BACKGROUND AND PURPOSE: A thorough knowledge of fetal growth and development is key to understanding both the normal and abnormal fetal MR imaging findings. We investigated the size and signal intensity of the normal pituitary gland and the intrasphenoidal ossification around the Rathke pouch in formalin-fixed fetuses on MR imaging.

MATERIALS AND METHODS: Thirty-two fetuses with undamaged brains were included in this study (mean age, 19.93 weeks; age range, 12–31 weeks). Visual inspection of the pituitary and ossification around the Rathke pouch in the sphenoid bone or the postsphenoid ossification was conducted. The extent of pituitary and postsphenoid ossification, pituitary/pons signal ratio, and postsphenoidal ossification/sphenoid bone signal ratio was compared according to gestational age.

RESULTS: The pituitary gland was identified as a hyperintense intrasellar structure in all cases, and postsphenoid ossification was identified as an intrasphenoidal hyperintense area in 27 of the 32 cases (84%). The mean pituitary/pons signal ratio was 1.13 ± 0.18 and correlated weakly with gestational age (R2 = 0.243), while the mean postsphenoid ossification/sphenoid bone signal ratio was 2.14 ± 0.56 and did not show any increase with gestational age (R2 = 0.05). No apparent change in the size of pituitary hyperintensity was seen with gestational age (R2 = 0.001). Postsphenoid ossification showed an increase in size with gestational age (R2 = 0.307).

CONCLUSIONS: The fetal pituitary gland was hyperintense on T1-weighted images and the pituitary/pons ratio and extent of postsphenoid ossification correlated weakly with gestational age.

The interest in the use of 3D matrices for in vitro analysis, with a view to increasing the relevance of in vitro studies and reducing the dependence on in vivo studies, has been growing in recent years. Cells grown in a 3D in vitro matrix environment have been reported to exhibit significantly different properties to those in a conventional 2D culture environment. However, comparison of 2D and 3D cell culture models have recently been noted to result in differing responses of cytotoxic assays, without any associated change in viability. The effect was attributed to differing conversion rates and effective concentrations of the resazurin assay in 2D and 3D environments, rather than differences in cellular metabolism. In this study, the efficacy of a chemotherapeutic agent, doxorubicin, is monitored and compared in conventional 2D and 3D collagen gel exposures of immortalized human cervical cells. Viability was monitored with the aid of the Alamar Blue assay and drug internalisation was verified using confocal microscopy. Drug uptake and retention within the collagen matrix was monitored by absorption spectroscopy. The viability studies showed apparent differences between the 2D and 3D culture systems, the differences attributed in part to the physical transition from 2D to a 3D environment causing alterations to dye resazurin uptake and conversion rates. The use of 3D culture matrices has widely been interpreted to result in “reduced” toxicity or cellular “resistance” to the chemotherapeutic agent. The results of this study show that the reduced efficiency of the drug to cells grown in the 3D environment can be accounted for by a sequential reduction of the effective concentration of the test compound and assay. This is due to absorption within the collagen gel inducing a higher uptake of both drug and assay thereby influencing the toxic impact of the drug and conversion rate of resazurin, and. The increased effective surface area of the cell exposed to the drug and assay in the 3D environment. The effect was noted to be higher after shorter exposure periods and should be accounted for in in vitro 2D and 3D culture environment comparisons.

Bioinformatics is a multi-disciplinary science focusing on the applications of computational methods and mathematical statistics to molecular biology. Choosing bioinformatics as specialization gives an opportunity to get involved with the most interesting computational techniques dealing with biological data to contribute to cure and diagnose some of genetic disorders that affect biological machines. The purpose of this library (which defines namespace BioQt), is to provide a set of routines for handling biological sequence data for Qt/C++ users (the full source code available on https://github.com/alrawab/BioQt). This thesis will shed the light on some modules of BioQt SDK such as exact string matching problem, Microsatellite Repeats, Palindromic sequences and sequence alignment algorithms (Longest Common Subsequence, Needleman-Wunsch and Smith-Waterman). This thesis examines and evaluates these challenging problems in bioinformatics by using Qt/C++.

Purpose

To investigate the diffusion tensor imaging parameters of the optic radiation and surrounding structures using the high-resolution readout-segmented diffusion tensor imaging method.

Materials and methods

Coronal readout-segmented diffusion tensor images were acquired in 15 healthy volunteers. On three slices of each image, eigenvalue 1, fractional anisotropy, radial diffusivity, apparent diffusion coefficient, and signal intensity on T2-weighted images were measured in the lateral inferior longitudinal fasciculus, external and internal layers of the optic radiation, and the tapetum within regions of interest delineated by two independent observers. Profile curve analysis of regions of interest across the optic radiation and surrounding structures was performed for a representative typical case.

Results

Significant differences in fractional anisotropy, radial diffusivity and apparent diffusion coefficient were observed between external and internal layers of the optic radiation, while there was no significant difference in eigenvalue 1. In fractional anisotropy maps, two low signal bands were observed between the inferior longitudinal fasciculus, the optic radiation and the tapetum. Profile curve analysis showed a minimum on the fractional anisotropy and eigenvalue 1 images and a maximum in the radial diffusivity image.

Conclusion

Readout-segmented diffusion tensor imaging revealed significant differences in the diffusion tensor imaging parameters between internal and external layers of the optic radiation.

Objective: We qualitatively evaluated the differences among susceptibility-weighted (SWI), magnitude (MAG), and high pass filtered phase (PHA) images in depicting interlobar differences in the appearance of the signal of the corticomedullary junction (CMJ). We conducted quantitative evaluation to validate the qualitative results.

Materials and Methods: We obtained SWI images from 25 preoperative brain tumor patients (12 men, 13 women, aged 19 to 82 years, mean, 52 years). Two trained neuroradiologists evaluated MAG, PHA, and SWI images. Qualitative evaluation of the CMJ signal and quantitative calculation of the relative signal ratio (RSR) percentages between the CMJ and deep white matter (WM) were conducted at 3 different slice levels of the brain independently for 4 different lobes (frontal, parietal, temporal, and occipital) and compared among MAG, PHA, and SWI. The extent of the area of the CMJ signal was graded on a 4-point scale (Grade 3, >75%; Grade 2, 50 to 75%; Grade 1, 25 to 50%; Grade 0, <25%). Data were statistically analyzed using a nonparametric Friedman test.

Results: The Kappa coefficients between the qualitative and quantitative grades were 0.002 for MAG, 0.0047 for PHA, and 0.050 for SWI. Qualitatively, on the PHA images and SWI, grades of the occipital lobes were significantly higher than those of the other lobes (P < 0.005). Quantitatively, PHA images showed statistically significant interlobar differences in RSR percentage values of the CMJ (P = 0.025).

Conclusion: Qualitatively, the appearance of the CMJ differed significantly among the different lobes of the brain on SWI and underlying PHA images but not on MAG images. Quantitatively, only PHA images showed significant interlobar differences in the RSR. PHA images are most sensitive to the CMJ signal contrast due to local paramagnetic iron content.

Abstract

Introduction: The calcific tendinitis is a common to happen around the shoulder, calcific tendinitis of tendons adjacent to the hip is not common like the shoulder. It can present either as acute hip pain and limitation of movement or chronic hip pain. We present two patients one with acute presentation and the other one chronic.

Case report: We present a case series of two patients with calcific tendinitis of the gluteus medius muscle. One patient a 37-year-old male presented with acute severe hip pain associated with a raised temperature, prompting concern about septic arthritis. The second patient presented with chronic hip pain. Calcification of the soft tissues adjacent to the greater trochanter was evident on plain radiographs in both patients. CT and MRI scans excluded septic or inflammatory arthritis in the patient with an acute presentation, the patient's condition settled with analgesia and NSAIDs.

Conclusion: An unusual combination of symptoms and finding mimicking septic arthritis should be considered in patients presenting with acute calcific tendinitis of the hip gluteus medius muscle.

Rationale and Objectives

To optimize visualization of lenticulostriate artery (LSA) by time-of-flight (TOF) magnetic resonance angiography (MRA) with slice-selective off-resonance sinc (SORS) saturation transfer contrast pulses and to compare capability of optimal TOF-MRA and flow-sensitive black-blood (FSBB) MRA to visualize the LSA at 3T.

Materials and Methods

This study was approved by the local ethics committee, and written informed consent was obtained from all the subjects. TOF-MRA was optimized in 20 subjects by comparing SORS pulses of different flip angles: 0, 400°, and 750°. Numbers of LSAs were counted. The optimal TOF-MRA was compared to FSBB-MRA in 21 subjects. Images were evaluated by the numbers and length of visualized LSAs.

Results

LSAs were significantly more visualized in TOF-MRA with SORS pulses of 400° than others (P < .003). When the optimal TOF-MRA was compared to FSBB-MRA, the visualization of LSA using FSBB (mean branch numbers 11.1, 95% confidence interval (CI) 10.0–12.1; mean total length 236 mm, 95% CI 210–263 mm) was significantly better than using TOF (4.7, 95% CI 4.1–5.3; 78 mm, 95% CI 67–89 mm) for both numbers and length of the LSA (P < .0001).

Conclusions

LSA visualization was best with 400° SORS pulses for TOF-MRA but FSBB-MRA was better than TOF-MRA, which indicates its clinical potential to investigate the LSA on a 3T magnetic resonance imaging.

Oxygen causes an increase in the longitudinal relaxation rate of tissues through its T1-shortening effect owing to its paramagnetic properties. Due to such effects, MRI has been used to study oxygen-related signal intensity changes in various body parts including cerebrospinal fluid (CSF) space. Oxygen enhancement of CSF has been mainly studied using MRI sequences with relatively longer time resolution such as FLAIR, and T1 value calculation. In this study, fifteen healthy volunteers were scanned using fast advanced spin echo MRI sequence with and without inversion recovery pulse in order to dynamically track oxygen enhancement of CSF. We also focused on the differences of oxygen enhancement at sulcal and ventricular CSF. Our results revealed that CSF signal after administration of oxygen shows rapid signal increase in both sulcal CSF and ventricular CSF on both sequences, with statistically significant predominant increase in sulcal CSF compared with ventricular CSF. CSF is traditionally thought to mainly form from the choroid plexus in the ventricles and is absorbed at the arachnoid villi, however, it is also believed that cerebral arterioles contribute to the production and absorption of CSF, and controversy remains in terms of the precise mechanism. Our results demonstrated rapid oxygen enhancement in sulcal CSF, which may suggest inhaled oxygen may diffuse into sulcal CSF space rapidly probably due to the abundance of pial arterioles on the brain sulci.

Mercury exposure is associated with increased risk of cardiovascular disease and profound cardiotoxicity. However, the correlation between Hg(2+)-mediated toxicity and alteration in cardiac cytochrome P450s (Cyp) and their dependent arachidonic acid metabolites has never been investigated. Therefore, we investigated the effect of acute mercury toxicity on the expression of Cyp-epoxygenases and Cyp-ω-hydroxylases and their associated arachidonic acid metabolites in mice hearts. In addition, we examined the expression and activity of soluble epoxide hydrolase (sEH) as a key player in arachidonic acid metabolism pathway. Mercury toxicity was induced by a single intraperitoneal injection (IP) of 2.5 mg/kg of mercuric chloride (HgCl₂). Our results showed that mercury treatment caused a significant induction of the cardiac hypertrophy markers, atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP); in addition to Cyp1a1, Cyp1b1, Cyp2b9, Cyp2b10, Cyp2b19, Cyp2c29, Cyp2c38, Cyp4a10, Cyp4a12, Cyp4a14, Cyp4f13, Cyp4f15, Cyp4f16 and Cyp4f18 gene expression. Moreover, Hg(2+) significantly increased sEH protein expression and activity levels in hearts of mercury-treated mice, with a consequent decrease in 14,15-, and 11,12-epoxyeicosatrienoic acids (EETs) levels. Whereas the formation of 14,15-, 11,12-, 8,9-dihydroxyeicosatrienoic acids (DHETs) was significantly increased. In conclusion, acute Hg(2+) toxicity modulates the expression of several Cyp and sEH enzymes with a consequent decrease in the cardioprotective EETs which could represent a novel mechanism by which mercury causes progressive cardiotoxicity. Furthermore, inhibiting sEH might represent a novel therapeutic approach to prevent Hg(2+)-induced hypertrophy.

OBJECTIVE. In a clinical setting, lipoma can sometime show low signal intensity on susceptibility-weighted imaging (SWI) mimicking hemorrhage. The purpose of this study was to evaluate the fat-water interface chemical-shift artifacts between SWI and T2*-weighted imaging with a phantom study and evaluate SWI in lipoma cases.

MATERIALS AND METHODS. SWI, magnitude, high-pass filtered phase, and T2*-weighted imaging of a lard-water phantom were evaluated in the in-phase, out-of phase, and standard partially out-of-phase TE settings used for clinical 3-T SWI (19.7, 20.9, and 20.0 ms, respectively) to identify the most prominent fat-water interface low signal. SWI of five cases of CNS lipoma were retrospectively evaluated by two neuroradiologists.

RESULTS. TE at 19.7 ms (in-phase) showed the minimum fat-water interface low signal in the phase-encoding direction on magnitude, high-pass filtered phase, and SWI. TE at 20.9 ms (out-of-phase) showed the maximum fat-water interface in the phase-encoding direction on magnitude, high-pass filtered phase, and SWI. TE at 20.0 ms (partially out-of-phase) showed more fat-water interface low signal on SWI than on T2*-weighted imaging, especially in the phase-encoding direction. All lipomas in the five patients showed high signal intensity with surrounding peripheral dark rim on SWI.

CONCLUSION. Fat-water interface is more prominent on the standard TE setting used for clinical SWI (20.0 ms) than that of T2*-weighted imaging and shows a characteristic surrounding peripheral low-signal-intensity rim in lipoma. Knowing the fat-water appearance on SWI is important to avoid misinterpreting intracranial lipomas as hemorrhages.