Investigation of breast cancer using two‐dimensional MRS

Proton (¹H) MRS enables non‐invasive biochemical assay with the potential to characterize malignant, benign and healthy breast tissues. In vitro studies using perchloric acid extracts and ex vivo magic angle spinning spectroscopy of intact biopsy tissues have been used to identify detectable metabolic alterations in breast cancer. The challenges of ¹H MRS in vivo include low sensitivity and significant overlap of resonances due to limited chemical shift dispersion and significant inhomogeneous broadening at most clinical magnetic field strengths. Improvement in spectral resolution can be achieved in vivo and in vitro by recording the MR spectra spread over more than one dimension, thus facilitating unambiguous assignment of metabolite and lipid resonances in breast cancer. This article reviews the recent progress with two‐dimensional MRS of breast cancer in vitro, ex vivo and in vivo. The discussion includes unambiguous detection of saturated and unsaturated fatty acids, as well as choline‐containing groups such as free choline, phosphocholine, glycerophosphocholine and ethanolamines using two‐dimensional MRS. In addition, characterization of invasive ductal carcinomas and healthy fatty/glandular breast tissues non‐invasively using the classification and regression tree (CART) analysis of two‐dimensional MRS data is reviewed. Copyright © 2008 John Wiley & Sons, Ltd.     

Hook plate fixation for type II fractures of the lateral end of the clavicle

Management of type II fractures of the lateral end of the clavicle is controversial. Different treatment options have been advocated with varying results. In this paper, we report the results of a group of 22 patients who underwent hook plate fixation for these fractures between 1997 and 2004. The mean follow-up was 39 months. There were 4 significant complications. Twenty-one patients regained their preinjury level of activity, and 19 patients were satisfied with their outcome. We recommend hook plate fixation as an acceptable alternative method for the treatment of type II fractures of the lateral end of the clavicle.     

Adiabatic localized correlation spectroscopy (AL-COSY): application in muscle and brain

Purpose:

To describe an enhanced version of a localized correlation spectroscopy (L‐COSY) by introducing adiabatic radiofrequency (RF) pulses for localization in two dimensions. Adiabatic pulses will improve slice selection profile and reduce chemical shift artifacts. Optimized Mao and adiabatic hyperbolic secant pulses are tested in vivo.

Materials and Methods:

Region of interest is localized by a 90° nonselective adiabatic RF pulse followed by two pairs of adiabatic RF pulses and a terminal 90° RF sinc pulse. Slice profiles for both refocusing pulses and chemical shift artifacts are measured in a water–oil phantom for L‐COSY and AL‐COSY. In vivo results of both COSY sequences are shown from muscle and brain on a 3 Tesla (T) scanner.

Results:

Chemical shift artifacts were reduced with AL‐COSY compared with L‐COSY. Slice profiles of adiabatic pulses were found to be sharper and more symmetrical than those of traditional Mao pulses. One‐dimensional (1D) phantom studies showed longer T2 values using AL‐COSY sequence. Comparison of 2D spectra obtained revealed spectroscopic peak volume improvements in AL‐COSY and less residual water. In vivo 1D comparison showed more inphase and sharper peaks in AL‐COSY spectrum.

Conclusion:

The AL‐COSY sequence is an improved sequence due to sharper slice selection profiles, reduction of chemical shift artifacts, peak volume improvements in 2D techniques, and less J‐modulation. J. Magn. Reson. Imaging 2011;33:1447–1455. © 2011 Wiley‐Liss, Inc.     

Six fucose‐α(1–2) sugars and α‐fucose assigned in the human brain using in vivo two‐dimensional MRS

A growing body of literature has indicated that fucose‐α(1–2)‐galactose sugars are implicated in the molecular mechanisms that underlie neuronal development, learning and memory in the human brain. An understanding of the in vivo roles played by these terminal fucose residues has been hampered by the lack of technology to non‐invasively monitor their levels in the human brain. We have implemented in vivo two‐dimensional MRS technology to examine the human brain in a 3‐T clinical MR scanner, and report that six fucose‐α(1–2)‐galactose residues and free α‐fucose are available for inspection. Fucose‐α(1–3)‐galactose residues cannot yet be assigned using this technology as they resonate under the water resonance. This new application offers an unprecedented insight into the molecular mechanisms by which fucosylated sugars contribute to neuronal processes and how they alter during development, ageing and disease. Copyright © 2014 John Wiley & Sons, Ltd.     

Incidence and management of male urethritis in the district of Tunis

BACKGROUND: The aim of the study was to evaluate the incidence of male urethritis and the relative frequency of the different etiological agents in order to adapt standard case management. METHODS: The incidence of urethritis has been estimated with a postal study made on a sample of druggists (1/10) of the area. The total observation period was four weeks. The relative frequency of the etiological agents and the positive predictive value (PPV) of the therapeutic approach based on antibiotic treatment of gonorrhoea and Chlamydia trachomatis was achieved on 92 cases of male urethritis attending general physicians in two polyclinics. RESULTS: The annual incidence of male urethritis was estimated at 680 per 100,000. The relative frequency of etiological agents was as 34.7% for Neisseria gonorrhoea, 7.6% for Chlamydia trachomatis and was found at 3.3% for Trichomonas vaginalis; the PPV was only 43% because of the high proportion of negative results reported by the laboratory. CONCLUSION: Gonococcal urethritis incidence tends to decrease regarding non gonococcal urethritis and the therapeutic approach appears to be warranted.