Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 52
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Virus Genes ; 60(4): 402-411, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38717669

RESUMO

A wide diversity of mycoviruses has been reported from Botrytis species, some with the potential to suppress the pathogenic abilities of this fungus. Considering their importance, this study was devised to find potential hypovirulence-associated mycoviruses found in Botrytis cinerea strains isolated from Pakistani strawberry fields. Here we report the complete genome characterization of two fusariviruses co-infecting a single isolate of phytopathogenic fungus B. cinerea (Kst14a). The viral genomes were sequenced by deep sequencing using total RNA fractions of the Kst14a isolate. The identified viruses were tentatively named Botrytis cinerea fusarivirus 9 (BcFV9) and Botrytis cinerea fusarivirus 3a (BcFV3a). Both viruses had a single-segmented (ssRNA) genome having a size of 6424 and 8370 nucleotides encoding two discontinuous open reading frames (ORFs). ORF-1 of both mycoviruses encodes for a polyprotein having a conserved domain of RNA-dependent RNA polymerase (RdRP) and a helicase domain (Hel) which function in RNA replication, while ORF2 encodes a hypothetical protein with an unknown function, respectively. Phylogenetic analysis indicated that BcFV9 made a clade with the genus Alphafusarivirus and BcFV3a fall in the genus Betafusarivirus in the family Fusariviridae. To our knowledge, this is the first report of two fusariviruses identified in isolates of B. cinerea from Pakistan. Both mycoviruses successfully transfected to a compatible strain of B. cinerea (Mst11). A comparison of virus-free (VF) and virus-infected (VI) isogenic lines showed the presence of these viruses was causing hypovirulence in infected strains. Virus-infected strains also had a small lesion size while testing the pathogenicity via apple assay.


Assuntos
Botrytis , Micovírus , Genoma Viral , Fases de Leitura Aberta , Filogenia , Doenças das Plantas , Botrytis/virologia , Botrytis/genética , Micovírus/genética , Micovírus/isolamento & purificação , Micovírus/classificação , Doenças das Plantas/microbiologia , RNA Viral/genética , Fragaria/microbiologia , Fragaria/virologia , Paquistão , Proteínas Virais/genética , Sequenciamento de Nucleotídeos em Larga Escala
2.
Sensors (Basel) ; 24(13)2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-39001190

RESUMO

LoRa enables long-range communication for Internet of Things (IoT) devices, especially those with limited resources and low power requirements. Consequently, LoRa has emerged as a popular choice for numerous IoT applications. However, the security of LoRa devices is one of the major concerns that requires attention. Existing device identification mechanisms use cryptography which has two major issues: (1) cryptography is hard on the device resources and (2) physical attacks might prevent them from being effective. Deep learning-based radio frequency fingerprinting identification (RFFI) is emerging as a key candidate for device identification using hardware-intrinsic features. In this paper, we present a comprehensive survey of the state of the art in the area of deep learning-based radio frequency fingerprinting identification for LoRa devices. We discuss various categories of radio frequency fingerprinting techniques along with hardware imperfections that can be exploited to identify an emitter. Furthermore, we describe different deep learning algorithms implemented for the task of LoRa device classification and summarize the main approaches and results. We discuss several representations of the LoRa signal used as input to deep learning models. Additionally, we provide a thorough review of all the LoRa RF signal datasets used in the literature and summarize details about the hardware used, the type of signals collected, the features provided, availability, and size. Finally, we conclude this paper by discussing the existing challenges in deep learning-based LoRa device identification and also envisage future research directions and opportunities.

3.
J Pak Med Assoc ; 73(Suppl 1)(2): S9-S13, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36788385

RESUMO

Objectives: To assess knowledge and awareness of dental healthcare professionals on dental stem cells. METHODS: A questionnaire survey-based study was conducted using Google forms on a sample of 69 dental healthcare professionals (DHCP) from September - October 2022, after obtaining ethical approval. A validated questionnaire was used to assess the knowledge and awareness of dental healthcare professionals on stem cells, which was then divided into three sections. The section A was about demographic statistics, section B assessed knowledge and awareness regarding dental stem cells and section C consisted of 5 score VAS scale to assess the acceptability of future research and increase implication of dental stem cells (DSC) among DHCP. The frequency of each question was reported in percentages. To assess the difference of knowledge and awareness of DSC among different specialties of DHCP, one-way ANOVA test was applied and incase of significant results pairwise comparison was performed by post-hoc Tukey test. RESULTS: Mean scores of knowledge and awareness of DSC among female DHCP were 54.26 ± 11.73 and males were 53.50 ±8.19. There was a statistically significant difference of knowledge (p= 0.02) among different dental healthcare professionals. On pairwise comparison by post-hoc Tukey HSD we found statistically significant difference (p = 0.03) of knowledge and awareness of dental stem cells among general dentists and operative dentistry specialists. CONCLUSIONS: We found poor knowledge and awareness of dental healthcare professionals regarding dental stem cells. However, operative and endodontic specialty had more awareness on dental stem cells as compared to any other specialty. There was positive approach for further future researches on stem cells.


Assuntos
Odontólogos , Conhecimentos, Atitudes e Prática em Saúde , Masculino , Humanos , Feminino , Estudos Transversais , Inquéritos e Questionários , Células-Tronco
4.
J Pak Med Assoc ; 73(Suppl 1)(2): S62-S68, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36788393

RESUMO

Oral mesenchymal stem cell populations in humans have been discovered in close vicinity to oral mucosal tissues and both primary (deciduous) and secondary (permanent) teeth. All these different kinds of stem cells have the ability to divide and replenish themselves, however they vary in their gene expression profiles and their capacity to give rise to distinct cell lineages. They all have multipotentiality i.e. chondrogenic, osteogenic, adipogenic, and neurogenic. Due to their relative accessibility, these cell types may form a source of stem cells with substantial potential for application in tissue regeneration. In this review, discoveries outlining stem cell potential are discussed on various aspects as, are their various applications in orthodontics i.e. orthodontic tooth movement, fixing external root resorption, correcting craniofacial anomalies, accelerating craniofacial distraction osteogenesis, recreating the TMJ, and ensuring a stable maxillary expansion.


Assuntos
Células-Tronco Mesenquimais , Ortodontia , Humanos , Dente Decíduo , Diferenciação Celular , Células-Tronco
5.
J Pak Med Assoc ; 73(2): 346-351, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36800723

RESUMO

Lasers have been utilised in the field of dentistry for over 40 years, but their use has been limited in the field of orthodontics. The advent of lasers with accompanying computer interfaces has made them significantly user-friendly, adding to their appeal in the orthodontic profession. Knowledge regarding the laser device's capabilities and limitations is essential to optimise patient care and to make a satisfactory investment return. For the effective and successful integration of lasers in orthodontic practice, adequate training is required, limited not only to the orthodontist but the dental assistants and auxiliaries as well. Orthodontists may safely and readily execute gingivectomy, exposure of teeth, frenectomy, circumferential supracrestal fiberotomy, ankyloglossia release and uvulopalatoplasty. The current narrative review was planned to introduce the benefits and general principles of soft tissue lasers in the field of orthodontics and recent surgical research comparing different laser-assisted surgeries against conventional scalpel surgeries.


Assuntos
Assistência Odontológica , Lasers , Humanos , Conhecimento
6.
J Gen Virol ; 102(12)2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34850675

RESUMO

An extensive screening survey was conducted on Pakistani filamentous fungal isolates for the identification of viral infections. A total of 396 fungal samples were screened, of which 36 isolates were found double-stranded (ds) RNA positive with an overall frequency of 9% when analysed by a classical dsRNA isolation method. One of 36 dsRNA-positive strains, strain SP1 of a plant pathogenic fungus Fusarium mangiferae, was subjected to virome analysis. Next-generation sequencing and subsequent completion of the entire genome sequencing by a classical Sanger sequencing method showed the SP1 strain to be co-infected by 11 distinct viruses, at least seven of which should be described as new taxa at the species level according to the ICTV (International Committee on Taxonomy of Viruses) species demarcation criteria. The newly identified F. mangiferae viruses (FmVs) include two partitivirids, one betapartitivirus (FmPV1) and one gammapartitivirus (FmPV2); six mitovirids, three unuamitovirus (FmMV2, FmMV4, FmMV6), one duamitovirus (FmMV5), and two unclassified mitovirids (FmMV1, FmMV3); and three botourmiavirids, two magoulivirus (FmBOV1, FmBOV3) and one scleroulivirus (FmBOV2). The number of coinfecting viruses is among the largest ones of fungal coinfections. Their molecular features are thoroughly described here. This represents the first large virus survey in the Indian sub-continent.


Assuntos
Micovírus/genética , Fusarium/virologia , Micovírus/classificação , Micovírus/ultraestrutura , Fusarium/isolamento & purificação , Genoma Viral/genética , Paquistão , Filogenia , Doenças das Plantas/microbiologia , Plantas/microbiologia , Vírus de RNA/classificação , Vírus de RNA/genética , Vírus de RNA/ultraestrutura , RNA Viral/genética , Proteínas Virais/genética , Viroma/genética
7.
J Pak Med Assoc ; 71(1(A)): 12-15, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33484510

RESUMO

OBJECTIVES: To determine the effectiveness of Mulligan mobilisation versus Cyriax approach in the management of patients with subacute lateral epicondylitis. METHODS: The clinical trial was conducted at the District Headquarter Hospital, Bahawalnagar, Pakistan, from September to December 2018, and comprised lateral epicondylitis patients having symptoms for >2 weeks. The diagnosis was confirmed on the basis of physical tests and musculoskeletal ultrasound. The subjects were randomly allocated to two equal groups A and B. Group A received deep transverse friction and Mill's manipulation according to Cyriax approach, while group B received Mulligan mobilisation with movement techniques. Patient-related tennis elbow evaluation index was used to collect data which was analysed using SPSS 20. RESULTS: Of the 60 patients, there were 30(50%) in each of the two groups. The overall mean age was 35.27±7.30 years, and 38(63.3%) participants were male. After 4 weeks of treatment sessions, both groups showed significant improvements (p<0.05) in pain and functional disability scores. Group A showed significantly more improvement (p<0.05) in pain subscale scores compared to group B, while group B showed significant improvement (p<0.05) in functional disability subscale scores compared to group A. There was no significant difference (p>0.05) between the groups on total the patient-related tennis elbow evaluation index score. CONCLUSIONS: Both Mulligan mobilisation with movement and Cyriax approach decreased pain and improved functional status in lateral epicondylitis patients.


Assuntos
Cotovelo de Tenista , Adulto , Feminino , Humanos , Masculino , Dor , Paquistão , Cotovelo de Tenista/diagnóstico por imagem , Cotovelo de Tenista/terapia , Resultado do Tratamento
8.
Gut ; 68(6): 1034-1043, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30658994

RESUMO

OBJECTIVE: Pancreatic ductal adenocarcinoma (PDA) has among the highest stromal fractions of any cancer and this has complicated attempts at expression-based molecular classification. The goal of this work is to profile purified samples of human PDA epithelium and stroma and examine their respective contributions to gene expression in bulk PDA samples. DESIGN: We used laser capture microdissection (LCM) and RNA sequencing to profile the expression of 60 matched pairs of human PDA malignant epithelium and stroma samples. We then used these data to train a computational model that allowed us to infer tissue composition and generate virtual compartment-specific expression profiles from bulk gene expression cohorts. RESULTS: Our analysis found significant variation in the tissue composition of pancreatic tumours from different public cohorts. Computational removal of stromal gene expression resulted in the reclassification of some tumours, reconciling functional differences between different cohorts. Furthermore, we established a novel classification signature from a total of 110 purified human PDA stroma samples, finding two groups that differ in the extracellular matrix-associated and immune-associated processes. Lastly, a systematic evaluation of cross-compartment subtypes spanning four patient cohorts indicated partial dependence between epithelial and stromal molecular subtypes. CONCLUSION: Our findings add clarity to the nature and number of molecular subtypes in PDA, expand our understanding of global transcriptional programmes in the stroma and harmonise the results of molecular subtyping efforts across independent cohorts.


Assuntos
Adenocarcinoma/patologia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Regulação Neoplásica da Expressão Gênica , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Adenocarcinoma/genética , Adenocarcinoma/cirurgia , Carcinoma Ductal Pancreático/cirurgia , Estudos de Casos e Controles , Simulação por Computador , Matriz Extracelular/patologia , Perfilação da Expressão Gênica , Humanos , Microdissecção , Neoplasias Pancreáticas/cirurgia , Sensibilidade e Especificidade
9.
Nucleic Acids Res ; 43(Database issue): D465-9, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25378330

RESUMO

For over 10 years, Binding MOAD (Mother of All Databases; http://www.BindingMOAD.org) has been one of the largest resources for high-quality protein-ligand complexes and associated binding affinity data. Binding MOAD has grown at the rate of 1994 complexes per year, on average. Currently, it contains 23,269 complexes and 8156 binding affinities. Our annual updates curate the data using a semi-automated literature search of the references cited within the PDB file, and we have recently upgraded our website and added new features and functionalities to better serve Binding MOAD users. In order to eliminate the legacy application server of the old platform and to accommodate new changes, the website has been completely rewritten in the LAMP (Linux, Apache, MySQL and PHP) environment. The improved user interface incorporates current third-party plugins for better visualization of protein and ligand molecules, and it provides features like sorting, filtering and filtered downloads. In addition to the field-based searching, Binding MOAD now can be searched by structural queries based on the ligand. In order to remove redundancy, Binding MOAD records are clustered in different families based on 90% sequence identity. The new Binding MOAD, with the upgraded platform, features and functionalities, is now equipped to better serve its users.


Assuntos
Bases de Dados de Proteínas , Proteínas/química , Internet , Ligantes , Ligação Proteica
11.
J Chem Inf Model ; 56(6): 1022-31, 2016 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-26419257

RESUMO

Community Structure-Activity Resource (CSAR) conducted a benchmark exercise to evaluate the current computational methods for protein design, ligand docking, and scoring/ranking. The exercise consisted of three phases. The first phase required the participants to identify and rank order which designed sequences were able to bind the small molecule digoxigenin. The second phase challenged the community to select a near-native pose of digoxigenin from a set of decoy poses for two of the designed proteins. The third phase investigated the ability of current methods to rank/score the binding affinity of 10 related steroids to one of the designed proteins (pKd = 4.1 to 6.7). We found that 11 of 13 groups were able to correctly select the sequence that bound digoxigenin, with most groups providing the correct three-dimensional structure for the backbone of the protein as well as all atoms of the active-site residues. Eleven of the 14 groups were able to select the appropriate pose from a set of plausible decoy poses. The ability to predict absolute binding affinities is still a difficult task, as 8 of 14 groups were able to correlate scores to affinity (Pearson-r > 0.7) of the designed protein for congeneric steroids and only 5 of 14 groups were able to correlate the ranks of the 10 related ligands (Spearman-ρ > 0.7).


Assuntos
Desenho de Fármacos , Simulação de Acoplamento Molecular , Proteínas/metabolismo , Sequência de Aminoácidos , Benchmarking , Digoxigenina/química , Digoxigenina/metabolismo , Ligantes , Ligação Proteica , Conformação Proteica , Proteínas/química , Relação Estrutura-Atividade
12.
J Chem Inf Model ; 56(6): 1063-77, 2016 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-27149958

RESUMO

The 2014 CSAR Benchmark Exercise was the last community-wide exercise that was conducted by the group at the University of Michigan, Ann Arbor. For this event, GlaxoSmithKline (GSK) donated unpublished crystal structures and affinity data from in-house projects. Three targets were used: tRNA (m1G37) methyltransferase (TrmD), Spleen Tyrosine Kinase (SYK), and Factor Xa (FXa). A particularly strong feature of the GSK data is its large size, which lends greater statistical significance to comparisons between different methods. In Phase 1 of the CSAR 2014 Exercise, participants were given several protein-ligand complexes and asked to identify the one near-native pose from among 200 decoys provided by CSAR. Though decoys were requested by the community, we found that they complicated our analysis. We could not discern whether poor predictions were failures of the chosen method or an incompatibility between the participant's method and the setup protocol we used. This problem is inherent to decoys, and we strongly advise against their use. In Phase 2, participants had to dock and rank/score a set of small molecules given only the SMILES strings of the ligands and a protein structure with a different ligand bound. Overall, docking was a success for most participants, much better in Phase 2 than in Phase 1. However, scoring was a greater challenge. No particular approach to docking and scoring had an edge, and successful methods included empirical, knowledge-based, machine-learning, shape-fitting, and even those with solvation and entropy terms. Several groups were successful in ranking TrmD and/or SYK, but ranking FXa ligands was intractable for all participants. Methods that were able to dock well across all submitted systems include MDock,1 Glide-XP,2 PLANTS,3 Wilma,4 Gold,5 SMINA,6 Glide-XP2/PELE,7 FlexX,8 and MedusaDock.9 In fact, the submission based on Glide-XP2/PELE7 cross-docked all ligands to many crystal structures, and it was particularly impressive to see success across an ensemble of protein structures for multiple targets. For scoring/ranking, submissions that showed statistically significant achievement include MDock1 using ITScore1,10 with a flexible-ligand term,11 SMINA6 using Autodock-Vina,12,13 FlexX8 using HYDE,14 and Glide-XP2 using XP DockScore2 with and without ROCS15 shape similarity.16 Of course, these results are for only three protein targets, and many more systems need to be investigated to truly identify which approaches are more successful than others. Furthermore, our exercise is not a competition.


Assuntos
Desenho de Fármacos , Simulação de Acoplamento Molecular , Proteínas/metabolismo , Benchmarking , Bases de Dados de Produtos Farmacêuticos , Fator Xa/química , Fator Xa/metabolismo , Ligantes , Conformação Proteica , Proteínas/química , Relação Estrutura-Atividade , Quinase Syk/química , Quinase Syk/metabolismo , tRNA Metiltransferases/química , tRNA Metiltransferases/metabolismo
13.
Cancer Cell Int ; 14(1): 133, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25663820

RESUMO

BACKGROUND: Despite the modern therapies available for treating glioblastoma multiforme (GBM), it is still a deadly disease. The development of new therapeutic strategies for the management of gliomas is therefore crucial. The present study is designed to analyze the therapeutic potentials of synthetic compound N-(2-hydroxyphenyl)acetamide (NA-2) in the treatment of GBM as a single agent or in combination with Temozolomide (TMZ) on glioblastoma cells. METHODS: MTT and TUNEL assays were used to detect the growth inhibitory effect and apoptotic activity of NA-2 alone and in combination with TMZ. Synergy was assessed using combination Index method. The expression of apoptosis related markers Bax, Bcl-2 and caspase-3 were assessed by RT-PCR, whereas, the active caspase-3 protein expression was determined using imunocytochemistry. RESULTS: Both NA-2 and TMZ inhibited the growth of U87 in a dose dependent manner. The combine administration of NA-2 (0.33 mM) and temozolomide (0.1 mM) significantly enhanced the cell growth inhibition and apoptosis. Furthermore RT-PCR and imunocytochemistry data revealed that cooperative apoptosis induction was associated with increased ratio of Bax to Bcl-2 and active Caspase-3 expression. CONCLUSION: Our findings support that NA-2 possesses strong apoptotic activity and the combined administration of NA-2 and TMZ may be therapeutically exploited for the management of GBM.

14.
Nucleic Acids Res ; 40(Web Server issue): W310-6, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22669906

RESUMO

The NMSim web server implements a three-step approach for multiscale modeling of protein conformational changes. First, the protein structure is coarse-grained using the FIRST software. Second, a rigid cluster normal-mode analysis provides low-frequency normal modes. Third, these modes are used to extend the recently introduced idea of constrained geometric simulations by biasing backbone motions of the protein, whereas side chain motions are biased toward favorable rotamer states (NMSim). The generated structures are iteratively corrected regarding steric clashes and stereochemical constraint violations. The approach allows performing three simulation types: unbiased exploration of conformational space; pathway generation by a targeted simulation; and radius of gyration-guided simulation. On a data set of proteins with experimentally observed conformational changes, the NMSim approach has been shown to be a computationally efficient alternative to molecular dynamics simulations for conformational sampling of proteins. The generated conformations and pathways of conformational transitions can serve as input to docking approaches or more sophisticated sampling techniques. The web server output is a trajectory of generated conformations, Jmol representations of the coarse-graining and a subset of the trajectory and data plots of structural analyses. The NMSim webserver, accessible at http://www.nmsim.de, is free and open to all users with no login requirement.


Assuntos
Modelos Moleculares , Conformação Proteica , Software , Adenilato Quinase/química , Simulação por Computador , Internet
15.
Proc Natl Acad Sci U S A ; 108(47): 18943-8, 2011 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-22080606

RESUMO

The dynamic nature of biomolecules leads to significant challenges when characterizing the structural properties associated with function. While X-ray crystallography and imaging techniques (such as cryo-electron microscopy) can reveal the structural details of stable molecular complexes, strategies must be developed to characterize configurations that exhibit only marginal stability (such as intermediates) or configurations that do not correspond to minima on the energy landscape (such as transition-state ensembles). Here, we present a methodology (MDfit) that utilizes molecular dynamics simulations to generate configurations of excited states that are consistent with available biophysical and biochemical measurements. To demonstrate the approach, we present a sequence of configurations that are suggested to be associated with transfer RNA (tRNA) movement through the ribosome (translocation). The models were constructed by combining information from X-ray crystallography, cryo-electron microscopy, and biochemical data. These models provide a structural framework for translocation that may be further investigated experimentally and theoretically to determine the precise energetic character of each configuration and the transition dynamics between them.


Assuntos
Modelos Moleculares , Simulação de Dinâmica Molecular , Conformação de Ácido Nucleico , RNA de Transferência/ultraestrutura , Ribossomos/ultraestrutura , Microscopia Crioeletrônica , Cristalografia por Raios X , Transporte de RNA/fisiologia
16.
Biochemistry ; 52(9): 1568-82, 2013 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-23363317

RESUMO

Soluble guanylyl/guanylate cyclase (sGC) converts GTP to cGMP after binding nitric oxide, leading to smooth muscle relaxation and vasodilation. Impaired sGC activity is common in cardiovascular disease, and sGC stimulatory compounds are vigorously sought. sGC is a 150 kDa heterodimeric protein with two H-NOX domains (one with heme, one without), two PAS domains, a coiled-coil domain, and two cyclase domains. Binding of NO to the sGC heme leads to proximal histidine release and stimulation of catalytic activity. To begin to understand how binding leads to activation, we examined truncated sGC proteins from Manduca sexta (tobacco hornworm) that bind NO, CO, and stimulatory compound YC-1 but lack the cyclase domains. We determined the overall shape of truncated M. sexta sGC using analytical ultracentrifugation and small-angle X-ray scattering (SAXS), revealing an elongated molecule with dimensions of 115 Å × 90 Å × 75 Å. Binding of NO, CO, or YC-1 had little effect on shape. Using chemical cross-linking and tandem mass spectrometry, we identified 20 intermolecular contacts, allowing us to fit homology models of the individual domains into the SAXS-derived molecular envelope. The resulting model displays a central parallel coiled-coil platform upon which the H-NOX and PAS domains are assembled. The ß1 H-NOX and α1 PAS domains are in contact and form the core signaling complex, while the α1 H-NOX domain can be removed without a significant effect on ligand binding or overall shape. Removal of 21 residues from the C-terminus yields a protein with dramatically increased proximal histidine release rates upon NO binding.


Assuntos
Reagentes de Ligações Cruzadas/química , Guanilato Ciclase/química , Guanilato Ciclase/metabolismo , Manduca/enzimologia , Receptores Citoplasmáticos e Nucleares/química , Receptores Citoplasmáticos e Nucleares/metabolismo , Animais , Monóxido de Carbono/metabolismo , Indazóis/metabolismo , Manduca/química , Manduca/metabolismo , Espectrometria de Massas , Modelos Moleculares , Óxido Nítrico/metabolismo , Ligação Proteica , Conformação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Espalhamento a Baixo Ângulo , Guanilil Ciclase Solúvel , Homologia Estrutural de Proteína , Ultracentrifugação , Difração de Raios X
17.
J Struct Biol ; 182(2): 67-77, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23416197

RESUMO

Cryo-electron microscopy (cryo-EM) can provide low-resolution density maps of large macromolecular assemblies. As the number of structures deposited in the Protein Data Bank by fitting a high-resolution structure into a low-resolution cryo-EM map is increasing, there is a need to revise the protocols and improve the measures for fitting. A recent study suggested using a combination of multiple automated flexible fitting approaches to improve the interpretation of cryo-EM data. The current work further explores the use of multiple approaches by validating this "consensus" fitting approach and deriving a local reliability measure. Here four different flexible fitting approaches are applied for fitting an initial structure into a simulated density map of known target structure from a dataset of proteins. It is found that the models produced from different approaches often have a consensus in conformation and are also near to the target structure, whereas cases not showing consensus are away from the target. A high correlation is also observed between the RMSF profiles calculated with respect to the average and the target structures, which indicates that the relation between consensus and accuracy can also be extended to a per-residue level. Therefore, the RMSF among the fitted models is proposed as a local reliability measure, which can be used to assess the reliability of the fit at specific regions. Hence, we encourage the community to use consensus flexible fitting with different methods to report on local reliability of the resulting models and improve the interpretation of cryo-EM data.


Assuntos
Microscopia Crioeletrônica/métodos , Processamento de Imagem Assistida por Computador/métodos , Substâncias Macromoleculares/ultraestrutura , Modelos Moleculares , Conformação Proteica , Bases de Dados de Proteínas , Simulação de Dinâmica Molecular
18.
J Chem Inf Model ; 53(8): 1842-52, 2013 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-23617227

RESUMO

A major goal in drug design is the improvement of computational methods for docking and scoring. The Community Structure Activity Resource (CSAR) has collected several data sets from industry and added in-house data sets that may be used for this purpose ( www.csardock.org). CSAR has currently obtained data from Abbott, GlaxoSmithKline, and Vertex and is working on obtaining data from several others. Combined with our in-house projects, we are providing a data set consisting of 6 protein targets, 647 compounds with biological affinities, and 82 crystal structures. Multiple congeneric series are available for several targets with a few representative crystal structures of each of the series. These series generally contain a few inactive compounds, usually not available in the literature, to provide an upper bound to the affinity range. The affinity ranges are typically 3-4 orders of magnitude per series. For our in-house projects, we have had compounds synthesized for biological testing. Affinities were measured by Thermofluor, Octet RED, and isothermal titration calorimetry for the most soluble. This allows the direct comparison of the biological affinities for those compounds, providing a measure of the variance in the experimental affinity. It appears that there can be considerable variance in the absolute value of the affinity, making the prediction of the absolute value ill-defined. However, the relative rankings within the methods are much better, and this fits with the observation that predicting relative ranking is a more tractable problem computationally. For those in-house compounds, we also have measured the following physical properties: logD, logP, thermodynamic solubility, and pK(a). This data set also provides a substantial decoy set for each target consisting of diverse conformations covering the entire active site for all of the 58 CSAR-quality crystal structures. The CSAR data sets (CSAR-NRC HiQ and the 2012 release) provide substantial, publically available, curated data sets for use in parametrizing and validating docking and scoring methods.


Assuntos
Bases de Dados de Produtos Farmacêuticos , Desenho de Fármacos , Simulação de Acoplamento Molecular/métodos , Internet , Ligantes , Ligação Proteica , Conformação Proteica , Relação Estrutura-Atividade
19.
Dent Med Probl ; 60(2): 327-334, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37458399

RESUMO

This systematic review and meta-analysis aimed to summarize the effectiveness of bonded and removable retainers (the Hawley and Essix retainers) in terms of improving occlusal settling (occlusal contact points/areas) after orthodontic treatment. We searched the Cochrane Library, PubMed, CINAHL Plus, and Dental & Oral Sciences Source (DOSS), as well as SIGLE, Google Scholar and ClinicalTrials.gov for eligible studies. We included randomized and non-randomized controlled trials along with cohort studies. Studies that reported occlusal contacts/areas during retention with fixed bonded and removable retainers were included. To assess the quality of the randomized controlled trials (RCTs), the Cochrane Collaboration risk-of-bias (RoB) tool was utilized, whereas the Newcastle-Ottawa Scale (NOS) was used to assess the quality of cohort studies.We included 6 articles in our systematic review after scrutinizing 219 articles and eliminating the illegible ones based on duplication, titles, abstracts, and objectives. Bonded retainers (BRs) allowed faster and better posterior occlusal settling as compared to the Hawley retainer (HR). However, HR showed good occlusal settling in the anterior dental arch. The Essix retainer (ER) showed a decrease in occlusal contact during the retention phase. Meta-analysis showed no statistically significant difference between BRs and removable retainers. In conclusion, HR allowed better overall occlusal settling as compared to other retainers. However, BRs allowed faster settling in the posterior tooth region. The Essix retainer showed poor settling of occlusion. Overall, there is an insufficient number of high-quality RCTs to provide additional evidence, and further high-quality RCTs are needed.


Assuntos
Má Oclusão , Dente , Humanos , Contenções Ortodônticas , Má Oclusão/terapia
20.
Saudi J Biol Sci ; 30(4): 103605, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36950365

RESUMO

Botrytis cinerea is one of the top phytopathogenic fungus which ubiquitously cause grey mold on a variety of horticultural plants. The mechanism of respiration in the fungus occurs within the mitochondria. Mitogenomes serve as a key molecular marker for the investigation of fungal evolutionary patterns. This study aimed at the complete assembly, characterization, and comparative relationship of four mitogenomes of Botrytis cinerea strains including Kst5C, Kst14A, Kst32B, Kst33A, respectively. High throughput sequencing of four mitogenomes allowed the full assembly and annotation of these sequences. The total genome length of these 4 isolates Kst5C Kst14A, Kst32B, Kst33A was 69,986 bp, 77,303 bp, 76,204 bp and 55, 226 bp respectively. The distribution of features represented 2 ribosomal RNA genes,14 respiration encoding proteins, 1 mitochondrial ribosomal protein-encoding gene, along with varying numbers of transfer RNA genes, protein-coding genes, mobile intronic regions and homing endonuclease genes including LAGLIDADG and GIY-YIG domains were found in all four mitogenomes. The comparative analyses performed also decipher significant results for four mitogenomes among fungal isolates included in the study. This is the first report on the detailed annotation of mitogenomes as a proof for investigation of variation patterns present with in the B. cinerea causing grey mold on strawberries in Pakistan. This study will also contribute to the rapid evolutionary analysis and population patterns present among Botrytis cinerea.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA