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In this study, we determined the refractive index of the air at different pressures and temperatures using a home-built Mach–Zehnder interferometer. The pressure and temperature were controlled using a home-built gas flow system and a temperature controller. A He–Ne laser operating at wavelengths of 632.8 nm was used to illuminate the Mach–Zehnder interferometer to obtain interference fringes. The changes in the number of fringes that crosses the field of view were exploited to calculate the variation in the refractive index with temperature and pressure. Some refractive index-dependent physical constants such as the thermo-optical constant (refractive index temperature coefficient dn/dT), dielectric constant, molar refractivity, and molecular polarizability were calculated for the air at different temperatures and pressure. In the pressure (66–80 cmHg) and temperature (303–338 K) range, the refractive index, dielectric constant, molar refractivity, and molecular polarizability of the air were found to vary between 1.000189 ± 0.000006–1.000281 ± 0.000007, 1.000379 ± 0.000010–1.000562 ± 0.000014, 4.03396 ± 0.13693–4.42908 ± 0.10860 cm3/mol, and 2.01 ± 0.07 × 10–29–2.21 ± 0.05 × 10–29m3, respectively.

The recently emerged SARS-CoV-2 caused a global pandemic since the last two years. The urgent need to control the spread of the virus and rapid application of the suitable health measures raised the importance of available, rapid, and accurate diagnostic approaches. The purpose of this study is to describe a rapid in-house optimized ELISA based on the expression of the receptor binding domain (RBD) of the SARS-CoV-2 spike protein in a prokaryotic system. We show the expression of the 30 kDa recombinant SARS-CoV-2 RBD-6×His in four different E. colistrains (at 28∘C using 0.25mM IPTG) including the expression strain E. coliBL21 (DE3) Rosetta Gami. SARS-CoV-2 rRBD-6×His protein was purified, refolded, and used as an antigen coat to assess antibody response in human sera against SARS-CoV-2 infection. The assessment was carried out using a total of 155 human sero-positive and negative SARS-CoV-2 antibodies. The ELISA showed 69.5% sensitivity, 88% specificity, 78.5% agreement, a positive predictive value (PPV) of 92.3%, and a negative predictive value of 56.5%. Moreover, the optical density (OD) values of positive samples significantly correlated with the commercial kit titers. Specific human antibodies against SARS-CoV-2 spike protein were detected by rapid in-house ELISA in sera of human COVID-19-infected patients. The availability of this in-house ELISA protocol would be valuable for various diagnostic and epidemiological applications, particularly in developing countries. Future studies are planned for the use of the generated SARS-CoV-2 rRBD-6×His protein in vaccine development and other diagnostic applications.

The performance of a membrane aerated biofilm reactor (MABR) treating raw municipal wastewater primary effluent was optimized. The MABR performance was challenged by the gradual increase of the organics and ammonia surface loading rates with hydraulic retention times (HRT) of 10.7, 6.24, 4.0, 2.0 and 3.0 h. With organics and ammonia surface loading rates of 20 g total chemical oxygen demand m−2d−1and 3.32  gNH4+-N m−2d−1, respectively, the reactor achieved simultaneous organics, nitrogen and total nitrogen reductions of 98, 96 and 67%, respectively. Microbial analysis indicated the coexistence of nitrite oxidizing bacteria, ammonia oxidizing bacteria, aerobic denitrifying bacteria and other bacteria within the MABR biofilm, correlating to simultaneous nitrification, denitrification and organics within the reactor. Acceptable effluent water quality was obtained when the MABR was operated at an HRT as low as 3 h.

Periodontal diseases are worldwide chronic inflammatory conditions that are associated with heavy production of reactive oxygen species followed by damage of the tooth-supporting tissues. Although the mechanical approach of scaling and root planing (SRP) for removing of plaque is considered as the key element for controlling periodontitis, the anatomical complexity of the teeth hinders accessibility to deeper points. The aim of this study was to design a micellar nanocarrier of coenzyme Q10 (Q10) to support the management of moderate periodontitis. Q10was formulated in nanomicelles (NMQ10) and evaluated regarding encapsulation efficiency, loading efficiency, percent yield, hydrodynamic size (Dh), polydispersity index (PDI), and zeta potential (ζpotential). NMQ10was incorporated to in situ gelling systems and the in vitro release of Q10was studied. A clinical study including evaluation of periodontal parameters and biochemical assay of total antioxidant capacity (T-AOC) and lipid peroxide was achieved. Results revealed that Q10was efficiently entrapped in spherical-shaped stable NMQ10with Dh, PDI, and ζpotential of 154.0 nm, 0.108, and − 31.67 mV, respectively. The clinical study revealed that SRP only exhibited improvement of the periodontal parameters. Also, assay of T-AOC and lipid peroxide revealed that their values diminished by 21.5 and 23.8%, respectively. On the other hand, SRP combined with local application of NMQ10resulted in a significant management of the periodontal parameters, and likewise, the assayed biomarkers proved enhanced antioxidant activity over SRP alone. In conclusion, NMQ10can be suggested as a promising nanosystem as an approach to support the management of chronic periodontitis. Such results could be used to conduct larger clinical studies.

Objective:Alzheimer's disease (AD), a neurodegenerative disorder, involves brain insulin signaling cascades and insulin resistance (IR). Because of limited treatment options, new treatment strategies are mandatory. Green coffee bean extract (GCBE) was reported to attenuate IR and improve brain energy metabolism. We aimed to investigate the possible use of GCBE as a prophylactic strategy to delay the onset of AD or combined with pioglitazone (PIO) as a strategy to retard the progression of AD.Methods:Rats received 10% fructose in drinking water for 18 weeks to induce AD. GCBE-prophylactic group received GCBE for 22 weeks started 4 weeks prior to fructose administration. The PIO group treated with PIO for 6 weeks started on week 12 of fructose administration. The GCBE+PIO group received GCBE for 22 weeks started 4 weeks prior to fructose administration and treated with PIO for the last 6 weeks of fructose administration.Results:Pretreatment with GCBE, either alone or combined with PIO, alleviated IR-induced AD changes. GCBE improved cognition, decreased serine phosphorylation of insulin receptor substrate, increased phosphoinositol-3 kinase (PI3K) activity and protein kinase B (Akt) gene expression, decreased glycogen synthase kinase-3β (GS3Kβ) gene expression and Tau hyperphosphorylation.Discussion:GCBE exerted neuroprotective effects against IR-induced AD mediated by alleviating IR and modulating brain insulin signaling cascade.

The mouse model of transverse aortic constriction (TAC) has been widely used as a cardiac stress in the investigation of the molecular mechanisms of cardiac hypertrophy. Recently, the International Knockout Mouse Consortium has selected the C57BL/6NTac (BL/6N) mouse strain to generate null alleles for all mouse genes; however, a range of genetic and cardiac phenotypic differences have been reported between this substrain and the commonly used C57BL/6J (BL/6J) substrain. It has been reported by Garcia-Menendez and colleagues that 12-week C57BL/6NTac mice are susceptible to heart failure but little is known about the cardiac remodeling in this substrain as cardiac function progresses from compensation to decompensation.

New strategies are needed to develop new drugs to treat emerging infectious diseases and microbial resistance. A new effective strategy is to design drugs combined with metal nanoparticles to overcome infections of multidrug-resistant microbes. In this study, we investigated the anti-microbial and anticancer properties of three differently shaped silver nanoparticles (S1-S3) against a wide range of microorganisms as well as two types of carcinoma cells. The three forms of silver nanoparticles (Ag-NPs) were investigated against Coxsackievirus B3 and 5 fungal strains (Aspergillus fumigatus, Candida albicans, Geotricum candidum, Aspergillus niger, Trichophyton mentagrophytes) while for antibacterial and anticancer evaluation, S2 was used. Our results demonstrated that all forms had antiviral activities against virus replication with TI ranging from 0.4 to 30 and reduction in virus titers ranged from 0 to 4 log10TCID50. On the other hand, only Ag-NPs S2 exhibited antifungal activities, mostly against Trichophyton mentagrophytes.Also, Ag-NP S2 showed antibacterial effects against some gram-negative bacteria (Escherichia coli, Acinetobacter baumannii, Klebsiella pneumonia, Salmonella typhi, and Enterobacter cloacae) and some positive bacteria (Bacillus subtilis, Staphylococcus aureus, Streptococcus mutans). Furthermore, Ag-NPs displayed a significant cytotoxic potential in cancerous Hep-G2 and A549 cell lines. The results obtained demonstrate that Ag-NPs can be utilized as strong antimicrobial and anticancer agents.

The provisional side-branch intervention strategy remains the gold standard approach for repair of coronary bifurcation lesions. We performed this study to evaluate the clinical and functional outcomes of using the instantaneous wave-free ratio (iFR) for physiological assessment in provisional side-branch repair of bifurcation lesions.

Legionella pneumophilahas recently been described as a major cause of water-related outbreaks in developed countries. In drinking water distribution and premise plumbing systems, L. pneumophilagrow within free-living amoeba hosts in biofilm. Exposure to Legionella-containing water aerosols generated during common water usages and in built environments is responsible for causing legionellosis in humans. Here we report that the amoeba, Willaertia magnaphagocytizes L. pneumophilain drinking water, supports intracellular growth, and releases L. pneumophilawithin vesicles of variable sizes before the trophozoites are completely lyzed to freely release the Legionellacells in the water environment. The vesicles produced in water at temperatures 22–40 °C varied in number, and ranged from 3 to 20 µm in diameter, mostly falling into the respirable size. The respirable-size vesicles that have a diameter of 3 to 10 µm may contain a maximum of 23–873 L.pneumophilacells, respectively, which could serve as a single human dose to initiate Legionellainfection according to the current human dose–response information. This study suggested that current culture-based standard monitoring of drinking water for L.pneumophilawould underestimate the true human health risk not only due to the inability of resolving viable but non-culturable bacterial cells but also due to underestimating the health impact of vesicle-bound Legionellacells. Thus, the regulatory guidelines for monitoring and controlling L.pneumophilashould include amoebae in the surveillance of drinking water and introduce evidence-based strategies to control amoebae as an indirect and effective way of controlling legionellosis.

PURPOSE:To evaluate the clinical results of epitheliumoff corneal cross-linking (CXL) during a 7-year follow-up.METHODS:This retrospective, non-randomized, single-center interventional study enrolled 34 consecutive eyes of 24 patients with progressive keratoconus undergoing CXL surgery with epithelium removal. Visual, refractive, corneal topographic, pachymetric, and anterior segment changes were evaluated at 1, 3, and 7 years after surgery.RESULTS:Significant reduction of refraction was observed at 1 year postoperatively (Significant reduction of refraction was observed at 1 year postoperatively (P≤ .006), with an additional significant reduction between the 1- and 3-year postoperative visits (P≤ .002) and no significant changes afterward (P≥ .156). Regarding corrected distance visual acuity (CDVA), a significant improvement was detected at 1 year after surgery (P< .001), with an additional improvement between 1 and 3 years postoperatively (P= .001), and no significant changes at the end of the follow-up (P= .518). Significant corneal flattening was observed at 1, 3, and 7 years after surgery (P≤ .041). Likewise, a significant central thinning was observed at 1 year postoperatively (P< .001), with no significant changes afterward (P≥ .112). Anterior maximum elevation only changed significantly between 1 and 3 years after surgery (P= .002), whereas the posterior maximum elevation changed significantly at all time points of the follow-up (P≤ .034). No significant changes with surgery in anterior segment volume (P≥ .377) and anterior chamber depth (P≥ .142) were detected.CONCLUSIONS:The effect of epithelium-off CXL in progressive keratoconus is maintained 7 years after surgery. Long-term corneal changes after this procedure may be influenced by an age-related corneal stiffening process.[[J Refract Surg.2018;34(3):181–186.]

PURPOSE:To compare the clinical outcomes of small incision lenticule extraction (SMILE) and wavefront-guided LASIK (WFG LASIK) in eyes with low and moderate myopia.METHODS:This was a prospective, comparative study enrolling 110 eyes with low and moderate myopia (spherical equivalent ≤ 6.00 diopters [D]). Two groups were differentiated according to the surgical technique used: the WFG LASIK group included 51 eyes (51 patients) undergoing WFG LASIK using the STAR S4IR excimer laser and the iDesign aberrometer (Abbott Medical Optics, Abbott Park, IL) and the SMILE group included 59 eyes (59 patients) undergoing SMILE with the VisuMax platform (Carl Zeiss Meditec, Jena, Germany). Visual, refractive, aberrometric, and contrast sensitivity outcomes were evaluated during a 6-month follow-up.RESULTS:Mean efficacy index was 0.92 ± 0.11 and 1.12 ± 0.17 in the SMILE and WFG LASIK groups, respectively (Mean efficacy index was 0.92 ± 0.11 and 1.12 ± 0.17 in the SMILE and WFG LASIK groups, respectively (P< .001). Postoperative spherical equivalent was within ±0.50 D in 81.54% and 98% of eyes in the SMILE and WFG LASIK groups (P< .001), and postoperative cylinder was 0.50 or below in 84.7% and 100% of eyes, respectively (P= .038). Mean safety index was 0.98 ± 0.08 and 1.20 ± 0.14 in the SMILE and WFG LASIK groups (P< .001), with losses of lines of corrected distance visual acuity in 6.8% and 0.0% of eyes, respectively. Higher increase in higher order (P< .001) and coma (P< .001) root mean square and higher decrease in contrast sensitivity for 6, 12, and 18 cycles/degree (P≤ .001) were observed after SMILE.CONCLUSIONS:SMILE and WFG LASIK are efficacious and safe procedures for the correction of low and moderate myopia, but WFG LASIK allows a more predictable outcome and better aberrometric control. SMILE and WFG LASIK are efficacious and safe procedures for the correction of low and moderate myopia, but WFG LASIK allows a more predictable outcome and better aberrometric control. [[J Refract Surg.2017;33(5):298–304.]

PURPOSE:To evaluate in a pilot study the visual, refractive, corneal topographic, and aberrometric changes after wavefront-guided LASIK or photorefractive keratectomy (PRK) using a high-resolution aberrometer to calculate the treatment for aberrated eyes.METHODS:Twenty aberrated eyes of 18 patients undergoing wavefront-guided LASIK or PRK using the VISX STARS4IR excimer laser and the iDesign aberrometer (Abbott Medical Optics, Inc., Santa Ana, CA) were enrolled in this prospective study. Three groups were differentiated: keratoconus post-CXL group including 11 keratoconic eyes (10 patients), post-LASIK group including 5 eyes (5 patients) with previous decentered LASIK treatments, and post-RK group including 4 eyes (3 patients) with previous radial keratotomy. Visual, refractive, contrast sensitivity, corneal topographic, and ocular aberrometric changes were evaluated during a 6-month follow-up.RESULTS:An improvement in uncorrected (UDVA) and corrected visual acuity (CDVA) associated with a reduction in the spherical equivalent was observed in the three groups, but was only statistically significant in the keratoconus post-CXL and post-LASIK groups (An improvement in uncorrected (UDVA) and corrected visual acuity (CDVA) associated with a reduction in the spherical equivalent was observed in the three groups, but was only statistically significant in the keratoconus post-CXL and post-LASIK groups (P≤ .04). All eyes gained one or more lines of CDVA after surgery. Improvements in contrast sensitivity were observed in the three groups, but they were only statistically significant in the keratoconus post-CXL and post-LASIK groups (P≤ .04). Regarding aberrations, a reduction was observed in trefoil aberrations in the keratoconus post-CXL group (P= .05) and significant reductions in higher-order and primary coma aberrations in the post-LASIK group (P= .04).CONCLUSIONS:Wavefront-guided laser enhancements using the evaluated platform seem to be safe and effective to restore the visual function in aberrated eyes.[[J Refract Surg.2015;31(6):411–418.]

PURPOSE:To compare the refractive and visual outcomes of variable spot scanning ablation versus the wavefront-optimized ablation for myopia and myopic astigmatism.METHODS:Fifty patients with myopia who underwent LASIK (100 eyes) were divided into two equal groups. Myopic correction performed using the variable spot scanning (VSS) ablation with the VISX STAR S4/IR platform (Abbott Medical Optics, Inc., Santa Ana, CA) (VSS group) and wavefront-optimized (WFO) ablation profile with the WaveLight Allegretto Wave Eye-Q platform (Alcon Laboratories, Inc., Fort Worth, TX) (WFO group). Manifest refraction, uncorrected distance visual acuity, and corrected distance visual acuity were obtained preoperatively and 1 day and 1 and 3 months postoperatively. Wavefront measurement and contrast sensitivity testing were done preoperatively and 3 months postoperatively.RESULTS:Postoperative mean refractive spherical equivalent was −0.14 ± 0.2 diopters for the VSS group and −0.15 ± 0.28 diopters for the WFO group. Forty-eight eyes of the VSS group and 47 eyes of the WFO group were within ±0.5 diopters. Postoperative mean corrected distance visual acuity was 1.05 ± 0.13 for the VSS group and 1.06 ± 0.12 for the WFO group. The postoperative uncorrected distance visual acuity was 1.01 ± 0.16 for the VSS group and 1.01 ± 0.11 for the WFO group. The safety index was 1.12 for the VSS group and 1.06 for the WFO group, whereas the efficacy index was 1.07 for the VSS group and 1.01 for the WFO group. The mean induced positive spherical aberration was 0.041 ± 0.046 Postoperative mean refractive spherical equivalent was −0.14 ± 0.2 diopters for the VSS group and −0.15 ± 0.28 diopters for the WFO group. Forty-eight eyes of the VSS group and 47 eyes of the WFO group were within ±0.5 diopters. Postoperative mean corrected distance visual acuity was 1.05 ± 0.13 for the VSS group and 1.06 ± 0.12 for the WFO group. The postoperative uncorrected distance visual acuity was 1.01 ± 0.16 for the VSS group and 1.01 ± 0.11 for the WFO group. The safety index was 1.12 for the VSS group and 1.06 for the WFO group, whereas the efficacy index was 1.07 for the VSS group and 1.01 for the WFO group. The mean induced positive spherical aberration was 0.041 ± 0.046 µm for the VSS group and 0.195 ± 0.171 µm for the WFO group (P< .001). Mesopic contrast sensitivity testing showed no statistically significant differences between groups at all tested spatial frequencies.CONCLUSIONS:Both VSS and WFO treatments showed similar refractive and visual outcomes. Both induced significant positive spherical aberration, significantly more with WFO.[[J Refract Surg. 2015;31(1):22–28.]

PURPOSE:To evaluate the 4-year visual, refractive, and contrast sensitivity outcomes of wavefront-guided LASIK for the correction of low to moderate myopia using the VISX CustomVue technology (Abbott Medical Optics, Inc., Santa Ana, CA).METHODS:This was a prospective study including 255 consecutive eyes of 145 patients (age range: 19 to 55 years) with low to moderate myopia (mean spherical equivalent: −3.36 ± 1.71 diopters [D]) undergoing laser refractive surgery. Wavefront-guided LASIK was performed in all eyes using the VISX STAR S4 IR excimer laser platform and the CustomVue procedure for the ablation profile design. Visual, refractive, and contrast sensitivity changes were evaluated during a 4-year follow-up period.RESULTS:Postoperative logMAR uncorrected distance visual acuity was 0.1 or better (20/25 Snellen) in 98.0% and 100% of eyes at 1 and 4 years, respectively. At 4 years postoperatively, mean spherical equivalent was reduced significantly to a mean value of −0.22 ± 0.28 D (Postoperative logMAR uncorrected distance visual acuity was 0.1 or better (20/25 Snellen) in 98.0% and 100% of eyes at 1 and 4 years, respectively. At 4 years postoperatively, mean spherical equivalent was reduced significantly to a mean value of −0.22 ± 0.28 D (P< .01), with 97.3% of eyes with a spherical equivalent within ±0.50 D. The astigmatic power vector component J0of manifest refraction was also reduced significantly (P< .01). Postoperative logMAR corrected distance visual acuity was 0.0 or better (20/20 Snellen) in 96.1% and 98.8% of eyes at 1 and 4 years, respectively. Improvement in contrast sensitivity was observed in some spatial frequencies between 1 and 4 years postoperatively. No significant correlations were found between 4-year contrast sensitivity and corrected distance visual acuity (0.024 ⩽ r⩽ −0.120, P⩾ .06).CONCLUSION:Wavefront-guided LASIK using the VISX CustomVue technology provides an effective and predictable correction of low to moderate myopia in the long term, preserving the patient’s visual acuity and quality.[[J Refract Surg.2013;29(12):816–822.]

In corneal refractive surgery, postoperative ectasia risk assessment routinely includes pachymetric analysis at the apex and thinnest point. We examined whether these data differ worldwide and constructed preliminary country-specific normative thresholds.

Alzheimer’s disease (AD) is a progressive disease that attacks the brain’s neurons and causes problems in memory, thinking, and reasoning skills. Personalized Medicine (PM) needs a better and more accurate understanding of the relationship between human genetic data and complex diseases like AD. The goal of PM is to tailor the treatment of a case person to his individual properties. PM requires the prediction of a person’s disease from genetic data, and its success depends on the accurate detection of genetic biomarkers. Single Nucleotide polymorphisms (SNPs) are considered the most prevalent type of variation in the human genome. Epistasis has a biological relevance to complex diseases and has an important impact on PM. Detection of the most significant epistasis interactions associated with complex diseases is a big challenge. This paper reviews several machine learning techniques and algorithms to detect the most significant epistasis interactions in Alzheimer’s disease. We discuss many machine learning techniques that can be used for detecting SNPs’ combinations like Random Forests, Support Vector Machines, Multifactor Dimensionality Reduction, Neural Network, and Deep Learning. This review paper highlights the pros and cons of these techniques and explains how they can be applied in an efficient framework to apply knowledge discovery and data mining in AD disease.

In the present study the chemopreventive activities of DFMO, the irreversible inhibitor of ornithine decarboxylase, and finasteride, the inhibitor of prostatic 5a-reductase, against the development of chemically induced prostate adenocarcinoma by methylnitrosourea/testosterone propionate in male Wistar rats were investigated. According to histological examination, oral administration of DFMO and finasteride, either alone or combined, for two months to MNU/TP-inoculated rats reduced the tumor incidence to 11.11%, 10% and 10%, respectively, compared to tumored controls (64.3%). DFMO and/or finasteride treatment resulted in significant reductions in the wet weight of the prostate gland and seminal vesicles and its ratio relative to the total body weight, as well as the levels of prostate total protein, DNA, RNA and DNA/RNA ratio, compared to tumored controls. However, the effect of the combined treatment was of no statistical significance compared to single DFMO or finasteride treatment, as demonstrated by the non-significant differences between the mean values of most of the studied parameters. The tumor chemopreventive activity and the prostate growth inhibitory effect of DFMO and finasteride were due to suppression of prostate polyamine synthesis. ANOVA test revealed that the relative weight of the prostate as well as blood and tissue polyamine levels could be used as significant endpoint biomarkers for DFMO and finasteride as cancer chemopreventive agents.