43 research outputs found

    Corneal biomechanical properties distribution in myopic population

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    AIM: To evaluate distribution of corneal biomechanical measurements in normal myopia and myopic-astigmatism population.<p>METHODS:One hundred and eighty eyes with myopia and myopic-astigmatism candidated for laser refractive surgery were included in this study. Complete examination of anterior and posterior segments, manifest refraction spherical equivalent(MRSE), Orbscan and Zywave were performed preoperatively. Ocular response analyzer(ORA)was used to measure corneal hysteresis(CH), corneal resistance factor(CRF), Goldmann-correlated intraocular pressure(IOPg)and corneal compensated IOP(IOPcc). Distribution of all corneal biomechanical properties and correlation between these parameters and MRSE, age and sex were determined. Statistical analysis was performed using SPSS 17 software and a <i>P</i>-Value less than 0.05 was considered significant. <p>RESULTS: Mean age was 28.20±6.78 years. Mean MRSE was -4.21±1.19D. Mean CH, CRF, IOPg and IOPcc was 10.00±1.28mmHg, 10.17±1.45mmHg, 15.71±2.67mmHg and 16.68±2.41mmHg respectively. 28.4% of all myopic population had CH about 10mmHg, and 71% had CH, 9mmHg up to 11mmHg. CRF in 25.9% of myopic population was 10mmHg, and in 48.7% was 9mmHg up to 11mmHg. There was very poor positive correlation between MRSE& CH(Rs=0.001, <i>P</i>=0.71)and MRSE& CRF(Rs=0.01, <i>P</i>=0.18).<p>CONCLUSION: Our study demonstrated the distribution of corneal biomechanical properties(CH, CRF, IOPg, IOPcc)in normal myopia and myopic-astigmatism population in Iran, and confirmed that, there was no statistically significant correlation between CH, CRF and MRSE, age and sex but there was significant correlation between IOPg, IOPcc and formerly mentioned parameters

    Corneal collagen cross-linking effects on pseudophakic bullous keratopathy

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    AIM: To evaluate the efficacy of riboflavin administration and ultraviolet A(UVA)cross-linking on advanced symptomatic bullous keratopathy. <p>METHODS: Fifteen patients with symptomatic pseudophakic bullous keratopathy(PBK)were included. Slit-lamp examination, visual acuity, foreign body sensation(FBS)questionnaire, corneal clarity grading, ocular pain intensity scale and corneal thickness measures with Pentacam and ultrasound pachymetry(UP), were performed before corneal cross-linking and 1 and 6mo thereafter. After using sodium chloride solution, for one week, the central 8mm(diameter)of the corneal epithelium was removed, and cross-linking, with riboflavin instillation every 3min for 30min, and UVA irradiation for 30min was performed. <p>RESULTS: Five males and 10 females with mean age of 66±13y were included. Mean follow up time was 6.2mo. Corneal transparency in all eyes was statistically significantly better 1 month after treatment than preoperatively(<i>P</i><0.05). At 6mo, however, corneal transparency was better in 8 eyes, the same in 5 eyes, and worse in 2 eyes compared with preoperative levels(<i>P</i>= 0.218). Foreign body sensation subsided in 70% of patients. The average CCT decreased within 1mo after the procedure(<i>P</i><0.05). At 6mo, all but 3 eyes had progressive swelling, and the CCT increased; however, the CCT was still statistically significantly thinner than preoperatively(<i>P</i>=0.006). The improvement in mean CDVA from preoperatively to 1mo postoperatively was statistically significant(<i>P</i>=0.010). At 6mo, no significant differences were observed(<i>P</i>=0.130). The pain scores at 1mo were statistically significantly better than preoperatively(<i>P</i>=0.007). At 6mo, however the mean pain score was higher than at 1mo and not statistically significantly different from the preoperative score(<i>P</i>=0.070). <p>CONCLUSION: Corneal CXL significantly improved corneal transparency, corneal thickness, and ocular pain 1 month postoperatively. However, it did not seem to have a long-lasting effect in decreasing pain and maintaining corneal transparency in patients with PBK. This procedure extends the time interval for corneal transplantation and increases visualization at DSAEK procedure

    Designing Authority Data Properties Based on Microdata Method and Study of Web Search Engines’ Reaction to Them

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    Objective: The purpose of this research was to study the Search Engine’s responses to authority data properties embedded into schema.org-based metadata on the Microdata syntax. Methods: The experimental method was used in this research. The research population comprised 400 records of authority metadata based on the Microdata method from the digital library of Allameh Tabataba'i University. The examination group consisted of 200 metadata records, 100 records with authority data extensions embedded into schema.org-based metadata in the Microdata syntax and 100 other similar records in the JSON-LD syntax (50 samples of name authority, and 50 other subject authority) And the control group consisted of 200 Records, including 100 Records related to the description of the book in the Microdata syntax and 100 other similar records in the JSON-LD syntax. The records have been published on the independent website at www.Aghadeh.ir and have been introduced to the Google, Bing, Yahoo, and Yandex search engines as designers of the schema.org standard. Then, through searching the search engines, using the data gathering tool, the checklist provided by the researchers, the indexing and retrieval of the metadata records of the control groups and experimental groups were evaluated in the search results of the selected search engines. Results: The results of this study showed that search engines were able to index and retrieve all of the metadata records and values of added extensions associated with authority data. Such a possibility had the same status for the name authority records and the subject authority data. Conclusions: By retrieving each of the variant properties’ values of examination group’s records, in addition to the authorized values of the name and subject terms, a suitable platform for the comprehensiveness of the retrieve process, and the authority control in the Web search tools will be improved

    Sensitivity to Antibiotics of Bacteria Exposed to Gamma Radiation Emitted from Hot Soils of the High Background Radiation Areas of Ramsar, Northern Iran

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    Background: Over the past several years our laboratories have investigated different aspects of the challenging issue of the alterations in bacterial susceptibility to antibiotics induced by physical stresses. Objective: To explore the bacterial susceptibility to antibiotics in samples of Salmonella enterica subsp. enterica serovar Typhimurium (S. typhimurium), Staphylococcus aureus, and Klebsiella pneumoniae after exposure to gamma radiation emitted from the soil samples taken from the high background radiation areas of Ramsar, northern Iran. Methods: Standard Kirby-Bauer test, which evaluates the size of the zone of inhibition as an indicator of the susceptibility of different bacteria to antibiotics, was used in this study. Results: The maximum alteration of the diameter of inhibition zone was found for K. pneumoniae when tested for ciprofloxacin. In this case, the mean diameter of no growth zone in non-irradiated control samples of K. pneumoniae was 20.3 (SD 0.6) mm; it was 14.7 (SD 0.6) mm in irradiated samples. On the other hand, the minimum changes in the diameter of inhibition zone were found for S. typhimurium and S. aureus when these bacteria were tested for nitrofurantoin and cephalexin, respectively. Conclusion: Gamma rays were capable of making significant alterations in bacterial susceptibility to antibiotics. It can be hypothesized that high levels of natural background radiation can induce adaptive phenomena that help microorganisms better cope with lethal effects of antibiotics

    BIOTECHNOLOGICAL PRODUCTS AND PROCESS ENGINEERING EGFP reporter protein: its immunogenicity in Leishmania-infected BALB/c mice

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    Abstract Optical reporter genes such as green fluorescent protein (GFP) and luciferase are efficiently and widely used in monitoring and studying the protective/therapeutic potential of candidate agents in leishmaniasis. But several observations and controversial reports have generated a main concern, whether enhanced GFP (EGFP) affects immune response. To address this issue, we studied the immunogenicity of EGFP in vivo by two lines of stably transfected parasites (Leishmania major EGFP or L. major EGFP-LUC ) in BALB/c model and/or as a recombinant protein (rEGFP) produced in vitro by bacteria in parallel. Disease progression was followed by footpad swelling measurements and parasite burden in draining lymph nodes using microtitration assay and real-time PCR, and immune responses were also evaluated in spleen. EGFP-expressing parasites generated larger swellings in comparison with wild-type (L. major) while mice immunized with rEGFP and challenged with wild-type parasite were quite comparable in footpad swelling with control group without significant difference. However, both conventional and molecular approaches revealed no significant difference in parasite load between different groups. More importantly, no significant inflammatory responses were detected in groups with higher swelling size measured by interferon-γ (IFN-γ), interleukin (IL)-10, IL-5, and nitric oxide against frozen and thawed lysate of parasite as stimulator. Altogether, these results clearly revealed that EGFP protein expressed in prokaryotic and eukaryotic hosts is not an immunological reactive molecule and acts as a neutral protein without any side effects in mice. So, EGFP expressing Leishmania could be a safe and reliable substitution for wildtypes that simplifies in situ follow-up and eliminates the animal scarification wherever needed during the study

    Effects of home confinement on mental health and lifestyle behaviours during the COVID-19 outbreak:insights from the ECLB-COVID19 multicentre study

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    Although recognised as effective measures to curb the spread of the COVID-19 outbreak, social distancing and self-isolation have been suggested to generate a burden throughout the population. To provide scientific data to help identify risk factors for the psychosocial strain during the COVID-19 outbreak, an international cross-disciplinary online survey was circulated in April 2020. This report outlines the mental, emotional and behavioural consequences of COVID-19 home confinement. The ECLB-COVID19 electronic survey was designed by a steering group of multidisciplinary scientists, following a structured review of the literature. The survey was uploaded and shared on the Google online survey platform and was promoted by thirty-five research organizations from Europe, North Africa, Western Asia and the Americas. Questions were presented in a differential format with questions related to responses “before” and “during” the confinement period. 1047 replies (54% women) from Western Asia (36%), North Africa (40%), Europe (21%) and other continents (3%) were analysed. The COVID-19 home confinement evoked a negative effect on mental wellbeing and emotional status (P < 0.001; 0.43 ≤ d ≤ 0.65) with a greater proportion of individuals experiencing psychosocial and emotional disorders (+10% to +16.5%). These psychosocial tolls were associated with unhealthy lifestyle behaviours with a greater proportion of individuals experiencing (i) physical (+15.2%) and social (+71.2%) inactivity, (ii) poor sleep quality (+12.8%), (iii) unhealthy diet behaviours (+10%), and (iv) unemployment (6%). Conversely, participants demonstrated a greater use (+15%) of technology during the confinement period. These findings elucidate the risk of psychosocial strain during the COVID-19 home confinement period and provide a clear remit for the urgent implementation of technology-based intervention to foster an Active and Healthy Confinement Lifestyle AHCL)

    Globally altered sleep patterns and physical activity levels by confinement in 5056 individuals:ECLB COVID-19 international online survey

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    Symptoms of psychological distress and disorder have been widely reported in people under quarantine during the COVID-19 pandemic; in addition to severe disruption of peoples' daily activity and sleep patterns. This study investigates the association between physical-activity levels and sleep patterns in quarantined individuals. An international Google online survey was launched in April 6th, 2020 for 12-weeks. Forty-one research organizations from Europe, North-Africa, Western-Asia, and the Americas promoted the survey through their networks to the general society, which was made available in 14 languages. The survey was presented in a differential format with questions related to responses "before" and "during" the confinement period. Participants responded to the Pittsburgh Sleep Quality Index (PSQI) questionnaire and the short form of the International Physical Activity Questionnaire. 5056 replies (59.4% female), from Europe (46.4%), Western-Asia (25.4%), America (14.8%) and North-Africa (13.3%) were analysed. The COVID-19 home confinement led to impaired sleep quality, as evidenced by the increase in the global PSQI score (4.37 +/- 2.71 before home confinement vs. 5.32 +/- 3.23 during home confinement) (p &lt; 0.001). The frequency of individuals experiencing a good sleep decreased from 61% (n = 3063) before home confinement to 48% (n = 2405) during home confinement with highly active individuals experienced better sleep quality (p &lt; 0.001) in both conditions. Time spent engaged in all physical-activity and the metabolic equivalent of task in each physical-activity category (i.e., vigorous, moderate, walking) decreased significantly during COVID-19 home confinement (p &lt; 0.001). The number of hours of daily-sitting increased by similar to 2 hours/days during home confinement (p &lt; 0.001). COVID-19 home confinement resulted in significantly negative alterations in sleep patterns and physical-activity levels. To maintain health during home confinement, physical-activity promotion and sleep hygiene education and support are strongly warranted.</p

    Sleep Quality and Physical Activity as Predictors of Mental Wellbeing Variance in Older Adults during COVID-19 Lockdown:ECLB COVID-19 International Online Survey

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    Background. The COVID-19 lockdown could engender disruption to lifestyle behaviors, thus impairing mental wellbeing in the general population. This study investigated whether sociodemographic variables, changes in physical activity, and sleep quality from pre- to during lockdown were predictors of change in mental wellbeing in quarantined older adults. Methods. A 12-week international online survey was launched in 14 languages on 6 April 2020. Forty-one research institutions from Europe, Western-Asia, North-Africa, and the Americas, promoted the survey. The survey was presented in a differential format with questions related to responses "pre" and "during" the lockdown period. Participants responded to the Short Warwick-Edinburgh Mental Wellbeing Scale, the Pittsburgh Sleep Quality Index (PSQI) questionnaire, and the short form of the International Physical Activity Questionnaire. Results. Replies from older adults (aged &gt;55 years, n = 517), mainly from Europe (50.1%), Western-Asia (6.8%), America (30%), and North-Africa (9.3%) were analyzed. The COVID-19 lockdown led to significantly decreased mental wellbeing, sleep quality, and total physical activity energy expenditure levels (all p &lt; 0.001). Regression analysis showed that the change in total PSQI score and total physical activity energy expenditure (F-(2,F- 514) = 66.41 p &lt; 0.001) were significant predictors of the decrease in mental wellbeing from pre- to during lockdown (p &lt; 0.001, R-2: 0.20). Conclusion. COVID-19 lockdown deleteriously affected physical activity and sleep patterns. Furthermore, change in the total PSQI score and total physical activity energy expenditure were significant predictors for the decrease in mental wellbeing.</p
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