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Although the causes of depression include a wide range of conditions, from neurodegenerative to thyroid, they all have one common denominator, changes in the brain. Depression can be located in multiple brain regions simultaneously, which may be derived from a common molecular abnormality found in neurons in many brain regions. Abnormalities of receptors or impulse transmission could be the answer. In this work, a simple and accurate spectrophotometric method was developed for the analysis of escitalopram oxalate in various pharmaceutical formulations. In this method, absorbance was measured at 238 nm for escitalopram oxalate. Method validation parameters were studied. The method can be used for quality control of pharmaceutical forms containing escitalopram. Also, by the same method, the actual active substance concentrations compared to those listed on the package, the standard deviations and the relative standard deviations.

Human health decline is most commonly manifested by pain and sometimes fever in the initial phase of the disease. Analgesics, antipyretics and anti-inflammatories serve as drugs with various chemical structures which showcase in different proportions their main actions. They represent medicines that suppress pain and fight fever. The aim of the paper is studying the usual types of therapeutic indications using modern spectral analysis, based on the analgesic, antipyretic and anti-inflammatory actions. The following spectral analysis methods are used to control the chemical compositions of the studied drugs: UV-VIS analyses and IR analyses.

In rheumatoid arthritis the extra-articular manifestations present a marker of disease severity and are accompanied by increased morbidity and mortality The aim of this paper is to study the relationship between extra-articular manifestations and osteoporosis in patients with rheumatoid arthritis. The study included 130 menopausal women diagnosed with rheumatoid arthritis. Bone mineral density was measured at lumbar spine and femoral by means of dual X-ray osteodensitometry. The obtained variables were analysed by bivariate analysis and logistic regression. The mean age was 62.77±7.51 years old. The medium duration of rheumatoid arthritis was 7.91±7.85 years, the frequency of extra-articular manifestations was 25.38%. The frequency of osteoporosis was 44.62%. The frequency of osteoporosis is statistically significantly higher in patients with rheumatoid arthritis who have extra-articular manifestations. The presence of extra-articular manifestations in patients with rheumatoid arthritis should draw attention to the need to determine bone mineral density.

Introduction. Pregnancy is a well-known risk factor for asymptomatic hemangiomas discovered incidentally, becoming aggressive or symptomatic, most often in the third trimester of pregnancy, related to hemodynamic and endocrine changes that occur during pregnancy. Many patients experience incomplete spontaneous remission after birth. Material and method. We report the case of a 24-year-old woman, who presented for incomplete paraplegia, pain in the spine, instability of walking of the left lower limb, bilateral plantar paresthesia, possible walking with metal support. Results and discussions. The MRI performed identifies T9 vertebral fracture-compression on pathological bone, T10-T12 vertebral hemangiomas. Conclusions. In order to obtain favorable results, the patient benefited from the support and treatment of a multidisciplinary team: neurosurgeons, imagers, physical and rehabilitation medicine doctors and physiotherapists, and represented a real challenge regarding the complexity of the factors involved. Keywords: hemangioma, rehabilitation, multidisciplinary team

Objective To evaluate color, lightness, chroma, hue, and translucency adjustment potential of resin composites using CIEDE2000 color difference formula. Methods Three resin composites (Filtek Universal, Harmonize, and Omnichroma) were tested. Two types of specimens were prepared: an outer base shade with an inner hole filled with test shades and single-composite specimens of all shades. Spectrorradiometric reflectances measurements and subsequent CIELAB color coordinates and translucency parameter (TP) were performed. Color (CAP00 ), lightness, chroma, hue, and translucency (TAP00 ) adjustment potential using CIEDE2000 color difference were computed. Color and transparency differences among composite materials and shades were statistically tested (P Results Positive CAP00 and TAP00 values were found for majority of tested materials. CAP00 values ranged from -0.14 to 0.89, with the highest values found for Omnichroma (>0.75 in all cases). TAP00 values ranged from -0.06 to 0.86 with significant translucency differences among dual and single specimens. Omnichroma exhibited the highest adjustment potential for all color dimensions studied. Conclusions Lightness, hue, chroma, and translucency adjustment potential have been introduced using CIEDE2000 color difference formula, and have shown their usefulness to evaluate blending effect in dentistry. Color coordinates and translucency adjustment potential were dependent on dental material. Omnichroma exhibited the most pronounced blending effect. Clinical significance Resin composites with increased color and translucency adjustment may simplify shade selection, making this process easier and less time consuming. Furthermore, these materials might facilitate challenging and complex color matching situations.

The present article starts from the already well-known relationship between translation studies and pragmatics and aims to offer an analysis of the way in which several instances of irony in John Galsworthy’s novels are translated into Romanian. The paper approaches the phenomenon of irony comprising pragmatic theories such as: irony as substitute of literal meaning, as echoic mention, as pretence or simulation of illocutionary force of speech acts.

The deleterious effects of the coronavirus disease 2019 (COVID-19) pandemic urged the development of diagnostic tools to manage the spread of disease. Currently, the “gold standard” involves the use of quantitative real-time polymerase chain reaction (qRT-PCR) for SARS-CoV-2 detection. Even though it is sensitive, specific and applicable for large batches of samples, qRT-PCR is labour-intensive, time-consuming, requires trained personnel and is not available in remote settings. This review summarizes and compares the available strategies for COVID-19: serological testing, Point-of-Care Testing, nanotechnology-based approaches and biosensors. Last but not least, we address the advantages and limitations of these methods as well as perspectives in COVID-19 diagnostics. The effort is constantly focused on understanding the quickly changing landscape of available diagnostic testing of COVID-19 at the clinical levels and introducing reliable and rapid screening point of care testing. The last approach is key to aid the clinical decision-making process for infection control, enhancing an appropriate treatment strategy and prompt isolation of asymptomatic/mild cases. As a viable alternative, Point-of-Care Testing (POCT) is typically low-cost and user-friendly, hence harbouring tremendous potential for rapid COVID-19 diagnosis.

In infectious diseases, viral hepatitis has an increased incidence, being an important cause of morbidity and mortality, being a "sentinel" indicator of the socio-economic and hygienic-cultural standard of a geographical area. The World Health Organization (WHO) admits the following types of hepatitis viruses: A, B, B + D, C, E, F and G. Among the viral entities recognized by the WHO, a special importance in terms of incidence, evolution over time with the risk of chronicity and the therapeutic options are presented by hepatitis B and C. There is currently an effective vaccine as well as treatment for hepatitis B. There is no vaccine for hepatitis C, but in recent years considerable progress has been made in treating this disease. Also, the introduction of drugs known as direct-acting antivirals makes it possible to cure over 90% of patients within 2-3 months. But in many countries, current drug policies, regulations and prices keep treatment out of the reach of most people with hepatitis. Eradication of viral hepatitis is possible if greater emphasis is placed on prevention, diagnosis and treatment. Vaccination is very important, as it is possible for types A and B of hepatitis. Early diagnosis is also extremely important, given that there are currently very effective drugs that can prevent the development of liver cancer. The WHO also noted that about two million people worldwide become ill each year due to the reuse of syringes and stressed the importance of checking blood donors to see if they are not carriers of hepatitis B or C viruses. Therefore, the purpose of this article is to highlight the pharmacological treatment and the main therapeutic and prevention schemes currently used for patients with these liver diseases. The paper was based on the most popular methods of identification of the latest international information about the treatment of hepatitis (by electronic search using Pubmed, SciFinder, Scirus, GoogleScholar and Web of Science). We also consulted the global literature cited in the hepatitis database of the World Health Organization (WHO) updated frequent from the current literature on this topic.

Seaweeds are widely used in the life science as source of compounds with diverse structural forms and biological activities, therefore, potential source of new antioxidant activity. The algae of the Black Sea have not been adequately explored for their potential as a source of bioactive substances. In this context, Brown algae Cystoseira barbata isolated from Black Sea coastal waters of Romania, were evaluated for their bioactivity potential. The results from Cystoseira barbata were obtained: for total phenolic content obtained in ethanolic extracts (TPC): 385.6 � 1.85 mg GAE/100 g f.w. Phenolic Acids quantified by HPLC-DAD from hydroethanolic extract of Cystoseira barbata from Black Sea was 80.14% from total phenolic content identified. We showed that Cystoseira barbata from the Romanian shore of the Black Sea contains vanillic acid in highest quantity (99.5�0.08 mg/100 g f.w.), followed by benzoic acid (65.7�0.06 mg/100 g f.w.) and feluric acid (54.5�0.01 mg/100 g f.w.). The smallest quantities were for gallic acid (3.5�0.03 mg/100 g f.w.), pyrogallol acid (4.2�0.05 mg/100 g f.w.) and 4-amino-benzoic acid (5.2�0.09 mg/100 g f.w.). Cystoseira barbata has a total content of large phenols and also has strong antioxidant and antimicrobial activity. Antioxidant activity (ACL) was studied using DPPH radical scavenging activity and reducing power. The extracts containing high levels of total phenolic content were also potent DPPH radical scavengers. The IC50 (�g/mL) for Cystoseira barbata in methanolic extract was 942.92� 2.56 �g/mL. High absorbance obtained from reducing power assay indicates high reducing power, measured values of absorbance varied from 0.0901 at 0.9223.

Worldwide, marine algae are known to produce a wide variety of bioactive secondary metabolites and several compounds have been derived from them for the prospective development of novel drugs by the pharmaceutical industry. In this context, Ulva lactuca, Enteromorpha intestinales, and Cladophora vagabunda, isolated from Black Sea coastal waters of Romania, were evaluated for their potential for bioactivity. Extracts of the algae selected for the study were prepared using ethanol. The study presents original results concerning the total phenolic content (TPC), determined by the spectrometric method (Folin-Ciocalteu method) and the individual phenols from each species of seaweed studied were identified by HPLC-DAD techniques. Total antioxidant activity (ACL) was studied by photochemiluminescence method, and antibacterial activity was studied on two strains of bacteria, Escherichia coli ATCC 10536 - gram-negative and Staphylococcus aureus ATCC 6538P - gram-positive. Results indicated that the highest total phenolic content was obtained for Cladophora vagabunda (325.8 mg/100 g f.w.), followed by Ulva lactuca (285.5 mg/100 g f.w.) and the lowest rate was registered by Enteromorpha intestinalis (268.8 mg/100 g f.w.). Through HPLC-DAD techniques, 6 individual phenolic compounds were identified in all analyzed seaweeds. In addition, two other phenolic compounds were identified in lower concentrations in Ulva lactuca, but only one phenolic compound in Enteromorpha intestinalis. The results of this study show that there is a strong correlation between antioxidant activity (ACL), antibacterial activity and total phenolic content (TPC). Antioxidant activity shows the same order as total phenolic content (TPC): Cladophora vagabunda (64.15 nmol/g sample) followed by Ulva lactuca (22.8 nmol/g sample) and Enteromorpha intestinalis (10.4 nmol/g sample). The antibacterial activity recorded in all green seaweeds shows that the inhibition sites are higher on Escherichia coli compared to Staphylococcus aureus.

This first chapter presents the basic principles of color science and their application to dentistry. It includes color coordinates, color differences, whiteness indexes, and the most relevant optical properties such as transmittance, absorption, scattering, fluorescence, translucency, and opacity. Measuring and evaluating methods are described and relevant literature and standards are reported. Therefore, this chapter is essential to understand color science and optical properties, assisting any dental professional in performing and interpreting color science studies, improving the practice of esthetic dentistry by applying such knowledge to design and manufacture restorative material systems and, finally, to restore the missing dental structures.

Significance: Recent generation of bioengineered human skin allowed the efficient treatment of patients with severe skin defects. However, the optical and biomechanical properties of these models are not known. Aim: Three models of bioengineered human skin based on fibrin-agarose biomaterials (acellular, dermal skin substitutes, and complete dermoepidermal skin substitutes) were generated and analyzed. Approach: Optical and biomechanical properties of these artificial human skin substitutes were investigated using the inverse adding-doubling method and tensile tests, respectively. Results: The analysis of the optical properties revealed that the model that most resembled the optical behavior of the native human skin in terms of absorption and scattering properties was the dermoepidermal human skin substitutes after 7 to 14 days in culture. The time-course evaluation of the biomechanical parameters showed that the dermoepidermal substitutes displayed significant higher values than acellular and dermal skin substitutes for all parameters analyzed and did not differ from the control skin for traction deformation, stress, and strain at fracture break. Conclusions: We demonstrate the crucial role of the cells from a physical point of view, confirming that a bioengineered dermoepidermal human skin substitute based on fibrin-agarose biomaterials is able to fulfill the minimal requirements for skin transplants for future clinical use at early stages of in vitro development., Ministry of Science, Innovation and Universities of Spain PGC2018-101904-A-I0, Instituto de Salud Carlos III (ISCIII), Ministry of Science, Innovation and Universities, through AES 2017 AC17/00013, Instituto de Salud Carlos III (ISCIII), Ministry of Science, Innovation and Universities within EuroNanoMed framework, EU AC17/00013, University of Granada A.TEP.280.UGR18, Junta de Andalucía PE-0395-2019, Fundación Benéfica Anticancer San Francisco Javier y Santa Cándida, Granada, Spain, OTRI.35A-07

Drug-resistant tuberculosis (DR-TB) continues to be a major public health challenge with suboptimal treatment outcomes including well-documented treatment-related toxicities. We compared the cost-effectiveness of bedaquiline (BDQ) containing regimens with injectable containing regimens (short-course regimen [SCR] and long-course regiman [LCR]) in India, Russia, and South Africa.The analysis evaluated the direct costs of DR-TB treatment which included drugs, hospitalization, injectable-related adverse event costs, and other costs. Scenarios altered regimen costs, SCR/LCR ratio, and substitution rate between regimens (whether BDQ or injectable containing).BDQ containing regimens are more cost effective based on cost per treatment success compared with injectable containing regimens, reducing these in SCR by 18-20% and in LCR by 49-54%. Average cost effectiveness ratios (ACERs) of BDQ containing regimens are lower. The incremental cost effectiveness ratio (ICER) is negative. Exclusive use of BDQ containing regimens results in approximately 61,000 more patients treated successfully over 5 years.Across all countries, BDQ containing regimens are dominant compared to injectable containing regimens, entailing lower treatment costs to achieve better clinical outcomes. This analysis can provide insight and support to local and global decision-makers and public health organizations to allocate efficiently resources improving patient and public health outcomes.

The present article aims to offer a theoretical, yet partial, insight into the linguistic analysis of mentalities (the pragmatic and discursive approach), when the given corpus is the literary text and, even more, when we compare literary works of different authors from different cultures and/or ages.

Inflammation and oxidative stress play an important role in destabilizing artherosclerotic plaque in patients with acute coronary syndrome. In the present study we tried to establish the role of myeloperoxidase, an inflammatory marker secretory of activated neutrophils, in the diagnosis and prognosis of patients with acute chest pain presenting to the emergency department. In our study, MPO (myeloperoxidase) was determined at three different times: T1 – at the admission; T2 – at 48 hours from the admission; T3 – at discharge. MPO can be a diagnostic marker for patients with NSTEACS because it has significantly higher values compared to the control group, from the moment of their presentation in the emergency department (1.7364±0.8356 U/ml, pT

The optical properties of transparent conductive electrodes (TCEs) based on indium tin oxide (ITO) films deposited on polyethylene terephthalate (PET) substrates were evaluated in this work making use of the Inverse Adding-Doubling (IAD) iterative method. This technique allowed us to obtain the scattering and absorption coefficients explaining the optical behavior of the ITO-PET samples. The results pointed out that absorption is the most noticeable optical extinction process that occurs when light travels through this material.

Stroke is a common cause of adult disability and the third cause of death in Western European countries. Carotid disease is a well-known risk factor for ischemic stroke, and this relationship is established. However, only a minority of the population with atherosclerosis will have a stroke. The aim of these paper is to establish the relation between carotid atherosclerosis and first ischemic stroke. We performed an observational study, including 159 patients with carotid atherosclerosis. Our patients were examined with carotid ultrasound examination and cranio-cerebral computed tomography. We excluded patient with other cause of cerebral ischemia such atrial fibrillation, myocardial infarction, arterial dissection, vasculopathy, neoplasia. We also excluded any kind of transient cerebral ischemia, because of heterogeneity and poor medical documentation. Despite our efforts to treat this condition, carotid disease remains a powerful risk factor for ischemic stroke.

OBJECTIVE To determine 50:50% perceptibility threshold (PT) and 50:50% acceptability threshold (AT) for computer-simulated samples of human gingiva using CIEDE2000 and CIELAB color difference formulas. MATERIALS AND METHODS Each of the 60 pairs of simulated human gingiva was displayed on a calibrated monitor, together with three pairs of upper central incisors of different lightness. The color of gingiva left and right from the midline was compared. A total of 30 observers (15 dentists, 15 laypersons) participated in the study. CIEDE2000 and CIELAB formulas were used to calculate the thresholds and a Takagi-Sugeno-Kang Fuzzy Approximation model was used as fitting procedure. Paired t-test (α = 0.05) was used in evaluation of statistical significance of differences. RESULTS The PT and AT for CIEDE2000 and 95% confidence intervals were 1.1 [0.4, 1.7] and 2.8 [1.8, 4.0], respectively. Corresponding CIELAB values were 1.7 [0.2, 2.6] and 3.7 [2.1, 5.7]. Significant differences (P

The optical properties of a tissue or a biomaterial can be described in terms of the absorption coefficient (μa), the scattering coefficient (μs), the scattering function p(θ,ψ) and the real refractive index of the biomaterial. The Inverse Adding-Doubling, IAD, Method and relationship between the Kubelka- Munk parameters and the transport coefficients are used to describe optical properties at different wavelengths for a large variety of tissues and tissue like biomaterials, such as native cornea, tissue engineered cornea, tissue engineered oral mucosa, natural dentin and dental resin nanocomposites, among others

Ganglioneuromas are rare tumors, known as neuroblastic or neurogenic tumors, which most often start in autonomic nerve cells, which may be found in any part of the body. We present a case of 53 years old, woman, with mild arterial hypertension, who has right sided hemiparesis, more on the leg, with gradual onset. Cerebral MRI was normal. After a few months, she developed motor deficit on the opposite leg, with the picture of triparesis and impairment of walking. MRI of the cervical spine was showing an extra medullary intradural mass C5-C6-C7 and she finally underwent extended cervical laminectomy from C-5 to C-7 level, and total ablation of the tumor. Despite the first supposition of a neurinoma, histopathology examination confirmed a case of ganglioneuroma tumor. In a few weeks, she became confused and with impairment of gait. An obstructive hydrocephalus was confirmed on CT scan. The ventriculo-peritoneal shunt was performed and the recovery was complete.

Ideally, biomaterials designed to play specific physical and physiological roles in vivo should comprise components and microarchitectures analogous to those of the native tissues they intend to replace. For that, implantable biomaterials need to be carefully designed to have the correct structural and compositional properties, which consequently impart their bio-function. In this study, we showed that the control of such properties can be defined from the bottom-up, using smart surface templates to modulate the structure, composition, and bio-mechanics of human transplantable tissues. Using multi-functional peptide amphiphile-coated surfaces with different anisotropies, we were able to control the phenotype of corneal stromal cells and instruct them to fabricate self-lifting tissues that closely emulated the native stromal lamellae of the human cornea. The type and arrangement of the extracellular matrix comprising these corneal stromal Self-Lifting Analogous Tissue Equivalents (SLATEs) were then evaluated in detail, and was shown to correlate with tissue function. Specifically, SLATEs comprising aligned collagen fibrils were shown to be significantly thicker, denser, and more resistant to proteolytic degradation compared to SLATEs formed with randomly-oriented constituents. In addition, SLATEs were highly transparent while providing increased absorption to near-UV radiation. Importantly, corneal stromal SLATEs were capable of constituting tissues with a higher-order complexity, either by creating thicker tissues through stacking or by serving as substrate to support a fully-differentiated, stratified corneal epithelium. SLATEs were also deemed safe as implants in a rabbit corneal model, being capable of integrating with the surrounding host tissue without provoking inflammation, neo-vascularization, or any other signs of rejection after a 9-months follow-up. This work thus paves the way for the de novo bio-fabrication of easy-retrievable, scaffold-free human tissues with controlled structural, compositional, and functional properties to replace corneal, as well as other, tissues., Graphical abstract Image 1

Chitin and chitosan have become of great interest not only as underutilized resources, but also as new functional materials of high potential in various fields. The methods of isolating chitosan from different sources: shrimp (Panaeus monodon), crab (Scylla olivicea and Scylla serrata), locust (Schistocerca gregaria), honeybee (Apis mellifera), beelte (Calosoma rugosa) and fish (Labeo rohita) were compared. The same steps of demineralization and deproteinization were followed for the chemical extraction of chitin, but the concentration of reagents, the temperatures and reaction times were varied, which resulted in chitosans with different degrees of deacetylation.

The studied compounds are gels with meloxicam, piroxicam and tenoxicam in different solvents. The problem of solubilization of these compounds is generated by their poor solubility in hydrophilic media. Also, when applying local non-steroidal anti-inflammatory drugs (NSAIDs) in the form of ointments, the local concentration of the active substance is much higher than in the untreated tissue. The amount of NSAIDs required to produce a therapeutic effect by topical administration is much lower than in oral administration. Side effects may, however, occur as a local irritation from the time a topical formulation is applied. This paper presents the solubilization tests performed for pharmaceutical compounds of the NSAID class in different hydrophilic media. The test conclusions are useful because their solubility can be increased by using solvents (polar or non-polar) and surfactants. The conclusions of the solubility tests help in choosing solvents in the formulation and technologicalization of semi-solid preparations with topical application.

While tissue engineering is widely used to construct complex tridimensional biocompatible structures, researchers are now attempting to extend the technique into the fourth dimension. Such fourth dimension consists in the transformation of 3D materials over time, namely, by changing their shape, composition, and/or function when subjected to specific external stimuli. Herein, producing a 4D biomaterial with an internal mechanism of stimulus, using contractile cells as bio‐actuators to change tissue shape and structure, is explored. Specifically, producing cornea‐shaped, curved stromal tissue equivalents via the controlled, cell‐driven curving of collagen‐based hydrogels. This is achieved by modulating the activity of the bio‐actuators in delimited regions of the gels using a contraction‐inhibiting peptide amphiphile. The self‐curved constructs are then characterized in terms of cell and collagen fibril reorganization, gel stiffness, cell phenotype, and the ability to sustain the growth of a corneal epithelium in vitro. Overall, the results show that the structural and mechanical properties of self‐curved gels acquired through a 4D engineering method are more similar to those of the native tissue, and represent a significant improvement over planar 3D scaffolds. In this perspective, the study demonstrates the great potential of cell bio‐actuators for 4D tissue engineering applications.

The effect of Stevia extracts on in vitro Streptococcus mutans biofilm formation and in vivo plaque pH was evaluated in this paper. Three 10% solutions containing stevioside, rebaudioside A or sucrose were prepared. MTT assay was used to evaluate microbiological counts in vitro. Twenty volunteers rinsed for 1 min with each solutions, and plaque pH was measured at 7 time points after each rinse. Higher in vitro S. mutans biofilm formation was observed in sucrose solution (p < 0.01). After 5, 10, 15 and 30 min, the sucrose in vivo rinse produced a statistically significantly lower pH value compared to the Stevia extracts (F = 99.45, p < 0.01).Stevia extracts can be considered nonacidogenic.

In this work, the rheological properties of the biomaterial fibrin with different agarose concentrations, used for the generation of a bioengineered human corneal stroma by tissue engineering, before and after using a nanostructuring technique, were analyzed. The transparency of these artificial human stromas was also investigated. The temporal evaluation of the properties of these biomaterials is essential for the design of functional biological human corneal replacements. The nanostructuring technique used for the generation of nanostructured corneal constructs (NCCs) had a major influence on the rheological properties of the fibrin–agarose corneal equivalents. For an oscillatory shear stress of 1 Hz, well in the order of the natural oscillations of the human cornea, the NCCs had viscoelasticity values higher than those of non-nanostructured corneal constructs (N-NCCs), but similar to those of an ex vivo native cornea. The model that most resembled the rheological behavior of the native cornea was a fibrin–0.1% agarose concentration nanostructured construct. In addition, this artificial cornea model displayed optimal levels of transparency, similar to the native tissue. All these properties indicate that the fibrin–0.1% agarose concentration nanostructured construct might serve as an adequate candidate for the generation of an artificial complete cornea, not only for transplanting use but also for conducting pharmaceutical testing and biomedical research.

To determine the UV absorbance of a bioengineered human corneal stroma construct based on fibrin and fibrin-agarose scaffolds in the 240-400 nm range.Three types of artificial substitutes of the human corneal stroma were developed by tissue engineering using fibrin and fibrin with 0.1% and 0.2% agarose scaffolds with human keratocytes immersed within. After 28 days of culture, the UV absorbance of each sample was determined using a spectrophotometer. The thickness of corneal stroma samples was determined by light microscope.For all the 3 types of corneal stroma substitutes studied, the range of the UV absorbance values was similar to that of the native human corneal stroma, although the fibrin with 0.1% agarose stroma substitute had the best UV filtering properties. The higher UV absorbance of the artificial substitute of the human corneal stroma was in the UV-B and -A ranges, suggesting that these artificial tissues could have potential clinical usefulness and proper UV light-absorption capabilities.Our data suggest that the bioengineered human corneal substitute of fibrin with 0.1% agarose is an effective absorber of harmful UV radiation and could therefore be potentially useful.

Journal Article; Correction: doi: 10.1371/journal.pone.0146205. PURPOSE Tissues and biomaterials used for corneal surface repair require fulfilling specific optical standards prior to implantation in the patient. However, there is not a feasible evaluation method to be applied in clinical or Good Manufacturing Practice settings. In this study, we describe and assess an innovative easy-applied photographic-based method (PBM) for measuring functional optical blurring and transparency in corneal surface grafts. METHODS Plastic compressed collagen scaffolds (PCCS) and multilayered amniotic membranes (AM) samples were optically and histologically evaluated. Transparency and image blurring measures were obtained by PBM, analyzing photographic images of a standardized band pattern taken through the samples. These measures were compared and correlated to those obtained applying the Inverse Adding-Doubling (IAD) technique, which is the gold standard method. RESULTS All the samples used for optical evaluation by PBM or IAD were histological suitable. PCCS samples presented transmittance values higher than 60%, values that increased with increasing wavelength as determined by IAD. The PBM indicated that PCCS had a transparency ratio (TR) value of 80.3 ± 2.8%, with a blurring index (BI) of 50.6 ± 4.2%. TR and BI obtained from the PBM showed a high correlation (ρ>|0.6|) with the diffuse transmittance and the diffuse reflectance, both determined using the IAD (p

Objectives To develop a customized CIELAB-based whiteness index for dentistry that accurately correlates to perception of tooth whiteness. Methods Four psychophysical experiments (PE1-4) were conducted by three panels of observers (OP1-3) under diffuse/0° observation/measuring conditions and under typical clinical viewing conditions. Nine whiteness indices (WI, Z %, WIC, WIO, W31, W64, W , WLAB, W *), two yellowness indices (YID1925, YIE313) and tint of white in the CIELAB color system ( T ) were compared with regard to their ability to measure the perceived whiteness of human teeth. Determination coefficient ( R 2 ) and ‘% wrong decision’ (%WD) method were used as direct measures of the quality of the indices for whiteness perception in dentistry. Results CIELAB-based whiteness index (WI D = 0.511 L * −2.324 a * −1.100 b *) was developed through optimization from the data obtained in PE1. The proposed WI D performed better than all the CIELAB and CIE1931 XYZ-based indices under laboratory and clinical conditions (only WIO was comparable to WI D in PE2 and PE4). Conclusion The validation experiments under laboratory and typical clinical conditions revealed that the proposed index WI D outperformed previous indices, being the only CIELAB-based index developed for evaluation of whiteness in dentistry.