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1.
Protein Pept Lett ; 29(1): 80-88, 2022.
Article in English | MEDLINE | ID: mdl-34825860

ABSTRACT

BACKGROUND: Due to their solid-like porous structure, molecular organogel and microcrystal structures have the capabilities of loading drug molecules, encapsulation, and extended release, all considered as essential properties in drug delivery applications. Phases of these structures, however, depend on the solvent used during the gelation process. OBJECTIVE: Understanding the phase transition between organogel and microcrystal structures through adjusting the mixture ratio of different co-solvents. METHODS: Short peptide Diphenylalanine as the gelation building block was used due to its amino acid sequences that can be exactly selected at its molecular levels. Ethanol as a polar solvent was used in combination with four other co-solvents with different polarity levels, namely Xylene, Toluene, Acetone, and Dimethyl Sulfoxide. The morphology of molecular structures of each co-solvent combination at each ratio level was examined as well as the loading and release properties for a non-polar Flufenamic Acid drug. RESULTS: The resultant structure was affected by the polarity of the co-solvents; in particular, in the sample containing 25 µg/ml of the drug, 94% of the drug amount was loaded inside the organogel. By increasing the drug concentration to 50, 75, and 100 µg/ml, the loading capability decreased to 76%, 47%, and 33%, respectively. CONCLUSION: Molecular organogels have excellent capabilities of loading drug molecules, while microcrystal structures have higher release capacity. The findings of this study reveal how to best design a gelation method to obtain maximum loading or release properties for a particular peptide- based drug delivery application.


Subject(s)
Drug Delivery Systems , Peptides , Phenylalanine , Solvents/chemistry
2.
J Res Health Sci ; 17(4): e00395, 2017 Oct 14.
Article in English | MEDLINE | ID: mdl-29233952

ABSTRACT

BACKGROUND: The estimate of mortality associated with illicit opiate use provides useful information to those directing and monitoring local, national and international policies and programs. This study investigated the epidemiology of mortality due to the illegal consumption of narcotics and psychotropic substances in the Iran to provide evidence-based public health data for useful programs and actions aimed at preventing drug-related mortality. STUDY DESIGN: A cross-sectional study. METHODS: The information regarding all cases of psychotropic positive was collected from Legal Medicine Organization, occurred on Mar 2015 to Feb 2016. Demographic and epidemiological data were extracted from recorded documents. Data were then analyzed in Stata software. RESULTS: Overall, 2306 died cases from opioid or psychotropic abuse were evaluated. The mean age of the subjects was 36.07±12.61 yr, they were mostly single male, and 88.64% of them had Iranian nationality. The mortality rate from opiate and psychotropic abuse in the whole country was 38.22 per 1000000 population. The most common location of death was at home or in another private residence. History of overdose, suicide, hospitalization in psychiatric hospital, staying in prison and substance abuse in the family observed in some people who died from drug abuse. CONCLUSIONS: Mortality rate from substance abuse is more among unmarried young men aged 30-39 yr with low education level also in self-employed. We suggest policies to prevent this person accessing and using drug.


Subject(s)
Illicit Drugs , Narcotics , Psychotropic Drugs , Substance-Related Disorders/mortality , Adolescent , Adult , Age Factors , Aged , Aged, 80 and over , Child , Child, Preschool , Cross-Sectional Studies , Epidemiologic Studies , Female , Humans , Infant , Infant, Newborn , Iran/epidemiology , Male , Middle Aged , Opioid-Related Disorders/mortality , Sex Factors , Socioeconomic Factors , Young Adult
3.
Int Ophthalmol ; 37(4): 965-971, 2017 Aug.
Article in English | MEDLINE | ID: mdl-27671494

ABSTRACT

PURPOSE: The purpose of the study was to assess the agreement of anterior segment optical coherence tomography with its older well-known opponent i.e., Sheimpflug imaging in evaluation of the cornea in normal and keratoconus subjects. METHODS: 107 normal and 56 keratoconus eyes were evaluated with the anterior segment optical coherence tomography followed by the Scheimpflug imaging. Parameters included axial keratometry data in both of steep and flat meridians, mean keratometry and the astigmatism values in the central 4.0 mm zone, central, thinnest and apex corneal thicknesses, Q-value in 8 mm zone and pupil diameter. Corneal topographic maps were recorded and were evaluated for anterior highest and lowest points, posterior highest and lowest points. Average values were recorded for analysis. RESULTS: All anterior cornea keratometry indices showed perfect agreement between two devices in normal corneas; while the level of agreement in keratoconus cases ranged from moderate to strong. All posterior keratometry indices also showed perfect agreement in both groups; except for flat K in normal corneas and steep K in KC ones. The amount of corneal cylinder in normal corneas had perfect agreement, and moderate to strong agreement in anterior/posterior cornea in keratoconus group. Anterior highest and lowest points showed strong and perfect agreement in normal and keratoconus cases, respectively. Posterior highest and lowest points showed strong agreement in normal cases. Thickness indices (central, thinnest, and apex thicknesses) showed perfect agreement between two devices in both normal and KC groups. Mean values of anterior and posterior highest points were statistically higher in Scheimpflug system. CONCLUSIONS: Although two imaging technologies had statistically numerical different output, it seems that they have a good agreement in most parameters.


Subject(s)
Astigmatism/diagnosis , Cornea/pathology , Corneal Topography/methods , Keratoconus/diagnosis , Tomography, Optical Coherence/methods , Adult , Astigmatism/etiology , Cross-Sectional Studies , Female , Humans , Keratoconus/complications , Male , ROC Curve , Reproducibility of Results
4.
Adv Biomed Res ; 5: 39, 2016.
Article in English | MEDLINE | ID: mdl-27099852

ABSTRACT

BACKGROUND: Corneal transplantation is a surgery in which cornea is replaced by a donated one and can be completely penetrating keratoplasty (PK) or included a part of cornea deep lamellar keratoplasty (DLK). Although the functional results are limited by some complications, it is considered as one of the most successful surgeries. This study aimed to compare the refractive errors after same size corneal transplantation through DLK and PK methods in keratoconus patients over 20 years. MATERIALS AND METHODS: This descriptive, analytical study was conducted in Feiz Hospital, Sadra and Persian Clinics of Isfahan in 2013-2014. In this study, 35 patients underwent corneal transplantation by PK and 35 patients by DLK, after removing the sutures, the patients were compared in terms of best corrected visual acuity (BCVA) and refractive errors. Data were analyzed using Chi-square and t Student tests by SPSS software. RESULTS: The BCVA mean in DLK and PK groups was 6/10 ± 2/10 and 5/10 ± 2/10, respectively, with no significant difference (P = 0.4). The results showed 9 cases of DLK and 6 cases of PK had normal (8/10 ≤ BCVA) visual acuity (25.7% vs. 17.1%), 24 cases of DLK and 27 cases of PK had mild vision impairment (68.6% vs. 77.1%) and 2 cases of the DLK group and 2 cases of PK had moderate vision impairment, (5.7% vs. 5.7%), there was no significant difference in "BCVA" (P = 0.83). CONCLUSIONS: Both methods were acceptably effective in improving BCVA, but according to previous articles (5,9,10) the DLK method due to fewer complications and less risk of rejection was superior to another method and in the absence of any prohibition this method is recommended.

5.
Adv Biomed Res ; 4: 52, 2015.
Article in English | MEDLINE | ID: mdl-25802821

ABSTRACT

BACKGROUND: To report the long-term findings of corneal cross-linking (CXL) with riboflavin drops on the corneal endothelial cell. MATERIALS AND METHODS: In this prospective non-randomized study, we aim to assess the long-term safety of CXL on the corneal endothelium for the treatment of progressive keratoconus, by endothelial specular microscopy. A total of 68 eyes of 42 keratoconus patients were selected. We checked the corneal thickness (with ultrasonic pachymetry), endothelial cell density, pleomorphism, and polymegathism (with specular microscopy) of the endothelial cells, before CXL and one year after this procedure. RESULTS: The mean ± SD of the preoperative and postoperative corneal thicknesses were 470 ± 40 µm and 469.8 ± 42 µm, respectively (p-value = 0.591). The mean ± SD of the preoperative and postoperative endothelial cell densities were 2753 ± 230 cells/mm[2] and 2699 ± 210 cells/mm,[2] respectively (p-value = 0.004). We found reduction in the endothelial cell density after CXL, but this reduction was less significant in a corneal thickness of less than 400 µm (which was treated with hypo-osmolar riboflavin 0.1% drops) compared to the corneal thickness of more than 450 µm. We did not find any significant differences in the cell shapes (pleomorphism) (p-value = 0.517), but the cell sizes (polymegathism) were changed after the procedure (p-value = 0.021). CONCLUSION: We found a significant decrease in endothelial corneal cell density after CXL, but this reduction was low; also the size of these cells increased after CXL. We believe that other parameters besides the corneal thickness may be the determinant factors for the changing of cell density and cell size in corneal endothelial cells.

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