Search

Abstract All-optical communication systems are under continuous development to address different core elements of inconvenience. Here, we numerically investigate an all-optical modulator, realizing a highly efficient modulation depth of 22 dB and a low insertion loss of 0.32 dB. The tunable optical element of the proposed modulator is a layer of Al-doped Zinc Oxide (AZO), also known as an epsilon-near-zero transparent conductive oxide. Sandwiching the AZO layer between a carefully designed distributed Bragg reflector and a dielectric metasurface—i.e., composed of a two-dimensional periodic array of cubic Si—provides a guided-mode resonance at the OFF state of the modulator, preventing the incident signal reflection at λ = 1310 nm. We demonstrate the required pump fluence for switching between the ON/OFF states of the designed modulator is about a few milli-Joules per cm2. The unique properties of the AZO layer, along with the engineered dielectric metasurface above it, change the reflection from 1 to 93%, helping design better experimental configurations for the next-generation all-optical communication systems.

Abstract Rosai‐Dorfman disease (RDD), as a lymphoproliferative disorder with unknown etiology, is commonly identified with systemic clinical manifestations in various organs. In this case study, RDD occurrence was reported with an exceedingly liver mass.

Background and Purpose: Cognitive impairment (CI) is one of the most notable disabilities of Parkinson’s disease that is associated with lower quality of life. Early detection of CI is therefore very important for these patients. The purpose of this study was to examine the relationship between cognitive function and the metabolic data from magnetic resonance spectroscopy (MRS) of the patient suffering with Parkinson’s disease. Methods: Totally, 45 patients with Parkinson’s disease were used in this study. Subjects were divided into three groups based on scales for outcome from Parkinson cognition (SCOPACOG) test. Patients were classified as non-cognitive impairment (NCI; n=15), mild cognitive impairment (MCI; n=15) and dementia (PDD; n=15). All subjects underwent MRI and 1 H-MRS techniques and metabolic changes such as NAA/Cr and NAA/Cho ratios, which were measured in the left hippocampal area of the brain. Results: The mean and standard deviation of the NAA/Cr ratio in the three cognitive groups (NCI, MCI, PDD) were (2.51±0.037), (2.50±0.033) and (2.47±0.025), respectively. ANOVA test showed a significant difference in the three groups. Furthermore, the Scheffé test showed a significant difference between patients in the MCI and PDD groups (p=0.01). There was no significant difference between the non-cognitive impairment and mild cognitive impairment groups (p=0.54). No significant difference was found in NAA/Cho ratio (p=091). Conclusion: A decreasing NAA/Cr ratio has influence on cognitive function and the development of severe cognitive dysfunction in Parkinson suffering patients. Furthermore, 1 H-MRS determinant can be useful to evaluate cognition in Parkinson patients.

Introduction: Recently, hepatoma-derived growth factor (HDGF) has been considered as a significantly important factor in determining the prognosis and estimating the probability of tumor cell invasions, recurrence, and lymph node metastasis in different cancers, including breast malignancies. Materials and Methods: Immunohistochemistry (IHC) study for HDGF was performed on paraffin-embedded blocks of patients with breast carcinoma in Modarres hospital, Tehran, Iran, since 1387–1390 (74 cases); three separate pathologists read the slides after complete IHC staining. Thereafter, necessary information was recorded from patient files, and eventually, findings were analyzed by SPSS program. Results: Expression of nuclear HDGF has significant statistical correlation with tumor grade according to Nottingham grading scheme; this correlation is also seen with nuclear pleomorphism of tumor cells and mitotic count. No correlation between age and tumor size with expression of HDGF is found. Lymph node metastasis is in inverse ratio to nuclear HDGF staining. Conclusion: Nuclear expression of HDGF in tumor cells is increased concordantly to tumor grade, which implies us to the role of this marker in determining the prognosis and choosing the most suitable treatment plan.

The presence of different autoimmune disorders in the same individual is called multiple autoimmune syndrome (MAS). One of these co-occurring conditions is autoimmune haemolytic anaemia (AIHA), which is characterized by the production of autoantibodies against red blood cells due to immune system malfunction and which results in severe tissue oxygenation disturbance. AIHA is not uncommon but occurs rarely in MAS; if it does, MAS is then classified as MAS type III. Herein, we describe a case of MAS type III including AIHA which was successfully treated with hydrocortisone with gradual resolution of symptoms.

Ankylosing Spondylitis (AS) is a chronic inflammatory disease of the skeleton manifested by back pain and progressive stiffness of the spine. In AS, the inflammation starts around the enthesis (the site of ligament insertion into bone) and typically affects young men with a peak age of onset of 20 to 30 years. Although classically thought as a spinal disease, it can involve other organs such as eyes, lungs, and heart. We present a 49-year-old man with pleural effusion and history of recent pericardial effusion but his fluid studies of pleura and pericardium did not lead us to a clear diagnosis. Then we noticed his thoracic kyphosis, severe restriction of lumbar movements and sacroiliac joint inflammation on MRI which are suggestive of AS. We started prednisolone 50 mg daily for one week and the pleural effusion resolved spontaneously after one week. Then, we tapered prednisolone and the patient remained well off any medication. Isolated pleural and or pericardial effusion may be seen in patients with AS without a simultaneous apical fibrobullous involvement of the lungs and it responds well to corticosteroid.

Background and purpose: Cognitive impairment (CI) is one of the causes of disabilities in multiple sclerosis patients (MS). Therefore, early detection and evaluation of cognitive performance is very important in patients with MS. The aim of the present study is to compare Montreal Cognitive Assessment (MoCA) test and Mini Mental Status Exam (MMSE) in Relapsing Remitting (RR) MS patients. Methods: Fifty RRMS patients who met inclusion and exclusion criteria were recruited in this study. MMSE and MoCA were administrated to all subjects. Also demographic data, disease duration and EDSS were recorded. The results of both tests were compared. Results: The mean score of MoCA and MMSE was 22.86±3.85 and 27.64±2, with a significant difference (p

Background and Purpose: The increased risk for cognitive defects in individuals affected by metabolic syndrome especially in those patients with cardiovascular disorders is now claimed. We aimed to assess the relationship between cognitive performance and the various components of metabolic syndrome. Methods: One hundred and eighteen consecutive individuals aged 30 to 86 years were included into this cross-sectional survey. The metabolic syndrome and its definitive components were defined according to the definition described in the Framingham Heart Study by NCEP ATP III criteria. The Montreal Cognitive Assessment (MOCA) questionnaire was employed to cognitive screening. Results: Those patients with metabolic syndrome had significantly lower mean MOCA score compare to the group without metabolic syndrome (19.11 ± 5.49 versus 21.28 ± 4.56, p = 0.021). Among all cognition sub domains, the mean attention score was significantly lower in the group with metabolic syndrome than in another group. In a multivariate linear regression model adjusting sex and age variables showed that the presence of metabolic syndrome could effectively predict cognitive impairment (beta = -2.202, SE = -0.214, p = 0.013). Conclusion: The presence of metabolic syndrome can be mainly related to damaging cognition especially impairing the power of attention.

Background and Purpose: Because of well-established role of obesity in brain lesions, progressing cognitive deficits in obese patients has been recently suggested. In current study and for the first time, we aimed to assess cognition status in Iranian obese people and to compare it with non-obese individuals. Methods: One hundred and eighteen consecutive patients with the different cardiovascular and metabolic primary complaints were assigned to obese group (n=25, 21.2%) and non-obese group (n=93, 78.8%). Cognitive status was assessed at initial visit using the Montreal Cognitive Assessment (MoCA) questionnaire. Results: Mean of total cognitive score in obese patients was 20.04±4.57 and in non-obese ones was 20.19±5.32 with no difference (p=0.886). In total, 8.0% of obese patients and 20.4% of non-obese patients had normal cognitive function (p=0.149). No significant difference was also found in different subdomains of cognitive ability between obese and non-obese groups. None of the cognitive domains had significant association with BMI as the considered indicator for defining obesity. Based on multivariate linear regression modeling, obesity could not predict cognitive deficit (beta=0.034, SE:1.10 p=0.973). Conclusion: Our survey could not demonstrate an association between obesity and cognitive impairment in a sample of Iranian patients.

Cerebral stroke is a rare disease in children. Moyamoya (MM) is one of the infrequent cerebrovascular diseases with unknown etiology. We report an 8 year-old-boy with chief complain of sudden onset bilateral parietal lobe headache. He mentioned that his headache was first started about three weeks ago and was associated with visual disturbance. His mother declared that the boy developed gait problems few days later and only could walk with assistance. He was diagnosed with MM disease. After, medical treatment his symptoms were mildly improved and because of his family disagreement cerebral revascularization surgery was not performed.

To perform an accurate approach to the spine specially for fracture stabilization a 3D model of spine surgical region may improve this mechanism and it can help the surgeon to have a deeper glance to this scenario. The pre-op planning facility is another advantage of the patient spine specific model to take a chance of making guides to direct pedicle screws safely and increase the pathomechanics of volumes of interest stability factor parallel with its mobility restoration. There are some algorithms for making 3D-reconstruction from CT or MR data-set but the main goal of in-vivo component 3D making is right component extraction from its peripheral segments to achieve the best judgment especially about the surgical approach. Here is a cervical vertebral bodies segmentation and 3D-reconstruction of two cervical adjacent levels combined with the registration process that is shown the intervertebral degree regarding to range of motion percent.

Kennedy disease is a rare X-linked neurodegenerative disorder that affects patients in 30-50 years of age. It is caused by CAG-repeat in androgen receptor gen. There is no known effective treatment for Kennedy disease. We report a 60-year-old man who had fasciculations and proximal and distal muscle weakness. Physical examination showed involvement of the bulbar musculature accompanied by tongue atrophy and perioral muscle weakness. Furthermore, he had bilateral gynecomastia. Laboratory and imaging findings were normal, except electromyography that showed chronic proximal and distal denervation. Finally, the patient diagnosed with Kennedy disease according to clinical presentation and EMG abnormality that confirmed with genetic study.