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1.
J Acoust Soc Am ; 155(2): 1308-1314, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38349807

RESUMO

Distress or alarm calls are vocalizations made when animals are in stressful situations or faced with a predator. Squirrels (Sciuridae) are known for being very vocal; however, most studies on alarm vocalizations are limited to ground squirrels. We investigated the acoustic behavior of the arboreal fox squirrel (Sciurus niger) under different conditions. Specifically, we tested the hypothesis that fox squirrels modify acoustic alarm behavior in response to different perceived threat levels and that this response is affected by sex and individual experience. Squirrels were trapped, and acoustic data were collected during periods in which the squirrels were alone, approached by humans, manipulated in traps, and handled by humans. Calls were categorized based on acoustic features, and we quantified the call rate (calls/s) across conditions. Threat level significantly affected vocal rate, with squirrels producing more calls overall when alone but shifting the proportion of emitted call types as threat level increased. Sex, capture history, and individual had no effect on call rate. These results suggest that fox squirrels use a graded alarm call response system to respond to threatening situations.


Assuntos
Sciuridae , Vocalização Animal , Animais , Humanos , Sciuridae/fisiologia , Níger , Vocalização Animal/fisiologia
2.
Dev Med Child Neurol ; 65(10): 1280-1291, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-36908077

RESUMO

AIM: This overview of Cochrane systematic reviews (CSRs) reports on current evidence on the effectiveness of rehabilitation interventions for individuals with cerebral palsy (CP) and the quality of the evidence. METHOD: Following the inclusion criteria defined by the World Health Organization, all CSRs tagged in the Cochrane Rehabilitation database that were relevant for individuals with CP were included. A mapping synthesis was used to group outcomes and comparisons of included CSRs indicating the effect of rehabilitation interventions and the certainty of evidence. RESULTS: A total of eight CSRs were included in the evidence map. The effect of interventions varied across comparisons and the certainty of evidence was inconsistent, ranging from high to very low. The best evidence was found for botulinum neurotoxin A (BoNT-A) combined with occupational therapy in the management of spasticity. However, the effect of BoNT-A on drooling and salivation remains unclear. A paucity of randomized controlled trials studying treatments for both dystonia and postural deformities was noted. INTERPRETATION: This review emphasizes the need to further investigate the effectiveness and cost-benefit of rehabilitation interventions for individuals with CP. WHAT THIS PAPER ADDS: The quality and quantity of evidence on rehabilitation interventions for cerebral palsy is limited worldwide. Botulinum neurotoxin A plus occupational therapy showed robust efficacy for the management of upper-limb spasticity. Evidence on sleep-positioning systems for hip migration and trihexyphenidyl for dystonia is scarce.


Assuntos
Toxinas Botulínicas Tipo A , Paralisia Cerebral , Distonia , Sialorreia , Humanos , Paralisia Cerebral/complicações , Toxinas Botulínicas Tipo A/uso terapêutico , Revisões Sistemáticas como Assunto
3.
J Pediatr ; 251: 17-23.e2, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36096177

RESUMO

OBJECTIVE: To determine parental preferred language, terminology, and approach after prenatal counseling for an anticipated extremely preterm delivery. STUDY DESIGN: Pregnant persons (and their partners) admitted at 220/7-256/7 weeks of estimated gestation participated in post antenatal-counseling semistructured interviews to explore preferred language and decision-making approaches of their antenatal counseling session. Interviews were audio-recorded and transcribed, and thematic analysis of the data was performed. RESULTS: Thirty-nine interviews were conducted representing 28 total prenatal consults. Analysis identified 2 overarching themes impacting the whole counseling experience: the need for reassurance and compassionate communication, while parents traveled along a dynamic decision-making journey they described as fluid and ever-changing. Related themes included the following: (1) Finding Balance: parents reported the importance of balancing positivity and negativity as well as tailoring the amount of information, (2) The Unspoken: parents described assumptions and inferences surrounding language, resuscitation options, and values that can cloud the counseling process, (3) Making the Intangible Tangible: parents reported the importance of varied communication strategies, for example, visuals to better anticipate and prepare, and (4) Team Synergism: Parents expressed desire for communication and consistency among and between teams, which increased trust. CONCLUSIONS: Parents facing extremely premature delivery generally did not report remembering specific terminology used during prenatal consultation but rather how the language and counseling approach made them feel and affected the decision-making process. These findings have implications for further research and educational intervention design to improve clinicians' counseling practices to better reflect parental preferences and ultimately improve counseling outcomes.


Assuntos
Doenças do Recém-Nascido , Doenças do Prematuro , Recém-Nascido , Feminino , Humanos , Gravidez , Comunicação , Tomada de Decisões , Empatia , Pais/psicologia , Pesquisa Qualitativa , Aconselhamento
4.
J Anat ; 236(6): 1160-1166, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32092791

RESUMO

Assessing the factors that contribute to successful locomotor performance can provide critical insight into how animals survive in challenging habitats. Locomotion is powered by muscles, so that differences in the relative proportions of red (slow-oxidative) vs. white (fast-glycolytic) fibers can have significant implications for locomotor performance. We compared the relative proportions of axial red muscle fibers between groups of juveniles of the amphidromous gobiid fish, Sicyopterus stimpsoni, from the Hawaiian Islands. Juveniles of this species migrate from the ocean into freshwater streams, navigating through a gauntlet of predators that require rapid escape responses, before reaching waterfalls which must be climbed (using a slow, inching behavior) to reach adult breeding habitats. We found that fish from Kaua'i have a smaller proportion of red fibers in their tail muscles than fish from Hawai'i, matching expectations based on the longer pre-waterfall stream reaches of Kaua'i that could increase exposure to predators, making reduction of red muscle and increases in white muscle advantageous. However, no difference in red muscle proportions was identified between fish that were either successful or unsuccessful in scaling model waterfalls during laboratory climbing trials, suggesting that proportions of red muscle are near a localized fitness peak among Hawaiian individuals.


Assuntos
Ecossistema , Peixes/anatomia & histologia , Locomoção/fisiologia , Fibras Musculares Esqueléticas/fisiologia , Músculo Esquelético/anatomia & histologia , Animais , Peixes/fisiologia , Havaí , Músculo Esquelético/fisiologia , Rios
7.
J Exp Biol ; 220(Pt 21): 3873-3877, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28883088

RESUMO

During evolutionary reinvasions of water by terrestrial vertebrates, ancestrally tubular limb bones often flatten to form flippers. Differences in skeletal loading between land and water might have facilitated such changes. In turtles, femoral shear strains are significantly lower during swimming than during walking, potentially allowing a release from loads favoring tubular shafts. However, flipper-like morphology in specialized tetrapod swimmers is most accentuated in the forelimbs. To test whether the forelimbs of turtles also experience reduced torsional loading in water, we compared strains on the humerus of river cooters (Pseudemys concinna) between swimming and terrestrial walking. We found that humeral shear strains are also lower during swimming than during terrestrial walking; however, this appears to relate to a reduction in overall strain magnitude, rather than a specific reduction in twisting. These results indicate that shear strains show similar reductions between swimming and walking for forelimb and hindlimb, but these reductions are produced through different mechanisms.


Assuntos
Evolução Biológica , Úmero/fisiologia , Natação , Tartarugas/fisiologia , Caminhada , Animais , Fenômenos Biomecânicos , Feminino , Úmero/anatomia & histologia , Masculino , Tartarugas/anatomia & histologia
8.
Biol Lett ; 13(1)2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28123109

RESUMO

Specialization for a new habitat often entails a cost to performance in the ancestral habitat. Although aquatic lifestyles are ancestral among extant cryptodiran turtles, multiple lineages, including tortoises (Testudinidae) and emydid box turtles (genus Terrapene), independently specialized for terrestrial habitats. To what extent is swimming function retained in such lineages despite terrestrial specialization? Because tortoises diverged from other turtles over 50 Ma, but box turtles did so only 5 Ma, we hypothesized that swimming kinematics for box turtles would more closely resemble those of aquatic relatives than those of tortoises. To test this prediction, we compared high-speed video of swimming Russian tortoises (Testudo horsfieldii), box turtles (Terrapene carolina) and two semi-aquatic emydid species: sliders (Trachemys scripta) and painted turtles (Chrysemys picta). We identified different kinematic patterns between limbs. In the forelimb, box turtle strokes most resemble those of tortoises; for the hindlimb, box turtles are more similar to semi-aquatic species. Such patterns indicate functional convergence of the forelimb of terrestrial species, whereas the box turtle hindlimb exhibits greater retention of ancestral swimming motions.


Assuntos
Extremidades/fisiologia , Natação , Tartarugas/fisiologia , Animais , Fenômenos Biomecânicos , Ecossistema , Filogenia , Especificidade da Espécie
9.
Paediatr Anaesth ; 27(7): 718-725, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28557286

RESUMO

BACKGROUND: Liver transplantation represents a major surgery involving a highly vascular organ. Reports defining the scope of bleeding in pediatric liver transplants are few. AIMS: We conducted a retrospective analysis of liver transplants performed at our pediatric tertiary care center to quantify blood loss, blood product utilization, and to determine predictors for massive intraoperative bleeding. METHODS: Pediatric patients who underwent isolated liver transplantation at Boston Children's Hospital between 2011 and 2016 were included. The amount of blood product transfused in the perioperative period and the incidence of postoperative complications were reported. Univariable and multivariable logistic regressions were used to determine predictors for massive bleeding, defined as estimated blood loss exceeding one circulating blood volume within 24 hours. RESULTS: Sixty-eight children underwent liver transplantation during the study period and were included in the analysis. Multivariable logistic regression analysis identified the following independent predictors of massive bleeding: preoperative hemoglobin level <8.5 g/dL (OR 11.09, 95% CI 1.87-65.76), INR >1.5 (OR 11.62, 95% CI 2.36-57.26), platelet count <100 109 /L (OR 7.92, 95% CI 1.46-43.05), and surgery duration >600 minutes (OR 6.97, 95% CI 0.99-48.92). CONCLUSIONS: Pediatric liver transplantation is associated with substantial blood loss and a significant blood product transfusion burden. A 43% incidence of massive bleeding is reported. Further efforts are needed to improve bleeding management in this high-risk population.


Assuntos
Transplante de Fígado/efeitos adversos , Hemorragia Pós-Operatória/epidemiologia , Perda Sanguínea Cirúrgica , Transfusão de Sangue/estatística & dados numéricos , Criança , Pré-Escolar , Feminino , Hemoglobinas/análise , Humanos , Incidência , Lactente , Coeficiente Internacional Normatizado , Masculino , Contagem de Plaquetas , Complicações Pós-Operatórias/epidemiologia , Valor Preditivo dos Testes , Estudos Retrospectivos , Centros de Atenção Terciária , Tromboelastografia
10.
J Perianesth Nurs ; 32(4): 352-355, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28739067

RESUMO

This article describes the distinctive function of the pediatric clinical research nurse (CRN) in the anesthesia setting. The pediatric CRN in anesthesia acts as a liaison between families and the research team and is the major nexus between the principal investigator or anesthesiologist on a study, and the collaborating surgeons from many different departments. This is unique because the CRNs collaborate with physicians in specialties that can include plastics, urology, neurosurgery, orthopaedics, otolaryngology, cardiology, critical care, and many other departments. The profession requires a breath of knowledge ranging from clinical understanding of diseases, surgical procedures, and recovery to cognitive and developmental stages, to expertise in the research protocol process. Our objective was to describe these specialized activities of the pediatric anesthesia CRN, with focus on care coordination, communication, and continuity of care. Defining this role will enhance the quality of clinical research conducted by the CRN in anesthesia and may influence the development of novel medical treatments.


Assuntos
Anestesia , Relações Interprofissionais , Papel do Profissional de Enfermagem , Pesquisa em Enfermagem , Enfermagem Pediátrica , Relações Profissional-Família , Criança , Humanos , Equipe de Assistência ao Paciente
12.
Paediatr Anaesth ; 26(10): 960-9, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27510707

RESUMO

BACKGROUND: Operative treatment of craniosynostosis is associated with substantial blood loss, often requiring transfusion of packed red blood cells (PRBC) and coagulation products. AIMS: The aim of this prospective study was to analyze thromboelastographic (TEG) parameters and platelet fibrinogen product to determine predictors of substantial blood loss, and the need for PRBC transfusion and coagulation products. METHODS: With IRB approval, we enrolled 120 children undergoing craniosynostosis repair with a standardized anesthetic, fluid management, and TEG measurements at predefined times. Outcomes of interest were intraoperative blood loss, and need for PRBC transfusion and coagulation products. Multivariable logistic regression and receiver operating characteristic (ROC) curve analysis was applied to determine independent predictors of substantial blood loss and need for coagulation products. RESULTS: One hundred and eighteen children were included in the analysis. Forty-four required PRBC transfusion (median 26 ml·kg(-1) ; IQR: 22-42) with median blood loss of 56 ml·kg(-1) (IQR: 43-83). Factors associated with the PRBC transfusion included type of surgery, duration of surgery, and three TEG parameters, α-angle, MA, and K-time (all P < 0.001). A predictive algorithm was developed by subgroup analysis of cranial vault reconstruction (CVR) patients for substantial intraoperative blood loss (defined as ≥60 ml·kg(-1) ) and need for coagulation products with ROC-derived cut-off values: platelet fibrinogen product, <343; α-angle, <62°; MA, <55 mm; K-time, >2.1 min. The best prognostic combination included at least two of these four predictors (sensitivity 89%, specificity 90%). Multivariable regression identified MA as the only independent predictor of coagulation product administration (P < 0.001) and ROC analysis identified MA <46 mm as the optimal cut-off (sensitivity 86%, specificity 94%). CONCLUSIONS: Risk for substantial intraoperative blood loss can be assessed using TEG parameters and platelet fibrinogen product, whereas the need for coagulation products is strongly related to low MA. Patients susceptible to substantial blood loss can be risk stratified based on their TEG/platelet fibrinogen product profile.


Assuntos
Perda Sanguínea Cirúrgica/estatística & dados numéricos , Transfusão de Sangue/estatística & dados numéricos , Craniossinostoses , Fibrinogênio/análise , Tromboelastografia/métodos , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Estudos Prospectivos , Medição de Risco , Sensibilidade e Especificidade
13.
Anesthesiology ; 122(5): 1021-32, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25692276

RESUMO

BACKGROUND: Craniosynostosis surgery is associated with clinically significant postoperative events requiring intensive care unit (ICU) admission. The authors investigate specific variables, which might influence the risk for these events, and thereby make recommendations regarding the need for postoperative ICU admission. METHODS: A retrospective review of 225 children undergoing open craniosynostosis repair at a single center during a 10-yr period is reported. The primary outcome measure was the incidence of predefined clinically relevant postoperative cardiorespiratory and hematological events requiring ICU admission. RESULTS: The incidences of postoperative cardiorespiratory and hematological events requiring ICU care were 14.7% (95% CI, 10.5 to 20.1%) and 29.7% (95% CI, 24.0 to 36.3%), respectively. Independent predictors of cardiorespiratory events were body weight less than 10 kg, American Society of Anesthesiologists physical status 3 or 4, intraoperative transfusion of greater than 60 ml/kg packed erythrocytes, and the occurrence of an intraoperative complication. The independent predictors of hematological events were body weight less than 10 kg, American Society of Anesthesiologists physical status 3 or 4, intraoperative transfusion of greater than 60 ml/kg packed erythrocytes, transfusion of hemostatic products (fresh-frozen plasma, platelets, and/or cryoprecipitate), and tranexamic acid not administered. CONCLUSIONS: Children undergoing craniosynostosis surgery are at increased risk for clinically significant postoperative events requiring ICU admission if they are less than 10 kg body weight, American Society of Anesthesiologists physical status 3 or 4, require intraoperative transfusion of greater than 60 ml/kg of packed erythrocytes, receive hemostatic blood products, or if they develop a significant intraoperative complication. Tranexamic acid administration was associated with fewer postoperative events. A predictive clinical algorithm for pediatric patients having major craniosynostosis surgery was developed and validated to risk stratify these patients.


Assuntos
Craniossinostoses/cirurgia , Procedimentos Neurocirúrgicos/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Manuseio das Vias Aéreas/efeitos adversos , Manuseio das Vias Aéreas/métodos , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Lactente , Unidades de Terapia Intensiva , Complicações Intraoperatórias/epidemiologia , Complicações Intraoperatórias/terapia , Masculino , Complicações Pós-Operatórias/terapia , Hemorragia Pós-Operatória/epidemiologia , Hemorragia Pós-Operatória/terapia , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
14.
Biol Lett ; 11(6): 20150110, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26085496

RESUMO

Members of several terrestrial vertebrate lineages have returned to nearly exclusive use of aquatic habitats. These transitions were often accompanied by changes in skeletal morphology, such as flattening of limb bone shafts. Such morphological changes might be correlated with the exposure of limb bones to altered loading. Though the environmental forces acting on the skeleton differ substantially between water and land, no empirical data exist to quantify the impact of such differences on the skeleton, either in terms of load magnitude or regime. To test how locomotor loads change between water and land, we compared in vivo strains from femora of turtles (Trachemys scripta) during swimming and terrestrial walking. As expected, strain magnitudes were much lower (by 67.9%) during swimming than during walking. However, the loading regime of the femur also changed between environments: torsional strains are high during walking, but torsion is largely eliminated during swimming. Changes in loading regime between environments may have enabled evolutionary shifts to hydrodynamically advantageous flattened limb bones in highly aquatic species. Although circular cross sections are optimal for resisting torsional loads, the removal of torsion would reduce the advantage of tubular shapes, facilitating the evolution of flattened limbs.


Assuntos
Fêmur/fisiologia , Natação , Tartarugas/fisiologia , Caminhada , Animais , Evolução Biológica , Fenômenos Biomecânicos , Feminino , Masculino , Tartarugas/anatomia & histologia
15.
Theor Appl Genet ; 127(10): 2159-71, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25159608

RESUMO

KEY MESSAGE: Generation of a dense SNP-based linkage map of a diploid potato population and identification of major QTLs for tuber shape and eye depth on chromosomes 2 and 10. This paper reports the construction of a genetic map of a highly heterozygous full-sib diploid potato population (06H1) based on the use of a set of 8,303 single nucleotide polymorphism (SNP) markers. The map contains 1,355 distinct loci and 2,157 SNPs, 802 of which co-segregate with other markers. We find high levels of collinearity between the 12 chromosomal maps with a recently improved version of the potato genome assembly, with the expected genetic clustering in centromeric regions. The linkage maps are used in combination with highly detailed phenotypic assessments conducted over two growing seasons to perform quantitative trait loci analysis of two important potato traits, tuber shape and eye depth. The major loci segregating for tuber shape in 06H1 map to loci on chromosomes 2 and 10, with smaller effects mapping to three other chromosomes. A major locus for tuber eye depth co-locates with the tuber shape locus on chromosome 10. To assess when tuber shape is established in the developing tuber, we have performed staged observations of tuber formation. Our observations suggest that tuber shape is determined very early in tuber development.


Assuntos
Tubérculos/anatomia & histologia , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Solanum tuberosum/genética , Mapeamento Cromossômico , Cromossomos de Plantas , Diploide , Ligação Genética , Genoma de Planta , Genótipo , Tubérculos/genética
16.
J Cardiothorac Surg ; 19(1): 168, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566159

RESUMO

Cardiac leiomyosarcomas are a rare subset of the already infrequent, primary malignant cardiac neoplasia spectrum. The most common site for a primary leiomyosarcoma of the ventricle is on the right with fewer than five globally reported cases in the left ventricle. Most present with non-specific symptoms but attention is usually sought after the appearance of compressive symptoms or arrhythmias. We present a case of a left ventricular leiomyosarcoma in a 50-year old female patient that had a delayed diagnosis and its subsequent surgical resection and oncological management with docetaxel and gemcitabine. This case highlights the need for a high index of suspicion for cardiac masses especially if there are competing chronic diseases with similar symptomatology. Given the rare presentation of left ventricular leiomyosarcomas, case reports may provide valuable information that is otherwise unavailable.


Assuntos
Neoplasias Cardíacas , Leiomiossarcoma , Feminino , Humanos , Pessoa de Meia-Idade , Ventrículos do Coração/patologia , Leiomiossarcoma/diagnóstico , Leiomiossarcoma/cirurgia , Leiomiossarcoma/patologia , Neoplasias Cardíacas/diagnóstico , Neoplasias Cardíacas/cirurgia , Neoplasias Cardíacas/patologia
17.
BMJ Open ; 14(2): e080529, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38320840

RESUMO

INTRODUCTION: Rapid genomic sequencing (rGS) in critically ill infants with suspected genetic disorders has high diagnostic and clinical utility. However, rGS has primarily been available at large referral centres with the resources and expertise to offer state-of-the-art genomic care. Critically ill infants from racial and ethnic minority and/or low-income populations disproportionately receive care in safety-net and/or community settings lacking access to state-of-the-art genomic care, contributing to unacceptable health equity gaps. VIrtual GenOme CenteR is a 'proof-of-concept' implementation science study of an innovative delivery model for genomic care in safety-net neonatal intensive care units (NICUs). METHODS AND ANALYSIS: We developed a virtual genome centre at a referral centre to remotely support safety-net NICU sites predominantly serving racial and ethnic minority and/or low-income populations and have limited to no access to rGS. Neonatal providers at each site receive basic education about genomic medicine from the study team and identify eligible infants. The study team enrols eligible infants (goal n of 250) and their parents and follows families for 12 months. Enrolled infants receive rGS, the study team creates clinical interpretive reports to guide neonatal providers on interpreting results, and neonatal providers return results to families. Data is collected via (1) medical record abstraction, (2) surveys, interviews and focus groups with neonatal providers and (3) surveys and interviews with families. We aim to examine comprehensive implementation outcomes based on the Proctor Implementation Framework using a mixed methods approach. ETHICS AND DISSEMINATION: This study is approved by the institutional review board of Boston Children's Hospital (IRB-P00040496) and participating sites. Participating families are required to provide electronic written informed consent and neonatal provider consent is implied through the completion of surveys. The results will be disseminated via peer-reviewed publications and data will be made accessible per National Institutes of Health (NIH) policies. TRIAL REGISTRATION NUMBER: NCT05205356/clinicaltrials.gov.


Assuntos
Etnicidade , Unidades de Terapia Intensiva Neonatal , Recém-Nascido , Lactente , Criança , Humanos , Estado Terminal , Grupos Minoritários , Genômica
18.
Integr Comp Biol ; 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37312281

RESUMO

Recent strides toward improving diversity, equity, and inclusion (DEI) in field biology present a unique opportunity for transdisciplinary exploration of the impacts and state of a topic that has remained hereto largely underexplored and under-discussed in the academic setting. Within current literature, themes of racial and gender inequity, power imbalances, unsafe environments, and underdeveloped infrastructure and resources are widespread. Thus, we organized a symposium that addressed these compelling issues in field biology DEI through a multitude of experiential and academic lenses. This article will orient the reader to the special issue and offer summative goals and outcomes of the symposium that can provide tangible steps toward creating meaningful improvements in the state of DEI and safety in field settings.

19.
Food Energy Secur ; 12(1): e377, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37035023

RESUMO

Previously, we developed and applied a glasshouse screen for potato tuber yield under heat stress and identified a candidate gene (HSc70) for heat tolerance by genetic analysis of a diploid potato population. Specific allelic variants were expressed at high levels on exposure to moderately elevated temperature due to variations in gene promoter sequence. In this study, we aimed to confirm the results from the glasshouse screen in field trials conducted over several seasons and locations including those in Kenya, Malawi and the UK. We extend our understanding of the HSc70 gene and demonstrate that expression level of HSc70 correlates with tolerance to heat stress in a wide range of wild potato relatives. The physiological basis of the protective effect of HSc70 was explored and we show that genotypes carrying the highly expressed HSc70 A2 allele are protected against photooxidative damage to PSII induced by abiotic stresses. Overall, we show the potential of HSc70 alleles for breeding resilient potato genotypes for multiple environments.

20.
Hortic Res ; 10(11): uhad211, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38023472

RESUMO

Potato is the third most important food crop in the world. Diverse pathogens threaten sustainable crop production but can be controlled, in many cases, through the deployment of disease resistance genes belonging to the family of nucleotide-binding, leucine-rich-repeat (NLR) genes. To identify effective disease resistance genes in established varieties, we have successfully established SMRT-AgRenSeq in tetraploid potatoes and have further enhanced the methodology by including dRenSeq in an approach that we term SMR-AgRenSeq-d. The inclusion of dRenSeq enables the filtering of candidates after the association analysis by establishing a presence/absence matrix across resistant and susceptible varieties that is translated into an F1 score. Using a SMRT-RenSeq-based sequence representation of the NLRome from the cultivar Innovator, SMRT-AgRenSeq-d analyses reliably identified the late blight resistance benchmark genes Rpi-R1, Rpi-R2-like, Rpi-R3a, and Rpi-R3b in a panel of 117 varieties with variable phenotype penetrations. All benchmark genes were identified with an F1 score of 1, which indicates absolute linkage in the panel. This method also identified nine strong candidates for Gpa5 that controls the potato cyst nematode (PCN) species Globodera pallida (pathotypes Pa2/3). Assuming that NLRs are involved in controlling many types of resistances, SMRT-AgRenSeq-d can readily be applied to diverse crops and pathogen systems.

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