Effect of magnetic field and iron content on NMR proton relaxation of liver,spleen and brain tissues

Iron accumulation is observed in liver and spleen during hemochromatosis and important neurodegenerative diseases involve iron overload in brain. Storage of iron is ensured by ferritin, which contains a magnetic core. It causes a darkening on T₂‐weighted MR images. This work aims at improving the understanding of the NMR relaxation of iron‐loaded human tissues, which is necessary to develop protocols of iron content measurements by MRI. Relaxation times measurements on brain, liver and spleen samples were realized at different magnetic fields. Iron content was determined by atomic emission spectroscopy. For all samples, the longitudinal relaxation rate (1/T₁) of tissue protons decreases with the magnetic field up to 1 T, independently of iron content, while their transverse relaxation rate (1/T₂) strongly increases with the field, either linearly or quadratically, or a combination thereof. The extent of the inter‐echo time dependence of 1/T₂ also varies according to the sample. A combination of theoretical models is necessary to describe the relaxation of iron‐containing tissues. This can be due to the presence, inside tissues, of ferritin clusters of different sizes and densities. When considering all samples, a correlation (r² = 0.6) between 1/T₁ and iron concentration is observed at 7.0 T. In contrast the correlation between 1/T₂ and iron content is poor, even at high field (r² = 0.14 at 7.0 T). Our results show that MRI methods based on T₁ or T₂ measurements will easily detect an iron overloading at high magnetic field, but will not provide an accurate quantification of tissue iron content at low iron concentrations. Copyright © 2014 John Wiley & Sons, Ltd.     

Human fetuses are able to mount an adultlike CD8 T-cell response

Fetal/neonatal immune responses generally are considered to be immature and weaker than that of adults. We have studied the cord-blood T cells of newborns congenitally infected with Trypanosoma cruzi, the protozoan agent of Chagas disease. Our data demonstrate a predominant activation of CD8 T cells expressing activation markers and armed to mediate effector functions. The analysis of the T-cell receptor beta chain variable repertoire shows the oligoclonal expansion of these T lymphocytes, indicating that activation was driven by parasite antigens. Indeed, we have detected parasite-specific CD8 T cells secreting interferon-gamma after coincubation with live T cruzi. This response is enhanced in the presence of recombinant interleukin-15, which limits the T-cell spontaneous apoptosis. These findings point out that the fetal immune system is more competent than previously appreciated, since fetuses exposed to live pathogens are able to develop an adultlike immune CD8 T-cell response.     

BRCA1 and BRCA2 Mutations in Ethnic Lebanese Arab Women With High Hereditary Risk Breast Cancer

Purpose.

Breast cancer is the most common malignancy among women in Lebanon and in Arab countries, with 50% of cases presenting before the age of 50 years.

Methods.

Between 2009 and 2012, 250 Lebanese women with breast cancer who were considered to be at high risk of carrying BRCA1 or BRCA2 mutations because of presentation at young age and/or positive family history (FH) of breast or ovarian cancer were recruited. Clinical data were analyzed statistically. Coding exons and intron-exon boundaries of BRCA1 and BRCA2 were sequenced from peripheral blood DNA. All patients were tested for BRCA1 rearrangements using multiplex ligation-dependent probe amplification (MLPA). BRCA2 MLPA was done in selected cases.

Results.

Overall, 14 of 250 patients (5.6%) carried a deleterious BRCA mutation (7 BRCA1, 7 BRCA2) and 31 (12.4%) carried a variant of uncertain significance. Eight of 74 patients (10.8%) aged ≤40 years with positive FH and only 1 of 74 patients (1.4%) aged ≤40 years without FH had a mutated BRCA. Four of 75 patients (5.3%) aged 41–50 years with FH had a deleterious mutation. Only 1 of 27 patients aged >50 years at diagnosis had a BRCA mutation. All seven patients with BRCA1 mutations had grade 3 infiltrating ductal carcinoma and triple-negative breast cancer. Nine BRCA1 and 17 BRCA2 common haplotypes were observed.

Conclusion.

Prevalence of deleterious BRCA mutations is lower than expected and does not support the hypothesis that BRCA mutations alone cause the observed high percentage of breast cancer in young women of Lebanese and Arab descent. Studies to search for other genetic mutations are recommended.     

Immediate breast reconstruction with prostheses after conservative treatment plus intraoperative radiotherapy. long term esthetic and oncological outcomes

Electron intraoperative radiotherapy (ELIOT) has been introduced for breast conservative treatment (BCT) with promising oncological outcome. Thus, immediate breast reconstruction with prosthesis after BCT became possible due to minimal radiation effect on local tissue from ELIOT. We reported oncological and esthetical results of 29 BCT patients who had immediate implant reconstruction plus 21 Gy-ELIOT as the sole radiation treatment. All patients had prosthesis in ipsilateral breast and had simultaneous contralateral augmentation for symmetrical procedure. The average age was 52.3 years. There were stage Ia thirteen cases, stage Ib seven cases, stage IIa six cases and stage IIIb one case and two cases of intraepithelial neoplasia. From 54.2 (36-88) months follow up, the capsular contracture grading in the reconstructed breast from ELIOT-side is comparable with non-irradiated contralateral side. There was one patient who developed local recurrence (LR) and later on dead with breast related event (LR=0.76% per year). There was no primary ipsilateral carcinomas and distant metastasis.     

Prospective, Multicenter, 3-Year Trial of Laparoscopic Adjustable Gastric Banding with the MIDBAND?

Background

Although laparoscopic adjustable gastric banding (LAGB) is a popular metabolic/bariatric procedure, few prospective studies have assessed its outcomes. This study aimed to prospectively assess LAGB safety and effectiveness outcomes using the MIDBAND? (MID, Dardilly, France).

Methods

Between May 2005 and September 2006, 262 morbidly obese patients underwent primary gastric banding with pars flaccida technique in 13 French medical centers. Excess weight loss and change in body mass index (BMI, kilogram per square meter), percentage of patients with comorbidities, and obesity-related complications were recorded. Patients were followed at 6-month intervals for 3?years. A multivariable individual growth model was used to analyze weight change over time and determine potential predictors of weight loss.

Results

The majority of patients were female (n?=?233, 89%), with mean age of 36.4?±?9.7?years. At 3?years, LAGB with MIDBAND resulted in significant decrease in mean BMI from 41.8?±?4.2 to 30.7?±?5.8 (p?p?Conclusion Prospective outcomes demonstrate the safety and efficacy of gastric banding over time using the MIDBAND. Individual growth modeling demonstrated that postoperative weight loss is strongly related to the frequency and consistency of follow-up visits.     

Safety, Feasibility, and Short-Term Outcomes of Single Port Access Colorectal Surgery: A Single Institutional Case-Matched Study

Background  

Feasibility of single port access (SPA) colorectal surgery has been established for various procedures from ileocecal resection to proctectomy. Nevertheless, its benefits compared to conventional laparoscopy still need to be assess. The aim of this study was to compare SPA to conventional colorectal laparoscopic surgery in a single institutional case-matched study.