Engineering N-linked protein glycosylation with diverse O antigen lipopolysaccharide structures in Escherichia coli

Campylobacter jejuni has a general N-linked protein glycosylation system that can be functionally transferred to Escherichia coli. In this study, we engineered E. coli cells in a way that two different pathways, protein N-glycosylation and lipopolysaccharide (LPS) biosynthesis, converge at the step in which PglB, the key enzyme of the C. jejuni N-glycosylation system, transfers O polysaccharide from a lipid carrier (undecaprenyl pyrophosphate) to an acceptor protein. PglB was the only protein of the bacterial N-glycosylation machinery both necessary and sufficient for the transfer. The relaxed specificity of the PglB oligosaccharyltransferase toward the glycan structure was exploited to create novel N-glycan structures containing two distinct E. coli or Pseudomonas aeruginosa O antigens. PglB-mediated transfer of polysaccharides might be valuable for in vivo production of O polysaccharides-protein conjugates for use as antibacterial vaccines.     

The impact of intra operative ultrasound in metastases liver surgery

BACKGROUND: Twenty-five to 50% of the patients with hepatic metastases are potential candidates for curative surgery. Intraoperative ultrasound has been employed to guide the surgery. AIM: To evaluate this method in liver surgeries and compare it to other imaging methods. PATIENTS AND METHODS: Thirty-five patients (20 females, with median age of 56 years) with hepatic metastases were prospectively studied between February 2001 and July 2003. Patients had as primary tumors: colorectal cancer (24), neuroendocrine tumors (3), renal cell carcinoma (2), melanoma (2), others (4). Each patient was submitted to at least: computed tomography (30), ultrasonography (14) and magnetic resonance imaging (8). Intraoperative ultrasound was performed in all patients in order to detect liver nodules. The number and location of liver lesions were compared to preoperative results. RESULTS: Intraoperative ultrasound was useful in 23 (65.6%) of the 35 surgeries and changed the planned surgical strategy in 9 (25.7%). There was a statistical significant correlation between the mean number of nodules identified by ultrasonography, computed tomography, magnetic resonance imaging and intraoperative ultrasound. We found no statistical difference between magnetic resonance imaging and intraoperative ultrasound in identifying hepatic nodules. Fifty-five nodules were submitted to histological evaluation, the gold standard method and 52/55 (94.5%) were identified by intraoperative ultrasound. Intraoperative ultrasound identified 91.6% of the smaller than 1.5 cm lesions, ultrasonography identified 15.0% of them, computed tomography 33.3% and magnetic resonance imaging 66.6%. CONCLUSIONS: Intraoperative ultrasound is crucial in the evaluation and decision making in hepatic surgery. Intraoperative ultrasound presents the highest sensibility in the detection of hepatic nodules compared to other imaging methods, especially for small lesions.     

Diagnosis and management of hepatic artery in-stent restenosis after liver transplantation by optical coherence tomography:A case report

BACKGROUND Percutaneous transluminal angioplasty and stenting represent an effective treatment for hepatic artery stenosis after liver transplantation. In the first year after stenting, approximately 22% of patients experience in-stent restenosis, increasing the risk of artery thrombosis and related complications, and 50% experience liver failure. Although angiography is an important tool for diagnosis and the planning of therapeutic interventions, it may raise doubts, especially in small-diameter arteries, and it provides low resolution rates compared with newer intravascular imaging methods, such as optical coherence tomography(OCT).CASE SUMMARY A 64-year-old male developed hepatic artery stenosis one year after orthotropic liver transplantation and was successfully treated with percutaneous transluminal angioplasty with stenting. Five months later, the Doppler ultrasound results indicated restenosis. Visceral arteriography confirmed hepatic artery tortuosity but was doubtful for significant in-stent restenosis(ISR) and intrahepatic flow reduction. To confirm ISR, identify the etiology and guide treatment, OCT was performed. OCT showed severe stenosis due to four mechanisms: Focal and partial stent fracture, late stent malapposition, in-stent neointimal hyperplasia, and neoatherosclerosis.CONCLUSION Intravascular diagnostic methods can be useful in evaluating cases in which initial angiography results are not sufficient to provide a proper diagnosis of significant stenosis, especially with regard to ISR. A wide range of diagnoses are provided by OCT, resulting in different treatment options. Interventional radiologists should consider intravascular diagnostic methods as additional tools for evaluating patients when visceral angiography results are unclear.     

Specialized pro‐resolving lipid mediators in experimental periodontitis: A systematic review

Recently, several studies demonstrated the potential of using specialized pro‐resolving lipid mediators (SPMs), as a novel approach, in treating periodontitis in pre‐clinical models. This review aimed to systematically evaluate the biological actions of SPMs on periodontal tissues in animals with experimentally induced periodontitis. This systematic review was performed by following the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA) guidelines. Studies were searched in three databases. Meta‐analysis was not performed because of the data heterogeneity. Study quality was assessed using Systematic Review Centre for Laboratory Animal Experimentation (SYRCLE) Risk of Bias tool. Six studies using an experimental periodontitis model to test the efficacy of SPMs were selected. Resolvin E1 and lipoxins were topically applied to treat experimental periodontitis. Alveolar bone loss could be significantly prevented and regenerated by applying SPMs, when compared to the control group. The dosages of SPMs and the periods of disease induction varied based on the pre‐clinical model employed. Two studies further demonstrated the positive shift in microbial composition, in line with positive shift in inflammatory status, that are regulated by SPMs. Clinical studies are needed to optimize the application of SPMs in treating periodontal diseases in humans.     

The psychological impact of cryptic chromosomal abnormalities diagnosis announcement

This qualitative study aims to describe the psychological impact of the diagnosis announcement of pathogenic Copy Number Variations (pCNVs). We performed semi-structured interviews of 60 parents of 41 affected children and 5 geneticists who announced the diagnoses. The diagnosis of the best characterized microdeletion syndromes, often defined by patronymic names (e.g. Williams syndrome), is generally made on a clinical basis by geneticists and confirmed by fluorescence in situ hybridization analysis. Chromosomal microarray, on the contrary, can allow the disclosure of rare pCNVs named after cytogenetic formulas, with poorly known clinical consequences: this makes doctors feel less confident with these diagnosis announcements. The disclosure of pCNVs named after cytogenetic formulas does not facilitate the parental mental representation of the disease, leading some parents to call into question the genotype-phenotype correlation or the very notion of a diagnosis. The announcement of inherited pCNVs can increase the feeling of parental guilt; the disclosure of de novo pCNVs can induce a feeling of “breakage” in the mental representation of the parent-child vertical transmission. In conclusion, our study shows that the disclosure of pCNVs has a significant psychological impact: a multidisciplinary approach to the diagnosis announcement, including a psychological support, should be systematically warranted.