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Common variable immunodeficiency (CVID) is considered the most common symptomatic antibody deficiency and, although mainly reported in adults, it may present from childhood. Few data on the impact of TACI defects on the clinical and immunological status of children are available. We screened 42 hypogammaglobulinemia children to investigate the frequency and mutational features of TACI defects. The genetic, clinical and immunological characterization was extended to 31 relatives of 11 children with TACI mutations. Of interest, our analysis showed a considerably higher mutation frequency in hypogammaglobulinemic children (13/42; 31%) than in other cohorts of adult patients. In seven out of nine families with the C104R variant, the prevalence of autoimmunity was significantly higher in C104R heterozygous relatives (8/15; 53%) than in those with no C104R mutation (1/11; 9%). Our data suggest a different impact of TACI mutations, from hypogammaglobulinemia in children to autoimmune disease in adulthood.

We report the first description of visceral leishmaniasis (VL) infection as a harbinger of chronic granulomatous disease (CGD) in a 3-year old child. Although VL is not frequently suspected in CGD patients, our case emphasises the importance of a complete evaluation of the immune system in children presenting with VL in order to exclude underlying immunodeficiency states. As the prognosis of CGD is poor, with high morbidity and mortality, establishing an early diagnosis has important practical implications in the successful treatment of these patients. Following the diagnosis, the patient received Human Leukocyte Antigen (HLA) identical sibling bone marrow transplantation (BMT). The child is now 2 years post-transplant and is in good general conditions with normal blood counts, and evidence of full-donor chimerism in repeated fluorescence in situhybridization (FISH) studies.

The diagnostic potential of endoluminal (endorectal and endovaginal) ultrasound to detect asymptomatic resectable local recurrence after rectal cancer surgery has been assessed in 120 patients: 17 recurrences (14 per cent) were detected. The method showed 97 per cent accuracy, 94 per cent sensitivity and 98 per cent specificity; the positive predictive value was 85 per cent and the negative predictive value was 99 per cent. A longer follow-up is, however, necessary to confirm these results. Of the 17 patients with local recurrence, six were asymptomatic and underwent reoperative surgery. Of the other 11 patients with symptomatic recurrence, only two underwent reoperative surgery.

RanBP1 is a molecular partner of the Ran GTPase, which is implicated in the control of several processes, including DNA replication, mitotic entry and exit, cell cycle progression, nuclear structure, protein import and RNA export. While most genes encoding Ran-interacting partners are constitutively active, transcription of the RanBP1 mRNA is repressed in non proliferating cells, is activated at the G1/S transition in cycling cells and peaks during S phase. We report here that forced expression of the RanBP1 gene disrupts the orderly execution of the cell division cycle at several stages, causing inhibition of DNA replication, defective mitotic exit and failure of chromatin decondensation during the telophase-to-interphase transition in cells that achieve nuclear duplication and chromosome segregation. These results suggest that deregulated RanBP1 activity interferes with the Ran GTPase cycle and prevents the functioning of the Ran signalling system during the cell cycle.

RanBP1 is a molecular partner of the Ran GTPase, which is implicated in the control of several processes, including DNA replication, mitotic entry and exit, cell cycle progression, nuclear structure, protein import and RNA export. While most genes encoding Ran-interacting partners are constitutively active, transcription of the RanBP1 mRNA is repressed in non proliferating cells, is activated at the G1/S transition in cycling cells and peaks during S phase. We report here that forced expression of the RanBP1 gene disrupts the orderly execution of the cell division cycle at several stages, causing inhibition of DNA replication, defective mitotic exit and failure of chromatin decondensation during the telophase-to-interphase transition in cells that achieve nuclear duplication and chromosome segregation. These results suggest that deregulated RanBP1 activity interferes with the Ran GTPase cycle and prevents the functioning of the Ran signalling system during the cell cycle.

The murine Htf9-a/RanBP1 and Htf9-c genes are divergently transcribed from a shared TATA-less promoter. Transcription of both genes is initiated on complementary DNA strands and is controlled by cell cycle-dependent mechanisms. The bidirectional promoter harbors a genomic footprint flanking the major transcription start site of both genes. Transient promoter assays showed that the footprinted element is important for transcription of both genes. Protein-binding experiments and antibody assays indicated that members of the retinoid X receptor family interact with the double-stranded site. In addition, distinct factors interact with single DNA strands of the element. Double-stranded binding factors were highly expressed in liver cells, in which neither gene is transcribed, while single-stranded binding proteins were abundant in cycling cells, in which transcription of both genes is efficient. In vivo S1 analysis of the promoter depicted an S1-sensitive organization in cells in which transcription of both genes is active; S1 sensitivity was not detected in conditions of transcriptional repression. Thus, the same element is a target for either retinoid X receptor factors, or for single-stranded binding proteins, and form distinct complexes in different cellular conditions depending on the DNA conformation in the binding site.

Riassunto Gli. Aa. discutono i problemi clinici della cisti dermoidi ed epidermoidi della fossa cranica posteriore con seno dermico occipitale, ne espongono i dati morfogenetici e i rilievi anatomici, e passano in rassegna le caratteristiche dei pochi casi finora pubblicati.