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1.
Biosystems ; 237: 105138, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38340977

RESUMO

Pancreatic ß-cells are equipped with the molecular machinery allowing them to respond to high glucose levels in the form of electrical activity and Ca2+ oscillations. These oscillations drive insulin secretion. Two key ionic mechanisms involved in this response are the Store-Operated Current and the current through ATP-dependent K+ channels. Both currents have been shown to be regulated by the protein STIM1, but this dual regulation by STIM1 has not been studied before. In this paper, we use mathematical modelling to gain insight into the role of STIM1 in the ß-cell response. We extended a previous ß-cell model to include the dynamics of STIM1 and described the dependence of the ATP-dependent K+ current on STIM1. Our simulations suggest that the total concentration of STIM1 modifies the bursting frequency, the burst duration and the intracellular Ca2+ levels. These results are in good agreement with experimental reports, and the contribution of the studied currents to electrical activity and Ca2+ dynamics is discussed. The model predicts that in the absence of STIM1 the excitability of the plasma membrane increases and that the glucose threshold for electrical activity is shifted to lower concentrations. These computational predictions may be related to impaired insulin secretion under conditions of reduced STIM1 in the diabetic state.


Assuntos
Células Secretoras de Insulina , Molécula 1 de Interação Estromal , Trifosfato de Adenosina/metabolismo , Cálcio/metabolismo , Sinalização do Cálcio , Membrana Celular/metabolismo , Glucose/metabolismo , Secreção de Insulina , Células Secretoras de Insulina/metabolismo , Molécula 1 de Interação Estromal/metabolismo , Humanos
2.
Virus Res ; 339: 199276, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38006786

RESUMO

Breeders have made important efforts to develop genotypes able to resist virus attacks in sweetpotato, a major crop providing food security and poverty alleviation to smallholder farmers in many regions of Sub-Saharan Africa, Asia and Latin America. However, a lack of accurate objective quantitative methods for this selection target in sweetpotato prevents a consistent and extensive assessment of large breeding populations. In this study, an approach to characterize and classify resistance in sweetpotato was established by assessing total yield loss and virus load after the infection of the three most common viruses (SPFMV, SPCSV, SPLCV). Twelve sweetpotato genotypes with contrasting reactions to virus infection were grown in the field under three different treatments: pre-infected by the three viruses, un-infected and protected from re-infection, and un-infected but exposed to natural infection. Virus loads were assessed using ELISA, (RT-)qPCR, and loop-mediated isothermal amplification (LAMP) methods, and also through multispectral reflectance and canopy temperature collected using an unmanned aerial vehicle. Total yield reduction compared to control and the arithmetic sum of (RT-)qPCR relative expression ratios were used to classify genotypes into four categories: resistant, tolerant, susceptible, and sensitives. Using 14 remote sensing predictors, machine learning algorithms were trained to classify all plots under the said categories. The study found that remotely sensed predictors were effective in discriminating the different virus response categories. The results suggest that using machine learning and remotely sensed data, further complemented by fast and sensitive LAMP assays to confirm results of predicted classifications could be used as a high throughput approach to support virus resistance phenotyping in sweetpotato breeding.


Assuntos
Ipomoea batatas , Potyvirus , Viroses , Ipomoea batatas/genética , Doenças das Plantas/genética , Melhoramento Vegetal , Potyvirus/genética
3.
Theor Appl Genet ; 137(1): 12, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38112758

RESUMO

Root and tuber crop breeding is at the front and center of CIP's science program, which seeks to develop and disseminate sustainable agri-food technologies, information and practices to serve objectives including poverty alleviation, income generation, food security and the sustainable use of natural resources. CIP was established in 1971 in Peru, which is part of potato's center of origin and diversity, with an initial mandate on potato and expanding to include sweetpotato in 1986. Potato and sweetpotato are among the top 10 most consumed food staples globally and provide some of the most affordable sources of energy and vital nutrients. Sweetpotato plays a key role in securing food for many households in Africa and South Asia, while potato is important worldwide. Both crops grow in a range of conditions with relatively few inputs and simple agronomic techniques. Potato is adapted to the cooler environments, while sweetpotato grows well in hot climates, and hence, the two crops complement each other. Germplasm enhancement (pre-breeding), the development of new varieties and building capacity for breeding and variety testing in changing climates with emphasis on adaptation, resistance, nutritional quality and resource-use efficiency are CIP's central activities with significant benefits to the poor. Investments in potato and sweetpotato breeding and allied disciplines at CIP have resulted in the release of many varieties some of which have had documented impact in the release countries. Partnership with diverse types of organizations has been key to the centers way of working toward improving livelihoods through crop production in the global South.


Assuntos
Solanum tuberosum , Melhoramento Vegetal/métodos , Tubérculos , Produtos Agrícolas/genética , África
4.
Euphytica ; 219(10): 110, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37780031

RESUMO

Heterosis-exploiting breeding schemes are currently under consideration as a means of accelerating genetic gains in sweetpotato (Ipomoea batatas) breeding. This study was aimed at establishing heterotic gains, fitness costs and transgressive segregation associated with sweetpotato weevil (SPW) resistance in a partial diallel cross of sweetpotato. A total of 1896 clones were tested at two sites, for two seasons each in Uganda. Data on weevil severity (WED), weevil incidence (WI), storage root yield (SRY) and dry matter content (DM) were obtained. Best linear unbiased predictors (BLUPs) for each clone across environments were used to estimate heterotic gains and for regression analyses to establish relationships between key traits. In general, low mid-parent heterotic gains were detected with the highest favorable levels recorded for SRY (14.7%) and WED (- 7.9%). About 25% of the crosses exhibited desirable and significant mid-parent heterosis for weevil resistance. Over 16% of the clones displayed superior transgressive segregation, with the highest percentages recorded for SRY (21%) and WED (18%). A yield penalty of 10% was observed to be associated with SPW resistance whereas no decline in DM was detected in relation to the same. Chances of improving sweetpotato through exploiting heterosis in controlled crosses using parents of mostly similar background are somewhat minimal, as revealed by the low heterotic gains. The yield penalty detected due to SPW resistance suggests that a trade-off may be necessary between maximizing yields and developing weevil-resistant cultivars if the current needs for this crop are to be met in weevil-prone areas.

5.
Smart Agric Technol ; 5: None, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37800125

RESUMO

The sweetpotato breeding process involves assessing different phenotypic traits, such as the sensory attributes, to decide which varieties to progress to the next stage during the breeding cycle. Sensory attributes like appearance, taste, colour and mealiness are important for consumer acceptability and adoption of new varieties. Therefore, measuring these sensory attributes is critical to inform the selection of varieties during breeding. Current methods using a trained human panel enable screening of different sweetpotato sensory attributes. Despite this, such methods are costly and time-consuming, leading to low throughput, which remains the biggest challenge for breeders. In this paper, we describe an approach to apply machine learning techniques with image-based analysis to predict flesh-colour and mealiness sweetpotato sensory attributes. The developed models can be used as high-throughput methods to augment existing approaches for the evaluation of flesh-colour and mealiness for different sweetpotato varieties. The work involved capturing images of boiled sweetpotato cross-sections using the DigiEye imaging system, data pre-processing for background elimination and feature extraction to develop machine learning models to predict the flesh-colour and mealiness sensory attributes of different sweetpotato varieties. For flesh-colour the trained Linear Regression and Random Forest Regression models attained R2 values of 0.92 and 0.87, respectively, against the ground truth values given by a human sensory panel. In contrast, the Random Forest Regressor and Gradient Boosting model attained R2 values of 0.85 and 0.80, respectively, for the prediction of mealiness. The performance of the models matched the desirable R2 threshold of 0.80 for acceptable comparability to the human sensory panel showing that this approach can be used for the prediction of these attributes with high accuracy. The machine learning models were deployed and tested by the sweetpotato breeding team at the International Potato Center in Uganda. This solution can automate and increase throughput for analysing flesh-colour and mealiness sweetpotato sensory attributes. Using machine learning tools for analysis can inform and quicken the selection of promising varieties that can be progressed for participatory evaluation during breeding cycles and potentially lead to increased chances of adoption of the varieties by consumers.

6.
Diagnostics (Basel) ; 13(9)2023 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-37175033

RESUMO

In children born with cleft lip and palate, the timing of the secondary alveolar bone graft (SABG) is crucial to its success; this involves estimating the eruption of the permanent maxillary canine. Altered dental eruption in this patient group gives impetus to the identification of dental developmental factors concerning maxillary canine eruption, which may steer the clinical decision of SABG timing. Records of over nine hundred patients who received SABG with pre- and post-operative cone beam computed tomography (CBCT) scans were analyzed for inclusion and divided into two groups (erupting or non-erupting canine after SABG). Roots of the maxillary canines and premolars were segmented from the cementoenamel junction then linear and volumetric measurements were performed. The pre- and post-operative root length and volume differences were calculated and compared statistically using independent sample tests and paired t-tests. No statistically significant differences were found in the volume change (%), or reciprocal of mean root length in the erupted and unerupted groups in the canine, first premolar, or second premolar roots except for an association between the post-operative dental root length of the canine and the maxillary canine eruption status. Therefore, assessment of root development from pre-treatment CBCT scans was not deemed worthy from a diagnostic perspective.

7.
Front Plant Sci ; 14: 1105079, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37008496

RESUMO

Crop breeding programs have often focused on the release of new varieties that target yield improvement to achieve food security and reduce poverty. While continued investments in this objective are justified, there is a need for breeding programs to be increasingly more demand-driven and responsive to the changing customer preferences and population dynamics. This paper analyses the responsiveness of global potato and sweetpotato breeding programs pursued by the International Potato Center (CIP) and its partners to three major development indicators: poverty, malnutrition and gender. The study followed a seed product market segmentation blueprint developed by the Excellence in Breeding platform (EiB) to identify, describe, and estimate the sizes of the market segments at subregional levels. We then estimated the potential poverty and nutrition impacts of investments in the respective market segments. Further, we employed the G+ tools involving multidisciplinary workshops to evaluate the gender-responsiveness of the breeding programs. Our analysis reveals that future investments in breeding programs will achieve greater impacts by developing varieties for market segments and pipelines that have more poor rural people, high stunting rates among children, anemia prevalence among women of reproductive age, and where there is high vitamin A deficiency. In addition, breeding strategies that reduce gender inequality and enhance appropriate change of gender roles (hence gender transformative) are also required.

8.
Food Secur ; 15(2): 479-491, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36570637

RESUMO

Malnutrition continues to affect many vulnerable populations worldwide, with the majority of these residing in developing and underdeveloped countries. This problem has been exacerbated by the changing climate and more recently by the COVID-19 pandemic. Urgent efforts geared towards enhancing sustainable production and value chains of nutritious foods to ensure access to healthier diets are therefore critical. A recent partnership between the World Food Programme and the International Potato Center to enhance utilization of biofortified crops in fragile environments in Kenya is a step in this direction, aimed at improving the diets of households at risk of hunger and malnutrition. This study sets out to provide early evidence on the potential impacts of the interventions spearheaded in this partnership, together with lessons for further scaling efforts. Using household level data, the study adopts an impact evaluation framework to understand the effect of nutrition awareness through the dissemination of information on Vitamin A deficiency, on the utilization of orange fleshed sweetpotato, a biofortified crop rich in Vitamin A. Results show positive and significant effects of nutrition awareness on utilization of the orange-fleshed sweetpotato. Several factors were also identified as key to determining the exposure to nutrition awareness, including proximity to markets and extension agents, gender, and education levels. For widespread and inclusive adoption and utilization of orange-fleshed sweetpotato, out-scaling efforts need to consider these determinants in designing interventions aimed at raising nutrition awareness, as a key entry point to enhancing utilization of orange-fleshed sweetpotato.

9.
Arq. ciências saúde UNIPAR ; 26(3): 1053-1067, set-dez. 2022.
Artigo em Português | LILACS | ID: biblio-1414345

RESUMO

feridas correspondem a interrupção da continuidade da pele, com a perda de uma ou mais camadas do tecido cutâneo. Curativos tradicionalmente aplicados em feridas cutâneas buscam principalmente fornecer uma barreira de proteção e permitir o desenvolvimento dos eventos celulares e bioquímicos que compreendem a cicatrização. Objetivou-se com este estudo apresentar sob a forma de revisão de literatura narrativa os principais eventos relacionados ao processo de reparo tecidual da pele, bem como abordar a aplicabilidade da técnica de eletrofiação no desenvolvimento de curativos funcionais biocompatíveis. Foram selecionados artigos voltados à caracterização dos eventos chave ocorridos a nível tecidual durante a cicatrização e, na sequência, buscou-se artigos voltados à produção, caracterização e aplicação de filmes nanoeletrofiados com ênfase na utilização de biopolímeros e substâncias bioativas. Observou-se que a maioria dos trabalhos recentes, voltados a pesquisa de base, descrevem a resposta vascular como o principal evento do processo cicatricial, sendo responsável pelas etapas que se desenrolam a seguir, que compreendem as fases inflamatória, proliferativa e de remodelamento, classicamente já descritas. Os curativos funcionais baseados em polímeros eletrofiados apresentam resultados superiores quanto testados in vitro e in vivo. As características morfoestruturais mimetizam a matriz extracelular e podem atuar em tecidos alvo como dispositivos de entrega de substâncias. Conclui-se que a atualização e reorganização de conceitos relativos à cicatrização podem contribuir no desenvolvimento de inovações, como os curativos produzidos por eletrofiação. Embora promissora, as desvantagens da técnica encontram-se principalmente no processo de obtenção e disponibilidade, que limitam a aplicação clínica em escala comercial.


Wounds correspond to the interruption of skin continuity, with the loss of one or more layers of skin tissue. Dressings traditionally applied to cutaneous wounds mainly seek to provide a protective barrier and allow the development of cellular and biochemical events that comprise healing. The objective of this study was to present, in the form of a narrative literature review, the main events related to the skin tissue repair process, as well as to address the applicability of the electrospinning technique in the development of biocompatible functional dressings. Articles focused on the characterization of the key events that occurred at the tissue level during healing were selected and, subsequently, articles focused on the production, characterization and application of nanoelectrospun films with emphasis on the use of biopolymers and bioactive substances were sought. It was observed that most recent works, focused on basic research, describe the vascular response as the main event of the healing process, being responsible for the steps that follow, which include the inflammatory, proliferative and remodeling phases, classically already described. Functional dressings based on electrospun polymers show superior results when tested in vitro and in vivo. The morphostructural features mimic the extracellular matrix and can act in target tissues as substance delivery devices. It is concluded that the updating and reorganization of concepts related to healing can contribute to the development of innovations, such as dressings produced by electrospinning. Although promising, the technique's disadvantages lie mainly in the process of obtaining and availability, which limit clinical application on a commercial scale.


Las heridas corresponden a la interrupción de la continuidad de la piel, con la pérdida de una o más capas de tejido cutáneo. Los apósitos aplicados tradicionalmente a las heridas cutáneas buscan principalmente proporcionar una barrera protectora y permitir el desarrollo de los eventos celulares y bioquímicos que comprenden la curación. El objetivo de este estudio fue presentar en forma de revisión bibliográfica narrativa los principales acontecimientos relacionados con el proceso de reparación tisular de la piel, así como abordar la aplicabilidad de la técnica de electrodeposición en el desarrollo de apósitos funcionales biocompatibles. Se seleccionaron artículos dirigidos a la caracterización de los eventos chave ocurridos a nivel técnico durante la cicatrización y, a continuación, se buscaron artículos dirigidos a la producción, caracterización y aplicación de películas nanoelectrofíricas con énfasis en el uso de biopolímeros y sustancias bioativas. Se observa que la mayoría de los trabajos recientes, realizados en la investigación de base, describen la respuesta vascular como el principal evento del proceso cicatricial, siendo responsable de las etapas que se desarrollan a continuación, que comprenden las fases inflamatoria, proliferativa y de remodelación, clásicamente descritas. Los apósitos funcionales basados en polímeros electro-tejidos presentan resultados superiores cuando se prueban in vitro e in vivo. Las características morfoestruturales mimetizan la matriz extracelular y pueden actuar en tejidos alvos como dispositivos de entrega de sustancias. Se concluye que la actualización y la reorganización de los conceptos relativos a la cicatrización pueden contribuir al desarrollo de innovaciones, como las curativas producidas por la electrofagia. Aunque es prometedora, las desventajas de la técnica radican principalmente en el proceso de obtención y la disponibilidad, que limitan la aplicación clínica a escala comercial.


Assuntos
Polímeros/uso terapêutico , Bandagens , Cicatrização , Ferimentos e Lesões/tratamento farmacológico , Plantas Medicinais/química , Biopolímeros/uso terapêutico , Literatura de Revisão como Assunto , Nanofibras/uso terapêutico
10.
Front Plant Sci ; 13: 956936, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36160986

RESUMO

Efficient breeding and selection of superior genotypes requires a comprehensive understanding of the genetics of traits. This study was aimed at establishing the general combining ability (GCA), specific combining ability (SCA), and heritability of sweetpotato weevil (Cylas spp.) resistance, storage root yield, and dry matter content in a sweetpotato multi-parental breeding population. A population of 1,896 F1 clones obtained from an 8 × 8 North Carolina II design cross was evaluated with its parents in the field at two sweetpotato weevil hotspots in Uganda, using an augmented row-column design. Clone roots were further evaluated in three rounds of a no-choice feeding laboratory bioassay. Significant GCA effects for parents and SCA effects for families were observed for most traits and all variance components were highly significant (p ≤ 0.001). Narrow-sense heritability estimates for weevil severity, storage root yield, and dry matter content were 0.35, 0.36, and 0.45, respectively. Parental genotypes with superior GCA for weevil resistance included "Mugande," NASPOT 5, "Dimbuka-bukulula," and "Wagabolige." On the other hand, families that displayed the highest levels of resistance to weevils included "Wagabolige" × NASPOT 10 O, NASPOT 5 × "Dimbuka-bukulula," "Mugande" × "Dimbuka-bukulula," and NASPOT 11 × NASPOT 7. The moderate levels of narrow-sense heritability observed for the traits, coupled with the significant GCA and SCA effects, suggest that there is potential for their improvement through conventional breeding via hybridization and progeny selection and advancement. Although selection for weevil resistance may, to some extent, be challenging for breeders, efforts could be boosted through applying genomics-assisted breeding. Superior parents and families identified through this study could be deployed in further research involving the genetic improvement of these traits.

11.
Front Plant Sci ; 13: 793904, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35557716

RESUMO

Sweetpotato is a highly heterozygous hybrid, and populations of orange-fleshed sweetpotato (OFSP) have a considerable importance for food security and health. The objectives were to estimate heterosis increments and response to selection in three OFSP hybrid populations (H1) developed in Peru for different product profiles after one reciprocal recurrent selection cycle, namely, H1 for wide adaptation and earliness (O-WAE), H1 for no sweetness after cooking (O-NSSP), and H1 for high iron (O-HIFE). The H1 populations were evaluated at two contrasting locations together with parents, foundation (parents in H0), and two widely adapted checks. Additionally, O-WAE was tested under two environmental conditions of 90-day and a normal 120-day harvest. In each H1, the yield and selected quality traits were recorded. The data were analyzed using linear mixed models. The storage root yield traits exhibited population average heterosis increments of up to 43.5%. The quality traits examined have exhibited no heterosis increments that are worth exploiting. The storage root yield genetic gain relative to the foundation was remarkable: 118.8% for H1-O-WAE for early harvest time, 81.5% for H1-O-WAE for normal harvest time, 132.4% for H1-O-NSSP, and 97.1% for H1-O-HIFE. Population hybrid breeding is a tool to achieve large genetic gains in sweetpotato yield via more efficient population improvement and allows a rapid dissemination of globally true seed that is generated from reproducible elite crosses, thus, avoiding costly and time-consuming virus cleaning of elite clones typically transferred as vegetative plantlets. The population hybrid breeding approach is probably applicable to other clonally propagated crops, where potential for true seed production exists.

13.
Front Plant Sci ; 13: 808597, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35317017

RESUMO

Crop breeding programs must accelerate crop improvement, spur widespread adoption of new varieties and increase variety turnover they are to meet the diverse needs of their clients. More comprehensive quantitative approaches are needed to better inform breeding programs about the preferred traits among farmers and other actors. However, the ability of current breeding programs to meet the demands of their clients is limited by the lack of insights about value chain actor preference for individual or packages of traits. Ranking traits based on monetary incentives, rather than subjective values, represents a more comprehensive, consistent, and quantitative approach to inform breeding programs. We conducted a large pilot in Uganda to assess the implementation of a novel approach to trait ranking, using a uniquely large sample of diverse sweetpotato value chain actors. We found meaningful differences in trait ranking and heterogeneity among different actors using this approach. We also show our approach's effectiveness at uncovering unmet demand for root quality traits and at characterizing the substantial trait demand heterogeneity among value chain players. Implementing this approach more broadly for sweetpotato and other crops would increase the effectiveness of breeding programs to improve food security in developing countries.

14.
Contemp Clin Trials ; 115: 106732, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35301133

RESUMO

Data monitoring committees (DMCs) play a critical role in protecting the safety of participants and integrity of clinical studies. While there are well-established DMC guidelines for traditional, randomized controlled trials, the clinical trial community is still in the search for best practices in data and safety monitoring in pragmatic clinical trials. ADAPTABLE was a large, open label, pragmatic, randomized controlled trial, harnessing real world data from multiple sources and studying the comparative effectiveness of the two most common dosages of aspirin in patients with atherosclerotic cardiovascular disease. Specific issues arose in ADAPTABLE such as data quality, information latency, and protocol adherence, and these issues were both expected and unexpected features of the pragmatic study design. These issues imposed great challenges to the DMC members who were tasked to make critical decisions during the study. This article summarizes the unique experience of the ADAPTABLE DMC, including the internal debates and concerns, the concerted efforts to accomplish its mission, and the special contribution of the patient representatives. We also offer recommendations on data and safety monitoring for future pragmatic trials.


Assuntos
Aterosclerose , Comitês de Monitoramento de Dados de Ensaios Clínicos , Aspirina/efeitos adversos , Confiabilidade dos Dados , Humanos , Projetos de Pesquisa
15.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 4408-4411, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34892197

RESUMO

Glucagon, the main hormone responsible for increasing blood glucose levels, is secreted by pancreatic alphacells in a Ca2+ dependent process associated to membrane potential oscillations developed by the dynamic operation of K+, Na+ and Ca2+ channels. The mechanisms behind membrane potential and Ca2+ oscillations in alpha-cells are still under debate, and some new research works have used alpha-cell models to describe electrical activity. In this paper we studied the dynamics of electrical activity of three alpha-cell models using the Lead Potential Analysis method and Bifurcation Diagrams. Our aim is to highlight the differences in their dynamic behavior and therefore, in their response to glucose. Both issues are relevant to understand the stimulus-secretion coupling in alpha-cells and then, the mechanisms behind their dysregulation in Type 2 Diabetes.Clinical Relevance - A reliable description of the electrophysiological mechanisms in pancreatic alpha-cells is key to understand and treat the dysregulation of these cells in patients with Type 2 Diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Células Secretoras de Glucagon , Cálcio , Glucagon , Humanos , Potenciais da Membrana
16.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 4412-4415, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34892198

RESUMO

One remarkable dynamic cell structure is the region between the endoplasmic reticulum (ER) and the mitochondria, termed the mitochondria-associated membranes (MAM). MAMs carry out different cellular functions such as Ca2+ homeostasis and lipid synthesis, which depend on an adequate distance separating the ER and mitochondria. A decreased distance has been observed in Alzheimer's disease, Parkinson's disease, and during cancer treatment. It is unclear how dysregulation of the spatial characteristics of MAMs can cause abnormal Ca2+ dynamics which could end in cell death. In this work, a computational model was proposed to study the relationship between a decreased ER-mitochondria distance and mitochondria-induced cell death. Our results point towards the mitochondrial permeability transition pore (mPTP) as a key cell death signaling mechanism indirectly regulated by the spatial characteristics of MAMs.Clinical Relevance- The endoplasmic reticulum-mitochondria crosstalk plays an important role in the mPTP-induced apoptosis. This process could be behind neurodegeneration in Alzheimer's and Parkinson's diseases, as well as behind the induced cell death during cancer treatment.


Assuntos
Doença de Alzheimer , Neoplasias , Doença de Parkinson , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Retículo Endoplasmático/metabolismo , Humanos , Mitocôndrias , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Doença de Parkinson/tratamento farmacológico
17.
Artigo em Inglês | MEDLINE | ID: mdl-33992583

RESUMO

OBJECTIVE: The aims of this pilot investigation were to calculate the levels of sensitivity and specificity of salivary glands ultrasonography (SGUS) in diagnosing Sjögren syndrome (SS) and to assess the ultrasonographic findings of parotid and submandibular glands. STUDY DESIGN: Patients diagnosed with SS or dry mouth and healthy controls were enrolled. Bilateral parotid and submandibular glands were assessed for (1) parenchymal inhomogeneity (PIH), (2) median size of the glands, (3) visibility of glandular posterior borders, and (4) size of sialolith, if present. RESULTS: This study included 34 female patients, of whom 12 had SS (35.3%), 12 had dry mouth (35.3%), and 10 were healthy controls (29.4%). Patients with SS showed higher PIH scores in all glands with the median differences being statistically higher in the right and left parotids and left submandibular glands (P < .001, P = .012, and P < .001, respectively). SGUS, with a PIH cutoff ≥2, showed a sensitivity of 100% and a specificity of 81.6% for detecting SS. The majority of SS had invisible glandular posterior borders (P < .001). Median size of the glands and size of the sialolith did not show any statistically significant differences between groups. CONCLUSIONS: SGUS is a noninvasive imaging modality with good sensitivity and specificity that might be valuable as a diagnostic aid for SS.


Assuntos
Síndrome de Sjogren , Feminino , Humanos , Projetos Piloto , Estudos Prospectivos , Glândulas Salivares/diagnóstico por imagem , Síndrome de Sjogren/diagnóstico por imagem , Glândula Submandibular/diagnóstico por imagem , Ultrassonografia
18.
J Prosthet Dent ; 125(4): 684.e1-684.e8, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33549342

RESUMO

STATEMENT OF PROBLEM: Zirconia restorations create significant artifacts on 3D cone beam computed tomography (CBCT) imaging. Static computer-assisted implant surgery (s-CAIS) relies on the accuracy of superimposition between an intraoral surface scan and CBCT imaging. However, how the artifacts from zirconia on the tomographic image might affect the predictability of s-CAIS is unclear. PURPOSE: The purpose of this in vitro study was to evaluate the effect of zirconia crown restorations on the superimposition process for s-CAIS. MATERIAL AND METHODS: Four stone casts generated 4 groups: a control group (CG) with no crowns and 3 experimental groups with 4 (TG4), 7 (TG7), and 13 (TG13) zirconia crowns. A total of 40 CBCT scans were made for the 4 groups (n=10). All CBCTs were imported into a computer planning software program, and the casts from all 4 groups were scanned by using a high-resolution laboratory scanner. The standard tessellation language (STL) files were imported, segmented, and the 3 files superimposed for all groups. The accuracy of the superimposition was assessed, in millimeters, in 3 planes corresponding to anterior-posterior, horizontal, and vertical, as well as the overall measurement, and the results were analyzed statistically (α=.05). RESULTS: The overall analysis demonstrated statistically significant differences between all groups (P<.001), except between CG and TG4. The anterior-posterior dimension demonstrated significant differences between CG and TG7 (P<.001), CG and TG13 (P<.001), TG4 and TG7 (P=.004), and TG4 and TG13 (P=.001). For the vertical dimension analysis, significant differences were found between CG and TG7 (P=.001), CG and TG13 (P<.001), and TG4 and TG13 (P<.001). For the horizontal variable, statistically significant differences were found between CG and TG7 (P=.049), CG and TG13 (P<.001), TG4 and TG13 (P<.001), and TG7 and TG13 (P=.003). CONCLUSIONS: The accuracy of the superimposition of the images was influenced by the number of zirconia crowns, with an increased number reducing the superimposition accuracy.


Assuntos
Artefatos , Tomografia Computadorizada de Feixe Cônico , Desenho Assistido por Computador , Coroas , Imageamento Tridimensional , Zircônio
19.
J Nutr ; 150(12): 3094-3102, 2020 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-33188398

RESUMO

BACKGROUND: Sweetpotato and potato are fast-maturing staple crops and widely consumed in low- and middle-income countries. Conventional breeding to biofortify these crops with iron could improve iron intakes. To our knowledge, iron absorption from sweetpotato and potato has not been assessed. OBJECTIVE: The aim was to assess iron absorption from regular and iron-biofortified orange-fleshed sweetpotato in Malawi and yellow-fleshed potato and iron-biofortified purple-fleshed potato in Peru. METHODS: We conducted 2 randomized, multiple-meal studies in generally healthy, iron-depleted women of reproductive age. Malawian women (n = 24) received 400 g regular or biofortified sweetpotato test meals and Peruvian women (n = 35) received 500 g regular or biofortified potato test meals. Women consumed the meals at breakfast for 2 wk and were then crossed over to the other variety. We labeled the test meals with 57Fe or 58Fe and measured cumulative erythrocyte incorporation of the labels 14 d after completion of each test-meal sequence to calculate iron absorption. Iron absorption was compared by paired-sample t tests. RESULTS: The regular and biofortified orange-fleshed sweetpotato test meals contained 0.55 and 0.97 mg Fe/100 g. Geometric mean (95% CI) fractional iron absorption (FIA) was 5.82% (3.79%, 8.95%) and 6.02% (4.51%, 8.05%), respectively (P = 0.81), resulting in 1.9-fold higher total iron absorption (TIA) from biofortified sweetpotato (P < 0.001). The regular and biofortified potato test meals contained 0.33 and 0.69 mg Fe/100 g. FIA was 28.4% (23.5%, 34.2%) from the regular yellow-fleshed and 13.3% (10.6%, 16.6%) from the biofortified purple-fleshed potato meals, respectively (P < 0.001), resulting in no significant difference in TIA (P = 0.88). CONCLUSIONS: FIA from regular yellow-fleshed potato was remarkably high, at 28%. Iron absorbed from both potato test meals covered 33% of the daily absorbed iron requirement for women of reproductive age, while the biofortified orange-fleshed sweetpotato test meal covered 18% of this requirement. High polyphenol concentrations were likely the major inhibitors of iron absorption. These trials were registered at www.clinicaltrials.gov as NCT03840031 (Malawi) and NCT04216030 (Peru).


Assuntos
Biofortificação , Ipomoea batatas/metabolismo , Ferro/administração & dosagem , Solanum tuberosum/metabolismo , Adulto , Transporte Biológico , Dieta , Feminino , Análise de Alimentos , Alimentos Fortificados , Humanos , Ipomoea batatas/química , Ferro/química , Ferro/metabolismo , Malaui , Peru , Solanum tuberosum/química , Adulto Jovem
20.
Theor Appl Genet ; 133(12): 3345-3363, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32876753

RESUMO

KEY MESSAGE: Polypoid crop breeders can balance resources between density and sequencing depth, dosage information and fewer highly informative SNPs recommended, non-additive models and QTL advantages on prediction dependent on trait architecture. The autopolyploid nature of potato and sweetpotato ensures a wide range of meiotic configurations and linkage phases leading to complex gene-action and pose problems in genotype data quality and genomic selection analyses. We used a 315-progeny biparental F1 population of hexaploid sweetpotato and a diversity panel of 380 tetraploid potato, genotyped using different platforms to answer the following questions: (i) do polyploid crop breeders need to invest more for additional sequencing depth? (ii) how many markers are required to make selection decisions? (iii) does considering non-additive genetic effects improve predictive ability (PA)? (iv) does considering dosage or quantitative trait loci (QTL) offer significant improvement to PA? Our results show that only a small number of highly informative single nucleotide polymorphisms (SNPs; ≤ 1000) are adequate for prediction in the type of populations we analyzed. We also show that considering dosage information and models considering only additive effects had the best PA for most traits, while the comparative advantage of considering non-additive genetic effects and including known QTL in the predictive model depended on trait architecture. We conclude that genomic selection can help accelerate the rate of genetic gains in potato and sweetpotato. However, application of genomic selection should be considered as part of optimizing the entire breeding program. Additionally, since the predictions in the current study are based on single populations, further studies on the effects of haplotype structure and inheritance on PA should be studied in actual multi-generation breeding populations.


Assuntos
Produtos Agrícolas/genética , Genótipo , Ipomoea batatas/genética , Melhoramento Vegetal , Polimorfismo de Nucleotídeo Único , Poliploidia , Seleção Genética , Produtos Agrícolas/crescimento & desenvolvimento , Ipomoea batatas/crescimento & desenvolvimento , Fenótipo , Locos de Características Quantitativas , Análise de Sequência de DNA
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