Occurrence of multiple antibiotic resistance and R plasmids in Enterobacteriaceae isolated from children in the Sudan

The prevalence of resistance to six commonly-used antimicrobial agents in faecal coliforms from children in Khartoum, Sudan was studied. A relatively high prevalence of resistance was found, ranging from 96% of children with isolates resistant to ampicillin to 70% of children with isolates resistant to chloramphenicol. Seventy-seven percent of children had isolates with high-level resistance to trimethoprim (MIC greater than 1000 micrograms/ml). Twenty-nine different resistance patterns were found. Thirty-nine percent of the children had isolates resistant to all six antibiotics studied, and 80% of children had isolates resistant to at least four. Transfer of resistance to each of the antimicrobials, in varying combinations, was demonstrated, but did not occur for all resistance patterns. Plasmid analysis showed plasmids ranging from 160 MDa to 2.8 MDa and isolates contained from one to five plasmids of different sizes. There were no consistent relationships between resistance pattern and plasmid profile, but multiple resistance transfer was mediated commonly by plasmids with a molecular weight of 62 MDa. The high prevalence of potentially transferable antibiotic resistance in gut commensals of children in the Sudan may be of importance in the management of enteric and other infections requiring antimicrobial treatment.     

Interleukin-10 (IL-10) secretion in systemic lupus erythematosus and rheumatoid arthritis: IL-10-dependent CD4+CD45RO+ T cell-B cell antibody synthesis

Interleukin-10 (IL-10) is a major immunoregulatory cytokine and has a multitude of immunomodulatory effects in the immune system. In this study, we have examined the secretion andin vitro function of IL-10 in B cell hyperactivity in antibody production in two common autoimmune diseases, systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). IL-10 was detectable in serum of all active SLE and serum and synovial fluid samples of all RA patients but in none of the normal controls. B cells and CD4+CD45RO+ memory T cells secreted highly enhanced levels of IL-10 in SLE and RA versus normals. Increased IgM and IgG production by B cells-CD4+CD45RO+ T cells in SLE and RA was IL-10 dependent, since neutralization of IL-10 cytokine by anti-IL-10 antibody drastically reduced Ig synthesis in these coculture experiments. B cell hyperactivity in autoantibody production in SLE and RA may be a function of IL-10-dependent CD4+CD45RO+ Th2 cell activation. Therefore, IL-10 may play an important role in highly disturbed immune system and B cell-T cell function in these immune disorders.     

Cytokine profile in systemic lupus erythematosus,rheumatoid arthritis,and other rheumatic diseases

We investigated serum levels of interleukin-6 (IL-6), interferon-gamma (IFN-), and tumor necrosis factor alpha (TNF) from patients with systemic lupus erythematosus (SLE) and its various clinical manifestations of disease and from patients with rheumatoid arthritis (RA) and other rheumatic diseases. The serum levels of IL-6 and IFN- were highly elevated from patients with SLE associated with lymphadenopathy (LN) or nephrotic syndrome (NS). On the contrary, the serum levels of TNF were elevated from most patients with SLE associated with thrombocytopenia (TP). However, serum levels of TNF were in the normal range from patients with SLE associated with NS, LN, or central nervous system disease. Of interest, patients with SLE associated with humoral immunodeficiency disorder, hypogammaglobulinemia, had highly elevated levels of serum IL-6. The concanavalin A-stimulated mononuclear cells (MNC) of patients with SLE associated with TP secreted highly elevated levels of TNF compared to other patient groups. We suggest that abnormal production of various cytokines in SLE is an intrinsic defect of MNC and the immune system that may be the key element for a variety of clinical manifestations of this disease.     

Ploidy profile of morphologically normal squamous epithelium adjacent to high grade cervical intraepithelial neoplasia

We have investigated the ploidy profile of morphologically normal mucosa adjacent to high grade CIN (   n = 16  ) and also from normal cervix ( n = 18). DNA ploidy was assessed using flow cytometry and image analysis. All cases were diploid by both modalities. Our results show that morphologically normal squamous mucosa has a stable ploidy profile even when it lies adjacent to high grade CIN. This finding supports the view that high grade CIN is a neoplastic expansion of transformed cells rather than the result of a field change effect.     

Biallelic Pathogenic GFRA1 Variants Cause Autosomal Recessive Bilateral Renal Agenesis

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Creating oral squamous cancer cells: a cellular model of oral-esophageal carcinogenesis

Immortalization and malignant transformation are important steps in tumor development. The ability to induce these processes from normal human epithelial cells with genetic alterations frequently found in the corresponding human cancer would significantly enhance our understanding of tumor development. Alterations in several key intracellular regulatory pathways (the pRB, p53, and mitogenic signaling pathways and the telomere maintenance system) appear to be sufficient for the neoplastic transformation of normal human cells. Nevertheless, in vitro transformation models to date depend on viral oncogenes, most prominently the simian virus 40 early region, to induce immortalization and malignant transformation of normal human epithelial cells. Here, we demonstrate a transformation model creating oral-esophageal cancer cells by using a limited set of genetic alterations frequently observed in the corresponding human cancer. In a stepwise model, cyclin D1 overexpression and p53 inactivation led to immortalization of oral keratinocytes. Additional ectopic epithelial growth factor receptor overexpression followed by c-myc overexpression as well as consecutive reactivation of telomerase induced by epithelial growth factor receptor sufficed to transform oral epithelial cells, truly recapitulating the development of the corresponding human disease.     

Kudoa azevedoi n. sp. (Myxozoa, Multivalvulida) from the oocytes of the Atlantic horse mackerel Trachurus trachurus (Perciformes, Carangidae) in Tunisian coasts

A new species Kudoa azevedoi sp. n. (Myxozoa, Multivalvulida) is described in Trachurus trachurus Linnaeus, 1758 (Carangidae) from fishing harbors in Tunisian coasts using spore morphology and SSU rDNA sequence data. The parasite occurs only in ovaries within oocytes of mature and immature specimens. Spores are quadrate in shape in apical view with rounded edges, having four shell valves and four symmetrical polar capsules. They are of small sizes and measure 3.5?±?0.41 (3–4.2)?×?4.5?±?0.44 (4–5.2) length by width. The polar capsules are pyriform in shape measuring 1.5?±?0.22 (1.5–2)?×?0.75?±?0.14 (0.5–1)?μm. Infected oocytes are hypertrophied, whitish colored, and filled with mature spores. Plasmodia are tubular and ramified from the inner membrane toward the center of the oocyte. Phylogenetic analysis based on small subunit ribosomal DNA sequences shows the highest similarity (96 %) with the ovary parasite Kudoa ovivora. Some morphological details and spore dimensions support the creation of a new species in the genus Kudoa. Mean prevalence among examined females is of about 55.5 %. It varies between localities and length of fish. The present myxosporea is the second Kudoa species reported in fish ovaries.