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Biomedical subjects

J Frenkel

Publications and source records attributed to J Frenkel.

At least 19 recordsLinked to original sources

[Acute hemorrhagic edema in children: excellent prognosis].

In 2 young children, boys aged 8 and 14 months, who were referred with fever and typical concentric skin lesions and oedema (except for on the trunk), acute haemorrhagic oedema was diagnosed. This is a benign leucocytoclastic vasculitis of the skin accompanied by oedema, which affects children between birth and 36 months of age. It is often preceded by an infection or vaccination. As a rule, recovery is complete.

Acute Disease↗

Hereditary periodic fever syndromes.

Hereditary periodic fever syndromes are defined by recurrent attacks of generalised inflammation for which no infectious or auto-immune cause can be identified. For most of these disorders, the molecular basis has recently been elucidated. This has opened the prospect of novel therapeutic approaches. Familial Mediterranean fever (FMF) is caused by mutations in the MEFV gene. Pathogenesis is poorly understood. The clinical severity is in part related to the mutations involved. Tumour necrosis factor receptor-1-associated periodic syndrome (TRAPS) is caused by mutations in the TNFRSF1A gene. This results in decreased serum levels soluble TNF-receptor leading to inflammation due to unopposed TNF-alpha action. Results of treatment with recombinant TNF-receptor analogues are promising. The hyper IgD periodic fever syndrome (HIDS) is caused by mutations in the MVK gene, leading to mevalonate kinase deficiency. The pathogenesis remains unclear. Muckle-Wells syndrome (MWS) and familial cold urticaria (FCU) are probably allelic disorders. The gene has been located, but not identified.

Algorithms↗

Organization of the mevalonate kinase (MVK) gene and identification of novel mutations causing mevalonic aciduria and hyperimmunoglobulinaemia D and periodic fever syndrome.

Mevalonic aciduria (MA) and hyperimmunoglobulinaemia D and periodic fever syndrome (HIDS) are two autosomal recessive inherited disorders both caused by a deficient activity of the enzyme mevalonate kinase (MK) resulting from mutations in the encoding MVK gene. Thus far, disease-causing mutations only could be detected by analysis of MVK cDNA. We now describe the genomic organization of the human MVK gene. It is 22 kb long and contains 11 exons of 46 to 837 bp and 10 introns of 379 bp to 4.2 kb. Three intron-exon boundaries were confirmed from natural splice variants, indicating the occurrence of exon skipping. Sequence analysis of 27 HIDS and MA patients confirmed all previously reported genotypes based on cDNA analysis and identified six novel nucleotide substitutions resulting in missense or nonsense mutations, providing new insights in the genotype/phenotype relation between HIDS and MA.

Alternative Splicing↗

Transvaginal sonographic assessment of cervical length changes during triplet gestation.

The current study aimed to evaluate the contribution of transvaginal sonography (TVS) for monitoring cervical changes during the second half of triplet gestation. Forty-five pregnant women with triplets pregnancies were prospectively scanned by TVS from approximately 26 weeks gestation and were longitudinally followed-up until delivery. Based on a receiver-operating curve it was found that a cervical length of 25 mm is the most accurate parameter (94% sensitivity and 45% specificity) for predicting premature delivery < or =33 gestational weeks. Thus, a single cervical length measurement of < or =25 mm at 26 weeks gestation correlated well with premature delivery at < or =33 weeks (chi(2); P = 0.002). Using the linear regression model, a mathematical equation [(Week of delivery = 27.4 + 1.6 x cervical length; R(2) = 0.46; P = 0.01)] for predicting the gestational age of delivery (dependent variable) was determined based on mid-gestation cervical measurements (predictors). In parturient women with triplet gestation, TVS assessment of the uterine cervix offers insight into the cervical status and provides valuable information for prenatal care. This includes both monitoring the cervical changes throughout third trimester as well as predicting the likelihood of premature delivery.

Adult↗

Clinical and molecular variability in childhood periodic fever with hyperimmunoglobulinaemia D.

OBJECTIVES: The hyperimmunoglobulinaemia D and periodic fever syndrome (HIDS) was found recently to be caused by a deficiency of mevalonate kinase (MK). The aim of this study was to examine whether a relationship exists between the clinical expression of HIDS and the extent of MK deficiency. METHODS: The medical records of children diagnosed with HIDS were reviewed for clinical features and serum immunoglobulin values. The mevalonic acid excretion in urine and MK enzyme activity in patients' cells were measured and the cDNA of the MVK gene was sequenced. RESULTS: Fifteen patients with recurrent fever and raised serum immunoglobulin (Ig) D were included. Their clinical features varied. Eleven patients had a deficiency of MK, caused by mutations in the MVK gene. One mutation (V377I) was common to all 11 patients. Nine patients were compound heterozygotes for V377I and various other MVK mutations. There was no apparent relationship between the observed mutations and the clinical features. Surprisingly, four boys had normal MK activity and no MVK mutations. CONCLUSIONS: Most HIDS patients have mutations in the MVK gene. The clinical variability observed cannot be explained by genotypic differences. Periodic fever and elevated IgD can result from other, still unknown, causes. Hence, testing for MK deficiency is necessary in patients with unexplained periodic fever.

Child↗

Serum levels of inhibin B, unlike inhibin A and activin A, are not altered in women with preeclampsia.

PROBLEM: To investigate whether inhibin A, inhibin B, and activin A serum levels are altered in women with preeclampsia. METHOD OF STUDY: Serum samples of 20 women with preeclampsia (study group) and 20 normotensive pregnant women, matched for maternal and gestational age and parity, were assayed for inhibin A, inhibin B and activin A by specific enzyme-linked immunosorbent assay. RESULTS: Median serum concentrations of inhibin A and activin A were significantly higher among women with preeclampsia than in women with normotensive pregnancies, while inhibin B levels were comparable in both groups. Activin A levels were positively correlated with those of inhibins A and B, and inhibin A levels were positively correlated with diastolic blood pressure and inhibin B concentration in the study group. CONCLUSIONS: Inhibin A and activin A, but not inhibin B, serum levels are markedly increased in women with preeclampsia. These hormones might serve as an endocrine marker for preeclampsia.

Activins↗

Increased urinary leukotriene E(4) during febrile attacks in the hyperimmunoglobulinaemia D and periodic fever syndrome.

BACKGROUND: The hyperimmunoglobulinaemia D and periodic fever syndrome is a hereditary periodic fever, caused by deficiency of the enzyme mevalonate kinase. It is unclear how this defect leads to recurrent fever episodes. AIM: To assess the involvement of cysteinyl leukotrienes in the pathogenesis of fever attacks as reflected by urinary leukotriene E(4) (LTE(4)) excretion. METHODS: Urinary LTE(4) was measured in seven patients while febrile and afebrile. RESULTS: LTE(4) was raised during fever in all subjects (46-199 nmol/mol creatinine, mean 92; normal <40). Urinary LTE(4) was normal between attacks, as well as in normal children with fever as a result of miscellaneous causes. CONCLUSION: Our results suggest that cysteinyl leukotrienes play a role in the pathophysiology of this disorder. As no effective treatment is yet available, leukotriene receptor antagonists might offer a new therapeutic approach for patients with the hyperimmunoglobulinaemia D and periodic fever syndrome.

Adolescent↗

[Identification of the gene for hyper-IgD syndrome: a model of modern genetics].

Hyperimmunoglobulinaemia D and periodic fever syndrome (HIDS) is a rare autosomal recessive disorder. Patients suffer from recurrent attacks (3-6 days) with fever, abdominal distress, lymphadenopathy, skin lesions and arthralgias. Patients display a constantly elevated serum IgD which serves as a biological marker of the disease. Recently, the gene for HIDS was discovered by two independent groups using positional and functional cloning methods. One group used linkage analysis (positional cloning) and was able to locate the gene for HIDS on the long arm of chromosome 12 (12q24). Mevalonate kinase was an interesting candidate gene because patients with a near complete absence of this enzyme (mevalonic aciduria) do exhibit attacks of fever. Indeed subsequent data showed that there was a decreased enzyme activity due to missense mutations in the mevalonate kinase gene. The other group detected slightly elevated urinary excretion of mevalonic acid during attacks in a HIDS patient (functional cloning). The enzyme activity of mevalonate kinase was lower in cultured cells and sequence analysis identified several missense mutations in cDNA encoding for mevalonate kinase. Mevalonate kinase is a key enzyme in the cholesterol synthesis pathway and it is rather surprising that a defect in the cholesterol metabolism can cause a periodic inflammatory disease such as HIDS.

Biomarkers↗

Accentuated apoptosis in normally developing p53 knockout mouse embryos following genotoxic stress.

In order to identify the alternative pathways which may substitute for the p53 function during embryogenesis, we have focused our studies on p53 -/- normally developing mouse embryos that survived a genotoxic stress. We assumed that under these conditions p53-independent pathways, which physiologically control genomic stability, are enhanced. We found that while p53 +/+ mouse embryos elicited, as expected, a p53-dependent apoptosis, p53-/- normally developing mice exhibited an accentuated p53-independent apoptotic response. The p53-dependent apoptosis detected in p53+/+ embryos, was an immediate reaction mostly detected in the brain, whereas the p53-independent apoptosis was a delayed reaction with a prominent pattern observed in epithelial cells of most organs in the p53-deficient mice only. These results suggest that in the absence of p53-dependent apoptosis, which is a fast response to damaged DNA, p53-independent apoptotic pathways, with slower kinetics, are turned on to secure genome stability.

Animals↗

Mutations in MVK, encoding mevalonate kinase, cause hyperimmunoglobulinaemia D and periodic fever syndrome.

Hyperimmunoglobulinaemia D and periodic fever syndrome (HIDS; MIM 260920) is an autosomal recessive disorder characterized by recurrent episodes of fever associated with lymphadenopathy, arthralgia, gastrointestinal dismay and skin rash. Diagnostic hallmark of HIDS is a constitutively elevated level of serum immunoglobulin D (IgD), although patients have been reported with normal IgD levels. To determine the underlying defect in HIDS, we analysed urine of several patients and discovered increased concentrations of mevalonic acid during severe episodes of fever, but not between crises. Subsequent analysis of cells from four unrelated HIDS patients revealed reduced activities of mevalonate kinase (MK; encoded by the gene MVK), a key enzyme of isoprenoid biosynthesis. Sequence analysis of MVK cDNA from the patients identified three different mutations, one of which was common to all patients. Expression of the mutant cDNAs in Escherichia coli showed that all three mutations affect the activity of the encoded proteins. Moreover, immunoblot analysis demonstrated a deficiency of MK protein in patient fibroblasts, indicating a protein-destabilizing effect of the mutations.

Amino Acid Substitution↗

Renal involvement in Gambian children with cerebral or mild malaria.

Kidney function was studied in 80 Gambian children with cerebral malaria, 73 children with mild malaria, and in 19 children with other febrile illnesses. Serum creatinine was measured, and the excretion in urine of immunoglobulin G, transferrin, albumin and alpha 1 microglobulin was determined. Twenty-five percent of children with cerebral malaria, and 4% of children with mild malaria had an elevated serum creatinine above 62 mumol/l. Increased urinary protein excretion was frequent: 53% of children with cerebral malaria had a glomerulo-tubular pattern of protein excretion, and 46% a tubular pattern. Median albuminuria was 68 mg/l in children with cerebral malaria, 18 mg/l in children with mild malaria, and 9 mg/l in febrile children with other diseases (P < 0.0001). There was no significant association between the proteinuria and height of fever or the degree of parasitaemia, and there was no significant association between death and signs of renal impairment. Renal involvement is common in children with malaria in The Gambia, with prerenal, glomerular, and tubulo-interstitial factors contributing. It is more pronounced in children with cerebral malaria than in those with mild malaria. However, renal dysfunction is relatively mild and does not indicate a worse prognosis.

Alpha-Globulins↗

The role of renal scintigraphy in the diagnosis and follow-up of unilateral ATN after complete bilateral distal ureteral obstruction as a complication of acute appendicitis.

Acute anuria due to bilateral distal ureteral obstruction developed in two boys, ages 7 and 13, several days after appendectomy, without sonographic signs of hydronephrosis or hydroureters. Decompression was achieved after introduction of ureteric stents. This failed on the left side in one patient, and unilateral acute tubular necrosis (ATN) subsequently developed on that side. Although bilateral decompression was successful in the second patient, ATN had already developed on the left side. In both patients, Tc-99m MAG3 renal scintigraphy proved to be an important tool in diagnosing unilateral ATN and for evaluating the recovery from this rare complication.

Acute Disease↗

A trial of artemether or quinine in children with cerebral malaria.

BACKGROUND: Cerebral malaria has a mortality rate of 10 to 30 percent despite treatment with parenteral quinine, a situation that may worsen with the spread of quinine resistance. Artemether is a new antimalarial agent that clears parasites from the circulation more rapidly than quinine, but its effect on mortality is unclear. METHODS: We conducted a randomized, unblinded comparison of intramuscular artemether and intramuscular quinine in 576 Gambian children with cerebral malaria. The primary end points of the study were mortality and residual neurologic sequelae. RESULTS: Fifty-nine of the 288 children treated with artemether died in the hospital (20.5 percent), as compared with 62 of the 288 treated with quinine (21.5 percent). Among the 418 children analyzed at approximately five months for neurologic disease, residual neurologic sequelae were detected in 7 of 209 survivors treated with artemether (3.3 percent) and 11 of 209 survivors treated with quinine (5.3 percent, P = 0.5). After adjustment for potential confounders, the odds ratio for death was 0.84 (95 percent confidence interval, 0.53 to 1.32) in the artemether group, and for residual neurologic sequelae, 0.51 (95 percent confidence interval, 0.17 to 1.47). There were fewer local reactions at the injection site with artemether than with quinine (0.7 percent vs. 5.9 percent, P = 0.001). CONCLUSIONS: Artemether is as effective as quinine in the treatment of cerebral malaria in children.

Antimalarials↗