PCR assay for the detection and the identification of atypical canine coronavirus in dogs

Comparative sequence analysis of the PCR products of the M gene and fragments of the pol1a and pol1b genes of canine coronavirus (CCoV) have demonstrated that two separate clusters of CCoV are present in dogs. This note describes a PCR assay to identify atypical CCoV strains with nucleotide substitutions in the M gene. A total of 177 faecal samples from dogs CCoV positive previously with the PCR assay were analysed. Sixty-two of the 177 samples were amplified with the PCR described in the present study and were thus considered atypical CCoVs. The specificity of the PCR typing assay was confirmed by sequence analysis of the PCR products.     

NEOPLASTIC DISEASE AND DELETION 22q11.2: A MULTICENTRIC STUDY AND REPORT OF TWO CASES

Deletion 22q11.2 is a chromosomal abnormality detected in young patients with clinical manifestations of the DiGeorge/velocardiofacial syndrome. Conotruncal heart defects are also associated with del22q11.2. An association of these cardiac malformations with neoplasias has been observed. Our series includes two cases of malignancies, a hepatoblastoma and a renal-cell carcinoma, arising in children with complex cardiac malformations. The aim of the study was to determine if the deletion at 22q11.2 was present and could be responsible for both pathological processes. Del22q11.2 was identified in both cases. Comparative genomic hybridization revealed terminal gains on chromosomes 1q and Xq and terminal loss on 1p in the hepatoblastoma, and gains in 1p, 12q, 16p, 20q, 22q, and whole chromosome 19 and loss of Xq in the renal-cell carcinoma. Our results confirm a common genetic basis for cardiac malformations, and del22q11.2 presents a risk factor for the development of pediatric tumours.     

Placental and fetal effects of antenatal exposure to antidepressants or untreated maternal depression

Objective: To assess systematically the effects of antidepressants and untreated maternal depression on human placenta and the developing fetus.

Methods: Pertinent medical literature information was identified using MEDLINE/PubMed, SCOPUS and EMBASE. Electronic searches, limited to human studies published in English, provided 21 studies reporting primary data on placental and fetal effects of antidepressant exposure or untreated gestational depression.

Results: The impact of antidepressants and non-medicated maternal depression on placental functioning and fetal biochemical architecture seems to be demonstrated, although its clinical significance remains unclear. More robust data seem to indicate that exposure to either antidepressants or untreated maternal depression may induce epigenetic changes and interfere with the physiological fetal behavior. Two cases of iatrogenic fetal tachyarrhythmia have also been reported.

Conclusions: Future research should clarify the clinical relevance of the impact of antidepressant and untreated maternal depression exposure on placental functioning. Moreover, ultrasound studies investigating fetal responses to antidepressants or maternal depressive symptoms are mandatory. This assessment should be performed during the whole duration of gestational period, when different fetal behavioral patterns become progressively detectable. Analyses of biochemical and epigenetic modifications associated with maternal mood symptoms and antidepressant treatment should also be implemented.     

Hemolytic anemia during pegylated IFN-alpha2b plus ribavirin treatment for chronic hepatitis C: ribavirin is not always the culprit.

A 53-year-old woman admitted to our department for histologically proven chronic hepatitis C had previously been treated with pegylated interferon-alpha2b (PEG-IFN) plus ribavirin. Combination therapy had been withdrawn after 5 weeks because of severe anemia (hemoglobin 8.2 g/dl) despite a reduction in ribavirin dose. A second liver biopsy showed moderate chronic hepatitis with portoportal and portocentral bridges (Ishak score: grading 14/18, staging 4-5/6). Consequently, the patient was retreated with 1.5 microg/kg body weight weekly PEG-IFN and 1000 mg/day ribavirin. Ribavirin was withdrawn about 3 months later because of anemia. After 1 month of PEG-IFN alone, hemoglobin had decreased further to reach 7.9 g/dl; consequently IFN was stopped. An elevated reticulocyte count, indirect bilirubin concentration, and lactic dehydrogenase (LDH) concentration, and a positive direct Coombs test (IgG3, C3d also for panagglutinant irregular antibodies on eluate) led us to diagnose autoimmune hemolytic anemia (AHA). The patient received 1 mg/kg body weight/day prednisone, and all parameters normalized within 20 days. This is the first case of IFN-related AHA during PEG-IFN plus ribavirin therapy. Physicians should be aware that PEG-IFN can be the cause of AHA during a ribavirin-containing regimen for chronic hepatitis C.     

The CTLA-4 gene region of chromosome 2q33 is linked to, and associated with, type 1 diabetes. Belgian Diabetes Registry

Susceptibility to autoimmune insulin-dependent (type 1) diabetes mellitus is determined by a combination of environmental and genetic factors, which include variation in MHC genes on chromosome 6p21 (IDDM1) and the insulin gene on chromosome 11p15 (IDDM2). However, linkage to IDDM1 and IDDM2 cannot explain the clustering of type 1 diabetes in families, and a role for other genes is inferred. In the present report we describe linkage and association of type 1 diabetes to the CTLA-4 gene (cytotoxic T lymphocyte associated-4) on chromosome 2q33 (designated IDDM12). CTLA-4 is a strong candidate gene for T cell- mediated autoimmune disease because it encodes a T cell receptor that mediates T cell apoptosis and is a vital negative regulator of T cell activation. In addition, we provide supporting evidence that CTLA-4 is associated with susceptibility to Graves' disease, another organ- specific autoimmune disease.      

46, XY gonadal dysgenesis: new SRY point mutation in two siblings with paternal germ line mosaicism

Stoppa‐Vaucher S, Ayabe T, Paquette J, Patey N, Francoeur D, Vuissoz J‐M, Deladoëy J, Samuels ME, Ogata T, Deal CL. 46, XY gonadal dysgenesis: new SRY point mutation in two siblings with paternal germ line mosaicism. Familial recurrence risks are poorly understood in cases of de novo mutations. In the event of parental germ line mosaicism, recurrence risks can be higher than generally appreciated, with implications for genetic counseling and clinical practice. In the course of treating a female with pubertal delay and hypergonadotropic hypogonadism, we identified a new missense mutation in the SRY gene, leading to somatic feminization of this karyotypically normal XY individual. We tested a younger sister despite a normal onset of puberty, who also possessed an XY karyotype and the same SRY mutation. Imaging studies in the sister revealed an ovarian tumor, which was removed. DNA from the father's blood possessed the wild type SRY sequence, and paternity testing was consistent with the given family structure. A brother was 46, XY with a wild type SRY sequence strongly suggesting paternal Y‐chromosome germline mosaicism for the mutation. In disorders of sexual development (DSDs), early diagnosis is critical for optimal psychological development of the affected patients. In this case, preventive karyotypic screening allowed early diagnosis of a gonadal tumor in the sibling prior to the age of normal puberty. Our results suggest that cytological or molecular diagnosis should be applied for siblings of an affected DSD individual.     

Pluripotential reprogramming of the somatic genome in hybrid cells occurs with the first cell cycle

The fusion of pluripotent embryonic cells with somatic cells results in reprogramming of the somatic cell genome. Oct4-green fluorescent protein (GFP) transgenes that do not contain the proximal enhancer (PE) region are widely used to visualize reprogramming of the somatic to the pluripotent cell state. The temporal onset of Oct4-GFP activation has been found to occur 40-48 hours postfusion. We asked whether activation of the transgene actually reflects activation of the endogenous Oct4 gene. In the current study, we show that activation of an Oct4-GFP transgene that contains the PE region occurs within 22 hours of fusion. In addition, demethylation of the Oct4-GFP transgene and that of the endogenous Oct4 and Nanog genes was found to occur within 24 hours of fusion. As this timing corresponds with the timing of cell cycle completion in embryonic stem cells and fusion hybrids (approximately 22 hours), we postulate that pluripotential reprogramming of the somatic cell genome begins during the first cell cycle after the fusion of a somatic cell with a pluripotent cell and has been completed by day 2 postfusion.