Long Term Corneal Flattening After Corneal Crosslinking in Patients with Progressive Keratoconus.

Purpose: We evaluate the long-term visual, refractive, and keratometric outcomes after corneal crosslinking (CXL) in patients with progressive keratoconus (KC) and the incidence of an extreme corneal flattening effect. Settings: Oftalmosalud Institute of Eyes, Lima, Perú. Design: Retrospective cohort study. Methods: Forty-five eyes that underwent CXL with epithelial removal between June 2006 and September 2011. Data analysis was performed at preoperative evaluation, 1 year postoperatively, and at least 10 years or more postoperatively. Outcome measures included uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), and Scheimpflug (Pentacam) analysis. Progression was defined by an increase in steep keratometry (Ks) of 1.5D or greater between 2 examinations. Extreme flattening effect was defined as a decrease in K values equal to or greater than 5 diopters (D). Results: Mean follow-up time was 11 ± 1.07 years (range 10-13 years). There was a significant improvement in Ks, UCVA, CDVA, and spherical equivalent at the last visit. The overall rate of progression was 2.22% (1/45). Extreme flattening was observed in 15.5% (7/45) of the eyes, and this was associated with a loss of CDVA in 4.44% (2/45) of the eyes. One eye with corneal flattening of 11.5 D lost 7 lines of CDVA and required corneal transplantation. Conclusion: CXL is a safe and effective procedure to stop the progression of KC with a good overall long-term success rate. Extreme corneal flattening may be more common than commonly recognized, and severe corneal flattening associated with a decrease in CDVA may occur.

Unstable behavior of segmental ring under various pressures and its discrete element simulation.

In February 2012, a serious accident which resulted in five fatalities happened during a TBM-tunnel construction under the seabed in Japan. The cause of the accident appeared to be due to the Key-segment slipping out of the segment ring by the thrusting tailskin (wire brushes) of the TBM into the segment ring. This resulted in the collapse of the rings, causing the seabed ground and seawater to flow into the tunnel. We investigated how thin and thick segments without any circumferential joints behave under isotropic and anisotropic pressures using small-scale physical model. In the model tests, pressures were applied to the surroundings of the segment rings and the strains at each segment were measured in order to evaluate the damage. In addition, cases where lubrication on the contact area between the K- and B-segments was present or not were investigated and their discrete element simulations were also conducted.

Designing High-Affinity Peptides for Organic Molecules by Explicit Solvent Molecular Dynamics.

Short peptides offer a cheap alternative to antibodies for developing sensing units in devices for concentration measurement. We here describe a computational procedure that allows designing peptides capable of binding with high affinity a target organic molecule in aqueous or nonstandard solvent environments. The algorithm is based on a stochastic search in the space of the possible sequences of the peptide, and exploits finite temperature molecular dynamics simulations in explicit solvent to check if a proposed mutation improves the binding affinity or not. The procedure automatically produces peptides which form thermally stable complexes with the target. The estimated binding free energy reaches the 13 kcal/mol for Irinotecan anticancer drug, the target considered in this work. These peptides are by construction solvent specific; namely, they recognize the target only in the solvent in which they have been designed. This feature of the algorithm calls for applications in devices in which the peptide-based sensor is required to work in denaturants or under extreme conditions of pressure and temperature.

Analysis of labour accidents in tunnel construction and introduction of prevention measures.

At present, almost all mountain tunnels in Japan are excavated and constructed utilizing the New Austrian Tunneling Method (NATM), which was advocated by Prof. Rabcewicz of Austria in 1964. In Japan, this method has been applied to tunnel construction since around 1978, after which there has been a subsequent decrease in the number of casualties during tunnel construction. However, there is still a relatively high incidence of labour accidents during tunnel construction when compared to incidence rates in the construction industry in general. During tunnel construction, rock fall events at the cutting face are a particularly characteristic of the type of accident that occurs. In this study, we analysed labour accidents that possess the characteristics of a rock fall event at a work site. We also introduced accident prevention measures against rock fall events.

La morfología dental en contextos clínicos, antropológicos y forenses / Dental morphology in clinical, anthropological and forensic contexts

El propósito de este artículo es hacer una revisión de la literatura sobre los rasgos morfológicos dentales dentro de los contextos odontológico, antropológico y forense. Estos son empleados en la estimación de las relaciones biológicas entre poblaciones y relevantes en los problemas legales. Su naturaleza puede predisponer al desarrollo de procesos patológicos, de ahí la importancia de su conocimiento para el odontólogo general...

The purpose of this article is to review the literature on dental morphological traits within the dentistry, anthropological and forensic contexts. They are employed in the estimation of biological relations between populations and they are relevant to legal problems. Its nature may predispose the development of pathological processes, hence the importance of knowledge for the general dentist...

Atomic force microscopy based nanoassay: a new method to study α-Synuclein-dopamine bioaffinity interactions.

Intrinsically Disordered Proteins (IDPs) are characterized by the lack of well-defined 3-D structure and show high conformational plasticity. For this reason, they are a strong challenge for the traditional characterization of structure, supramolecular assembly and biorecognition phenomena. We show here how the fine tuning of protein orientation on a surface turns useful in the reliable testing of biorecognition interactions of IDPs, in particular α-Synuclein. We exploited atomic force microscopy (AFM) for the selective, nanoscale confinement of α-Synuclein on gold to study the early stages of α-Synuclein aggregation and the effect of small molecules, like dopamine, on the aggregation process. Capitalizing on the high sensitivity of AFM topographic height measurements we determined, for the first time in the literature, the dissociation constant of dopamine-α-Synuclein adducts.

Evaluation of milk powder quality by protein oxidative modifications.

The objective of the present research was to evaluate commercially available milk powders according to their protein oxidative modifications and antioxidant capacity, and to evaluate if these characteristics are related to physical quality parameters such as dispersibility or stability during storage. Fifteen commercially processed spray-dried milk powders were evaluated: 6 whole milk powders (WMP), 4 skim milk powders (SMP), and 5 infant formula powders (IFP). Protein oxidative status was measured as protein carbonyl (PC) content, dityrosine content, and extent of protein polymerization. The level of PC was slightly lower in SMP than in WMP, whereas IFP had more than twice as much PC as WMP (2.8 ± 0.4, 2.1 ± 0.2, and 6.5 ± 1.3 nmol/mg of protein for WMP, SMP, and IFP, respectively). No differences were detected in dityrosine accumulation. Although all the possible pairs of parameters were tested for correlations, we found that 4 parameters were linked: PC, whey content, protein aggregate level, and dispersibility. After 9 mo of storage at -20°C or room temperature, all milk samples were analyzed to evaluate changes in protein oxidative status (PC, dityrosine, and protein integrity) and related parameters. Compared with the initial condition, PC increased in all tested samples after 9 mo of storage at -20°C or at room temperature. Stored milk powders had increased PC and decreased dispersibility compared with prestorage levels. Our results highlight the importance of protein oxidative status in milk powder and its relationship to other related quality parameters, such as protein integrity and dispersibility. Our findings suggest that the understanding of such relationships could help in developing quality differentiation for different types of milk powders in the product market.

Prevalence of signs and symptoms of temporomandibular disorders (TMD) in patients wearing bimaxillary complete dentures, removable partial dentures and in students with natural dentition.

Temporomandibular Disorder (TMD) has attained a prominent role within the context of dental care due to its high prevalence. The aim of this study was to evaluate the prevalence of signs and symptoms of TMD in students at the State University of West of Paraná (UNIOESTE) with natural dentition, and in patients with removable partial dentures and double complete dentures. A total of 210 randomly selected individuals of both genders were evaluated, being divided into three groups: seventy students at the UNIOESTE with natural dentition (Group 1), seventy patients with removable partial dentures (Group 2) and seventy patients with bimaxillary complete dentures (Group 3). The data were collected by a single examiner using the American Academy of Orofacial Pain questionnaire for triage, where a single affirmative response to any of the situations mentioned was enough to carry out clinical evaluation. Kolmogorov Smirnov, Mann Whitney, Chi-Square, ANOVA and Tukey's statistical tests were performed. The most prevalent signs and symptoms of TMD in Group 1 were pain or difficulty in chewing or talking, perception of recent change in bite and deviations during the course of mandibular movements. In Group 2 they were perceptions of recent changes in the bite, deflections in the mandibular movements, presence of joint sounds, pain during excursive movements and muscle tenderness. The most prevalent signs and symptoms in Group 3 were limited to mouth opening and poor stability and retention of at least one of the prostheses. Group 3 also reported having received treatment for headaches or facial pain with a high prevalence. Group 2 had the highest prevalence of signs and symptoms. Prevalence was similar in Groups 1 and 3.

Prevalence of signs and symptoms of temporomandibular disorders (TMD) in patients wearing bimaxillary complete dentures, removable partial dentures and in students with natural dentition. / Prevalence of signs and symptoms of temporomandibular disorders (TMD) in patients wearing bimaxillary complete dentures, removable partial dentures and in students with natural dentition.

Temporomandibular Disorder (TMD) has attained a prominent role within the context of dental care due to its high prevalence. The aim of this study was to evaluate the prevalence of signs and symptoms of TMD in students at the State University of West of Paraná (UNIOESTE) with natural dentition, and in patients with removable partial dentures and double complete dentures. A total of 210 randomly selected individuals of both genders were evaluated, being divided into three groups: seventy students at the UNIOESTE with natural dentition (Group 1), seventy patients with removable partial dentures (Group 2) and seventy patients with bimaxillary complete dentures (Group 3). The data were collected by a single examiner using the American Academy of Orofacial Pain questionnaire for triage, where a single affirmative response to any of the situations mentioned was enough to carry out clinical evaluation. Kolmogorov Smirnov, Mann Whitney, Chi-Square, ANOVA and Tukeys statistical tests were performed. The most prevalent signs and symptoms of TMD in Group 1 were pain or difficulty in chewing or talking, perception of recent change in bite and deviations during the course of mandibular movements. In Group 2 they were perceptions of recent changes in the bite, deflections in the mandibular movements, presence of joint sounds, pain during excursive movements and muscle tenderness. The most prevalent signs and symptoms in Group 3 were limited to mouth opening and poor stability and retention of at least one of the prostheses. Group 3 also reported having received treatment for headaches or facial pain with a high prevalence. Group 2 had the highest prevalence of signs and symptoms. Prevalence was similar in Groups 1 and 3.

Interactions of iron-sulfur clusters with small peptides: insights into early evolution.

Favoring the stability of iron-sulfur clusters in hydrothermal vents could have been important for the origin of life. It has been postulated that small "nest" peptides with lengths between 3 and 6 residues could have been important to stabilize early iron-sulfur clusters. We present theoretical calculations exploring the sequence and conformational spaces of short peptides able to bind with high affinity the iron-sulfur cluster Fe(4)S(4). Our results indicate that it is unlikely to form stable complexes between Fe(4)S(4) and small peptides at the core of hydrothermal vents. The formation of these complexes is instead favored for peptides of at least 8 residues as they diffused together with the Fe(4)S(4) clusters toward lower temperature regions within the vent-associated temperature gradients.

Bioavailability of metal ions and evolutionary adaptation.

The evolution of life on earth has been a long process that began nearly 3,5 x 109 years ago. In their initial moments, evolution was mainly influenced by anaerobic environments; with the rise of O2 and the corresponding change in bioavailability of metal ions, new mechanisms of survival were created. Here we review the relationships between ancient atmospheric conditions, metal ion bioavailability and adaptation of metals homeostasis during early evolution. A general picture linking geochemistry, biochemistry and homeostasis is supported by the reviewed literature and is further illustrated in this report using simple database searches.

Designing Short Peptides with High Affinity for Organic Molecules: A Combined Docking, Molecular Dynamics, And Monte Carlo Approach.

We present a method for designing artificial receptors capable of binding with high affinity to a chosen target organic molecule. The primary sequence of the peptide is optimized to maximize its binding affinity. Our algorithm builds on a combination of molecular dynamics, semiflexible docking, and replica exchange Monte Carlo and performs simultaneous sampling in sequence and conformational spaces carefully selecting the degree of flexibility in the mutated peptides. The approach is used to design a decapeptide able to bind efavirenz. The calculated binding energy of the designed peptide (approximately -12 kcal/mol) was confirmed experimentally by fluorescence measurements. NMR spectroscopy confirmed the interactions between the peptide and the efavirenz molecule predicted by the algorithm.

Disociación entre las vías de acción bajo control voluntario e inducida por estímulos en la memoria de trabajo / Dissociation of will and stimuli driven routes to action in working memory

Las acciones voluntariamente controladas son definidas como aquellos comportamientos motores no inducidos directamente por un estímulo perceptual o cognitivo bien aprendido, seleccionados con la intención expresa de cumplir una meta. Investigamos el desempeño correspondiente a las vías de la acción inducida por estímulos y bajo control voluntario mediante una tarea visual de tiempo de reacción a un estímulo blanco así como a la interrupción del flujo temporal de estímulos. La ejecución concurrente de la tarea visual con una tarea verbal secundaria (span de dígitos) permitió observar una interferencia selectiva sobre las respuestas al estímulo ausente, las cuales suponen control ejecutivo, mientras que las respuestas inducidas por el estímulo no fueron afectadas por la tarea verbal concurrente [F(1,10) = 10,73, p = 0,008]. Los resultados sustentan la hipótesis de estudios neuropsicológicos previos de que las áreas prefrontales dorsolaterales y del cingulado anterior estarían selectivamente involucradas en las respuestas bajo control voluntario.

Estudo das biocompatibilidade do sulfatiazol em pó no tecido subcutâneo localmente anestesiado / Study of the biocompatibility of sulfathiazole powder in locally anesthetizhed subcutaneous tissue

O propósito desse estudo foi avaliar a biocompatibilidade do sulfatizol (ST) e sua absorção no tecido subcutâneo localmente anestesiado. Uma loja cirúrgica foi preparada no tórax ventral de 90 ratos Wistar machos para a colocação do ST e como sítios controles. Foram 3 grupos experimentais: grupo 1, ST somente, grupo 2, ST com prévia infiltração de lidocaína a 2 por cento, grupo 3, controle (Sham). A resposta tissular foi avaliada histologicamente aos 2, 10 e 30 dias. Observou-se que ST atua como um corpo estranho que interfere na cicatrização tecidual e que o agente anestésico retardou a absorção e aumento do dano tecidual. Histometricamente o grupo 2 apresentou áreas de reabsorção tecidual mais extensas quando comparado aos grupos 1 e 3 (p<0,05). Os resultados indicaram claramente que a combinação do ST com a solução anestésica local é mais prejudicial para os tecidos moles que o ST sozinho

Quiste dentígero: nuevos conceptos sobre su etiopatogenia / Dentigerous cyst new concepts about its etiopathogenesis

Aunque el quiste dentígero es el segundo quiste odontogénico más común, se desconoce su verdadera histogénesis. Se ha sugerido que existen dos tipos clínico-histopatológicos de quistes dentígeros: con un origen de desarrollo e inflamatorio. El propósito de este artículo fue presentar dos casos de grandes quistes dentígeros. Estos casos fueron usados para explicar la patogenia y el comportamiento de los dos tipos de quistes dentígeros, basados principalmente en los avances de la biología molecular disponible en la literatura

Quiste dentígero: nuevos conceptos sobre su etiopatogenia / Dentigerous cyst new concepts about its etiopathogenesis

Aunque el quiste dentígero es el segundo quiste odontogénico más común, se desconoce su verdadera histogénesis. Se ha sugerido que existen dos tipos clínico-histopatológicos de quistes dentígeros: con un origen de desarrollo e inflamatorio. El propósito de este artículo fue presentar dos casos de grandes quistes dentígeros. Estos casos fueron usados para explicar la patogenia y el comportamiento de los dos tipos de quistes dentígeros, basados principalmente en los avances de la biología molecular disponible en la literatura (AU)

Quiste dentigero: nuevos conceptos sobre su etiopatogenia

MONOGRAFIA presentada a la Sociedad Argentina de Cirugia y Traumatologia Buco Maxilofacial. Asociacion Odontologica Argentina

Quiste dentigero: nuevos conceptos sobre su etiopatogenia

MONOGRAFIA presentada a la Sociedad Argentina de Cirugia y Traumatologia Buco Maxilofacial. Asociacion Odontologica Argentina

Diente fantasma (Odontodisplasia) / Ghost tooth (Odontodysplasia)

La odontodisplasia regional es una malformacion dentaria no usual. Los dientes afectados muestran una distintiva apariencia clinica, radiografica e histologica. Se presenta un caso clinico en un paciente pediatrico con un diente permanente odontodisplasico, y se realiza una amplia revision de la literatura de esta patologia.