P. aeruginosa tRNA-fMet halves secreted in outer membrane vesicles suppress lung inflammation in cystic fibrosis

Although tobramycin increases lung function in people with cystic fibrosis (pwCF), the density of Pseudomonas aeruginosa (P. aeruginosa) in the lungs is only modestly reduced by tobramycin; hence, the mechanism whereby tobramycin improves lung function is not completely understood. Here, we demonstrate that tobramycin increases 5' tRNA-fMet halves in outer membrane vesicles (OMVs) secreted by laboratory and CF clinical isolates of P. aeruginosa. The 5' tRNA-fMet halves are transferred from OMVs into primary CF human bronchial epithelial cells (CF-HBEC), decreasing OMV-induced IL-8 and IP-10 secretion. In mouse lungs, increased expression of the 5' tRNA-fMet halves in OMVs attenuated KC (murine homolog of IL-8) secretion and neutrophil recruitment. Furthermore, there was less IL-8 and neutrophils in bronchoalveolar lavage fluid isolated from pwCF during the period of exposure to tobramycin versus the period off tobramycin. In conclusion, we have shown in mice and in vitro studies on CF-HBEC that tobramycin reduces inflammation by increasing 5' tRNA-fMet halves in OMVs that are delivered to CF-HBEC and reduce IL-8 and neutrophilic airway inflammation. This effect is predicted to improve lung function in pwCF receiving tobramycin for P. aeruginosa infection.NEW & NOTEWORTHY The experiments in this report identify a novel mechanism, whereby tobramycin reduces inflammation in two models of CF. Tobramycin increased the secretion of tRNA-fMet halves in OMVs secreted by P. aeruginosa, which reduced the OMV-LPS-induced inflammatory response in primary cultures of CF-HBEC and in mouse lung, an effect predicted to reduce lung damage in pwCF.

P. aeruginosa tRNA-fMet halves secreted in outer membrane vesicles suppress lung inflammation in Cystic Fibrosis

Although tobramycin increases lung function in people with cystic fibrosis (pwCF), the density of Pseudomonas aeruginosa (P. aeruginosa) in the lungs is only modestly reduced by tobramycin; hence, the mechanism whereby tobramycin improves lung function is not completely understood. Here, we demonstrate that tobramycin increases 5' tRNA-fMet halves in outer membrane vesicles (OMVs) secreted by laboratory and CF clinical isolates of P. aeruginosa . The 5' tRNA-fMet halves are transferred from OMVs into primary CF human bronchial epithelial cells (CF-HBEC), decreasing OMV-induced IL-8 and IP-10 secretion. In mouse lung, increased expression of the 5' tRNA-fMet halves in OMVs attenuated KC secretion and neutrophil recruitment. Furthermore, there was less IL-8 and neutrophils in bronchoalveolar lavage fluid isolated from pwCF during the period of exposure to tobramycin versus the period off tobramycin. In conclusion, we have shown in mice and in vitro studies on CF-HBEC that tobramycin reduces inflammation by increasing 5' tRNA-fMet halves in OMVs that are delivered to CF-HBEC and reduce IL-8 and neutrophilic airway inflammation. This effect is predicted to improve lung function in pwCF receiving tobramycin for P. aeruginosa infection.

New and noteworthy

The experiments in this report identify a novel mechanim whereby tobramycin reduces inflammation in two models of CF. Tobramycin increased the secretion of tRNA-fMet haves in OMVs secreted by P. aeruginiosa , which reduced the OMV-LPS induced inflammatory response in primary cultures of CF-HBEC and in mouse lung, an effect predicted to reduce lung damage in pwCF.

Graphical abstract

The anti-inflammatory effect of tobramycin mediated by 5' tRNA-fMet halves secreted in P. aeruginosa OMVs. (A) P. aeruginosa colonizes the CF lungs and secrets OMVs. OMVs diffuse through the mucus layer overlying bronchial epithelial cells and induce IL-8 secretion, which recruits neutrophils that causes lung damage. ( B ) Tobramycin increases 5' tRNA-fMet halves in OMVs secreted by P. aeruginosa . 5' tRNA-fMet halves are delivered into host cells after OMVs fuse with lipid rafts in CF-HBEC and down-regulate protein expression of MAPK10, IKBKG, and EP300, which suppresses IL-8 secretion and neutrophils in the lungs. A reduction in neutrophils in CF BALF is predicted to improve lung function and decrease lung damage.

Peri-operative management of obese patients in digestive surgery: Clinical practice guidelines from the French Society of Digestive Surgery

INTRODUCTION

The French Society of Digestive Surgery (Société Française de Chirurgie Digestive [SFCD]) has elaborated clinical practice guidelines for the management of the obese patient undergoing gastro-intestinal surgery.

METHODS

The literature was analyzed according to the GRADE® (Grading of Recommendations Assessment, Development and Evaluation) methodology divided into five chapters: preoperative management, modalities of transportation and installation of the patient in the operating room, specific characteristics related to laparoscopic surgery, specific characteristics related to traditional surgery, and postoperative management. Each question was formulated according to the PICO format (Patients, Intervention, Comparison, Outcome).

RESULTS

Synthesis of expert opinions and the application of the GRADE methodology produced 30 recommendations among which three were strong and nine were weak. The GRADE methodology could not be applied for 18 questions, for which only expert opinion was obtained.

CONCLUSION

These clinical practice guidelines can help surgeons optimize the peri-operative management of the obese patient undergoing gastro-intestinal surgery.

An rRNA fragment in extracellular vesicles secreted by human airway epithelial cells increases the fluoroquinolone sensitivity of P. aeruginosa

Lung infections caused by antibiotic resistant strains of Pseudomonas aeruginosa are difficult to eradicate in immunocompromised hosts such as those with cystic fibrosis. We previously demonstrated that extracellular vesicles (EVs) secreted by primary human airway epithelial cells (AEC) delivermiRNA let-7b-5p to P. aeruginosa to suppress biofilm formation and increase sensitivity to beta-lactam antibiotics. In this study, we show that EVs secreted by AEC transfer multiple distinct sRNA fragments to P. aeruginosa that are predicted to target the three subunits of the fluoroquinolone efflux pump MexHI-OpmD, thus increasing antibiotic sensitivity. Exposure of P. aeruginosa to EVs resulted in a significant reduction in the protein levels of MexH (-48%), MexI (-50%) and OpmD (-35%). Moreover, EVs reduced planktonic growth of P. aeruginosa in the presence of the fluoroquinolone antibiotic ciprofloxacin by 20%. A mexGHI-opmD deletion mutant of P. aeruginosa phenocopied this increased sensitivity to ciprofloxacin. Finally, we found that a fragment of an 18S rRNA external transcribed spacer that was transferred to P. aeruginosa by EVs reduced planktonic growth of P. aeruginosa in the presence of ciprofloxacin, reduced the minimum inhibitory concentration (MIC) of P. aeruginosa for ciprofloxacin by over 50%, and significantly reduced protein levels of both MexH and OpmD. In conclusion, an rRNA fragment secreted by AEC in EVs that targets the fluoroquinolone efflux pump MexHI-OpmD down-regulated these proteins and increased the ciprofloxacin sensitivity of P. aeruginosa. A combination of rRNA fragments and ciprofloxacin packaged in nanoparticles or EVs may benefit patients with antibiotic-resistant P. aeruginosa infections.

SARS-CoV-2 Testing and Patient Waiting Times in the Emergency Department

Aim Emergency Departments (EDs) were impacted early in the coronavirus disease 2019 (COVID-19) pandemic, with high attendance numbers. EDs relied upon SARS-CoV-2 reverse-transcriptase polymerase chain reaction (RT-PCR) tests to triage patients and facilitate admission to appropriate wards, meaning positive patients were isolated as early as possible. In October 2020, we introduced a 24-hour SARS-CoV-2 testing service. We examined the impact of this on patient experience times (PETs) in the ED, and on healthcare-associated (HA) COVID-19 infections. Methods Data on PETs before and after the introduction of 24-hour testing were available from the ED. HA COVID-19 infections were reported weekly to the Health Services Executive as a key performance indicator. Results Mean PET prior to the pandemic was 20 hours and dropped to 10 and 13 hours respectively in the first and second wave. A surge in case numbers and ED attendances during the third wave was not reflected in a rise in PETs, with a mean PET of 11 hours, significantly below pre-pandemic levels. HA-COVID-19 infections remained stable between wave one and three (83 v 92). Conclusion The introduction of 24-hour SARS-CoV-2 testing in our ED contributed to a reduction in PETs, facilitated appropriate patient placement at ward level, and kept HA-COVID-19 infections at acceptably low levels.

Comparison of intubating conditions after induction with propofol and remifentanil or sufentanil : Randomized controlled REMIDENT trial for surgical tooth extraction

PURPOSE

The aim of this study was to compare tracheal intubation conditions after induction of anesthesia with a bolus of propofol-sufentanil or propofol-remifentanil and a rapid induction technique.

MATERIAL AND METHODS

A total of 70 patients (American Society of Anesthesiologists (ASA) classification I‑II) undergoing outpatient surgery under general anesthesia with intubation for tooth extraction were randomly assigned to two groups in this double-blind study. Patients received either a bolus of remifentanil (3 μg/kg) or sufentanil (0.3 μg/kg) together with 2.5 mg/kg propofol for intubation. The primary outcome was the percentage of excellent intubation conditions and the secondary outcomes were the percentage of patients with a decrease of over 20% in mean arterial pressure (MAP) or heart rate (HR), time to achieve spontaneous respiration, time between the end of surgery and extubation and time to achieve an Aldrete score of 10. VAS pain score was >3 or having laryngeal pain 15 min after arriving in the postanesthesia care unit (PACU) were also analyzed.

RESULTS

Intubating conditions (perfect + good conditions) were significantly better with remifentanil than with sufentanil (88.5% vs. 68.6%; p = 0.01). When using remifentanil, the hemodynamic conditions were good. Using remifentanil did not significantly increase the pain score or the laryngeal pain in the recovery room. This was confirmed by no significant differences between the groups for morphine consumption. Remifentanil significantly decreased the time to achieve an Aldrete score of 10.

CONCLUSION

When intubation without muscle relaxants is required, intubating conditions are much better when a remifentanil bolus is used compared to a sufentanil bolus. The remifentanil/propofol rapid induction technique is a valuable technique to quickly intubate and achieve good conditions.

OS8.7 Targeting Pi3k-Akt-mTOR and MAPKinase pathways in aggressive meningiomas: in vitro study

BACKGROUND

Recurrent and aggressive meningiomas remain an unmet medical need in neuro-oncology. In our preclinical model on meningioma primary cell culture, the combination of the mTOR inhibitor, everolimus and the somatostatin analog, octreotide decreased cell viability and proliferation without inducing apoptosis. The interest of the combined treatment everolimus plus octreotide were clinically validated by the CEVOREM clinical trial demonstrating a decrease in growth rate of meningiomas in most treated patients.

Nevertheless, everolimus induced an increase in Akt activity in vitro, which probably limited everolimus efficiency. We hypothesized that targeting Pi3K could prevent this positive feedback on Akt phosphorylation, induced by mTOR inhibition. The involvement of MAPKinase pathway in meningioma tumorigenesis was recently demonstrated. Our aim was to decipher the effect of the Pi3k α inhibitor Alpelisib (BYL719) and the specific inhibitor of MEK1,2 Mekinist (Trametinib) alone or in combination, in comparison to the mTor inhibitor everolimus on human meningioma primary cell cultures.

MATERIAL AND METHODS

The impact of the drugs was studied on 40 meningiomas, well characterized at clinical, histological and molecular level. The cell viability, cell proliferation and apoptosis were analyzed under drugs.

RESULTS

BYL719 induced a dose dependent decrease in cell viability (maximal effect -90%, IC50 10-6M) in all tested meningiomas (n=30). This effect was stronger than those of everolimus (maximal effect -50%, n=24, IC50 10-8M). 22 tumors were sensitive to Trametinib (maximal effect <-50%, IC50 10–5 M), 14 were partially sensitive (maximal effect between -20 and -40% IC50 10–5 M) and 3 were resistant. An apoptotic effect was observed under BYL719 in 6/18 tested tumors whereas no apoptosis was observed under Trametinib and Everolimus. Combination of BYL719 and Trametinib induced a significant stronger decrease in cell viability than each drug alone. Correlation analysis between these functional results, the tumor genomic profile and the activation of ERK/MEK kinase pathway is ongoing.

CONCLUSION

PI3K-Akt-mTOR and ERK/MEK kinase pathways constitute relevant targets in aggressive meningioma therapy. In our preclinical model, previously validated by CEVOREM clinical trial, co-targeting Pi3k-Akt-mTOR and MAPkinase pathways improved cell proliferation inhibition in comparison to the target of each pathway alone. BYL719 induced apoptosis which was not achieved by everolimus. These results support the ongoing clinical trial ALTREM combining Alpelisib and Trametinib on patients harboring aggressive recurrent meningiomas.

Transvaginal ultrasound-guided embryo transfer in IVF

OBJECTIVES

To determine whether transvaginal ultrasound-guided embryo transfer is a technique that can be used routinely, whether it improves IVF outcomes and whether it makes difficult transfers easier and more successful.

MATERIAL AND METHOD

Non-randomized retrospective study conducted between 2012 and 2016 in the fertility center of the Diaconesses-Croix St-Simon hospital group. The outcomes of 3910 transfers, performed by 5 senior operators, under transabdominal ultrasound guidance are compared with those of 800 transfers, performed by 1 senior operator under transvaginal ultrasound guidance. The criteria studied are the feasibility of the technique and the percentage of pregnancies per transfer in the two populations described, as well as in the difficult and very difficult transfer populations.

RESULTS

All the transfers were feasible under transvaginal ultrasound guidance without the use of forceps or additional instruments. The percentage of pregnancies per transfer is significantly increased, when the transfer is performed under transvaginal ultrasound guidance compared with that performed under transabdominal ultrasound guidance, in the general population (38%, n=800 vs 30%, n=3910; P 0.0004) and in the reference population characterized by age <38 years and >6 oocytes collected per puncture (45%, n=490 vs 36%, n=1968; P 0.002). The percentage of pregnancies per transfer (P/T) is not significantly different in the populations of easy transfers (n 695, 38% P/T), difficult transfers (n 58, 46% P/T; P=ns) and very difficult transfers (n 47, 34% P/T; P=ns).

CONCLUSIONS

Embryo transfer is a key stage in IVF, in which the quality of performance determines the outcome. In this study, transvaginal ultrasound guidance of the transfer, which is the reference procedure in gynaecological imaging, significantly increases the percentage of pregnancies per transfer, both in the general population and in the reference population, compared with transfers performed under transabdominal ultrasound guidance. Transvaginal ultrasound facilitates the performance of difficult transfers and in particular achieves outcomes in these situations that are not significantly different from those of easy transfers. Visual monitoring of transcervical passage, which is rendered more precise and less traumatic and precision of embryo deposition are the factors that probably account for the improvement in outcomes.

[What's new in 2014 about anti-Müllerian hormone?]

The existence of the anti-Müllerian hormone (AMH) has been postulated by Professor Alfred Jost to explain the regression of the Müllerian ducts during male sexual differentiation. Since then, AMH has been purified, its gene and specific receptor, AMHR-II have been cloned. Further, the signaling pathways were identified and it has been observed that AMH was produced by the granulosa cells of growing follicles. From the 2000s, unexpected roles of AMH have been highlighted, reactivating international research on this hormone. It is now well established that AMH plays a key role in the follicular recruitment and development. Over the past years, serum AMH measurements have been proposed as a marker of the follicular ovarian status, and a predictor of assisted reproductive cycles. AMH is also useful to assess the effectiveness of treatment of some gynecological tumors. This article is a review of the past five years advances on the regulation of the expression of AMH and its specific receptor AMHR-II in female.

[48,XXYY men with azoospermia: how to manage infertility?]

48,XXYY syndrome is a rare form of sex chromosomal aneuploidy. Usually considered as a variant of Klinefelter syndrome because of shared features (azoospermia, tall stature, hypergonadotropic hypogonadism), it is a separate entity because diagnostic is currently made in prepubertal boy with neuro-psychological disorders. We here report the case of a 48,XXYY patient consulting for adult infertility and the indication to perform testicular sperm extraction is discussed.

[Assessment of malaria screening management in blood donation control in the French Military Blood Institute]

The French Military Blood Institute is responsible for the entire blood supply chain in the French Armed Forces. Considering, the high exposition rate of military to malaria risk, blood donation screening of plasmodium infection must be as efficient as possible. The main aim of our study was to assess our malaria testing strategy based on a single Elisa test compared with a two-step strategy implying immunofluorescence testing as confirmation test. The second goal was to describe characteristic of malaria Elisa positive donors. We conducted a prospective study: every malaria Elisa positive test was implemented by immunofluorescence testing and demographical data were recorded as usual by our medical software. We showed a significant risk of malaria ELISA positive tests among donor born in endemic area and we estimate the number of abusively 3-year rejected donors. However, based on our estimations, the two-step strategy is not relevant since the number of additionally collected blood products will be low.

Potential for Zika virus transmission through blood transfusion demonstrated during an outbreak in French Polynesia, November 2013 to February 2014

Since October 2013, French Polynesia has experienced the largest documented outbreak of Zika virus (ZIKAV) infection. To prevent transmission of ZIKAV by blood transfusion, specific nucleic acid testing of blood donors was implemented. From November 2013 to February 2014: 42 (3%) of 1,505 blood donors, although asymptomatic at the time of blood donation, were found positive for ZIKAV by PCR. Our results serve to alert blood safety authorities about the risk of post-transfusion Zika fever.

Investigation of the first outbreak of OXA-48-producing Klebsiella pneumoniae in Ireland

BACKGROUND

Carbapenemase-producing Enterobacteriaceae (CPE) strains are encountered with increasing frequency in Europe. In November 2010 the European Centre for Disease Control (ECDC) graded Ireland as only having sporadic occurrence of CPE.

AIM

To describe the epidemiological and molecular typing analysis of the first outbreak of OXA-48-producing Klebsiella pneumoniae in an Irish tertiary care referral centre.

METHODS

Sixteen OXA-48-producing K. pneumoniae isolates were detected, from both clinical and screening specimens, and analysed by pulsed-field gel electrophoresis and by multi-locus sequence typing.

FINDINGS

Typing analysis revealed that two outbreak strains were circulating in the hospital, one among surgical patients and one among medical patients. The 'medical strain' ST13 had already been identified as an internationally disseminated clone, whereas the 'surgical strain' ST221 had not previously been reported as an OXA-48-carrying strain.

CONCLUSION

Although the outbreak on surgical wards was successfully controlled by implementing strict infection control measures, intermittent detection of individual patients carrying the 'medical strain' of OXA-48 K. pneumoniae has persisted since then. The experience from this outbreak suggests that OXA-48 K. pneumoniae is endemic at low level in the healthcare setting in the Dublin region.

Altered MENIN expression disrupts the MAFA differentiation pathway in insulinoma

The protein MENIN is the product of the multiple endocrine neoplasia type I (MEN1) gene. Altered MENIN expression is one of the few events that are clearly associated with foregut neuroendocrine tumours (NETs), classical oncogenes or tumour suppressors being not involved. One of the current challenges is to understand how alteration of MENIN expression contributes to the development of these tumours. We hypothesised that MENIN might regulate factors maintaining endocrine-differentiated functions. We chose the insulinoma model, a paradigmatic example of well-differentiated pancreatic NETs, to study whether MENIN interferes with the expression of v-MAF musculoaponeurotic fibrosarcoma oncogene homologue A (MAFA), a master glucose-dependent transcription factor in differentiated β-cells. Immunohistochemical analysis of a series of human insulinomas revealed a correlated decrease in both MENIN and MAFA. Decreased MAFA expression resulting from targeted Men1 ablation was also consistently observed in mouse insulinomas. In vitro analyses using insulinoma cell lines showed that MENIN regulated MAFA protein and mRNA levels, and bound to Mafa promoter sequences. MENIN knockdown concomitantly decreased mRNA expression of both Mafa and β-cell differentiation markers (Ins1/2, Gck, Slc2a2 and Pdx1) and, in parallel, increased the proliferation rate of tumours as measured by bromodeoxyuridine incorporation. Interestingly, MAFA knockdown alone also increased proliferation rate but did not affect the expression of candidate proliferation genes regulated by MENIN. Finally, MENIN variants with missense mutations detected in patients with MEN1 lost the WT MENIN properties to regulate MAFA. Together, our findings unveil a previously unsuspected MENIN/MAFA connection regarding control of the β-cell differentiation/proliferation balance, which could contribute to tumorigenesis.

First isolation and outbreak of OXA-48-producing Klebsiella pneumoniae in an Irish hospital, March to June 2011

Five OXA-48-producing Klebsiella pneumoniae were detected in a tertiary referral hospital in Ireland between March and June 2011. They were found in the clinical isolates of five cases that were inpatients on general surgical wards. None of the cases had received healthcare at a facility outside of Ireland in the previous 12 months. This is the first report of OXA-48-producing K. pneumoniae in Ireland.

First isolation and outbreak of OXA-48-producing Klebsiella pneumoniae in an Irish hospital, March to June 2011

Five OXA-48-producing Klebsiella pneumoniae were detected in a tertiary referral hospital in Ireland between March and June 2011. They were found in the clinical isolates of five cases that were inpatients on general surgical wards. None of the cases had received healthcare at a facility outside of Ireland in the previous 12 months. This is the first report of OXA-48-producing K. pneumoniae in Ireland.

[Hemoglobinopathy. Laboratory diagnosis]

Hemoglobinopathies are the most common genetic diseases in the world. They are most frequent in areas where malaria is endemic. Sickle cell disease and severe thalassemia require prompt diagnosis. The purpose of this article is to describe first-line techniques for diagnosis in non-specialized laboratories with special emphasis on the pitfalls of interpreting results.

Chevrel Phases as Good Thermoelectric Materials

Chevrel phases have an open lattice with large voids in which cations can be inserted. These cations are good scattering centers for phonons. The thermal conductivity of these compounds must be low. Chevrel phases are generally metallic, but we calculated the density of states of several compounds and we found that Zn2Mo6Se8, Cd2Mo6Se8, TiMo6Se8 are semiconducting whereas SnMo6Se8, Cu2Mo6Se8 and CrMo6Se8 are metallic. We are currently trying to synthesize Zn2Mo6Se8 by different ways.

A travel misadventure--visceral leishmaniasis in an immunocompetent patient

Visceral leishmaniasis is one of the world's most neglected diseases. Over 90% of the 500,000 annual new cases occur in only five countries: India, Nepal, Bangladesh, Sudan and North-Eastern Brazil, but the disease remains endemic in Southern Europe. We report a case of visceral leishmaniasis in an immunocompetent serviceman after a seven-day stay in the Marseilles region of South-Eastern France. This case is intended to alert clinicians to the possibility of visceral leishmaniasis in patients who develop a febrile illness after returning from travel in Southern European countries.

Homology of complete genome sequences for dengue virus type-1, from dengue-fever- and dengue-haemorrhagic-fever-associated epidemics in Hawaii and French Polynesia

Dengue epidemic virulence is thought to be conferred by various factors, including the genotype of the virus involved. Increased or decreased epidemic virulence has been associated not only with the introduction of type-2 (DENV-2) strains into the South Pacific, the Caribbean and South America, but also with newly emergent DENV-3 genotypes in Sri Lanka, and the year-to-year variation in the DENV-4 strains circulating in Puerto Rico. These observations indicate that there are inherent differences among viral genotypes in their capacity to induce severe disease, that is, their virulence potential. The present study involved a comparison of the complete genome sequences of DENV-1 viruses that had been isolated from cases of dengue fever (DF) or dengue haemorrhagic fever (DHF) that occurred in French Polynesia or Hawaii in 2001, when a virulent DHF-associated dengue epidemic was occurring throughout the Pacific region. Previous studies have identified putative virulence-associated motifs and substitutions in the DENV-2 genome, and the main aim of the present study was to identify similar changes in DENV-1 that may be associated with viral virulence. As no virulence determinants were seen, however, in any gene or untranslated region, it appears that genotype is not the sole determinant of virulence in DENV-1. Further studies, to compare DF- and DHF-associated strains of DENV-1 isolated from epidemics of variable virulence, in the same eco-biological context, are needed.

MR enterography in the evaluation of small bowel dilation

Magnetic reasonance (MR) enterography enables high contrast resolution depiction of the location and cause of bowel obstruction through a combination of predictable luminal distension and multiplanar imaging capabilities. Furthermore, because the patient is not exposed to ionizing radiation, sequential "dynamic" MR imaging can be performed repeatedly over time further facilitating depiction of the site and/or the cause of obstruction. With increasing availability of MR imaging and standardization of the oral contrast medium regimens, it is likely that this technique will assume an ever-increasing role in the evaluation of small bowel dilation in the coming years. We illustrate the utility of MR enterography in the evaluation of small bowel dilation, whether it be mechanical, functional (e.g., ileus), or related to infiltrative mural disease.

Predicting risk of developing invasive breast cancer in the African American female population

11080

Background: African Americans (AA) have a lower incidence of breast cancer with a poorer prognosis than Caucasians. It is unclear whether AA women have fewer known risk factors for breast cancer or that risk factors have a lesser effect in AA. We evaluated the accuracy of the race-based modification Gail Model in predicting the risk of developing invasive breast cancer in the AA population. Methods: With IRB approval, we performed a retrospective analysis of data obtained from women (n=15,973) ages 40–79 presenting to our Breast Center(5/2003 to 7/2005) for a screening mammogram. The five-year probability of breast cancer for AA (n=702) versus Caucasians (n=15,721) was calculated for each individual using 3 methods: 1) the race specific Gail model, 2) the Gail model ignoring race (AA using the Caucasian model), and 3) age and race matched SEER projection using DevCan (v6.1.1) software. Results: There was no significant difference between the 5-year probability of breast cancer for Caucasians as calculated by the Gail model vs. the SEER prediction (p=NS), suggesting our population was representative of the larger study population from which SEER data was derived. As compared to SEER prediction, the modified Gail model underestimated the breast cancer risk for all age groups of AA (p<0.0001). When the Gail Model without the race-based modification was applied to the AA population, the projected risk was not significantly different from the SEER prediction (p=0.1049). Conclusions: This study suggests that the race-based modification of the Gail Model underestimate the risk of breast cancer in AA women. When the model is applied to AA women without incorporating the modification for race, the Gail model accurately reflects SEER 5-year projections of risk of invasive cancer in AA women. Differences in risk factor distribution among race, rather than a differential effect of those factors on risk, may have a substantial role in explaining the lower incidence in AA women as compared to Caucasian women over 40.

[Table: see text]

No significant financial relationships to disclose.

First identification of class A carbapenemase-producing Klebsiella pneumoniae in the Republic of Ireland

The Klebsiella pneumoniae carbapenemase (KPC) was detected in a carbapenem-resistant respiratory isolate of Klebsiella pneumoniae in an Irish hospital. This is the first report of a KPC-producing isolate in the Republic of Ireland. The isolate was resistant to all beta-lactams. Furthermore, it had reduced susceptibility to three other classes of non-beta-lactam antibiotics. The isolate was not associated with travel abroad. Detection of KPC-producing bacteria has important infection control and public health implications.

First identification of class A carbapenemase-producing Klebsiella pneumoniae in the Republic of Ireland

The Klebsiella pneumoniae carbapenemase (KPC) was detected in a carbapenem-resistant respiratory isolate of Klebsiella pneumoniae in an Irish hospital. This is the first report of a KPC-producing isolate in the Republic of Ireland. The isolate was resistant to all β-lactams. Furthermore, it had reduced susceptibility to three other classes of non-β-lactam antibiotics. The isolate was not associated with travel abroad. Detection of KPC-producing bacteria has important infection control and public health implications.

CT evaluation of Chamberlain's, McGregor's, and McRae's skull-base lines

AIM

To evaluate the mean distance from the odontoid process of C2 to the standard skull-base lines (Chamberlain's, McGregor's, and McRae's lines) on computed tomography (CT) imaging. To compare these measurements to previously documented plain radiograph and magnetic resonance imaging (MRI) measurements.

MATERIALS AND METHODS

Reformatted midline sagittal CT images of 150 adults were retrospectively evaluated. The shortest perpendicular distance was measured from the Chamberlain's, McGregor's and McRae's baselines for each subject to the odontoid tip. Statistical analysis was performed to compare the CT data with the previously obtained MRI and plain film data.

RESULTS

The mean position of the odontoid process was 1.4mm below Chamberlain's line (median 1.2 mm, SD 2.4 mm), 0.8 mm (median 0.9 mm, SD 3 mm) below McGregor's line and 5 mm (median 5 mm, SD 1.8 mm) below McRae's line. There is no significant difference between male and female results (p>0.05) or between these CT and previous MRI measurements (p>0.05).

CONCLUSION

These results provide the mean and range of normal distance from the odontoid process to the most frequently used skull-base lines on the current population on CT.

Characterization of neuro-endocrine tumors in an athymic nude mouse model using dedicated synchronization strategies for T2-weigted MR imaging at 7T

Endocrine tumours, with digestive localization, are tumours with variable forecast which are independent of their invasive and metastatic extensions. The experimental model of endocrine tumors with liver dissemination is available for evaluation of new medical therapeutics such as antiangiogenic therapy. MRI is a non invasive modality allowing in vivo examinations and is suitable to follow liver lesion evolution during longitudinal study on animal models. The goal of this study was to assess the detection level and to characterize the liver lesions in an athymic nude mouse model, using a dedicated MRI protocol and an optimized synchronization strategy at high magnetic field strength. The experiments were performed at 7T. To detect liver lesions, respiratory-triggered T2-weighted MR images is the sequence of choice. With conventional acquisition strategies used on small animal MR systems, trigger signal is performed at each respiratory cycle and thus, the T2 contrast is not freely controlled. Additionally, the slice number is limited by the expiration delay. To overcome these drawbacks, we proposed an original strategy enabling true T2-weighted imaging with minimal movement artifacts, regardless of the respiratory period and the number of slices. This protocol was used to carry out a longitudinal follow-up of hepatic lesions in 8 nude mice at stages D7, D12, D17 and D24. The fraction of lesion over the total liver volume was quantified. Moreover, the characterization of cystic or non-cystic type of lesions was achieved using various TE leading to T2 maps. In conclusion, the level of lesion detection and characterization of liver lesions was performed using a devoted protocol with original synchronization strategy dedicated to high field MRI. MR imaging could be used with relevance in the evaluation of new therapeutics protocol for treatment of liver lesions in neuroendocrine tumors using small animal model.

In-vivo high-resolution X-ray microtomography for liver and spleen tumor assessment in mice

The present study sought to validate the use of glycery1-2-oley-1,3-bis-[7-(3-amino-2,4,6-triiodophenyl)- heptanoate] (DHOG) contrast agent for mouse spleen tumor and liver metastasis imaging by high-resolution X-ray microtomography. Three groups of female nude mice were compared: controls (n = 5), and mice injected with 2.5 x 10(6) STC1 tumor cells in the spleen, imaged at 15 days (group G15, n = 5) and at 30 days (group G30, n = 5, of which one died before imaging). Micro-CT scans (X-ray voltage, 50 kVp; anode current, 200 microA; exposure time, 632 ms; 180 rotational steps resulting in 35 microm isotropic spatial resolution) were acquired at 0, 0.75, 2 and 4 h after i.v. injection of DHOG. CT number (Hounsfield units: HU) and contrast-to-noise ratios (CNR) were determined in three organs. Statistical analysis was performed by Mann-Whitney U-test. Contrast enhancement in normal spleen and liver increased, respectively to 1020 +/- 159 and 351 +/- 27 HU over baseline at 4 h, and 482 +/- 3 and 203 +/- 14 HU on day 6 after a single contrast injection. Automated three-dimensional reconstruction and modeling of the spleen provided accurate and quantifiable images. Spleen tumor and liver metastases did not take up DHOG, making them detectable in contrast to the increased signal in normal tissue. The smallest liver metastasis detected measured 0.3 mm in diameter. High-resolution X-ray micro-CT in living mice using DHOG contrast agent allowed visualization and volume quantification of normal spleen and of spleen tumor and its liver metastases.

MRI evaluation and measurement of the normal odontoid peg position

AIM

To measure the normal distances (and range) from the tip of the odontoid peg to the different reference skull baselines (Chamberlain's, McGregor's, and McRae's line) using magnetic resonance imaging (MRI).

MATERIALS AND METHODS

We retrospectively evaluated midline sagittal MRI brain images of 200 adults chosen randomly. Patients did not have symptoms or signs suggestive of basilar impression, spinal trauma, vertebral collapse or disease. Using SPSS data analysis program histograms, mean and standard deviation (SD), median and range values were calculated. These findings were then compared with previous plain radiograph measurements.

RESULTS

The mean position of the odontoid peg was 1.2 mm (median 1.5 mm, SD 3 mm) below Chamberlain's line; 0.9 mm (median 1.1, SD 3 mm) below McGregor's line; and 4.6 mm (median 4.8, SD 2.6) below McRae's line.

CONCLUSION

Based on the current population, these results provide the mean and range of normal distances from the odontoid peg to the most frequently used skull baselines using MRI.

LCIS and tamoxifen use: A single institution review

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Background: Results of the NSABP-P1 trial were published in 1998 showing a 50% reduction in breast cancer in the high- risk population with the use of tamoxifen. The use of tamoxifen is individualized, and depends on both patient and physician factors. We looked at the recommendations for and the use of tamoxifen in women with LCIS. Methods: A retrospective chart review at a single institution was performed from March 27, 1980 through September 19, 2005 for patients diagnosed with LCIS. Pathology and operative reports, as well as patient notes were reviewed for discussions about tamoxifen. Data was collected on whether a discussion took place, whether tamoxifen was or was not advised, whether the patient declined to take tamoxifen, whether they took it in the past or were currently on tamoxifen. We also examined the rate of DCIS and invasive cancer in this population. Results: There were 321 patients diagnosed with LCIS. Of those patients 193 were diagnosed after the publication of the P1 trial. Of these 193 patients we identified 104(54%) patients whose charts contained notes indicating a discussion about tamoxifen. The results of the discussion about tamoxifen are as follows: 21(20%) patients were currently taking tamoxifen, 16(15%) had taken it in the past, 37(36%) patients declined to take tamoxifen, and 17(16%) had not made a decision about taking tamoxifen. There were 13(13%) patients for whom tamoxifen was advised against. In the entire cohort of 321 patients, 15% went on to develop DCIS or invasive cancer in the first 12 years of follow up. We did not look at cancer rate Vs tamoxifen use due to the small numbers with available information. Conclusions: While the P1 trial recommends tamoxifen for breast cancer prevention in high-risk patients, in our experience, almost half of the patients did not have a documented discussion about the medication, and the majority of those who did decided not to take tamoxifen. This will likely have a large impact on the rate of DCIS and invasive breast cancer in this group.

No significant financial relationships to disclose.

When a stroke is not a stroke; posterior leukoencephalopathy syndrome mimicking posterior circulation stroke

Posterior leukoencephalopathy syndrome (PLS) is a potentially reversible syndrome that may mimic the clinical and radiological features of posterior circulation cerebral infarction. Three cases of PLS are presented which were erroneously diagnosed as strokes and treated in accordance with recent evidence based guidelines; none of the cases fulfilled the current criteria requiring treatment for hypertension in the acute stroke setting. Once the diagnosis of PLS was made, and the patients blood pressure treated aggressively, all patients had rapid and full clinical resolution of their symptoms. Given the important differences in management and prognosis, rapid and accurate diagnosis is essential. Posterior leukoencephalopathy syndrome needs to be considered in patients presenting with clinical and/or radiological findings that predominantly affect the occipital lobes.

Effectiveness of interferon plus ribavirin combination in the treatment of naive patients with hepatitis C virus type 5. A French multicentre retrospective study

AIM

To assess the rate of sustained virological response in naïve hepatitis C virus-type 5 patients treated by standard interferon or pegylated-interferon [corrected] (peg-interferon) and ribavirin combination for 48 weeks.

PATIENTS AND METHODS

A total of 87 hepatitis C virus patients were included from 12 centres in France; 28 patients received interferon plus ribavirin and 59 were treated with peg-interferon plus ribavirin.

RESULTS

Baseline characteristics were: mean age 58 +/- 11 years, sex ratio 1, 66% had metavir fibrosis score >or=F2, 21% were cirrhotics and 53% had pretherapeutic viral load >or=800,000 IU/mL. Sustained virological response was achieved in 64% and 58% of hepatitis C virus-5 patients treated with interferon and peg-interferon, respectively (NS). In adherent patients, sustained virological response was obtained in 75% of patients. Sustained virological response in hepatitis C virus-5 patients (60%) was significantly higher than sustained virological response in hepatitis C virus-1 patients (37%) (P = 0.0499) and not significantly different from sustained virological response in hepatitis C virus-2-3 patients (63%) (P = 0.8098).

CONCLUSIONS

Combination therapy is effective in 60% of hepatitis C virus-5-infected patients. Sustained virological response seems better in hepatitis C virus-5 patients than in hepatitis C virus-1 patients, and is similar to that of hepatitis C virus-2-3 patients. More studies are needed to determine optimal duration of treatment in hepatitis C virus-5 patients.