Vascular graft infection by Staphylococcus aureus: efficacy of cefazolin, teicoplanin and vancomycin prophylaxis protocols in a rat model.

OBJECTIVES: Prophylactic efficiencies of cefazolin, teicoplanin and vancomycin in a dacron graft infection model caused by methicillin-susceptible (MSSA) or -resistant Staphylococcus aureus (MRSA) were investigated. DESIGN: Prospective, randomized, controlled animal study. MATERIALS AND METHODS: Infections were established subcutaneously in the back of rats by implantation of Dacron prostheses followed by topical inoculation onto grafts of MSSA or MRSA. Experimental groups were as follows: Uncontaminated group (control), MSSA- or MRSA-contaminated and untreated groups, MSSA- or MRSA-contaminated groups treated with cefazolin, teicoplanin or vancomycin by one of three regimens (one day, two days, or three days regimen). Grafts were removed 7 days after the implantation and evaluated by using sonication and quantitative blood agar culture. RESULTS: Contaminated groups demonstrated graft infections. Cefazolin, teicoplanin and vancomycin profoundly prevented the graft infections in MSSA- or MRSA-contaminated groups. For each antibiotic regimen, the most effective prevention was achieved by the drugs given as three days regimen. For MSSA and MRSA, the order of the effectiveness was as follows: teicoplanin>vancomycin>cefazolin. CONCLUSION: As a prophylactic agent, teicoplanin seems to be more effective than vancomycin and cefazolin against vascular graft infections caused by MSSA and MRSA in rats.     

Clinical and immunological effects of azithromycin in Behçet''s disease

Background: The aim of this study was to evaluate the effects of azithromycin on mucocutaneous manifestations, oral health and immune response in Behçet's disease (BD). Methods: Eight BD patients with active mucocutaneous symptoms were treated with azithromycin for 4 weeks. Oral health, clinical manifestations and in vitro interleukin (IL)‐12, interferon (IFN)‐γ, IL‐10 and monocyte chemotactic protein (MCP)‐1 responses were evaluated before and after treatment. Results: The number of folliculitic lesions, healing time of oral ulcers and scores of plaque indexes (PLIs) were lower after azithromycin treatment (P < 0.05). Scores of PLIs correlated positively with the healing time of oral ulcers (P = 0.02). Although a trend towards increased stimulated IL‐10 responses with azithromycin was observed, no statistically significant difference was found. Stimulated and unstimulated MCP‐1, IFN‐γ and IL‐12 responses were similar before and after treatment (P > 0.05). Conclusion: Azithromycin was observed to be effective in decreasing folliculitic lesions and fastening the healing time of oral ulcers in BD.     

A mature cystic teratoma in pineal region mimicking parietal encephalocele in a newborn

Objective Teratoma is the most frequently encountered intracranial tumor at birth and constitutes 18–20% of all germ cell tumors. They are usually located in pineal and suprasellar regions. The authors aim to report an extremely unusual presentation, location, and appearance of a teratoma in a newborn. Case report A soft tissue swelling in the vertex was detected in a 1-month-old girl. Neurological examination was normal. A big, cystic–solid lesion beginning from pineal region and extending to the scalp was detected in magnetic resonance imaging. It is interesting to note that cerebral venous angiography showed that the superior sagittal sinus (SSS) was divided into three branches at the level of the lesion and they joined together distally. The tumor was excised totally. Histopathological examination revealed the diagnosis of a mature cystic teratoma. Conclusion A mature cystic teratoma mimicking parietal encephalocele is extremely rare. Germ cell tumors should be kept in mind in the differential diagnosis of all midline lesions with unusual radiographic appearance. Cerebral venous angiography or MR angiography must be performed for the diagnosis and the surgical planning in lesions located near SSS.     

Molecular Characterization of a Full Genome Turkish Hepatitis C Virus 1b Isolate (HCV-TR1): A Predominant Viral Form in Turkey

Based on direct sequencing information from 5UTR and NS5B regions, we identified subtype 1b as a predominant hepatitis C virus genome in Turkey, which affected more than 91% of 79 patients studied. Next, the full genome sequence of a Turkish 1b isolate was obtained by the cloning of polypeptide-encoding region into 7 overlapping fragments. Turkish 1b isolate, which was named HCV-TR1, comprises 9361 nucleotides, including 306 nucleotides of 5UTR, a single long open reading frame of 9033 nucleotides, and 22 nucleotides of 3UTR. When compared to HCV 1b polypeptide sequences available at GenBank, the predicted polypeptide displayed a total of 36 amino acid substitutions, of which 16 was specific for HCV-TR1 isolate. Despite these changes, major structural and functional motifs of HCV proteins were maintained in HCV-TR1. In contrast, HCV-TR1 displayed amino acid substitutions in 6 out of 9 major cytotoxic T-cell epitopes. These data suggest that HCV-TR1 encodes functionally intact viral proteins, but it also encodes altered viral epitopes, which may affect host immune-response.     

Determination of serum bile acids routinely may prevent delay in diagnosis of total parenteral nutrition-induced cholestasis

BACKGROUND/PURPOSE: Early diagnosis of development of cholestasis is a current major problem for patients receiving total parenteral nutrition (TPN). Conventional tests for hepatic function such as serum transaminases and alkaline phosphatase do not often reflect simultaneously histopathologic changes of the liver. The aim of this study is to find out the relationships between conventional hepatic function tests, total serum bile acid concentrations (TSBA), and the histopathologic changes in the liver during TPN administration in rats. METHODS: Forty Albino rats were divided into four experimental groups, each consisting of 10 rats, as follows: control group (C), 0.9% saline for 14 days; T7 group, TPN for 7 days; T14 group, TPN for 14 days; T7O7 group, TPN for 7 days and then 0.9% saline for the next 7 days. All solutions were administered by infusion through intraperitoneal catheter in two equal doses. During the experiment, rats also maintained on rat chow and water ad libitum. Levels of serum glutamic oxaloacetic transaminase, glutamic pyruvic transaminase, alkaline phosphatase, and TSBA were measured. Liver was evaluated histopathologically by light microscope and then Morphological Cholestasis Index (MCI) was calculated. RESULTS: Cholestasis was present in all experimental groups except control. Levels of transaminases and alkaline phosphatase were not correlated with the histopathologic changes (P > .05), but TSBA concentrations were correlated with MCI in all groups (P< .01). TSBA concentrations and MCI in all groups also were correlated with the duration of exposure with TPN (P< .01). CONCLUSIONS: Measurement of TSBA seems to be more sensitive in early diagnosis of TPN-induced cholestasis. Therefore, periodical determination of TSBA during TPN administration can be done routinely.     

Antiangiogenic treatment with endostatin inhibits progression of AML in vivo.

Increased vessel density in the bone marrow of patients with acute myeloid leukemia as well as elevated expression of proangiogenic factors by leukemic cells implies a central role of angiogenesis in hematological malignancies. Endostatin (ES), a fragment of collagen XVIII, is an endogenous inhibitor of angiogenesis that has shown therapeutic activity in solid tumors in various preclinical models. Using microencapsulation technology, we studied the therapeutic effect of ES in AML. While ES had no effect on proliferation of M1 murine leukemic cells in vitro, ES producing microbeads significantly inhibited growth of subcutaneous chloromas in SCID mice as compared to controls. In a leukemia model using M1 cells the concomitant treatment of mice with ES microbeads prolonged median survival significantly. Histological analysis revealed a decreased microvessel density and a reduced number of CD31-positive single cells, putatively endothelial progenitor cells, in the bone marrow of treated animals. Taken together, ES has inhibitory effects on neo-angiogenesis in the bone marrow and on progression of leukemia in vivo. These experiments suggest a possible therapeutic role of antiangiogenic gene therapy with ES in AML.     

Thalidomide has both anti-inflammatory and regulatory effects in Behcet's disease

Thalidomide is shown to be an effective treatment for mucocutaneous symptoms of Behcet's disease (BD). In this study, the effects of thalidomide on peripheral blood mononuclear cells were investigated ex vivo. In an open prospective study, ten patients were given 200 mg/day thalidomide for 12 weeks and cluster of differentiation 4 (CD4), CD8, CD11a, CD11b, CD16, CD18, CD28, CD44, CD45RO, CD45RA, CD56, CD120a and γδ+ T cells were analysed with flow cytometry at 0, 3, 7, 30 and 90 days. Two patients were excluded from the analysis for attacks of uveitis within the first 2 weeks. At day 7, tumour necrosis factor-α (TNF-α) receptor+ (CD120a; 12% vs 5%), CD8/CD11b+ (12% vs 6%) and CD16/CD56+ (16% vs 9%) cells decreased in BD patients compared to day 0. On the other hand, CD4+CD45RO+ T cells (24% vs 34%) at day 30 and γδ+ T cells (11% vs 21%) at day 90 increased after treatment. These results suggest that thalidomide tends to decrease TNF-α receptor levels, CD8/CD11b+ T cells and natural killer cells in early treatment and increases CD4+CD45RO+ memory T and γδ+ T cells later in BD.