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1.
Cureus ; 16(3): e57347, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38559538

RESUMEN

Objective To evaluate the relative efficacy of periodontally accelerated osteogenic orthodontics (PAOO) compared to conventional fixed appliances in correcting lower anterior teeth crowding using a non-extraction treatment approach. Material and methods A single-center, two-arm, parallel-group randomized controlled trial was conducted on 38 patients (9 males, 29 females) with moderate crowding. These patients did not require premolar extraction and were randomly allocated into two treatment groups: the PAOO group and the conventional orthodontic treatment group. The Little Irregularity Index (LII) measured crowding intensity on pre-treatment study models. Changes in this index were recorded monthly in both treatment groups. The inter-canine width, inter-second-premolar width, plaque index (PI), gingival index (GI), and papillary bleeding index (PBI) were also measured before and after the leveling and alignment stage. Statistical analysis between the two groups was performed using Mann-Whitney U tests. Results For the LII, the average time for irregularity resolution was three months in the PAOO group, compared to five months in the conventional orthodontic treatment group. Regarding changes in inter-second-premolar width, the PAOO procedure led to a significant decrease in the increase of inter-second-premolar width, with an average increase of +1.52 mm compared to +2.71 mm in the control group. For the GI and PBI, it was found that their values significantly increased with PAOO application, averaging 0.18 and 0.17, respectively, compared to 0.05 and 0.07 in the control group. Conclusions The use of PAOO in orthodontic treatment accelerated the leveling and alignment process by 40%. Changes in the inter-canine width, the inter-second-premolar width, and the status of periodontal tissues were minimal and clinically negligible.

2.
Mob DNA ; 14(1): 17, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37964319

RESUMEN

BACKGROUND: The genome of the obligate biotrophic phytopathogenic barley powdery mildew fungus Blumeria hordei is inflated due to highly abundant and possibly active transposable elements (TEs). In the absence of the otherwise common repeat-induced point mutation transposon defense mechanism, noncoding RNAs could be key for regulating the activity of TEs and coding genes during the pathogenic life cycle. RESULTS: We performed time-course whole-transcriptome shotgun sequencing (RNA-seq) of total RNA derived from infected barley leaf epidermis at various stages of fungal pathogenesis and observed significant transcript accumulation and time point-dependent regulation of TEs in B. hordei. Using a manually curated consensus database of 344 TEs, we discovered phased small RNAs mapping to 104 consensus transposons, suggesting that RNA interference contributes significantly to their regulation. Further, we identified 5,127 long noncoding RNAs (lncRNAs) genome-wide in B. hordei, of which 823 originated from the antisense strand of a TE. Co-expression network analysis of lncRNAs, TEs, and coding genes throughout the asexual life cycle of B. hordei points at extensive positive and negative co-regulation of lncRNAs, subsets of TEs and coding genes. CONCLUSIONS: Our work suggests that similar to mammals and plants, fungal lncRNAs support the dynamic modulation of transcript levels, including TEs, during pivotal stages of host infection. The lncRNAs may support transcriptional diversity and plasticity amid loss of coding genes in powdery mildew fungi and may give rise to novel regulatory elements and virulence peptides, thus representing key drivers of rapid evolutionary adaptation to promote pathogenicity and overcome host defense.

3.
Int Orthod ; 21(4): 100817, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37837842

RESUMEN

OBJECTIVE: To compare the effectiveness of the clear aligners with the traditional fixed appliances in the treatment of premolars extraction complex cases using the American Board of Orthodontics Objective Grading System (ABO-OGS). MATERIAL AND METHODS: A single-centre, 2-parallel groups RCT with two arms. Forty severe crowding patients (14 males, 26 females; mean age: 21.40±2.42) who required four first premolars extraction were included and randomly allocated into two treatment groups: clear aligners therapy group (CAT), and fixed appliances therapy group (FAT). Cases complexities were measured on pre-treatment records using the Discrepancy index (DI). Post-treatment records were evaluated using the American Board of Orthodontics Objective Grading System (ABO-OGS). Two sample t-tests and Fisher's Exact tests were used to test for significant differences between the two groups. The statistical significance was set at P < 0.006 using Bonferroni's correction. RESULTS: For the DI, the mean scores were 32.25 (± 4.33) in the CAT group and 33 (± 7.92) in the FAT group. In the CAT group, the total OGS score ranged between 6-33 points with an average of 17.50(± 7.41), whereas the total score in the FAT group went between 4-30 points with an average of 12.89 (± 6.31) with no significant differences between the two groups (P=0.05). When comparison of the successful cases between the two groups was made, 11 cases received passing scores, and 9 cases received failing scores in the CAT group. Whereas in the FAT group, 17 cases received passing scores, and 3 received a failing score. No statistically significant differences were found in the passing rates between of the CAT and FAT groups (P = 0.421). CONCLUSIONS: According to the ABO-OGS total scores, there was no significant difference between the clear aligners and fixed appliances in the treatment of class I severe crowding cases with first premolars extraction in young adults. There were no differences between the two techniques in the OGS components scores except for the occlusal contacts, which were significantly better with the fixed appliances. When comparing the number of successful and failed cases between the two groups, no significant differences were noted, with the fixed appliances having a 30% higher success rate than the clear aligners, which must be considered clinically when choosing between these two techniques in the complex orthodontic cases treatment.


Asunto(s)
Maloclusión Clase I de Angle , Maloclusión , Aparatos Ortodóncicos Removibles , Femenino , Humanos , Masculino , Adulto Joven , Diente Premolar/cirugía , Maloclusión/terapia , Maloclusión Clase I de Angle/terapia , Aparatos Ortodóncicos Fijos , Resultado del Tratamiento
4.
Cureus ; 15(3): e35733, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36875255

RESUMEN

Introduction Dental crowding is one of the most common types of malocclusions. It can be treated with or without extraction, depending on the severity of the crowding. Extraction-based orthodontic treatments are the preferred treatment option in cases of severe crowding, but they take longer than non-extraction cases. Objective This study aimed to evaluate the dentoalveolar changes following the orthodontic treatment of severely crowded maxillary anterior teeth in adults using self-ligating brackets alone or combined with flapless piezocision. Materials and methods The participants in this study were 63 patients (46 females and 17 males; mean age SD: 19.71 ± 2.74 years) who attended the Department of Orthodontics at the University of Damascus from January 2020 to December 2021. The participants were divided into three groups at random: Group (1): traditional brackets group, Group (2): self-ligating brackets group; and Group (3): self-ligating brackets with flapless piezocision group. Little's Irregularity Index (LII) was measured at five assessment times: before the onset of orthodontic treatment (T0), after one month (T1), after two months (T2), after three months (T3), and at the end of the leveling and alignment phase (T4). The intercanine width (lingual), the intercanine width (cusp), and the canine rotation angle were measured at two assessment times: before the onset of orthodontic treatment (T0) and at the end of the leveling and alignment phase (T4). Results The three studied groups had statistically significant differences in terms of LII during the first three months, and the most significant improvement of LII was in the self-ligating brackets with the piezocision group (P < 0.001). In addition, the intercanine width (cusp) at the end of the leveling and aligning phase revealed greater mean values in both self-ligating brackets groups compared to the traditional brackets group, and the differences were statistically significant (P < 0.001). Otherwise, no statistically significant differences were found at the end of the leveling and aligning phase in the intercanine width (lingual) or the canine rotation angle between the three studied groups (P > 0.05). Conclusion Using self-ligating brackets with flapless piezocision revealed more significant results concerning LII as compared to other groups. Thus, combining these two acceleration methods could get more effective results in aligning severely crowded teeth. Self-ligating brackets, whether used alone or with flapless piezocision, resulted in greater intercanine width at the cusp level. The type of brackets (traditional or self-ligating) did not affect the canine rotation angle.

5.
Cureus ; 14(12): e32879, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36578856

RESUMEN

This review aimed to evaluate the effectiveness of using one or more acceleration methods with self-ligating brackets to accelerate orthodontic tooth movement in adults and the associated effects of these interventions. An electronic search of the following databases (PubMed, Scopus, Google Scholar, EMBASE) was performed (From January 1990 to November 2021). ClinicalTrials.gov and the International Clinical Trials Registry Platform were also electronically searched to find any unpublished studies and ongoing trials. The selected randomized controlled trials (RCTs) involved adult patients treated using self-ligating brackets combined with one or more acceleration methods compared with self-ligating brackets or conditional brackets alone. The risk of bias was assessed using Cochrane's risk of bias tool. A total of seven RCTs and one controlled clinical trial (CCT) were included in this review. Combining self-ligating brackets with flapless corticotomy, low-level laser therapy (LLLT), and infrared light accelerated orthodontic movement by 43% and 50% for surgical methods, 20-50% for LLLT, and 22% for infrared light. Regarding side effects on periodontal tissues, neither flapless corticotomy nor low-frequency vibrational forces caused any damage. Combining self-ligating brackets and flapless corticotomy, low-level laser, or infrared light effectively accelerated orthodontic movement by 20% to 50 %. In contrast, the combination of self-ligating brackets with vibrational forces did not affect speeding tooth movement. The acceleration methods did not have any side effects on the periodontal tissues, but the available evidence was insufficient. There is a need for further primary research regarding the effectiveness of combining self-ligating brackets with acceleration methods and the possible untoward side effects.

6.
Cureus ; 14(6): e26467, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35785015

RESUMEN

Introduction The pain and discomfort associated with orthodontic treatment are considered undesirable complications which may negatively affect the patient's cooperation and reduce the efficiency of orthodontic treatment. This trial aimed to assess patient-centered outcomes in the treatment of class I malocclusion with severe crowding using self-ligating brackets (SLBs) with or without an acceleration procedure (piezocision) compared to the traditional brackets (TBs) in a three-arm trial. Materials and Methods Sixty-six patients (51 females, 15 males; mean age ± SD: 20.08 ± 2.61 years) attending the Department of Orthodontics, the University of Damascus, Damascus (Syria) from April 2019 to October 2020 participated in this study. The patients were randomly allocated to three groups: the TBs s group (n = 22; mean age ± SD: 18.72 ± 2.42), the SLBs group (n = 22; mean age ± SD: 20.48 ± 2.84), and the SLBs with the piezocision group (SLBs+P; n = 22; mean age ± SD: 19.17 ± 2.59). Patient-centered outcomes were assessed using two standardized questionnaires depending on visual analog scales (VAS) for the majority of the questions and a binary scale (Yes/No) for the last two questions in the second questionnaire. The levels of pain, discomfort, swelling, difficulties with mastication, swallowing, and jaw movement restriction were measured at five assessment times: one day (T1), 3 days (T2), 7 days (T3), 14 days (T4), and 28 days (T5) after the beginning of treatment. The satisfaction levels, acceptance to undergo the applied treatment again, and willingness to advise a friend to receive similar treatment were measured at the last assessment time (T5). One-way ANOVA test or its alternative nonparametric test (i.e., Kruskal-Wallis test) was utilized to compare the three groups. Results There were statistically significant differences between the three groups regarding pain, discomfort, swelling, difficulties with mastication, problems with swallowing, and jaw movement restriction during the first three assessment times only (T1, T2, and T3; P < 0.001). The differences were mainly between the SLBs+P group and the other two groups, where the mean values were greater in the SLBs+P group. Otherwise, there were no significant statistical differences between the SLBs and the TBs groups. Concerning patients' satisfaction with the provided treatment, a statistically significant difference between the three groups was detected after 28 days (T5; P < 0.001). The SLBs+P group showed the lowest mean values, whereas there were no significant differences between the two other groups. Conclusion The levels of pain and discomfort, swelling, difficulties in mastication and swallowing, and restriction of jaw movement were greater in SLBs with the piezocision group compared to the sole use of SLBs or TBs in the first week only. The patients showed a high level of satisfaction with the applied therapeutic procedures, which means that SLBs alone or in combination with piezocision can be an accepted treatment modality by patients in the acceleration of orthodontic tooth movement.

7.
Cureus ; 14(3): e22793, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35261839

RESUMEN

Objective This study aimed to evaluate and compare the levels of pain, discomfort, and functional impairments between slow and rapid maxillary expansion (RME) in treating skeletal maxillary constriction in the adolescence period (i.e., between 12 and 16 years). Materials and methods The study sample consisted of 52 patients (21 males and 31 females) with maxillary skeletal constriction in the posterior region. The patients were randomly distributed into either RME (26 patients, with a mean age of 13.87 (± 1.31) years) or slow maxillary expansion group (SME, 26 patients, with a mean age of 14.31 (± 1.19) years). The levels of pain, discomfort, and functional difficulties were assessed after 24 hours (T1), 7 days (T2), 15 days (T3), one month (T4), and four months (T5) following the onset of the expansion procedure. Results Patients in the RME group encountered significantly greater levels of pain and discomfort than those in the SME group at T1, T2, and T3 (p>0.001). Chewing and swallowing difficulties were significantly greater in the RME group at T1, T2, T3, and T4 (P≤0.001). The pressure on soft tissue was greater in the RME group at T2 and T3 (p>0.001). After four months (T5), the levels of pain and discomfort decreased to their lowest levels, as well as the difficulties of chewing and swallowing, and the pressure on soft tissue were almost non-existent in both groups. Conclusion Patients treated with the removable slow maxillary expander reported lower levels of pain and discomfort, fewer chewing and swallowing difficulties, and less pressure on soft tissues than those treated with the bonded rapid maxillary expander. These difficulties gradually decreased over time in both groups. The lower levels of pain and discomfort may make the SME an effective and comfortable treatment alternative for adolescents with skeletal maxillary constriction.

8.
J World Fed Orthod ; 11(1): 3-11, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34688577

RESUMEN

INTRODUCTION: The lengthy period of time required is one of the main reasons patients refuse orthodontic treatment. In addition, treatment may have negative effects on periodontal tissues. OBJECTIVE: This study aimed to evaluate the overall time needed for leveling and alignment and the periodontal indices in adult patients with severe crowding. Patients were treated using either self-ligating brackets associated with flapless corticotomy (SLBs + FC group), self-ligating brackets alone (SLBs group), or conventional brackets (CBs group) alone. MATERIALS AND METHODS: A total of 57 adult patients (10 male patients, 47 female patients) referred to the Department of Orthodontics, the University of Damascus Dental School from August 2018 to March 2019, were enrolled in this trial. The patients were randomly allocated to 1 of 3 groups: CBs (mean age: 19.62 ± 2.42 years), SLBs (mean age: 19.98 ± 2.84 years), or SLBs + FC (mean age: 20.67 ± 2.59 years). The overall alignment time for the upper anterior teeth was calculated. The following periodontal parameters were measured at 5 assessment times: plaque index, gingival index, papillary bleeding index, and probing depth. RESULTS: The average leveling and alignment time was 81.89 ± 9.49 days, 123 ± 10.69 days, and 165.25 ± 13.05 days for the SLBs + FC group, the SLBs group, and the CBs group, respectively. A significant reduction in the overall alignment duration was found in the SLBs + FC group by 50%, and in the SLBs group by 25%, compared to the control group, with a statistically significant difference among the 3 groups (P < 0.001). There were statistically significant differences in the periodontal indices (except probing depth) after 1 month, with values greater in the SLBs + FC group (P < 0.05). CONCLUSIONS: Using self-ligating brackets in combination with flapless corticotomy may be effective in accelerating upper dental decrowding in adult patients, with a reduction of 50% of the normal treatment time using traditional brackets. Using self-ligating brackets alone reduced treatment time by 25%. The adjunctive flapless corticotomy did not cause clinically negative effects on the periodontal tissues.


Asunto(s)
Maloclusión , Soportes Ortodóncicos , Adolescente , Adulto , Índice de Placa Dental , Femenino , Humanos , Masculino , Maloclusión/cirugía , Diseño de Aparato Ortodóncico , Soportes Ortodóncicos/efectos adversos , Índice Periodontal , Adulto Joven
9.
ISME J ; 16(1): 138-148, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34282282

RESUMEN

The host range of parasites is an important factor in assessing the dynamics of disease epidemics. The evolution of pathogens to accommodate new hosts may lead to host range expansion, a process the molecular bases of which are largely enigmatic. The fungus Sclerotinia sclerotiorum has been reported to parasitize more than 400 plant species from diverse eudicot families while its close relative, S. trifoliorum, is restricted to plants from the Fabaceae family. We analyzed S. sclerotiorum global transcriptome reprogramming on hosts from six botanical families and reveal a flexible, host-specific transcriptional program. We generated a chromosome-level genome assembly for S. trifoliorum and found near-complete gene space conservation in two representative strains of broad and narrow host range Sclerotinia species. However, S. trifoliorum showed increased sensitivity to the Brassicaceae defense compound camalexin. Comparative analyses revealed a lack of transcriptional response to camalexin in the S. trifoliorum strain and suggest that regulatory variation in detoxification and effector genes at the population level may associate with the genetic accommodation of Brassicaceae in the Sclerotinia host range. Our work proposes transcriptional plasticity and the co-existence of signatures for generalist and polyspecialist adaptive strategies in the genome of a plant pathogen.


Asunto(s)
Señales (Psicología) , Especificidad del Huésped , Humanos , Enfermedades de las Plantas/microbiología , Plantas/microbiología , Transcriptoma
10.
mBio ; 12(6): e0177421, 2021 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-34724831

RESUMEN

Bacillus velezensis is considered as a model species belonging to the so-called Bacillus subtilis complex that evolved typically to dwell in the soil rhizosphere niche and establish an intimate association with plant roots. This bacterium provides protection to its natural host against diseases and represents one of the most promising biocontrol agents. However, the molecular basis of the cross talk that this bacterium establishes with its natural host has been poorly investigated. We show here that these plant-associated bacteria have evolved a polymer-sensing system to perceive their host and that, in response, they increase the production of the surfactin-type lipopeptide. Furthermore, we demonstrate that surfactin synthesis is favored upon growth on root exudates and that this lipopeptide is a key component used by the bacterium to optimize biofilm formation, motility, and early root colonization. In this specific nutritional context, the bacterium also modulates qualitatively the pattern of surfactin homologues coproduced in planta and forms mainly variants that are the most active at triggering plant immunity. Surfactin represents a shared good as it reinforces the defensive capacity of the host. IMPORTANCE Within the plant-associated microbiome, some bacterial species are of particular interest due to the disease protective effect they provide via direct pathogen suppression and/or stimulation of host immunity. While these biocontrol mechanisms are quite well characterized, we still poorly understand the molecular basis of the cross talk these beneficial bacteria initiate with their host. Here, we show that the model species Bacillus velezensis stimulates the production of the surfactin lipopeptide upon sensing pectin as a cell surface molecular pattern and upon feeding on root exudates. Surfactin favors bacterial rhizosphere fitness on one hand and primes the plant immune system on the other hand. Our data therefore illustrate how both partners use this multifunctional compound as a unique shared good to sustain a mutualistic interaction.


Asunto(s)
Bacillus/metabolismo , Lipopéptidos/metabolismo , Pectinas/metabolismo , Exudados de Plantas/metabolismo , Raíces de Plantas/metabolismo , Raíces de Plantas/microbiología , Simbiosis , Bacillus/genética , Interacciones Microbiota-Huesped , Rizosfera , Microbiología del Suelo
11.
BMC Public Health ; 21(1): 1207, 2021 06 24.
Artículo en Inglés | MEDLINE | ID: mdl-34162351

RESUMEN

INTRODUCTION: Europe has been experiencing a flow of refugees and asylum seekers driven by conflicts or poverty. Their oral health is often neglected despite its clear impact on quality of life. OBJECTIVE: To explore the status of oral health among refugees and asylum seekers groups by examining the available literature and to determine which evidence exists regarding the problems they face in terms of oral health. METHODS: The current paper followed PRISMA guidelines. A scoping review methodology was followed to retrieve 2911 records from five databases and grey literature. Twelve articles met the following inclusion criteria: experimental research concentrated on the oral and dental health of refugees and/or asylum seekers between 1995 and 2020 in English. Analysis was both descriptive and thematic, whilst a critical appraisal was applied using the Critical Appraisal Skills Program (CASP). RESULTS: Seven studies (58,3%) were quantitative, while five studies (41,6%) were qualitative. In general, the quality of most of the studies (83.3%) was good. Limited access to oral health care services was shown with a higher prevalence of oral diseases compared to the native populations of the host countries. Approaches to improve oral health have been implemented in some studies and have shown positive outcomes. CONCLUSIONS: Oral health care strategies should consider the oral health problems facing refugees in Europe, and oral health promotion campaigns are essential to give adequate guidance on how to access oral health care in the host countries.


Asunto(s)
Refugiados , Europa (Continente)/epidemiología , Accesibilidad a los Servicios de Salud , Humanos , Salud Bucal , Calidad de Vida
12.
Trends Plant Sci ; 26(8): 780-795, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33674173

RESUMEN

Pathogens produce effectors to overcome plant immunity, thereby threatening crop yields and global food security. Large-scale interactomic studies have revealed that pathogens from different kingdoms of life target common plant proteins during infection, the so-called effector hubs. These hubs often play central roles in numerous plant processes through their ability to interact with multiple plant proteins. This ability arises partly from the presence of intrinsically disordered domains (IDDs) in their structure. Here, we highlight the role of the TEOSINTE BRANCHED1/CYCLOIDEA/PROLIFERATING CELL FACTOR (TCP) and JASMONATE-ZIM DOMAIN (JAZ) transcription regulator families as plant signaling and effector hubs. We consider different evolutionary hypotheses to rationalize the existence of diverse effectors sharing common targets and the possible role of IDDs in this interaction.


Asunto(s)
Inmunidad de la Planta , Plantas , Regulación de la Expresión Génica de las Plantas , Inmunidad de la Planta/genética , Proteínas de Plantas/genética , Plantas/genética , Transducción de Señal
13.
Materials (Basel) ; 14(5)2021 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-33671062

RESUMEN

The current study was designed to assess the effect of different concentrations of silica oxide nanoparticles (SiO2NPs) (0, 30, 60, and 90 ppm) as foliar applications under three irrigation regimes i.e., irrigation every 3 days (IR3, control), irrigation every 6 days (IR6), and irrigation every 9 days (IR9) on growth, yield and certain metabolites of rice (Oryza sativa L. cv. EHR1). To achieve such a goal, 2 field experiments were conducted during the 2018 and 2019 seasons at the Experimental Farm of Rice Research and Training Center (RRTC), Sakha Agricultural Station, Kafr El-sheik, Egypt. Firstly, the as-prepared nanoparticles of SiO2 were prepared from useless materials (RHs) which are considered as one of the bio burdens on the environment via treating with HCl and followed by drying and calcination. Consequently, the synthesis was examined by making use of advanced tools such as X-ray diffraction (XRD), transmission electron microscopy (TEM), dynamic light scattering (DLS) for illustrating the hydrodynamic particle size of SiO2NPs and scanning electron microscopy (SEM). The nanoparticles were formed with nearly spherical shape and small size. The results indicated that leaf area index, dry matter production, the number of panicles/m2, the number of filled grains/ panicles, 1000 grain weight, grain yield, and biological yield as well as chlorophyll content have witnessed a significant increase under irrigated application every 3 and 6 days. Whilst a prolonged irrigation regime up to 9 days recorded a remarkable decline in the aforementioned characteristics except for the number of unfilled grains/panicle which increased considerably in both seasons. On the other hand, proline concentration and the activity of the antioxidant enzymes were increased in both irrigated treatments every 6 and 9 days compared with control treatment (irrigation every 3 days). The foliar supplementations of (SiO2NPs) contributed to ameliorating all the aforementioned characteristics progressively up to the dosage of 90 ppm compared to control treatment (no Si/NPS application) in both seasons. Invariably, growth and yield parameters in water-stressed plants treated with SiO2NPs were higher than those in water-stressed plants without SiO2NPs addition. Based on that, it could be concluded that the foliar application of SiO2NPs can mitigate the adverse effect of water stress on rice plants.

14.
Proc Natl Acad Sci U S A ; 118(2)2021 01 12.
Artículo en Inglés | MEDLINE | ID: mdl-33443212

RESUMEN

Agrobacterium spp. are important plant pathogens that are the causative agents of crown gall or hairy root disease. Their unique infection strategy depends on the delivery of part of their DNA to plant cells. Thanks to this capacity, these phytopathogens became a powerful and indispensable tool for plant genetic engineering and agricultural biotechnology. Although Agrobacterium spp. are standard tools for plant molecular biologists, current laboratory strains have remained unchanged for decades and functional gene analysis of Agrobacterium has been hampered by time-consuming mutation strategies. Here, we developed clustered regularly interspaced short palindromic repeats (CRISPR)-mediated base editing to enable the efficient introduction of targeted point mutations into the genomes of both Agrobacterium tumefaciens and Agrobacterium rhizogenes As an example, we generated EHA105 strains with loss-of-function mutations in recA, which were fully functional for maize (Zea mays) transformation and confirmed the importance of RolB and RolC for hairy root development by A. rhizogenes K599. Our method is highly effective in 9 of 10 colonies after transformation, with edits in at least 80% of the cells. The genomes of EHA105 and K599 were resequenced, and genome-wide off-target analysis was applied to investigate the edited strains after curing of the base editor plasmid. The off-targets present were characteristic of Cas9-independent off-targeting and point to TC motifs as activity hotspots of the cytidine deaminase used. We anticipate that CRISPR-mediated base editing is the start of "engineering the engineer," leading to improved Agrobacterium strains for more efficient plant transformation and gene editing.


Asunto(s)
Agrobacterium/genética , Proteínas Asociadas a CRISPR/genética , Edición Génica/métodos , Agrobacterium tumefaciens/genética , Proteínas Asociadas a CRISPR/metabolismo , Sistemas CRISPR-Cas/genética , Sistemas CRISPR-Cas/fisiología , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genética , ADN de Plantas/genética , Genes de Plantas/genética , Genoma de Planta/genética , Mutagénesis/genética , Mutación/genética , Zea mays/genética
15.
J World Fed Orthod ; 10(1): 3-8, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33422476

RESUMEN

BACKGROUND: No clinical studies have evaluated shear bond strength and the clinical failure rates of the rebonded metallic brackets following different enamel-reconditioning methods. The objective of the study was to compare the in vivo clinical failure rate and the in vitro rebond strength of bonded brackets following two enamel surface preparation methods. METHODS: For the in vitro study, 45 extracted human premolars were etched; brackets were bonded using light-cured composite resin. Forty-five premolars were divided into three groups (15 in each group): the initial bonding group (IB group), the rebonding group in which enamel was reconditioned using sandblasting before acid etching (SBE group), and the rebonding group in which enamel was reconditioned using acid etching only (E group). For the in vivo study, 80 premolars in 20 patients (13-18 years old) were rebonded using the same procedures in the SBE group and E group. The two methods were used in all patients using a split-mouth design. The number of failing brackets was quantified over 6 months. Differences were statistically analyzed by one-way analysis of variance, followed by post hoc tests. RESULTS: The mean shear bond strength for the IB, SBE, and E groups was 19.38, 22.37, and 17.31 MPa, respectively. A significant difference was observed in the bond strength of the three evaluated groups (P < 0.001). The differences in the bond strength were significant between the IB group and the SBE group, as well as between the SBE group and the E group. The clinical failure rate for bonded brackets was 10% in the SBE group, and 25% in the E group and this difference was statistically significant (P < 0.001). CONCLUSIONS: Reconditioning of enamel surfaces using both intraoral air abrasion and etching in the rebonding process led to higher rebond strength than using acid etching alone and even higher than the initial brackets bonding. This trial was retrospectively registered at ClinicalTrials.gov (ID: NCT04606043).


Asunto(s)
Soportes Ortodóncicos , Grabado Ácido Dental , Adolescente , Resinas Compuestas , Humanos , Cementos de Resina , Resistencia al Corte
16.
Mol Plant Pathol ; 22(1): 31-47, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33111422

RESUMEN

Sclerotinia sclerotiorum is a notorious generalist plant pathogen that threatens more than 600 host plants, including wild and cultivated species. The molecular bases underlying the broad compatibility of S. sclerotiorum with its hosts is not fully elucidated. In contrast to higher plants and animals, alternative splicing (AS) is not well studied in plant-pathogenic fungi. AS is a common regulated cellular process that increases cell protein and RNA diversity. In this study, we annotated spliceosome genes in the genome of S. sclerotiorum and characterized their expression in vitro and during the colonization of six host species. Several spliceosome genes were differentially expressed in planta, suggesting that AS was altered during infection. Using stringent parameters, we identified 1,487 S. sclerotiorum genes differentially expressed in planta and exhibiting alternative transcripts. The most common AS events during the colonization of all plants were retained introns and the alternative 3' receiver site. We identified S. sclerotiorum genes expressed in planta for which (a) the relative accumulation of alternative transcripts varies according to the host being colonized and (b) alternative transcripts harbour distinct protein domains. This notably included 42 genes encoding predicted secreted proteins showing high-confidence AS events. This study indicates that AS events are taking place in the plant pathogenic fungus S. sclerotiorum during the colonization of host plants and could generate functional diversity in the repertoire of proteins secreted by S. sclerotiorum during infection.


Asunto(s)
Empalme Alternativo , Ascomicetos/genética , Genoma Fúngico/genética , Enfermedades de las Plantas/microbiología , Plantas/microbiología , Ascomicetos/fisiología , Isoformas de Proteínas , Análisis de Secuencia de ARN
17.
Mol Plant Microbe Interact ; 33(7): 880-883, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32310704

RESUMEN

The fungus Myriosclerotinia sulcatula is a close relative of the notorious polyphagous plant pathogens Botrytis cinerea and Sclerotinia sclerotiorum but exhibits a host range restricted to plants from the Carex genus (Cyperaceae family). To date, there are no genomic resources available for fungi in the Myriosclerotinia genus. Here, we present a chromosome-scale reference genome assembly for M. sulcatula. The assembly contains 24 contigs with a total length of 43.53 Mbp, with scaffold N50 of 2,649.7 kbp and N90 of 1,133.1 kbp. BRAKER-predicted gene models were manually curated using WebApollo, resulting in 11,275 protein-coding genes that we functionally annotated. We provide a high-quality reference genome assembly and annotation for M. sulcatula as a resource for studying evolution and pathogenicity in fungi from the Sclerotiniaceae family.


Asunto(s)
Ascomicetos , Carex (Planta)/microbiología , Genoma Fúngico , Enfermedades de las Plantas/microbiología , Ascomicetos/genética , Ascomicetos/patogenicidad , Cromosomas Fúngicos/genética
18.
Mol Plant Microbe Interact ; 33(6): 782-786, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32150511

RESUMEN

Powdery mildew of sweet pepper (Capsicum annuum) is an economically important disease. It is caused by Leveillula taurica, an obligate biotrophic ascomycete with a partly endophytic mycelium and haustoria, i.e., feeding structures formed in the mesophyll cells of infected host plant tissues. The molecular basis of its pathogenesis is largely unknown because genomic resources only exist for epiphytically growing powdery mildew fungi with haustoria formed exclusively in epidermal cells of their plant hosts. Here, we present the first reference genome assembly for an isolate of L. taurica isolated from sweet pepper in Hungary. The short read-based assembly consists of 23,599 contigs with a total length of 187.2 Mbp; the scaffold N50 is 13,899 kbp and N90 is 3,522 kbp; and the average GC content is 39.2%. We detected at least 92,881 transposable elements covering 55.5 Mbp (30.4%). BRAKER predicted 19,751 protein-coding gene models in this assembly. Our reference genome assembly of L. taurica is the first resource to study the molecular pathogenesis and evolution of a powdery mildew fungus with a partly endophytic lifestyle.


Asunto(s)
Ascomicetos/genética , Capsicum/microbiología , Genoma Fúngico , Enfermedades de las Plantas/microbiología , Composición de Base , Mapeo Contig , Elementos Transponibles de ADN
19.
Plant Physiol Biochem ; 141: 332-342, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31207494

RESUMEN

Plant-parasitic nematodes cause major agricultural losses worldwide. Examining the molecular mechanisms underlying plant-nematode interactions and how plants respond to different invading pathogens is attracting major attention to reduce the expanding gap between agricultural production and the needs of the growing world population. This review summarizes the most recent developments in plant-nematode interactions and the diverse approaches used to improve plant resistance against root knot nematode (RKN). We will emphasize the recent rapid advances in genome sequencing technologies, small interfering RNA techniques (RNAi) and targeted genome editing which are contributing to the significant progress in understanding the plant-nematode interaction mechanisms. Also, molecular approaches to improve plant resistance against nematodes are considered.


Asunto(s)
Interacciones Huésped-Parásitos , Nematodos/patogenicidad , Raíces de Plantas/parasitología , Plantas/parasitología , Animales , Mapeo Cromosómico , Biología Computacional/métodos , Femenino , Genoma de Planta , Masculino , Enfermedades de las Plantas/parasitología , Fenómenos Fisiológicos de las Plantas , Raíces de Plantas/genética , Plantas/genética , Plantas Modificadas Genéticamente/parasitología , Sitios de Carácter Cuantitativo , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Transcriptoma , Virulencia/genética
20.
PLoS One ; 14(5): e0216301, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31067255

RESUMEN

In liver fibrosis, conversion of fibroblasts to profibrogenic myofibroblasts significantly drives the development of the disease. A crucial role of cyclic adenosine monophosphate (cAMP) in regulation of fibroblast function has been reported. Increase in cAMP levels has been found to decrease fibroblast proliferation, inhibit their conversion to myofibroblast, and stimulate their death. cAMP is generated by adenyl cyclase (AC), and degraded by cyclic nucleotide phosphodiesterase (PDE). In this study, the antifibrotic effect of a PDE inhibitor, cilostazol (Cilo), on a rat model of liver fibrosis induced by thioacetamide (TAA) was investigated. Four groups of rats were used; the first group received the vehicles and served as the normal control group, while liver fibrosis was induced in the other groups using (TAA, 200 mg/kg/biweekly for 8 successive weeks, ip). The last two groups were treated with Cilo (50 and 100 mg/kg/day, po, respectively). Induction of liver fibrosis in TAA-treated rats was observed as evidenced by the biochemical and histopathological findings. On the other hand, a potent antifibrotic effect was observed in the groups treated with Cilo, with preference to the higher dose. In these groups, a significant increase in the liver content of cAMP was demonstrated that was accompanied by reduction in the hepatic expression of key fibrogenic cytokines, growth factors, and inflammatory biomarkers, including interleukin-6, tumor necrosis factor-alpha, nuclear factor kappa B, and transforming growth factor-beta as compared to TAA group. Moreover, amelioration of TAA-induced oxidative stress and apoptosis in the liver has been observed. These findings reveal the antifibrotic effect of Cilo against TAA-induced liver fibrosis in rats, and suggest regulation of cAMP pathway, together with the modulation of oxidative stress, inflammation, and apoptosis as mechanistic cassette underlines this effect.


Asunto(s)
Cilostazol/uso terapéutico , Cirrosis Hepática/tratamiento farmacológico , Animales , Apoptosis/efectos de los fármacos , Biomarcadores/análisis , AMP Cíclico/metabolismo , Inflamación/tratamiento farmacológico , Hígado/metabolismo , Cirrosis Hepática/inducido químicamente , Estrés Oxidativo/efectos de los fármacos , Ratas , Tioacetamida/toxicidad , Regulación hacia Arriba
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