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1.
Sci Rep ; 14(1): 12354, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38811571

RESUMO

In this paper, a novel phononic crystal fiber with conical input is introduced for coupling environmental acoustic waves to the fiber core. Environmental acoustic waves can be focused and coupled to the core through conical input. In the first step, a cone shape coupler has been considered for coupling the incident acoustic waves to the core region. This initial idea has a significant acoustic energy loss. This disadvantage encourages us to design a new phononic crystal fiber without it. Designed structure includes a phononic crystal fiber with conical input meaning solid rods have been shaped in conical way at the input section of fiber. By using this structure, environmental acoustic waves can be properly coupled to the core region of the fiber. Acoustic wave leakage to outside of the Phononic crystal fiber has been extremely decreased in comparison with initial coupler. Experimental results indicate that environmental acoustic waves can be focused and coupled to the core region by phononic crystal fiber with conical input.

2.
Vet Med Sci ; 10(3): e1442, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578271

RESUMO

BACKGROUND: Blastocystis sp. is a zoonotic protozoan parasite, and there is limited information about its molecular prevalence and subtypes (STs) distribution in camels globally, especially in Iran. OBJECTIVES: This study aimed to examine the prevalence, STs distribution, and zoonotic potential of Blastocystis sp. in one-humped and two-humped camels in Ardabil province, northwestern Iran. METHODS: A PCR-sequencing tool using the SSU rRNA gene was employed to examine the occurrence and genetic variation of Blastocystis sp. in 150 faecal samples from Bactrian (Camelus bactrianus, 50 samples) and Dromedary (Camelus dromedarius, 100 samples) camels in Ardabil province. RESULTS: The overall prevalence of Blastocystis sp. in camels was determined to be 12% (18/150) through microscopy and PCR analyses. Phylogenetically, this study identified three distinct zoonotic STs: ST7, ST10, and ST14. ST10 was the most prevalent, comprising 50% (9/18) of the isolated STs from camels. ST14 closely followed with 38.9% (7/18), while ST7 made up 11.1% (2/18) of the total STs. In brief, ST10, ST14, and ST7 represented 50% (7/14), 35.7% (5/14), and 14.3% (2/14) of the Blastocystis-positive cases in one-humped camels, respectively. Further, each of the ST10 and ST14 accounted for 50% (2/4) of the Blastocystis-positive samples in two-humped camels. An analysis of the available data reveals that out of the 37-44 identified Blastocystis STs, 15 (ST1-ST7, ST10, ST14, ST15, ST21, ST24, ST25, ST26, and ST30) have been reported in camels. The predominant STs observed are ST10 and ST14. Furthermore, among the 15 zoonotic STs (ST1-ST10, ST12-ST14, ST16, and ST23) of Blastocystis reported thus far, nine zoonotic STs (ST1-ST7, ST10, and ST14) have been found in camels. CONCLUSIONS: These findings indicate that camels serve as a proper reservoir for a diverse array of Blastocystis STs and thereby can play a significant role in the transmission of this protozoan infection to humans, animals, and water reservoirs.


Assuntos
Infecções por Blastocystis , Blastocystis , Humanos , Animais , Blastocystis/genética , Camelus , Infecções por Blastocystis/epidemiologia , Infecções por Blastocystis/veterinária , Infecções por Blastocystis/parasitologia , Epidemiologia Molecular , Irã (Geográfico)/epidemiologia
3.
J Eukaryot Microbiol ; 71(3): e13019, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38225853

RESUMO

A total of 360 fecal samples were randomly collected from 150 cattle, 150 sheep, and 60 humans (30 people with close animal contact and 30 individuals without close animal contact) at 10 farms in Ilam, western Iran from June 2022 to August 2023. All samples were directly examined for Blastocystis by zinc sulfate flotation, followed by microscopic observation. Positive samples were further subtyped using conventional PCR and sequencing methods. A mean prevalence of 5.3% (16/300) was estimated for Blastocystis infection among examined animals, with 6% and 4.7% for cattle and sheep, respectively. Among the people who had close and non-close animal contact, 16.7% (5/30) and 3.3% (1/30) were infected with Blastocystis, respectively (p < 0.05). All 22 positive samples were successfully sequenced at the SSU rRNA locus. Accordingly, Blastocystis isolates infecting domestic animals in Ilam belonged to the four STs (ST1-ST3, and ST10). Of the 16 animal isolates, nine sequences (four ST10, three ST3, and two ST1) were related to cattle, and seven sequences (three ST10, two ST3, and two ST2) were isolated from sheep. Among the six human isolates, ST3 was the most predominant ST, followed by STs 1, 2, 6, and 7 (one case each). Of note, ST1-ST3 were isolated in various farms both from animals and their breeders, which indicates the possible circulation of these STs between animal and human populations.


Assuntos
Infecções por Blastocystis , Blastocystis , Doenças dos Bovinos , Fezes , Zoonoses , Animais , Bovinos , Blastocystis/genética , Blastocystis/classificação , Blastocystis/isolamento & purificação , Irã (Geográfico)/epidemiologia , Ovinos , Infecções por Blastocystis/veterinária , Infecções por Blastocystis/parasitologia , Infecções por Blastocystis/epidemiologia , Humanos , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/epidemiologia , Fezes/parasitologia , Zoonoses/parasitologia , Animais Domésticos/parasitologia , Doenças dos Ovinos/parasitologia , Doenças dos Ovinos/epidemiologia , Filogenia , Prevalência , DNA de Protozoário/genética
4.
Biotechnol Appl Biochem ; 71(3): 565-583, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38246886

RESUMO

The commercial production of multifunctional, biocompatible, and biodegradable biopolymers such as poly-γ-glutamic acid via microbial fermentation requires the development of simple and cheap methods for mass production. This study optimized the poly-γ-glutamic acid production of Bacillus licheniformis ATCC 9945a in several steps. At first, the most critical components of the culture medium, including l-glutamic acid, citric acid, and glycerol, were selected by screening nine factors through the Plackett-Burman experimental design and then were optimized using the response surface method and the central composite design algorithm. Under optimal conditions, the production of poly-γ-glutamic acid increased by more than 4.2 times from 11.2 to 47.2 g/L. This is one of the highest production rates of this strain in submerged batch fermentation reported so far using the optimized medium compared to the conventional base medium. A novel and efficient sudden pulse feeding strategy (achieved by a novel one-factorial statistical technique) of l-glutamic acid to the optimized medium increased biopolymer production from 47.2 to 66.1 g/L, the highest value reported in published literature with this strain. This simple, reproducible, and cheap fermentation process can considerably enhance the commercial applications of the poly-γ-glutamic acid synthesized by B. licheniformis ATCC 9945a.


Assuntos
Bacillus licheniformis , Meios de Cultura , Ácido Glutâmico , Ácido Poliglutâmico , Ácido Poliglutâmico/biossíntese , Ácido Poliglutâmico/análogos & derivados , Ácido Poliglutâmico/metabolismo , Ácido Poliglutâmico/química , Bacillus licheniformis/metabolismo , Bacillus licheniformis/crescimento & desenvolvimento , Meios de Cultura/química , Meios de Cultura/metabolismo , Ácido Glutâmico/metabolismo , Fermentação , Projetos de Pesquisa
5.
Neurodegener Dis Manag ; 13(6): 351-369, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38357803

RESUMO

Neuronal death, decreased activity or dysfunction of neurotransmitters are some of the pathophysiological reasons for neurodegenerative diseases like Alzheimer's, Parkinson's and multiple sclerosis. Also, there is evidence for the role of infections and infectious agents in neurodegenerative diseases and the effect of some metabolites in microorganisms in the pathophysiology of these diseases. In this study, we intend to evaluate the existing studies on the role of infectious agents and their metabolites on the pathophysiology of neurodegenerative diseases. PubMed, Scopus, Google Scholar and Web of Science search engines were searched. Some infectious agents have been observed in neurodegenerative diseases. Also, isolations of some fungi and microalgae have an improving effect on Parkinson's and Alzheimer's.


Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Doença de Parkinson , Humanos , Doenças Neurodegenerativas/metabolismo , Doença de Alzheimer/metabolismo , Doença de Parkinson/metabolismo
6.
Sci Rep ; 12(1): 16096, 2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36167882

RESUMO

A concentric cylindrical cloak is showed here to achieve the acoustic cloaking phenomenon. The introduced structure consists of MNE layers and water in MNE substrate in the MHz frequency range. Due to avoiding the incoming acoustic waves by the shell, the object can be hidden inside the cylindrical area of any shape. In order to improve the quality of cloaking, we have optimized the desired shell by considering the manufacturing technology. We show that an optimized, acoustic cloak based on composite lattice structure can reduce the scattering of an object more than a 20-layer realization of acoustic cloak based on multilayer cylindrical structure. This design approach can substantially simplify the fabrication of cloaking shells. In this research, to study the acoustic distribution of the desired structure, finite element method (FEM) has been used to analyze the structure in two dimensions and a cloak of natural materials with isotropic properties has been designed using effective medium theory.

7.
Sci Rep ; 12(1): 10522, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35732664

RESUMO

In this investigation, a phononic crystal-based fiber is proposed for energy harvesting application in metalworking factories. Phononic crystal plays the role of cladding in elastic fiber structure. Each of single-core fibers includes a tungsten hollow cylinder in central region which its internal radius is different in three single-core fibers. Incident waves with central frequency from 25 to 40 kHz of 1/3 octave band are confined in the core region of proposed elastic fibers and transmitted to desired distance. High confinement and transmission ability without significant longitudinal loss make this structure distinct from the other phononic crystals-based energy harvesters. By utilizing of a piezoelectric film at the end of fiber cores, mechanical energy is converted to electrical energy. As proposed elastic fibers confine the applied waves with high quality, the obtained output power is enhanced up to 800 times in comparison with the bare case. Maximum value of extinction ratio between all single core fibers is equal to - 23 dB. Also, longitudinal loss is almost equal to 0.9 dB/km.

8.
Artigo em Inglês | MEDLINE | ID: mdl-35273645

RESUMO

SARS-CoV-2 is a novel coronavirus and the cause of the recent pandemic; it is an enveloped ß-coronavirus. SARS-CoV-2 appear in the Wuhan City of China for the first time and outspread worldwide quickly. Due to its person-to-person fast transmission, COVID-19 is becoming a global problem. SARS-CoV-2 enter into cells by using ACE2 receptors that are numerous in the lungs and finally can cause acute respiratory distress syndrome (ARDS). Dry cough, sore throat, fever, body pain, headache, GIT discomfort, diarrhoea, and fatigue are some of the COVID-19 symptoms. There is no definite and certain treatment for disease caused by SARS-CoV-2 till now. Some pharmacological effects of toxins, toxoids, and venoms have been proven, and their effects on some diseases have been evaluated. This study aimed to investigate the role of toxins, toxoids, and venom in the pathophysiology of COVID-19 disease.

9.
Prep Biochem Biotechnol ; 52(8): 961-968, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34974825

RESUMO

Poly-γ-glutamic acid (γ-PGA) is a versatile biopolymer with widespread applications in the food, pharmaceutical, and medical industries. One of the main challenges in expanding γ-PGA industrial applications is the high cost of production. Developing an efficient and low-cost fermentation process such as bacterial cultivation with pulsed feeding can significantly reduce production costs. Thus, initially, a new pulsed-feeding strategy of citrate and glutamate was developed for γ-PGA production enhancement in the fed-batch culture of Bacillus licheniformis ATCC 9945a. Then, the effects of pulse number, feeding amount, feeding times, the addition time of calcium and manganese solutions, the pH of the added citrate solution, and the concentration of feed stock solutions of pulse-feeds on γ-PGA production were investigated. Under optimal conditions: feeding two pulses at 8 and 24 hours of culture, 20 g citrate and glutamate per liter of culture medium per pulse (about 52 mL of each of citrate and glutamate feeding solutions prepared with a concentration of 384 g/L by adding distilled water) about 88 ± 4 g/L of γ-PGA was obtained. It is one of the highest values ever reported for γ-PGA production with Bacillus licheniformis ATCC 9945a, of course with a much simpler process than the other fed-batch processes.


Assuntos
Bacillus licheniformis , Bacillus licheniformis/metabolismo , Citratos , Ácido Cítrico , Fermentação , Ácido Glutâmico/metabolismo , Ácido Poliglutâmico/análogos & derivados
10.
Biol Trace Elem Res ; 200(6): 2639-2650, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34448983

RESUMO

Many aspects of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its disease, COVID-19, have been studied to determine its properties, transmission mechanisms, and pathology. These efforts are aimed at identifying potential approaches to control or treat the disease. Early treatment of novel SARS-CoV-2 infection to minimize symptom progression has minimal evidence; however, many researchers and firms are working on vaccines, and only a few vaccines exist. COVID-19 is affected by several heavy metals and their nanoparticles. We investigated the effects of heavy metals and heavy metal nanoparticles on SARS-CoV-2 and their roles in COVID-19 pathogenesis. AgNPs, AuNPs, gold-silver hybrid NPs, copper nanoparticles, zinc oxide, vanadium, gallium, bismuth, titanium, palladium, silver grafted graphene oxide, and some quantum dots were tested to see if they could minimize the severity or duration of symptoms in patients with SARS-CoV-2 infection when compared to standard therapy.


Assuntos
COVID-19 , Nanopartículas Metálicas , Metais Pesados , Vacinas , Ouro , Humanos , SARS-CoV-2 , Prata
11.
Sci Rep ; 11(1): 19198, 2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34584199

RESUMO

In this study, a novel elastic phononic crystal fiber has been presented for the first time. This proposed structure can expand the sonic communications field, significantly. In order to realize the elastic fiber performance, solid-solid phononic crystal has been utilized. The phononic crystal structure operates as cladding in surroundings and central region acts as core of fiber by elimination of rods. Incident acoustic waves with transverse polarization have confined and propagated in the core region of the phononic crystal fiber. Two types of phononic crystal fiber with different core radii have been investigated. Incident elastic waves can confine in the core region with confinement factor higher than 500. Also, longitudinal losses have been achieved low and equal to 0.35 dB/km.

12.
Biol Trace Elem Res ; 199(7): 2475-2481, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32901413

RESUMO

All the world is involved in the COVID-19 disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Coronavirus is a positive-sense RNA and has an envelope. There is no specific drug for this disease and treatment methods are limited. Malnutrition and electrolyte imbalance can make dysfunction in the immune system and impairment of the immune system causes increasing the risk of infection. Understanding the aspects of biological features of the virus will help the development of diagnostic tests, pharmacological therapies, and vaccines. Here, we review and discuss increasing and decreasing some trace elements and imbalance of serum and plasma electrolytes involving in COVID-19.


Assuntos
COVID-19 , Oligoelementos , Testes Diagnósticos de Rotina , Eletrólitos , Humanos , SARS-CoV-2
13.
J Biochem Mol Toxicol ; 33(11): e22398, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31557371

RESUMO

Cyclophosphamide (CTX) has been broadly used in the clinic for the treatment of autoimmune disorders and ovarian cancer. The process of chemotherapy has significant toxicity in the reproductive system as it has detrimental effects on folliculogenesis, which leads to an irreversible premature ovarian failure (POF). Coenzyme Q10 (CoQ10) has positive impacts on the reproductive system due to its antioxidant properties, protecting the cells from free-radical oxidative damage and apoptosis. However, little is known about the possible synergistic effect of CTX and CoQ10 on the expression of genes involved in folliculogenesis, such as proliferation cell nuclear antigen (PCNA) and follicle-stimulating hormone receptor (FSHR). A total of 32 NMRI mice were applied and divided into four groups, including healthy control, CTX, CTX + CoQ10, and CoQ10 groups. The effects of CoQ10 on CTX-induced ovarian injury and folliculogenesis were examined by histopathological and real-time quantitative reverse transcription-polymerase chain reaction analyses. The rates of fertilization (in vitro fertilization), embryo development, as well as the level of reactive oxygen species (ROS) in metaphase II (MII) mouse oocytes after PMSG/HCC treatment were also assessed. Results showed that the treatment with CTX decreased the mRNA expression of PCNA and FSHR, IVF rate, and embryo development whereas the application of CoQ10 successfully reversed those factors. CoQ10 administration significantly enhanced histological morphology and decreased ROS levels and the number of atretic follicles in the ovary of CTX-treated mice. In conclusion, it seems that the protective effect of CoQ10 is exerted via the antioxidant and proliferative properties of this substance on CTX-induced ovarian damage.


Assuntos
Antioxidantes/farmacologia , Ciclofosfamida/farmacologia , Insuficiência Ovariana Primária/induzido quimicamente , Antígeno Nuclear de Célula em Proliferação/genética , Receptores do FSH/genética , Ubiquinona/análogos & derivados , Regulação para Cima/efeitos dos fármacos , Animais , Antioxidantes/administração & dosagem , Ciclofosfamida/administração & dosagem , Sinergismo Farmacológico , Desenvolvimento Embrionário/efeitos dos fármacos , Feminino , Fertilização in vitro/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Masculino , Camundongos , Modelos Animais , Oócitos/metabolismo , Ovário/efeitos dos fármacos , Ovário/patologia , Indução da Ovulação , RNA Mensageiro/genética , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ubiquinona/administração & dosagem , Ubiquinona/farmacologia
14.
J Environ Health Sci Eng ; 17(1): 505, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31321057

RESUMO

[This retracts the article DOI: 10.1186/s40201-015-0216-9.].

20.
Iran J Biotechnol ; 14(2): 13-18, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28959321

RESUMO

BACKGROUND: Bacterial Extracellular Polymeric Substances (EPS) are environmental friendly and versatile polymeric materials that are used in a wide range of industries such as: food, textile, cosmetics, and pharmaceuticals. To make the production process of the EPS cost-effective, improvements in the production yield is required which could be implemented through application of processes such as optimized culture conditions, and development of the strains with higher yield (e.g. through genetic manipulation), or using low-cost substrates. OBJECTIVES: In this work, the effects of carbon and nitrogen sources were studied in order to improve the EPS production by the submerged cultivation of Chryseobacterium indologenes MUT.2. MATERIALS AND METHODS: The mesophilic microorganism Chryseobacterium indologenes MUT.2, was grown and maintained in the Luria Bertani agar. The initial basal medium contained: glucose (20 g.L-1), yeast extracts (5 g.L-1), K2HPO4 (6 g.L-1), NaH2PO4 (7 g.L-1), NH4CL (0.7 g.L-1), and MgSO4 (0.5 g.L-1). For evaluating the carbon and nitrogen sources' effect on the fermentation performance, cultures were prepared in 500 mL flasks filled with 300 mL of the medium. The single-factor experiments based on statistics was employed to evaluate and optimize the carbon and nitrogen sources for EPS production in the liquid culture medium of Chryseobacterium indologenes MUT.2. RESULTS: The preferred carbon-sources, sucrose and glucose, commonly gave the highest EPS production of 8.32 and 6.37 g.L-1, respectively, and the maximum EPS production of 8.87 g.L-1 was achieved when glutamic acid (5 g.L-1) was employed as the nitrogen source. CONCLUSIONS: In this work, the culture medium for production of EPS by Chryseobacterium indologenes MUT.2 was optimized. Compared to the basal culture medium in shake-flasks and stirred tank bioreactor, the use of optimized culture medium has resulted in a 53% and 73% increase in the EPS production, respectively.

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