thus, 7.8% (n = 107) of the whole population could be classified as "low back pain chronics": 86% of the low back pain chronics had trouble with at least one of the daily activities listed, most commonly with sitting at school. Excluding pain in the extremities or sciatica, girls reported various pains more commonly than boys. Moreover, girls reporting recurrent low back pain had more trouble with their daily activities due to pain than boys (p < 0.001), even though the recovery from the last pain episode took the same time in boys and girls. The pupils who had had sciatica at some time, in addition to recurrent low back pain, had more trouble with the 10 daily activities than others with recurrent low back pain (p = 0.014).

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A study of the prevalence of atopic disorders among 15-16-year-old teenagers was carried out in a coastal urban town in south-western Finland. Altogether, 1712 children were found in that age group, all previously examined by a pediatrician. Each child who had present or previous allergic diseases was invited for a detailed study, a total of 434 (25%) pupils. Of these patients 416 (95.8%) participated in clinical examination and skin testing. The prevalence of atopic diseases was 21% in the studied group; atopic eczema was found in 9.7%, allergic rhinitis in 14% and asthma in 2.5%. Of subjects who had rhinitis, 38% also had atopic eczema, while rhinitis--as the only symptom--was found in 8.8%. Figures obtained from this survey suggest that the prevalence rates of atopic diseases are about the same as found 10 years ago in Finland and they correspond also with other recent reports.

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A retrospective histological analysis has been carried out on 537 cases of transitional-cell bladder carcinoma, followed-up over a period of 9 years. In the first part of the study WHO grade 2 tumours were analysed and a number of independent factors predictive for survival identified. In a multivariate analysis the T category and M/V index (number of mitotic figures/mm2 neoplastic epithelium) were the most important prognostic factors. In a subsequent analysis of the whole series of 537 cases, overall the M/V index was not as important in predicting survival as the stage of the tumour. However, in superficial tumours (Ta-T1) subsequent analysis showed that the M/V index alone could be used to predict survival.

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Thirty-nine 15-year-old children with low-back pain (LBP) and 39 asymptomatic control children were selected from a population of 1,503 children of the same age for a magnetic resonance imaging study of the lumbar spine. Subjects with LBP were matched with control subjects by age, sex, and school class. Disk degeneration (DD) was present in 15 (38%) of the children with LBP and in 10 (26%) of the control subjects. Lumbar degeneration was most frequently associated with disk protrusion and Scheuermann-type changes. Of assessed structural abnormalities (disk protrusion, Scheuermann-type changes, transitional vertebra, and disk space narrowing), only disk protrusion was more common in children of the LBP group than in control subjects. The authors conclude that DD is a frequent finding among children with LBP at the age of 15 years. Asymptomatic (possibly physiologic) DD also is frequently found in children of this age. Whether DD associated with structural changes predisposes to low-back disorders can be confirmed only by means of a longitudinal follow-up study.

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The effect of intranasal desmopressin on primary nocturnal enuresis was investigated in a study divided into 2 parts in which the first part was a randomized, double-blind, placebo-controlled cross-over study of 52 Finnish school children 5 to 13 years old. A variety of approaches had previously been attempted in most children, including water deprivation, night awakenings, enuresis alarm and imipramine, without success. The patients were randomized to 4 periods of 3 weeks each: 2 periods on placebo and 2 periods on 20 micrograms. desmopressin spray. The entire 12-week treatment period was preceded and followed by control periods (without treatment). The number of dry nights, measured as calculated averages per week, increased significantly (p less than 0.01) from 0.6 dry nights during pre-treatment to 4.3 and 4.6 dry nights per week during the 2 desmopressin treatment periods, respectively. The placebo responses were 2.1 and 2.4 dry nights per week, respectively. The second part of the study was an open dose-finding and drug safety study of a further 3 months in duration. The aim was to evaluate the efficacy and tolerance of 20, 30 and 40 micrograms. doses. All 47 patients who relapsed during the post-treatment period in part 1 were included. During this period 53% of the patients responded fully, 19% were intermediate responders and 28% did not respond. As reported in other studies most patients suffered relapse after treatment. During continued treatment for 3 months at doses between 20 and 40 micrograms. desmopressin was well tolerated, had no effect on body weight or blood pressure and did not cause any adverse reactions.

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The usefulness of a combined screening for acute-phase glycoproteins and IgM level in cord sera to denote various intrauterine or delivery-associated disorders was tested in approximately 2,000 consecutive cord sera. Increased glycoprotein level, measured by sensitive and technically simple concanavalin A binding nephelometry, showed a significant association with birth injuries and abnormalities of amniotic fluid, whereas raised IgM levels were linked to maternal genitourinary infections and to cesarean sections performed because of fetal distress. The correlation between these putative risk indices was poor (r = 0.38). Both indices were connected with severe neonatal disease and/or poor outcome of the child, but since such conditions were also otherwise evident at birth, routine screening by these tests was considered unwarranted.

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We prepared monoclonal antibodies against prototype strains of the 15 serovars of Chlamydia trachomatis and identified a subset of reagents that reacted with the major outer membrane protein(s) (MOMPs) of one or more serovars. We then determined the specificities of these anti-MOMP monoclonal antibodies by radioimmunoassay and immunoblot assays against the 15 serovars of C. trachomatis and a C. psittaci strain. We identified 14 different anti-MOMP antibody specificities, including serovar-, several orders of subspecies-, and species-specific determinants. In addition, one antibody reacted with all C. trachomatis serovars and a C. psittaci strain, indicating the presence of a genus-specific epitope on MOMP. Many of the cross-reactions of the subspecies-specific antibodies were similar to those previously reported by use of the microimmunofluorescence technique. We also observed a number of cross-reactions that were unexpected but consistent with data derived by the microimmunofluorescence test. All antibodies, except the genus-specific antibodies, reacted with whole elementary bodies in a radioimmunoassay, suggesting surface exposure of the epitopes. These data confirm and extend previous observations that MOMPs among C. trachomatis serovars are antigenically complex and diverse. In addition, these data indicate that the cross-reaction patterns of some monoclonal antibodies directed against MOMP are similar to those detected by the microimmunofluorescence test and are consistent with the hypothesis that such determinants are contained within MOMPs.

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A panel of 15 monoclonal antibodies was prepared that could distinguish among the 15 serovars of Chlamydia trachomatis. Twelve of these antibodies were specific for a single serovar (A, B, C, D, E, F, G, H, I, K, L1, and L2) and three were specific for two serovars (B/Ba, C/J, and C/L3). Ten of the serovar-specific and two of the bispecific antibodies were shown by immunoblotting to recognize epitopes on the major outer membrane protein. These data provide evidence that such epitopes are closely correlated with and may be partly responsible for the antigenic variations detected by microimmunofluorescence that distinguish the currently recognized serovars. When used in a radioimmunoassay, these antibodies correctly identified the serovar of 17 strains that had been serotyped by the microimmunofluorescence test. In addition, we found that the chlamydial antigen derived from 1.0 cm2 of an infected HeLa cell monolayer was sufficient to allow serotyping with these antibodies. Thus, these monoclonal antibodies may provide a rapid and reliable alternative to mouse immunization and microimmunofluorescence for serotyping of clinical isolates.

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Although urogenital infections with Chlamydia trachomatis are well recognized, less is known about infection at other body sites in adults. Pharyngeal specimens obtained from 706 heterosexual men and 686 women, and rectal specimens obtained from 1223 women who were at risk for chlamydia infection were cultured for C. trachomatis. Urogenital specimens were obtained from all patients. Chlamydia trachomatis was isolated from the pharynx in 3.7% of men and 3.2% of women. Recovery of chlamydiae was not associated with the presence of pharyngeal symptoms, but in women, but not men, it was associated with a history of oral-genital sex. The organism was also recovered from the rectum of 5.2% of the women. Rectal isolation did not correlate with a history of rectal symptoms or rectal sex but did correlate with concurrent genital infection. Infection at these sites may be important in the transmission or persistence of C. trachomatis infections.

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A nucleic acid spot hybridization assay was used to detect Chlamydia trachomatis DNA. The hybridization probes included DNA isolated from elementary bodies of lymphogranuloma venereum (LGV) strains and cloned fragments of both chromosomal and plasmid DNA. The sensitivity of the test was in the range 10 to 100 pg homologous DNA and 10 in vitro infected cells. Cross-reactivity with bacterial DNA was avoided when purified chlamydia-specific DNA fragments were used as probes. C. trachomatis was detectable in most of the clinical specimens with large amounts of infectious particles. Also some isolation-negative specimens gave a positive signal in the test.

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Elementary bodies of lymphogranuloma venereum (LGV) strains of Chlamydia trachomatis contain, in addition to the genomic DNA, a 6.7 kb plasmid. The plasmid from serovar L2 (434-B) was cloned at the BamHI site of pBR327 into Escherichia coli and a restriction cleavage map of this pLGV125 recombinant plasmid determined. All 15 C. trachomatis serovars contained DNA sequences that hybridized with pLGV125. When total DNA from L2 elementary bodies was used as a probe in Southern blotting and spot hybridization, serovars L1, L2 and L3 exhibited significant homology. The detection level of homologous DNA was 100 pg and LGV DNA was detectable in infected cells when total L2 probe was used in the nucleic acid hybridization test. These DNA probes may be useful as investigative and diagnostic reagents for C. trachomatis.

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To study the nature of urogenital involvements in female uro-arthritis 73 consecutive patients with arthritis concomitant with any type of urogenital involvement were examined. The controls were 281 females interviewed only and an additional 83 also gynaecologically examined. A history of cervicitis, salpingitis, dysuria and pyelocystitis/-nephritis occurred significantly more often in patients than in controls. Clinical gynaecological examination revealed cervicitis in 26,8% (19/71) of the patients and 15.7% (13/83) of the controls (p less than 0.05). Aseptic pyuria was definitely more frequent in patients (19/73) than in controls (0/63). The isolation of Chlamydia trachomatis was positive in 14.7% (10/68) of the patients and 3.7% (3/81) of the controls (p less than 0.025). Serological evidence (titre greater than or equal to 64) for chlamydial infection was obtained in 53.4% (39/73) of the patients and 18.2% (14/77) of the controls (p less than 0.00025). The results indicate the importance of urogenital history and findings in females with rheumatic attacks. The most prominent and persistent urogenital involvements were cervicitis, salpingitis, pyuria and dysuria. Chlamydial infection appears in any case to be responsible for part of these involvements (42/73).

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The effect of 20 micrograms. desaminocysteine-D-arginine vasopressin intranasally on childhood nocturnal enuresis was studied in a randomized double-blind cross-over series of 54 children. The wetting was significantly less frequent during the 2, 3-week periods on desaminocysteine-D-arginine vasopressin than during placebo periods, or during periods without any treatment. The effect of desaminocysteine-D-arginine vasopressin was reproducible and the efficacy of desaminocysteine-D-arginine vasopressin depended on the frequency of wetting before treatment. After discontinuation of the short treatment enuresis recurred immediately. No side effects were noted. We conclude that desaminocysteine-D-arginine vasopressin may well be used in the management of childhood enuresis, especially in situations when an immediate effect is desirable.

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The prevalence of cervical Chlamydia trachomatis infection in healthy, symptomless full-term pregnant women (n = 92) was found to be low (1.1%). Chlamydial cervical IgA antibodies, as measured by solid-phase radioimmunoassay (RIA), were found in 5.3%, but amniotic fluid chlamydial RIA IgA antibodies were almost absent. Serum IgG antibodies were measured with indirect immunofluorescence (IF). Of the mothers 9.8% had a titer greater than or equal to 1:64, correlating closely with the figure of 10.9% for infants' cord-blood IF serology. Finally, a case report is presented. A child born to a Chlamydia trachomatis positive mother developed isolation positive chlamydial pneumonia.

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