7T-guided super-resolution of 3T MRI

Bahrami, Khosro,Shi, Feng,Rekik, Islem,Gao, Yaozong,Shen, Dinggang Published for the American Association of Physicis 2017 Medical physics Vol.44 No.5

<P>Conclusions: We propose a novel method for prediction of high-resolution 7T-like MR images from low-resolution 3T MR images. Our predicted 7T-like MR images demonstrate better spatial resolution compared to 3T MR images, as well as prediction results by other comparison methods. Such high-quality 7T-like MR images could better facilitate disease diagnosis and intervention. (C) 2017 American Association of Physicists in Medicine</P>

Ketanserin and Naftopidil Enhance the Potentiating Effect of Alpha-Methyl-Serotonin on the Neurally-Induced Contraction of Human Isolated Urinary Bladder Muscle Strips

Tsuyoshi Hattori,Philippe Lluel,Céline Rouget,Moèz Rekik,Mitsuharu Yoshiyama 대한배뇨장애요실금학회 2017 International Neurourology Journal Vol.21 No.1

Purpose: The aim of this study was to assess the potential involvement of a specific subtype of 5-hydroxytryptamine (5-HT), 5HT2 receptors in neurally-induced contractions of the human detrusor. Methods: Contractile responses to electrical field stimulation (EFS) were examined in human isolated urinary bladder muscle strips. The potentiation of EFS-induced detrusor contraction was examined by adding cumulative concentrations of a 5-HT and 5-HT2 receptor agonist, α-methyl-serotonin (α-Me-5-HT) (1nM–100μM) in the presence or absence of a 5-HT2 antagonist, ketanserin (5-HT2A>5-HT2C) or naftopidil (5-HT2B>5-HT2A) (0.3–3μM). Results: 5-HT and α-Me-5-HT potentiated EFS-induced contraction with a maximal effect (Emax) of 37.6% and 38.6%, respectively, and with pEC50 (negative logarithm of the concentration required for a half-maximal response to an agonist) values of 8.3 and 6.8, respectively. Neither ketanserin nor naftopidil at any concentration produced a rightward displacement of the α-Me-5-HT concentration response curve. Instead, the Emax of α-Me-5-HT increased in the presence of ketanserin at 0.3–1μM and in the presence of naftopidil at 1μM to 51% and 56%, respectively, while the Emax in the presence of vehicle alone was 36%. The highest concentration (3μM) of either drug, however, fully reversed the enhancement. Conclusions: The potentiating effect of α-Me-5-HT on neurally-induced contraction of human urinary bladder muscle strips was not found to be mediated via any 5-HT2 receptor subtypes. The underlying mechanism for the enhancement of the α-Me- 5-HT potentiating effect on detrusor contractility by ketanserin and naftopidil remains unknown; however, our results suggest that these drugs may be useful for treating contractile dysfunction of the detrusor, as manifested in conditions such as underactive bladder.

Genetic analysis of milk production traits of Tunisian Holsteins using random regression test-day model with Legendre polynomials

Zaabza, Hafedh Ben,Gara, Abderrahmen Ben,Rekik, Boulbaba Asian Australasian Association of Animal Productio 2018 Animal Bioscience Vol.31 No.5

Objective: The objective of this study was to estimate genetic parameters of milk, fat, and protein yields within and across lactations in Tunisian Holsteins using a random regression test-day (TD) model. Methods: A random regression multiple trait multiple lactation TD model was used to estimate genetic parameters in the Tunisian dairy cattle population. Data were TD yields of milk, fat, and protein from the first three lactations. Random regressions were modeled with third-order Legendre polynomials for the additive genetic, and permanent environment effects. Heritabilities, and genetic correlations were estimated by Bayesian techniques using the Gibbs sampler. Results: All variance components tended to be high in the beginning and the end of lactations. Additive genetic variances for milk, fat, and protein yields were the lowest and were the least variable compared to permanent variances. Heritability values tended to increase with parity. Estimates of heritabilities for 305-d yield-traits were low to moderate, 0.14 to 0.2, 0.12 to 0.17, and 0.13 to 0.18 for milk, fat, and protein yields, respectively. Within-parity, genetic correlations among traits were up to 0.74. Genetic correlations among lactations for the yield traits were relatively high and ranged from $0.78{\pm}0.01$ to $0.82{\pm}0.03$, between the first and second parities, from $0.73{\pm}0.03$ to $0.8{\pm}0.04$ between the first and third parities, and from $0.82{\pm}0.02$ to $0.84{\pm}0.04$ between the second and third parities. Conclusion: These results are comparable to previously reported estimates on the same population, indicating that the adoption of a random regression TD model as the official genetic evaluation for production traits in Tunisia, as developed by most Interbull countries, is possible in the Tunisian Holsteins.

Automatic brain labeling via multi-atlas guided fully convolutional networks

Fang, Longwei,Zhang, Lichi,Nie, Dong,Cao, Xiaohuan,Rekik, Islem,Lee, Seong-Whan,He, Huiguang,Shen, Dinggang Elsevier 2019 Medical image analysis Vol.51 No.-

<P><B>Abstract</B></P> <P>Multi-atlas-based methods are commonly used for MR brain image labeling, which alleviates the burdening and time-consuming task of manual labeling in neuroimaging analysis studies. Traditionally, multi-atlas-based methods first register multiple atlases to the target image, and then propagate the labels from the labeled atlases to the unlabeled target image. However, the registration step involves non-rigid alignment, which is often time-consuming and might lack high accuracy. Alternatively, patch-based methods have shown promise in relaxing the demand for accurate registration, but they often require the use of hand-crafted features. Recently, deep learning techniques have demonstrated their effectiveness in image labeling, by automatically learning comprehensive appearance features from training images. In this paper, we propose a <I>multi-atlas guided fully convolutional network (MA-FCN)</I> for automatic image labeling, which aims at further improving the labeling performance with the aid of prior knowledge from the training atlases. Specifically, we train our MA-FCN model in a patch-based manner, where the input data consists of <I>not only</I> a training image patch <I>but also</I> a set of its neighboring (i.e., most similar) affine-aligned atlas patches. The guidance information from neighboring atlas patches can help boost the discriminative ability of the learned FCN. Experimental results on different datasets demonstrate the effectiveness of our proposed method, by significantly outperforming the conventional FCN and several state-of-the-art MR brain labeling methods.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Additional atlas intensity and corresponding label information are used to help the MA-FCN model to better label the target ROIs. </LI> <LI> The additional anatomical structural information is revised in the unique pathway in the MA-FCN model. </LI> <LI> The fusion of atlas information is in a hierarchical way. </LI> <LI> The proposed method does not need a non-rigid registration step for aligning atlases to the target image, which is efficient for brain labeling. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Tuberculous and Brucellar Spondylodiscitis: Comparative Analysis of Clinical, Laboratory, and Radiological Features

Hammami Fatma,Koubaa Makram,Feki Wiem,Chakroun Amal,Rekik Khaoula,Smaoui Fatma,Marrakchi Chakib,Mnif Zeineb,Jemaa Mounir Ben 대한척추외과학회 2021 Asian Spine Journal Vol.15 No.6

Study Design: This was a retrospective study. Purpose: The aim was to compare the clinical, laboratory, radiological, and evolutionary features of tuberculous spondylodiscitis (TS) and brucellar spondylodiscitis (BS). Overview of Literature: Clinical presentation of spondylodiscitis varies according to the underlying etiology, among which brucellosis and tuberculosis represent the primary cause, in endemic countries. Only a few studies have compared the characteristics between TS and BS. Methods: A retrospective study was conducted using the data of all patients hospitalized for TS and BS in the infectious diseases department between 1991 and 2018. Results: Among a total of 117 patients, 73 had TS (62.4%) and 44 had BS (37.6%). Females were significantly more affected with TS than males (56.2% vs. 22.7%, p <0.001). Fever (72.7% vs. 45.2%, p =0.004) and sweating (72.7% vs. 47.9%, p =0.009) were significantly more frequent among patients with BS. The median erythrocyte sedimentation rate was significantly higher in the TS group (median, 70 mm/hr; interquartile range [IQR], 45–103 mm/hr) than in the BS group (median, 50 mm/hr; IQR, 16–75 mm/hr) (p =0.003). Thoracic involvement was significantly more frequent in the TS group (53.4% vs. 34.1%, p =0.04), whereas lumbar involvement was significantly more frequent in the BS group (72.7% vs. 49.3%, p =0.01). Initial imaging findings revealed significantly higher frequencies of posterior vertebral arch involvement, vertebral compaction, and spinal cord compression in the TS group. Percutaneous abscess drainage (20.5% vs. 2.3%, p =0.005) and surgical treatment (17.8% vs. 2.3%, p =0.01) were more frequently indicated in the TS group, with a significant difference. Conclusions: A combination of clinical, laboratory, and radiological features can be used to distinguish between TS and BS while these patients await diagnosis confirmation.

Neurological Characteristics of Allgrove Syndrome: A Case Series

Dhoha Ben Salah,Mouna Elleuch,Oumeyma Trimeche,Asma Zargni,Fakhri Kallabi,Salma Sakka,Fatma Mnif,Nabila Rekik,Nadia Charfi,Hassen Kamoun,Mouna Mnif Feki,Faten Hadj Kacem,Mohamed Abid 대한소아신경학회 2024 대한소아신경학회지 Vol.32 No.2

Purpose: Allgrove syndrome, also known as “triple A” syndrome, is characterized by adrenal insufficiency, achalasia, and alacrimia. When neurological signs are also present, the condition is referred to as “4 A” syndrome. Methods: We conducted a retrospective analysis of three patients with 4 A syndrome confirmed genetically. A complete neurological exam was carried out by an experimented neurologist. Results: Herein, we describe the neurological characteristics often associated with this condition, through the clinical and electrophysiological analysis of three patients. All patients exhibited a mutation in AAAS, the gene coding for ALADIN. While these individuals presented with the classic features of triple-A syndrome, neurological symptoms were not prominent. Conclusion: The neurological manifestations of Allgrove syndrome have historically been overlooked and inadequately explored. Due to the condition’s rarity and substantial phenotypic heterogeneity, only recently have a variety of symptoms been recognized and described.