CBCT findings of periapical cemento-osseous dysplasia: A case report

Amir Eskandarloo,Faezeh Yousefi1 대한영상치의학회 2013 Imaging Science in Dentistry Vol.43 No.3

Periapical cemento-osseous dysplasia (PCOD) is a subtype of cemento-osseous dysplasia that usually occurs in middleaged black women. This report described a case of a 45-year-old Iranian woman who was diagnosed with PCOD on the basis of cone beam computed tomographic (CBCT) findings. CBCT enabled detailed visualization of the bone changes. This report described the special radiographic characteristics of PCOD, including discontinuity of the lingual cortex on the CBCT sectional and three-dimensional images.

Position of impacted mandibular third molar in different skeletal facial types: First radiographic evaluation in a group of Iranian patients

Abbas Shokri,Majid Mahmoudzadeh,Maryam Baharvand,Hamed Mortazavi,Javad Faradmal,Samira Khajeh,Faezeh Yousefi1,Maruf Noruzi-Gangachin 대한영상치의학회 2014 Imaging Science in Dentistry Vol.44 No.1

Purpose: This study was performed to evaluate the position of impacted mandibular third molars in different skeletal facial types among a group of Iranian patients. Materials and Methods: A total of 400 mandibular third molars in 200 subjects with different types of facial growth were radiographically investigated for their positions according to their types of facial growth on the basis of the β angle. The subjects were divided into three groups (class I, II, and III) according to ANB angle, representing the anteroposterior relationship of the maxilla to the mandible. Meanwhile, the subjects were also divided into three groups (long, normal, and short face) according to the angle between the stella-nasion and mandibular plane (SNGoGn angle). ANOVA was used for statistical analysis. Results: The mean βangle showed no significant difference among class I, II, and III malocclusions (df=2, F=0.669, p=0.513). The same results were also found in short, normal, and long faces (df=1.842, F=2, p=0.160). The mesioangular position was the most frequent one in almost all of the facial growth patterns. Distoangular and horizontal positions of impaction were not found in the subjects with class III and normal faces. In the long facial growth pattern, the frequency of vertical and distoangular positions were not different. Conclusion: In almost all of the skeletal facial types, the mesioangular impaction of the mandibular third molar was the most prevalent position, followed by the horizontal position. In addition, βangle showed no significant difference in different types of facial growth.. Purpose: This study was performed to evaluate the position of impacted mandibular third molars in different skeletal facial types among a group of Iranian patients. Materials and Methods: A total of 400 mandibular third molars in 200 subjects with different types of facial growth were radiographically investigated for their positions according to their types of facial growth on the basis of the β angle. The subjects were divided into three groups (class I, II, and III) according to ANB angle, representing the anteroposterior relationship of the maxilla to the mandible. Meanwhile, the subjects were also divided into three groups (long, normal, and short face) according to the angle between the stella-nasion and mandibular plane (SNGoGn angle). ANOVA was used for statistical analysis. Results: The mean βangle showed no significant difference among class I, II, and III malocclusions (df=2, F=0.669, p=0.513). The same results were also found in short, normal, and long faces (df=1.842, F=2, p=0.160). The mesioangular position was the most frequent one in almost all of the facial growth patterns. Distoangular and horizontal positions of impaction were not found in the subjects with class III and normal faces. In the long facial growth pattern, the frequency of vertical and distoangular positions were not different. Conclusion: In almost all of the skeletal facial types, the mesioangular impaction of the mandibular third molar was the most prevalent position, followed by the horizontal position. In addition, βangle showed no significant difference in different types of facial growth.

Simulating the behavior of patients who leave a public hospital emergency department without being seen by a physician: a cellular automaton and agent-based framework

Yousefi, Milad,Yousefi, Moslem,Fogliatto, F.S.,Ferreira, R.P.M.,Kim, J.H. Associação Brasileira de Divulga&cce 2018 Brazilian journal of medical and biological resear Vol.51 No.3

<P>The objective of this study was to develop an agent based modeling (ABM) framework to simulate the behavior of patients who leave a public hospital emergency department (ED) without being seen (LWBS). In doing so, the study complements computer modeling and cellular automata (CA) techniques to simulate the behavior of patients in an ED. After verifying and validating the model by comparing it with data from a real case study, the significance of four preventive policies including increasing number of triage nurses, fast-track treatment, increasing the waiting room capacity and reducing treatment time were investigated by utilizing ordinary least squares regression. After applying the preventing policies in ED, an average of 42.14% reduction in the number of patients who leave without being seen and 6.05% reduction in the average length of stay (LOS) of patients was reported. This study is the first to apply CA in an ED simulation. Comparing the average LOS before and after applying CA with actual times from emergency department information system showed an 11% improvement. The simulation results indicated that the most effective approach to reduce the rate of LWBS is applying fast-track treatment. The ABM approach represents a flexible tool that can be constructed to reflect any given environment. It is also a support system for decision-makers to assess the relative impact of control strategies.</P>

Biochemical characterization of a hemolymph phenoloxidase and its endogenous inhibitor in the larvae of an invasive moth, Cydalima perspectalis Walker (Lepidoptera: Crambidae)

Yousefi-Lardeh Leila,Zibaee Arash 한국응용곤충학회 2020 Journal of Asia-Pacific Entomology Vol.23 No.4

Phenoloxidase system is a crucial component of insect innate immunity which contribute to oxidize phenols to quinones and to generate reactive oxygen and nitrogen intermediates. In the current study, a phenoloxidase (PO) was extracted by hemocyte lysate preparation and purified through ammonium sulfate precipitation, Sepharyl G-100, and DEAE-Cellulose fast flow columns. At the end of the purification process, an enzyme was purified with a specific activity of 0.462 U/mg protein, recovery of 40.47%, purification fold of 14.43 and molecular weight of ~78.7 kDa. The optimal activity was recorded at pH 7 while the optimal temperature was recorded at 30–35 °C, 35 °C and 25–35 °C, using L-dihydroxyphenylalanine, hydroquinone, and pyrocatechol, respectively. The highest V max of PO was obtained using L-dopa while the lowest K m value was gained using hydroquinone. Among used synthetic inhibitors of ethylenediaminetetraacetic acid (EDTA), diethyldithiocarbamate (DTC), N, N,N0,N0-tetraacetic acid (EGTA) and triethylenetetramine hexaacetic acid (TTHA), EDTA and DTC inhibited more than 60% of the enzyme activity. Moreover, an endogenous phenoloxidase inhibitor (POI) was purified by twice processing of Sepharyl G-100 chromatography with the molecular weight of ~52 kDa. The IC 50 of POI was found 31.3 mg against the purified PO of C. perspectalis and led to a higher value of K m . Finally, larval injection by DTC and POI demonstrated significant inhibition of PO over the time of exposure. A comprehensive understanding of insect’s POs may better clarify the ways of their survival within infected areas and to potentially target them by specific and selective compounds.

Embryonic stem cell interactomics: the beginning of a long road to biological function.

Yousefi, Maram,Hajihoseini, Vahid,Jung, Woojin,Hosseinpour, Batol,Rassouli, Hassan,Lee, Bonghee,Baharvand, Hossein,Lee, KiYoung,Salekdeh, Ghasem Hosseini Humana Press 2012 Stem cell reviews and reports Vol.8 No.4

<P>Embryonic stem cells (ESCs) are capable of unlimited self-renewal while maintaining pluripotency. They are of great interest in regenerative medicine due to their ability to differentiate into all cell types of the three embryonic germ layers. Recently, induced pluripotent stem cells (iPSCs) have shown similarities to ESCs and thus promise great therapeutic potential in regenerative medicine. Despite progress in stem cell biology, our understanding of the exact mechanisms by which pluripotency and self-renewal are established and maintained is largely unknown. A better understanding of these processes may lead to discovery of alternative ways for reprogramming, differentiation and more reliable applications of stem cells in therapies. It has become evident that proteins generally function as members of large complexes that are part of a more complex network. Therefore, the identification of protein-protein interactions (PPI) is an efficient strategy for understanding protein function and regulation. Systematic genome-wide and pathway-specific PPI analysis of ESCs has generated a network of ESC proteins, including major transcription factors. These PPI networks of ESCs may contribute to a mechanistic understanding of self-renewal and pluripotency. In this review we describe different experimental approaches for the identification of PPIs along with various databases. We discuss biological findings and technical challenges encountered with interactome studies of pluripotent stem cells, and provide insight into how interactomics is likely to develop.</P>

ON THE HEREDITARILY HYPERCYCLIC OPERATORS

Yousefi, Bahman,Farrokhinia, Ali Korean Mathematical Society 2006 대한수학회지 Vol.43 No.6

Let X be a separable Banach space. We give sufficient conditions under which $T:X{\rightarrow}X$ is hereditarily hypercyclic. Also, we prove that hereditarily hypercyclicity with respect to a special sequence implies the hereditarily hypercyclicity with respect to the entire sequence.

A Study of Connectivity in MIMO Fading Ad-Hoc Networks

Yousefi'zadeh, H.,Jafarkhani, H.,Kazemitabar, J. The Korea Institute of Information and Commucation 2009 Journal of communications and networks Vol.11 No.1

We investigate the connectivity of fading wireless ad-hoc networks with a pair of novel connectivity metrics. Our first metric looks at the problem of connectivity relying on the outage capacity of MIMO channels. Our second metric relies on a probabilistic treatment of the symbol error rates for such channels. We relate both capacity and symbol error rates to the characteristics of the underlying communication system such as antenna configuration, modulation, coding, and signal strength measured in terms of signal-to-interference-noise-ratio. For each metric of connectivity, we also provide a simplified treatment in the case of ergodic fading channels. In each case, we assume a pair of nodes are connected if their bi-directional measure of connectivity is better than a given threshold. Our analysis relies on the central limit theorem to approximate the distribution of the combined undesired signal affecting each link of an ad-hoc network as Gaussian. Supported by our simulation results, our analysis shows that (1) a measure of connectivity purely based on signal strength is not capable of accurately capturing the connectivity phenomenon, and (2) employing multiple antenna mobile nodes improves the connectivity of fading ad-hoc networks.

Accuracy of maxillofacial prototypes fabricated by different 3-dimensional printing technologies using multi-slice and cone-beam computed tomography

Yousefi, Faezeh,Shokri, Abbas,Farhadian, Maryam,Vafaei, Fariborz,Forutan, Fereshte Korean Academy of Oral and Maxillofacial Radiology 2021 Imaging Science in Dentistry Vol.51 No.1

Purpose: This study aimed to compare the accuracy of 3-dimensional(3D) printed models derived from multidetector computed tomography (MDCT) and cone-beam computed tomography (CBCT) systems with different fields of view (FOVs). Materials and Methods: Five human dry mandibles were used to assess the accuracy of reconstructions of anatomical landmarks, bone defects, and intra-socket dimensions by 3D printers. The measurements were made on dry mandibles using a digital caliper (gold standard). The mandibles then underwent MDCT imaging. In addition, CBCT images were obtained using Cranex 3D and NewTom 3G scanners with 2 different FOVs. The images were transferred to two 3D printers, and the digital light processing (DLP) and fused deposition modeling (FDM) techniques were used to fabricate the 3D models, respectively. The same measurements were also made on the fabricated prototypes. The values measured on the 3D models were compared with the actual values, and the differences were analyzed using the paired t-test. Results: The landmarks measured on prototypes fabricated using the FDM and DLP techniques based on all 4 imaging systems showed differences from the gold standard. No significant differences were noted between the FDM and DLP techniques. Conclusion: The 3D printers were reliable systems for maxillofacial reconstruction. In this study, scanners with smaller voxels had the highest precision, and the DLP printer showed higher accuracy in reconstructing the maxillofacial landmarks. It seemed that 3D reconstructions of the anterior region were overestimated, while the reconstructions of intra-socket dimensions and implant holes were slightly underestimated.

ON THE HILBERT SPACE OF FORMAL POWER SERIES

YOUSEFI, Bahman,SOLTANI, Rahmat The Honam Mathematical Society 2004 호남수학학술지 Vol.26 No.3

Let $\{{\beta}(n)\}^{\infty}_{n=0}$ be a sequence of positive numbers such that ${\beta}(0)=1$. We consider the space $H^2({\beta})$ of all power series $f(z)=^{Po}_{n=0}{\hat{f}}(n)z^n$ such that $^{Po}_{n=0}{\mid}{\hat{f}}(n){\mid}^2{\beta}(n)^2<{\infty}$. We link the ideas of subspaces of $H^2({\beta})$ and zero sets. We give some sufficient conditions for a vector in $H^2({\beta})$ to be cyclic for the multiplication operator $M_z$. Also we characterize the commutant of some multiplication operators acting on $H^2({\beta})$.

A Green Protocol for the Bromination and Iodination of the Aromatic Compounds using H₅IO₆/NaBr and H₅IO₆/NaI in the Water

Yousefi-Seyf, Jaber,Tajeian, Kazem,Kolvari, Eskandar,Koukabi, Nadiya,Khazaei, Ardeshir,Zolfigol, Mohammad Ali Korean Chemical Society 2012 Bulletin of the Korean Chemical Society Vol.33 No.8

Bromination and iodination of the aromatic compounds have efficiently been carried out at room temperature and $70^{\circ}C$, respectively, in short reaction times using orthoperiodic acid/sodium bromide (1:2) and orthoperiodic acid/sodium iodide (1:2) in water to prepare the corresponding halo compounds with excellent yields.