AMIR HOSSEIN Mohebbi - Academia.edu (original) (raw)

Papers by AMIR HOSSEIN Mohebbi

Iranian South Medical Journal

A surprisingly large number of sea snail species are venomous. Cone snail venoms are produced in ... more A surprisingly large number of sea snail species are venomous. Cone snail venoms are produced in a lengthy tubular duct from a complex venom gland and form a cocktail of many toxins, particularly conotoxins which have high potency and specificity for their target specific receptors. They inhibit various channels, neuromuscular receptors or hormones of the victim, and interfere in the transmitted signals of the prey, or dissuade predators. Cone snails have an amazing ability to quickly convert between two different types of defense-evoked and predation-evoked venoms in response to defensive or predatory stimuli. Various conotoxins and conopeptides such as α-conotoxins, σ-conotoxins, ω-conotoxins, μ-conotoxins, ψ-conotoxins, τ-conotoxins, δ-conotoxins, κ-conotoxins and conkunitzins, conantokins, contryphans, Ac1 conotoxins, conoinsulins, granulin-like conotoxins from conoides; augerpeptides derived from the venom peptide family Terebridae; turripeptides from the venom peptide family Turridae; crassipeptides venom peptides from Crassispirids; clathurellipeptides from venomous micro-conoides Clathurellidae, and other toxins such as RFamide peptides and endogenous neuropeptide-like peptides such as conopressins, as well as contulakins have been found in cone snail venoms, which have demonstrated remarkable biological and pharmacological functions. Given the approval of some conotoxins, such as the analgesic medication ziconitide (Prialt ®) in clinical trials as well as their biomedical potential, current research has focused on these toxins. The use of integrated venomics approaches has dramatically accelerated the detection of conotoxin sequences. It is anticipated that a better understanding and identification of conotoxins and other toxins derived from other sea snails will lead to their use for the treatment of diseases to which humans have succumbed.

Iranian South Medical Journal

Background: Recent trends in the production of functional foods and nutraceutical compounds indic... more Background: Recent trends in the production of functional foods and nutraceutical compounds indicate the important role of bioactive molecules in the treatment of human diseases. In this study, some phytochemical and nutraceutical properties of Ziziphus nummularia fruit extract harvested from the Poshtpar-Dashtestan forests were evaluated. Materials and Methods: The antioxidant activity and total phenolic content of Ziziphus nummularia fruit extract were studied by 2,2-Diphenyl-1-picrylhydrazyl (DPPH), and spectrophotometric methods, respectively. The secondary metabolites were analyzed by the gas chromatography-mass spectrometry (GC-MS) method. The antimicrobial activities of the aqueous extracts against gram-positive bacteria Staphylococcus aureus and Bacillus cereus; gram-negative bacteria Escherichia coli and Salmonella typhi; mold Aspergillus niger and yeast Candida albicans were evaluated using the microdilution method. Results: The GC-MS analysis of the sample identified 51 chemical compounds with different chemical and bioactive structures, such as alkaloids, terpenes, and steroids. Furthermore, the Ziziphus extract showed significant inhibitory and lethal activities against the microbial strains, with its highest antimicrobial activity against Candida albicans. The presence of antimicrobial compounds detected by GC-MS confirmed the results of the antibacterial activity of the extract. Conclusion: According to the results, the Ziziphus nummularia extract can be an appropriate terrestrial source of antimicrobial compounds with significant performance against foodborne pathogens. Consistent with the literature, the secondary metabolites from the Ziziphus extract have potential biological and nutraceutical effects which require more laboratory studies.

Iranian South Medical Journal

Background: Brittle stars can produce well-known toxins responsible for various of their biologic... more Background: Brittle stars can produce well-known toxins responsible for various of their biological activities in addition to their physical defense. The purpose of this study was to identify secondary metabolites and assess the anticholinesterase activities of the crude venom of the Persian Gulf Ophiocoma erinaceous (brittle star) in vitro and in silico due to the abundance of this marine life on the Persian Gulf coasts and with knowledge of their numerous biological effects. Materials and Methods: In this study, after the lyophilization of the brittle star sample, an LD50 test, a test of cholinesterase inhibitory activities, identification of the secondary metabolites, and their in-silico evaluations were performed by, respectively, Spearman-Karber, the Ellman spectroscopic method, Gas Chromatography-Mass Spectrometry (GC-MS), and computational docking method. Results: According to the results, the LD50 value of the sample was 6.04±0.13 (mg/kg). The IC50 values related to their Acetylcholinesterase and Butyrylcholinesterase were 37.925 ±0.055 and 5.388±0.02 (μg/ml), respectively, compared to the galantamine standard. The GC-MS analysis of the sample showed 25 bioactive chemical compositions with different structures, such as alkaloids, terpenes, and steroids. The computational results of the compounds also confirmed the experimental results. Among these, the alkaloidal compound BS4, had the highest affinity for both enzymes. Conclusion: As for toxicity potency, the brittle star crude venom sample was classified in the highly toxic category. The GC analysis of the crude venom showed various bioactive secondary metabolites with different chemical structures. The experimental and computational results on the anticholinesterase activities of the sample showed that the venom acts as a significant inhibitor of both enzymes. Further studies are required to determine whether the compound BS4 could be a candidate for the treatment of Alzheimer's disease.

International Journal of Surgery Case Reports

Iranian Journal of Chemistry & Chemical Engineering-international English Edition, Dec 1, 2004

Microwave irradiation is used in the synthesis of four tricyclic chromanones 11-14. The chromanon... more Microwave irradiation is used in the synthesis of four tricyclic chromanones 11-14. The chromanone 14 and 12 are selectively formed thermally and under microwave in the presence of polyphosphoric acid (PPA) from the same dicarboxylic acid 9, respectively. The crystal structures of the two diacids are also reported. The corresponding ortho and meta isomers of diacids crystallize in the space group Pbca of the orthorhombic system and C 2 /c of the monoclinic

The Arakawa-Kaneko zeta function has been introduced ten years ago by T. Arakawa and M. Kaneko in... more The Arakawa-Kaneko zeta function has been introduced ten years ago by T. Arakawa and M. Kaneko in [22]. In [22], Arakawa and Kaneko have expressed the special values of this function at negative integers with the help of generalized Bernoulli numbers B(k) called poly-Bernoulli numbers. Kim-Kim [4] introduced Multi poly- Bernoulli numbers and proved that special values of certain zeta functions at non-positive integers can be<br> described in terms of these numbers.

Muṭāli̒āt-i Mudīriyyat-i Ṣan̒atī, 2019

Nowadays, most supply chains are starting to go green in their business with pay more attention t... more Nowadays, most supply chains are starting to go green in their business with pay more attention to environmental protection as competitive advantage. Therefore, Designing a two-stage green supply chain for optimum assignment a green supplier to a green producer based on maximum efficiency and attention to intermediate products and processes is essential. Because, economic performance and environmental performance of the supply chain will increases. One of the methods used to evaluating efficiency in the green supply chain management, is data envelopment analysis (DEA). The traditional DEA methods for evaluating efficiency of supply chain processes and multi-stage systems not working properly, Because, each decision making units is assumed as a black box and ignore its internal processes. In order to overcome this deficiency, a novel two-stage network DEA will be presented based on the concepts of Electrical Engineering that ability to consider all inputs, Intermediate products, desi...

Shortest-path problem is one of the well-known optimization problems that has been studied by man... more Shortest-path problem is one of the well-known optimization problems that has been studied by many scientists in recent years. Applications of this problem such as transportation and communication are generally solved by Dijkstra's Algorithm (Labeling). In this paper, two separate scientific fields, electronics and operation research have been linked to each other and a new algorithm has been created for to find the optimization solution of a shortest- path problem by using electric networks and rules. The proposed algorithm can solve the shortest-path problem in directed graphs and no order ones, and also can solve the longest path problems in directed graphs. In this algorithm, electrical network are used in a way that the resistance value of each branch is equal to each edge weights in the shortest-path problems. Then with using Ohm Law and Kirchhaffs Voltage Law (KVL), the current in each circuit cycle is calculated. Then the branches that contain the most passing current are specified, and according to Ohm's Law, has the lowest resistance or weight. Thus, the shortest path in the network is achieved. Advantage of this algorithm is faster convergence to the answer and less computing time than the conventional method, especially in networks with more nods. The mentioned algorithm has been described for three examples.

Acta medica Iranica, 2015

This study was conducted to evaluate the association between H. pylori infection and Iron deficie... more This study was conducted to evaluate the association between H. pylori infection and Iron deficiency anemia (IDA) among preschool children (age range: 40-75 months) at a tertiary referral hospital in Tehran.In a case-control study, the prevalence of H. pylori seropositivity was compared between 64 children with IDA diagnosis and 70 healthy non-anemic sex- and age-matched controls. Totally, 52 (81.3%) children with IDA and 10 (14.3%) non-anemic controls had a positive antibody level for H. pylori specific IgG and the difference between two groups was statistically significant (P<0.0001). H. pylori infection had a significant high prevalence among preschool patients with IDA. Eradication of H. pylori infection is recommended for patients with refractory IDA.

Computational Methods for Differential Equations, 2018

A mathematical model of a within-host viral infection is presented. A local stability analysis of... more A mathematical model of a within-host viral infection is presented. A local stability analysis of the model is conducted in two ways. At first, the basic reproduction number of the system is calculated. It is shown that when the reproduction number falls below unity, the disease free equilibrium (DFE) is globally asymptotically stable, and when it exceeds unity, the DFE is unstable and there exists a unique infectious equilibrium which may or may not be stable. In the case of instability, there exists an asymptotically stable periodic solution. Secondly, an analysis of local center manifold shows that when R0 = 1, a transcritical bifurcation occurs where upon increasing R0 greater than one the DFE loses stability and a locally asymptotically positive infection equilibrium appears.

Objective The current COVID-19 pandemic impose many challenges including maintain educational pro... more Objective The current COVID-19 pandemic impose many challenges including maintain educational programs delivery obstacles. The aim of this study was to investigate orthopedics residents’ opinion towards using online methods to sustain medical education. Methods A cross sectional study applying an 8-item questionnaire was performed to investigate 150 Iranian residents’ attitudes towards online medical learning programs. Results One-hundred thirty two residents (88%) replied back the questionnaire. 89% of the participants reported they use online methods; most frequent method was online webinars by 84%. They frequently used Skyroom (76%) to take part in the educational events. Satisfaction rate for webinar was reported as well as 8.2. Weak internet connection and speed was the main problem reported by the participants. 91.8% of the residents supposed continuing the online education would be useful. Conclusion Orthopedic residents believed that Online educating programs would be favora...

Tunicates are a large group of marine animals; and have been named "tunicate" because of cellosic... more Tunicates are a large group of marine animals; and have been named "tunicate" because of cellosic outer covering called a tunic. They are divided into four major classes of the ascidians, thaliaceans, appendicularians and Sorberacea. Ascidians are the most diverse tunicate group. They are a rich source of secondary metabolites. Alkaloids are the major class of this compounds that mostly, display biological activity. Pyridoacridine alkaloids have a significant biological activities and their main mechanism is DNA cleavage inhibition by reactive oxygen species (ROS). The pyrroloacridine alkaloids are mostly cytotoxic; and also, indole alkaloids have numerous biological properties such as potent antiviral, antiinflammatory and cytotoxicity activities. Pyrrole Alkaloids exhibited several biological properties, like strong calmodulin antagonistic, antileukemic, inhibiting Na + /K + ATPase, activating the octomyosin ATPase, and inducing release of Ca 2+ from sarcoplasmic reticulum. Tunicates are a rich source of peptides, cyclic oligopeptides and depsipeptides such as patellamides, Didemnin, Iodocionin, Apliamides, Halocidin, Dicynthaurin or Clavanin, with significant biological activities. Some compounds extracted from tunicates such as, Glabruquionones, prenylhydroquinone, geranylhydroquinone, Longithorone, scabellones, and conithiaquinones have different structures of linear or cyclic hydroquinone and quinones. They possess a wide range of biological activities as strong anti-tumor, anti-leukemia, anti-oxidant, antiviral, and selective cytotoxicity properties. Other numerous compounds with unique structures and different biological activities such as Phallusiasterols with modulating the PXR receptor; Lepadins with antiplasmodial and antitrypanosomal properties; Coproverdine with cytotoxic and anti-tumor activity; and Ningalin with a strong inhibitory effects on CK1δ, CDK5 and GSK3β kinase, have been extracted from these animals. A large diversity of biological active compoundes from marine tunicates explains this realty that they have a large capacity to search and devalopement new marine medicinal compounds. It is hoped that in the future, marine drugs, have a greater portion in the drugstore shelves.

Quarterly Journal of Nursing Management, 2020

Introduction: It has been shown that the mental wellbeing of nurses could positively influence th... more Introduction: It has been shown that the mental wellbeing of nurses could positively influence their work engagement and quality of care. Therefore, the present study want to examine the effect of managers’ computational behaviors, as an example of social support, on the nurses’ work engagement and psychological distress. Methods: This study is a descriptive-correlational survey was conducted in 2017 based on the structural modeling. The study population was 72 nurses of intensive care unit in Afshar Hospital of Yazd, Iran. The data were collected using four standard questionnaires and analyzed using both descriptive and inferential statistics by SPSS16 and LISREL8.8. Results: The results showed that positive communicational behaviors of the supervisors and managers could significantly enhance the nurses' work engagement (P<0.05). Moreover, we found that the psychological distress of the nurses significantly decreased by positive communicational behaviors of their supervisors...

Iranian Journal of Child Neurology, 2020

Objective One of the difficulties to conduct electroencephalography (EEG) in pediatric patient po... more Objective One of the difficulties to conduct electroencephalography (EEG) in pediatric patient population is that they are not always cooperative during the procedure. Different medications are used to induce sedation during EEG recording. In order to find a medication with the least adverse effects and high efficacy, the current study aimed at comparing clonidine and chloral hydrate as a premedication prior to EEG recording in pediatric population. Materials & Methods A prospective, randomized, single-blinded, controlled trial was conducted on 198 children (9 to 156 months old) to investigate the sedative and adverse effects of clonidine and chloral hydrate. Patients, partially sleep-deprived the night before, were randomly divided into two groups of clonidine (n=100) and chloral hydrate (n=98) on an alternative day basis. Results The average sleep onset latency was significantly longer in the clonidine group than chloral hydrate group (the Mann-Whitney test, p <0.0001). Sleep d...

Cancer Management and Research, 2019

Immune checkpoint inhibitors (ICI) as monotherapy in selected patients as well as in combination ... more Immune checkpoint inhibitors (ICI) as monotherapy in selected patients as well as in combination with chemotherapy have become the standard of care in the first-line treatment strategy of advanced non-small cell lung cancer (NSCLC) patients. Combination treatment with ICI, such as nivolumab and ipilimumab or durvaluamb and ipilimumab, has also been proposed as potential strategies in this setting in selected advanced NSCLC patients. Characterizing predictive markers of long-term clinical benefit with ICI is a critical objective. Tumor mutational burden has been proposed as a potential predictive biomarker. In this review, we discuss the efficacy of nivolumab and ipilimumab in advanced NSCLC patients as well as the clinical utility of tumor mutational burden in the efficacy of this combination. Ongoing clinical trials with nivolumab and ipilimumab, and the efficacy of this combination in subgroups of NSCLC patients, such as elderly patients and patients with brain metastases, are also discussed.

Discrete & Continuous Dynamical Systems - B, 2018

In this paper, we introduce and analyze a mathematical model of a viral infection with explicit a... more In this paper, we introduce and analyze a mathematical model of a viral infection with explicit age-since infection structure for infected cells. We extend previous age-structured within-host virus models by including logistic growth of target cells and allowing for absorption of multiple virus particles by infected cells. The persistence of the virus is shown to depend on the basic reproduction number R 0. In particular, when R 0 ≤ 1, the infection free equilibrium is globally asymptotically stable, and conversely if R 0 > 1, then the infection free equilibrium is unstable, the system is uniformly persistent and there exists a unique positive equilibrium. We show that our system undergoes a Hopf bifurcation through which the infection equilibrium loses the stability and periodic solutions appear.

The Egyptian Journal of Aquatic Research, 2017

The upside-down jellyfish produces venom with some biological activities. In the present study, d... more The upside-down jellyfish produces venom with some biological activities. In the present study, direct cardiotoxicity of crude tentacle-only extract from the Persian Gulf jellyfish ''Cassiopea sp." was assessed by a Langendorff isolated perfused rat heart system. Treatments were performed with concentrations of 50, 20, 10, 5, and 2.5 lg/ml of crude tentacle-only extract (CTOE) on isolated rat hearts for 60 min. Then, the hemodynamic parameters of heart rate, left ventricular end-diastolic pressure, left ventricular systolic pressure, left ventricular developed pressure, and coronary flow were evaluated. Lactate dehydrogenase (LDH) levels as well as histopathological examinations were also investigated. Based on the ECG findings, treatments in a dose-dependent pattern changed cardiac electrical activity and decreased coronary effluent. The higher concentrations of CTOE produced severe bradycardia, atrioventricular dissociation, complete atrioventricular block, and ultimately cardiac arrest. Ventricular end-diastolic pressure was also significantly increased by high concentrations of CTOE. At high CTOE concentrations, scatter lymphocytic infiltration and wavy fibers were found in the histopathological examinations. Treatment with concentrations of 2.5-10 lg/ml caused a considerable increase in LDH levels within 30 min compared with baseline levels. In conclusion, CTOE from the Persian Gulf upside-down jellyfish had significant direct cardiotoxicity effects on isolated rat hearts.

Background: Marine neurotoxins as of Marine biotoxins are natural toxins that produced mainly by ... more Background: Marine neurotoxins as of Marine biotoxins are natural toxins that produced mainly by dinoflagellates, diatoms and several species of invertebrates and fish. Marine poisoning results from the ingestion of marine animals contain these toxins and causes considerable adverse effects. Materials and methods: This review provides some facts about the structures of marine neurotoxins, their molecular target and pharmacology, analytical methods for their detection and quantitation, diagnosis and laboratory testing, clinical manifestations, as well as prevention and treatment, if were obtainable. Furthermore, we focus on marine poisoning and various associated neurological syndromes like ciguatera, tetrodotoxin poisoning, and paralytic shellfish poisoning, after ingestion of the common marine toxins. Results: A number of neurotoxins that prescribed according to their potency (LD 50) are: Maitotoxin, Ciguatoxins and Palytoxin, Tetrodotoxin and Saxitoxin, Brevetoxins, Azaspiracid, Yessotoxin, Cooliatoxin, Domoic acid and Conotoxins, Respectively. The primary target of most marine neurotoxins is voltage gated sodium channels and the resulting block of ion conductance through these channels. Moreover, these compounds interact with voltage-gated potassium and calcium channels and modulate the flux of stated ions into many cell types. As well, the target recognized for palytoxin is the Na +-K + /ATPase. Conclusion: Results of reviewed studies revealed that, the Ciguatera is the commonest syndrome of marine poisoning, but is rarely lethal. Puffer fish poisoning results from the ingestion of fish containing tetrodotoxin and paralytic shellfish poisoning are less common, but have a higher fatality rate than ciguatera. Despite their high toxicity, no much research has been done on some of the toxins, like maitotoxin. In addition, there have remained unknown the pharmacological effects, mechanism of action and molecular target of some toxins such as Cooliatoxin and Ostreotoxins, Which could be the subject of the research in Future, or perhaps a new generation of drugs.

Background: The Persian Gulf is one of the best places to find tropical venomous animals. The sec... more Background: The Persian Gulf is one of the best places to find tropical venomous animals. The second cause of marine injuries in the Persian Gulf region is stonefish, it seems that the medical practitioners in this region are not familiar with the medical management of stonefish envenomationon. Materials and methods: A total of 16 patients with stonefish envenomation were serially examined in emergency rooms of academic hospitals of Boushehr port and Delvar clinic. In these patients local and systemic manifestations, first aid management and therapeutic interventions were evaluated. Results: The most common sites of injury were lower extremity (14 cases) and upper extremities (2 cases). The most common prescribing medication for relief of pain was injection of local lidocaine. The second and third most common prescribed drugs were parenteral antihistamines and corticosteroids, respectively. Hot water was not used in any of patients. Only in 2 cases antibiotic were given, whereas tetabolin was not prescribed in any of them. Conclusion: Although the most effective pain relieving intervention for stonefish envenomation, it was not used in injured patients in the current study. Likewise, tetabolin was not used. The medical practitioners should be encouraged to use immersion of the injured site in hot water, injection of local lidocaine without adrenalin, tetabolin injection and prophylactic broad spectrum antibiotics in stonefish envenomation.

British Food Journal, 2013

Purpose-The purpose of this paper is to determine the peroxide value (PV), p-anisidine and total ... more Purpose-The purpose of this paper is to determine the peroxide value (PV), p-anisidine and total oxidation value (TOTOX) values of imported edible oils in Iran. Design/methodology/approach-A total 196 oil samples of different origin and types (corn, olive, canola and grape-seed oil) were collected randomly from Boushehr port of Iran and a total 27 oil samples were also collected from frying pans used to deep-fry local food items at different restaurants in Boushehr city. Findings-The PVs ranged from 1.38-13.74, 3.90-20.00, 0.83-2.99, 0.67-11.95 and 0.00-9.96 mequiv/kg found in refined olive oil, virgin olive oil, canola oil, grape-seed oil and corn oil, respectively. The results showed that PVs of 18.37 percent of imported oil and 62.96 percent of frying oils from restaurant exceeded the maximum acceptable limits set by Institute of Standards and Industrial Research of Iran (ISIRI) (2-20 mequiv/kg for different types of oils). P-anisidine value ranged from 0.89-27.56 mequiv/kg in imported oils and 2.21-30.76 mequiv/kg found in frying oil from restaurants. The TOTOX value increased linearly with peroxide values and p-anisidine values. It ranged from 0.89-76.62. Originality/value-Fried foods are very common in Iranians' diet. A major portion of the edible oils in Iran are imported from other countries through Boushehr port. ISIRI has set maximum acceptable limit for PVs in different oils imported to the country. The possible effects of storage on oil oxidation are the original criteria of this research. The results of the study indicate that inappropriate storage of edible oils and their use in frying applications at restaurants facilitate oil oxidation and deterioration.

Iranian South Medical Journal

A surprisingly large number of sea snail species are venomous. Cone snail venoms are produced in ... more A surprisingly large number of sea snail species are venomous. Cone snail venoms are produced in a lengthy tubular duct from a complex venom gland and form a cocktail of many toxins, particularly conotoxins which have high potency and specificity for their target specific receptors. They inhibit various channels, neuromuscular receptors or hormones of the victim, and interfere in the transmitted signals of the prey, or dissuade predators. Cone snails have an amazing ability to quickly convert between two different types of defense-evoked and predation-evoked venoms in response to defensive or predatory stimuli. Various conotoxins and conopeptides such as α-conotoxins, σ-conotoxins, ω-conotoxins, μ-conotoxins, ψ-conotoxins, τ-conotoxins, δ-conotoxins, κ-conotoxins and conkunitzins, conantokins, contryphans, Ac1 conotoxins, conoinsulins, granulin-like conotoxins from conoides; augerpeptides derived from the venom peptide family Terebridae; turripeptides from the venom peptide family Turridae; crassipeptides venom peptides from Crassispirids; clathurellipeptides from venomous micro-conoides Clathurellidae, and other toxins such as RFamide peptides and endogenous neuropeptide-like peptides such as conopressins, as well as contulakins have been found in cone snail venoms, which have demonstrated remarkable biological and pharmacological functions. Given the approval of some conotoxins, such as the analgesic medication ziconitide (Prialt ®) in clinical trials as well as their biomedical potential, current research has focused on these toxins. The use of integrated venomics approaches has dramatically accelerated the detection of conotoxin sequences. It is anticipated that a better understanding and identification of conotoxins and other toxins derived from other sea snails will lead to their use for the treatment of diseases to which humans have succumbed.

Iranian South Medical Journal

Background: Recent trends in the production of functional foods and nutraceutical compounds indic... more Background: Recent trends in the production of functional foods and nutraceutical compounds indicate the important role of bioactive molecules in the treatment of human diseases. In this study, some phytochemical and nutraceutical properties of Ziziphus nummularia fruit extract harvested from the Poshtpar-Dashtestan forests were evaluated. Materials and Methods: The antioxidant activity and total phenolic content of Ziziphus nummularia fruit extract were studied by 2,2-Diphenyl-1-picrylhydrazyl (DPPH), and spectrophotometric methods, respectively. The secondary metabolites were analyzed by the gas chromatography-mass spectrometry (GC-MS) method. The antimicrobial activities of the aqueous extracts against gram-positive bacteria Staphylococcus aureus and Bacillus cereus; gram-negative bacteria Escherichia coli and Salmonella typhi; mold Aspergillus niger and yeast Candida albicans were evaluated using the microdilution method. Results: The GC-MS analysis of the sample identified 51 chemical compounds with different chemical and bioactive structures, such as alkaloids, terpenes, and steroids. Furthermore, the Ziziphus extract showed significant inhibitory and lethal activities against the microbial strains, with its highest antimicrobial activity against Candida albicans. The presence of antimicrobial compounds detected by GC-MS confirmed the results of the antibacterial activity of the extract. Conclusion: According to the results, the Ziziphus nummularia extract can be an appropriate terrestrial source of antimicrobial compounds with significant performance against foodborne pathogens. Consistent with the literature, the secondary metabolites from the Ziziphus extract have potential biological and nutraceutical effects which require more laboratory studies.

Iranian South Medical Journal

Background: Brittle stars can produce well-known toxins responsible for various of their biologic... more Background: Brittle stars can produce well-known toxins responsible for various of their biological activities in addition to their physical defense. The purpose of this study was to identify secondary metabolites and assess the anticholinesterase activities of the crude venom of the Persian Gulf Ophiocoma erinaceous (brittle star) in vitro and in silico due to the abundance of this marine life on the Persian Gulf coasts and with knowledge of their numerous biological effects. Materials and Methods: In this study, after the lyophilization of the brittle star sample, an LD50 test, a test of cholinesterase inhibitory activities, identification of the secondary metabolites, and their in-silico evaluations were performed by, respectively, Spearman-Karber, the Ellman spectroscopic method, Gas Chromatography-Mass Spectrometry (GC-MS), and computational docking method. Results: According to the results, the LD50 value of the sample was 6.04±0.13 (mg/kg). The IC50 values related to their Acetylcholinesterase and Butyrylcholinesterase were 37.925 ±0.055 and 5.388±0.02 (μg/ml), respectively, compared to the galantamine standard. The GC-MS analysis of the sample showed 25 bioactive chemical compositions with different structures, such as alkaloids, terpenes, and steroids. The computational results of the compounds also confirmed the experimental results. Among these, the alkaloidal compound BS4, had the highest affinity for both enzymes. Conclusion: As for toxicity potency, the brittle star crude venom sample was classified in the highly toxic category. The GC analysis of the crude venom showed various bioactive secondary metabolites with different chemical structures. The experimental and computational results on the anticholinesterase activities of the sample showed that the venom acts as a significant inhibitor of both enzymes. Further studies are required to determine whether the compound BS4 could be a candidate for the treatment of Alzheimer's disease.

International Journal of Surgery Case Reports

Iranian Journal of Chemistry & Chemical Engineering-international English Edition, Dec 1, 2004

Microwave irradiation is used in the synthesis of four tricyclic chromanones 11-14. The chromanon... more Microwave irradiation is used in the synthesis of four tricyclic chromanones 11-14. The chromanone 14 and 12 are selectively formed thermally and under microwave in the presence of polyphosphoric acid (PPA) from the same dicarboxylic acid 9, respectively. The crystal structures of the two diacids are also reported. The corresponding ortho and meta isomers of diacids crystallize in the space group Pbca of the orthorhombic system and C 2 /c of the monoclinic

The Arakawa-Kaneko zeta function has been introduced ten years ago by T. Arakawa and M. Kaneko in... more The Arakawa-Kaneko zeta function has been introduced ten years ago by T. Arakawa and M. Kaneko in [22]. In [22], Arakawa and Kaneko have expressed the special values of this function at negative integers with the help of generalized Bernoulli numbers B(k) called poly-Bernoulli numbers. Kim-Kim [4] introduced Multi poly- Bernoulli numbers and proved that special values of certain zeta functions at non-positive integers can be<br> described in terms of these numbers.

Muṭāli̒āt-i Mudīriyyat-i Ṣan̒atī, 2019

Nowadays, most supply chains are starting to go green in their business with pay more attention t... more Nowadays, most supply chains are starting to go green in their business with pay more attention to environmental protection as competitive advantage. Therefore, Designing a two-stage green supply chain for optimum assignment a green supplier to a green producer based on maximum efficiency and attention to intermediate products and processes is essential. Because, economic performance and environmental performance of the supply chain will increases. One of the methods used to evaluating efficiency in the green supply chain management, is data envelopment analysis (DEA). The traditional DEA methods for evaluating efficiency of supply chain processes and multi-stage systems not working properly, Because, each decision making units is assumed as a black box and ignore its internal processes. In order to overcome this deficiency, a novel two-stage network DEA will be presented based on the concepts of Electrical Engineering that ability to consider all inputs, Intermediate products, desi...

Shortest-path problem is one of the well-known optimization problems that has been studied by man... more Shortest-path problem is one of the well-known optimization problems that has been studied by many scientists in recent years. Applications of this problem such as transportation and communication are generally solved by Dijkstra's Algorithm (Labeling). In this paper, two separate scientific fields, electronics and operation research have been linked to each other and a new algorithm has been created for to find the optimization solution of a shortest- path problem by using electric networks and rules. The proposed algorithm can solve the shortest-path problem in directed graphs and no order ones, and also can solve the longest path problems in directed graphs. In this algorithm, electrical network are used in a way that the resistance value of each branch is equal to each edge weights in the shortest-path problems. Then with using Ohm Law and Kirchhaffs Voltage Law (KVL), the current in each circuit cycle is calculated. Then the branches that contain the most passing current are specified, and according to Ohm's Law, has the lowest resistance or weight. Thus, the shortest path in the network is achieved. Advantage of this algorithm is faster convergence to the answer and less computing time than the conventional method, especially in networks with more nods. The mentioned algorithm has been described for three examples.

Acta medica Iranica, 2015

This study was conducted to evaluate the association between H. pylori infection and Iron deficie... more This study was conducted to evaluate the association between H. pylori infection and Iron deficiency anemia (IDA) among preschool children (age range: 40-75 months) at a tertiary referral hospital in Tehran.In a case-control study, the prevalence of H. pylori seropositivity was compared between 64 children with IDA diagnosis and 70 healthy non-anemic sex- and age-matched controls. Totally, 52 (81.3%) children with IDA and 10 (14.3%) non-anemic controls had a positive antibody level for H. pylori specific IgG and the difference between two groups was statistically significant (P<0.0001). H. pylori infection had a significant high prevalence among preschool patients with IDA. Eradication of H. pylori infection is recommended for patients with refractory IDA.

Computational Methods for Differential Equations, 2018

A mathematical model of a within-host viral infection is presented. A local stability analysis of... more A mathematical model of a within-host viral infection is presented. A local stability analysis of the model is conducted in two ways. At first, the basic reproduction number of the system is calculated. It is shown that when the reproduction number falls below unity, the disease free equilibrium (DFE) is globally asymptotically stable, and when it exceeds unity, the DFE is unstable and there exists a unique infectious equilibrium which may or may not be stable. In the case of instability, there exists an asymptotically stable periodic solution. Secondly, an analysis of local center manifold shows that when R0 = 1, a transcritical bifurcation occurs where upon increasing R0 greater than one the DFE loses stability and a locally asymptotically positive infection equilibrium appears.

Objective The current COVID-19 pandemic impose many challenges including maintain educational pro... more Objective The current COVID-19 pandemic impose many challenges including maintain educational programs delivery obstacles. The aim of this study was to investigate orthopedics residents’ opinion towards using online methods to sustain medical education. Methods A cross sectional study applying an 8-item questionnaire was performed to investigate 150 Iranian residents’ attitudes towards online medical learning programs. Results One-hundred thirty two residents (88%) replied back the questionnaire. 89% of the participants reported they use online methods; most frequent method was online webinars by 84%. They frequently used Skyroom (76%) to take part in the educational events. Satisfaction rate for webinar was reported as well as 8.2. Weak internet connection and speed was the main problem reported by the participants. 91.8% of the residents supposed continuing the online education would be useful. Conclusion Orthopedic residents believed that Online educating programs would be favora...

Tunicates are a large group of marine animals; and have been named "tunicate" because of cellosic... more Tunicates are a large group of marine animals; and have been named "tunicate" because of cellosic outer covering called a tunic. They are divided into four major classes of the ascidians, thaliaceans, appendicularians and Sorberacea. Ascidians are the most diverse tunicate group. They are a rich source of secondary metabolites. Alkaloids are the major class of this compounds that mostly, display biological activity. Pyridoacridine alkaloids have a significant biological activities and their main mechanism is DNA cleavage inhibition by reactive oxygen species (ROS). The pyrroloacridine alkaloids are mostly cytotoxic; and also, indole alkaloids have numerous biological properties such as potent antiviral, antiinflammatory and cytotoxicity activities. Pyrrole Alkaloids exhibited several biological properties, like strong calmodulin antagonistic, antileukemic, inhibiting Na + /K + ATPase, activating the octomyosin ATPase, and inducing release of Ca 2+ from sarcoplasmic reticulum. Tunicates are a rich source of peptides, cyclic oligopeptides and depsipeptides such as patellamides, Didemnin, Iodocionin, Apliamides, Halocidin, Dicynthaurin or Clavanin, with significant biological activities. Some compounds extracted from tunicates such as, Glabruquionones, prenylhydroquinone, geranylhydroquinone, Longithorone, scabellones, and conithiaquinones have different structures of linear or cyclic hydroquinone and quinones. They possess a wide range of biological activities as strong anti-tumor, anti-leukemia, anti-oxidant, antiviral, and selective cytotoxicity properties. Other numerous compounds with unique structures and different biological activities such as Phallusiasterols with modulating the PXR receptor; Lepadins with antiplasmodial and antitrypanosomal properties; Coproverdine with cytotoxic and anti-tumor activity; and Ningalin with a strong inhibitory effects on CK1δ, CDK5 and GSK3β kinase, have been extracted from these animals. A large diversity of biological active compoundes from marine tunicates explains this realty that they have a large capacity to search and devalopement new marine medicinal compounds. It is hoped that in the future, marine drugs, have a greater portion in the drugstore shelves.

Quarterly Journal of Nursing Management, 2020

Introduction: It has been shown that the mental wellbeing of nurses could positively influence th... more Introduction: It has been shown that the mental wellbeing of nurses could positively influence their work engagement and quality of care. Therefore, the present study want to examine the effect of managers’ computational behaviors, as an example of social support, on the nurses’ work engagement and psychological distress. Methods: This study is a descriptive-correlational survey was conducted in 2017 based on the structural modeling. The study population was 72 nurses of intensive care unit in Afshar Hospital of Yazd, Iran. The data were collected using four standard questionnaires and analyzed using both descriptive and inferential statistics by SPSS16 and LISREL8.8. Results: The results showed that positive communicational behaviors of the supervisors and managers could significantly enhance the nurses' work engagement (P<0.05). Moreover, we found that the psychological distress of the nurses significantly decreased by positive communicational behaviors of their supervisors...

Iranian Journal of Child Neurology, 2020

Objective One of the difficulties to conduct electroencephalography (EEG) in pediatric patient po... more Objective One of the difficulties to conduct electroencephalography (EEG) in pediatric patient population is that they are not always cooperative during the procedure. Different medications are used to induce sedation during EEG recording. In order to find a medication with the least adverse effects and high efficacy, the current study aimed at comparing clonidine and chloral hydrate as a premedication prior to EEG recording in pediatric population. Materials & Methods A prospective, randomized, single-blinded, controlled trial was conducted on 198 children (9 to 156 months old) to investigate the sedative and adverse effects of clonidine and chloral hydrate. Patients, partially sleep-deprived the night before, were randomly divided into two groups of clonidine (n=100) and chloral hydrate (n=98) on an alternative day basis. Results The average sleep onset latency was significantly longer in the clonidine group than chloral hydrate group (the Mann-Whitney test, p <0.0001). Sleep d...

Cancer Management and Research, 2019

Immune checkpoint inhibitors (ICI) as monotherapy in selected patients as well as in combination ... more Immune checkpoint inhibitors (ICI) as monotherapy in selected patients as well as in combination with chemotherapy have become the standard of care in the first-line treatment strategy of advanced non-small cell lung cancer (NSCLC) patients. Combination treatment with ICI, such as nivolumab and ipilimumab or durvaluamb and ipilimumab, has also been proposed as potential strategies in this setting in selected advanced NSCLC patients. Characterizing predictive markers of long-term clinical benefit with ICI is a critical objective. Tumor mutational burden has been proposed as a potential predictive biomarker. In this review, we discuss the efficacy of nivolumab and ipilimumab in advanced NSCLC patients as well as the clinical utility of tumor mutational burden in the efficacy of this combination. Ongoing clinical trials with nivolumab and ipilimumab, and the efficacy of this combination in subgroups of NSCLC patients, such as elderly patients and patients with brain metastases, are also discussed.

Discrete & Continuous Dynamical Systems - B, 2018

In this paper, we introduce and analyze a mathematical model of a viral infection with explicit a... more In this paper, we introduce and analyze a mathematical model of a viral infection with explicit age-since infection structure for infected cells. We extend previous age-structured within-host virus models by including logistic growth of target cells and allowing for absorption of multiple virus particles by infected cells. The persistence of the virus is shown to depend on the basic reproduction number R 0. In particular, when R 0 ≤ 1, the infection free equilibrium is globally asymptotically stable, and conversely if R 0 > 1, then the infection free equilibrium is unstable, the system is uniformly persistent and there exists a unique positive equilibrium. We show that our system undergoes a Hopf bifurcation through which the infection equilibrium loses the stability and periodic solutions appear.

The Egyptian Journal of Aquatic Research, 2017

The upside-down jellyfish produces venom with some biological activities. In the present study, d... more The upside-down jellyfish produces venom with some biological activities. In the present study, direct cardiotoxicity of crude tentacle-only extract from the Persian Gulf jellyfish ''Cassiopea sp." was assessed by a Langendorff isolated perfused rat heart system. Treatments were performed with concentrations of 50, 20, 10, 5, and 2.5 lg/ml of crude tentacle-only extract (CTOE) on isolated rat hearts for 60 min. Then, the hemodynamic parameters of heart rate, left ventricular end-diastolic pressure, left ventricular systolic pressure, left ventricular developed pressure, and coronary flow were evaluated. Lactate dehydrogenase (LDH) levels as well as histopathological examinations were also investigated. Based on the ECG findings, treatments in a dose-dependent pattern changed cardiac electrical activity and decreased coronary effluent. The higher concentrations of CTOE produced severe bradycardia, atrioventricular dissociation, complete atrioventricular block, and ultimately cardiac arrest. Ventricular end-diastolic pressure was also significantly increased by high concentrations of CTOE. At high CTOE concentrations, scatter lymphocytic infiltration and wavy fibers were found in the histopathological examinations. Treatment with concentrations of 2.5-10 lg/ml caused a considerable increase in LDH levels within 30 min compared with baseline levels. In conclusion, CTOE from the Persian Gulf upside-down jellyfish had significant direct cardiotoxicity effects on isolated rat hearts.

Background: Marine neurotoxins as of Marine biotoxins are natural toxins that produced mainly by ... more Background: Marine neurotoxins as of Marine biotoxins are natural toxins that produced mainly by dinoflagellates, diatoms and several species of invertebrates and fish. Marine poisoning results from the ingestion of marine animals contain these toxins and causes considerable adverse effects. Materials and methods: This review provides some facts about the structures of marine neurotoxins, their molecular target and pharmacology, analytical methods for their detection and quantitation, diagnosis and laboratory testing, clinical manifestations, as well as prevention and treatment, if were obtainable. Furthermore, we focus on marine poisoning and various associated neurological syndromes like ciguatera, tetrodotoxin poisoning, and paralytic shellfish poisoning, after ingestion of the common marine toxins. Results: A number of neurotoxins that prescribed according to their potency (LD 50) are: Maitotoxin, Ciguatoxins and Palytoxin, Tetrodotoxin and Saxitoxin, Brevetoxins, Azaspiracid, Yessotoxin, Cooliatoxin, Domoic acid and Conotoxins, Respectively. The primary target of most marine neurotoxins is voltage gated sodium channels and the resulting block of ion conductance through these channels. Moreover, these compounds interact with voltage-gated potassium and calcium channels and modulate the flux of stated ions into many cell types. As well, the target recognized for palytoxin is the Na +-K + /ATPase. Conclusion: Results of reviewed studies revealed that, the Ciguatera is the commonest syndrome of marine poisoning, but is rarely lethal. Puffer fish poisoning results from the ingestion of fish containing tetrodotoxin and paralytic shellfish poisoning are less common, but have a higher fatality rate than ciguatera. Despite their high toxicity, no much research has been done on some of the toxins, like maitotoxin. In addition, there have remained unknown the pharmacological effects, mechanism of action and molecular target of some toxins such as Cooliatoxin and Ostreotoxins, Which could be the subject of the research in Future, or perhaps a new generation of drugs.

Background: The Persian Gulf is one of the best places to find tropical venomous animals. The sec... more Background: The Persian Gulf is one of the best places to find tropical venomous animals. The second cause of marine injuries in the Persian Gulf region is stonefish, it seems that the medical practitioners in this region are not familiar with the medical management of stonefish envenomationon. Materials and methods: A total of 16 patients with stonefish envenomation were serially examined in emergency rooms of academic hospitals of Boushehr port and Delvar clinic. In these patients local and systemic manifestations, first aid management and therapeutic interventions were evaluated. Results: The most common sites of injury were lower extremity (14 cases) and upper extremities (2 cases). The most common prescribing medication for relief of pain was injection of local lidocaine. The second and third most common prescribed drugs were parenteral antihistamines and corticosteroids, respectively. Hot water was not used in any of patients. Only in 2 cases antibiotic were given, whereas tetabolin was not prescribed in any of them. Conclusion: Although the most effective pain relieving intervention for stonefish envenomation, it was not used in injured patients in the current study. Likewise, tetabolin was not used. The medical practitioners should be encouraged to use immersion of the injured site in hot water, injection of local lidocaine without adrenalin, tetabolin injection and prophylactic broad spectrum antibiotics in stonefish envenomation.

British Food Journal, 2013

Purpose-The purpose of this paper is to determine the peroxide value (PV), p-anisidine and total ... more Purpose-The purpose of this paper is to determine the peroxide value (PV), p-anisidine and total oxidation value (TOTOX) values of imported edible oils in Iran. Design/methodology/approach-A total 196 oil samples of different origin and types (corn, olive, canola and grape-seed oil) were collected randomly from Boushehr port of Iran and a total 27 oil samples were also collected from frying pans used to deep-fry local food items at different restaurants in Boushehr city. Findings-The PVs ranged from 1.38-13.74, 3.90-20.00, 0.83-2.99, 0.67-11.95 and 0.00-9.96 mequiv/kg found in refined olive oil, virgin olive oil, canola oil, grape-seed oil and corn oil, respectively. The results showed that PVs of 18.37 percent of imported oil and 62.96 percent of frying oils from restaurant exceeded the maximum acceptable limits set by Institute of Standards and Industrial Research of Iran (ISIRI) (2-20 mequiv/kg for different types of oils). P-anisidine value ranged from 0.89-27.56 mequiv/kg in imported oils and 2.21-30.76 mequiv/kg found in frying oil from restaurants. The TOTOX value increased linearly with peroxide values and p-anisidine values. It ranged from 0.89-76.62. Originality/value-Fried foods are very common in Iranians' diet. A major portion of the edible oils in Iran are imported from other countries through Boushehr port. ISIRI has set maximum acceptable limit for PVs in different oils imported to the country. The possible effects of storage on oil oxidation are the original criteria of this research. The results of the study indicate that inappropriate storage of edible oils and their use in frying applications at restaurants facilitate oil oxidation and deterioration.