Transcriptome analysis reveals dysregulation of genes involved in oxidative phosphorylation in a murine model of retinopathy of prematurity

BACKGROUND

Retinal gene expression pattern is severely altered after exposition to hyperoxia in mice with oxygen-induced retinopathy (OIR), a common model of retinopathy of prematurity. Gene ontology and signaling pathway analyses may add new insights into a better understanding of the pathogenesis of this disease.

METHODS

Seven-day-old C57BL/6J mice (n = 60) were exposed to 75% oxygen for 5 days and then recovered in room air. The controls (n = 60) were kept in the normoxic conditions. Retinas were harvested immediately following hyperoxia, during the phase of maximal neovascularization, and at the time of neovascularization regression. The retinal RNA samples were evaluated for gene expression using mouse gene expression microarrays. DAVID annotation tools were used for gene ontology and pathway analyses.

RESULTS

The most significantly enriched signaling pathways during the neovascularization phase of OIR were: focal adhesion; ECM-receptor interaction; PI3K-Akt; oxidative phosphorylation; and Alzheimer's, Parkinson's and Huntington's disease signaling pathways. Genes involved in apoptosis, cell proliferation, cell differentiation, and immune responses were associated with neovascularization regression.

CONCLUSIONS

Performed analyses revealed the possible involvement of various signaling pathways in OIR pathomechanism, mostly specific to the OIR phase. Dysregulation of genes involved in oxidative phosphorylation may have an impact on neovascularization development.

Short- and long-term impact of hyperoxia on the blood and retinal cells' transcriptome in a mouse model of oxygen-induced retinopathy

BACKGROUND

We aimed to identify global blood and retinal gene expression patterns in murine oxygen-induced retinopathy (OIR), a common model of retinopathy of prematurity, which may allow better understanding of the pathogenesis of this severe ocular prematurity complication and identification of potential blood biomarkers.

METHODS

A total of 120 C57BL/6J mice were randomly divided into an OIR group, in which 7-day-old pups were maintained in 75% oxygen for 5 days, or a control group. RNA was extracted from the whole-blood mononuclear cells and retinal cells on days 12, 17, and 28. Gene expression in the RNA samples was evaluated with mouse gene expression microarrays.

RESULTS

There were 38, 1370 and 111 genes, the expression of which differed between the OIR and control retinas on days 12, 17, and 28, respectively. Gene expression in the blood mononuclear cells was significantly altered only on day 17. Deptor and Nol4 genes showed reduced expression both in the blood and retinal cells on day 17.

CONCLUSION

There are sustained marked changes in the global pattern of gene expression in the OIR mice retinas. An altered expression of Deptor and Nol4 genes in the blood mononuclear cells requires further investigation as they may indicate retinal neovascularization.

Comparative two time-point proteome analysis of the plasma from preterm infants with and without bronchopulmonary dysplasia

Background

In this study, we aimed to analyze differences in plasma protein abundances between infants with and without bronchopulmonary dysplasia (BPD), to add new insights into a better understanding of the pathogenesis of this disease.

Methods

Cord and peripheral blood of neonates (≤ 30 weeks gestational age) was drawn at birth and at the 36th postmenstrual week (36 PMA), respectively. Blood samples were retrospectively subdivided into BPD(+) and BPD(−) groups, according to the development of BPD.

Results

Children with BPD were characterized by decreased afamin, gelsolin and carboxypeptidase N subunit 2 levels in cord blood, and decreased galectin-3 binding protein and hemoglobin subunit gamma-1 levels, as well as an increased serotransferrin abundance in plasma at the 36 PMA.

Conclusions

BPD development is associated with the plasma proteome changes in preterm infants, adding further evidence for the possible involvement of disturbances in vitamin E availability and impaired immunological processes in the progression of prematurity pulmonary complications. Moreover, it also points to the differences in proteins related to infection resistance and maintaining an adequate level of hematocrit in infants diagnosed with BPD.

An iTRAQ-Based Quantitative Proteomic Analysis of Plasma Proteins in Preterm Newborns With Retinopathy of Prematurity

Purpose

Retinopathy of prematurity (ROP) is a vision-threatening complication of a premature birth, in which the etiology still remains unclear. Importantly, the molecular processes that govern these effects can be investigated in a perturbed plasma proteome composition. Thus, plasma proteomics may add new insights into a better understanding of the pathogenesis of this disease.

Methods

The cord and peripheral blood of neonates (≤30 weeks gestational age) was drawn at birth and at the 36th postmenstrual week (PMA), respectively. Blood samples were retrospectively subdivided into ROP(+) and ROP(-) groups, according to the development of ROP.

Results

The quantitative analysis of plasma proteome at both time points revealed 30 protein abundance changes between ROP(+) and ROP(-) groups. After standardization to gestational age, children who developed ROP were characterized by an increased C3 complement component and fibrinogen level at both analyzed time points.

Conclusions

Higher levels of the complement C3 component and fibrinogen, present in the cord blood and persistent to 36 PMA, may indicate a chronic low-grade systemic inflammation and hypercoagulable state that may play a role in the development of ROP.

Development and maturation of the immune system in preterm neonates: results from a whole genome expression study

To expand the knowledge about the consecutive expression of genes involved in the immune system development in preterm neonates and to verify if the environment changes the gene expression after birth we conducted a prospective study that included three cohorts: (A) extremely (gestational age (GA): 23-26 weeks; n = 41), (B) very (GA: 27-29 weeks; n = 39), and (C) moderately preterm infants (GA: 30-32 weeks; n = 33). Blood samples were drawn from the study participants on the 5th and 28th day of life (DOL). The mRNA samples were evaluated for gene expression with the use of GeneChip Human Gene 1.0ST microarrays. Differential expression analysis revealed small subsets of genes that presented positive or negative monotone trends in both the 5th (138 genes) and 28th DOL (308 genes) in the three subgroups of patients. Based on pathway enrichment analysis, we found that most of the pathways that revealed a positive monotone trend were involved in host immunity. The most significantly GA dependent pathways were T-cell receptor signaling pathway and intestinal immune network for IgA production. Overall 4431 genes were differentially expressed between the 5th and 28th DOL. Despite differences in gestational age, patients with the same postconceptional age have a very similar expression of genes.

Impact of antenatal glucocorticosteroids on whole-genome expression in preterm babies

AIM

To study the impact that using antenatal steroid to treat threatened preterm delivery has on whole-genome expression.

METHODS

A prospective whole-genome expression study was carried out on 50 newborn infants, delivered before 32 weeks gestation, who had been exposed to antenatal steroids, including 40 who had received a full antenatal steroid course. Seventy infants not exposed to antenatal steroids formed the control group. Microarray analyses were performed five and 28 days after delivery, and the results were validated by real-time PCR. The study was conducted between September 2008 and November 2010.

RESULTS

Twenty thousand six hundred and ninety-three genes were studied in the infants' leucocytes. Thirteen were differentially expressed 5 days after delivery, but there were no differences at day 28. Four genes related to cancer or inflammation were up-regulated. Nine genes were down-regulated: six were Y-linked and associated with malignancies, graft-versus-host disease, male infertility and cell differentiation and three were associated with pre-eclampsia, oxidative stress and chloride/bicarbonate exchange. Seven gene pathways were up-regulated at day five and only one at day 28. These were associated with cell growth, cell cycle regulation, metabolism and apoptosis.

CONCLUSION

Antenatal steroid therapy affects a limited number of genes and gene pathways in leucocytes in preterm babies at day five of life. The effect is short-lived, but long-term effects cannot be ruled out.

[Intellectual and motor development of extremely low birth weight (≤1000 g) children in the 7th year of life; a multicenter, cross-sectional study of children born in the Malopolska voivodship between 2002 and 2004]

INTRODUCTION

A better understanding of the developmental problems in extremely low birth weight (ELBW) preterm infants may enhance their chances of proper adaptation to their environment and make it possible to retrospectively assess perinatal and neonatal methods of treatment. The aim of the study was to evaluate the cognitive and motor development of ELBW children born from 2002 to 2004 in the 7th year of life. Based on these results and perinatal mortality data, it was established what chance the children have to live free of severe complications.

MATERIAL AND METHODS

Two hundred and four alive newborns with birth weight .1000 g were born in the Malopolska voivodship between 1.09.2002 and 31.08.2004. One hundred and fifteen children (56%) died in early infancy. The study included 81 (91%) children out of the 89 surviving ones. Their mean gestational age at birth was 27.3 weeks. (SD: 2.1 weeks) and their mean birth weight was 840g (SD: 130g). Neurosensory disturbances were assessed in all the children and their cognitive development was evaluated with the use of the WISC-R (Wechsler Intelligence Scale for Children . Revised) scale. The children were divided into 3 groups: group I . normal development (full motor capacity and IQ >84 points and no vision or hearing impairment), group II . mild or moderate impairment (cerebral palsy level I, II or III according to the Gross Motor Function Classification System [GMCS], or IQ 40-84 points, or abnormal vision or hearing, or signs of the hyperactivity syndrome), group III . severe impairment (cerebral palsy level IV, and/or IQ <40 points, or deafness/blindness).

RESULTS

Forty-five (56%) children were included in group I, 25 (30%) in group II and 11 (14%) in group III. Moreover, other neurologic abnormalities, such as uneven development, problems with concentration, or abnormal grapho-motor ability were highly prevalent in the group of ELBW children. The incidence of cerebral palsy in the population studied was 16%, the incidence of deafness and severe hearing impairment was 11%, and blindness and severe vision impairment . 12%. In general, the chance of survival free of severe complications was merely 15% in children with birthweight .700 g, 28% in children with birth weight 701- 800 g, 45% in children with birth weight 801-900 g, and 62% in children with birth weight 901-1000 g.

CONCLUSIONS

1. The data gathered in a regional study may yield valuable information useful in assessing the prognosis of the general health status of ELBW newborns. 2. Most of the children present uneven development, problems with concentration, or abnormal grapho-motor ability, which may be a cause of learning problems and abnormal relationships with peers. 3. A follow-up study up to adulthood is required for this group of ELBW newborns.

[Assessment of somatic development and body composition in the 7th year of life in children born as extremely low birth weight infants (≤1000g); a multi-centre cross-sectional study of a cohort born between 2002 and 2004 in the Malopolska voivodship]

Children born with extremely low birth weight often present delayed growth in the first years of their lives: they remain shorter and weigh less than their peers. Current reports published worldwide state that later in life these children are at an increased risk of cardiac and vascular diseases, diabetes and obesity. Abnormal distribution and the excess of fat tissue predispose them to develop the metabolic syndrome. THE AIM of the study was to evaluate the somatic development of seven-year-old children born with birth-weight ≤1000 g (ELBW) in the Malopolska voivodship and to estimate the content and distribution of fat tissue. Moreover, the risk factors of disturbed somatic development were evaluated.

MATERIALS AND METHODS

Two hundred and four live newborns with birth weight ≤1000 g were born in the Malopolska voivodship between 1.09.2002 and 31.08.2004. One hundred and fifteen of these children (56%) died in early infancy. The study included 81 children in the 7th year of life out of the 89 surviving ones. Their mean gestational age at birth was 27.3 weeks. (SD: 2.1 weeks) and their mean birth-weight was 840 g (SD: 130 g). All the children underwent anthropometric measurements and the thickness of the skin fold over the triceps was measured. Body mass index (BMI) was calculated and the body composition was assessed by multifrequency bioimpedance. The control group consisted of 39 children born at term chosen randomly from the general population and matched with regard to age and sex.

RESULTS

The ELBW children in the 7th year of life were shorter (z-score: -1.06±1.4 p<0.001), had lower body mass (z-score: -0.57±0.9; p=0.01), smaller head circumference (z-score: -1.2±1.3; p<0.001), lower BMI (z-score: -0.99±1.6; p<0.001) as compared to their peers. Fat tissue mass was lower in the ELBW group than in the control group (11% vs 16%; p<0.01). The most retarded somatic development was observed in the group of children suffering from cerebral palsy.

CONCLUSIONS

1. Children born with ELBW, at 7 years of life, present significantly retarded somatic development as compared with their full-term peers. 2. The most important risk factor of somatic development disturbances is cerebral palsy. 3. Children born with low birth weight and ELBW, need long term follow up.

Preterm birth and respiratory disease in later life

Chronic respiratory diseases are a common complication of preterm birth, particularly among very immature infants or those suffering from bronchopulmonary dysplasia. Major progress in the treatment of preterm newborns has changed the pattern of late respiratory complications. The major respiratory problem in infancy and early childhood is respiratory exacerbations caused by infections (particularly viral ones), which need hospitalization. The symptoms become mild in school-age children; however, a group of children still present with chronic airway obstruction defined by recurrent episodes of wheezing and decreased lung function tests (decreased forced expiratory volume). For some preterm infants, particularly those with bronchopulmonary dysplasia, obstructive lung disease persists into adulthood. They are very likely to develop chronic obstructive pulmonary disease or similar disease later in life. In these patients, a program of lung function monitoring and pulmonary prophylaxis by means of elimination of specific risk factors in adulthood is advisable.

Serum tryptase level is a better predictor of systemic side effects than prostaglandin D2 metabolites during venom immunotherapy in children

OBJECTIVES

We performed a prospective study to analyze mast cell mediators as predictors of systemic adverse reactions during rush venom-specific immunotherapy (VIT) in children.

PATIENTS AND METHODS

Nineteen children aged 5-17 years received VIT with Venomenhal (HALAllergy). We analyzed serum tryptase (CAP, Phadia), plasma prostaglandin (PG) D2 metabolites (9alpha, 11beta-PGF2), and urine PGD2 metabolites (9alpha, 11beta-PGF2, tetranor-PGD-M) using gas chromatography mass spectrometry before and after the rush protocol.

RESULTS

Three boys with high baseline serum tryptase values (>7.76 g/L) (P < .001) and low 9alpha, 11beta-PGF2 concentrations developed grade III systemic adverse reactions during VIT. Baseline serum tryptase was lowest in children who had a Mueller grade II reaction (1.93 [0.36]) before VIT and highest in children with a Mueller grade III reaction (6.31 [4.80]) (P = .029). Repeated measures analysis of variance confirmed that, in children who developed systemic adverse reactions during VIT, serum tryptase was higher both before and after desensitization and increased significantly following the procedure. Analysis of PGD2 metabolites in the prediction of systemic adverse reactions during VIT was inadequate (sensitivity 67% and specificity 0.53%), whilst prediction based on serum tryptase was accurate.

CONCLUSIONS

In children with severe systemic adverse reactions to Hymenoptera sting, the evaluation of baseline tryptase levels should be a standard procedure. Children with Apis mellifera venom allergy and baseline tryptase levels higher than 7.75 g/L are at risk of anaphylaxis during buildup. Lower baseline values of plasma and urinary PGD2 metabolite concentration in patients with systemic adverse reaction during VIT suggest that prostaglandin catabolism is altered.

Insulin-like growth factor-1 (IGF-1) serum concentration among 7-year-old extremely low birth weight children--an indicator of growth problems

BACKGROUND

The study aim was to compare somatic development, body composition, insulin growth factor-1 (IGF-1) serum concentration and serum lipid profile between small-for-gestational-age (SGA) and appropriate-for-gestational-age (AGA) 7-year-old extremely low birth weight (ELBW) children and full-term (FT) controls.

MATERIALS AND METHODS

Fifty-seven AGA ELBW children [mean birth weight (BW) 850 g and mean gestational age (GA) 26.4 weeks] and 24 SGA ELBW children (mean BW 833 g, mean GA 29.5 weeks) were evaluated. The control group included 37 age- and sex-matched FT children from one outpatient center.

RESULTS

Nine AGA and four SGA were found to have short stature defined as height < 3rd percentile for chronological age (p = 0.9). In the AGA cohort, the results of weight, head circumference, triceps skin fold and body mass index (BMI) measurements were significantly reduced in the short-stature subgroup. IGF-1 serum concentrations differed significantly between short-stature and normal-stature subgroups (121 vs. 193 ng/mL; p = 0.02). In the SGA cohort, weight and serum concentrations of total cholesterol (5.03 vs. 4.26 mmol/L; p = 0.04), LDL cholesterol (3.24 vs. 2.38 mmol/L; p = 0.01) and IGF-1 (113 vs. 211 ng/mL; p = 0.01) differed significantly between the short-stature and normal-stature subgroups.

CONCLUSIONS

Short stature at the age of 7 years was diagnosed in a similar percentage of AGA and SGA former ELBW infants. In both cohorts short-stature children have significantly lower weight and serum IGF-1 levels. IGF-1 seems to be involved in prolonged growth restriction among ELBW infants, regardless of whether they were AGA or SGA.

[Diagnosis and venom specific immunotherapy (VIT) in allergic children in Poland--how much the current practice follows the international guidelines?]

INTRODUCTION

Insect venom allergy requires a high level approach adequate to allergy intensity. In case of severe IgE-mediated sting reactions, in children older than five years, venom immunotherapy is a treatment of choice.

AIM

Identification of current practices applied to venom allergic children in Poland and their adherence to the international guidelines.

METHOD

Questionnaire survey concerning diagnostic and treatment rules was carried out in 8 centres of pediatric allergology, based on a similar audit conducted in the United Kingdom [Diwakar L. et al. Clin Exp Allergy 2008, 38: 1651].

RESULTS

In 5 centres both RAST and SPT tests were used as the first line of investigation. Subsequently 6 centres performed IDT. In three centres baseline serum tryptase levels were estimated. In case of sensitization to both bee and wasp venom in a child with the history of severe systemic reaction, but uncertain culprit insect, specific venom immunotherapy with both venoms was practised by 2 centres. In systemic reaction and not-detectable IgE in 6 centres child was followed-up in 6-12 months. Antihistamine premedication concerned all children in 7 centres. Six-week interval between booster doses was applied in half of centres. A target dose equal 100 mcg was used in 7 centres. Similarly all centres practiced 3-5 five year period of VIT.

CONCLUSIONS

In Poland current practice with venom allergic children was conducted in congruence with most of the recommendations.

[Adaptation of Vespide Allergy Quality of Life Questionnaire for Polish children with venom allergy and for their parents]

Aim of the study was to assess validity and reliability of adaptations of VQLQ for Polish children with Hymenoptera venom allergy and their parents. Sample under study consisted of 73 children aged up to 14 years, who were treated with specific venom immunotherapy (VIT) in 2008 in centres conducting this procedure in Poland, and their parents. Theoretical validity of the scales was assessed with exploratory factor analysis using principal component analysis method. Reliability of the scales was assessed in terms of internal consistency with Cronbach alpha coefficient. Results of analysis showed that both scales measure 4 dimension of quality of life and reliability of scales measuring particular dimensions is at least acceptable in case of scale for children, and high in case of scale for parents. Both adapted scales are valid and reliable tools measuring quality of life in children with Hymenoptera venom allergy and their parents' quality of life in the face of child's allergy.

[Difficulties in diagnosing febrile states in 3-month-old infant]

Wide spectrum of infectious causes should be considered while diagnosing febrile states in infants.The aim of study is to present the case of 3-month-old infant with febrile states. Boy was admitted to Department of Pediatrics to Infant Unit because of the febrile states lasting for 4 weeks. Perinatal history: first pregnancy, cesarean section in 39 weeks of gestation due to mother's pointed condyloma, birth weight 3140 g, Apgar score 10 in first minute. There was no information about the course of pregnancy, mother's diseases, father was unknown. The child was ambulatory cured with several antibiotics because of the respiratory tract infections. On admission to hospital the general status of the infant was quite good, there was respiratory tract infection, hepatomegaly, and aphthae found in physical examination. Increased levels of inflammation markers and elevated activity of liver enzymes were observed in laboratory tests. Perihilar inflammatory density was found in chest radiogram. After finishing pharmacological treatment there were no pathological changes on auscultation of the lungs. The hospital course was complicated with Rotaviral infection. As the febrile states and hyperactivity of liver enzymes persisted, the diagnostics was extended. There was sepsis, neuroinfection, number of bacterial and viral infections excluded. There was also urine collected for the levels of catecholamines, the result was normal. Due to reverse proportion of the CD4 and CD8 lymphocytes, persistent active CMV infection and clinical status of the child, HIV test was performed. There was confirmed presence of p24 antigen of HIV in immunological test. The child was transfered to Child's Infectious Diseases Unit of Stefan Zeromski Hospital in Cracow to verify the result of laboratory test and start therapy.

[Cytomegalovirus infection--diagnostic and therapeutic difficulties in neonatal intensive care unit]

BACKGROUND AND AIM

Lack of routine diagnostic test in most of pregnancies, not prominent symptoms in newborn, not satisfactory diagnostic test, no screening and lack of therapeutic consensus create difficulties in CMV treatment in neonatal period.

AIM

Evaluation of frequency of CMV infection, way of making diagnose and treatment in NICU.

MATERIAL AND METHODS

This is retrospective cross-sectional study included 1491 newborns in period from 1.05.2003 till 8.11.2009 treated in NICU. In case suggested CMV infection diagnostic tests were performed: viral detection in urine, specific IgG and IgM level, and in few cases viral detection by PCR in blood or cerebrospinal fluid. According to the positive results above tests, the treatment with Gancyclovir or Foscavir was introduced.

RESULTS

27/1491 patients had CMV infection. 16/27 presented symptoms for 3rd week of life (59%). 10/27 died, 2 because of generalized CMV infection. 13/27 were treated (11 with Gancyclovir, 2--Foscavir). For first 3 weeks of life 139/1491 had diagnostic tests, 86 later (Me: 13 day, 25%-75%: 5-32 day). The viral test in urine specimen was performed in 166/1491 (all with CMV infection). First test was positive in 19/27 cases of CMV infection, 2/27 cases had test not for interpretation and 6/27 had negative. The sensitivity of this test was 76%, specificity 100%. Serologic tests were performed in 68/1491 before 3rd week of life, 18/1491 later (Me: 7 day, 25%75%: 3-16 day). The sensitivity of IgM test was 15.4%, specificity 100%, IgG sensitivity 93.3%, but specificity 28%. High IgG level > 100 AU/ml had sensitivity 75%, specificity 58,8%. 16/1491 neonates had viral test with PCR (9/27 with CMV infection), sensitivity was 66.6%, specificity 100%.

CONCLUSION

Quite often lack of early symptoms, not satisfying sensitivity of urine viral test and IgM, low specificity of IgG make problematic diagnosing of CMV infection. 2 cases of death because this infection should be taken under discussion on indications for treatment.

Correlation between early neonatal diet and atopic symptoms up to 5-7 years of age in very low birth weight infants: follow-up of randomized, double-blind study

The influence of early feeding on the risk of atopic diseases has been studied in full-term newborns, not in very low birth weight infants (VLBW). The study evaluated effect of early feeding of VLBW infants with either cow's milk-based formula (CMF) or extensively hydrolyzed milk formula (HF) on incidence of atopic diseases and markers of atopy at 5-7 years of age. This was a follow-up of the randomized, double-blind study evaluating the influence of different enteral feeding protocols on the early morbidity of VLBW infants. In the original study 80 children were randomly allocated into 2 groups receiving during first month of life HF (experimental group) or CMF (control group). At the age of 5-7 years, 62 children among 74 available (84%) with mean birthweight 1124g were evaluated according to standardized ISAAC (International Study of Asthma and Allergies in Childhood) protocol. Total IgE level, specific IgE, lymphocyte CD4+CCR4+/CD4+CXCR3+ ratio and skin prick tests (SPT) were done. Prevalence of obvious allergic diseases was not significantly different between the studied groups (HF: 12/33; CMF: 6/29; RR [relative risk] HF vs CMF: 1.76; 95%CI [confidence interval]: 0.76-4.09). Comparison of atopic status across groups revealed similar rate of positive markers of atopy: IgE (RR: 2.57 95%CI: 0.91-8,08), SPT (RR: 5.13; 95%CI: 0.93-31.6), lymphocyte CD4+CCR4+/CD4+CXCR3+ ratio (OR: 2.32; 95%CI: 0.78-7.53) in the both studied groups. Based on the carried out follow-up study we were unable to confirm the usefulness of hydrolyzed formula in prevention of allergy in an unselected cohort of very low birth weight infants.

Can early echocardiographic findings predict patent ductus arteriosus?

BACKGROUND

Prophylactic treatment with prostaglandin synthetase inhibitors (PSI) is potentially harmful. Moreover, long-term benefits of prophylactic use of indomethacin or ibuprofen are not proven. Early treatment of a high-risk population is alternative to the routine prophylactic use of PSI, but it remains unclear which newborn is at greatest risk for patent ductus arteriosus (PDA).

OBJECTIVE

Evaluation of the prognostic value of early echocardiographic studies with respect to PDA in later life.

METHODS

Sixty preterm infants with a mean birth weight of 1,087 g and mean gestational age of 28.5 weeks were included in a prospective study. Cardiac scans were performed in all newborns on entry into the study (within 12-48 h after birth) and further in case of clinical suspicion of PDA or obligatorily on the 7th and 28th days of life. There was no prophylactic or treatment use of any PSI during the study period. Newborns were divided into 2 cohorts: with significant left to right shunt requiring surgical ligation of PDA (n = 16) or without significant PDA during follow-up (control group, n = 44).

RESULTS

On entry, the mean internal diameter of the ductus arteriosus (2.6 vs. 0.91 mm/kg; p < 0.01), mean cardiac index across aortic valve (2.96 vs. 2.37 l/min/m(2); p < 0.01) and early filling peak velocity (43.1 vs. 33.7; p = 0.01) were significantly higher in babies who later needed surgical ligation of PDA. There was no difference in the mean values of the other echocardiographic parameters studied. An early ductal diameter of >1.5 mm/kg predicted symptomatic PDA with a sensitivity of 94% and a specificity of 73%, and its positive predictive value equaled 57% and negative predictive value amounted to 97%.

CONCLUSIONS

Early echocardiographic studies possess negative predictive value and may decrease unnecessary surgical ligation of PDA in very low birth weight infants.

Genetic risk factors of bronchopulmonary dysplasia

The aim of the study was to assess the association between bronchopulmonary dysplasia (BPD) and polymorphisms of genes coding for vascular endothelial growth factor (VEGF), transforming growth factor (TGF-[beta]1), insulin-like growth factor (IGF-1), and 5,10-methylenetetrahydrofolate reductase (MTHFR). A sample of 181 newborns with mean gestational age of 28 wk was prospectively evaluated. Molecular analysis of TGF-[beta]1 -800G>A, -509C>T, 10T>C, 25G>C, VEGF -460T>C and 405G>C and MTHFR 677C>T polymorphisms were performed and the number of CA repeats in the promoter region of IGF-1 gene was assessed. The frequency of all TGF-[beta]1, IGF-1, and MTHFR polymorphisms, as well as the frequency of VEGF 405G>C polymorphism was similar in all groups. The newborns with -460TT and -460CT genotypes were significantly overrepresented in the BPD groups compared with the no BPD group. Multivariate analysis revealed that carrying T allele increased the risk of BPD by 9% (95%CI: 2-14%) above the baseline risk established for given gestational age, length of oxygen therapy, and sex. Based on our data from a single center, we propose that VEGF -460T>C polymorphism may influence the risk of BPD.

Comparative analysis of zinc status, food products' frequency intake and food habits of 11-year-old healthy children

Children are particularly vulnerable to zinc (Zn) deficiency during periods of rapid growth and development such as infancy and adolescence. The aim was to find the relationship between food frequency, intake, food habits and zinc status in 11-year-old healthy children from southern Poland. The study group comprised children (n = 157) in the age range 11.0 +/- 0.4 years. The level of Zn in serum, erythrocytes and hair samples was measured using atomic absorption spectrophotometry. The parents of children examined completed a special food frequency questionnaire. The Zn concentration in hair (boys 182.98 +/- 65.63 microg x g(-1), n = 78; girls 203.82 +/- 39.80 microg x g(-1), n = 79; p = 0.0171), erythrocytes (8.60 +/- 2.76 mg x l(-1), n = 50) and blood serum (0.79 +/- 0.15 mg x l(-1)) correlated significantly (p < 0.05) with frequency intake of different products (hair: meat, rolls, fruit juices without additives, brawn, pate, barley, black pudding, fish canned, chips, margarine used for cooking, bacon; erythrocytes: fruits, matured cheese, dishes of meal, white cottage cheese, fruit juices without additives, cakes and cakes with cream, margarine used for bread spread; blood serum: bread, fruits, milk, kefir, yoghurt). The relationship of the Zn amount in food products, food frequency intake and the concentration in different healthy children tissues is influenced by many internal and external factors.

[Molecular studies in a population of children with bronchial asthma. I. Polymorphism in the promotor region of gene CD14]

Allergic asthma is associated with the recruitment of the inflammatory cells into the bronchial mucosa. Surface expression of CD14, a marker of activation and differentiation of macrophages/monocytes, was suggested to protect against Th-2 response.

OBJECTIVE

To investigate clinical effects of genetic polymorphism of CD14 promoter in asthmatic children.

METHODS

In ISAAC survey, 50 children with asthma were identified (wheezing in the last year, serum IgE level > 150 kIU/l, positive bronchial challenge test with aerolized hypertonic saline) and 73 children without the above signs. Age range of surveyed children was 13-14 years. Genotypic pattern of CD14 promoter -159 C to T transition was assessed by RFLP method.

RESULTS

There was no difference in the allelic (0.36 vs. 0.38 for -159T) or genotype frequencies (0.12 vs. 0.15 for -159TT) of CD14 polymorphism between allergic asthmatics and controls. Moreover, there was no relationship between CD14 genotype and serum IgE level or bronchial hyper-responsiveness.

CONCLUSION

Our results do not confirm the association of CD14 polymorphism (promoter -159 C to T transition) with asthma in Polish children.

The influence of lead and cadmium environmental pollution on anthropometric health factors in children

THE AIM

The aim of the study was to examine the relationship between environment pollution (lead and cadmium) and selected anthropological factors.

MATERIAL AND METHODS

The study group comprised 267 children, aged 11 +/- 0.4. Blood sampling and anthropological measurements were carried out in Kraków (polluted area) and in the Krosno region (low polluted area) in 1995. The lead and cadmium concentrations in the whole blood were determined using atomic absorption spectrometry with a graphite furnace and automatic dosage. The anthropometric measurements were made at the same time as the blood collection.

RESULTS

The blood lead content in boys and girls was: 5.89 +/- 2.54, 5.01 +/- 1.62 micrograms/dl respectively, and the cadmium blood content was: 0.65 +/- 0.30, 0.68 +/- 0.47 microgram/l. Body mass and height did not correlate with lead and cadmium concentrations in the children's blood. Smaller head circumferences, independently of gender, were associated with a higher cadmium level. The values of four skin-folds (on the arm: biceps, triceps, under scapular bone and above iliac crest), as well as the percentage of fat content in the organism (PFDWB) calculated by the Slaughter-Lohman equation was higher in girls than in boys.

CONCLUSIONS

1. The relationships between cadmium and lead blood levels in children on the one hand and the degree of environmental pollution with these metals, and the gender of the children on the other were observed. The boys accumulated more lead, whereas the girls absorbed more cadmium. 2. Anthropometric analysis did not show a significant influence exerted by the polluted environment on the basic auxological parameters. In the group of children examined, the only differences observed were related to gender, head circumferences and indicators of obesity.

[Gene therapy--hopes and fears]

Gene therapy assumes the correction of a genetic defect by the delivery of a correct DNA sequence to the target cells. Depending on the target cells two types gene therapy have been defined: somatic and germinal. By July 1998, 351 protocols of somatic therapy were approved by the Recombinant DNA Advisory Committee. The majority of protocols focus on cancer therapy and monogenic diseases. By now, still there is more unfulfilled expectation than clinically sound achievements, since no effective prevention or successful treatment for genetic diseases or cancer have been developed. Germline genetic modification is considered as the treatment of choice for such a diseases like retinoblastoma. Tay-Sachs, Lesch-Nyhan and metachromatic leuko-dystrophy. This approach which is still illegal or prohibited by rules in many European countries, is gathering more and more advocates. Once we learn how to control gene expression the perspectives for clinical application of gene therapy might be enormous. The safety of genetic modification of gametes or embryonal stem cells remains to be properly addressed and successfully solved. The ethical issues of germinal gene therapy are still the subject of controversial opinions among the scientists, lawyers and philosophers.

[Genetic background of retinoblastoma]

Retinoblastoma is a malignant tumour of the eye ball, which develops as a result of the mutation of both alleles of RB-1 gene. Molecular mechanisms and their implications in clinical diagnosis and genetic counselling in retinoblastoma families are discussed.

[Neural tube defects (NTD)--assessment from the perspective of 25 years of studies]

The present paper illustrates the authors 25-year experience in step by step approach to the definition of environmental and genetic background of neural tube defects. Based on the birth defects registry, a complete ascertainment of all deliveries was performed in Southern Poland during two period: 1970-1972, and 1979-1981. The birth prevalence of neural tube defects (NTD), as well as other CNS malformations was determined. The empiric recurrence risk was calculated as 3.2% +/- 1.6. Based on this figure, the relative risk (RR = 37.6 p < 0.001) and heritability (h2 = 74.7 +/- 6.7) were estimated. Our own modification of Morton's complex segregation analysis was applied. Three Mendelian (dominant, additive and recessive) and one multifactorial model were tested. The results did not provide a clear cut discrimination between different models; however the lowest 2 value was obtained for additive inheritance with 61% of penetrance and the frequency of sporadic cases equaled 55%. A search for genetic markers did not support the hypothesis that HLA-A,B,C loci are equivalents of T/t like locus in mice. The results of the study on transcobalamine levels in amniotic fluid may suggests that different transcobalamine metabolism reflects phenotypic expression of genetic susceptibility to NTD development. Current research and future perspectives on genetic and environmental background of NTD are also presented.

Response-dose ratio as an index of bronchial responsiveness to hypertonic saline challenge in an epidemiological survey of asthma in Polish children

This epidemiological survey was done to evaluate the bronchial responsiveness (BHR) to a 4.5% hypertonic saline (HS) challenge in 13-14 year-old schoolchildren. BHR was measured by the response-dose ratio in which the response was estimated by the decline of FEV1 index of BHR (IxFEV1). Validity of the HS challenge test as a screening test for confirmation of reported asthma symptoms and the diagnosis of asthma was assessed. With a cutoff of 90th percentile of IxFEV1 in controls, the test sensitivity and specificity for asthma symptoms in the last 12 months was 44% and 90%, respectively. For the diagnosis of asthma the test sensitivity was 67% and specificity 90%. The mean log transform of IxFEV1 was significantly higher in children with more than three episodes of wheezing in the last 12 months and a diagnosis of asthma than in controls. Moreover, in the group with more than three episodes of asthma in the last 12 months the mean IxFEV1 was higher in girls than in boys. There was no gender difference in other groups of asthmatic children and controls. In Polish schoolchildren the prevalence of BHR to HS was 12.5% when adjusted to the prevalence of wheezing in the last 12 months. By multiple linear regression analysis, factors associated with BHR were serum levels of total IgE in children and of maternal IgE, as well as children's peripheral blood eosinophil counts. Also, the size of skin reaction to mite and dog allergens correlated with BHR.

[Diagnostic value of selected eosinophil activity parameters in children with hay fever]

Seventy three children aged 5-15 years were involved in the survey. Thirteen children suffered from seasonal allergic rhinitis (SAR), fourty four children suffered from seasonal allergic rhinitis and bronchial asthma (SAR-A), sixteen patients with no allergic symptoms were treated as a control group (CG). All the patients were examined twice: in July--during the highest pollen season and in December--period free of pollen. During each examination samples were collected to measure the following parameters: blood eosinophilia, serum eosinophil cationic protein (ECP) and eosinophil percentage in the nasal mucosal smears (nasal eosinophilia). In statistical analysis values of all parameters in pollen and free of pollen seasons were compared the groups of patients as well as within the groups. In winter values of: blood eosinophilia, ECP and nasal eosinophilia were statistically higher in SAR-A group in comparison to SAR group and CG, simultaneously there was no statistical difference in blood eosinophilia and ECP between SAR group and CG. In the pollen season the highest values of all parameters were observed in SAR-A group. SAR group values were higher in comparison to control group. The difference between groups was significant. Both groups of allergic patients (SAR, SAR-A) revealed statistically higher values of all measured parameters in pollen season in comparison to winter. In CG only level of ECP was significantly higher in July than in December.

[Pollen allergy. II. Diagnosis and treatment]

Pollen allergy--one of the most frequent allergies in people is diagnosed by combined data, derived from patient's history together with in vitro and in vivo examinations. Basic in vivo examinations consist of skin prick tests with chosen allergens, functional tests of upper and lower respiratory tract, specific as well as non-specific nasal and bronchial challenge tests. The major role among in vitro examinations is played by those tests, which confirm atopic background of the disease (total and specific IgE). Other tests, like those for T-cell function and tests for effector cells activation, have secondary importance. Patients who are asymptomatic but endangered by the possibility of symptoms occurrence, are treated by primary prevention. Complex therapeutical approach consists of causal treatment (identification of allergens, specific immunotherapy), secondary prevention and symptomatic pharmacology.

[Bronchial asthma: do boys or girls have the highest incidence?]

The aim of the study was to assess the gender related prevalence of asthma and asthma symptoms in schoolchildren. The survey was performed using standardized ISAAC questionnaire in two age groups: 6-7 yr. (n = 2281; girls 49.7%) and 13-14 yr. (n = 4849; girls 49.8%). It was revealed that in older group the prevalence of ever diagnosed asthma was lower in girls than in boys (2.0% versus 3.3%; odds ratio [OR] = 0.58; p = 0.004). But the prevalence of symptoms: wheeze ever (OR = 1.16; p = 0.056), current wheeze (last 12 mo) (OR = 1.26; p = 0.029), current exercise wheeze (OR = 1.40; p = 0.0008), current night cough (OR = 1.67; p = 0.0001) were higher in girls than in boys. However, in younger group of schoolchildren the prevalence of ever diagnosed asthma and asthma symptoms were higher in boys (5.1% male versus 3.5% female). The girls in comparison to boys revealed lower risk of ever asthma diagnosis (OR = 0.66; p = 0.056) and symptoms: wheeze ever (OR = 0.63; p = 0.0001), current wheeze (OR = 0.69; p = 0.003), current exercise wheeze (OR = 0.59; p = 0.008) and current night cough (OR = 0.70; p = 0.0003).

[Prevalence of allergic diseases in schoolchildren in Krakow and Poznan (based on a standardized ISAAC questionnaire)]

The study population included children aged 6-7 and 13-14 years from primary schools in Kraków (2302 and 2967 children respectively) and Poznań (3132 and 4069 children respectively). The prevalence was assessed using ISAAC questionnaire. In younger age group the number of children with diagnosed asthma and presenting asthma symptoms was significantly higher in Kraków than in Poznań. In older age group higher percentage was observed in Kraków in relation to wheeze ever and nocturnal cough during last year. Pupils from Kraków had symptoms of allergic rhinitis and were diagnosed as allergic rhinitis more frequently than from Poznań. Symptoms suggestive for skin allergy were more often observed in Kraków, but the differences were significant in relation to symptoms during last year in both age groups and in relation to symptoms ever in older age group. Our study revealed discrepancy between the prevalence of symptoms of asthma and allergic rhinitis and the prevalence of established diagnosis.

[Chromosome aberrations in patients with papillary thyroid cancer and other neoplasms]

Cancer is essentially a genetic disease resulting from congenital or acquired alterations in some cells of the patient. Such changes may occur in particular oncogens and are responsible for the tumour phenotype of the affected population of cells. In contrast, unaltered tumour-suppressor genes are responsible for suppressing the neoplastic phenotype, and their inactivation by deletion or mutation permits cancerous development in the affected cells. The genetic model of carcinogenesis is based on the idea mutations at the DNA level, what creates a functional imbalance between the oncogenes and the tumour-suppressor genes, resulting in uncontrolled clonal proliferation. The ret/PTC oncogene is unique to papillary thyroid cancer. The paper presents a correlation analysis between chromosomal changes in papillary thyroid cancer and abnormalities of chromosomes in patients with breast cancer and chronic lymphocytic leukemia.

Familial four breakpoint complex chromosomal rearrangement as a cause of monosomy 9p22-->pter and trisomy 10p11.2-->pter and 11q21 analysed by dual and triple colour FISH

A familial four breakpoint complex chromosomal rearrangement involving chromosomes 9, 10, and 11 was ascertained through a child with dysmorphic features, hypertrophic cardiomyopathy, and hypotonia. A cryptic insertion, invisible in G banded chromosomes was identified by fluorescence in situ hybridisation (FISH) using chromosome specific libraries. Possible mechanisms of its formation as well as karyotype-phenotype correlation are discussed.

A search for environmental and genetic background for neural tube defects: twenty-five years of experience

The present paper illustrates the author's 25-year experience in a step by step approach to the definition of environmental and genetic background of neural tube defects. Based on the birth defects registry, a complete ascertainment of all deliveries was performed in Southern Poland during two periods: 1970-1972, and 1979-1981. The birth prevalence of neural tube defects (NTD), as well as other CNS malformations was determined. The empiric recurrence risk was calculated as 3.2% +/- 1.6. Based on this figure, the relative risk (RR = 37.6 p < 0.001) and heritability (h2 = 74.7 +/- 6.7) were estimated. Our own modification of Morton's complex segregation analysis was applied. Three Mendelian (dominant, additive and recessive) and one multifactorial model were tested. The results did not provide a clear cut discrimination between different models; however the lowest x2 value was obtained for additive inheritance with 61% of penetrance and the frequency of sporadic cases equaled 55%. A search for genetic markers did not support the hypothesis that HLA-A,B,C loci are equivalents of T/t like locus in mice. The results of the study on transcobalamine levels in amniotic fluid may suggests that different transcobalamine metabolism reflects phenotypic expression of genetic susceptibility to NTD development. Current research status and future perspectives on genetic and environmental background of NTD are also presented.

[Pollen allergy. I. Pathophysiology and clinic]

Pollen allergy constitutes about 1/3 of allergic disorders in people. Clinical manifestation of the disease depends on the natural allergen exposure. Main clinical symptoms are dealing with conjunctivitis, allergic rhinitis, bronchial asthma. Permanent increase in number of pollen sensitive patients observed during last years, depends on atopic genetic background, as well as natural allergen exposure and other environmental factors. Better understanding of pathophysiological mechanisms underlying the disease and opportunity to monitor the degree of allergen exposure seems to play the vital role in current treatment and prophylaxis. The allergic reaction takes place in two phases--the first one--early response (EAR) depends on IgE receptors binding which results in mast cell and basophils activation, in the second one--the late response (LAR), adhesive molecules, eosinophils, lymphocytes and their products, as well as neuropeptides are engaged. Also homeostasis of respiratory tract mucous membrane plays an important role at this stage.

[The effect of air pollution on the prevalence of asthma in schoolchildren from Krakow]

The aim of the study was to assess the relationship between asthma, wheezing prevalence and the rate of air pollution in Kraków. In the survey of 6696 schoolchildren aged 12-14 year, ISAAC questionnaires were performed. According to the distribution of the mean annual concentration of dust particles (PM10) and sulfur dioxide, four classes of these compounds were established. In the similar way, the lead concentration in garden soil and lettuce was categorized into three classes, which were surrogates of the automobile exhaust. Children's passive smoking was established by questionnaire. The study revealed a significant association and a positive correlation between the prevalence of asthma diagnosis and the soil and lettuce lead concentrations. Wheezing history (past and current) was significantly correlated with soil lead classes and the classes of dust particles (PM10). Maternal smoking was significantly associated with the asthma diagnosis and past or current wheezing. A significant relationship was found between paternal smoking and wheezing during and/or post exercise.

[Evaluation of hyperresponsiveness to the exercise challenge test in school children]

Bronchial hyperresponsiveness (BHR) to the exercise challenge test was measured in 161 pupils randomly chosen from the epidemiologic survey of 2967 schoolchildren (13 to 14 yr of age). In the study group there were 73 pupils who were identified as "ever wheezers" by the ISAAC questionnaires, and 88 ones as the control group. BHR was measured as the percentage drops in FEV, FEF50, FEF25-75 from the baseline (% delta FEV1, % delta FEV50%, % delta FEF25-75%). The % delta FEV1 was significantly higher in the "ever wheezers" comparing to the control group, and this parameter was also significantly higher for the "wheezers in the last 12 mo" in comparison to "ever wheezers", who had no symptoms in the last year. The "ever wheezers" group had higher % delta FEF50%, % delta FEF25-75% but the value was not significant when compared to the control group. In the epidemiologic survey, the sensitivity and specificity for the exercise challenge test as a screening test (level %FEV1 > 11%) to identify "wheezers in the last 12mo" were 39% and 81%, respectively, and to identify the "diagnosed asthma" group were 40% and 76%. The BHR was modified by atopy (measured with the allergic skin tests) and the diagnosis of asthma.

[Genetic background of atopy]

The paper presents contemporary views on atopic inheritance patterns. Results of molecular studies are presented which map genes linked with disturbances in IgE to chromosomes 5 and 11. The role of HLA antigens in atopic reaction mechanisms is also discussed.

[The influence of lead on fetal development]

The paper determines the mechanism of a noxious effect of lead upon the organism of a child. The authors identify the environmental sources of lead and discuss its metabolism in human body. They also determine the mechanism of toxic lead effect with a special emphasis placed on its transport through the placenta and the resulting detrimental effects for the fetus. The paper also discusses the results of prospective studies indicating a correlation between the exposure of a pregnant woman to lead and the future mental development of her child.

[Linkage analysis between HLA and GLOI with congenital adrenal hyperplasia due to 21-hydroxylase deficiency]

A linkage analysis was performed between congenital adrenal hyperplasia and HLA-ABC and GLOI loci. On the basis of studies carried out in 23 (HLA) and 20 (GLOI) informative families, linkage between adrenal hyperplasia and locus B of HLA was confirmed, whereas that with GLOI was ruled out.

[HLA haplotypes in families of children with congenital adrenal hyperplasia]

The haplotypes of class I HLA system were determined in a group of 32 children with congenital adrenal hyperplasia and classic form of 21-hydroxylase deficiency. The haplotype frequencies were analyzed and compared to those of the control population. Haplotypes containing the HLA-B-47 antigen were significantly more frequent among the families of patients than among the control population. Among the patients, haplotypes HLA A3-B47-Cw6 and HLA A3-B47-Cwx constituted 50% of all the observed haplotypes with the HLA-B47 antigen. It is stressed that the frequency of homozygotic systems for antigens determined by locus HLA-A (33.34%) and for antigens with locus HLA-B (22.23) were much higher in the affected children.

[Class I HLA antigens in children from families with congenital adrenal hyperplasia]

Congenital adrenal hyperplasia (CAH) is a syndrome of adrenal steroid metabolism errors with an autosomal inheritance model. The most common metabolic defect is 21-hydroxylase deficiency. It has been demonstrated that 21-hydroxylase genes are in close association with HLA antigens. I HLA antigens were typed in a group of 32 families of children with CAH-type 21-hydroxylase deficiency with salt loss. The antigen frequencies were determined and compared to those of the control population. The studies revealed that two HLA antigens determined by the B Locus, i.e. HLA-B47 and HLA-B61, showed a highly significant frequency (chi 2 corresponding to 404,5259 and 23,7808, respectively). The calculated relative risk and etiologic fraction values were extremely high, distinguishing the population of patients and their parents. The RR value among patients was 427.1 for HLA-B47 and 7.8 for HLA-B61 antigen. Studies on the correlation between HLA and CAH indicate an association with HLA-B47 and HLA-B61 antigens.

Molecular analysis of alleles segregation at RFLPs within RB-1 gene in four families with hereditary retinoblastoma

Four families with suspected hereditary retinoblastoma in proband and one other family member were examined by genetic segregation analysis of the RB-1 gene loci with specific RFLPs of chromosome 13. Two families, TA-6 and partially CK-46, were informative using this method. In TA-6 family healthy sister (TA-6/10) of the proband was shown not to be a carrier of the mutant RB-1 gene. These results show that the segregation analysis of RB-1 gene loci with specific RFLPs, used as the DNA markers, could be helpful in the genetic diagnosis and counselling in families with hereditary retinoblastoma.

Phenylketonuria in Poland: 66% of PKU alleles are caused by three mutations

In order to investigate the molecular basis of phenylketonuria (PKU) in the Polish population, we screened 44 mutant chromosomes from PKU probands for six known mutations, frequently occurring in western European countries, by polymerase chain reaction amplification of their genomic DNA and hybridization with allele-specific oligonucleotides. Our results show that the majority (66%) of all PKU alleles are characterized by three different mutations: in codon 408 (56.8%), codon 158 (6.8%) and codon 261 (2.27%). Of the mutant haplotype 2 alleles, 96% were linked to the mutation in codon 408. Out of five mutant haplotype 4 alleles, three showed the codon 158 mutation, and out of four mutant haplotype 1 alleles, one had the codon 261 mutation. In two families, MspI digests revealed an additional 13.5-kb band similar in length to that previously reported. However, analysis of exon 9 excluded the presence of the T to C transition originally described, indicating a new MspI variant in the Polish population.

Molecular analysis of PKU haplotypes in the population of southern Poland

Out of a population of 138,598 infants born in southern Poland between 1987 and 1989, and screened for phenylketonuria (PKU), 28 cases were ascertained probands and their parents were isolated and eight polymorphic restriction sites were analyzed within the phenylalanine hydroxylase gene region. Twenty-one different haplotypes (HT) were revealed, five of them representing new categories. The most common haplotypes among those carrying normal alleles were: HT1 (27.3%) and HT4 (11.4%). Within the group of haplotypes with mutant alleles the most frequent was HT2 (56.8%), whereas the frequency of this haplotype in other European populations, such as French, Danish and German, ranged from 12% to 24%. HT3, being the most common in Danish (38%), and relatively frequent in the other western European (13-14%) populations, appeared to be very rare in our sample (2.3%). The mutation of codon 408 (exon 12, C----T, Arg----Trp), which has been described to be tightly linked to HT2, was tested on amplified DNA by dot-blot hybridization. This mutation was found in 25 out of 44 proband chromosomes. In one case it was linked to HT5, in the remaining 24 to HT2. Our results confirm molecular heterogeneity of PKU haplotypes, as well as their significant interpopulation variation.

Two siblings with phenotypes mimicking peroxisomal disorders but with discordant biochemical findings

The authors present a report on two sibling with a nearly identical phenotype mimicking peroxisomal disorder but with totally discordant biochemical findings. In an attempt to confirm the diagnosis of a peroxisomal disorder, plasma levels of very long chain fatty acids (VLCFA) and phytanic acid were determined. In addition, fibroblasts profile of VLCFA and plasmalogen levels were evaluated for Case 2. Pathomorphological examinations represented by lymph node and kidney biopsies as well as postmortem examinations of liver, adrenals and brain were performed in Case 1. The phenotypes of both siblings showed marked resemblance to those observed in children with Zellweger syndrome. The results of biochemical tests performed in Case 1, together with abundant peroxisomes in the liver and the wide spectrum of clinical abnormalities suggest pseudo-Zellweger or Zellweger-like syndromes, but no conclusive data have been found. The plasmalogen level in fibroblasts as well as the fibroblasts profile of VLCFA noted in Case 2 were within the normal range, thus excluding the possibility of a peroxisomal disorder. The striking phenotype resemblance of the siblings mimicking Zellweger, together with discordant biochemical findings, are difficult to explain on the basis of currently available tests.

Juvenile rheumatoid arthritis. Monocyte dysfunction in selected patients

The in vitro parameters of cell-mediated immunity were studied in 20 children with an established diagnosis of Juvenile rheumatoid arthritis (JRA) (age range 4-15 years) and 23 age- and sex-matched healthy children. (No attempt was made to correlate the observed changes with clinical course or treatment). We are not certain, at this time, of clinical relevancy or the generalizability of the findings. The normal level of T-lymphocytes (CD3+) and normal proportions of CD4+ and CD8+ lymphocytes were seen in children with JRA. The in vitro response of lymphocytes to T-cell mitogen phytohemagglutinin (PHA) also was normal. The suppressor activity of JRA monocytes was essentially the same as controls. In contrast, monocytes from patients with JRA showed the following: decreased expression of receptors for Fc part of IgG immunoglobulin (FcR), diminished nitro blue tetrazolium (NBT) reduction activity, and depressed expression of Ia.7 major histocompatibility complex (MHC) class II determinants. This indicates that certain monocyte functions in selected patients with a variety of manifestations of JRA are depressed.