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RNA structure formation in vivo happens co-transcriptionally while the transcript is being made. The corresponding co-transcriptional folding pathway typically involves transient RNA structure features that are not part of the final, functional RNA structure. These transient features can play important functional roles of their own and also influence the formation of the final RNA structure in vivo. We here present CoBold, a computational method for identifying different functional classes of transient RNA structure features that can either aid or hinder the formation of a known reference RNA structure. Our method takes as input either a single RNA or a corresponding multiple-sequence alignment as well as a known reference RNA secondary structure and identifies different classes of transient RNA structure features that could aid or prevent the formation of the given RNA structure. We make CoBold available via a web-server which includes dedicated data visualisation.
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RNA/química , Análise de Sequência de RNA/métodos , Regiões 5' não Traduzidas , Biologia Computacional/métodos , Evolução Molecular , Conformação de Ácido Nucleico , Dobramento de RNA , RNA Catalítico/química , Riboswitch , Alinhamento de Sequência , Software , Transcrição GênicaRESUMO
Interactions between biological entities are key to understanding their potential functional roles. Three fields of research have recently made particular progress: the investigation of transRNA-RNA and RNA-DNA transcriptome interactions and of trans DNA-DNA genome interactions. We now have both experimental and computational methods for examining these interactions in vivo and on a transcriptome- and genome-wide scale, respectively. Often, key insights can be gained by visually inspecting figures that manage to combine different sources of evidence and quantitative information. We here present R-chie, a web server and R package for visualizing cis and transRNA-RNA, RNA-DNA and DNA-DNA interactions. For this, we have completely revised and significantly extended an earlier version of R-chie (1) which was initially introduced for visualizing RNA secondary structure features. The new R-chie offers a range of unique features for visualizing cis and transRNA-RNA, RNA-DNA and DNA-DNA interactions. Particularly note-worthy features include the ability to incorporate evolutionary information, e.g. multiple-sequence alignments, to compare two alternative sets of information and to incorporate detailed, quantitative information. R-chie is readily available via a web server as well as a corresponding R package called R4RNA which can be used to run the software locally.
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DNA/química , RNA/química , Software , Humanos , Internet , Conformação de Ácido Nucleico , Alinhamento de Sequência , TranscriptomaRESUMO
Several high-speed wireless systems use Orthogonal Frequency Division Multiplexing (OFDM) due to its advantages. 5G has adopted OFDM and is expected to be considered beyond 5G (B5G). Meanwhile, OFDM has a high Peak-to-Average Power Ratio (PAPR) problem. Hybridization between two PAPR reduction techniques gains the two techniques' advantages. Hybrid precoding-companding techniques are attractive as they require small computational complexity to achieve high PAPR reduction gain. Many precoding-companding techniques were introduced to increasing the PAPR reduction gain. However, reducing Bit Error Rate (BER) and out-of-band (OOB) radiation are more significant than increasing PAPR reduction gain. This paper proposes a new precoding-companding technique to better reduce the BER and OOB radiation than previous precoding-companding techniques. Results showed that the proposed technique outperforms all previous precoding-companding techniques in BER enhancement and OOB radiation reduction. The proposed technique reduces the Error Vector Magnitude (EVM) by 15 dB compared with 10 dB for the best previous technique. Additionally, the proposed technique increases high power amplifier efficiency (HPA) by 11.4%, while the best previous technique increased HPA efficiency by 9.8%. Moreover, our proposal achieves PAPR reduction gain better than the most known powerful PAPR reduction technique with a 99% reduction in required computational complexity.
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The advent of Next-Generation Sequencing (NGS) technologies has opened new perspectives in deciphering the genetic mechanisms underlying complex diseases. Nowadays, the amount of genomic data is massive and substantial efforts and new tools are required to unveil the information hidden in the data. The Genomic Data Commons (GDC) Data Portal is a platform that contains different genomic studies including the ones from The Cancer Genome Atlas (TCGA) and the Therapeutically Applicable Research to Generate Effective Treatments (TARGET) initiatives, accounting for more than 40 tumor types originating from nearly 30000 patients. Such platforms, although very attractive, must make sure the stored data are easily accessible and adequately harmonized. Moreover, they have the primary focus on the data storage in a unique place, and they do not provide a comprehensive toolkit for analyses and interpretation of the data. To fulfill this urgent need, comprehensive but easily accessible computational methods for integrative analyses of genomic data that do not renounce a robust statistical and theoretical framework are required. In this context, the R/Bioconductor package TCGAbiolinks was developed, offering a variety of bioinformatics functionalities. Here we introduce new features and enhancements of TCGAbiolinks in terms of i) more accurate and flexible pipelines for differential expression analyses, ii) different methods for tumor purity estimation and filtering, iii) integration of normal samples from other platforms iv) support for other genomics datasets, exemplified here by the TARGET data. Evidence has shown that accounting for tumor purity is essential in the study of tumorigenesis, as these factors promote confounding behavior regarding differential expression analysis. With this in mind, we implemented these filtering procedures in TCGAbiolinks. Moreover, a limitation of some of the TCGA datasets is the unavailability or paucity of corresponding normal samples. We thus integrated into TCGAbiolinks the possibility to use normal samples from the Genotype-Tissue Expression (GTEx) project, which is another large-scale repository cataloging gene expression from healthy individuals. The new functionalities are available in the TCGAbiolinks version 2.8 and higher released in Bioconductor version 3.7.
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Sequenciamento de Nucleotídeos em Larga Escala , Neoplasias/genética , Carcinogênese , Conjuntos de Dados como Assunto , Genoma Humano , HumanosRESUMO
PURPOSE: The aim of the present study was to evaluate the accuracy of 3-dimensionally (3D) printed patient-specific guides (PSGs) to direct the passage of inlet and outlet needles into the superior joint spaces of the temporomandibular joint (TMJ) in preparation for arthrocentesis. PATIENTS AND METHODS: The present study included 10 patients with 14 TMJs with anterior disc displacement with reduction. A 3D PSG was designed for each patient to lead the inlet and outlet needles into the superior joint space of the TMJ. The PSGs were implemented, and their accuracy for guiding the needles into the superior joint space was assessed. RESULTS: Both arthroscopic verification and clinical evaluation revealed that direct access to all the predetermined anatomic locations inside the TMJs had been obtained, except for 1 case, during which the patient had failed to maintain the maximum mouth opening during computed tomography scanning. CONCLUSIONS: The virtual computer-initiated PSGs were beneficial for directing the passage of the needles into the superior joint space.
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Luxações Articulares , Transtornos da Articulação Temporomandibular , Artrocentese , Humanos , Amplitude de Movimento Articular , Articulação TemporomandibularRESUMO
BACKGROUND: Genomic initiatives such as The Cancer Genome Atlas (TCGA) contain data from -omics profiling of thousands of tumor samples, which may be used to decipher cancer signaling, and related alterations. Managing and analyzing data from large-scale projects, such as TCGA, is a demanding task. It is difficult to dissect the high complexity hidden in genomic data and to account for inter-tumor heterogeneity adequately. METHODS: In this study, we used a robust statistical framework along with the integration of diverse bioinformatic tools to analyze next-generation sequencing data from more than 1000 patients from two different lung cancer subtypes, i.e., the lung adenocarcinoma (LUAD) and the squamous cell carcinoma (LUSC). RESULTS: We used the gene expression data to identify co-expression modules and differentially expressed genes to discriminate between LUAD and LUSC. We identified a group of genes which could act as specific oncogenes or tumor suppressor genes in one of the two lung cancer types, along with two dual role genes. Our results have been validated against other transcriptomics data of lung cancer patients. CONCLUSIONS: Our integrative approach allowed us to identify two key features: a substantial up-regulation of genes involved in O-glycosylation of mucins in LUAD, and a compromised immune response in LUSC. The immune-profile associated with LUSC might be linked to the activation of three oncogenic pathways, which promote the evasion of the antitumor immune response. Collectively, our results provide new future directions for the design of target therapies in lung cancer.
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Adenocarcinoma de Pulmão/genética , Carcinoma de Células Escamosas/genética , Neoplasias Pulmonares/genética , Glicoproteínas de Membrana/genética , Mucina-5B/genética , Mucinas/genética , Adenocarcinoma de Pulmão/imunologia , Carcinoma de Células Escamosas/imunologia , Estudos de Coortes , Bases de Dados de Ácidos Nucleicos , Regulação Neoplásica da Expressão Gênica , Glicosilação , Humanos , Interleucina-6/genética , Queratinas Tipo I/genética , Neoplasias Pulmonares/imunologia , Glicoproteínas de Membrana/metabolismo , Mucina-5B/metabolismo , Mucinas/metabolismo , Família Multigênica/genética , Modelos de Riscos Proporcionais , RNA-Seq , Transcriptoma , Microambiente Tumoral/imunologiaRESUMO
Placement of dental implants in the posterior mandibular alveolar ridges may become a challenging procedure because of limited bone height between the crest of the ridge and the inferior alveolar canal. The aim of this study was to introduce an innovative, less invasive, highly accurate, and easy surgical technique of inferior alveolar nerve lateralization in the posterior deficient mandible using a special customized 3-dimensional-printed surgical guide to enhance the bone height for implant placement. This case series study included 7 patients with unilateral edentulous mandibular alveolar ridges. Customized surgical guides were manufactured using fused deposition modeling technology to accurately place a rectangular window to uncover the canal and also for immediate placement of dental implants in all cases. The results of this limited study provided information on an innovative technique that decreased intraoperative time and demonstrated decreased risks for (1) inferior alveolar nerve injury and (2) postoperative nerve dysfunction.
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Implantação Dentária Endóssea , Implantes Dentários , Traumatismos do Nervo Trigêmeo , Humanos , Mandíbula , Nervo Mandibular , Traumatismos do Nervo Trigêmeo/prevenção & controleRESUMO
BACKGROUND: Using the sandwich osteotomy technique in the posterior mandible is delicate. This study aimed to assess the safety and the amount of bone gain using a full digital workflow versus the conventional procedure. PATIENTS AND METHODS: This split mouth study included 10 patients with bilateral vertically deficient posterior mandible. One side received conventional sandwich interpositional bone grafting (control group), while the other side received the same protocol using two patient-specific guides. The first guide (cutting guide) was used to place the osteotomies safely and accurately according to the predetermined dimensions and locations, and the second guide was used to fix the mobilized bony segment, leaving the desired gap to be filled with a particulate xenogenic bone graft. RESULTS: Full neurosensory recovery was documented at 2 months postoperative for all patients and bilaterally. After 4 months, there was a statistically significant difference in vertical bone gain between both groups (p = 0.001), measuring an average of 3.76 ± 0.72 mm in the study group and 2.69 ± 0.37 mm in the control group. No statistically significant difference was found between the planned vertical augmentation (3.85 ± 0.58 mm) and the obtained vertical bone gain (3.76 ± 0.72 mm) in the study group (p = 0.765) proving the accuracy of the guided procedure. CONCLUSION: Computer-guided sandwich interpositional grafting is predictable regarding the execution of the osteotomies and the accuracy of fixation of the transport segment.
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Mandíbula , Osteotomia , Humanos , Masculino , Feminino , Mandíbula/cirurgia , Adulto , Osteotomia/métodos , Pessoa de Meia-Idade , Fluxo de Trabalho , Transplante Ósseo/métodos , Aumento do Rebordo Alveolar/métodos , Cirurgia Assistida por Computador/métodosRESUMO
PURPOSE: To evaluate the effectiveness of using Densah burs for lifting the maxillary sinus membrane in cases with an oblique sinus floor with a residual bone height of 4-7 mm. METHODS: The study was conducted on 16 patients, comprising 9 males and 7 females, aged 25-60 years, split into two groups of 8 each: group I with a residual bone height of 4-5.5 mm below the sinus floor and group II with a residual bone height of 5.5-7 mm. Exclusion criteria included smokers, presence of systemic or metabolic conditions that contraindicate implant placement and a local sinus pathology. The study involved the use of Densah burs, using the osseodensification concept to elevate the sinus floor, along with simultaneous dental implant placement. The integrity of the sinus membrane was verified via clinical examination and a confirmatory cone beam computed tomography scan. RESULTS: The study revealed that out of the 16 cases, one case had a sinus membrane perforation, confirmed clinically at the time of the operation. The study achieved a mean lift of 4.42 mm and a mean final seating torque of 35.5 N/cm. At the 1-year follow-up, all cases showed clinical success, with no signs of sinus pathology or complications. CONCLUSIONS: In cases with oblique sinus floors and a residual bone height of 4-7 mm in moderately atrophic posterior maxilla, the osseodensification concept proved to be a safe and effective method for performing sinus lift procedures with simultaneous implantation.
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Implantes Dentários , Levantamento do Assoalho do Seio Maxilar , Masculino , Feminino , Humanos , Implantação Dentária Endóssea/métodos , Levantamento do Assoalho do Seio Maxilar/métodos , Estudos Prospectivos , Transplante Ósseo/métodosRESUMO
BACKGROUND: The sandwich osteotomy technique usually requires high surgical skills and prolonged intraoperative time and had some technical drawbacks with a subsequent deficient amount of vertical bone gain. The aim of this study was to evaluate the final vertical bone gain using sandwich osteotomy with simultaneous versus delayed implant placement in the anterior maxilla. MATERIAL AND METHODS: This study included 16 patients having multiple missing maxillary anterior teeth with a vertically deficient alveolar ridge. Patients were randomly assigned into two equal groups. Both groups were treated using sandwich osteotomy with interpositional particulate bovine bone graft. In the study group (8 patients, 17 implants), the transport mobilized bone segment was fixed in position using simultaneous implant placement. Whereas in the control group (8 patients, 18 implants), micro-plates and screws were used, followed by a second-stage surgery for plates removal and delayed implant placement. Radiographic assessment included 4 months postoperative mean of vertical gain in alveolar ridge height, taken from cross-sectional cuts of cone beam CT. RESULTS: The mean vertical bone gain in the study group was 4.04 ± 0.59 mm compared to 3.86 ± 0.52 mm in the control group with no statistically significant difference (p = 0.518). The mean value of bone gain percentage in the study group was 33.02% compared to 31.75% in the control group, with no statistically significant difference (p = 0.656). CONCLUSION: The sandwich osteotomy technique with simultaneous implant placement is a reliable method for vertical ridge augmentation that eliminates the need for a secondary surgery.
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Aumento do Rebordo Alveolar , Implantes Dentários , Humanos , Animais , Bovinos , Maxila/diagnóstico por imagem , Maxila/cirurgia , Aumento do Rebordo Alveolar/métodos , Estudos Transversais , Transplante Ósseo/métodos , Osteotomia/métodos , Processo Alveolar/diagnóstico por imagem , Processo Alveolar/cirurgia , Implantação Dentária Endóssea/métodosRESUMO
PURPOSE: The present study compared the absorbable gelatin sponge as a space-filling material versus anorganic bone bovine mineral (ABBM) in maxillary sinus augmentation with simultaneous endosseous dental implant placement. METHODS: Eighteen maxillary sinus floor elevation cases were randomly allocated into two groups. The first group received ABBM, while the second group received an absorbable gelatin sponge as a space-filling material. For both groups, CBCT scans were obtained immediately postoperatively and six months later to calculate the difference in sinus floor bone gain. Osstell readings were recorded both at the time of implant placement and implant exposure with a total of twenty-three dental implant placements in relation to the eighteen elevated sinus floors. RESULTS: The mean radiographic sinus floor gain in the ABBM group was 10.2 mm (± 2.5), while in the absorbable gelatin sponge group was 5.4 mm (± 2.0), with a mean difference of 4.8, which was statistically significant (p < 0.001). The mean implant stability for the ABBM was 77.3 (± 4.9), while in the absorbable gelatin sponge group was 74.2 (± 3.0), with a mean difference of 3.1, which was statistically insignificant (p = 0.1610). CONCLUSION: The ABBM showed superior results regarding the amount of radiographic sinus floor bone gain. However, the implant stability was invariable between both groups.
Assuntos
Substitutos Ósseos , Implantes Dentários , Levantamento do Assoalho do Seio Maxilar , Humanos , Bovinos , Animais , Levantamento do Assoalho do Seio Maxilar/métodos , Seio Maxilar/diagnóstico por imagem , Seio Maxilar/cirurgia , Esponja de Gelatina Absorvível , Implantação Dentária Endóssea/métodos , Transplante Ósseo/métodos , MineraisRESUMO
PURPOSE: To assess the radiographic and histomorphometric outcomes of horizontally augmented maxillary alveolar ridges using solid nonperforated customized titanium barriers. MATERIALS AND METHODS: This case series study included patients who received guided bone regeneration treatment in the anterior maxillary esthetic zone (eight patients, 18 dental implants) using patient-specific solid titanium barriers loaded with a mix of autogenous and xenogenic particulate bone grafts. A radiographic comparison between three time periods (immediately postoperative, 4 months, and 10 months) included software-aided calibration of the linear changes in the horizontal dimensions on CBCT cross-sectional cuts after being standardized. Bone core specimens were retrieved for histomorphometric analysis by the time of implant insertion. RESULTS: Wound healing was uneventful, except for two patients who showed soft tissue breakdown that did not affect the outcome. There was a statistically significant difference between the mean horizontal bone change at the different time intervals (P < .001), with a 79.6% ± 29.2% mean area of newly formed bone. CONCLUSION: GBR using customized solid titanium barriers appears to be efficient and promising concerning the final horizontal bone gain and the quality of the augmented sites.
Assuntos
Aumento do Rebordo Alveolar , Implantes Dentários , Humanos , Implantação Dentária Endóssea/métodos , Titânio , Aumento do Rebordo Alveolar/métodos , Estudos Transversais , Estética Dentária , Regeneração Óssea , Transplante Ósseo/métodosRESUMO
Vaccination remains the leading control method against infectious bronchitis (IB) in poultry despite the frequently observed IB outbreaks in vaccinated flocks. Here, two vaccination regimes were evaluated against challenge with the Massachusetts (Mass) infectious bronchitis virus (IBV) strain that was linked to egg production defects in Western Canada. One vaccination strategy included live attenuated IB vaccines only, and the other used both inactivated and live attenuated IB vaccines. The two immunization programs involved priming with a monovalent live attenuated IB vaccine (Mass serotype) at day-old, followed by intervals of bivalent live attenuated IB vaccines containing the Mass and Connecticut (Conn) serotypes given to the pullets at 2-, 5-, 9-, and 14-week-old. Inactivated IB vaccine (Mass serotype) was administrated to only one group of the vaccinated birds at 14-week-old. At the peak of lay, the hens were challenged with the Mass IBV isolate (15AB-01) via the oculo-nasal route. The efficacy of the vaccines was assessed following the challenge by observing clinical signs, egg production, egg quality parameters, seroconversion, and systemic T-cell subsets (CD4+ and CD8+ cells). Moreover, the viral genome loads in the oropharyngeal (OP) and cloacal (CL) swabs were quantified at predetermined time points. At 14 days post-infection (dpi), all the hens were euthanized, and different tissues were collected for genome load quantification and histopathological examination. Post-challenge, both vaccination regimes showed protection against clinical signs and exhibited significantly higher albumen parameters, higher anti-IBV serum antibodies, and significantly lower levels of IBV genome loads in OP swabs (at 3 and 7 dpi) and trachea and cecal tonsils compared to the mock-vaccinated challenged group. However, only the birds that received live attenuated plus inactivated IB vaccines had significantly lower IBV genome loads in CL swabs at 7 dpi, as well as decreased histopathological lesion scores and IBV genome loads in magnum compared to the mock-vaccinated challenged group, suggesting a slightly better performance for using live attenuated and inactivated IB vaccines in combination. Overall, the present findings show no significant difference in protection between the two vaccination regimes against the Mass IBV challenge in laying hens.
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BACKGROUND: This study aims to prospect the soft and hard tissue changes after augmentation of two different local mandibular contour defects using polyetheretherketone (PEEK) patient-specific onlay implants. METHODS: Six patients with disfiguring local mandibular deformities were included in this study (five males and one female) and received seven PEEK patient-specific implants (PSI), virtually designed and surgically settled to augment seven mandibular defects, three deficient chins, and four mandibular angels. The analysis of the soft and hard tissue changes utilized the superimposition of the preoperative and the 6-month postoperative sagittal and coronal CT views, after standardizing the radiographic interpretation. RESULTS: The soft tissue gain for the chin was 6.8 mm ± 0.98 with a 45.8% increase versus 4.42 mm ± 0.41 with a 22.9% increase for the angle. The difference in the soft tissue gain between the two groups was statistically significant (P = 0.0001). Comparing the soft tissue gain to the planned implant thickness, the percentage of the soft tissue gain for the chin recorded 109.2% versus 65.57% for the angle. The difference between the two groups was also statistically significant (P < 0.0001). CONCLUSION: PEEK patient-specific onlay implants represented an efficient and straightforward modality to augment local mandibular contour deformities with favorable esthetic outcomes; the total soft tissue profile gain of the chin region markedly exceeded that of the mandibular angle.
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Implantes Dentários , Benzofenonas , Estética Dentária , Feminino , Humanos , Cetonas , Masculino , Polietilenoglicóis , PolímerosRESUMO
INTRODUCTION: Gastro-esophageal reflux disease (GERD) is a common gastrointestinal disorder that occurs when backflow of the gastric contents into the esophagus results in troublesome symptoms. Though GERD has been extensively studied in Western populations, literature on the management of GERD in patients in Africa and Middle East (AME) is scarce. AREAS COVERED: In this review, we provide an overview of the management of mild-to-moderate GERD in AME. Here we focus on the efficacy and safety of currently available treatments for GERD to help physicians and community pharmacists appropriately manage patients with mild-to-moderate GERD in the primary healthcare setting, detailing specific situations and patient scenarios that are relevant to the region, including management of GERD during Ramadan and post-bariatric surgery. EXPERT OPINION: Under-appreciation of the burden of GERD in the region has resulted in a lack of consensus on management. Barriers that currently prevent the adoption of treatment guidelines in the primary healthcare setting may include lack of availability of local guidelines and referral systems, a paucity of region-specific research, and dogmatic adherence to traditional practice. By increasing awareness, strengthening knowledge, and by more effective utilization of resources, physicians and pharmacists could optimize GERD management strategies to better support patients.
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Gastroenterologistas , Refluxo Gastroesofágico , África/epidemiologia , Refluxo Gastroesofágico/diagnóstico , Refluxo Gastroesofágico/terapia , Humanos , Oriente MédioRESUMO
Genetic diversity and evolution of infectious bronchitis virus (IBV) are mainly impacted by mutations in the spike 1 (S1) gene. This study focused on whole genome sequencing of an IBV isolate (IBV/Ck/Can/2558004), which represents strains highly prevalent in Canadian commercial poultry, especially concerning features related to its S1 gene and protein sequences. Based on the phylogeny of the S1 gene, IBV/Ck/Can/2558004 belongs to the GI-17 lineage. According to S1 gene and protein pairwise alignment, IBV/Ck/Can/2558004 had 99.44-99.63% and 98.88-99.25% nucleotide (nt) and deduced amino acid (aa) identities, respectively, with five Canadian Delmarva (DMV/1639) IBVs isolated in 2019, and it also shared 96.63-97.69% and 94.78-97.20% nt and aa similarities with US DMV/1639 IBVs isolated in 2011 and 2019, respectively. Further homology analysis of aa sequences showed the existence of some aa substitutions in the hypervariable regions (HVRs) of the S1 protein of IBV/Ck/Can/2558004 compared to US DMV/1639 isolates; most of these variant aa residues have been subjected to positive selection pressure. Predictive analysis of potential N-glycosylation and phosphorylation motifs showed either loss or acquisition in the S1 glycoprotein of IBV/Ck/Can/2558004 compared to S1 of US DMV/1639 IBV. Furthermore, bioinformatic analysis showed some of the aa changes within the S1 protein of IBV/Ck/Can/2558004 have been predicted to impact the function and structure of the S1 protein, potentially leading to a lower binding affinity of the S1 protein to its relevant ligand (sialic acid). In conclusion, these findings revealed that the DMV/1639 IBV isolates are under continuous evolution among Canadian poultry.
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Infecções por Coronavirus , Vírus da Bronquite Infecciosa , Doenças das Aves Domésticas , Aminoácidos/genética , Animais , Canadá , Galinhas , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/veterinária , Genótipo , Glicoproteínas/genética , Vírus da Bronquite Infecciosa/genética , Ligantes , Ácido N-Acetilneuramínico , Nucleotídeos , Aves DomésticasRESUMO
BACKGROUND: Ridge splitting technique is considered one of the successful horizontal bone augmentation procedures especially for the maxillary bone, the aim of this study was to compare marginal bone loss using a novel ridge splitting protocol versus the conventional technique. MATERIAL & METHODS: This was a randomized clinical trial including 20 patients who were randomly assigned to ridge splitting with simultaneous implant placement at the anterior maxillary aesthetic zone (10 patients, 29 dental implant) using patient specific guides (PSGs) or conventional technique (10 patients, 29 dental implant). In the control group free hand ridge splitting was done, while in the study group all the splitting and drilling procedures were done through specific slits and sleeves at the patient specific guides. Radiographic Assessment included measurements of linear changes in the vertical dimensions of the labial plate of bone on cross sectional cuts of computed tomography (CBCT) using mimics software. RESULTS: Wound healing was uneventful for all the patients except one patient in the control group that showed bad split and another showed buccal fenestration. The study group showed lower bone loss (1.38 ± 0.61 mm) compared to the control group (2.42 ± 0.63 mm), with statistical significance difference (P value = 0.001). The loss percentage also was higher in the study group (10.99 ± 4.76%) compared to the control group (19.12 ± 4.53%), and there was statistical significance difference between the two groups (P value = 0.001). CONCLUSION: Ridge splitting using PSGs appear to be efficient and promising than the free hand technique.
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Aumento do Rebordo Alveolar , Implantes Dentários , Transplante Ósseo , Computadores , Estudos Transversais , Implantação Dentária Endóssea , Estética Dentária , Humanos , Maxila/diagnóstico por imagem , Maxila/cirurgiaRESUMO
BACKGROUND: Sandwich osteotomy technique (Inlay bone grafting) is considered as a highly reliable procedure for vertical bone augmentation in the maxillary anterior esthetic zone. The aim of this study was to compare vertical bone gain and palatal tipping using computer-guided inlay technique versus the conventional technique. MATERIAL AND METHODS: This was a randomized clinical trial including 12 patients who were randomly divided into two groups: sandwich osteotomy with simultaneous implant placement at the anterior maxillary esthetic zone (six patients) using patient-specific guides (PSGs) in the study group versus conventional technique (six patients). In the control group, free-hand sandwich osteotomy was done, while in the study group all the procedures were performed with two sequential PSGs with cutting slits, guiding holes, and implant sleeves. Radiographic assessment included measurements of linear changes in the vertical dimensions of the labial plate of bone and palatal tipping on cross-sectional cuts of cone-beam computed tomography using special software. RESULTS: All the procedures were uneventful except one case of the study group showed a cracked bony segment that did not affect the final outcome. Radiographic results showed comparable bone gain in both groups with no statistical significance difference (study group 4.4 mm, control group 3.9 mm). To the contrary, the computer-guided approach significantly reduced the palatal tipping to 0.4 mm compared to 2.1 mm in the conventional group, and there was a statistically significant difference between the two groups (p-value <0.001). CONCLUSION: Sandwich osteotomy using PSGs appears to be efficient and showed promising results regarding improving the palatal tipping compared to the free-hand technique.
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Aumento do Rebordo Alveolar , Implantes Dentários , Transplante Ósseo , Computadores , Estudos Transversais , Implantação Dentária Endóssea , Estética Dentária , Humanos , Maxila/diagnóstico por imagem , Maxila/cirurgia , Osteotomia , Projetos PilotoRESUMO
PURPOSE: This study aims to compare the quality of free autogenous bone grafts harvested from two different mandibular donor sites, used as onlay shells to augment horizontally and vertically deficient anterior maxillary alveolar ridges. METHODS: Fourteen patients with edentulous and atrophic anterior maxillae are randomly allocated into two groups. Seven symphyseal chin (group I) and seven retromolar (group II) mandibular bone grafts were harvested and fashioned to construct buccal and palatal frameworks, fixed in place with mini-screws, followed by compacting the inter-positional gaps with an equal particulate mix of xenograft and autogenous cancellous particulates. Six months later, 42 core biopsies, three from each patient, 21 for each study group, were retrieved before the implants' insertion and subjected to histomorphometric bone area percent analysis. RESULTS: The bone area percent of the newly formed bone augmented with the chin shells was 52.53 ± 1.68% versus 47.97 ± 1.83% for the retromolar grafts. The mean area percent difference between both groups was statistically significant (p = 0.0004). CONCLUSION: A higher bone quality and more volumetric stability were associated with the symphyseal cortical shells. CLINICAL TRIAL REGISTRATION: The study was registered on www.clinicaltrials.gov (#: NCT03607006) in July 2018 by Ola Alaa El Morsy.