Suboptimal push-out bond strengths of calcium silicate-based sealers.

AIM: To evaluate and compare the push-out bond strength of MTA Fillapex (Angelus, Londrina, Brazil) and iRoot SP (Innovative BioCeramix Inc., Vancouver, Canada) to the dentine walls of root canals. AH Plus (Dentsply DeTrey, Konstaz, Germany) and MTA (Angelus, Londrina, Brazil) were used as reference materials. METHODOLOGY: Sixty extracted human single-rooted teeth were selected. After standardized canal preparation and irrigation, the canals were dried with paper points and filled with one of four sealers: AH Plus, iRoot SP, MTA and MTA Fillapex. Roots were sectioned, and push-out tests were performed. The values of bond strength were analysed using the Kruskal-Wallis test. Mann-Whitney with Bonferroni correction was used to isolate the differences. The alpha-type error was set at 0.05 for the analyses. RESULTS: All specimens had measurable adhesion to root dentine and no premature failure occurred. There were significant differences amongst materials (P = 0.000). MTA-filled specimens had higher push-out bond strength values (P = 0.000). AH Plus had significantly higher bond strength than both Fillapex and iRoot SP (P = 0.000). Both Fillapex and iRoot SP had the lowest push-out bond strength amongst all experimental groups (P = 0.000). No difference occurred between the two calcium silicate-based root canal sealers (P = 0.265). CONCLUSION: The adhesion to root dentine associated with newer calcium silicate-based sealers was compromised even when well-monitored laboratory conditions were used.

Genetic and non-genetic factors that increase the risk of non-syndromic cleft lip and/or palate development.

OBJECTIVES: We investigated the relationship between non-syndromic cleft lip/palate (NSCLP) and polymorphisms in methylenetetrahydrofolate reductase (MTHFR), methionine synthase (MTR), methionine synthase reductase (MTRR), and RFC1, as well as the corresponding interactions with environmental factors. SUBJECTS AND METHODS: One hundred and forty NSCLP patients and their mothers, as well as 175 control individuals and their mothers, were recruited. Information regarding smoking and alcohol consumption was recorded. Blood samples were obtained in order to measure serum folate and cobalamin, as well as, plasma total homocysteine concentrations and to extract DNA. Polymorphisms in MTHFR(677C>T and 1298A>C), MTR(2756A>G), MTR(66A>G), and RFC1(80A>G) were analyzed by PCR-restriction fragment length polymorphism. RESULTS: Among the patients, 59.5% had cleft lip and palate, 22.0% had cleft palate, and 18.5% had cleft lip only. Maternal alcohol consumption and reduced folic acid concentrations in both children and mothers (P < 0.001 and P = 0.003, respectively) were risk factors for NSCLP. Patients and their mothers carrying the MTHFR 667T allele showed lower serum folate than CC (P = 0.011 and P = 0.030, respectively). Mothers who carried the MTHFR 1298C allele exhibited increased risk of having a child with NSCLP, after adjusting for alcohol consumption (OR: 1.75, 95% CI: 1.03-2.99, P = 0.038). CONCLUSIONS: Reduced folic acid levels, alcohol consumption, and the MTHFR 677T and 1298C alleles may have contributed to NSCLP development in this sample population from Rio Grande do Norte.

Living with inborn errors of cholesterol biosynthesis: lessons from adult patients.

In the last decades, nine inherited errors of the distal part of cholesterol biosynthesis have been recognized. Affected patients present complex malformation syndromes involving different organs and systems with variable degrees of severity. We report on the phenotype evolution of three patients with enzymatic defects at three distinct steps of such pathway: Smith-Lemli-Opitz syndrome, X-linked dominant chondrodysplasia punctata type 2 and congenital hemidysplasia with ichthyosiform erythroderma and limb defects syndrome. The patients' natural history, from childhood to adulthood, is thoroughly described in order to contribute for a better knowledge of these diseases. Our ultimate goals are to contribute for a better characterization of the long-term course of these metabolic disorders and for the recognition of such diseases in older patients.

Liver transplantation prevents progressive neurological impairment in argininemia.

Argininemia is a rare hereditary disease due to a deficiency of hepatic arginase, which is the last enzyme of the urea cycle and hydrolyzes arginine to ornithine and urea. The onset of the disease is usually in childhood, and clinical manifestations include progressive spastic paraparesis and mental retardation. Liver involvement is less frequent and usually not as severe as observed in other UCDs. For this reason, and because usually there is a major neurological disease at diagnosis, patients with argininemia are rarely considered as candidates for OLT despite its capacity to replace the deficient enzyme by an active one. We report on long-term follow-up of two patients with argininemia. Patient 1 was diagnosed by the age of 20 months and despite appropriate conventional treatment progressed to spastic paraparesis with marked limp. OLT was performed at 10 years of age with normalization of plasmatic arginine levels and guanidino compounds. Ten years post-OLT, under free diet, there is no progression of neurological lesions. The second patient (previously reported by our group) was diagnosed at 2 months of age, during a neonatal cholestasis workup study. OLT was performed at the age of 7 years, due to liver cirrhosis with portal hypertension, in the absence of neurological lesions and an almost-normal brain MRI. After OLT, under free diet, there was normalization of plasmatic arginine levels and guanidino compounds. Twelve years post-OLT, she presents a normal neurological examination. We conclude that OLT prevents progressive neurological impairment in argininemia and should be considered when appropriate conventional treatment fails.

MSX1 gene polymorphisms in non-syndromic cleft lip and/or palate.

OBJECTIVE: The aim of this study was to investigate the contribution of 6 polymorphic variants of the MSX1 gene in non-syndromic cleft lip and/or palate (NSCL/P). METHODS: Three hundred and fifty-eight individuals (158 NSCL/P cases and 200 controls) were genotyped by TaqMan allelic discrimination using predesigned SNP assays. Statistical analyses were conducted using the software spss 15.0 and the r statistical suite. Haplotype block structure and haplotype frequencies were determined using the Haploview. A P-value of 0.05 and confidence interval of 95% were used for all of statistical tests. RESULTS: The patients with non-syndromic cleft lip and/or palate were characterized by similar distribution of MSX1 genotypes and allele in comparison to subjects without oral clefts (P > 0.05). Two haplotype blocks were constructed with polymorphisms of MSX1 gene and haplotypes formed showed a similar frequency in patients with and without oral clefts. CONCLUSIONS: The present study provides no evidence that MSX1 polymorphisms (rs3775261, rs1042484, rs12532, rs6446693, rs4464513 and rs1907998) play a major role in NSCL/P.

Clinical, biochemical and molecular characterization of cystinuria in a cohort of 12 patients.

Cystinuria is a rare autosomal inherited disorder characterized by impaired transport of cystine and dibasic aminoacids in the proximal renal tubule. Classically, cystinuria is classified as type I (silent heterozygotes) and non-type I (heterozygotes with urinary hyperexcretion of cystine). Molecularly, cystinuria is classified as type A (mutations on SLC3A1 gene) and type B (mutations on SLC7A9 gene). The goal of this study is to provide a comprehensive clinical, biochemical and molecular characterization of a cohort of 12 Portuguese patients affected with cystinuria in order to provide insight into genotype-phenotype correlations. We describe seven type I and five non-type I patients. Regarding the molecular classification, seven patients were type A and five were type B. In SLC3A1 gene, two large genomic rearrangements and 13 sequence variants, including four new variants c.611-2A>C; c.1136+44G>A; c.1597T (p.Y533N); c.*70A>G, were found. One large genomic rearrangement was found in SLC7A9 gene as well as 24 sequence variants including 3 novel variants: c.216C>T (p.C72C), c.1119G>A (p.S373S) and c.*82C>T. In our cohort the most frequent pathogenic mutations were: large rearrangements (33.3% of mutant alleles) and a missense mutation c.1400T>C (p.M467T) (11.1%). This report expands the spectrum of SLC3A1 and SLC7A9 mutations and provides guidance in the clinical implementation of molecular assays in routine genetic counseling of Portuguese patients affected with cystinuria.

Quantitative analysis of five sterols in amniotic fluid by GC-MS: application to the diagnosis of cholesterol biosynthesis defects.

Cholesterol and its precursors, namely 7-dehydrocholesterol, desmosterol and lathosterol are important biochemical markers of cholesterol biosynthesis, and their quantification in body fluids is useful for the diagnosis of cholesterol biosynthesis pathway disorders. A rapid and sensitive gas chromatographic-mass spectrometric method was developed and validated for quantitative analysis of five sterols (cholesterol, 7-dehydrocholesterol, desmosterol, lathosterol and sitosterol) in amniotic fluid. The method was linear for all compounds (r(2)>0.99), and intra and inter-assay coefficients of variation were typically below 5%, and inaccuracy was within a +/-12% interval. The method was applied to 330 amniotic fluid samples, grouped by gestational age between 13 and 22 weeks of pregnancy, in order to establish reference intervals for sterols in this specimen. The obtained concentrations (mumol/L) for each sterol was as follows: 22.1758+/-4.2716 at 13 weeks and 78.5082+/-12.9041 at 22 weeks for cholesterol; 0.0039+/-0.0007 at 13 weeks and 0.1150+/-0.0212 at 22 weeks for 7-dehydrocholesterol; 0.1562+/-0.0406 at 13 weeks and 0.7691+/-0.0821 at 22 weeks for desmosterol; 0.0272+/-0.0035 at 13 weeks and 0.8551+/-0.1791 at 22 weeks for lathosterol; and 0.0404+/-0.0039 at 13 weeks and 0.2326+/-0.0386 at 22 weeks for sitosterol. The method was also applied to one pathological sample that showed decreased levels of cholesterol, and higher concentration of 7-dehydrocholesterol, which is consistent with a 7-dehydrocholesterol-reductase deficiency. Our results showed that as long as pregnancy goes on, the concentrations of cholesterol and precursors increase in amniotic fluid, which is related to the increased need for cholesterol by the fetus. The reference range of each sterol in amniotic fluid was calculated at different gestational ages and will be useful for the interpretation and validation of biochemical prenatal diagnosis of inborn errors of sterol biosynthesis.

Electrochemical preparation of overlapped porous layers on anodic alumina.

In this paper, we report the development of a new architecture on porous anodic alumina using the conventional two-step anodization method. The samples prepared in two identical steps using galvanostatic anodization exhibited two porous layers overlapped with distinct pore area distributions. The effects from the first anodization time and temperature on this different morphology were assessed using Factorial Design. The chemical removal time of the oxide formed during the first anodization was not relevant for the overlapped porous structure. The most important factor was the time of the first anodization required for formation of stable patterns on the substrate, which would be reproduced in the second anodization. A pore mismatch appeared because under galvanostatic control the changes in the actual area become important, which is not the case for sample preparation under potentiostatic control where the current density is adjusted according to the new boundary condition. The new architecture with mismatching layers may open the way for further applications of porous alumina as template for nanomaterial.

Early-onset hyperargininaemia: a severe disorder?

UNLABELLED: Hyperargininaemia is a rare inborn error of metabolism due to a defect in the final step of the urea cycle. Infantile onset is the most common presentation with recurrent vomiting and psychomotor delay associated with spastic paraparesis; chronic hyperammonaemia is often overlooked. Neonatal and early-onset presentations are very uncommon and their clinical course not well-described. We report on a 3-week-old hyperargininaemic girl who presented with neurological deterioration associated with liver failure and 47-day ammonia intoxication before diagnosis could be made and treatment started. Despite appropriate but delayed treatment, our patient exhibited severe psychomotor delay at age 1 year. CONCLUSION: Early identification and management of this rare but potentially treatable affection is crucial as delayed management may result in poor neurological outcome.

Sulfated galactofucan from Lobophora variegata: anticoagulant and anti-inflammatory properties.

Sulfated polysaccharides (fucans and fucoidans) from brown algae show several biological activities, including anticoagulant and anti-inflammatory activities. We have extracted a sulfated heterofucan from the brown seaweed Lobophora variegata by proteolytic digestion, followed by acetone fractionation, molecular sieving, and ion-exchange chromatography. Chemical analyses and 13C-NMR and IR spectroscopy showed that this fucoidan is composed of fucose, galactose, and sulfate at molar ratios of 1 : 3 : 2. We compared the anticoagulant activity of L. variegata fucoidan with those of a commercial sulfated polysaccharide (also named fucoidan) from Fucus vesiculosus and heparin. The experimental inflammation models utilized in this work revealed that fucoidan from L. variegata inhibits leukocyte migration to the inflammation site. Ear swelling caused by croton oil was also inhibited when sulfated polysaccharides from F. vesiculosus and L. variegata were used. The precise mechanism of different action between homo- and heterofucans is not clear; nevertheless, the polysaccharides studied here may have therapeutic potential in inflammatory disorders.

Humoral and cellular immune responses to Blomia tropicalis and concanavalin A-binding fractions in atopic patients.

Blomia tropicalis, Dermatophagoides pteronyssinus and D. farinae are prevalent house dust mites. Concanavalin A-binding components derived from B. tropicalis (Bt-ConA extract) are highly immunogenic in allergic diseases. The aim of the present study was to evaluate the humoral and cellular immune responses to B. tropicalis in mite-sensitized patients. A total of 137 patients with allergic rhinitis with/without asthma and 109 non-atopic subjects were selected and analyzed by the skin prick test, and for total serum IgE and specific IgE levels to both Bt-total and Bt-ConA extracts, their proliferative response and cytokine (IFN-gamma and IL-5) production by peripheral blood mononuclear cells (PBMC) stimulated with both extracts. Skin prick test showed that 70% of the patients were sensitized to Bt (Bt+) and similar levels of specific IgE to Bt-total and Bt-ConA extracts were demonstrable in Bt+ patients. Significant PBMC proliferation was observed in response to Bt-total extract in Bt+, but not in Bt- patients and non-atopic subjects (P < 0.001). Bt-ConA extract induced increased proliferative responses in all patient groups compared to medium alone (P < 0.05), but these responses were significantly decreased in the presence of the mannopyranoside ConA inhibitor (P < 0.05). Significant IFN-gamma production was observed after Bt-ConA stimulation of Bt+ patients (P < 0.05), while Bt-total extract had no effect. IL-5 production was consistently detected in Bt+ patients after allergen-specific stimulation or with no stimulus, indicating that PBMC from allergic patients are prone to produce Th2 profile cytokines, spontaneously or inductively by allergen restimulation. These data showed that ConA-binding components isolated from B. tropicalis may contain relevant antigens that are involved in both humoral and cellular immune responses. However, without an additional purification procedure to eliminate the residual contamination with ConA, its use in immunotherapeutic procedures cannot be recommended.

Humoral and cellular immune responses to Blomia tropicalis and concanavalin A-binding fractions in atopic patients

Blomia tropicalis, Dermatophagoides pteronyssinus and D. farinae are prevalent house dust mites. Concanavalin A-binding components derived from B. tropicalis (Bt-ConA extract) are highly immunogenic in allergic diseases. The aim of the present study was to evaluate the humoral and cellular immune responses to B. tropicalis in mite-sensitized patients. A total of 137 patients with allergic rhinitis with/without asthma and 109 non-atopic subjects were selected and analyzed by the skin prick test, and for total serum IgE and specific IgE levels to both Bt-total and Bt-ConA extracts, their proliferative response and cytokine (IFN-ã and IL-5) production by peripheral blood mononuclear cells (PBMC) stimulated with both extracts. Skin prick test showed that 70 percent of the patients were sensitized to Bt (Bt+) and similar levels of specific IgE to Bt-total and Bt-ConA extracts were demonstrable in Bt+ patients. Significant PBMC proliferation was observed in response to Bt-total extract in Bt+, but not in Bt- patients and non-atopic subjects (P < 0.001). Bt-ConA extract induced increased proliferative responses in all patient groups compared to medium alone (P < 0.05), but these responses were significantly decreased in the presence of the mannopyranoside ConA inhibitor (P < 0.05). Significant IFN-ã production was observed after Bt-ConA stimulation of Bt+ patients (P < 0.05), while Bt-total extract had no effect. IL-5 production was consistently detected in Bt+ patients after allergen-specific stimulation or with no stimulus, indicating that PBMC from allergic patients are prone to produce Th2 profile cytokines, spontaneously or inductively by allergen restimulation. These data showed that ConA-binding components isolated from B. tropicalis may contain relevant antigens that are involved in both humoral and cellular immune responses. However, without an additional purification procedure to eliminate the residual contamination with...

Incidence of 3-hydroxy-3-methylglutaryl-coenzyme A lyase (HL) deficiency in Brazil, South America.

3-Hydroxy-3-methylglutaryl-CoA lyase (HL) deficiency (3-hydroxy-3-methylglutaric aciduria, 3-HMG) is a rare autosomal recessive inborn error of metabolism involving the final step of leucine degradation. HL is the key enzyme for the production of glucose-sparing ketone bodies for brain. Positive biochemical findings are metabolic acidosis, hyperammonaemia, and hypoketotic hypoglycaemia in the neonatal period or infancy. In the present study we report 15 Brazilian patients with HL deficiency and present their clinical and biochemical findings. Urine from all patients contained large amounts of 3-hydroxy-3-methylglutaric, 3-methylglutaconic, 3-hydroxyisovaleric and 3-methylglutaric acids, and 3-methylcrotonylglycine was also observed in 13 patients. The main features at clinical presentation were hypoglycaemia (12 patients), seizures (10 patients), metabolic acidosis (9 patients), vomiting (6 patients), and hepatomegaly (5 patients). All but two patients were of Portuguese ancestry. HL deficiency comprised 7.3% of total organic acidurias detected in our laboratory during a 13-year time span, indicating a high incidence of this disorder in Brazil. Limited molecular characterization (4/15 patients only) revealed two mutations common for individuals of Portuguese/Spanish (Iberian Peninsula) ancestry (E37X and V168fs(-2)). Our findings increase the number of HL-deficient patients and reinforce the characteristic phenotypic picture of the disease. Effective dietary interventions based on mild protein restriction and avoidance of fasting and possibly alternative C5 ketone body generating therapy for this disorder may provide further impetus and rationale for expanded newborn screening of HL deficiency.

Responses of IgE, IgG1, and IgG4 to concanavalin A-binding Blomia tropicalis antigens in allergic patients.

Blomia tropicalis (Bt) and Dermatophagoides pteronyssinus (Dp) are the prevalent house dust mites in tropical countries and are associated with allergic diseases. Glycosylated antigens are highly immunogenic and involved in different pathologies. We evaluated the presence of IgE, IgG1, and IgG4 to concanavalin A-binding antigens (Bt-Con-A) isolated from Bt-total extract in sera of allergic and non-allergic subjects. Bt-total and Bt-Con-A extracts were evaluated by SDS-PAGE and ELISA for reacting with IgE, IgG1, and IgG4 in sera of 121 patients with allergic rhinitis and 36 non-allergic individuals. All subjects were skin prick tested with Bt-total extract and inhibition tests were performed for IgE, IgG1, and IgG4 using both extracts (Bt-total and Bt-Con-A). Skin prick test showed that 58% of the patients were sensitized to Bt (Bt+), with 52% reactive to both mites (Bt and Dp) and 6% to Bt only. A broad spectrum of proteins (14-152 kDa) was visualized in Bt-total and components >27 kDa for the Bt-Con-A extract. ELISA showed a similar profile of IgE, IgG1 and IgG4 levels in response to Bt-total and Bt-Con-A extracts in different groups, although Bt+ patients showed a lower IgG4 reactivity to Bt-Con-A extract. Specific IgG1 levels were higher in Bt+ patients than in control subjects, and IgG4 levels showed no significant difference among groups. ELISA inhibition showed a partial IgE and total IgG1 and IgG4 cross-reactivity with Dp extract for Bt-total and Bt-Con-A extracts. We conclude that Con-A-binding components isolated from Bt constitute major allergens and are involved in both allergen sensitization (IgE response) and homeostasis maintenance (IgG1 and IgG4 responses).

Responses of IgE, IgG1, and IgG4 to concanavalin A-binding Blomia tropicalis antigens in allergic patients

Blomia tropicalis (Bt) and Dermatophagoides pteronyssinus (Dp) are the prevalent house dust mites in tropical countries and are associated with allergic diseases. Glycosylated antigens are highly immunogenic and involved in different pathologies. We evaluated the presence of IgE, IgG1, and IgG4 to concanavalin A-binding antigens (Bt-Con-A) isolated from Bt-total extract in sera of allergic and non-allergic subjects. Bt-total and Bt-Con-A extracts were evaluated by SDS-PAGE and ELISA for reacting with IgE, IgG1, and IgG4 in sera of 121 patients with allergic rhinitis and 36 non-allergic individuals. All subjects were skin prick tested with Bt-total extract and inhibition tests were performed for IgE, IgG1, and IgG4 using both extracts (Bt-total and Bt-Con-A). Skin prick test showed that 58 percent of the patients were sensitized to Bt (Bt+), with 52 percent reactive to both mites (Bt and Dp) and 6 percent to Bt only. A broad spectrum of proteins (14-152 kDa) was visualized in Bt-total and components >27 kDa for the Bt-Con-A extract. ELISA showed a similar profile of IgE, IgG1 and IgG4 levels in response to Bt-total and Bt-Con-A extracts in different groups, although Bt+ patients showed a lower IgG4 reactivity to Bt-Con-A extract. Specific IgG1 levels were higher in Bt+ patients than in control subjects, and IgG4 levels showed no significant difference among groups. ELISA inhibition showed a partial IgE and total IgG1 and IgG4 cross-reactivity with Dp extract for Bt-total and Bt-Con-A extracts. We conclude that Con-A-binding components isolated from Bt constitute major allergens and are involved in both allergen sensitization (IgE response) and homeostasis maintenance (IgG1 and IgG4 responses).

Mutational spectrum of classical galactosaemia in Spain and Portugal.

Classical galactosaemia is an autosomal recessive inherited metabolic disorder due to deficient galactose-1-phosphate uridyltransferase (GALT). Over 180 different base changes and disease-causing mutations have been reported in the GALT gene. Mutation p.Q188R was found to be the most common molecular defect among caucasian classical galactosaemia patients. We have characterized the spectrum of GALT mutations in a group of 51 Spanish families and 32 Portuguese families with this disease. p.Q188R is also the most prevalent mutation in the Spanish and Portuguese population, accounting for 50% and 57.8% of galactosaemic alleles, respectively. An additional 15 mutations were also identified in Spanish patients, four of which were novel: p.D28H, p.S181A, c.658dupG and c.377+53_1059+87del. In the Portuguese population, 11 different mutations were found, three of which were novel: p.R33H, p.P185S, and p.S192G. The differences observed between the genotypes identified in Portuguese and Spanish galactosaemic populations are notable. Only mutations p.Q188R, p.R148Q and c.820+13g>a were identified in both populations. In spite of the geographical proximity of Spain and Portugal, it seems that they have received genetic influences from different populations. The repeated migrations that occurred in the Iberian Peninsula throughout centuries may explain such variability.

Novel L2HGDH mutations in 21 patients with L-2-hydroxyglutaric aciduria of Portuguese origin.

We studied 21 patients, from 18 families, with L-2-hydroxyglutaric aciduria (L-2-HGA), a rare neurometabolic disorder with a homogeneous presentation: progressive neurodegeneration with extrapyramidal and cerebellar signs, seizures, and subcortical leukoencephalopathy. Increased levels of L-2-hydroxyglutaric acid in body fluids proved the diagnosis of L-2-HGA in all 21 patients. We analyzed the L-2-HGA gene (L2HGDH), recently found to be mutated in consanguineous families with L-2-HGA, and identified seven novel mutations in 15 families. Three mutations appeared to be particularly prevalent in this Portuguese panel: a frameshift mutation (c.529delC) was detected in 12 out of 30 mutant alleles (40%), a nonsense mutation (c.208C>T; p.Arg70X) in 7/30 alleles (23%), and a missense mutation (c.293A>G; p.His98Arg) in four out of 30 mutant alleles (13%), suggesting that common origin may exist. Furthermore, two novel missense (c.169G>A; p.Gly57Arg, c.1301A>C; p.His434Pro) and two splice error (c.257-2A>G, c.907-2A>G) mutations were found. All the mutations presumably lead to loss-of-function with no relationship between clinical signs, progression of the disease, levels of L-2-HGA and site of the mutation. In the three remaining families, no pathogenic mutations in the L-2-HGA were found, which suggests either alterations in regulatory regions of the gene or of its intervening sequences, compound heterozygosity for large genomic deletion and, or further genetic heterogeneity.

[Hypoglycaemia without ketosis. A case report]. / Hipoglucemia sin cetosis. Caso clínico.

INTRODUCTION: Long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency (LCHADD) is a rare disease, inherited as autosomal-recessive trait, with variable clinical presentation including severe hypoglycaemia, cardiomyopathy, sudden infant death, progressive liver failure, 'Reye like' syndrome, neuromyopathy, muscle weakness and rhabdomyolysis. CASE REPORT: We report a 3 years old male patient admitted to our emergency department with vomiting, hypotonia and prostration, after a common respiratory infection. The presence of hypoketotic hypoglycaemia and elevated liver enzymes in the admission motivated a metabolic study. We found an abnormal low lactate/pyruvate ratio, decreased serum carnitine and dicarboxylic aciduria leading to the diagnosis of a fatty acid oxidation disorder (LCHADD). The molecular study of HADHA gene revealed homozygosity for the G1528C mutation in the patient DNA, and heterozygosity in both parents. CONCLUSIONS: The diagnosis of a fatty acid oxidation disorder must be considered in the presence of vomiting associated with excessive prostration specially if there is hypoketotic hypoglycaemia or familiar sudden infant death history. Physicians should be aware about these conditions and for the importance of measuring both glycaemia and ketone bodies during the evaluation of high risk situations.

Molecular studies in Portuguese patients with Smith-Lemli-Opitz syndrome and report of three new mutations in DHCR7.

Smith-Lemli-Opitz syndrome (SLO) is an autosomal recessive disorder characterised by craniofacial dysmorphism, mental retardation, multiple congenital anomalies, and increased levels of 7-dehydrocholesterol (7-DHC) in body tissues and fluids. SLO is caused by mutations in the DHCR7 gene which encodes 7-dehydrocholesterol reductase, the last enzyme of cholesterol biosynthesis pathway. In our investigation, we screened 682 dysmorphic/mentally retarded Portuguese patients for abnormal levels of 7-DHC in blood by UV spectrometry. We identified six unrelated patients with SLO (0.87% of total). Mutational analysis of the DHCR7 gene led to the identification of seven distinct mutations, three of which are new (F174S, H301R, and Q98X). The common IVS8-1G > C and T93M variants together with the H301R accounted for 70% of the all SLO alleles in our population. Our findings contribute to the variegate array of pathological changes in the DHCR7 gene among different European populations.

The E37X is a common HMGCL mutation in Portuguese patients with 3-hydroxy-3-methylglutaric CoA lyase deficiency.

3-Hydroxy-3-methylglutaric aciduria (OMIM 246450) is an autosomal recessive inborn error of the final step of leucine catabolic and ketogenic pathways, caused by deficiency of the enzyme 3-hydroxy-3-methylglutaryl CoA lyase (HL, HMGCL, EC 4.1.3.4). Clinically, deficiency of the enzyme results in metabolic acidosis, hyperammonemia, and infantile hypoketotic hypoglycaemia usually presenting during the first year of life with vomiting, lethargy, hypotonia, and sometimes with respiratory distress and coma. HL deficiency is relatively common in Arabic populations but seems to be rare in Europe. Our recent experience suggests that HL deficiency is the most frequent organic aciduria in the Portuguese population. We herein report on the molecular study of the HMGCL gene in 11 cases originated from the Northern area of Portugal. We detected the E37X (c.109G > T) mutation, in 84.1% of the alleles, one allele carried the V168fs(-2) (504_505delCT) and other allele the novel D204N (c.610G > A) mutation. The mutation of the last allele remained unidentified. The relatively high frequency of the "common" HMGCL Portuguese mutation makes useful the development of a rapid and specific molecular confirmation of new cases with HL deficiency in our country.