Search Results (72)

Grapevine breeding programs face difficulties in preserving germplasm, especially from species and interspecific hybrids, since most collections are maintained in the field and exposed to biotic and abiotic stress, which can lead to material loss. The Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF) Grapevine Breeding Program faces similar challenges, limiting studies on hybrids resistant to the nematode Pratylenchus brachyurus and downy mildew (Plasmopara viticola), which are valuable for genetic improvement. This study aimed to implement in vitro conservation under minimal growth conditions for interspecific hybrids of Vitis spp. from the UENF program. The protocol followed a completely randomized design in a 2 × 2 × 3 factorial scheme: two hybrids (CH1.2 and CH1.3), two temperatures (18 ± 1 °C and 27 ± 2 °C), and three sucrose concentrations (10, 20, and 30 g L⁻¹), over 180 days of in vitro culture. The results showed that conservation of the UENF hybrids is feasible using nodal segments as explants, at 18 ± 2 °C and 10 g L⁻¹ of sucrose, for up to four months. This protocol may also be applied to other Vitis spp., contributing to the preservation and continued study of valuable germplasm. Full article

The introduction of new ornamental species and cultivars is one of the hallmarks of innovation in global floriculture. Brunfelsia uniflora, a subshrub native to Brazil, has white, lilac, and blue flowers on the same plant, in addition to a distinctive fragrance. As it is a wild species, technologies such as large-scale clonal propagation of superior genotypes are still scarce, limiting its supply to the flower market. Therefore, a successful micropropagation protocol was developed for B. uniflora using nodal segments and shoot tips as initial explants. In the multiplication phase, the use of 6-benzylaminopurine produced the highest multiplication rates (10.3–10.9 shoots/explant) and the number of leaves in the shoots. In vitro shoot rooting using MS medium with reduced macronutrient concentrations and supplemented with IBA resulted in a 91.7% rooting rate. The greatest difficulty in micropropagating this species was the high percentage of shoots that developed calli. The highest percentage of callus formation occurred with the addition of auxins at high concentrations (1.0 and 1.5 mg L⁻¹). Even so, the shoots and plantlets were acclimatized, demonstrating the effectiveness of this technique for the production of B. uniflora plantlets. Full article

Objective: The objective of this study was to develop and assess the clinical feasibility of auto-segmentation and auto-planning methodologies for automated radiotherapy in prostate cancer. Methods: A total of 166 patients were used to train a 3D Unet model for segmentation of the gross tumor volume (GTV), clinical tumor volume (CTV), nodal CTV (CTVnd), and organs at risk (OARs). Performance was assessed by the Dice similarity coefficient (DSC), the Recall, Precision, Volume Ratio (VR), the 95% Hausdorff distance (HD95%), and the volumetric revision degree (VRD). An auto-planning network based on a 3D Unet was trained on 77 treatment plans derived from the 166 patients. Dosimetric differences and clinical acceptability of the auto-plans were studied. The effect of OAR editing on dosimetry was also evaluated. Results: On an independent set of 50 cases, the auto-segmentation process took 1 min 20 s per case. The DSCs for GTV, CTV, and CTVnd were 0.87, 0.88, and 0.82, respectively, with VRDs ranging from 0.09 to 0.14. The segmentation of OARs demonstrated high accuracy (DSC ≥ 0.83, Recall/Precision ≈ 1.0). The auto-planning process required 1–3 optimization iterations for 50%, 40%, and 10% of cases, respectively, and exhibited significant better conformity (p ≤ 0.01) and OAR sparing (p ≤ 0.03) while maintaining comparable target coverage. Only 6.7% of auto-plans were deemed unacceptable compared to 20% of manual plans, with 75% of auto-plans considered superior. Notably, the editing of OARs had no significant impact on doses. Conclusions: The accuracy of auto-segmentation is comparable to that of manual segmentation, and the auto-planning offers equivalent or better OAR protection, meeting the requirements of online automated radiotherapy and facilitating its clinical application. Full article

Background: Prostate cancer is a major cause of cancer-related mortality among men, with approximately 15% of newly diagnosed patients having pelvic lymph node metastasis (PLNM). For this reason, PLNM identification before localized PCa treatment would significantly impact treatment planning, clinical judgment, and patient outcome prediction. Radiomics has gained popularity for its ability to predict tumor behavior and prognosis without invasive procedures. Magnetic resonance imaging (MRI) is widely used in radiomic workups, particularly for prostate cancer. This study aims to predict lymph node invasion in prostate cancer patients using clinical information and mp-MRI radiomics features extracted from the suspicious nodule, prostate gland, and periprostatic adipose tissue (PPAT). Methods: A retrospective review of 85 patients who underwent mp-MRI at our radiology department between 2016 and 2022 was conducted. This study included patients who underwent prostatectomy and lymphadenectomy with complete histological examination and previous staging mp-MRI and were divided into two groups based on lymph node status (positive/negative). Data were collected from each patient, including clinical information, radiomics, and semantic data (such as tumor MRI characteristics, histological tumor details, and lymph node status (LNS)). MRI exams were conducted using a 1.5-T system and were used to study the prostate gland. A three-year resident manually segmented the prostate nodule, prostatic gland, and periprostatic tissue using an open-source segmentation program. A random forest (RF) machine learning model was developed and tested using Chat-GPT version 4.0 software. The model’s performance in predicting LNS was assessed using accuracy, precision, recall, F1 score, and area under the curve (AUC) receiver operating characteristic (ROC), with sensitivity and specificity evaluated using DeLong’s test. Results: Random forest demonstrated the best performance in prediction considering features extracted from DWI nodules (67% of accuracy, 0.83 AUC), from T2 fat (78% of accuracy, 0.86 AUC), and from T2 glands (78% of accuracy, 0.97 AUC). The combination of the three sequences in the nodule evaluation was more accurate compared with the single sequences (88%). Combining all the nodule features with gland and PPAT features, an accuracy of 89% with AUC near 1 was obtained. Compared with the analysis of the nodule and the PPAT, the whole-gland evaluation had the best performance (p ≤ 0.05) in predicting LNS when compared with the nodule. Conclusions: Precise nodal staging is essential for PCa patients’ prognosis and therapeutic strategy. When compared with a radiologist’s assessment, radiomics models enhance the diagnostic accuracy of lymph node staging for prostate cancer. Although data are still lacking, deep learning models may be able to further improve on this. Full article

Extracting nodal features is crucial for analyzing rock structure stability and plays a significant role in designing engineering projects. This study presents an enhanced version of the FraSegNet algorithm, focusing on improving its ability to identify nodal features in images. The updated FraSegNet incorporates the ResNet101 backbone and integrates the Squeeze-and-Excitation (SE) attention mechanism, enabling better concentration on key nodal characteristics. The primary improvements are as follows: (1) Multi-scale feature extraction: Leveraging the ResNet101 architecture for the effective extraction of detailed information from nodal images. (2) Better attention mechanisms: The SE module focuses on nodal regions, resulting in clearer and more refined feature representations. (3) Dynamic learning strategies: I incorporation of cosine annealing and warm-up techniques to optimize training efficiency. The algorithm was validated with the Barton–Bandis model and Hoek–Brown criterion. The experimental results demonstrate its superior performance, achieving 97.1% accuracy in nodal feature detection with an average error of only 1.5% compared to the rock mass parameter. This small error proves the model works well. FraSegNet offers accurate segmentation and precise geometric parameter extraction, making it a valuable tool for advancing rock stability analysis and practical applications in rock mechanics. Full article

“GiSelA 17” (Prunus canescens × Prunus avium) is a novel cherry clonal rootstock with the ability to bear fruit early and resist replant situations, and it has a high tolerance to the menaces of Prunus dwarf virus (PDV) and Prunus necrotic ring spot virus (PNRSV). In this study, two kinds of explants were taken, i.e., shoot tip (E1) (10 mm) and nodal segment (E2) (15 mm) explants. Five different sterilant regimes using sodium hypochlorite, mercuric chloride, and ethyl alcohol were employed to assess surface sterilization. Two types of media, namely Murashige and Skoog (MS) and Woody Plant Medium (WPM), and twelve and six plant growth regulator combinations with benzyl amino purine (BAP) and indole-3-butyric acid (IBA) were used, respectively, for the establishment and proliferation steps. The results show that maximum culture asepsis (75.33%) was obtained with shoot tips (E1) using 0.05% HgCl₂ for 5 min + 70% ethanol for 10 s (S4), and maximum explant survival (80.33%) was observed in 0.1% HgCl₂ for 5 min (S1) for shoot tips (E1). The maximum establishment rate (83.33%) was found in shoot tips (E1) in MS medium with BAP + IBA (1 + 0.01 mg/L) during the establishment step, with a maximum proliferation rate of 92.00% obtained in MS and BAP (0.75 mg/L). Inferior establishment results (26.66%) were obtained in nodal segments (E2) using WPM and BAP + IBA (1.50 + 0.01 mg/L), with a low proliferation rate (68.66%) in WPM and BAP + IBA (0.25 + 0.01 mg/L). Nonetheless, our research is the first in vitro study on “GiSelA 17” rootstock that focuses on generating the best quality planting material for commercial cherry production. Full article

Potatoes, a vital global food crop, have shown remarkable adaptability, significantly contributing to food security. Technological advancements now enable their cultivation from soil-based systems to liquid synthetic nutrient media, even in artificial closed environments without natural light or fertile soil. This study examined the effects of Benzylaminopurine (BAP) and Kinetin (Kin) at concentrations ranging from 0 to 5 mg/L and sucrose concentrations ranging from 20 to 120 g/L on in vitro tuberization, focusing on microtuber size, weight, and tuberization rate. Nodal segments from virus-free ‘Red Scarlet’ in vitro potato plantlets were used as explants. These explants were cultured on Murashige and Skoog (MS) medium solidified with 0.5% agar. The study also compared minituber production efficiency under soil-based greenhouse and aeroponic conditions. The highest in vitro potato tuberization rate (90%) was achieved with 80 g/L sucrose and 3.0 mg/L BAP. After induction, virus-free microtubers were transferred to both greenhouse conditions and aeroponic systems for further assessment of minituber production and biochemical composition. These findings demonstrate the potential of aeroponics as a superior method for producing high-quality, pathogen-free minitubers. Aeroponics resulted in significantly higher minituber yields compared to soil-based greenhouse systems, offering a scalable and efficient solution for seed production. Full article

Establishing appropriate boundary conditions is essential for developing high-accuracy hydrodynamic models. However, this task is particularly challenging in topographically varying urban domains without monotonous slopes due to insufficient boundary information. This study investigates five different boundary conditions and establishes modeling practices of boundary conditions in pluvial urban flood modeling. A numerical test model within the city of Berlin is used, employing the 2D hydrodynamic finite element module of the open-source TELEMAC system. It performs unsteady simulations with nodal rainfall inputs for various precipitation scenarios, excluding infiltration. The results demonstrate that the suitability of boundary conditions is critically dependent on the surrounding topography. For boundary segments with a positive slope, a stage–discharge curve is found to outperform the other boundary conditions investigated in this study. Conversely, for segments with a negative slope, a closed wall boundary condition appears clearly preferable. Additionally, a drainage reservoir boundary condition performs effectively for more complex boundary segments but necessitates extensive preprocessing. Based on these insights, simulations were repeated with segment-tailored boundary conditions. The results indicate that this combined model outperforms the global application of each individual model. Full article

Aseptic seedlings of different ages derived from surface-sterilized mature seeds were applied as an explant source. Various explants such as 7- and 21-day-old hypocotyl fragments, 42-day-old nodal stem segments, and transverse nodal segments of stem, as well as leaf petioles, were cultured on the agar-solidified Murashige and Skoog (MS) basal medium supplemented with 0.1 mg/L IAA, 5 mg/L AgNO₃ and different types and concentrations of cytokinin (1 mg/L zeatin, 0.25 mg/L thidiazuron (TDZ), and 5 mg/L 6-benzylaminopurine (6-BAP)). Consequently, it was found that 7- and 21-day-old hypocotyl fragments, as well as nodal stem segments obtained from adult aseptic seedlings, are characterized by a high explant viability and callus formation capacity with a frequency of 79.7–100%. However, the success of in vitro somatic shoot organogenesis was significantly determined not only by the culture medium composition and explant type but also depending on its age, as well as on the size and explant preparation in cases of hypocotyl and age-matched nodal stem fragments, respectively. Multiple somatic shoot organogenesis (5.7 regenerants per explant) with a frequency of 67.5% was achieved during 3 subcultures of juvenile hypocotyl-derived callus tissue on MS culture medium containing 0.25 mg/L TDZ as cytokinin source. Castor bean regenerants were excised from the callus and successfully rooted on ½ MS basal medium without exogenous auxin (81%). In vitro plantlets with well-developed roots were adapted to ex vitro conditions with a frequency of 90%. Full article

Plasma technology, relatively new in the fields of biomedicine, agriculture, and ecology, is the subject of intensive research as a prospective means of decontamination of various microorganisms (bacteria, viruses, and fungi). The objectives of the present study were to follow the effect of cold atmospheric plasma (CAP) treatment on in vitro grown plum plants (Prunus domestica L. ‘Kyustendilska sinya’ cv.) and the possibility of eradicating or inactivating plum pox virus (PPV) causing Sharka disease by CAP. The source tree is naturally co-infected by PPV (both M and D strains). In the experiments, two different plasma sources were used. First, a surface-wave-sustained Argon plasma torch and second, an underwater diaphragm discharge. For the treatments, nodal segments (10 mm in length) from in vitro cultured plum plants with or without one leaf were prepared. Apical shoots from treated plants (PPV-positive and negative clones as well non-treated controls) were cultivated in vitro for four passages. Then they were rooted and acclimatized to ex vitro conditions, and their virus status was observed periodically for more than 3 years after treatment for the appearance of Sharka symptoms. All plants, acclimatized to ex vitro conditions, were tested for PPV by immune capture–reverse transcription–polymerase chain reaction (IC-RT-PCR). As a first step in understanding the plasma treatment of living plants, a plasma treatment variant causing no damage must be established; this has been done in our previous works. Treatment of plants by plasma with parameters that have been carefully selected leads to better development than the non-treated plants. In the treated in vitro plants, no significant differences were found in the number and length of shoots compared to the control plantlets. In ex vitro acclimated plants, greater stem length was reported, but no differences in leaf number were observed. No significant differences in growth were recorded between the control and plants that were treated twice or three times. At this stage, 3 years after ex vitro cultivation in a greenhouse, Sharka symptoms were not registered on treated in vitro negative PPV plants, and the virus was not detected by IC-RT-PCR. Very mild symptoms were showing in CAP-treated PPV-positive plants. Development of typical Sharka symptoms on non-treated controls were observed. Full article

Von Willebrand factor (VWF) is a multimer with a variable number of protomers, each of which is a head-to-head dimer of two multi-domain monomers. VWF responds to shear through the unfolding and extension of distinct domains, thereby mediating platelet adhesion and aggregation to the injured blood vessel wall. VWF's C_1-6 segment uncoils and then the A₂ domain unfolds and extends in a hierarchical and sequential manner. However, it is unclear whether there is any reservoir of further extensibility. Here, we explored the presence of cryptic extensibility in VWF by nanodissecting individual, pre-stretched multimers with atomic force microscopy (AFM). The AFM cantilever tip was pressed into the surface and moved in a direction perpendicular to the VWF axis. It was possible to pull out protein loops from VWF, which resulted in a mean contour length gain of 217 nm. In some cases, the loop became cleaved, and a gap was present along the contour. Frequently, small nodules appeared in the loops, indicating that parts of the nanodissected VWF segment remained folded. After analyzing the nodal structure, we conclude that the cryptic extensibility lies within the C_1-6 and A_1-3 regions. Cryptic extensibility may play a role in maintaining VWF’s functionality in extreme shear conditions. Full article

The damask rose (Rosa damascena Mill.) is an ornamental–medicinal plant from the Rosaceae family, and its aromatic compounds and essential oils are applied globally in the food, cosmetic, and pharmaceutical industries. Due to its economic value, this research aimed to establish a protocol for an efficient, rapid, and cost-effective method for in vitro shoot multiplication and rooting of the R. damascena ‘Kashan’ and ‘Hervy Azerbaijan’ genotypes. Nodal segments (as primary explants) were cultured on the Murashige and Skoog (MS) medium with combinations of various plant growth regulators (PGRs) such as gibberellic acid (GA₃), 6-benzylaminopurine (BAP), and indole-3-butyric acid (IBA), as well as a PGR-like substance, phloroglucinol (PG), vitamins such as ascorbic acid (AA), and activated carbon in the form of active charcoal (AC). For the establishment stage, 0.1 mg·L⁻¹ PG, 0.2 mg·L⁻¹ GA₃, and 1 mg·L⁻¹ BAP were added to the media. Secondary explants (nodal segments containing axillary buds produced from primary explants) were obtained after 30 days of in vitro culture and transferred to the proliferation media supplemented with different concentrations of BAP (0, 0.5, 1, 1.5, 2, and 2.5 mg·L⁻¹) and GA₃ (0, 0.1, 0.2, 0.4, 0.8, and 1 mg·L⁻¹) together with 0.1 mg·L⁻¹ PG and 20 mg·L⁻¹ of AA. The rooting media were augmented with different concentrations of BAP and GA₃ with 0.1 mg·L⁻¹ of IBA, PG and 20 mg·L⁻¹ of AA and AC. The results showed that the highest regeneration coefficient (4.29 and 4.28) and the largest number of leaves (23.33–24.33) were obtained in the explants grown on the medium supplemented with 2 mg·L⁻¹ BAP and 0.4 mg·L⁻¹ GA₃ for the ‘Kashan’ and ‘Hervy Azerbaijan’ genotypes, respectively. Likewise, this PGR combination provided the shortest time until bud break (approximately 6.5 days) and root emergence (approximately 10 days) in both genotypes. The highest number of shoots (4.78 per explant) and roots (3.96) was achieved in this medium in the ‘Kashan’ rose. Stem and root lengths, as well as stem and root fresh and dry weights, were also analyzed. In most measured traits, the lowest values were found in the PGRs-free control medium. Rooted plantlets were transferred to pots filled with perlite and peat moss in a 2:1 proportion and were acclimatized to ambient greenhouse conditions with a mean 90.12% survival rate. This research contributes significantly to our understanding of Damask rose propagation and has practical implications for the cosmetic and ornamental plant industries. By offering insights into the manipulation of regeneration processes, our study opens up new possibilities for the effective production of high-quality plant material. Full article

The Stevia rebaudiana Germplasm Bank at the University of Cordoba, Colombia, plays a pivotal role in conserving and efficiently utilizing the genetic variability of this species. Despite safeguarding promising genotypes with valuable traits, such as late flowering or a significant diterpenoid glycoside content, there is a need for an efficient mass propagation protocol for elite genotypes. This study aims to develop efficient in vitro micropropagation protocols for three elite S. rebaudiana genotypes (L020, L102, and Morita II). The methods employed various combinations of cytokinins and auxins following organogenesis protocols. The results showed that optimal shoot multiplication (17.3 shoots per explant) for L020 was achieved when cultures were grown on a basal medium MS supplemented with 1 μM 6-benzylaminopurine (BAP). For L102, optimal shoot multiplication (18.5 shoots per explant) was achieved in MS supplemented with 1 μM BAP and 0.5 μM naphthalene acetic acid (NAA), while for Morita II, the best treatment was an MS supplemented with 2 μM BAP and 0.5 μM NAA, producing 16.4 shoots per explant. This study successfully achieved micropropagation for promising S. rebaudiana genotypes, highlighting the significant impact of genotype on tissue culture, particularly in shoot multiplication. Developing a successful micropropagation system is crucial for the conservation and improvement of S. rebaudiana, with significant implications for its future use and performance. Full article

Plants’ genetic improvement continues to be crucial for modern agriculture, while biotechnology can offer efficient tools that enhance the selection and recommendation processes of elite clones. This work established a suitable methodology for the regeneration of blueberry (Vaccinium corymbsum) plants in cultures with colchicine. This could be considered a basis for producing populations for the selection of clones following a genetic improvement program assisted by biotechnology. The factors studied were: (a) explant type (leaf discs; nodal segments); (b) colchicine concentration (0, 0.5, 1, and 2 mg/L); and (c) time of exposure to colchicine (1, 2, 3, 5, and 30 days). The basal medium McCown’s Woody Plant (WP) supplemented with 2 mg/L 2iP and 1 mg/L BAP was used with the commercial genotype Duke as a model. A total of 1957 blueberry clones were produced in a medium with 1 mg/L colchicine, distributed at different exposure times. Flow cytometry analyses revealed the following patterns: single patterns for random samples of control plants (Duke donor) and some clones regenerated on colchicine; double patterns for chlorotic plants regenerated on colchicine. Triple and quadruple patterns were observed in callus tissues that did not regenerate plants on colchicine. Populations of plants regenerated in colchicine (6787) and control plants regenerated in in vitro culture without colchicine were adapted under greenhouse conditions. The variables evaluated at this stage were adaptability, height, diameter, number of leaves, incidence of diseases, flowering capacity, and agrobotanical traits. Selected clones demonstrating phenotypic variability (157 clones) were transplanted to field conditions. From the clonal field trial conducted under minimum tillage conditions, 38 clones were selected for improved traits related to the agricultural yield and nutritional quality of the fruits. Of these, six clones showed the highest agronomic performance and adaptability to adverse environmental conditions compared to the Duke donor genotype. It is recommended that these clones continue genotype × environment interaction trials at different locations. Full article

Industrial hemp Cannabis sativa L. is an economically important crop mostly grown for its fiber, oil, and seeds. Due to its increasing applications in the pharmaceutical industry and a lack of knowledge of gene functions in cannabinoid biosynthesis pathways, developing an efficient transformation platform for the genetic engineering of industrial hemp has become necessary to enable functional genomic and industrial application studies. A critical step in the development of Agrobacterium tumefaciens-mediated transformation in the hemp genus is the establishment of optimal conditions for T-DNA gene delivery into different explants from which whole plantlets can be regenerated. As a first step in the development of a successful Agrobacterium tumefaciens-mediated transformation method for hemp gene editing, the factors influencing the successful T-DNA integration and expression (as measured by transient β-glucuronidase (GUS) and Green Florescent Protein (GFP) expression) were investigated. In this study, the parameters for an agroinfiltration system in hemp, which applies to the stable transformation method, were optimized. In the present study, we tested different explants, such as 1- to 3-week-old leaves, cotyledons, hypocotyls, root segments, nodal parts, and 2- to 3-week-old leaf-derived calli. We observed that the 3-week-old leaves were the best explant for transient gene expression. Fully expanded 2- to 3-week-old leaf explants, in combination with 30 min of immersion time, 60 µM silver nitrate, 0.5 µM calcium chloride, 150 µM natural phenolic compound acetosyringone, and a bacterial density of OD_600nm = 0.4 resulted in the highest GUS and GFP expression. The improved method of genetic transformation established in the present study will be useful for the introduction of foreign genes of interest, using the latest technologies such as genome editing, and studying gene functions that regulate secondary metabolites in hemp. Full article