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Comparative investigation of different chemicals on the germination of two aquatic microsporidia
No full textMicrosporidia are eukaryotic obligatory intracellular parasites that infect a wide range of vertebrates and invertebrate hosts. Spores infect target cells of the host by transferring their sporoplasm through a distinctive polar tube. This study investigated how selected chemicals influence the germination of two newly discovered microsporidia species from central-western Iran. Spores of Parathelohania iranica were extracted from infected larvae of Anopheles superpictus s.l. and purified by the Percoll discontinuous density gradient method. Because of the small number of spores per copepod, extraction and purification were not performed for spores of the microsporidium infecting Paracyclops chiltoni. Both spores were exposed to KCl, NaCl, KI, NaI, and H2O2 and the effects of concentration (0.5, 1.5, and 2.5 M), pH (7.0, 9.0, and 11.0), temperature (4 °C and 25 °C), and duration of exposure (10 and 30 min) on spore germination were investigated and compared. This study indicated that the type of the ionic nature of the surrounding environment of spores plays an important role in the release of polar tubes of both microsporidia. Additionally, anions played a more significant role than cations. This effect was directly related to concentration, temperature, and time. However, no specific pattern was recognized at different alkaline pH levels. Hydrogen peroxide was not effective in releasing the polar tubes of the spores of these microsporidia. This study demonstrated the comparative role of some chemicals and the associated factors in the release of the polar tube of two aquatic microsporidia. Future research should examine the practical value of these findings in the mass production of candidate microsporidia for the biological control of pest invertebrate hosts
A nanoscale electrochemical guanine DNA-biosensor based on a flower-like nanocomposite of Tb-doped ZnO for the sensitive determination of pemetrexed
No full textPemetrexed is an antineoplastic drug used in chemotherapeutic treatments, especially in malignant mesothelioma and non-small cell lung carcinoma, but can also cause a variety of complications, like stomach pain, nausea, burning, vomiting, numbness, and tingling, emphasizing the need for an approach to quantify the drug in biological matrices. Herein, a DNA-based biosensor was introduced for pemetrexed determination. A hydrothermal approach was used for synthesizing flower-like nanoparticles (NPs) of zinc oxide (ZnO) doped with Tb (FL-NP Tb3+/ZnO). Moreover, energy dispersive X-ray (EDX), field-emission scanning electron microscopy (FESEM), zeta potential, Brunauer-Emmett-Teller (BET), and X-ray diffraction (XRD) analyses were used for characterizing the as-prepared nanocomposite. According to the impedance analysis, FL-NP Tb3+/ZnO was accompanied by very good electrochemical functions for a simple transfer of electrons. In the case of the immobilization of double-stranded deoxyribonucleic acid (ds-DNA) on the FL-NP Tb3+/ZnO and polypyrrole (PP)-modified pencil graphite electrode (ds-DNA/PP/FL-NP Tb3+/ZnO/PGE), a considerable enhancement was found in the electrochemical oxidation of guanine in ds-DNA residue bases. Since there was an interaction between ds-DNA and pemetrexed, the voltammetric current of guanine over the ds-DNA/PP/FL-NP Tb3+/ZnO/PGE declined in the presence of pemetrexed in the electrolytic solution. Moreover, under optimum conditions (25 mg L−1 of ds-DNA and 10 min incubation time, in acetate buffer at 25 °C), a linear decrease in the guanine signal was observed on the ds-DNA/PP/FL-NP Tb3+/ZnO/PGE as the pemetrexed concentration increased in the range from 0.001 μM to 175.0 μM with a limit of detection of 0.17 nM. Finally, the new DNA-based biosensor was successfully used for determining pemetrexed in real samples, indicating its application potential
Superparamagnetic iron oxide nanoparticle-loaded nanodroplets for dual-modal ultrasound/magnetic resonance imaging-guided drug delivery
No full textRecently, ultrasound-sensitive nanodroplets (NDs) have been developed as controlled-release drug delivery systems. However, the high pressure and frequency of ultrasound (US) waves were needed to induce acoustic droplet vaporization (ADV) for triggering drug release. In this study, folic acid (FA) targeted NDs with an alginate (Alg) shell containing methotrexate (MTX) as a chemotherapy drug and superparamagnetic iron oxide nanoparticles (SPIONs) as an ADV promotor and a magnetic resonance (MR) imaging contrast agent were successfully synthesized. The physicochemical properties of NDs including the size, morphology, ultrasound echogenicity, magnetic properties, MR relaxivity, and drug release patterns were evaluated. In vitro ultrasound imaging showed that NDs can generate highly echogenic microbubbles (MBs). Additionally, SPIONs/MTX ND with a relaxivity value of 87.59 mM−1 s−1 can act as a T2-weighted MRI contrast agent. Folate receptor-positive 4T1 cells and folate receptor-negative L929 cells were utilized. The cell experiments and blood cytotoxicity evaluations proved that SPIONs/MTX-FA NDs are highly biocompatible with no hemolytic activity. The cellular uptake of FA-functionalized NDs increased by 3.2-fold compared to that of non-functionalized NDs, and it was further enhanced, more than three times, after US exposure. The MTT assay demonstrated that the cell viability for ultrasound-exposed samples treated with SPIONs/MTX NDs was significantly decreased in comparison to blank NDs which is related to more drug release from NDs. It was concluded that SPIONs/MTX-FA NDs have significant potential as theranostic agents for dual-modal US/MRI-guided and acoustically-activated drug delivery
Fisetin-metformin co-loaded in mesoporous silica nanoparticles (MSNs) inhibited triple negative breast cancer proliferation
No full textObjective(s): Herbal compounds with cytotoxicity have been of great interest in recent years to improve cancer treatment methods. Fisetin is an anti-cancer herbal compound with low solubility in aqueous systems. Metformin is another compound with anti-cancer effects. In this study, the combined effect of fisetin and metformin was investigated using mesoporous silica nanoparticles (MSNs) in breast cancer cell lines. Materials and Methods: After the synthesis of nanoparticles, they were characterized using XRD, TEM, SEM. The DLS test showed a size of 143.4 nm with zeta-potential -39.1 mV. Fisetin and metformin were loaded into nanoparticles and loading was confirmed by FTIR. The toxicity of different concentrations of free drug (metformin, fisetin, fisetin-metformin) and Nanoformulations (metformin, fisetin and nano-fisetin-metformin) was investigated on two breast cancer lines MCF7 and MDA-MB-231. Results: Fisetin-metformin co-loaded in MSNs showed the highest cytotoxicity among all formulations in both cell lines. The inhibition of colony formation and migration rate was effectively observed in the co-treatment of cells with fisetin and metformin loaded in nanoparticles compared to single treatments. The expression of tumor suppressor miR-200b-3p and miR-34a-5p showed that fisetin increased the expression of these tumor suppressors compared to the control. Conclusion: The anti-cancer effect of fisetin-metformin in combination increased the expression of tumor suppressors due to the regulation of a wide range of gene network involving in cancer progress. The obtained results highlight the use of MSN as an effective drug delivery system for simultaneous delivery of herbal cytotoxic compounds in cancer
Immunoinformatics-based multi-epitope vaccine design for the re-emerging monkeypox virus
No full textBackground: On May 7, 2022, WHO reported a new monkeypox case. By May 2023 over 80,000 cases had been reported worldwide outside previously endemic nations. (This primarily affected the men who have sex with men (MSM) community in rich nations). The present research aims to develop a multi-epitope vaccine for the monkeypox virus (MPXV) using structural and cell surface proteins. Methods: The first part of the research involved retrieving protein sequences. The Immune Epitope Database (IEDB) was then used to analyze the B and T lymphocyte epitopes. After analyzing the sensitizing properties, toxicity, antigenicity, and molecular binding, appropriate linkers were utilized to connect selected epitopes to adjuvants, and the structure of the vaccine was formulated. Algorithms from the field of immunoinformatics predicted the secondary and tertiary structures of vaccines. The physical, chemical, and structural properties were refined and validated to achieve maximum stability. Molecular docking and molecular dynamic simulations were subsequently employed to assess the vaccine's efficacy. Afterward, the ability of the vaccine to interact with toll-like receptors 3 and 4 (TLR3 and TLR4) was evaluated. Finally, the optimized sequence was then introduced into the Escherichia coli (E. coli) PET30A + vector. Results: An immunoinformatics evaluation suggested that such a vaccine might be safe revealed that this vaccine is safe, hydrophilic, temperature- and condition-stable, and can stimulate innate immunity by binding to TLR3 and TLR4. Conclusion: Our findings suggest that the first step in MPXV pathogenesis is structural and cell surface epitopes. In this study, the most effective and promising epitopes were selected and designed through precision servers. Furthermore, through the utilization of multi-epitope structures and a combination of two established adjuvants, this research has the potential to be a landmark in developing an antiviral vaccine against MPXV. However, additional in vitro and in vivo tests are required to confirm these results
Prevalence of Pathological Lesion Due to Mild Head Trauma in Computed Tomography Scan of Patients’ Brains
No full textBackground and aims: This study investigated the prevalence of pathological lesions on the computed tomography (CT) scans of the brains of patients with mild head trauma based on the New Orleans-Canadian criteria at Shahrekord Ayatollah Kashani Hospital, Iran. Methods: All patients referred to the Emergency Department of Shahrekord Ayatollah Kashani Hospital in 2019 with a history of head trauma were included in this cross-sectional, descriptive-analytical study according to the criteria of mild head trauma. Then, the relevant checklist was used to record the patients’ level of consciousness, demographic information, and cause of trauma. Finally, the data were analyzed using SPSS 18, and the patient’s lesions were reported accordingly. Results: Out of 143 patients, 89 were males, and 54 were females in this study. Falling from a height was the cause of head trauma in most patients (43.3%). Among all patients, the CT scans of six patients were abnormal and had lesions. The vomiting had a significant relationship with the results of the CT scan, and for patients with mild head trauma, the Canadian and New Orleans indices had the same clinical importance. Conclusion: According to the results of the present study, the New Orleans index could identify more patients as CT scan candidates than the Canadian index; however, there was no difference in the final result (the presence of a pathological lesion in the CT scan) between these two indices. The New Orleans index has more features than the Canadian index, but its results are not different from the Canadian index. Thus, we believe that using the Canadian index can reduce imaging rates, costs, and protection from the side effects of radiation
Clustering 46 Asian Countries According to the Trend of Breast Cancer Incidence Rate from 1990-2016: An Application of Growth Mixture Model
No full textBackground: Breast cancer is the second cause of death in Asian countries, and 39 of all new breast cancer cases are diagnosed in Asia. The current study was designed to identify different patterns of breast cancer incidence rates among Asian countries. Methods: In this secondary analysis study, information about the incidence rates of female breast cancer for 46 Asian countries was extracted from the Gapminder website from 1990 to 2016, and a growth mixture model was developed to describe the growth patterns and identify the main longitudinal trends in Mplus 7.4. Finally, the estimated trend in each cluster was characterized by intercept (the rate at 1990) and slope (the observed annual trend changes). Results: Our findings suggested an overall increasing trend throughout the continent, but individual trajectories showed different behavior patterns amongst countries. Bayesian information creation showed that the 3-cluster model was the best choice. The annual growth of -0.13 (per 100,000 persons) suggests a slight negative trend for the incidence rate of breast cancer in cluster one countries, including Bangladesh, Israel, Kyrgyz Republic, Maldives, Nepal, North Korea, Tajikistan, and Timor-Leste. Seventeen countries, including Armenia, Bahrain, Brunei, Cyprus, Iraq, Japan, Jordan, Kazakhstan, Kuwait, Lebanon, Malaysia, Pakistan, Philippines, Qatar, Singapore, South Korea, and United Arab Emirates, which belonged to cluster 2 had not only a higher number of incidence rate in 1990, but also an annual growth of 0.96 (per 100,000 persons), indicating a sharp increase trajectory. Also, annual growth of 0.38 (per 100,000 persons) showed a slow increase in the incidence rate of breast cancer over time for the 21 remaining countries. Conclusion: The observed sharp increase of breast cancer incidence in Armenia, Bahrain, Brunei, Cyprus, Iraq, Japan, Jordan, Kazakhstan, Kuwait, Lebanon, Malaysia, Pakistan, Philippines, Qatar, Singapore, South Korea, and United Arab Emirates is remarkable; therefore, effective strategies to prevent it are urgently required
COVID-19 Pandemic is Not Over for Survivors with Long COVID Syndrome: Evidence of a One-Year Retrospective Follow-up Study from Iran
No full textBackground: Most patients who are infected by COVID-19 develop recovery from it; however, some of these patients experience a variety of mid-and long-term physical and/or mental effects after their initial illness recovery. These mid and long-term effects are collectively known as post-COVID-19 conditions or “long COVID.” Objectives: We aimed to detect the incidence of long COVID syndrome (LCS) and its determinants. Methods: In this retrospective cohort study, previously hospitalized subjects due to COVID-19 were selected by systematic random sampling. A valid checklist was filled out by phone interview with each participant, while hospitalization data were extracted from hospital information system. Data were analyzed using SPSS software. Results: The mean age of 1,738 interviewees was 54.2 ± 14.5 years. The median time of follow-up was 352 days. Overall, 1,526 (87.8%) interviewees had at least one symptom of LCS. Among physical symptoms, hair loss (23.9%) and among psychological complaints, depression (69.1%) were predominant. Anemia (odds ratio (OR): 3.22, 95% confidence interval (CI): 1.49-6.98), patients of second epidemic wave (OR: 2.82, 95% CI: 1.57-5.07), use of vitamins/minerals (OR: 2.25, 95% CI: 1.53-3.3) or antibiotics (OR: 1.84, 95% CI: 1.02-3.33), diabetes mellitus (OR: 1.9, 95% CI: 1.11-3.23), who were not the head of their families (OR: 1.65, 95% CI: 1.18-2.32) and use of antivirals (OR: 1.64, 95% CI: 1.03-2.61) were significantly associated with LCS. Conclusions: COVID-19 pandemic is not over, and most COVID-19 survivors suffer from LCS. Therefore, the establishment of integrated post-COVID care systems for these patients is highly needed and recommended
Study of the modulational instability and miscellaneous soliton for metamaterials via three powerful schemes
No full textIn this paper, the exact solitary wave solutions for the generalized nonlinear (NL) Schrödinger equation with parabolic NL law employing the generalized (G'/G)expansion technique, the improved tan(φ/2)-expansion technique and the modified exp-function technique are acquired. Different sets of exponential function solutions are acquired relying on a map between the considered equation and an auxiliary ordinary differential equation (ODE). The obtained solutions are concluded in several of the hyperbolic and trigonometric forms based on diverse restrictions between parameters involved in equations and integration constants that appear in the solution. A few significant ones among the reported solutions are pictured to perceive the physical utility and peculiarity of the considered model utilizing mathematical software. For more analysis, the modulation instability (MI) analysis of the proposed model with normal derivatives is also carried out for parabolic NL law. The main aim of this research is that one can visualize and update the knowledge to overcome from the most common methods to solve the ODEs and partial differential equations (PDEs). We demonstrated that these solutions validated the program using Maple and found them to be correct. The proposed methodology for resolving NLPDEs has been designed to be effectual, unpretentious, expedient, and manageable. Finally, the existence of the solutions for the constraint conditions is also shown
Enhancing the Antiviral Potential and Anti-inflammatory Properties of Astragalus membranaceus: A Comprehensive Review
No full textThe role of herbal medicines in the treatment of viruses and the identification of potential antiviral drugs has been the focus of researchers for decades. The control and treatment of viral diseases are very important due to the evolution of viruses and the emergence of new viruses compared to other pathogens such as fungi and bacteria. Astragalus membranaceus (AM) is a significant medicinal plant. The potential use of this plant and its chemical components in the treatment of inflammatory illnesses and viral diseases has been vigorously researched recently. Astragalus polysaccharides (APS) make up the majority of AM's ingredients. The main mechanisms of the antiviral effect of APS have been investigated in some studies. The results of these studies show that APS can exert its antiviral effect by enhancing type I IFN signaling, inhibiting the expression of Bax and Caspase-3 proteins in the apoptosis pathway, and other antiviral mechanisms such as anti-inflammatory activities. The most wellknown inflammatory products of APS's antiviral effects are B-cell proliferation, antibody products, nuclear factor-kappa B (NF-κB), and IL(s). Although it has a known effectiveness, there are some limitations to this substance's use as medicine. The use of nanotechnology is removing these limitations and its ability to be used as an anti-virus agent. The purpose of this review is to emphasize the role of AM, especially APS, in controlling inflammatory pathways in the treatment of viral infections. With the emergence of these herbal medications, a new path has been opened in the control and treatment of viral infections