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Understanding the determinants of antibody specificity is one of the challenging tasks in antibody development. Monospecific antibodies are still dominant in approved antibody therapeutics but there is a significant body of work to show that multispecific antibodies can increase the overall therapeutic effect. Dual-specific or "Two-in-One" antibodies can bind to two different antigens separately with the same antigen-binding site as opposed to bispecifics, which simultaneously bind to two different antigens through separate antigen-binding units. These nonstandard dual-specific antibodies were recently shown to be promising for new antibody-based therapeutics. Here, we physicochemically and structurally analyzed six different antibodies of which two are monospecific and four are dual-specific antibodies derived from monospecific templates to gain insight about dual-specificity determinants. These dual-specific antibodies can target both human epidermal growth factor receptor 2 and vascular endothelial growth factor at different binding affinities. We showed that a particular region of clustered Vernier zone residues might play key roles in gaining dual specificity. While there are minimal intramolecular interactions between a certain Vernier zone region, namely LV4 and LCDR1 of monospecific template, there is a significant structural change and consequently close contact formation between LV4-LCDR1 loops of derived dual-specific antibodies. Although Vernier zone residues were previously shown to be important for humanization applications, they are mostly underestimated in the literature. Here, we also aim to resurrect Vernier zone residues for antibody engineering efforts.
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Anticorpos Biespecíficos/química , Antígenos/química , Antineoplásicos Imunológicos/química , Região Variável de Imunoglobulina/química , Receptor ErbB-2/química , Fator A de Crescimento do Endotélio Vascular/química , Sequência de Aminoácidos , Anticorpos Biespecíficos/genética , Anticorpos Biespecíficos/metabolismo , Afinidade de Anticorpos , Especificidade de Anticorpos , Antígenos/genética , Antígenos/imunologia , Antineoplásicos Imunológicos/metabolismo , Sítios de Ligação , Sítios de Ligação de Anticorpos/genética , Humanos , Região Variável de Imunoglobulina/genética , Região Variável de Imunoglobulina/metabolismo , Simulação de Dinâmica Molecular , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Engenharia de Proteínas/métodos , Domínios e Motivos de Interação entre Proteínas , Receptor ErbB-2/antagonistas & inibidores , Receptor ErbB-2/genética , Receptor ErbB-2/imunologia , Alinhamento de Sequência , Homologia Estrutural de Proteína , Termodinâmica , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/imunologiaRESUMO
PURPOSE: The aim of this study was to compare in vitro fracture strengths (FSs) of metal- and fiber-reinforced frameworks of resin-bonded bridges and to evaluate stress distribution with finite element analysis (FEA). MATERIALS AND METHODS: Totally 80 extracted maxillary central and maxillary canine teeth were used for in vitro part of this study as two groups; metal-reinforced framework (n = 20) [(metal-supported resin-bonded bridge (MR-RB)] and fiber-reinforced frameworks (n = 20) [fiber-reinforced resin-bonded bridge (FR-RB) were prepared for three unit resin-bonded bridges. All bridges were loaded from lateral pontic at 1 mm/min crosshead speed and fracture values were recorded. Mann-Whitney U-test was used for statistical analysis, and fracture patterns were evaluated visually. FEA was carried out in the second part of the study, and stress distribution of MR-RB and FR-RB structures was analyzed using one of the models from in vitro specimens as main model. RESULTS: The mean FSs of MR-RB and FR-RB were 637.47 ± 151.91 N and 224.86 ± 80.97 N, respectively. Fiber-reinforced specimens were found to distribute stress more homogeneous and connectors in each framework were the regions where stress concentrated mostly. CONCLUSION: In vitro FSs of MR-RB and the stress concentration of the point that the forces were applied were higher as compared to other parts of the restoration. Furthermore, in contrast to FR-RB specimens, retainer tooth fractures were observed in MR-RB specimens.
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Resinas Compostas/química , Análise do Estresse Dentário/métodos , Prótese Adesiva , Cimentos de Resina/química , Fraturas dos Dentes , Materiais Dentários , Análise de Elementos Finitos , Humanos , Teste de MateriaisRESUMO
Objective: Infective endocarditis incidence has been rising in recent years, with high mortality. Risk factors such as underlying heart diseases, chronic diseases, healthcare-associated infections, advanced age, and intravenous (IV) drug use have gained importance in the incidence, the treatment approach, and the disease course. The aim of this study is to contribute to Türkiye's data on infective endocarditis epidemiology and risk factors. Materials and Methods: This study examined risk factors, diagnostic and treatment approaches, and prognosis of infective endocarditis cases at Pamukkale University Faculty of Medicine Hospital. It was carried out prospectively for 28 months. Results: During this period, 67 endocarditis cases were detected in 65 patients. Among cardiac diseases, the rate of congenital heart diseases (41%), degenerative heart diseases (37%), and acute rheumatic fever (ARF) related valvular heart disease (31%) were found to be high. Hospitalization in the last six months (53.7%), history of cardiac surgery (41.8%), use of IV catheters (22.4%), hemodialysis (14.9%) and IV drug use (7.5%) were also determined. Staphylococci, streptococci, and enterococci were the primary agents. The most used empirical treatments were ampicillin, ampicillin-sulbactam, and gentamicin. Natural valve endocarditis was most determined. Surgical treatment was applied in 56.7% of endocarditis cases. Septic embolism and cardiac failure were the most common complications. Conclusion: This study's findings regarding the epidemiology and prognosis of infective endocarditis pointed out that it is still a disease with a high mortality rate.
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BACKGROUND: Spinal orthosis applications are preferred for conservative treatment of adolescent idiopathic scoliosis, and holistic biomechanical approaches are recommended. METHODS: This was single-blind, prospective, randomized, controlled study. It included 42 patients (29 females/13 males) aged 10-18 years with adolescent idiopathic scoliosis, Cobb angle of 20°-45°, who were deemed suitable for spinal orthosis use. Patients were randomly divided into two groups: control, spinal orthosis group (n = 21), and insoles and spinal orthosis group (n = 21). All participants used spinal orthoses for 3 months. This study evaluated the functional capacities, quality of life, balance, and plantar pressures of the participants. The evaluations were repeated after 1 week, and 3 months following spinal orthosis application. FINDINGS: Statistically significant difference and positive effect were observed in Cobb angle (p = 0.008; p = 0.878, respectively), right total (p = 0.037; p = 0.193, respectively), left total (p = 0.037; p = 0.193, respectively), left rearfoot (p = 0.002; p = 0.708, respectively), and right forefoot plantar pressure (p = 0.001; p = 0.739, respectively) in participants in insoles and spinal orthosis group compared with those in the control group. Statistically significant differences and positive effects were observed in swing length (p = 0.001; p = 0.053, respectively) and functional capacity (p = 0.005; p = 0.220, respectively), which are parameters related to postural balance. No change was found in quality of life of either group (p > 0.05). INTERPRETATION: Insoles may have positive impact on functional capacity, balance, and plantar pressure during long-term follow-up in individuals with scoliosis. Therefore, the evaluation of foot plantar pressure in individuals with scoliosis is recommended, and personalized insoles may be a beneficial option.
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Cifose , Escoliose , Masculino , Feminino , Humanos , Adolescente , Escoliose/terapia , Estudos Prospectivos , Qualidade de Vida , Método Simples-Cego , Aparelhos OrtopédicosRESUMO
The aim of the present study was to evaluate the environmental impacts of hazelnut cultivation in Ordu province of Türkiye, which ranks first in world hazelnut production. Thus, a cradle-to-gate life cycle assessment (LCA) was implemented to analyze the environmental impact potentials determined as acidification potential (AP), eutrophication potential (EP), and global warming potential (GWP). Additionally, energy use efficiency and economic analysis were identified. Data were collected from fifteen farmers cultivating in the same region and performing the same cultural practices by conducting a face-to-face questionnaire during the period of 2019-2020. LCA results showed that all environmental impacts and energy use of hazelnut production in the region were dominated by synthetic fertilizer. According to the results of the economic analysis, human labor had the highest share (52.7 % as a minimum) with 6.2 TRY kg-1 and 5550.0 TRY ha-1, although it was not included in the environmental impact category. Harvesting had the largest share in economic costs, but it was the most challenging cultural practice as it was carried out under difficult conditions (slope up to 70 %, hot weather) and depended only on human labor. This study provides a basis for future studies and recommends solutions for agricultural sustainability in hazelnut production. The foremost step taken should be to use fertilizer according to soil analysis and to encourage organic fertilizer use. Future studies should examine the relationship between fertilizer use and hazelnut yield. Also, the use of manpower tools without fossil fuels could overcome the challenges as an environmentally friendly solution for harvesting.
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Corylus , Humanos , Animais , Fertilizantes , Meio Ambiente , Agricultura/métodos , Estágios do Ciclo de VidaRESUMO
Affinity and stability are crucial parameters in antibody development and engineering approaches. Although improvement in both metrics is desirable, trade-offs are almost unavoidable. Heavy chain complementarity determining region 3 (HCDR3) is the best-known region for antibody affinity but its impact on stability is often neglected. Here, we present a mutagenesis study of conserved residues near HCDR3 to elicit the role of this region in the affinity-stability trade-off. These key residues are positioned around the conserved salt bridge between VH-K94 and VH-D101 which is crucial for HCDR3 integrity. We show that the additional salt bridge at the stem of HCDR3 (VH-K94:VH-D101:VH-D102) has an extensive impact on this loop's conformation, therefore simultaneous improvement in both affinity and stability. We find that the disruption of π-π stacking near HCDR3 (VH-Y100E:VL-Y49) at the VH-VL interface cause an irrecoverable loss in stability even if it improves the affinity. Molecular simulations of putative rescue mutants exhibit complex and often non-additive effects. We confirm that our experimental measurements agree with the molecular dynamic simulations providing detailed insights for the spatial orientation of HCDR3. VH-V102 right next to HCDR3 salt bridge might be an ideal candidate to overcome affinity-stability trade-off.
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Regiões Determinantes de Complementaridade , Cadeias Pesadas de Imunoglobulinas , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias Pesadas de Imunoglobulinas/química , Regiões Determinantes de Complementaridade/genética , Regiões Determinantes de Complementaridade/química , Afinidade de AnticorposRESUMO
Recombinant protein-based SARS-CoV-2 vaccines are needed to fill the vaccine equity gap. Because protein-subunit based vaccines are easier and cheaper to produce and do not require special storage/transportation conditions, they are suitable for low-/middle-income countries. Here, we report our vaccine development studies with the receptor binding domain of the SARS-CoV-2 Delta Plus strain (RBD-DP) which caused increased hospitalizations compared to other variants. First, we expressed RBD-DP in the Pichia pastoris yeast system and upscaled it to a 5-L fermenter for production. After three-step purification, we obtained RBD-DP with > 95% purity from a protein yield of > 1 g/L of supernatant. Several biophysical and biochemical characterizations were performed to confirm its identity, stability, and functionality. Then, it was formulated in different contents with Alum and CpG for mice immunization. After three doses of immunization, IgG titers from sera reached to > 106 and most importantly it showed high T-cell responses which are required for an effective vaccine to prevent severe COVID-19 disease. A live neutralization test was performed with both the Wuhan strain (B.1.1.7) and Delta strain (B.1.617.2) and it showed high neutralization antibody content for both strains. A challenge study with SARS-CoV-2 infected K18-hACE2 transgenic mice showed good immunoprotective activity with no viruses in the lungs and no lung inflammation for all immunized mice.
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Vacinas contra COVID-19 , COVID-19 , Animais , Humanos , Camundongos , SARS-CoV-2/genética , COVID-19/prevenção & controle , Camundongos Transgênicos , Saccharomyces cerevisiae , Anticorpos Antivirais , Anticorpos NeutralizantesRESUMO
This study aims to assess the environmental impacts and the energy efficiency of organic and conventional vegetable production in Palas Basin, Kayseri, Turkey. Three organic and three conventional farmers representing the vegetable production in the region participated in face-to-face questionnaires. Life cycle assessment (LCA) was implemented to assess the global warming potential (GWP), eutrophication potential (EP), acidification potential (AP), and energy use, which were selected as environmental impact potentials. Additionally, the environmental risk assessment was conducted to understand the impact of pesticide use in the region. Six farmers were investigated individually, and it was found that all of the farmers had a common cultivation calendar, but there were differences in the application. Particularly, mineral fertilizer use and irrigation were excessive in some agricultural practices. Although the use of N- and P-based mineral fertilizers was one of the main differences between organic and conventional farming, irrigation was a common practice. Irrigation, the most influential practice, elevated not only water consumption but also EP, AP, and GWP as a result of electricity consumption by electrical pumps. Electricity consumption from irrigation contributed to the GWP most, and this value was in the range of 45%-95%. Mineral fertilizer use covered up to 40% of the EP, 31% of the GWP, and 37% of the AP for conventional farmers. Three different scenarios were developed to reduce the environmental impacts of the use of excessive mineral fertilizer and irrigation. The developed scenarios recommended the reductions by 38%, 44%, 25%, and 60% in GWP, EP, AP, and total energy inputs, respectively. This study demonstrates that LCA is beneficial in determining the environmental impact of hotspots in vegetable production and allows the development of different solutions to mitigate environmental impacts for agricultural sustainability. Integr Environ Assess Manag 2022;18:1733-1746. © 2022 SETAC.
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Fertilizantes , Verduras , Animais , Meio Ambiente , Agricultura , Estágios do Ciclo de VidaRESUMO
Single chain antibody fragments (scFvs) are favored in diagnostic and therapeutic fields thanks to their small size and the availability of various engineering approaches. Linker between variable heavy (VH) and light (VL) chains of scFv covalently links these domains and it can affect scFv's bio-physical/chemical properties and in vivo activity. Thus, scFv linker design is important for a successful scFv construction, and flexible linkers are preferred for a proper pairing of VH-VL. The flexibility of the linker is determined by length and sequence content and glycine-serine (GS) linkers are commonly preferred for scFvs based on their highly flexible profiles. Despite the advantage of this provided flexibility, GS linkers carry repeated sequences which can cause problems for PCR-based engineering approaches and immunogenicity. Here, two different linkers, a repetitive GS linker and an alternative non-repetitive linker with similar flexibility but lower immunogenicity are employed to generate anti-Vascular Endothelial Growth Factor scFvs derived from bevacizumab. Our findings highlight a better in vitro profile of the non-repetitive linker such as a higher monomer ratio, higher thermal stability while there was no significant difference in in vivo efficacy in a zebrafish embryonic angiogenesis model. This is the first study to compare in vivo efficacy of scFvs with different linkers in a zebrafish model.
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Região Variável de Imunoglobulina , Peixe-Zebra , Animais , Anticorpos Monoclonais , Fragmentos de Imunoglobulinas/química , Região Variável de Imunoglobulina/química , Fatores de Crescimento do Endotélio VascularRESUMO
This study intended to analyze microcracks and fractographic markings on the surface of all ceramic crowns after milling and compare the fracture loads. 90 crowns were manufactured from two feldspathic (Priticrown-Pr and Vita Mark II-Vi) and a lithium disilicate (EmaxCAD-Em) blocks (n = 30). Two groups (n = 15) were prepared for each ceramic. In the first group, crowns were analyzed twice via the fluorescent penetrant method for microcrack detection, after the manufacturing process and thermal cycles. The load to fracture test was applied at a crosshead speed of 0.5 mm/min until catastrophic failure. Second group crowns were directly cemented onto the Co-Cr dies following the manufacturing process and loaded to fracture. Fractographic markings were analyzed through scanning electron microscope. Spearman correlation analysis, Kruskal-Wallis H test, Mann-Whitney U test, and Wilcoxon Signed Rank test were applied (α = .05). Fracture loads of Em crowns were higher than other groups (p < .05), with and without the aging procedure. Except for second group Pr (r = -.532), no significant relationship was found between microcrack numbers and fracture loads (p > .05). Thermal cycling did not affect microcrack numbers and fracture loads (p > .05). Tooth-shaped multilayered Pr blocks did not provide an advantage in terms of microcrack and fracture loads.
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Desenho Assistido por Computador , Coroas , Cerâmica , Análise do Estresse Dentário , Teste de MateriaisRESUMO
This study intended to compare the repair bond strength of computer-aided design/computer-aided manufacturing (CAD/CAM) blocks consisting of resin and feldspathic ceramics following different surface treatments using the microtensile bond strength (µTBS) test. Ten specimens were prepared with 4 mm height for Vita Enamic (VE), Lava Ultimate (LU), Vita Mark II (VM), and thermocycled (10,000 cycle, 5-55°C). Each material was categorized into one of five subgroups according to following surface treatments: (a) bur grinding (BG), (b) hydrofluoric acid etching (HF), (c) neodymium-doped yttrium aluminum garnet (Nd:YAG or NY), (d) erbium-doped yttrium aluminum garnet (Er:YAG or EY), and (e) erbium, chromium-doped yttrium, scandium, gallium, and garnet (Er,Cr:YSGG or ECY) laser conditioning. After surface treatment procedures, specimens were properly restored to 4 mm high with a micro-hybrid composite resin. Bar specimens (1 × 1 × 8 mm) were obtained using a low-speed cutting machine and then thermocycled (10,000 cycle, 5-55°C). The µTBS was tested at 1 mm/min crosshead speed, and failure modes were evaluated. Data were analyzed with two-way ANOVA and post hoc Tukey tests. LU-BG showed significantly higher µTBS (32.94 ± 5.80 MPa) compared to LU-laser groups (p < .05). VE-BG showed significantly higher µTBS (22.06 ± 4.26 MPa) compared to other VE groups (p < .05). Among the laser groups, the NY laser produced the lowest (p < .05) µTBS for LU (13.42 ± 3.44 MPa) and VE (2.27 ± 0.85 MPa), while EY showed the highest (p < .05). Laser-treated VM groups were all prefailured. VM-HF produced a higher µTBS (18.73 ± 3.75 MPa) than VM-BG (5.05 ± 1.76 MPa) (p < .05).
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INTRODUCTION: In the presence of asymptomatic bacteriuria (ASB) before the urological procedure, the duration of antimicrobial treatment is controversial. This study aims to evaluate whether a short course of antimicrobial therapy is safe and effective in cases with ASB before urological procedures. METHODOLOGY: We retrospectively reviewed adult patients who had ASB before undergoing several urological procedures between 2011 and 2019. The patients received a single dose of an appropriate parenteral antibiotic, determined by antimicrobial sensitivity testing, 30 to 60 minutes before the urological procedure. If a urinary catheter was placed post-procedure, a second dose was given. RESULTS: A total of 293 patients who had ASB before undergoing several urological procedures were included in the study. The total number of procedures was 328. Female/male ratio was 92 (31.4%)/201 (68.6%). The mean age was 63.7 ± 14.9 years. The most common isolated microorganisms were Escherichia coli (155 [47%]), Klebsiella pneumoniae (38 [11.6%]), and Pseudomonas aeruginosa (28 [8.5%]). The most common antimicrobial used was ertapenem. A second dose antimicrobial was given for 290 procedures due to a urinary catheter after a urological procedure. The mean hospitalization time was 3.97 ± 3.42 days. None of the patients developed infectious complications. CONCLUSIONS: This study has demonstrated that a single dose of parenteral antimicrobial drug administered 30-60 minutes before the urologic procedures and a second dose in the presence of a post-procedure catheter, was adequate to prevent post-procedure septicemia and urinary tract infection.
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Antibacterianos/administração & dosagem , Bacteriúria/tratamento farmacológico , Procedimentos Cirúrgicos Urológicos , Bacteriúria/microbiologia , Esquema de Medicação , Ertapenem/administração & dosagem , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Cuidados Pré-Operatórios , Estudos Retrospectivos , TurquiaRESUMO
Centromeric loci of chromosomes are defined by nucleosomes containing the histone H3 variant CENP-A, which bind their DNA termini more permissively than their canonical counterpart, a feature that is critical for the mitotic fidelity. A recent cryo-EM study demonstrated that the DNA termini of CENP-A nucleosomes, reconstituted with the Widom 601 DNA sequence, are asymmetrically flexible, meaning one terminus is more clearly resolved than the other. However, an earlier work claimed that both ends could be resolved in the presence of two stabilizing single chain variable fragment (scFv) antibodies per nucleosome, and thus are likely permanently bound to the histone octamer. This suggests that the binding of scFv antibodies to the histone octamer surface would be associated with CENP-A nucleosome conformational changes, including stable binding of the DNA termini. Here, we present computational evidence that allows to explain at atomistic level the structural rearrangements of CENP-A nucleosomes resulting from the antibody binding. The antibodies, while they only bind the octamer façades, are capable of altering the dynamics of the nucleosomal core, and indirectly also the surrounding DNA. This effect has more drastic implications for the structure and the dynamics of the CENP-A nucleosome in comparison to its canonical counterpart. Furthermore, we find evidence that the antibodies bind the left and the right octamer façades at different affinities, another manifestation of the DNA sequence. We speculate that the cells could use induction of similar allosteric effects to control centromere function.
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Proteína Centromérica A/química , DNA/ultraestrutura , Heterocromatina/ultraestrutura , Histonas/química , Nucleossomos/ultraestrutura , Sequência de Aminoácidos , Pareamento de Bases , Sítios de Ligação , Proteína Centromérica A/genética , Proteína Centromérica A/metabolismo , Regiões Determinantes de Complementaridade/química , Regiões Determinantes de Complementaridade/metabolismo , DNA/genética , DNA/metabolismo , Heterocromatina/genética , Heterocromatina/metabolismo , Histonas/genética , Histonas/metabolismo , Humanos , Modelos Moleculares , Simulação de Dinâmica Molecular , Conformação de Ácido Nucleico , Nucleossomos/genética , Nucleossomos/metabolismo , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Anticorpos de Cadeia Única/química , Anticorpos de Cadeia Única/metabolismoRESUMO
This study investigated the effects of fumaric acid on push-out bond strength when applied to dentin surfaces and fiber posts. The root canals of 60 mandibular premolar teeth were instrumented and obturated. After removing two thirds of filling material, teeth were prepared according to six randomized groups (n = 10/group) defined by two fiber post surface treatments (0.7% fumaric acid or 9% hydrofluoric acid) and three dentin conditioning treatments [control (no conditioning); 17% ethylenediamine tetraacetic acid (EDTA); or 0.7% fumaric acid]. After fiber post-cementation, three 1-mm thick discs were obtained from each tooth by transverse sectioning, and each disc underwent push-out bond strength testing. Data were analyzed with a one-way analyses of variance (anova) and t tests; p < .05 was considered statistically significant. Failure modes were determined by stereomicroscopy, and the surface characteristics of dentin and fiber posts were observed by scanning electron microscopy. Push-out bond strength was greater for the group in which the post surface treated with hydrofluoric acid and the dentin surface treated with fumaric acid than the nontreated dentin and hydrofluoric acid-treated post group (p < .05). There were no significant differences between other comparison pairs (p > .05). A combination of fumaric acid dentin conditioning and hydrofluoric acid fiber post treatment strengthened the bonding ability of fiber posts.
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Colagem Dentária , Técnica para Retentor Intrarradicular , Cavidade Pulpar , Dentina , Fumaratos , Humanos , Teste de Materiais , Cimentos de ResinaRESUMO
Antibodies are specialized proteins generated by immune system for high specificity and affinity binding to target antigens. Because of their essential roles in immune system, antibodies have been successfully developed and engineered as biopharmaceuticals for treatment of various diseases. Analysis of antibody-protein interactions is always required to get detailed information on effectivity of such antibody-based therapeutics. Although physicochemical rules cannot be generalized for every antibody-protein interaction, there are some features which should be taken into account during antibody development and engineering efforts. In this chapter, physicochemical analysis of antibody paratope-protein epitope interactions will be discussed to highlight important characteristics. First, paratope and non-paratope regions of antibodies will be described and important roles of these regions on binding and biophysical features of antibodies will be discussed. Then, general features of epitope regions of protein antigens will be introduced along with several computational/experimental tools to identify them. Lastly, a rising star of antibody biopharmaceuticals, nanobodies, will be described to show importance of next-generation antibody fragment based biopharmaceuticals in drug development.
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Anticorpos/uso terapêutico , Sítios de Ligação de Anticorpos/efeitos dos fármacos , Epitopos/química , Engenharia de Proteínas/métodos , Anticorpos de Domínio Único/química , Anticorpos/química , Afinidade de Anticorpos , Especificidade de Anticorpos , Regiões Determinantes de Complementaridade/química , Regiões Determinantes de Complementaridade/imunologia , Mapeamento de Epitopos , Epitopos/imunologia , Humanos , Imunoglobulina G/química , Imunoglobulina G/imunologia , Neoplasias/imunologia , Neoplasias/patologia , Neoplasias/terapia , Osteoartrite/imunologia , Osteoartrite/patologia , Osteoartrite/terapia , Estabilidade Proteica , Estrutura Secundária de Proteína , Púrpura Trombocitopênica Trombótica/imunologia , Púrpura Trombocitopênica Trombótica/patologia , Púrpura Trombocitopênica Trombótica/terapia , Anticorpos de Domínio Único/uso terapêuticoRESUMO
The number of therapeutic antibodies in preclinical, clinical, or approved phases has been increasing exponentially, mostly due to their known successes. Development of antibody engineering methods has substantially hastened the development of therapeutic antibodies. A variety of protein engineering techniques can be applied to antibodies to improve their afinity and/or biophysical properties such as solubility and stability. Antibody fragments (where all or some parts of constant regions are eliminated while the essential antigen binding region is preserved) are more suitable for protein engineering techniques because there are many in vitro screening technologies available for antibody fragments but not full-length antibodies. Improvement of biophysical characteristics is important in the early development phase because most antibodies fail at the later stage of development and this leads to loss of resources and time. Here, we review directed evolution and rational design methods to improve antibody properties. Recent developments in rational design approaches and antibody display technologies, and especially phage display, which was recently awarded the 2018 Nobel Prize, are discussed to be used in antibody research and development.
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PURPOSE: Beverages may affect the translucency of esthetic dental restorative materials. The aim of the present study was to investigate the effects of coffee and red wine on the translucency of a PICN material with two translucency levels, and finished with different methods. MATERIALS AND METHODS: 2M2 high translucent and translucent VITA Enamic hybrid ceramic blocks were investigated. Rectangular specimens with the dimensions of 12 mm × 14 mm × 2 mm were prepared. The specimens were finished and polished with different methods as suggested by the manufacturer. The translucency parameters of the specimens were evaluated before and after 24 hours, 7 days, and 28 days immersion in distilled water, coffee and red wine. Translucency parameters were measured using a portable spectrophotometer. RESULTS: At the end of 28 days, there was no statistically significant difference between the groups of specimens kept in coffee (P>.05). In the red wine groups, there was a statistically significant difference between the control group and all other groups (P<.05) at the end of 28 days. CONCLUSION: The translucency of hybrid ceramic for a restoration may not be important regarding the effects of coffee on translucency change because the specimens with different translucencies and finishing methods that were immersed to coffee had similar translucency parameters at the end of 28 days. The translucency of hybrid ceramic may be important in the case of red wine, however, since the results showed that highly translucent specimens exposed to red wine demonstrated better translucency parameters than specimens made from translucent blocks at the end of 28 days.
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PURPOSE: Polymer infiltrated ceramic network (PICN) materials, also called hybrid ceramics, are new materials in dental market. The manufacturer of the PICN material VITA Enamic suggests 3 different finishing procedures for this new material. In the present study, surface roughness and color differences caused from different finishing procedures of VITA Enamic were investigated. MATERIALS AND METHODS: 120 specimens were prepared in dimensions 2 × 10 × 12 mm from VITA Enamic hybrid ceramic blocks with 'high translucency' and 'translucency 2M2' shades. The specimens were divided into 8 groups. For each group, different finishing procedures suggested by the manufacturer were performed. Surface roughness values were determined by a tactile portable profilometer. Color changes were evaluated using a clinical spectrophotometer. The data were analyzed using one-way ANOVA and Tukey's post-hoc comparison. The significance level was set at α=0.05. RESULTS: The roughest surfaces were observed in Glaze Groups. Their surface roughness values were similar to that of the control group. Clinical Kit and Technical Kit groups did not show a statistically significant difference regarding surface roughness (P>.05). The largest color difference regarding ΔE00 was observed in Clinical Kit finishing groups. There were also statistically significant color changes between the groups (P<.05). However, all the groups showed clinically acceptable color change (ΔE00<2.25) except Clinical Kit Groups (ΔE00>2.25). CONCLUSION: Within the limitations of the present study, it may be suggested that finishing the VITA Enamic restorations by Technical Kit instead of Glaze and Clinical Kit gives better clinical performance in regard to surface roughness and shade matching.