Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 11 de 11
Filter
1.
Basic and Clinical Neuroscience. 2015; 6 (4): 271-284
in English | IMEMR | ID: emr-179390

ABSTRACT

Introduction: Drug craving could be described as a motivational state which drives drug dependents towards drug seeking and use. Different types of self-reports such as craving feeling, desire and intention, wanting and need, imagery of use, and negative affect have been attributed to this motivational state. By using subjective self-reports for different correlates of drug craving along with functional neuroimaging with cue exposure paradigm, we investigated the brain regions that could correspond to different dimensions of subjective reports for heroin craving


Methods: A total of 25 crystalline-heroin smokers underwent functional magnetic resonance imaging [fMRI], while viewing heroin-related and neutral cues presented in a block-design task. During trial intervals, subjects verbally reported their subjective feeling of cue induced craving [CIC]. After fMRI procedure, participants reported the intensity of their [need for drug use] and [drug use imagination] on a 0-100 visual analog scale [VAS]. Afterwards, they completed positive and negative affect scale [PANAS] and desire for drug questionnaire [DDQ] with 3 components of [desire and intention to drug use], [negative reinforcement,] and [loss of control]


Results: The study showed significant correlation between [subjective feeling of craving] and activation of the left and right anterior cingulate cortex, as well as right medial frontal gyrus. Furthermore, the [desire and intention to drug use] was correlated with activation of the left precentral gyrus, left superior frontal gyrus, and left middle frontal gyrus. Subjects also exhibited significant correlation between the [need for drug use] and activation of the right inferior temporal gyrus, right middle temporal gyrus, and right parahippocampal gyrus. Correlation between subjective report of [heroin use imagination] and activation of the cerebellar vermis was also observed. Another significant correlation was between the [negative affect] and activation of the left precuneus, right putamen, and right middle temporal gyrus


Discussion: This preliminary study proposes different neural correlates for various dimensions of subjective craving self-reports. It could reflect multidimensionality of cognitive functions corresponding with drug craving. These cognitive functions could represent their motivational and affective outcomes in a single item [subjective craving feeling] or in self-reports with multiple dissociable items, such as intention, need, imagination, or negative feeling. The new psychological models of drug craving for covering various dimensions of subjective craving self-reports based on their neurocognitive correspondence could potentially modify craving assessments in addiction medicine

2.
IJB-Iranian Journal of Biotechnology. 2015; 13 (1): 1-10
in English | IMEMR | ID: emr-179795

ABSTRACT

Background: multifunctional core-shell magnetic nanocomposite particles with tunable characteristics have been paid much attention for biomedical applications in recent years. A rational design and suitable preparation method must be employed to be able to exploit attractive properties of magnetic nanocomposite particles


Objectives: herein, we report on a simple approach for the synthesis of magnetic mesoporous silica nanocomposite particles [MMSPs], consisted of a Fe[3]O[4] cluster core, a nonporous silica shell and a second shell of the mesoporous silica of suitable sizes for biomedical applications and evaluate their cytotoxicity effects on human cancer prostate cell lines


Materials and Methods: clusters of magnetite [Fe[3]O[4]] nanoparticles were coated by a layer of nonporous silica using Stober method. The coating step was completed by an outer layer of mesoporous silica via template-removing method. Structural properties of MMSPs were investigated by FTIR, HR-S[T]EM, BET, XRD techniques and magnetic properties of MMSPs by VSM instrument. MTT and LDH assays were employed to study the cytotoxicity of MMSPs


Results: obtained results revealed that decreasing the precursor concentration and the reaction time at the nonporous silica shell formation step decreases the thickness of the nonporous silica shell and consequently leads to the formation of smaller MMSPs. The as-prepared MMSPs have a desirable average size of 180 +/- 10 nm, an average pore size of 3.01 nm, a high surface area of 390.4 m[2].g[-1] and a large pore volume of 0.294 cm[3].g[-1]. In addition, the MMSPs exhibited a superparamagnetic behavior and a high magnetization saturation value of 21 +/- 0.5 emu/g. Furthermore, the viability tests of DU-145 cell lines exposed to various concentrations of these particles demonstrated negligible cytotoxicity effects of the asprepared Particles


Conclusions: these results demonstrate interesting properties of MMSPs prepared in this study for biomedical applications

3.
Frontiers in Biomedical Technologies. 2014; 1 (3): 182-192
in English | IMEMR | ID: emr-153605

ABSTRACT

The perception of music relies on many culture-specific factors; nevertheless this is processed by physiological and functional attributes of the brain system. The aim of this study is to evaluate the functional activity of brain during the perception of rhythm and melody in Persian classical music using fMRI. The test consists of two groups of Persian Modal music scales, frequently called Dastgah. Mahour and Homayoun, in two parts of non-rhythmic and rhythmic pieces presented on 19 right-handed non-musicians. The results of this study revealed the brain activities for each of rhythmic and non-rhythmic versions of Mahour and Homayoun Dastgah. For non-rhythmic Mahour, the activation was found in right lingual gyrus, right precuneous cortex, left Inferior frontal gyrus, and left temporal lobe; whereas for rhythmic Mahour, the areas contain left supplementary motor cortex, left superior frontal gyrus, right and left precentral and postcentral gyrus, left supramarginal gyrus, and right temporal pole. The activated regions for non-rhythmic Homayoun include right and left subcallosal cortex, left medial frontal cortex, left anterior cingulate gyrus, and left frontal pole. In contrast, for rhythmic Homayoun, alternative areas including left precentral gyrus, left precuneous cortex, left anterior supramarginal, and left postcentral gyrus were revealed. rhythmic pieces were shown to activate the areas mostly involved in movement while non-rhythmic pieces related to emotional and memory regions. Although, these results are not consistent totally with the previous findings on western music, they are similar to the outcomes performed on eastern cultural subjects

4.
Frontiers in Biomedical Technologies. 2014; 1 (1): 54-60
in English | IMEMR | ID: emr-191536

ABSTRACT

Purpose: Many of the available brachytherapy treatment planning systems in developing countries are not equipped with CT [or MRI] simulator; therefore, 3D treatment planning cannot be performed. In this project a new procedure has been introduced for utilizing the 2D digitally reconstructed radiograph from MRI images in brachytherapy treatment planning. This procedure enables us to localize the tumor volume and delineate the extent of critical structures in vicinity of tumor volume. Methods: Pelvic lymph node chain position was delineated from transverse MRI images, and transferred into Digitally Reconstructed Radiograph [DRR] and then onto the X-ray images obtained from conventional simulator unit. These images were then imported to Brachytherapy treatment planning system to evaluate the dose to be applied to these organs in cervix Brachytherapy. The accuracy of the matching process was evaluated by phantom study, having known 3D geometric information and landmark assertion. Results: The statistical variations obtained from distance mismatch in phantom and patient studies were in the range of clinically applicable error of registration [< 2mm]. The results showed a large variation of the nodal dose when dose calculation is performed based on point B dose which is the geometrical reference point for calculating the dose to the pelvic lymphatic system. The result also shows that the dose to point B is usually underestimated to represent external iliac maximum dose, and overestimated for representation of external iliac minimum dose. Conclusion: The results indicated that the DRR images can produce comparable accuracies in tumor localization reported in 3D MRI or CT based treatment planning procedures. Therefore, this technique could be used as a feasible approach where a 3D treatment planning is not available

5.
Basic and Clinical Neuroscience. 2012; 3 (4): 75-83
in English | IMEMR | ID: emr-146025

ABSTRACT

The attempt to find out if someone is telling a lie has been of human's interest. One of the techniques which is believed to be efficient in future in fMRI [functional Magnetic Resonance Imaging], using which the changes of regional blood flow during the designed paradigm can be recorded. This method has been considered as a better technique for studying lie and deception. For investigating the neural network associated with lying and deception, a task needs to be designed in which participants are instructed to participate in a lie-like situation. In this article, frequently used tasks have been reviewed with their merits and demerits. In addition, a summary of involved neural networks related to lie and deception, according to previous studies, is provided. The goal in future studies is to allocate brain regions associated with lie and deception that are independent of features related to the chosen task


Subject(s)
Magnetic Resonance Imaging/methods , Computer Simulation , Deception , Image Processing, Computer-Assisted , Brain/physiology , Brain/blood supply , Regional Blood Flow
6.
Iranian Journal of Radiology. 2011; 8 (3): 150-156
in English | IMEMR | ID: emr-144175

ABSTRACT

Uterine fibroids are common benign tumors of the female pelvis. Uterine artery embolization [UAE] is an effective treatment of symptomatic uterine fibroids by shrinkage of the size of these tumors. Segmentation of the uterine region is essential for an accurate treatment strategy. In this paper, we will introduce a new method for uterine segmentation in T1W and enhanced T1W magnetic resonance [MR] images in a group of fibroid patients candidated for UAE in order to make a reliable tool for uterine volumetry. Uterine was initially segmented using Fuzzy C-Mean [FCM] method in T1W-enhanced images and some morphological operations were then applied to refine the initial segmentation. Finally redundant parts were removed by masking the segmented region in T1W-enhanced image over the registered T1W image and using histogram thresholding. This method was evaluated using a dataset with ten patients' images [sagittal, axial and coronal views]. We compared manually segmented images with the output of our system and obtained a mean similarity of 80%, mean sensitivity of 75.32% and a mean specificity of 89.5%. The Pearson correlation coefficient between the areas measured by the manual method and the automated method was 0.99. The quantitative results illustrate good performance of this method. By uterine segmentation, fibroids in the uterine may be segmented and their properties may be analyzed


Subject(s)
Humans , Female , Magnetic Resonance Imaging/methods , Embolization, Therapeutic , Uterine Neoplasms , Leiomyoma/ultrastructure
7.
Audiology. 2011; 20 (1): 82-95
in Persian | IMEMR | ID: emr-132044

ABSTRACT

Neuroimaging techniques in audiovisual speech processing are innovative approach to neuroscience investigation that steadily influences the deep survey of highly mechanisms involved in this process. The purpose of this study was to evaluate brain activity via functional magnetic resonance imaging throughout audiovisual speech perception in Persian language. Functional MRI was used to assess 19 normal 20-30 year old women while they had been presented syllable /ka/ visually and /pa/ auditory using block design method, in which it would provide two series of imaging, functional and T1-weighted. Subsequently, the results were analyzed and compared by FSL software. The results of this study pointed out that both middle and cortical regions of brain are activated in visual stimuli and its middle regions are activated in response to auditory stimuli. Hence, left anterior supramarginal, some parts of motor speech system including insular and cingulated cortex-precentral cortex were stimulated with visual stimulus and left posterior supramarginal as well as right supramarginal gyrus were stimulated with auditory stimulus. Moreover, in this investigation, McGurk effect was behaviorally proven in fifteen subjects. It was hypothesized that the activation of unique region, supramarginal gyrus, with both audio and visual stimuli indicated the presence of commonplace region for phonologic processing of sensory inputs. In addition, auditory stimuli develop more intense activity; and on the other hand, broaden-maximum voxel-as well as extra regions are demonstrated in response to visual stimuli. These points represent the unfamiliarity of normal individual brain to percept visual speech stimuli

8.
Basic and Clinical Neuroscience. 2011; 3 (1): 22-29
in English | IMEMR | ID: emr-132584

ABSTRACT

The aim of this study was to get to a neurological evaluation of one of the Persian music scales, Homayoun, on brain activation of non-musician subjects. We selected this scale because Homayoun is one of the main scales in Persian classical music which is similar to minor mode in western scales. This study was performed on 19 right handed subjects, Aging 22-31. Here some pieces from Homayoun Dastgah are used in both rhythmic and non-rhythmic. The results of this study revealed the brain activities for each of rhythmic and non-rhythmic versions of Homayoun Dastgah. The activated regions for non-rhythmic Homayoun contained: right and left Subcallosal Cortex, left Medial Frontal cortex, left anterior Cingulate Gyrus, left Frontal Pole and for rhythmic Homayoun contained: left Precentral Gyrus, left Precuneous Cortex, left anterior Supramarginal, left Superior Parietal Lobule, left Postcentral Gyrus. Also, we acquired amygdala area in both pieces of music. Based on arousal effects of rhythm and Damasio's somatic marker hypothesis, non-rhythmic Homayoun activates regions related to emotion and thinking while activity of rhythmic Homayoun is related to areas of movement and motion


Subject(s)
Humans , Male , Female , Music
9.
Archives of Iranian Medicine. 2010; 13 (3): 223-229
in English | IMEMR | ID: emr-105361

ABSTRACT

Neural correlates of single word reading with the use of a functional MRI [fMRI] scan have been widely studied in different languages. These study patterns of cortical activation differ in different languages. In this report we used a similar technique to study cortical activation when reading single Persian words. The subjects were comprised of nine healthy right-handed bilingual individuals who performed three consecutive fMRI paradigms. Our study showed activation of the inferior frontal gyrus [IFG] when single Persian words were read. These results revealed that the pattern of brain activation during word production in Persian has a similar topography to that of English equivalents. The paradigms selectively activate word production areas and are useful in neurological assessment of the Persian population


Subject(s)
Humans , Male , Magnetic Resonance Imaging/methods , Language , Cerebral Cortex/physiology , Reading , Verbal Behavior/physiology , Sampling Studies
10.
Journal of Family and Reproductive Health. 2010; 4 (3): 105-107
in English | IMEMR | ID: emr-113420

ABSTRACT

To evaluate the potentiality of OVCAR-3 cell line of ovarian adenocarcinoma as a xenograft model for ovarian adenocarcinoma in nude mice. The cell line isolated from advanced human ovarian adenocarcinoma, were inoculated to eight nude mice and two months later. Established tumors were transferred to pathology laboratory to be prepared by H and E staining and immunohistochemical staining with CA125 antibody. Study of H and E slides showed advanced adenocarcinoma. The CA125 Tumor marker was also positive in tumoral tissue. Established tumors showed excellently the characteristics of ovarian adenocarcinoma. This model can be used to evaluate new treatment strategies

11.
AJMB-Avicenna Journal of Medical Biotechnology. 2009; 1 (1): 27-31
in English | IMEMR | ID: emr-90809

ABSTRACT

Conjugation of monoclonal antibodies to super paramagnetic nanoparticles is an effective method for cancer diagnosis and treatment. In this study the humanized anti her2/neu monoclonal antibody- Herceptin- was conjugated to super paramagnetic iron oxide [SPIO] nanoparticles using EDC method. The concentration of the conjugated antibodies was measured by Bradford assay. The antibody-nanoparticle conjugates were incubated with SKBR-3 and T47D human breast carcinoma cell lines and the presence of the conjugates on cell surface was confirmed by Prussian blue iron staining method. Conjugation of Herceptin to SPIO resulted in a precipitate-free conjugate containing 20microg antibody/mg SPIO. Prussian blue iron-staining of cells showed successful binding of the conjugates to the cell surfaces. Conjugation of monoclonal antibodies to SPIO may be a useful method for detection of tumor cells, especially by MRI techniques


Subject(s)
Antibodies, Monoclonal , Iron , Oxides , Receptor, ErbB-2 , Genes, erbB-2
SELECTION OF CITATIONS
SEARCH DETAIL