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1.
Cancer Immunol Immunother ; 73(11): 229, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39249543

RESUMEN

Immune checkpoint inhibitors are approved for recurrent/metastatic head and neck squamous cell carcinoma (HNSCC) but the response rate is only 13-18%. For an effective antitumor immune response, trafficking of immune cells to the tumor microenvironment (TME) is essential. We aimed to better understand immune cell migration as well as the involved chemokines in HNSCC. A transwell assay was used to study immune cell migration toward TME-conditioned medium. While T cell migration was not observed, conventional dendritic cell (cDC) migration was induced by TME-conditioned media. cDC migration correlated with various proteins in the TME secretome. CCL8, CXCL5, CCL13 and CCL7 were tested in validation experiments and addition of these chemokines induced cDC migration. Using single cell RNA-sequencing, we observed expression of CCL8, CXCL5, CCL13 and CCL7 in cancer-associated fibroblasts (CAFs). Depleting fibroblasts led to reduced cDC migration. Thus CAFs, while often seen as suppressors of antitumor immunity, play a role in attracting cDCs toward the head and neck cancer TME, which might be crucial for effective antitumor immunity and response to therapies. Indeed, we found RNA expression signatures of the indicated chemokines, cDC and CAF subpopulations, to be significantly higher in baseline tumor specimen of patients with a major pathological response to pre-surgical anti-PD-1 treatment compared to non-responding patients.


Asunto(s)
Movimiento Celular , Células Dendríticas , Neoplasias de Cabeza y Cuello , Microambiente Tumoral , Humanos , Neoplasias de Cabeza y Cuello/inmunología , Neoplasias de Cabeza y Cuello/metabolismo , Neoplasias de Cabeza y Cuello/patología , Microambiente Tumoral/inmunología , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Secretoma/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello/inmunología , Carcinoma de Células Escamosas de Cabeza y Cuello/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Fibroblastos Asociados al Cáncer/metabolismo , Fibroblastos Asociados al Cáncer/inmunología , Quimiocinas/metabolismo
2.
BMC Plant Biol ; 24(1): 416, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38760676

RESUMEN

BACKGROUND: Phytophthora root rot, a major constraint in chile pepper production worldwide, is caused by the soil-borne oomycete, Phytophthora capsici. This study aimed to detect significant regions in the Capsicum genome linked to Phytophthora root rot resistance using a panel consisting of 157 Capsicum spp. genotypes. Multi-locus genome wide association study (GWAS) was conducted using single nucleotide polymorphism (SNP) markers derived from genotyping-by-sequencing (GBS). Individual plants were separately inoculated with P. capsici isolates, 'PWB-185', 'PWB-186', and '6347', at the 4-8 leaf stage and were scored for disease symptoms up to 14-days post-inoculation. Disease scores were used to calculate disease parameters including disease severity index percentage, percent of resistant plants, area under disease progress curve, and estimated marginal means for each genotype. RESULTS: Most of the genotypes displayed root rot symptoms, whereas five accessions were completely resistant to all the isolates and displayed no symptoms of infection. A total of 55,117 SNP markers derived from GBS were used to perform multi-locus GWAS which identified 330 significant SNP markers associated with disease resistance. Of these, 56 SNP markers distributed across all the 12 chromosomes were common across the isolates, indicating association with more durable resistance. Candidate genes including nucleotide-binding site leucine-rich repeat (NBS-LRR), systemic acquired resistance (SAR8.2), and receptor-like kinase (RLKs), were identified within 0.5 Mb of the associated markers. CONCLUSIONS: Results will be used to improve resistance to Phytophthora root rot in chile pepper by the development of Kompetitive allele-specific markers (KASP®) for marker validation, genomewide selection, and marker-assisted breeding.


Asunto(s)
Capsicum , Resistencia a la Enfermedad , Estudio de Asociación del Genoma Completo , Phytophthora , Enfermedades de las Plantas , Raíces de Plantas , Polimorfismo de Nucleótido Simple , Phytophthora/fisiología , Phytophthora/patogenicidad , Capsicum/genética , Capsicum/microbiología , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/genética , Resistencia a la Enfermedad/genética , Raíces de Plantas/microbiología , Raíces de Plantas/genética , Genotipo
3.
Phytopathology ; 113(10): 1959-1966, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37246966

RESUMEN

Phytophthora capsici is one of the most devastating pathogens facing pepper (Capsicum annuum) producers worldwide. Numerous factors, such as the race of the pathogen, the growing environment, and the source of resistance, have resulted in an overall lack of widely applicable molecular markers associated with resistance. Our objective was to determine the effect of the rating system on quantitative trait locus (QTL) detection and understand inheritance patterns of host resistance that can influence selection and molecular marker accuracy. We evaluated an F2:11 recombinant inbred line population screened against the highly virulent strain (Pc134) and scored using two widely used methods, developed by Bosland and Lindsey and by Black. The rating system developed by Bosland and Lindsey resulted in slightly higher logarithm of odds for the QTL on chromosome 5, and we detected a QTL on chromosome 12 uniquely using this rating system. A QTL on chromosome 10 was detected using both rating systems, but Black resulted in considerably higher logarithm of odds for this QTL compared with the Bosland and Lindsey system. Molecular markers developed were nominally better at accurately predicting the phenotype than previously published molecular markers but did not completely explain resistance in our validation populations. The inheritance pattern of resistance in one of our F2 populations did not significantly deviate from a 7:9 segregation ratio, indicating duplicative recessive epistasis. However, these results could be confounded by the presence of incomplete gene action, which was found through the improved selection accuracy when the phenotypes of heterozygous individuals were grouped with those with susceptible alleles.


Asunto(s)
Capsicum , Phytophthora , Humanos , Sitios de Carácter Cuantitativo/genética , Capsicum/genética , Epistasis Genética , Phytophthora/genética , Enfermedades de las Plantas/genética , Resistencia a la Enfermedad/genética
4.
Phytopathology ; 113(6): 921-930, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36401843

RESUMEN

In 1922, Phytophthora capsici was described by Leon Hatching Leonian as a new pathogen infecting pepper (Capsicum annuum), with disease symptoms of root rot, stem and fruit blight, seed rot, and plant wilting and death. Extensive research has been conducted on P. capsici over the last 100 years. This review succinctly describes the salient mile markers of research on P. capsici with current perspectives on the pathogen's distribution, economic importance, epidemiology, genetics and genomics, fungicide resistance, host susceptibility, pathogenicity mechanisms, and management.


Asunto(s)
Capsicum , Fungicidas Industriales , Phytophthora , Phytophthora/genética , Enfermedades de las Plantas
5.
Memory ; 31(1): 77-91, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36131610

RESUMEN

Associative memory involves the ability to encode and remember the relationship between individual items. This ability can become diminished when there is a high degree of similarity between stimuli that are being learned. Associative memory errors often stem from the fact that lures include a high degree of item familiarity as well as mnemonic similarity with the original associative episode. The current set of experiments examined how this overlap, in the form of within-category similarity, affects veridical and false retrieval in both younger and older adults. Across three experiments, results suggest that mnemonic overlap between targets and lures is detrimental to the ability to discriminate between highly similar information. Specifically, shared category membership for targets and lures led to increased false associative memories across age groups. These results have implications for scenarios where there is a high degree of overlap between target and lure events and indicate that these types of associative memory distinctions are difficult irrespective of age.


Asunto(s)
Memoria , Reconocimiento en Psicología , Humanos , Anciano , Recuerdo Mental , Cognición , Envejecimiento
6.
J Appl Clin Med Phys ; 24(2): e13876, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36560887

RESUMEN

BACKGROUND: The clinical introduction of dedicated treatment units for online adaptive radiation therapy (OART) has led to widespread adoption of daily adaptive radiotherapy. OART allows for rapid generation of treatment plans using daily patient anatomy, potentially leading to reduction of treatment margins and increased normal tissue sparing. However, the OART workflow does not allow for measurement of patient-specific quality assurance (PSQA) during treatment delivery sessions and instead relies on secondary dose calculations for verification of adapted plans. It remains unknown if independent dose verification is a sufficient surrogate for PSQA measurements. PURPOSE: To evaluate the plan quality of previously treated adaptive plans through multiple standard PSQA measurements. METHODS: This IRB-approved retrospective study included sixteen patients previously treated with OART at our institution. PSQA measurements were performed for each patient's scheduled and adaptive plans: five adaptive plans were randomly selected to perform ion chamber measurements and two adaptive plans were randomly selected for ArcCHECK measurements. The same ArcCHECK 3D dose distribution was also sent to Mobius3D to evaluate the second-check dosimetry system. RESULTS: All (n = 96) ion chamber measurements agreed with the planned dose within 3% with a mean of 1.4% (± 0.7%). All (n = 48) plans passed ArcCHECK measurements using a 95% gamma passing threshold and 3%/2 mm criteria with a mean of 99.1% (± 0.7%). All (n = 48) plans passed Mobius3D second-check performed with 95% gamma passing threshold and 5%/3 mm criteria with a mean of 99.0% (± 0.2%). CONCLUSION: Plan measurement for PSQA may not be necessary for every online-adaptive treatment verification. We recommend the establishment of a periodic PSQA check to better understand trends in passing rates for delivered adaptive treatments.


Asunto(s)
Radioterapia de Intensidad Modulada , Humanos , Estudios Retrospectivos , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Garantía de la Calidad de Atención de Salud , Radiometría
7.
J Appl Clin Med Phys ; 24(12): e14133, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37643456

RESUMEN

PURPOSE: With the clinical implementation of kV-CBCT-based daily online-adaptive radiotherapy, the ability to monitor, quantify, and correct patient movement during adaptive sessions is paramount. With sessions lasting between 20-45 min, the ability to detect and correct for small movements without restarting the entire session is critical to the adaptive workflow and dosimetric outcome. The purpose of this study was to quantify and evaluate the correlation of observed patient movement with machine logs and a surface imaging (SI) system during adaptive radiation therapy. METHODS: Treatment machine logs and SGRT registration data log files for 1972 individual sessions were exported and analyzed. For each session, the calculated shifts from a pre-delivery position verification CBCT were extracted from the machine logs and compared to the SGRT registration data log files captured during motion monitoring. The SGRT calculated shifts were compared to the reported shifts of the machine logs for comparison for all patients and eight disease site categories. RESULTS: The average (±STD) net displacement of the SGRT shifts were 2.6 ± 3.4 mm, 2.6 ± 3.5 mm, and 3.0 ± 3.2 in the lateral, longitudinal, and vertical directions, respectively. For the treatment machine logs, the average net displacements in the lateral, longitudinal, and vertical directions were 2.7 ± 3.7 mm, 2.6 ± 3.7 mm, and 3.2 ± 3.6 mm. The average difference (Machine-SGRT) was -0.1 ± 1.8 mm, 0.2 ± 2.1 mm, and -0.5 ± 2.5 mm for the lateral, longitudinal, and vertical directions. On average, a movement of 5.8 ± 5.6 mm and 5.3 ± 4.9 mm was calculated prior to delivery for the CBCT and SGRT systems, respectively. The Pearson correlation coefficient between CBCT and SGRT shifts was r = 0.88. The mean and median difference between the treatment machine logs and SGRT log files was less than 1 mm for all sites. CONCLUSION: Surface imaging should be used to monitor and quantify patient movement during adaptive radiotherapy.


Asunto(s)
Radioterapia Guiada por Imagen , Tomografía Computarizada de Haz Cónico Espiral , Humanos , Radioterapia Guiada por Imagen/métodos , Posicionamiento del Paciente/métodos , Planificación de la Radioterapia Asistida por Computador/métodos , Movimiento , Dosificación Radioterapéutica , Tomografía Computarizada de Haz Cónico/métodos
8.
J Appl Clin Med Phys ; 24(10): e14152, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37703545

RESUMEN

PURPOSE: Knowledge-based planning (KBP) offers the ability to predict dose-volume metrics based on information extracted from previous plans, reducing plan variability and improving plan quality. As clinical integration of KBP is increasing there is a growing need for quantitative evaluation of KBP models. A .NET-based application, RapidCompare, was created for automated plan creation and analysis of Varian RapidPlan models. METHODS: RapidCompare was designed to read calculation parameters and a list of reference plans. The tool copies the reference plan field geometry and structure set, applies the RapidPlan model, optimizes the KBP plan, and generates data for quantitative evaluation of dose-volume metrics. A cohort of 85 patients, divided into training (50), testing (10), and validation (25) groups, was used to demonstrate the utility of RapidCompare. After training and tuning, the KBP model was paired with three different optimization templates to compare various planning strategies in the validation cohort. All templates used the same set of constraints for the planning target volume (PTV). For organs-at-risk, the optimization template provided constraints using the whole dose-volume histogram (DVH), fixed-dose/volume points, or generalized equivalent uniform dose (gEUD). The resulting plans from each optimization approach were compared using DVH metrics. RESULTS: RapidCompare allowed for the automated generation of 75 total plans for comparison with limited manual intervention. In comparing optimization techniques, the Dose/Volume and Lines optimization templates generated plans with similar DVH metrics, with a slight preference for the Lines technique with reductions in heart V30Gy and spinal cord max dose. The gEUD model produced high target heterogeneity. CONCLUSION: Automated evaluation allowed for the exploration of multiple optimization templates in a larger validation cohort than would have been feasible using a manual approach. A final KBP model using line optimization objectives produced the highest quality plans without human intervention.


Asunto(s)
Planificación de la Radioterapia Asistida por Computador , Radioterapia de Intensidad Modulada , Humanos , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador/métodos , Órganos en Riesgo , Radioterapia de Intensidad Modulada/métodos , Benchmarking
9.
J Appl Clin Med Phys ; 24(10): e14058, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37289550

RESUMEN

PURPOSE: To commission and assess the clinical performance of a new commercial surface imaging (SI) system by analyzing intra-fraction motion from the initial cohort of patients treated with frameless stereotactic radiosurgery (fSRS). METHODS: The IDENTIFYTM SI system was commissioned for clinical use on an Edge (Varian Medical Systems, Palo Alto, CA) linear accelerator. All patients who received intracranial radiotherapy with HyperArcTM (Varian Medical Systems, Palo Alto, CA) were immobilized with the EncompassTM (Qfix, Avondale, PA) thermoplastic mask and monitored for intra-fraction motion with SI. IDENTIFYTM log files were correlated with trajectory log files to correlate treatment parameters with SI-reported offsets. IDENTIFYTM reported offsets were correlated with gantry and couch angles to assess system performance for obstructed and clear camera field of view. Data were stratified by race to evaluate performance differences due to skin tone. RESULTS: All commissioning data were found to meet recommended tolerances. IDENTIFYTM was used to monitor intra-fraction motion on 1164 fractions from 386 patients. The median magnitude of translational SI reported offsets at the end of treatment was 0.27 mm. SI reported offsets were shown to increase when camera pods are blocked by the gantry with larger increases seen at non-zero couch angles. With camera obstruction, the median magnitude of the SI reported offset was 0.50 and 0.80 mm for White and Black patients, respectively. CONCLUSIONS: IDENTIFYTM performance during fSRS is comparable to other commercially available SI systems where offsets are shown to increase at non-zero couch angles and during camera pod blockage.


Asunto(s)
Neoplasias Encefálicas , Radiocirugia , Radioterapia de Intensidad Modulada , Humanos , Radiocirugia/métodos , Posicionamiento del Paciente/métodos , Aceleradores de Partículas , Fantasmas de Imagen , Radioterapia de Intensidad Modulada/métodos , Planificación de la Radioterapia Asistida por Computador/métodos , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/cirugía , Neoplasias Encefálicas/radioterapia
10.
J Appl Clin Med Phys ; 24(7): e13961, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36920871

RESUMEN

PURPOSE: Online Adaptive Radiation Therapy (oART) follows a different treatment paradigm than conventional radiotherapy, and because of this, the resources, implementation, and workflows needed are unique. The purpose of this report is to outline our institution's experience establishing, organizing, and implementing an oART program using the Ethos therapy system. METHODS: We include resources used, operational models utilized, program creation timelines, and our institutional experiences with the implementation and operation of an oART program. Additionally, we provide a detailed summary of our first year's clinical experience where we delivered over 1000 daily adaptive fractions. For all treatments, the different stages of online adaption, primary patient set-up, initial kV-CBCT acquisition, contouring review and edit of influencer structures, target review and edits, plan evaluation and selection, Mobius3D 2nd check and adaptive QA, 2nd kV-CBCT for positional verification, treatment delivery, and patient leaving the room, were analyzed. RESULTS: We retrospectively analyzed data from 97 patients treated from August 2021-August 2022. One thousand six hundred seventy seven individual fractions were treated and analyzed, 632(38%) were non-adaptive and 1045(62%) were adaptive. Seventy four of the 97 patients (76%) were treated with standard fractionation and 23 (24%) received stereotactic treatments. For the adaptive treatments, the generated adaptive plan was selected in 92% of treatments. On average(±std), adaptive sessions took 34.52 ± 11.42 min from start to finish. The entire adaptive process (from start of contour generation to verification CBCT), performed by the physicist (and physician on select days), was 19.84 ± 8.21 min. CONCLUSION: We present our institution's experience commissioning an oART program using the Ethos therapy system. It took us 12 months from project inception to the treatment of our first patient and 12 months to treat 1000 adaptive fractions. Retrospective analysis of delivered fractions showed that the average overall treatment time was approximately 35 min and the average time for the adaptive component of treatment was approximately 20 min.


Asunto(s)
Planificación de la Radioterapia Asistida por Computador , Tomografía Computarizada de Haz Cónico Espiral , Humanos , Estudios Retrospectivos , Fraccionamiento de la Dosis de Radiación , Dosificación Radioterapéutica
11.
Regul Toxicol Pharmacol ; 133: 105194, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35690181

RESUMEN

The deuterium kinetic isotope effect has been used to affect the cytochrome P450 metabolism of the deuterated versions of substances. This study compares the pharmacokinetics of caffeine, a Generally Recognized As Safe food and beverage ingredient, versus d9-caffeine, a potential caffeine alternative, and their respective metabolites at two dose levels in 20 healthy adults. A single dose of 50 mg or 250 mg of caffeine, or a molar-equivalent dose of d9-caffeine, were orally administered in solution with blood samples collected for up to 48 h post-dose. Plasma concentrations of parent and metabolites were analyzed using validated LC-MS/MS methods. Both d9-caffeine and caffeine were rapidly absorbed; however, d9-caffeine exhibited a higher (ca. 29%-43%) Cmax and 4-5-fold higher AUClast than caffeine, and lower Cmax, lower AUClast, and a 5-10-fold reduction in the relative exposure to the active metabolites of caffeine. Results were consistent in normal and rapid metabolizers, and both substances were well tolerated.


Asunto(s)
Cafeína , Adulto , Área Bajo la Curva , Cafeína/análogos & derivados , Cafeína/farmacocinética , Cromatografía Liquida , Estudios Cruzados , Sistema Enzimático del Citocromo P-450 , Método Doble Ciego , Voluntarios Sanos , Humanos , Espectrometría de Masas en Tándem
12.
Plant Dis ; 106(7): 1952-1958, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34941369

RESUMEN

Cultivated sweet watermelon (Citrullus lanatus) is an important vegetable crop for millions of people around the world. There are limited sources of resistance to economically important diseases within C. lanatus, whereas C. amarus has a reservoir of traits that can be exploited to improve C. lanatus for resistance to biotic and abiotic stresses. Cucurbit downy mildew (CDM), caused by Pseudoperonospora cubensis, is an emerging threat to watermelon production. We screened 122 C. amarus accessions for resistance to CDM over two tests (environments). The accessions were genotyped by whole-genome resequencing to generate 2,126,759 single nucleotide polymorphic (SNP) markers. A genome-wide association study was deployed to uncover marker-trait associations and identify candidate genes underlying resistance to CDM. Our results indicate the presence of wide phenotypic variability (1.1 to 57.8%) for leaf area infection, representing a 50.7-fold variation for CDM resistance across the C. amarus germplasm collection. Broad-sense heritability estimate was 0.55, implying the presence of moderate genetic effects for resistance to CDM. The peak SNP markers associated with resistance to P. cubensis were located on chromosomes Ca03, Ca05, Ca07, and Ca11. The significant SNP markers accounted for up to 30% of the phenotypic variation and were associated with promising candidate genes encoding leucine-rich repeat receptor-like protein kinase and the WRKY transcription factor. This information will be useful in understanding the genetic architecture of the P. cubensis-Citrullus spp. patho-system as well as development of resources for genomics-assisted breeding for resistance to CDM in watermelon.


Asunto(s)
Citrullus , Resistencia a la Enfermedad , Oomicetos , Peronospora , Enfermedades de las Plantas , Mapeo Cromosómico , Citrullus/genética , Citrullus/microbiología , Resistencia a la Enfermedad/genética , Estudios de Asociación Genética , Oomicetos/patogenicidad , Peronospora/patogenicidad , Fitomejoramiento , Enfermedades de las Plantas/microbiología , Polimorfismo de Nucleótido Simple
13.
Trop Anim Health Prod ; 54(5): 332, 2022 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-36175571

RESUMEN

Agricultural use of antimicrobials in food animal production may contribute to the global emergence of antimicrobial resistance (AMR). However, considerable gaps exist in research on the use of antimicrobial drugs (AMDs) in food animals in small-scale production systems in low- and middle-income countries, despite the minimal regulation of antimicrobials in such regions. The aim of this study was to identify factors that may influence AMD use in livestock among pastoral communities in Kenya. We collected data related to household and herd demographics, herd health, and herd management from 55 households in the Maasai Mara ecosystem, Kenya, between 2018 and 2019. We used multi-model logistic regression inference (supervised machine learning) to ascertain trends in AMD use within these households. AMD use in cattle was significantly associated with AMD use in sheep and goats (p = 0.05), implying that decisions regarding AMD use in cattle or sheep and goats were interdependent. AMD use in sheep and goats was negatively associated with vaccination against the foot and mouth disease (FMD) virus in cattle (OR = 0.06, 95% CI 0.01-0.67, p = 0.02). Less AMD use was observed for vaccine-preventable diseases like contagious ecthyma when households had access to state veterinarians (OR = 0.06, p = 0.05, 95% CI 0.004-0.96). Overall, decisions to use AMDs were associated with vaccine usage, occurrence of respiratory diseases, and access to animal health advice. This hypothesis-generating study suggests that applying community-centric methods may be necessary to understand the use of AMDs in pastoral communities.


Asunto(s)
Antiinfecciosos , Virus de la Fiebre Aftosa , Veterinarios , Animales , Antiinfecciosos/uso terapéutico , Bovinos , Ecosistema , Cabras , Humanos , Kenia/epidemiología , Ovinos
14.
Beilstein J Org Chem ; 18: 120-132, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35116082

RESUMEN

There have been several studies on the solvolysis mechanisms for alkanesulfonyl chlorides (RSO2Cl) and arenesulfonyl chlorides (ArSO2Cl). The earlier of these studies were reviewed a little over thirty years ago by Gordon, Maskill and Ruasse (Chem. Soc. Rev. 1989, 18, 123-151) in a contribution entitled "Sulfonyl Transfer Reactions". The present review will emphasize more recent contributions and, in particular, the application of the extended Grunwald-Winstein equation and kinetic solvent isotope effects to the solvolysis reactions. There is also an appreciable number of reports concerning the corresponding anhydrides with the chloride leaving group replaced by the appropriate sulfonate leaving group, concerning sulfamoyl chlorides (ZZ'NSO2Cl) with Z and Z' being alkyl or aryl and concerning the solvolysis of chlorosulfate esters (alkoxy- or aryloxysulfonyl chlorides), with the structures ROSO2Cl or ArOSO2Cl. The solvolyses of these additional types of sulfur(VI) substrates will be the topics of a future review.

15.
BMC Genomics ; 22(1): 356, 2021 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-34000992

RESUMEN

BACKGROUND: Chile peppers (Capsicum spp.) are among the most important horticultural crops in the world due to their number of uses. They are considered a major cultural and economic crop in the state of New Mexico in the United States. Evaluating genetic diversity in current New Mexican germplasm would facilitate genetic improvement for different traits. This study assessed genetic diversity, population structure, and linkage disequilibrium (LD) among 165 chile pepper genotypes using single nucleotide polymorphism (SNP) markers derived from genotyping-by-sequencing (GBS). RESULTS: A GBS approach identified 66,750 high-quality SNP markers with known map positions distributed across the 12 chromosomes of Capsicum. Principal components analysis revealed four distinct clusters based on species. Neighbor-joining phylogenetic analysis among New Mexico State University (NMSU) chile pepper cultivars showed two main clusters, where the C. annuum genotypes grouped together based on fruit or pod type. A Bayesian clustering approach for the Capsicum population inferred K = 2 as the optimal number of clusters, where the C. chinense and C. frutescens grouped in a single cluster. Analysis of molecular variance revealed majority of variation to be between the Capsicum species (76.08 %). Extensive LD decay (~ 5.59 Mb) across the whole Capsicum population was observed, demonstrating that a lower number of markers would be required for implementing genome wide association studies for different traits in New Mexican type chile peppers. Tajima's D values demonstrated positive selection, population bottleneck, and balancing selection for the New Mexico Capsicum population. Genetic diversity for the New Mexican chile peppers was relatively low, indicating the need to introduce new alleles in the breeding program to broaden the genetic base of current germplasm. CONCLUSIONS: Genetic diversity among New Mexican chile peppers was evaluated using GBS-derived SNP markers and genetic relatedness on the species level was observed. Introducing novel alleles from other breeding programs or from wild species could help increase diversity in current germplasm. We present valuable information for future association mapping and genomic selection for different traits for New Mexican chile peppers for genetic improvement through marker-assisted breeding.


Asunto(s)
Capsicum , Teorema de Bayes , Capsicum/genética , Variación Genética , Estudio de Asociación del Genoma Completo , Humanos , New Mexico , Filogenia , Fitomejoramiento , Polimorfismo de Nucleótido Simple
16.
BMC Plant Biol ; 21(1): 601, 2021 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-34922461

RESUMEN

BACKGROUND: Phytophthora root rot, caused by Phytophthora capsici, is a major disease affecting Capsicum production worldwide. A recombinant inbred line (RIL) population derived from the hybridization between 'Criollo de Morellos-334' (CM-334), a resistant landrace from Mexico, and 'Early Jalapeno', a susceptible cultivar was genotyped using genotyping-by-sequencing (GBS)-derived single nucleotide polymorphism (SNP) markers. A GBS-SNP based genetic linkage map for the RIL population was constructed. Quantitative trait loci (QTL) mapping dissected the genetic architecture of P. capsici resistance and candidate genes linked to resistance for this important disease were identified. RESULTS: Development of a genetic linkage map using 1,973 GBS-derived polymorphic SNP markers identified 12 linkage groups corresponding to the 12 chromosomes of chile pepper, with a total length of 1,277.7 cM and a marker density of 1.5 SNP/cM. The maximum gaps between consecutive SNP markers ranged between 1.9 (LG7) and 13.5 cM (LG5). Collinearity between genetic and physical positions of markers reached a maximum of 0.92 for LG8. QTL mapping identified genomic regions associated with P. capsici resistance in chromosomes P5, P8, and P9 that explained between 19.7 and 30.4% of phenotypic variation for resistance. Additive interactions between QTL in chromosomes P5 and P8 were observed. The role of chromosome P5 as major genomic region containing P. capsici resistance QTL was established. Through candidate gene analysis, biological functions associated with response to pathogen infections, regulation of cyclin-dependent protein serine/threonine kinase activity, and epigenetic mechanisms such as DNA methylation were identified. CONCLUSIONS: Results support the genetic complexity of the P. capsici-Capsicum pathosystem and the possible role of epigenetics in conferring resistance to Phytophthora root rot. Significant genomic regions and candidate genes associated with disease response and gene regulatory activity were identified which allows for a deeper understanding of the genomic landscape of Phytophthora root rot resistance in chile pepper.


Asunto(s)
Capsicum/genética , Capsicum/microbiología , Resistencia a la Enfermedad/genética , Phytophthora/fisiología , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Mapeo Cromosómico , Marcadores Genéticos , Genoma de Planta , Técnicas de Genotipaje , Raíces de Plantas/microbiología , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo
17.
Pacing Clin Electrophysiol ; 44(10): 1683-1690, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34405423

RESUMEN

BACKGROUND: Multisite LV stimulation therapy allows for stimulation of two different left ventricular pacing vectors within a single LV lead and may improve responsiveness to cardiac resynchronization therapy (CRT). This study prospectively evaluated the safety and efficacy of the MultiPole Pacing (MPP) feature in CRT non-responder patients. METHODS AND RESULTS: CRT non-responders with a standard CRT-D indication were eligible for enrollment into the MPP Sub-Study. Patient status, NYHA classification, Patient Global Assessment (PGA), and adverse events were collected at follow-up. A clinical composite score (CCS) was determined at the 6 month follow-up visit. The primary objective was defined as the proportion of patients with an improved CCS. Safety was evaluated as freedom from MPP system related adverse events requiring additional invasive intervention to resolve. A total of 53 patients were enrolled across 26 U.S. centers. The cumulative follow-up duration was 24.1 years. CCS was improved in 35.6% of patients (p < .0001 when compared to a performance goal of 3%) after 6 months of MPP therapy. When incorporating patient feedback into a modified CCS, 60.0% of patients showed an improvement. Three patients (5.7%) experienced hospitalization for heart failure, and three patient deaths occurred over the follow-up period. No MPP system-related events were reported for an AE-free rate of 100% (95% CI 93.28% to 100.0%). CONCLUSIONS: The results of this small, non-randomized study suggest that the MPP feature is safe, and may be effective at converting a percentage of CRT non-responders to responders. Larger, randomized studies are needed to confirm this result.


Asunto(s)
Terapia de Resincronización Cardíaca/métodos , Insuficiencia Cardíaca/fisiopatología , Insuficiencia Cardíaca/terapia , Ventrículos Cardíacos/fisiopatología , Anciano , Dispositivos de Terapia de Resincronización Cardíaca , Femenino , Humanos , Masculino , Estudios Prospectivos , Estados Unidos
18.
Int J Mol Sci ; 22(14)2021 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-34299023

RESUMEN

A study was carried out on the solvolysis of 1-adamantyl chlorothioformate (1-AdSCOCl, 1) in hydroxylic solvents. The rate constants of the solvolysis of 1 were well correlated using the Grunwald-Winstein equation in all of the 20 solvents (R = 0.985). The solvolyses of 1 were analyzed as the following two competing reactions: the solvolysis ionization pathway through the intermediate (1-AdSCO)+ (carboxylium ion) stabilized by the loss of chloride ions due to nucleophilic solvation and the solvolysis-decomposition pathway through the intermediate 1-Ad+Cl- ion pairs (carbocation) with the loss of carbonyl sulfide. In addition, the rate constants (kexp) for the solvolysis of 1 were separated into k1-Ad+Cl- and k1-AdSCO+Cl- through a product study and applied to the Grunwald-Winstein equation to obtain the sensitivity (m-value) to change in solvent ionizing power. For binary hydroxylic solvents, the selectivities (S) for the formation of solvolysis products were very similar to those of the 1-adamantyl derivatives discussed previously. The kinetic solvent isotope effects (KSIEs), salt effects and activation parameters for the solvolyses of 1 were also determined. These observations are compared with those previously reported for the solvolyses of 1-adamantyl chloroformate (1-AdOCOCl, 2). The reasons for change in reaction channels are discussed in terms of the gas-phase stabilities of acylium ions calculated using Gaussian 03.


Asunto(s)
Adamantano/química , Cloro/química , Iones/química , Solventes/química , Cinética , Termodinámica
19.
J Sci Food Agric ; 101(4): 1515-1522, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-32851665

RESUMEN

BACKGROUND: Edamame is a vegetable soybean (Glycine max) rich in protein with well-balanced amino acid profiles, including all the essential amino acids. It is also relatively high in oil consisting of five fatty acids. In this study, fatty and amino acid contents in oven-dried edamame and mature seeds in 54 genotypes were analyzed to help edamame breeding and relevant research. RESULTS: Significant differences (P < 0.01) between dried edamame and mature soybeans were found for all traits, suggesting that the contents of seed fatty and amino acids varied with drying method and/or growth stage. The genotypic effects were significant for amino acids in all cases and mostly for fatty acids. Fatty acid content was more variable than amino acids in both edamame and mature soybeans. The broad-sense heritability estimates of traits in mature soybeans (51.89-90.37%) were larger than those in edamame seeds (13.10-81.83%), and the estimates for amino acids were larger than those for fatty acids. Correlations between the two edamame drying methods or between the edamame and mature soybeans were significant for all fatty and amino acids with few exceptions, and the correlation coefficients for amino acids (0.36-0.89) were larger than those for fatty acids (0.29-0.81). CONCLUSIONS: Selection for both fatty and amino acids in edamame seems less effective than that in mature soybeans, and the improvement of amino acids would be more achievable than fatty acid improvement. Indirect selection through mature soybeans may benefit the edamame improvement for most of the amino acids. © 2020 Society of Chemical Industry.


Asunto(s)
Aminoácidos/química , Ácidos Grasos/química , Glycine max/química , Desecación , Manipulación de Alimentos , Genotipo , Semillas/química , Semillas/clasificación , Semillas/genética , Semillas/crecimiento & desarrollo , Glycine max/genética , Glycine max/crecimiento & desarrollo
20.
J Appl Clin Med Phys ; 21(12): 90-95, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33095971

RESUMEN

PURPOSE: To report on the use of surface guided imaging during frameless intracranial stereotactic radiotherapy with automated delivery via HyperArcTM (Varian Medical Systems, Palo Alto, CA). METHODS: All patients received intracranial radiotherapy with HyperArcTM and were monitored for intrafraction motion by the AlignRT® (VisionRT, London, UK) surface imaging (SI) system. Immobilization was with the EncompassTM (Qfix, Avondale, PA) aquaplast mask device. AlignRT® log files were correlated with trajectory log files to correlate treatment parameters with SI reported offsets. SI reported offsets were correlated with gantry angle and analyzed for performance issues at non-zero couch angles and during camera-pod blockage during gantry motion. Demographics in the treatment management system were used to identify race and determine if differences in SI reported offsets are due to skin tone settings. RESULTS: A total of 981 fractions were monitored over 14 months and 819 were analyzed. The median AlignRT® reported motion from beginning to the end of treatment was 0.24 mm. The median offset before beam on at non-zero couch angles was 0.55 mm. During gantry motion when camera pods are blocked, the median magnitude was below 1 mm. Median magnitude of offsets at non-zero couch angles was not found to be significantly different for patients stratified by race. CONCLUSIONS: Surface image guidance is a viable alternative to scheduled mid-treatment imaging for monitoring intrafraction motion during stereotactic radiosurgery with automated delivery.


Asunto(s)
Radiocirugia , Tomografía Computarizada de Haz Cónico , Humanos , Inmovilización , Movimiento (Física) , Posicionamiento del Paciente , Planificación de la Radioterapia Asistida por Computador
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