Interfacial activity and interfacial shear rheology of native ß-lactoglobulin monomers and their heat-induced fibers

Interfacial properties of native β-lactoglobulin monomers and their heat-induced fibers, of two different lengths, were investigated at pH 2, through surface tension measurements at water−air and water−oil interfaces and interfacial shear rheology at the water−oil interface. The applied heat treatment generates a mixed system of fibers with unconverted monomers and hydrolyzed peptides. The surface tension of this system at the water−air interface decreased more rapidly than the surface tension of native monomers, especially at short times (10⁻³ to 10²s). This behavior was not observed when the unconverted monomers and peptides were removed by dialysis. At the water−oil interface, the adsorption kinetics was much faster than at the water−air interface, with a plateau interfacial pressure value reached after 1 h of adsorption. For all the systems, interfacial shear rheology showed the formation of a highly elastic interface, with solid-like behavior at 1−10³ s time scales. The highest modulus was observed for the long fibers and the lowest for the native monomers. Creep−compliance curves in the linear regime could be reduced to a single master curve, showing similar spectra of relaxation times for all investigated systems. Upon large deformations, the interfaces formed with long fibers showed the most rigid and fragile behavior. This rigidity was even more pronounced in the presence of unconverted monomers

Concept on self-assembly and structure of globular protein fluids

Globular proteins are ubiquitous in our daily life. Not only they are naturally present in the biological matter, they also offer many possibilities to adjust the nutritional and flow properties of fluids or to design drug vehicles [1]. Globular protein systems interact through short range attractive forces; and the interaction between them may lead the system to form aggregates through self-assembling process. Since such biological monomers are complex systems, their aggregation process is most of the time out of control. The current main conceptual framework to describe that process is based on the idea that the monomers may self-assemble through a diffusion and reaction mechanism known as DLA for diffusion limited aggregation, and RLA for reaction limited aggregation respectively [2]. Beta-lactoglobulin (blg) solution gives, after heat-induced denaturation, a suspension of polydisperse aggregates as predicted by the random aggregation concept. Therefore, the transition from native blg to denatured blg aggregate suspension leads to complex correlation with the flow behavior [3]. Although the dependency of the aggregation process to physicochemical factors like, ionic strength, pH, temperature and concentration has been intensively investigated, it still remains much to do to control the aggregate polydispersity via self-assembling process. The composition of the raw product, thermal processing, pH and entropy instability during the aggregation process, are some of the factors influencing the polydispersity of the aggregates. We use different techniques such as SAXS/USAXS, LS, SEM, CSLM and image analysis methods to characterize thoroughly the structure of globular protein aggregates formed after heat-induced denaturation at different experimental conditions [4]. Whether these aggregates are in solution or entrapped by gelation, we do think that investigating their structure will provide us with relevant information to solve the issue related to their formation. Please click Additional Files below to see the full abstract

Effects of surface-active block copolymers with oxyethylene and fluoroalkyl side chains on the antifouling performance of silicone-based films

Block copolymers made from a poly(dimethyl siloxane) (Si) and a poly(meth)acrylate carrying oxyethylene (EG) or fluoroalkyl (AF) side chains were synthesized and incorporated as surface-active components into a silicone matrix to produce cross-linked films with different surface hydrophilicity/phobicity. Near-edge X-ray absorption fine structure (NEXAFS) studies showed that film surfaces containing Si-EG were largely populated by the siloxane, with the oxyethylene chains present only to a minor extent. In contrast, the fluorinated block was selectively segregated to the polymer–air interface in films containing Si-AF as probed by NEXAFS and X-ray photoelectron spectroscopy (XPS) analyses. Such differences in surface composition were reflected in the biological performance of the coatings. While the films with Si-EG showed a higher removal of both Ulva linza sporelings and Balanus amphitrite juveniles than the silicone control, those with Si-AF exhibited excellent antifouling properties, preventing the settlement of cyprids of B. amphitrite

Effect of Septoplasty on Voice Quality: A Prospective-Controlled Trial

Objectives. The purpose is to investigate effect of septoplasty and widened nasal patency on voice quality. Methods. Fifty patients who undergone septoplasty were included in the study. Thirty-three people who had similar age and distribution were enrolled as control group. Before and 1 and 3 months after surgery, anterior rhinomanometry, voice analysis by Multi-Dimensional Voice Program, and spectrographic analysis were performed to patients. The recordings of /a/ vowel were used to evaluate average fundamental frequency (F0), jitter percent, and shimmer percent. In spectrographic analyses, F3–F4 values for the vowels /i, e, a, o, and u/, nasal formant frequencies of the consonants /m/ and /n/ in the word /mini/, and 4 formant frequencies (F1, F2, F3, and F4) for nasalized /i/ vowel following a nasal consonant /n/ in the word /mini/ were compared. The differences in nasal resonance were evaluated. All patients were asked whether change in their voices after the surgery. Preoperative and postoperative voice parameters and anterior rhinomanometry results were compared separately with the control group as well as in the patient group itself. Results. Preoperative total nasal resistance (TNR) values of patients were higher than the control group (P=0.001). TNR values of patients measured one day before surgery and after surgery in the 1st and 3rd months were different and these differences were significant statistically (P=0.001). There was no significant difference between the voice analysis parameters in preoperative, postoperative 1st, and 3rd months. As a result of their subjective reviews, 12 patients (36%) noted their voices were better than before surgery and 20 patients (61%) noted no change before and after surgery. Conclusion. Providing widened nasal cavity has no effect on voice quality

Blood mRNA expression profiles of autophagy, apoptosis, and hypoxia markers on blood cardioplegia and custodiol cardioplegia groups

Introduction: Blood cardioplegia (BC) and Custodiol cardioplegia (CC) have been used for a long time in open heart surgery and are highly effective solutions. The most controversial issue among these two is whether there is any difference between them regarding myocardial damage after ischemia surgery. In this study, autophagy, apoptosis, and hypoxia markers were investigated and that way we evaluated the differences between BC and CC patients

Comparação de Soluções Cardioplégicas em Cirurgia de Revascularização Miocárdica sobre Mecanismos de Autofagia e Apoptose

Resumo Fundamento A doença arterial coronariana (DAC) devido à isquemia miocárdica causa perda permanente de tecido cardíaco. Objetivos Nosso objetivo foi demonstrar o possível dano ao miocárdio em nível molecular através dos mecanismos de autofagia e apoptose em pacientes submetidos à cirurgia de revascularização miocárdica. Métodos Um grupo recebeu uma solução de cardioplegia Custodiol e o outro grupo uma solução de cardioplegia sanguínea. Duas amostras miocárdicas foram coletadas de cada paciente durante a operação, imediatamente antes da parada cardíaca e após a liberação do pinçamento aórtico. Foram avaliadas as expressões de marcadores de autofagia e apoptose. O nível de significância estatística adotado foi de 5%. Resultados A expressão do gene BECLIN foi significativa nos tecidos miocárdicos do grupo CS (p=0,0078). Os níveis de expressão dos genes CASPASE 3, 8 e 9 foram significativamente menores no grupo CC. Os níveis pós-operatórios de TnT foram significativamente diferentes entre os grupos (p=0,0072). As expressões dos genes CASPASE 8 e CASPASE 9 foram semelhantes antes e depois do pinçamento aórtico (p=0,8552, p=0,8891). No grupo CC, os níveis de expressão gênica de CASPASE 3, CASPASE 8 e CASPASE 9 não foram significativamente diferentes em amostras de tecido coletadas após pinçamento aórtico (p=0,7354, p=0,0758, p=0,4128, respectivamente). Conclusões Com nossos achados, acreditamos que as soluções CC e CS não apresentam diferença significativa em termos de proteção miocárdica durante as operações de by-pass

Epidemiology of pemphigus in Turkey: One-year prospective study of 220 cases

Pemphigus is a group of rare and life-threatening autoimmune blistering diseases of the skin and mucous membranes. Although they occur worldwide, their incidence shows wide geographical variation, and prospective data on the epidemiology of pemphigus are very limited. Objective of this work is to evaluate the incidence and epidemiological and clinical features of patients with pemphigus in Turkey. All patients newly diagnosed with pemphigus between June 2013 and June 2014 were prospectively enrolled in 33 dermatology departments in 20 different provinces from all seven regions of Turkey. Disease parameters including demography and clinical findings were recorded. A total of 220 patients were diagnosed with pemphigus during the 1-year period, with an annual incidence of 4.7 per million people in Turkey. Patients were predominantly women, with a male to female ratio of 1:1.41. The mean age at onset was 48.9 years. Pemphigus vulgaris (PV) was the commonest clinical subtype (n=192; 87.3%), followed by pemphigus foliaceus (n=21; 9.6%). The most common clinical subtype of PV was the mucocutaneous type (n=83; 43.2%). The mean Pemphigus Disease Area Index was 28.14±22.21 (mean ± Standard Deviation).  The incidence rate of pemphigus in Turkey is similar to the countries of South-East Europe, higher than those reported for the Central and Northern European countries and lower than the countries around the Mediterranean Sea and Iran. Pemphigus is more frequent in middle-aged people and is more common in women. The most frequent subtype was PV, with a 9-fold higher incidence than pemphigus foliaceus.   </p