Magnetic resonance elastography with guided pressure waves

Magnetic resonance elastography aims to non-invasively and remotely characterize the mechanical properties of living tissues. To quantitatively and regionally map the shear viscoelastic moduli in vivo, the technique must achieve proper mechanical excitation throughout the targeted tissues. Although it is straightforward, ante manibus, in close organs such as the liver or the breast, which practitioners clinically palpate already, it is somewhat fortunately highly challenging to trick the natural protective barriers of remote organs such as the brain. So far, mechanical waves have been induced in the latter by shaking the surrounding cranial bones. Here, the skull was circumvented by guiding pressure waves inside the subject's buccal cavity so mechanical waves could propagate from within through the brainstem up to the brain. Repeatable, reproducible and robust displacement fields were recorded in phantoms and in vivo by magnetic resonance elastography with guided pressure waves such that quantitative mechanical outcomes were extracted in the human brain.     

Phase I and pharmacokinetic study of gefitinib in children with refractory solid tumors: a Children's Oncology Group Study.

PURPOSE: Epidermal growth factor receptor is expressed in pediatric malignant solid tumors. We conducted a phase I trial of gefitinib, an epidermal growth factor receptor tyrosine kinase inhibitor, in children with refractory solid tumors. PATIENTS AND METHODS: Gefitinib (150, 300, 400, or 500 mg/m2) was administered orally to cohorts of three to six patients once daily continuously until disease progression or significant toxicity. Pharmacokinetic studies were performed during course one (day 1 through 28). RESULTS: Of the 25 enrolled patients, 19 (median age, 15 years) were fully evaluable for toxicity and received 54 courses. Dose-limiting toxicity was rash in two patients treated with 500 mg/m2 and elevated ALT and AST in one patient treated with 400 mg/m2. The maximum-tolerated dose was 400 mg/m2/d. The most frequent non-dose-limiting toxicities were grade 1 or 2 dry skin, anemia, diarrhea, nausea, and vomiting. One patient with Ewing's sarcoma had a partial response. Disease stabilized for 8 to > or = 60 weeks in two patients with Wilms' tumor and two with brainstem glioma (one exophytic). At 400 mg/m2, the median peak gefitinib plasma concentration was 2.2 microg/mL (range, 1.2 to 3.6 microg/mL) and occurred at a median of 2.3 hours (range, 2.0 to 8.3 hours) after drug administration. The median apparent clearance and median half-life were 14.8 L/h/m2 (range, 3.8 to 24.8 L/h/m2) and 11.7 hours (range, 5.6 to 22.8 hours), respectively. Gefitinib systemic exposures were comparable with those associated with antitumor activity in adults. CONCLUSION: Oral gefitinib is well tolerated in children. Development of the drug in combination with cytotoxic chemotherapy will be pursued.     

Signs of oral dryness in relation to salivary flow rate,pH, buffering capacity and dry mouth complaints

Background  

This study aimed to investigate the signs of oral dryness in relation to different salivary variables and to correlate subjective complaints of oral dryness with salivary flow rate.     

Malignant deciduoid mesothelioma: a diagnostic challenge

Malignant deciduoid mesothelioma, a rare phenotype of epithelioid mesothelioma, arises more commonly from the peritoneum of young women, but it is also reported in the pleura of elderly people. We report a case of malignant deciduoid mesothelioma that occurred in a 41-year-old woman after cesarean section and was initially misdiagnosed as pseudotumoral deciduosis. Microscopically, the tumor was entirely composed of deciduoid areas, and only scattered tumor cells were positive for calretinin and keratin 5/6. The patient died 14 months after the first operation. This observation confirms the poor prognosis of this entity and the importance of the differential diagnosis of pseudotumoral deciduosis.     

Bacteraemia post-autologous haematopoietic stem cell transplantation in the absence of antibacterial prophylaxis: a decade’s experience from Lebanon

Purpose

In this study, we assessed the incidence, contributing factors and outcome of prolonged neutropenia above 7 days and of bacteraemia in patients with lymphoma and multiple myeloma who underwent autologous haematopoietic stem cell transplantation (AHSCT) without antibacterial prophylaxis.

Methods

This is a retrospective chart review of 190 adult patients who underwent AHSCT between 2005 and 2015 at a Lebanese hospital.

Results

Neutropenia of 7 days duration and longer was documented in 66% of the patient population. Through univariate analysis, patients with lymphoma were significantly more likely to have prolonged neutropenia (≥?7 days) compared to those with myeloma. Mucositis above grade 3, diarrhoea and fever were more likely to occur in patients with prolonged neutropenia. Bacteraemia was documented in 12.6% of the patients. Total mortality rate was 3.7%, and that attributed to bacteraemia was 12.5% in the bacteraemia subgroup. Among bacterial isolates recovered from clinical specimens (89 isolates), 70% were Gram-negative, of which 57% were fluoroquinolone susceptible. Ninety-five percent of the Gram-negative bacteria causing bacteraemia were susceptible to fluoroquinolones.

Conclusion

Bacterial pathogens causing bacteraemia were still highly susceptible to fluoroquinolones, despite the high prevalence of fluoroquinolone-resistant strains in the general bacterial ecology. Accordingly, the pertinence of fluoroquinolone prophylaxis in the AHSCT setting warrants further investigation. Moreover, continuous surveillance of local antibiograms in this patient population has become a must in an era of preponderant antibiotic resistance.

     

Deep sequencing revealed genome-wide single-nucleotide polymorphism and plasmid content of Erwinia amylovora strains isolated in Middle Atlas,Morocco

Erwinia amylovora causes economic losses that affect pear and apple production in Morocco. Here, we report comparative genomics of four Moroccan E. amylovora strains with the European strain CFBP1430 and North-American strain ATCC49946. Analysis of single nucleotide polymorphisms (SNPs) revealed genetic homogeneity of Moroccan's strains and their proximity to the European strain CFBP1430. Moreover, the collected sequences allowed the assembly of a 65 kpb plasmid, which is highly similar to the plasmid pEI70 harbored by several European E. amylovora isolates. This plasmid was found in 33% of the 40 E. amylovora strains collected from several host plants in 2009 and 2010 in Morocco.     

Microleakage of Ormocer-based restorative material in primary teeth: an in vivo study

This in vivo study aimed to compare, by means of dye penetration, the microleakage values of an Ormocer-based material (Admira) and a commonly-used composite resin (Restorative Z-100) and to assess the differences in the degree of microleakage according to the cavity wall location for both tested materials. No statistically significant differences were found in the degree of microleakage between the 2 materials or the location of cavity walls. Additional preventive measures should be considered to minimize leakage since none of the restorative systems used, eliminated microleakage.