Detection of enteric campylobacteriosis in children.

Campylobacter fetus subsp. jejuni was recovered as the sole bacterial pathogen from 31% of 0- to 8-month-old children with acute gastroenteritis and from 5% of asymptomatic children (P less than 0.05). In children 8 to 24 months old, the respective recovery rates were 38 and 40%. With the exception of one case of simultaneous bacteremia, the clinical course of the symptomatic infection was benign and rarely lasted more than a week. The isolates were sensitive to most commonly used antibiotics. Several isolates shared antigenic determinants with C. fetus subsp. intestinalis. A bacteriophage specific for C. fetus subsp. jejuni lysed 73% of the strains. Several phage-resistant isolates carried a phage that lysed the stock strain of C. fetus subsp. jejuni (NADC 917).     

Circulating antibodies to peripheral nerve in American trypanosomiasis (Chagas' disease).

An antibody reacting with Schwann sheaths of myelinated somatic and unmyelinated autonomic peripheral nerve was found in sixty-one out of seventy-one chronic, and nine out of ten acute, Chagas' disease sera. Indirect immunofluorescence (IFL) was carried out on rat, mouse and human somatic nerves and rat sympathetic nerves with initial serum dilutions of 1 : 10, and the staining reached a final titre of 1 : 320 in some cases. The antibodies fixed complement and were absorbed out by lyophilized epimastigotes of T. cruzi. Lipid extraction of the tissue sections enhanced the staining of myelinated nerve, whereas unfixed unmyelinated sympathetic nerve was strongly reactive. Central nervous tissue did not display any positive staining on neurons, glial cells or periaxonal sheaths. Furthermore, by using a double-labelled IFL technique, it was possible to show that a rabbit antiserum raised against guinea-pig spinal cord and the chagasic anti-nerve antibodies reacted with different structures in the rat sciatic nerve. These findings suggest that the reactive antigen(s) could be located on Schwann cells. The majority, but not all, of the chagasic individuals with anti-nerve antibodies also showed the sarcolemmal and endothelial staining (EVI) previously described in Chagas' disease. The possible recognition of Schwann cell antigens by circulating antibodies in Chagas' disease could be relevant, since an autonomic denervation has been postulated as a pathogenic mechanism of cardiomyopathy and megaviscera in this condition.     

Antigen-induced inhibition of human in vitro spontaneous IgE synthesis. I. Factors and kinetic studies.

Peripheral blood mononuclear cells from patients with hypersensitivity to L. perenne and D. pteronyssinus were incubated with specific antigen. They were then cultured for 7 days in the absence of antigen and the IgE contained in the supernatants was determined using an enzyme immunoassay (ELISA). Pre-incubation of the cells with antigen produced an inhibitory effect on the spontaneous IgE synthesis in most of the cases (101 of the 134 individual studied). This inhibition was more pronounced and more frequent in those cultures with an elevated spontaneous production of IgE (3,000-10,000 pg/ml). This effect depended on the dose of antigen and the duration of cell exposure. Both spontaneous IgE production kinetics and antigen-mediated inhibition were studied. A study of the IgE content of the cell pellets indicated that the antigen did not induce inhibition of the IgE release. We therefore believe that the inhibition observed must be due to some kind of IgE synthesis suppression.     

Identification of a gene from Xp21 with similarity to the tctex-1 gene of the murine t complex

Long range physical mapping within the p21 region of the X chromosomeIdentified a CpG rich Island approximately 180 kb centromericto the chronic granulomatous disease (CGD) locus. The segmentsadjacent to the CpG Island hybridized to discrete bands In DNAsof several species and when used to screen retinal cDNA librariesled to the Identification of cDNAs that detected a mRNA of 2.1kb in many tissues. Molecular characterization of correspondinggenomic clones of this novel human gene confirmed the originof the cDNA clones and Indicated a genomic structure with fiveexons spanning a total of 9 kb. The complete cDNA sequence revealedthat this gene contained a putative open reading frame of 116amino acids with a 3' untranslated region of 1.74 kb. The aminoacid sequence shows a high degree of similarity to the predictedproduct of the tctex-1 gene of the mouse t complex. As linkagestudies and patients with deletions have Implicated the Xp21region as containing the retInltls plgmentosa defect (RP3),the gene was assessed as a candidate disease gene In RP3 families.A single base pair polymorphism was Identified within the codingregion but no disease associated changes were found by singlestrand conformational polymorphism and sequencing analysis ofamplified exons of 20 RP patients. Analysis of a dinucleotiderepeat polymorphism within this gene In families affected withRP3 suggested refinement of the RP3 region.     

Novel FARS2 variants in patients with early onset encephalopathy with or without epilepsy associated with long survival

Mitochondrial translation is essential for the biogenesis of the mitochondrial oxidative phosphorylation system (OXPHOS) that synthesizes the bulk of ATP for the cell. Hypomorphic and loss-of-function variants in either mitochondrial DNA or in nuclear genes that encode mitochondrial translation factors can result in impaired OXPHOS biogenesis and mitochondrial diseases with variable clinical presentations. Compound heterozygous or homozygous missense and frameshift variants in the FARS2 gene, that encodes the mitochondrial phenylalanyl-tRNA synthetase, are commonly linked to either early-onset epileptic mitochondrial encephalopathy or spastic paraplegia. Here, we expand the genetic spectrum of FARS2-linked disease with three patients carrying novel compound heterozygous variants in the FARS2 gene and presenting with spastic tetraparesis, axial hypotonia and myoclonic epilepsy in two cases.Subject terms: Metabolic disorders, Mutation     

Outbreak ofPneumocystis carinii pneumonia in a renal transplant unit

The charts for seven renal transplant recipients who developedPneumocystis carinii pneumonia were reviewed. They included six men and one woman transplanted a mean of 150 days before the diagnosis of this infection. Six presented at least one episode of acute graft rejection. Cytomegalovirus pneumonia was diagnosed in six of the patients. All patients were treated with cotrimoxazole. Global mortality was 43 %. In additional to the classic hypothesis of latentPneumocystis carinii reactivation in immunocompromised hosts, this and previous reports of outbreaks strongly suggest either a person-to-person transmission or acquisition from the environment. Molecular typing of isolates could be of value in identifying the source of such outbreaks. Chemoprophylaxis should be more systematically administered to renal transplant patients, co-trimoxazole being the drug of choice.