Influence of different concentrations of two chemical chaperones on human islet amyloid polypeptide folding under experimental conditions

It has been implicated that type 2 diabetes mellitus is a conformational disease because amylin, a peptide produced by beta cell, undergoes an alteration in the native formation followed by self-aggregation and deposition. Amyloidogenesis causes destruction of pancreatic beta-cells. The subsequent lack of insulin leads to increased blood glucose. The main aim of this study was to investigate whether two chemical chaperones named glycerol and spermine vary islet amyloid polypeptide folding under near-physiological circumstances. For this purpose, fluorescent method was used with LS55 spectrofluorometer instrument. Results obtained from in vitro study show that after 240 h incubation by shaker incubator in 37°C, glycerol had contradictory effects on amylin folding and these effects were glycerol concentration dependent. Glycerol with concentration of 24% had the most inhibitory effect but 40 to 50% promoted amylin misfolding significantly (p<0.05). The obtained data also demonstrate that spermine with concentrations of 40, 50 and 60 μM had stimulatory effects on formation of beta-amyloid sheet significantly (p<0.05). It is concluded that amylin misfolding and cytotoxicity to beta-cells might be glycerol dose-dependent in diabetic patients.Key words: Chemical chaperones, islet amyloid polypeptide, diabetes mellitus, conformational disease

The effect of density and stocking weight on growth rate and production of grey mullet (Mugil cephalus L.)

Around ten thousands fries of Striped grey mullet (Mugil cephalus) with average weight and length of 280 mg and 28.3 mm respectively, imported in March 2008 from Egypt. The wild fries collected from surrounding natural waters of Alexandria. They stocked in four earthen ponds (each with 2500 m2 ) located at the Gomishan shrimp educational centre at late march in 2008. At the first year of culture the densities were 5000 and 10000 individuals per hectare and each treatment with two replicates. At second year, densities changed with 2000 and 2500 individuals per hectares and each of the treatments divided fishes with average primary weights of 80 and 115 grams. They fed twice a day at 8 AM and 2 PM and the amount was 5-7 percents of the fish existent biomass in each ponds. After seven months culture period, the average weight and length of fish in treatment 5000 ind./hec. were 113.7 gr and 21.1 cm respectively and in treatment 10000 ind./hec. the average weight and length were 86.6 gr and 19.6 cm respectively. At first year the average survival rate in different treatments was 77 percent. The average FCR in treatments 5000 and 10000 ind./hec. were 3.4 and 3.9 respectively. At second years after six months culture the average weights in pond no. 9 (with primary weight 115 gr and density 2000 ind./hec) , pond no. 10 (with primary weight 80 gr and density 2000 ind./hec) , pond no. 11 (with primary weight 115 gr and density 2500 ind./hec) and pond no. 12 (with primary weight 80 gr and density 2500 ind./hec) calculated as 476.6 ,338.1, 366.5 and 440 gr respectively. The average survival rate and FCR were 93 % and 3.1 respectively

PIWI-interacting RNAs: New biomarkers for diagnosis and treatment of breast cancer

Cancer is one of the most important reasons of mortality in the world. However, there are several therapeutic platforms to treat patients who suffering from cancer common treatments such as surgery, chemotherapy and etc. The current therapeutic approaches are related to some limitations. Hence, more understanding about molecular mechanisms that involved in cancer particularly in breast cancer pathogenesis, could contribute to provide better therapeutic platforms. Recently, non-coding RNAs such as microRNAs have attracted researchers' attention in the field of cancer due to their functions in gene expression's regulation and functional interactions with other molecules. Interestingly, great advances in next-generation sequencing lead to considering other roles for another non-coding RNAs subgroup called PIWI-interacting RNAs (piRNAs) in addition to their functions in the germline. Novel studies investigated the role of piRNAs in several cancers including lung cancer, hepatocellular carcinoma, gastric cancer, multiple myeloma and colorectal cancer. Hopefully, based on new findings, piRNAs may be a potential biomarker which can be used as a tool to diagnose or treat breast cancer. Thus, this review aimed to discuss the role of piRNAs in breast cancer progression and metastasis as well as its molecular mechanisms. © 2020 The Author(s)

Evaluation of Different Types of Lasers in Surface Conditioning of Porcelains: A Review Article

To achieve proper bond strength for porcelains, adequate surface roughness is essential, which is traditionally gained by sandblasting or acid etching with hydrofluoric (HF) acid. Nowadays with the development of laser systems, serious efforts were made to apply this new instrument for surface etching of porcelains due to easy usage, safety, and more efficiency. There are different kinds of lasers and porcelains, so choosing the ones which will be good match for each other is crucial. Besides that, changing the irradiation setting can be beneficial as well. This article reviewed 33 related studies and summarized results of etching accomplished by Nd:YAG, Er:YAG, Er,Cr:YSGG and CO2 lasers on different types of porcelains considering different laser settings and evaluation methods to bring a comprehensive insight

Efficacy of Photobiomodulation Therapy for Orthodontic Pain Control Following the Placement of Elastomeric Separators: A Randomized Clinical Trial

Introduction: Controlling pain in orthodontic patients has gained special attention. This study assessed the efficacy of photobiomodulation therapy (PBMT) for pain control following the placement of elastomeric separators.Methods: This split-mouth single-blind randomized clinical trial evaluated 30 orthodontic patients who required posterior elastomeric separators. The two maxillary quadrants were randomized into the laser and control groups. In the laser quadrant, an 808 nm diode laser (400 mW, 15.60 J/cm2,11 seconds, continuous-wave, contact mode) was irradiated to the cervical third of the maxillary first molar roots 24 hours prior to the placement of separators. The control quadrant received placebo radiation by a light-curing unit. The patients received the second laser cycle right before the placement of separators 24 hours later. The level of self-perceived pain was recorded at 0, 2, 6, 24, and 72 hours and 5 days after the intervention in the laser and control quadrants using a visual analog scale (VAS). Data were analyzed using the analysis of variance (ANOVA) and paired-samples t-test.Results: The trend of change in the pain score was similar in both groups. The pain score was significantly lower in the laser group than the control group at all-time points (P<0.05) except at time 0. The pain score increased in the first 6 hours and reached its maximum level in 24 hours in both groups.Conclusion: PBMT by an 808 nm diode laser can effectively decrease pain following the placement of elastomeric separators DOI:10.34172/jlms.2021.0

Finite Element Reconstruction of a Mandibular First Molar

Introduction: Mandibular first molar is the most important tooth with complicated morphology. In finite element (FE) studies, investigators usually prefer to model anterior teeth with a simple and single straight root; it makes the results deviate from the actual case. The most complicated and time-consuming step in FE studies is modeling of the desired tooth, thus this study was performed to establish a finite element method (FEM) of reconstructing a mandibular first molar with the greatest precision. Materials and Methods: An extracted mandibular first molar was digitized, and then radiographed from different aspects to achieve its outer and inner morphology. The solid model of tooth and root canals were constructed according to this data as well as the anatomy of mandibular first molar described in the literature. Result: A three-dimensional model of mandibular first molar was created, giving special consideration to shape and root canal system dimensions. Conclusion: This model may constitute a basis for investigating the effect of different clinical situations on mandibular first molars in vitro, especially on its root canal system. The method described here seems feasible and reasonably precise foundation for investigations

Research Paper: Effectiveness of Corticosteroid Therapy for Caustic Esophageal Injury

Background: Delayed caustic injury complications are common, especially in developing countries, and several treatments have been proposed to prevent the resulting esophageal strictures so far. Although inflammatory nature of caustic injury makes the anti-inflammatory agents a viable option, few studies have investigated these agents. High-dose corticosteroids therapy for reduction of stricture formation in the esophagus after the ingestion of caustic material is still a controversial topic. In this regard, this study aimed to determine the impact of high doses of methylprednisolone in preventing esophageal stricture.Methods: A total of 112 patients with grade II esophageal caustic injury, diagnosed by esophagogastroscopy within 24 hours of injury, were enrolled in our study. The treatment group (n=44) received methylprednisolone (1 g/d for 3 days), pantoprazole, ceftriaxone, and metronidazole and the control group (n=58) received the same regimen excluding methylprednisolone. Endoscopic and radiologic findings were used to compare the severity of the damage to the esophagus and stomach between the two groups.Results: After 8 months of follow-up, stricture development was observed in 3 (5.6%) patients in the treatment group and in 11 (19%) patients in the control group. The difference was statistically significant (P=0.038). The gastric outlet obstruction was observed in 4 (7.4%) patients in the treatment group and in 19 (32.7%) patients in the control group. Again, the difference was statistically significant (P<0.05). There were not any side effects due to the high doses of methylprednisolone in the study group.Conclusion: High doses of methylprednisolone can prevent the development of esophageal stricture in grade II of caustic injury

Comparison of social values in health priority setting: the experiences of seven countries

Background: Priority setting is a key function to optimize the allocation of limited healthcare resources. Technical and judgmental criteria are used in priority setting decisions. The present study aims to compare the social values in some countries’ health care system based on Clark-Weale framework.  Methods: We searched the PubMed and Scopus to find published studies on the role of social values in priority setting based on the Clark-Weale framework. We checked references in order to include landmark papers which were not found in the previous step. On the basis of this framework, we subsequently compared content and process values based on which priorities are set in identified studies.    Results: Our review showed that this framework is applied to describe social values in priority setting in Australia, England, China, Germany, Iran, Republic of Korea, Thailand, Latin American countries, and USA. Countries apply the social values in different ways. Some of them consider an extended range of values and some use only a limited number of values. Content values are often more reliable than process values. Contextual characteristics and having committees in operation to advise priority setting tasks had significant roles in taking social values into consideration in the process of health priority setting.  Conclusion: It is difficult to examine how exactly health priority setting decisions are influenced by social values in health systems. However, a comparative picture of values and their relative importance can contribute to understand the status quo and under-represented values