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Synthesis and characterization of thermosensitive hydrogel based on quaternized chitosan for intranasal delivery of insulin
No full textNasal administration is a form of systemic administration in which drugs are insufflated through the nasal cavity. Steroids, nicotine replacement, antimigraine drugs, and peptide drugs are examples of the available systematically active drugs as nasal sprays. For diabetic patients who need to use insulin daily, the nasal pathway can be used as an alternative to subcutaneous injection. In this regard, intranasal insulin delivery as a user-friendly and systemic administration has recently attracted more attention. In this study, a novel formulation consists of chitosan, chitosan quaternary ammonium salt (HTCC), and gelatin (Gel) was proposed and examined as a feasible carrier for intranasal insulin administration. First, the optimization of the chitosan�HTCC hydrogel combination has done. Afterward, Gel with various amounts blended with the chitosan�HTCC optimized samples. In the next step, swelling rate, gelation time, degradation, adhesion, and other mechanical, chemical, and biological properties of the hydrogels were studied. Finally, insulin in clinical formulation and dosage was blended with optimized thermosensitive hydrogel and the release procedure of insulin was studied with electrochemiluminescence technique. The optimal formulation (consisted of 2 wt chitosan, 1 wt HTCC, and 0.5 wt Gel) showed low gelation time, uniform pore structure, and the desirable swelling rate, which were resulted in the adequate encapsulation and prolonged release of insulin in 24 H. The optimal samples released 65 of the total amount of insulin in the first 24 H, which is favorable for this study. © 2020 International Union of Biochemistry and Molecular Biology, Inc
Acute traumatic sequestrated thoracic disc herniation: A case report and review
Get PDFBackground: Pure sequestrated thoracic disc herniations secondary to a traumatic event are rare. Case Description: Elderly male presented with the sudden onset of severe paraparesis following a fall. The MR showed a left-sided extruded disc at the T10-T11. The patient underwent a thoracic interlaminar laminectomy, removal of one large, and several smaller sequestrated disc fragments utilizing a transfacet corridor requiring placement of an interbody Peek cage, and bilateral T10 and T11 pedicle screw instrumentation. At 6 postoperative months, he sustained a good recovery. Conclusion: Acute thoracic disc herniations without attendant fracture/dislocation are rare. When they result in major neurological deficits, timely surgical excision is warranted. © 2021 Published by Scientific Scholar on behalf of Surgical Neurology International
Genetic testing of leukodystrophies unraveling extensive heterogeneity in a large cohort and report of five common diseases and 38 novel variants
Get PDFThis study evaluates the genetic spectrum of leukodystrophies and leukoencephalopathies in Iran. 152 children, aged from 1 day to 15 years, were genetically tested for leukodystrophies and leukoencephalopathies based on clinical and neuroradiological findings from 2016 to 2019. Patients with a suggestive specific leukodystrophy, e. g. metachromatic leukodystrophy, Canavan disease, Tay-Sachs disease were tested for mutations in single genes (108; 71) while patients with less suggestive findings were evaluated by NGS. 108 of 152(71) had MRI patterns and clinical findings suggestive of a known leukodystrophy. In total, 114(75) affected individuals had (likely) pathogenic variants which included 38 novel variants. 35 different types of leukodystrophies and genetic leukoencephalopathies were identified. The more common identified disorders included metachromatic leukodystrophy (19 of 152; 13), Canavan disease (12; 8), Tay-Sachs disease (11; 7), megalencephalic leukodystrophy with subcortical cysts (7; 5), X-linked adrenoleukodystrophy (8; 5), Pelizaeus�Merzbacher-like disease type 1 (8; 5), Sandhoff disease (6; 4), Krabbe disease (5; 3), and vanishing white matter disease (4; 3). Whole exome sequencing (WES) revealed 90 leukodystrophies and genetic leukoencephalopathies. The total diagnosis rate was 75. This unique study presents a national genetic data of leukodystrophies; it may provide clues to the genetic pool of neighboring countries. Patients with clinical and neuroradiological evidence of a genetic leukoencephalopathy should undergo a genetic analysis to reach a definitive diagnosis. This will allow a diagnosis at earlier stages of the disease, reduce the burden of uncertainty and costs, and will provide the basis for genetic counseling and family planning. © 2021, The Author(s)
The effect of risk communication on preventive and protective Behaviours during the COVID-19 outbreak: mediating role of risk perception
Get PDFBackground: The COVID-19 outbreak is a global pandemic, during which the community preventive and protective behaviors play a crucial role in the containment and control of infection. This study was designed to contribute to the existing knowledge on how risk communication (RC) and risk perception (RP) affect protective and preventive behaviors (PPB) during the COVID-19 outbreak. Methods: The required data were extracted from a national online survey of Iranian adults aged 15 and older during March 15�19, 2020 (n=3213). Data analysis was performed using structural equation modeling. Results: The study findings reveal that RC has direct and indirect positive effects on PB. Furthermore, this study also provides new evidence indicating that RP mediates the relationship between RC and PB and there is a two-way relationship between RC and RP. These interactions may have impact on risk communication strategies which should be adopted during this pandemic. Conclusion: The study findings have remarkable implications for informing future communications as well as interventions during this ongoing outbreak and subsequent national risk events. © 2021, The Author(s)
Association between ratio for diameters of pulmonary artery to ascending aorta bifurcation in chest CT scan and number of involved vessels in coronary angiography
Get PDFObjective: Coronary artery disease (CAD) is an important cause of mortality and morbidity, therefore, recognizing its severity and related factors is important. This study was performed to evaluate the association between ratio for diameters of pulmonary artery to ascending aorta bifurcation in chest CT scan and number of involved vessels in coronary angiography. In this observational cross-sectional comparative study, 110 patients who were under coronary angiography in Firoozgar Hospital in 2017 were enrolled, and the association between ratio for diameters of pulmonary artery to ascending aorta bifurcation in their chest CT scan and number of involved vessels in angiography were assessed. Results: In this study, number of involved vessels in angiography was related to PA/Ao ratio (P = 0.001) and further vessels were accompanied with higher ratio. It may be concluded that, a higher ratio for diameters of pulmonary artery to ascending aorta bifurcation in chest CT scan is related to higher number of involved vessels in coronary angiography, and it may have a predictive role. © 2021, The Author(s)
Comparing various protocols of human and bovine ovarian tissue decellularization to prepare extracellular matrix-alginate scaffold for better follicle development in vitro
Get PDFBackground: Nowadays, the number of cancer survivors is significantly increasing as a result of efficient chemo/radio therapeutic treatments. Female cancer survivors may suffer from decreased fertility. In this regard, different fertility preservation techniques were developed. Artificial ovary is one of these methods suggested by several scientific groups. Decellularized ovarian cortex has been introduced as a scaffold in the field of human fertility preservation. This study was carried out to compare decellularization of the ovarian scaffold by various protocols and evaluate the follicle survival in extracellular matrix (ECM)-alginate scaffold. Results: The micrographs of H&E and DAPI staining confirmed successful decellularization of the ovarian cortex in all experimental groups, but residual DNA content in SDS-Triton group was significantly higher than other groups (P < 0.05). SEM images demonstrated that complex fiber network and porosity structure were maintained in all groups. Furthermore, elastin and collagen fibers were observed in all groups after decellularization process. MTT test revealed higher cytobiocompatibility of the SDS-Triton-Ammonium and SDS-Triton decellularized scaffolds compared with SDS groups. Compared to the transferred follicles into the sodium alginate (81), 85.9 of the transferred follicles into the decellularized scaffold were viable after 7 days of cultivation (P = 0.04). Conclusion: Although all the decellularization procedures was effective in removal of cells from ovarian cortex, SDS-Triton-Ammonium group showed less residual DNA content with higher cytobiocompatibility for follicles when compared with other groups. In addition, the scaffold made from ovarian tissues decellularized using SDS-Triton-Ammonium and sodium alginate is suggested as a potential 3D substrate for in vitro culture of follicles for fertility preservation. © 2021, The Author(s)
Bland-Altman methods for comparing methods of measurement and response to criticisms
Get PDFIntroduced in 1983, Bland-Altman methods is now considered the standard approach for assessment of agreement between two methods of measurement. The method is widely used by researchers in various disciplines so that the Bland-Altman 1986 Lancet paper has been named as the 29th mostly highly cited paper ever, over all fields. However, two papers by Hopkins (2004) and Krouwer (2007) questioned the validity of the Bland-Altman analysis. We review the points of critical papers and provide responses to them. The discussions in the critical papers of the Bland-Altman method are scientifically delusive. Hopkins misused the Bland-Altman methodology for research question of model validation and also incorrectly used least-square regression when there is measurement error in the predictor. The problem with Krouwers' paper is making sweeping generalisation of a very narrow and somewhat unrealistic situation. The method proposed by Bland and Altman should be used when the research question is method comparison. © 202
Assessment of littered cigarette butt in urban environment, using of new cigarette butt pollution index (CBPI)
No full textCigarette butts (CBs) are hazardous wastes usually littered by smokers and are of the prevalence wastes in the environment. Although various studies have been done regarding the quantity of CBs on the coast, few studies have been conducted on its density and distribution in urban areas. Therefore, the objective of this study was to assess the quantity and distribution of CBs in urban areas to define an index to convert the results into comparable data in various conditions and cities. The data were obtained by visual surveys using field CB counts in the summer of 2019 in the city of Qazvin, Iran. Cigarette butt pollution index (CBPI) was defined by considering CB density, weather conditions, urban characteristics including the structure of the walkways, and distance from groundwater. The findings indicated that the average cigarette butts density in urban areas were found to be in range of 0.01 and 0.51. Spatial variation of CB was observed in the city due to urban characteristics like land use, differences in municipal services, and population density. The CBPI index calculated for a park showed the highest number whereas an administrative (official) area had the lowest CBPI of 0.15. Given the significant pollution of the city studied with CBs and the proper performance of CBPI in classifying various parts of the city, using this method and index can be a good way to assess CBs in the streets of most of the cities. © 2020 Elsevier B.V
Cinnamon extract loaded electrospun chitosan/gelatin membrane with antibacterial activity
No full textThis study develops chitosan/gelatin nanofiber membranes with sustained release capacity to prevent infection by delivering cinnamon extract (CE) in the implanted site. The effects of the incorporation of CE content (2�6) on the properties of the nanofibers were evaluated. Morphological studies using SEM indicated that loading the extract did not affect the average diameter of nanofiber mats, which remained around 140�170 nm. TGA and FTIR spectroscopy results confirmed successful CE loading. Furthermore, the results showed that incorporating extract into the nanofibers enhanced their degradation behavior, antibacterial activity, and biocompatibility. Cultured cells attached to and proliferate on the nanofiber membrane with high cell viability capacity until the CE content reached 4. The extract release profile consisted of a burst release in the first 6 h, followed by a controlled release in the next 138 h. Therefore, CE loaded chitosan/gelatin nanofiber is an excellent construct for biomedical applications. © 2021 Elsevier B.V
Impact of anticholinergic drugs withdrawal on motor function in patients with Parkinson's disease
No full textObjectives: Physicians have prescribed anticholinergic agents as monotherapy or adjuvant therapy in patients with Parkinson's disease for decades. However, these medications can cause many adverse effects including gait freezing and falling. Herein we assessed the effects of anticholinergic medications on motor function, freezing of gait and falling in a group of patients with PD. Patients and Methods: This prospective study evaluated the effect of gradual discontinuation of anticholinergics on motor function in 131 outpatients with Parkinson's disease. We assessed patients� motor function at baseline six and twelve months later using the UPDRS-III. We also evaluated freezing of gait and falling in patients using UPDRS-II part 14 and 13 respectively. The anticholinergics were tapered and gradually discontinued and additional levodopa doses were added as patients needed. Results: 131patients successfully discontinued their anticholinergic medications. Stopping anticholinergics significantly improved the motor symptoms in PD patients as reflected in the change between the mean (±SD) UPDRS-III score of 36.85(±11.5) at the baseline to 32.51(±11.4) and 31.43 (±11.3) after six and twelve months (P < 0.001). The mean (±SD) scores of freezing of gait (FOG)significantly changed from 1.34(±1) to 1.17(±1) and 0.6(±0.7) and for falling down from 0.62(±0.8) to 0.5 (±0.8) and 0.29(±0.5) respectively (p-value of <0.001). Conclusion: Our finding demonstrated an improvement in motor function and FOG and falling incidences in PD patients, after discontinuation of anticholinergic drugs. As motor complications adversely affect the quality of life in PD patients, clinicians must be careful with the unnecessary use of anticholinergic drugs in their treatment strategies. © 202