14 results on '"Ahmadi, Somayeh"'
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2. Gut microbiota in neurological diseases: Melatonin plays an important regulatory role.
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Ahmadi, Somayeh, Taghizadieh, Mohammad, Mehdizadehfar, Elham, Hasani, Alka, Khalili Fard, Javad, Feizi, Hadi, Hamishehkar, Hammed, Ansarin, Masood, Yekani, Mina, and Memar, Mohammad Yousef
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GUT microbiome , *INTESTINAL barrier function , *NEUROLOGICAL disorders , *ALZHEIMER'S disease , *MELATONIN - Abstract
Melatonin is a highly conserved molecule produced in the human pineal gland as a hormone. It is known for its essential biological effects, such as antioxidant activity, circadian rhythm regulator, and immunomodulatory effects. The gut is one of the primary known sources of melatonin. The gut microbiota helps produce melatonin from tryptophan, and melatonin has been shown to have a beneficial effect on gut barrier function and microbial population. Dysbiosis of the intestinal microbiota is associated with bacterial imbalance and decreased beneficial microbial metabolites, including melatonin. In this way, low melatonin levels may be related to several human diseases. Melatonin has shown both preventive and therapeutic effects against various conditions, including neurological diseases such as Alzheimer's disease, Parkinson's disease, and multiple sclerosis. This review was aimed to discuss the role of melatonin in the body, and to describe the possible relationship between gut microbiota and melatonin production, as well as the potential therapeutic effects of melatonin on neurological diseases. [Display omitted] • The gut microbiota contributes to the production of melatonin from tryptophan. • Melatonin has a beneficial effect on intestinal barrier function and microbial populations. • The potential connection is between melatonin and the microbiome-gut-brain axis. • Enteric microbiota play an important role in brain-related diseases through melatonin modulation in the gut. [ABSTRACT FROM AUTHOR]
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- 2024
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3. The blockade of D1/D2-like dopamine receptors in the lateral periaqueductal gray region affects morphine self-administration with and without exercise in rats.
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Ahmadi, Somayeh, Radahmadi, Maryam, Alizadeh, Safoura, Alaei, Hojatallah, Kargarfard, Mehdi, and Ramshini, Effat
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DOPAMINE receptors , *MORPHINE , *MORPHINE abuse , *REWARD (Psychology) , *RATS - Abstract
Introduction: The periaqueductal gray (PAG) region plays an essential role in the modulation of nociception. Also, lateral PAG (lPAG) is involved in reward circuitry by the dopaminergic system in addiction. The present study investigated the blockade of D1/D2-like dopamine receptors in the lateral PAG region affects morphine self-administration with and without exercise. Methods: Rats were divided into six groups. The rats were initially trained to receive small pellets of food by pressing an active lever in the self administration apparatus. Exercise groups were run on a treadmill at 20m/min, 5 days/week, for 4 weeks before the surgery. Then rats were bilaterally implanted with cannulae in lPAG. The SCH23390 and sulpiride were microinjected into the lPAG, 5min before receiving morphine. Afterward, the animals were allowed to self administer morphine in 2h sessions over 11 consecutive days. At last, the numbers of lever pressing, infusion times and withdrawal symptoms were measured. Results: The results showed the number of active lever pressing was significantly increased in the morphine group compared to other groups in self-infusion during 11 days. Exercise significantly reversed the detrimental effects of morphine self-administration after five days. However, the synergistic effect of injected sulpiride into the lPAG region with exercise training was more pronounced on the amelioration of morphine than on the combinatory effect of SCH23390 with exercise. Conclusion: The findings suggested that the D2 dopamine receptor in the lPAG region was involved in the morphine addiction via the dopaminergic system and exercise training in combination with antagonists could reduce the rewarding properties of morphine. [ABSTRACT FROM AUTHOR]
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- 2021
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4. Evaluation of Various Rosa Damascena Mill. Genotypes Grown under Rainfed Semi-arid Condition.
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Jan Ahmadi, Somayeh, Mortazaeinezhad, Forough, Zeinali, Hossein, Askari-Khorasgani, Omid, and Pessarakli, Mohammad
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DAMASK rose , *GENOTYPES , *ORNAMENTAL plants , *FLOWERING of plants , *PEARSON correlation (Statistics) - Abstract
Rosa damascena Mill L. also known as "Damask Rose" and "Gole Mohammadi" is a well-recognized high value ornamental and medicinal plant, which can be used in food, perfume and medicine industries. This study aimed to analyze the genetic diversity of 10 Rosa damascena genotypes by evaluating their morphological traits, flower yield and oil content to find the best genotype with high productivity under rainfed condition in Lorestan province, Iran. This study was conducted in a completely randomized design trial with three replications. The data analyses, using Pearson's correlation coefficients, showed that flower dry yield per hectare was significantly and positively correlated with, flower dry weight per plant, flowering period, plant height, number of flowers per plant, fresh and dry weight of petals, average weight of each flower, and number of flowers per day. Principal component (PC) analysis revealed that the first three PCs, respectively, called as flower yield, receptacle, and flower size components accounted for 88.33% of the total variation. The genotypes were grouped into four clusters in which the highest genetic distance was observed between Kermanshah and Fars1 genotypes. Fars1 and Yazd1 genotypes had the highest productivity in terms of, respectively, flower yield and oil content and showed the high potential for cultivation under rainfed condition in Lorestan province. [ABSTRACT FROM AUTHOR]
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- 2019
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5. Turbulent drag reduction in channel flow with viscosity stratified fluids.
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Ahmadi, Somayeh, Roccon, Alessio, Zonta, Francesco, and Soldati, Alfredo
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NUMERICAL analysis , *CHANNEL flow , *VISCOSITY , *FLUIDS , *LIQUID-liquid interfaces - Abstract
Highlights • We perform Direct Numerical Simulations to study a viscosity stratified liquid/liquid flow in a turbulent channel. • We use a Phase Field Method to describe the liquid-liquid interaction. • We employ a pseudo-spectral method for the solution of the governing equations. • We analyze the modulation of turbulence induced by the liquid-liquid interface deformation. • We provide a physical explanation of our results based on the analysis of the flow statistics. Abstract In this work we use Direct Numerical Simulation (DNS) to study the turbulent Poiseuille flow of two immiscible liquid layers inside a rectangular channel. A thin liquid layer (fluid 1) flows on top of a thick liquid layer (fluid 2), such that their thickness ratio is h 1 / h 2 = 1 / 9. The two liquid layers have the same density but different viscosities (viscosity-stratified fluids). In particular, we consider three different values of the viscosity ratio λ = ν 1 / ν 2 : λ = 1 , λ = 0.875 and λ = 0.75. Numerical Simulations are based on a Phase Field method to describe the interaction between the two liquid layers. Although a small viscosity ratio is assumed, this physical setup aims at mimicking the situation where water (less viscous fluid) is used to favour the transport of oil (large viscous fluid) inside pipelines. Compared with the case of a single phase flow, the presence of a liquid-liquid interface produces a remarkable turbulence modulation inside the channel, since a significant proportion of the kinetic energy is subtracted from the mean flow and converted into work to deform the interface. This induces a strong turbulence reduction in the proximity of the interface and causes a substantial increase of the volume-flowrate. These effects become more pronounced with decreasing λ. [ABSTRACT FROM AUTHOR]
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- 2018
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6. Optimization of operating parameters in a hybrid wind–hydrogen system using energy and exergy analysis: Modeling and case study.
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Fakehi, Amir Hossein, Ahmadi, Somayeh, and Mirghaed, Mohammad Rezaie
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WIND power , *HYDROGEN production , *HYDROGEN as fuel , *ENERGY consumption , *EXERGY , *PARAMETER estimation - Abstract
In this study, hybrid renewable energy system based on wind/electrolyzer/PEM fuel cell are conceptually modeled, and also, exergy and energy analysis are performed. The energy and exergy flows are investigated by the proposed model for Khaf region-Iran with high average wind speed and monsoon. Exergy and energy analysis framework is made based on thermodynamic, electro-chemical and mechanical model of the different component of hybrid system. Also, the effects of various operating parameters in exergy efficiency are calculated. The results show an optimum wind speed where the exergy efficiency and power coefficient is at maximum level, and also, when the ambient temperature start to be increased in wind turbine, the efficiencies decrease by a great deal for constant wind speeds. Also, the optimum temperature is calculated by exergy analysis in electrolyzer and fuel cell as 353 and the exergy efficiency of electrolyzer decreases by increasing the membrane thickness. Furthermore, pressure changes affect exergy and energy efficiency in PEM fuel cell. Finally, the electrolyzer and fuel cell efficiencies are calculated as 68.5% and 47% respectively. [ABSTRACT FROM AUTHOR]
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- 2015
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7. Numerical modeling of Kelvin-Helmholtz instability by using potential equation.
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Ahmadi, Somayeh
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NUMERICAL analysis , *MATHEMATICAL models , *INCOMPRESSIBLE flow , *TWO-phase flow , *FLUID dynamics , *SHEAR flow , *ALGORITHMS - Abstract
This paper presents a potential flow numerical solution for the Kelvin-Helmholtz Instability (KHI) problem of an incompressible two-phase immiscible fluid in a stratified shear flow. As a problem: the two-fluid model becomes illposed when the slip velocity exceeds a critical value, and computations can be quite unstable before the flow reaches the ill-posed condition. In this work, computational stability of various convection schemes together with the potential equation method for the time derivatives in conjunction with the two-fluid model is analyzed. The normal stress balance (with the normal viscous stress) at the interface for the two-fluid model is carefully implemented to minimize its effect on numerical stability. Von Neumann stability analysis shows that: stability condition for two-fluid with equal kinematic viscosity ratio and inviscid flow, supply numerical stability. Excellent agreement has obtained according to analytical result that existing of imaginary part in solution which specialized this method. The numerical algorithm presented in this work can easily handle two-phase fluid flow with various density and viscosity ratios in rectangular channel. Simulation of this model has implemented by writing a code in FORTRAN programming. [ABSTRACT FROM AUTHOR]
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- 2012
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8. Study of Malachite Green Fading in Water-Ethanol-Ethylene Glycol Ternary Mixtures.
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Samiey, Babak and Ahmadi, Somayeh
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MALACHITE green , *MIXTURES , *WATER , *ETHANOL , *ETHYLENE glycol , *TEMPERATURE effect , *CHEMICAL kinetics , *MATHEMATICAL models - Abstract
The rate constant of malachite green (MG) alkaline fading was measured in water-ethanol-ethylene glycol ternary mixtures. This reaction was studied under pseudo-first-order conditions at 283-303 K. In each series of experiments, the concentration of ethanol was kept constant and the concentration of ethylene glycol was changed. It was shown that due to hydrogen bonding and hydrophobic interaction between MG and alcohol molecules the observed reaction rate constant, $$ k_{\text{obs}} $$, increased in the water-ethanol-ethylene glycol ternary mixtures. The fundamental rate constants of MG fading in these solutions ( $$ k_{1} $$, $$ k_{ - 1} $$ and $$ k_{2} $$) were obtained by the SESMORTAC model. Analysis of $$ k_{1} $$ and $$ k_{2} $$ values in solutions containing constant ethanol concentrations show that in low concentrations of ethylene glycol, hydrogen bonding formed between ethanol and ethylene glycol molecules and in high concentrations of ethylene glycol, ethanol as a solvent for ethylene glycol affected the reaction rate. [ABSTRACT FROM AUTHOR]
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- 2013
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9. Frameworks, quantitative indicators, characters, and modeling approaches to analysis of energy system resilience: A review.
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Ahmadi, Somayeh, Saboohi, Yadollah, and Vakili, Ali
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ENERGY futures - Abstract
The rise of the damage to energy systems caused by both natural and man-made disruptive events and the connection between energy systems and socio-economic systems have motivated the study of energy system resilience. This paper conceptualizes and comprehensively presents a systematic review of the recent literature focused on the analytical, technical, and mathematical points from the standpoint of the energy systems facing disruptive events. To this end, five phases are developed. Firstly, the concept of the energy system resilience is presented, and then the energy resilience characters and the resilience states are introduced and connected. Thirdly, the formulation and indicators of the energy resilience are demonstrated, and modeling features, modeling approach, and solving methods are discussed and compared. Finally, the gaps in the existing literature on the energy system resilience are identified, and future research opportunities are suggested. • A comprehensive review of frameworks and quantitative indicators of energy system resilience. • Summarize typical implementation approaches for the modeling of energy systems. • Propose the characters of the energy systems resilience. • Future directions in the energy system resilience research are discussed. [ABSTRACT FROM AUTHOR]
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- 2021
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10. Age-Dependent Clinical Features and Prognosis of COVID-19 Patients.
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Sami, Ramin, Karbasi, Maryam, Ahmadi, Somayeh Haji, Mansourian, Marjan, Dehghan, Mehrnegar, Khademi, Nilufar, Eslami, Mohammad Javad, and Ghasemi, Khojasteh
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COVID-19 , *OLDER patients , *AGE groups , *PROGNOSIS , *COMPUTED tomography - Abstract
Background: The clinical and paraclinical symptoms of COVID-19 differ across age groups. This study investigated the differences between these parameters and their outcomes in young, middle-aged, and elderly patients admitted to a COVID-19 referral center. Materials and Methods: This retrospective study encompassed patients with COVID-19 hospitalized at Khorshid Hospital (Isfahan, Iran) during February 23 to April 30, 2020. The patients' predisposing conditions, clinical and paraclinical findings, and outcomes were compared among three young, middle-aged, and elderly groups. Results: Of the 1185 hospitalized patients with suspected COVID-19, 1065 were discharged or died at the end of the study. Among these 1065 patients, 654 patients with the mean age of 57.7 years had positive PCR results or typical CT scans and were included in the study, of whom 77 (11.8%), 353 (54%), and 234 (34.2%) patients were assigned into the young, middle-aged, and elderly groups, respectively. There was no statistically significant difference among the three groups regarding the prevalence of clinical symptoms. Moreover, CRP, ESR, WBC, BUN, Cr, and lymphocytes were higher in the elderly group. The ground-glass opacity (GGO) (24.1%), GGO-consolidation (27.4%), and consolidation (10.3%) were the most common CT scan findings in the young, middle-aged, and elderly groups, respectively. Fifty-three patients (8.1%) died, and the mortality rates were 10.36%, 7.27%, and 3.8% in the elderly, middle- aged, and young groups, respectively. Conclusion: COVID 19 symptoms do not depend on age; however, paraclinical findings differ across young, middle-aged, and elderly patients. [ABSTRACT FROM AUTHOR]
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- 2021
11. New‐onset lung sarcoidosis, an adverse event by COVID‐19 or a sign of convalescence; a case report.
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Sadeghi, Somayeh, Mobarakeh, Shadi Reisizadeh, Momenzadeh, Mahnaz, Aria, Amir, Heidarpour, Mitra, Ahmadi, Somayeh Haji, and Naderi, Zohreh
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SARCOIDOSIS , *COVID-19 pandemic , *COVID-19 , *CONVALESCENCE , *LUNGS , *IMMUNOSUPPRESSIVE agents - Abstract
Key Clinical Message: Sarcoidosis is a systemic inflammatory disease able to affect any organ within the body. Sarcoidosis may be the body's secondary response to COVID‐19 infection and a sign of rehabilitation. Early response to the treatments reinforces this hypothesis. The majority of sarcoidosis patients require immunosuppressive therapies, including corticosteroids. Most studies so far have focused on the management of COVID‐19 in patients suffering from sarcoidosis. Nevertheless, the current report aims to present a COVID‐19‐induced sarcoidosis case. Sarcoidosis is a systemic inflammatory disease with granulomas. Still, its etiology is unknown. It often affects the lungs and lymph nodes. A previously healthy 47‐year‐old female was referred with the following chief complaints: atypical chest pain, dry cough, and dyspnea on exertion within a month after COVID‐19 infection. Accordingly, a chest computed tomography revealed multiple conglomerated lymphadenopathies in the thoracic inlet, mediastinum, and hila. A core‐needle biopsy from the nodes revealed non‐necrotizing granulomatous inflammation, sarcoidal type. The sarcoidosis diagnosis was proposed and confirmed by a negative purified protein derivative (PPD) test. Accordingly, prednisolone was prescribed. All symptoms were relieved. A control lung HRCT was taken 6 months later, showing the lesions had disappeared. In conclusion, sarcoidosis may be the body's secondary response to COVID‐19 infection and a sign of disease convalescence. [ABSTRACT FROM AUTHOR]
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- 2023
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12. A one-year hospital-based prospective COVID-19 open-cohort in the Eastern Mediterranean region: The Khorshid COVID Cohort (KCC) study.
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Sami, Ramin, Soltaninejad, Forogh, Amra, Babak, Naderi, Zohre, Haghjooy Javanmard, Shaghayegh, Iraj, Bijan, Haji Ahmadi, Somayeh, Shayganfar, Azin, Dehghan, Mehrnegar, Khademi, Nilufar, Sadat Hosseini, Nastaran, Mortazavi, Mojgan, Mansourian, Marjan, Mañanas, Miquel Angel, Marateb, Hamid Reza, and Adibi, Peyman
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COVID-19 , *MEDICAL personnel , *COMORBIDITY , *LENGTH of stay in hospitals , *PATIENT selection , *MEDICAL care - Abstract
The COVID-19 is rapidly scattering worldwide, and the number of cases in the Eastern Mediterranean Region is rising. Thus, there is a need for immediate targeted actions. We designed a longitudinal study in a hot outbreak zone to analyze the serial findings between infected patients for detecting temporal changes from February 2020. In a hospital-based open-cohort study, patients are followed from admission until one year from their discharge (the 1st, 4th, 12th weeks, and the first year). The patient recruitment phase finished at the end of August 2020, and the follow-up continues by the end of August 2021. The measurements included demographic, socio-economics, symptoms, health service diagnosis and treatment, contact history, and psychological variables. The signs improvement, death, length of stay in hospital were considered primary, and impaired pulmonary function and psychotic disorders were considered main secondary outcomes. Moreover, clinical symptoms and respiratory functions are being determined in such follow-ups. Among the first 600 COVID-19 cases, 490 patients with complete information (39% female; the average age of 57±15 years) were analyzed. Seven percent of these patients died. The three main leading causes of admission were: fever (77%), dry cough (73%), and fatigue (69%). The most prevalent comorbidities between COVID-19 patients were hypertension (35%), diabetes (28%), and ischemic heart disease (14%). The percentage of primary composite endpoints (PCEP), defined as death, the use of mechanical ventilation, or admission to an intensive care unit was 18%. The Cox Proportional-Hazards Model for PCEP indicated the following significant risk factors: Oxygen saturation < 80% (HR = 6.3; [CI 95%: 2.5,15.5]), lymphopenia (HR = 3.5; [CI 95%: 2.2,5.5]), Oxygen saturation 80%-90% (HR = 2.5; [CI 95%: 1.1,5.8]), and thrombocytopenia (HR = 1.6; [CI 95%: 1.1,2.5]). This long-term prospective Cohort may support healthcare professionals in the management of resources following this pandemic. [ABSTRACT FROM AUTHOR]
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- 2020
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13. Sequestration inside the yeast vacuole may enhance Helicobacter pylori survival against stressful condition.
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Siavoshi, Farideh, Heydari, Samira, Shafiee, Mahsa, Ahmadi, Somayeh, Saniee, Parastoo, Sarrafnejad, Abdolfattah, and Kolahdoozan, Shadi
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YEAST , *HELICOBACTER pylori , *EUKARYOTIC cells , *CYTOTOXINS , *FLUORESCENCE in situ hybridization - Abstract
Abstract Vacuole of eukaryotic cells, beyond intracellular digestion plays additional roles such as storage of nutrients that provide favorable conditions for bacterial survival. In this study, occurrence of H. pylori inside the vacuole of Candida yeast was studied and the role of vacuolating cytotoxin A (VacA) in constructing the vacuole was discussed. One gastric C andida yeast was used for Live/Dead stain and fluorescence in situ hybridization (FISH) with universal bacterial probe. Yeast total DNA was used for amplification of full-length bacterial 16S rDNA as well as H. pylori -specific 16S rDNA and vacA alleles. Vacuoles were isolated from yeast cells and stained with fluorescent yeast vacuole membrane marker MDY-64. DNA extracted from vacuoles was used for amplification of H. pylori -specific 16S rDNA. Fluorescent microscopy showed occurrence of viable bacteria inside the vacuole of intact Candida yeast cells. FISH showed intracellular bacteria as fluorescent spots inside the vacuole of mother and daughter yeast cells, suggesting bacterial transmission to next generations of yeast. Sequencing of amplified products of bacterial 16S rDNA and amplification of H. pylori 16S rDNA and vacA confirmed the identity of intracellular bacteria as H. pylori. Isolated vacuoles were stained with membrane-specific marker and H. pylori 16S rDNA was amplified from their DNA content. Results of this study suggest yeast vacuole as a specialized niche for H. pylori. It appears that sequestration inside the vacuole may enhance bacterial survival. Highlights • Vacuole of eukaryotic cells provides favorable conditions for bacterial survival. • Sequestration inside the vacuole may enhance bacterial survival. • Yeast vacuole can serve as a specialized niche for H. pylori. • VacA might have played a crucial role in constructing the vacuole for H. pylori. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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14. Association of systemic complications with mortality in coronavirus disease of 2019: A cohort study on intensive care unit patients.
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Ashraf, Mohammad, Sherafat, Alireza, Naderi, Zohre, Sami, Ramin, Soltaninejad, Forogh, Khodadadi, Saba, Mashayekhbakhsh, Sanaz, Sharafi, Negar, Ahmadi, Somayeh, Shayganfar, Azin, Zand, Iman, Ajami, Ali, and Shirani, Kiana
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COVID-19 , *CONFIDENCE intervals , *CRITICALLY ill , *LUNG diseases , *PATIENTS , *RETROSPECTIVE studies , *ARTIFICIAL respiration , *HOSPITAL care , *DESCRIPTIVE statistics , *ODDS ratio , *COMORBIDITY , *LONGITUDINAL method , *DISEASE complications ,CHRONIC kidney failure complications - Abstract
Background: Since the beginning of the coronavirus disease of 2019 (COVID-19) pandemic, concerns raised by the growing number of deaths worldwide. Acute respiratory distress syndrome (ARDS) and extrapulmonary complications can correlate with prognosis in COVID-19 patients. This study evaluated the association of systemic complications with mortality in severely affected COVID-19 patients. Materials and Methods: This retrospective study was done on 51 intensive care unit (ICU)-admitted COVID-19 adult patients who were admitted to the ICU ward of Khorshid hospital, affiliated with Isfahan University of Medical Sciences. Only the patients who had a definite hospitalization outcome (dead vs. survivors) were included in the study. Daily clinical and paraclinical records were used to diagnose in-hospital complications in these patients. Results: The sample was comprised of 37 males (72.5%) and 14 females (27.4%). The median age of patients was 63 years (Min: 20, Max: 84), with the mortality rate of 47.1%. In total, 70.6% of patients had at least one coexisting disorder. Chronic kidney disease was associated with the worse outcome (29.16% of dead patients against 3.70 of survived ones). Mechanical ventilation was used in 58.8% of patients. Patients who had received invasive ventilation were more likely to die (87.50% of dead patients against 7.40 of survivors), Complications including sepsis and secondary infections (odds ratio: 8.05, confidence interval: 2.11–30.63) was the strongest predictors of mortality. Conclusion: Complications including sepsis and secondary infections can increase the risk of death in ICU-admitted COVID-19 patients. Therefore, it is substantial that the physicians consider preventing or controlling these complications. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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