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1.
Ultrasound Med Biol ; 50(10): 1515-1521, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39085001

RESUMEN

OBJECTIVES: To develop and validate a prediction model utilizing clinical and ultrasound (US) data for preoperative assessment of efficacy following US-guided thermal ablation (TA) in patients with benign thyroid nodules (BTNs) ≥ 2 cm. MATERIALS AND METHODS: We retrospectively assessed 962 patients with 1011 BTNs who underwent TA at four tertiary centers between May 2018 and July 2022. Ablation efficacy was categorized into therapeutic success (volume reduction rate [VRR] > 50%) and non-therapeutic success (VRR ≤ 50%). We identified independent factors influencing the ablation efficacy of BTNs ≥ 2 cm in the training set using multivariate logistic regression. On this basis, a prediction model was established. The performance of model was further evaluated by discrimination (area under the curve [AUC]) in the validation set. RESULTS: Of the 1011 nodules included, 952 (94.2%) achieved therapeutic success at the 12-month follow-up after TA. Independent factors influencing VRR > 50% included sex, nodular composition, calcification, volume, and largest diameter (all p < 0.05). The prediction equation was established as follows: p = 1/1 + Exp∑[8.113 -2.720 × (if predominantly solid) -2.790 × (if solid) -1.275 × (if 10 mL < volume ≤ 30mL) -1.743 × (if volume > 30 mL) -1.268 × (if with calcification) -2.859 × (if largest diameter > 3 cm) +1.143 × (if female)]. This model showed great discrimination, with AUC of 0.908 (95% confidence interval [CI]: 0.868-0.947) and 0.850 (95% CI: 0.748-0.952) in the training and validation sets, respectively. CONCLUSIONS: A clinical prediction model was successfully developed to preoperatively predict the therapeutic success of BTNs larger than 2 cm in size following US-guided TA. This model aids physicians in evaluating treatment efficacy and devising personalized prognostic plans.


Asunto(s)
Nódulo Tiroideo , Humanos , Nódulo Tiroideo/diagnóstico por imagen , Nódulo Tiroideo/cirugía , Femenino , Estudios Retrospectivos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Adulto , Técnicas de Ablación/métodos , Anciano , Ultrasonografía Intervencional/métodos
2.
Neurooncol Adv ; 5(1): vdad117, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37841695

RESUMEN

Background: The development of new therapies for malignant gliomas has been stagnant for decades. Through the promising outcomes in clinical trials of oncolytic virotherapy, there is now a glimmer of hope in addressing this situation. To further enhance the antitumor immune response of oncolytic viruses, we have equipped a modified oncolytic adenovirus (oAds) with a recombinant interferon-like gene (YSCH-01) and conducted a comprehensive evaluation of the safety and efficacy of this modification compared to existing treatments. Methods: To assess the safety of YSCH-01, we administered the oAds intracranially to Syrian hamsters, which are susceptible to adenovirus. The efficacy of YSCH-01 in targeting glioma was evaluated through in vitro and in vivo experiments utilizing various human glioma cell lines. Furthermore, we employed a patient-derived xenograft model of recurrent glioblastoma to test the effectiveness of YSCH-01 against temozolomide. Results: By modifying the E1A and adding survivin promoter, the oAds have demonstrated remarkable safety and an impressive ability to selectively target tumor cells. In animal models, YSCH-01 exhibited potent therapeutic efficacy, particularly in terms of its distant effects. Additionally, YSCH-01 remains effective in inhibiting the recurrent GBM patient-derived xenograft model. Conclusions: Our initial findings confirm that a double-modified oncolytic adenovirus armed with a recombinant interferon-like gene is both safe and effective in the treatment of malignant glioma. Furthermore, when utilized in combination with a targeted therapy gene strategy, these oAds exhibit a more profound effect in tumor therapy and an enhanced ability to inhibit tumor growth at remote sites.

3.
Diagnostics (Basel) ; 13(18)2023 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-37761299

RESUMEN

BACKGROUND: Rural general practitioners (GPs) have insufficient diagnostic information to deal with complex clinical scenarios due to the inequality in medical imaging resources in rural and remote communities. The objective of this study is to explore the value of a tele-mentored handheld ultrasound (tele-HHUS) system, allowing GPs to provide ultrasound (US) services in rural and remote communities. METHODS: Overall, 708 patients underwent tele-HHUS examination between March and October 2021 and March and April 2022 across thirteen primary hospitals and two tertiary-care general hospitals. All US examinations were guided and supervised remotely in real time by US experts more than 300 km away using the tele-HHUS system. The following details were recorded: location of tele-HHUS scanning, primary complaints, clinical diagnosis, and US findings. The recommendations (referral or follow-up) based on clinical experience alone were compared with those based on clinical experience with tele-HHUS information. RESULTS: Tele-HHUS examinations were performed both in hospital settings (90.6%, 642/708) and out of hospital settings (9.4%, 66/708). Leaving aside routine physical examinations, flank pain (14.2%, 91/642) was the most common complaint in inpatients, while chest distress (12.1%, 8/66) and flank discomfort (12.1%, 8/66) were the most common complaints in out-of-hospital settings. Additionally, the referral rate increased from 5.9% to 8.3% (kappa = 0.202; p = 0.000). CONCLUSIONS: The tele-HHUS system can help rural GPs perform HHUS successfully in remote and rural communities. This novel mobile telemedicine model is valuable in resource-limited areas.

4.
BMC Plant Biol ; 23(1): 287, 2023 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-37248451

RESUMEN

BACKGROUND: Assessment of segregating populations for their ability to withstand drought stress conditions is one of the best approaches to develop breeding lines and drought tolerant varieties. Bambara groundnut (Vigna subterranea L. Verdc.) is a leguminous crop, capable of growing in low-input agricultural systems in semi-arid areas. An F4 bi-parental segregating population obtained from S19-3 × DodR was developed to evaluate the effect of drought stress on photosynthetic parameters and identify QTLs associated with these traits under drought-stressed and well-watered conditions in a rainout shelter. RESULTS: Stomatal conductance (gs), photosynthesis rate (A), transpiration rate (E) and intracellular CO2 (Ci) were significantly reduced (p < 0.05) while water use efficiency (WUE) was significantly increased (p < 0.05) under drought-stressed conditions. A strong linear correlation was observed between gs, WUE, A, E and Ci under both water regimes. The variability between different water treatment, among individual lines and the interaction between lines and environment for photosynthetic parameters provides resources for superior lines selection and drought resistant variety improvement. Significant QTL for gs and FV/FM under well-watered conditions were mapped on LG5 and LG3, respectively, with more than 20% of the PVE, which could be considered as the major QTL to control these traits. Five clustered QTLs for photosynthetic traits under drought-stressed and well-watered conditions were mapped on LG5, LG6A, LG10 and LG11, respectively. CONCLUSIONS: Significant and putative QTLs associated with photosynthetic parameters and the effect of drought stress on these traits have been revealed by QTL linkage mapping and field experiment in the F4 segregating population derived from S19-3 × DodR in bambara groundnut. The study provides fundamental knowledge of how photosynthetic traits response to drought stress and how genetic features control these traits under drought-stressed and well-watered conditions in bambara groundnut.


Asunto(s)
Vigna , Vigna/genética , Sequías , Fitomejoramiento , Mapeo Cromosómico , Fotosíntesis/genética
5.
Acad Radiol ; 30(11): 2647-2656, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36966072

RESUMEN

RATIONALE AND OBJECTIVES: To compare the clinical and economic effects of ultrasound (US)-guided radiofrequency ablation (RFA) with parathyroidectomy (PTX) for primary hyperparathyroidism (PHPT). MATERIALS AND METHODS: From April 2014 to April 2021, 123 PHPT patients who received US-guided RFA or PTX were studied. Propensity score (PS) matching was used to balance the baseline data of the two groups. The rates of cure, recurrent and persistent PHPT, and complications were compared. A Chinese healthcare system perspective cost minimization analysis was conducted. RESULTS: After PS matching, 37 patient pairs (1:1) were created for the two groups. Follow-up was 27.2 ± 10.6 months and 28.8 ± 16.1 months for the RFA and PTX groups, respectively. At the last follow-up, there was no evidence of differences regarding clinical cure rate between the two groups (RFA vs. PTX, 91.9% vs. 94.6%, p = 1.000). Recurrent PHPT did not develop in any patient. One patient in each group had persistent PHPT. The incidence of complications and side effects, except postoperative pain (RFA vs. PTX, 16.2% vs. 40.5%, p = 0.020), were no significant difference between the two groups (all, p > 0.05). The incremental cost was -$284.00; thus, RFA was more cost-effective. For patients with employee medical insurance or resident medical insurance, the incremental costs (RFA vs. PTX) were -$391.94 and -$49.43, respectively. CONCLUSION: There were no significant differences in efficacy and safety between RFA and PTX. As the incremental cost for RFA compared with PTX was negative, RFA may be used as a more cost-effective nonsurgical treatment alternative for PHPT.

6.
Front Public Health ; 10: 915071, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35923952

RESUMEN

Background: Disability has become a global population health challenge. Due to difficulties in self-care or independent living, patients with disability mainly live in community-based care centers or institutions for long-term care. Nonetheless, these settings often lack basic medical resources, such as ultrasonography. Thus, remote ultrasonic robot technology for clinical applications across wide regions is imperative. To date, few experiences of remote diagnostic systems in rural care centers have been reported. Objective: To assess the feasibility of a fifth-generation cellular technology (5G)-based robot-assisted remote ultrasound system in a care center for disabled patients in rural China. Methods: Patients underwent remote robot-assisted and bedside ultrasound examinations of the liver, gallbladder, spleen, and kidneys. We compared the diagnostic consistency and differences between the two modalities and evaluated the examination duration, image quality, and safety. Results: Forty-nine patients were included (21 men; mean age: 61.0 ± 19.0 [range: 19-91] years). Thirty-nine and ten had positive and negative results, respectively; 67 lesions were detected. Comparing the methods, 41 and 8 patients had consistent and inconsistent diagnoses, respectively. The McNemar and kappa values were 0.727 and 0.601, respectively. The mean duration of remote and bedside examinations was 12.2 ± 4.5 (range: 5-26) min and 7.5 ± 1.8 (range: 5-13) min (p < 0.001), respectively. The median image score for original images on the patient side and transmitted images on the doctor side was 5 points (interquartile range: [IQR]: 4.7-5.0) and 4.7 points (IQR: 4.5-5.0) (p = 0.176), respectively. No obvious complications from the examination were reported. Conclusions: A 5G-based robot-assisted remote ultrasound system is feasible and has comparable diagnostic efficiency to traditional bedside ultrasound. This system may provide a unique solution for basic ultrasound diagnostic services in primary healthcare settings.


Asunto(s)
Personas con Discapacidad , Robótica , Adulto , Anciano , Anciano de 80 o más Años , China , Humanos , Masculino , Persona de Mediana Edad , Robótica/métodos , Población Rural , Ultrasonografía/métodos
7.
Korean J Radiol ; 23(5): 555-565, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35506529

RESUMEN

OBJECTIVE: To assess the efficacy and safety of ultrasound (US)-guided radiofrequency ablation (RFA) in patients with primary hyperparathyroidism (PHPT). MATERIALS AND METHODS: This prospective study enrolled 39 participants (14 male, 25 female; mean age, 59.5 ± 15.3 [range, 18-87] years) between September 1, 2018, and January 31, 2021. All participants had parathyroid lesions causing PHPT, proven biochemically and through imaging. The imaging features of the PHPT nodules, including the shape, margin, size, composition, and location, were evaluated before treatment. Serum intact parathyroid hormone, calcium, and phosphorus levels; parathyroid nodule volume; and PHPT-related symptoms were recorded before and after treatment. We calculated the technical success, biochemical cure, and clinical cure rates for these patients. Complications were evaluated during and after the ablation. RESULTS: Complete ablation was achieved in 38 of the 39 nodules in the 39 enrolled participants. All the patients were treated in one session. The technical success rate was 97.4% (38/39). The mean follow-up duration was 13.2 ± 4.6 (range, 6.0-24.9) months. At 6 and 12 months post-RFA, the biochemical cure rates were 82.1% (32/39) and 84.4% (27/32), respectively, and the clinical cure rates were 100% (39/39) and 96.9% (31/32), respectively. Only 2.6% (1/39) of the patients had recurrent PHPT. At 1, 3, 6, and 12 months after technically successful RFA, 44.7% (17/38), 34.3% (12/35), 15.8% (6/38), and 12.5% (4/32) of participants, respectively, had elevated eucalcemic parathyroid hormone levels. Recurrent laryngeal nerve paralysis occurred in 5.1% (2/39) of the patients, who recovered spontaneously within 1-3 months. CONCLUSION: US-guided RFA was effective and safe for PHPT patients. RFA may be an alternative treatment tool for patients who cannot tolerate or refuse to undergo surgery.


Asunto(s)
Hiperparatiroidismo Primario , Ablación por Radiofrecuencia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Hiperparatiroidismo Primario/diagnóstico por imagen , Hiperparatiroidismo Primario/cirugía , Masculino , Persona de Mediana Edad , Hormona Paratiroidea , Estudios Prospectivos , Ablación por Radiofrecuencia/métodos , Estudios Retrospectivos , Resultado del Tratamiento , Ultrasonografía Intervencional , Adulto Joven
8.
Front Plant Sci ; 13: 760879, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35419010

RESUMEN

Bambara groundnut [Vigna subterranea (L.) Verdc.] is grown in rainfed production systems and suffers from periodic drought stress (DS), leading to yield reductions. Natural genotypic variation for root traits is essential for adaptation to water deficit conditions. However, root traits have not been fully utilised as selection criteria to improve DS in bambara groundnut. The present study explored the natural genotypic variation found in single genotypes of bambara groundnut derived from landraces to identify adaptive differences in tap root length (TRL) and root length density (RLD) in response to DS. A diverse core collection of eight bambara groundnut genotypes from various locations (namely, Gresik, LunT, IITA-686, DodR, S19-3, Tiga nicuru, and Ankpa-4, DipC1), were grown for two seasons (2018 and 2019) in polyvinyl chloride (PVC) columns with well-watered (WW) and 30-day DS treatments. Plant samples were collected at 55 days after emergence (DAE) (30 days of DS) and at 105 DAE (30 days of DS plus 50 days of recovery). Under DS, differential TRL among genotypes at 55 DAE was observed, with DodR recording the longest among genotypes with an increase (1% in 2018) in TRL under DS compared to WW, whereas LunT and IITA-686 showed significant (p < 0.001) decrease in TRL (27 and 25%, respectively, in 2018). Average RLD was observed to have the highest reduction under DS in the 90-110 cm layer (42 and 58%, respectively, in 2018 and 2019). Rainy habitat LunT had limited roots in 2018 and recorded the least (0.06 ± 0.013 cm-3) RLD in 2019. However, dry-habitat DodR showed an increase in the RLD (60-90 cm) under DS compared to WW, while dry-habitat S19-3 densely occupied all depths with RLD of 0.16 ± 0.05 and 0.18 ± 0.01 cm cm-3 in the deepest layer in both seasons, respectively. Reduced RLD under DS showed recovery when the plants were re-watered. These plants were additionally observed to have RLD that surpasses the density in WW at all soil depths at 105 DAE. Also, recovery was shown in Tiga nicuru and DodR (0-30 cm) and IITA-686 (90-110 cm) in 2019. Average RLD under DS treatment was associated with substantial grain yield advantage (R 2 = 0.27 and R 2 = 0.49, respectively) in 2018 and 2019. An increase in TRL allowed DodR to quickly explore water at a deeper soil depth in response to gradually declining soil water availability. High RLD in genotypes such as DodR, DipC1 and S19-3 also offered adaptive advantage over other genotypes under DS. Variation in intrinsic RLD in deeper soil depths in the studied genotypes determines root foraging capacity when facing DS. This suggests that different agroecological environments to which bambara groundnut is subjected in its natural habitat have promoted a phenotypic differentiation in root systems to adapt to ecotypic conditions, which may help offset the impact of DS. The natural genotypic variation exhibited, especially by DodR, could be exploited to identify potential quantitative trait loci (QTLs) that control deep rooting and root length density.

9.
Int J Hyperthermia ; 39(1): 490-496, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35285391

RESUMEN

OBJECTIVE: To investigate the efficacy of radiofrequency ablation (RFA) as a treatment option for primary hyperparathyroidism (pHPT) and risk factors for postablative eucalcemic parathyroid hormone elevation (ePTH). METHODS: This retrospective study included 51 patients with pHPT who underwent RFA. The patients were divided into the ePTH and normal PTH groups, based on the serum intact parathyroid hormone (iPTH) level one month after ablation. Serum iPTH, calcium, and phosphorus levels, and the volume reduction rates (VRR) of the parathyroid glands were compared between the groups at each follow-up point. Risk factors for ePTH at one month after ablation were examined. RESULTS: After RFA, one (2%) patient had persistent pHPT, and 50 (98%) patients were cured. The incidence rates of ePTH at 1, 3, 6, and 12 months were 48%, 30%, 20%, and 16%, respectively. Serum iPTH levels in the ePTH group were higher than those in the normal PTH group at each follow-up point (all p < 0.05), except 1 day after ablation (p > 0.05). Serum calcium and phosphorus levels, and the VRR of the glands were comparable in both groups at each follow-up point (all p > 0.05), except for calcium levels 3 days after RFA (p < 0.05). Baseline iPTH (odds ratio, 1.067; p = 0.045) and calcium (odds ratio, 3.923; p = 0.038) levels were independent risk factors for ePTH 1 month after RFA. CONCLUSIONS: RFA is safe and effective for the treatment of pHPT. Moreover, ePTH occurrence after RFA was associated with baseline iPTH and calcium levels and did not increase the risk of recurrent pHPT.


Asunto(s)
Hiperparatiroidismo Primario , Ablación por Radiofrecuencia , Calcio , Humanos , Hiperparatiroidismo Primario/cirugía , Hormona Paratiroidea , Paratiroidectomía , Ablación por Radiofrecuencia/efectos adversos , Estudios Retrospectivos , Factores de Riesgo
10.
Int J Hyperthermia ; 38(1): 1023-1030, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34219596

RESUMEN

OBJECTIVE: To compare the clinical outcomes of microwave ablation (MWA) and radiofrequency ablation (RFA) in the treatment of primary hyperparathyroidism (pHPT). METHOD: This retrospective study included 104 pHPT patients treated by MWA or RFA between January 2015 and March 2020 in four centers. The clinical outcomes including effectiveness and complications were compared between the two groups. Ablation cure was defined as the reestablishment of normal values of serum calcium and intact parathyroid hormone (iPTH) at least more than 6 months. Clinical cure was defined as the reestablishment of normal values of serum calcium and iPTH throughout the entire follow-up period. RESULTS: A total of 77 patients underwent MWA (mean age, 55.5 ± 16.4 years) and 27 underwent RFA (mean age, 58.9 ± 15.6 years). During the follow-up (median, 18.7 months in the MWA group; 12 months in the RFA group), no difference was observed between ablation cure rates (88.3% vs. 88.9%, p = 1.000), clinical cure rates (87.0% vs. 82.3%, p = .880), recurrent pHPT (5.2% vs. 3.7%, p = .447), persistent pHPT (11.7% vs. 11.1%, p = 1.000) and complication rate (9.1% vs. 3.7%, p = .677). A maximum diameter less than 0.7 cm was an independent prognostic factor of uncured pHPT in ablation (hazard ratio, 0.1; 95% confidence interval: 0.02, 0.54; p = .007). Major complication - voice change encountered in five patients (6.5%) in the MWA group and in one patient (3.7%) in the RFA group. CONCLUSION: Both RFA and MWA are safe and effective techniques for patients with pHPT, with comparable clinical outcomes.


Asunto(s)
Ablación por Catéter , Hiperparatiroidismo Primario , Ablación por Radiofrecuencia , Adulto , Anciano , Humanos , Hiperparatiroidismo Primario/cirugía , Microondas/uso terapéutico , Persona de Mediana Edad , Hormona Paratiroidea , Estudios Retrospectivos , Resultado del Tratamiento
11.
Front Nutr ; 7: 601496, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33363196

RESUMEN

Rapid population growth, climate change, intensive monoculture farming, and resource depletion are among the challenges that threaten the increasingly vulnerable global agri-food system. Heavy reliance on a few major crops is also linked to a monotonous diet, poor dietary habits, and micronutrient deficiencies, which are often associated with diet-related diseases. Diversification-of both agricultural production systems and diet-is a practical and sustainable approach to address these challenges and to improve global food and nutritional security. This strategy is aligned with the recommendations from the EAT-Lancet report, which highlighted the urgent need for increased consumption of plant-based foods to sustain population and planetary health. Bambara groundnut (Vigna subterranea (L.) Verdc.), an underutilized African legume, has the potential to contribute to improved food and nutrition security, while providing solutions for environmental sustainability and equity in food availability and affordability. This paper discusses the potential role of Bambara groundnut in diversifying agri-food systems and contributing to enhanced dietary and planetary sustainability, with emphasis on areas that span the value chain: from genetics, agroecology, nutrition, processing, and utilization, through to its socioeconomic potential. Bambara groundnut is a sustainable, low-cost source of complex carbohydrates, plant-based protein, unsaturated fatty acids, and essential minerals (magnesium, iron, zinc, and potassium), especially for those living in arid and semi-arid regions. As a legume, Bambara groundnut fixes atmospheric nitrogen to improve soil fertility. It is resilient to adverse environmental conditions and can yield on poor soil. Despite its impressive nutritional and agroecological profile, the potential of Bambara groundnut in improving the global food system is undermined by several factors, including resource limitation, knowledge gap, social stigma, and lack of policy incentives. Multiple research efforts to address these hurdles have led to a more promising outlook for Bambara groundnut; however, there is an urgent need to continue research to realize its full potential.

12.
ACS Omega ; 5(33): 20903-20911, 2020 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-32875225

RESUMEN

A facile, cost-effective, and eco-friendly method was proposed to synthesize Fe3O4@tannic acid@Au nanocomposites (Fe3O4@TA@Au). First, Fe3O4 nanoparticles with diameters of 20 and 200 nm were synthesized by co-precipitation and solvothermal methods, respectively. Gold nanoparticles were deposited on magnetic Fe3O4 through tannic acid-metal-polymer intermediate-layer-mediated reductions. The catalytic activities of the as-prepared Fe3O4@TA@Au were investigated by spectroscopically monitoring the reduction of 4-nitrophenol (4-NP) and methylene blue (MB), which could be achieved within several minutes with an excess of NaBH4. The impact of the Fe3O4 size on the overall catalytic ability of the Fe3O4@TA@Au was systematically studied. The reaction rate constants of the Fe3O4-20 nm@TA@Au for 4-NP and MB reduction were 0.432 and 0.543 min-1, respectively. For the Fe3O4-200 nm@TA@Au nanocomposite, the optimized reaction rate constants for 4-NP and MB reduction were 3.09 and 0.441 min-1, respectively. Due to magnetic separation, the Fe3O4@TA@Au could be easily harvested and recycled. After five recycling cycles, the catalytic ability remained over 90%, and the recycling process could be completed in several minutes, highlighting its potential as a catalyst for 4-NP and MB removal.

13.
Anal Methods ; 12(33): 4166-4171, 2020 08 27.
Artículo en Inglés | MEDLINE | ID: mdl-32785298

RESUMEN

A smartphone-based analysis system is favored for point-of-care testing applications. The present work proposes a novel micro-spectroscopy/imaging system comprising a portable spectrometer as an optical sensor and a compact homemade microscope to acquire the image and spectra of micron-scale regions. Protein concentration quantification based on the bicinchoninic acid method was demonstrated with the proposed micro-spectroscopy/imaging system to analyse the spectrometer signals. Morphologies of onion endothelial and human breast cancer cells, used as biological sample models, were characterized to demonstrate the microscopic imaging capacity of the device. The ability to simultaneously obtain morphological and spectral information using the proposed portable device was demonstrated by examining the 10 µm sub-pixels of a smartphone screen. These results highlight the potential for adopting a smartphone-based micro-spectroscopy/imaging system for point-of-care testing.


Asunto(s)
Microscopía , Teléfono Inteligente , Humanos , Pruebas en el Punto de Atención , Refractometría , Análisis Espectral
14.
Plants (Basel) ; 9(5)2020 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-32438672

RESUMEN

Characterizing the morphological variability in root system architecture (RSA) during the sensitive pre-flowering growth stage is important for crop performance. To assess this variation, eight bambara groundnut single genotypes derived from landraces of contrasting geographic origin were selected for root system architecture and rooting distribution studies. Plants were grown in a polyvinyl chloride (PVC) column system under controlled water and nutrient availability in a rainout shelter. Days to 50% plant emergence was characterized during the first two weeks after sowing, while taproot length (TRL), root length (RL), root length density (RLD), branching number (BN), branching density (BD) and intensity (BI), surface area (SA), root volume (RV), root diameter (RDia), root dry weight (RDW), shoot dry weight (SDW), and shoot height (SH) were determined at the end of the experiment, i.e., 35 days after emergence. Genotypes S19-3 and DipC1 sourced from drier regions of sub-Saharan Africa generally had longer taproots and greater root length distribution in deeper (60 to 90 cm) soil depths. In contrast, bambara groundnut genotypes from wetter regions (i.e., Gresik, Lunt, and IITA-686) in Southeast Asia and West Africa exhibited relatively shallow and highly branched root growth closer to the soil surface. Genotypes at the pre-flowering growth stage showed differential root foraging patterns and branching habits with two extremes, i.e., deep-cheap rooting in the genotypes sourced from dry regions and a shallow-costly rooting system in genotypes adapted to higher rainfall areas with shallow soils. We propose specific bambara groundnut genotype as donors in root trait driven breeding programs to improve water capture and use efficiency.

15.
Micromachines (Basel) ; 10(12)2019 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-31861063

RESUMEN

Seed germination and seedling root development are important indicators of plant development. This work designed and fabricated a foldable microfluidic chip array for conducting nondestructive and continuous evaluation of seed germination and subsequent seedling development in situ. Each plant chamber has two functional units: seed germination part and root-growth part. The root-growth parts are themselves connected to a single channel designed to provide a uniform culture medium for plant growth. The individual chips are connected into an array using elastic hinges that facilitate the folding and unfolding of the array to accommodate different viewing purposes. In the folded state, the seed germination chambers form a closely spaced array platform to facilitate the comparison of seed germination and plant development characteristics. Unfolding the array facilitates a clear examination of root development within the root-growth parts. The observation window of an individual chip facilitates either the direct examination of the developing seedling (e.g., stems and leaves) or the use of a microscope for examining microscale features (e.g., root tips and root hairs). The potential of the proposed foldable chip array as a new cultivation platform for botanic studies is demonstrated by examining the seed germination and seedling development of tobacco (Nicotiana tabacum) under different cultivation conditions.

16.
Planta ; 250(3): 803-820, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31267230

RESUMEN

MAIN CONCLUSION: Bambara groundnut has the potential to be used to contribute more the climate change ready agriculture. The requirement for nitrogen fixing, stress tolerant legumes is clear, particularly in low input agriculture. However, ensuring that existing negative traits are tackled and demand is stimulated through the development of markets and products still represents a challenge to making greater use of this legume. World agriculture is currently based on very limited numbers of crops, representing a significant risk to food supplies, particularly in the face of climate change which is expected to increase the frequency of extreme events. Minor and underutilised crops can help to develop a more resilient and nutritionally dense future agriculture. Bambara groundnut [Vigna subterranea (L.) Verdc.[, as a drought resistant, nitrogen-fixing, legume has a role to play. However, as with most underutilised crops, there are significant gaps in knowledge and also negative traits such as 'hard-to-cook' and 'photoperiod sensitivity to pod filling' associated with the crop which future breeding programmes and processing methods need to tackle, to allow it to make a significant contribution to the well-being of future generations. The current review assesses these factors and also considers what are the next steps towards realising the potential of this crop.


Asunto(s)
Cambio Climático , Productos Agrícolas , Vigna , Culinaria/métodos , Producción de Cultivos/métodos , Productos Agrícolas/genética , Productos Agrícolas/crecimiento & desarrollo , Vigna/genética , Vigna/crecimiento & desarrollo
17.
Lab Chip ; 19(14): 2383-2393, 2019 07 21.
Artículo en Inglés | MEDLINE | ID: mdl-31187104

RESUMEN

The root system of plants is a major component of their bodies in terms of both function and bulk. The investigation of root system development is greatly assisted by microfluidic devices, which improve the spatial and temporal resolution of observations without destroying tissue. In the present study, a multi-chamber petaloid root-growth chip was developed for studying the development and physiology of root systems that have thin branching structures (i.e., fibrous root systems). The petaloid root-growth chip includes a central seed germination chamber and five root-growth chambers for observing the development of fibrous roots. The proposed device was applied for investigating the root system development of Oryza sativa. The phenotype and growth kinetics of O. sativa root systems grown in the proposed device were compared with those obtained during growth in a conventional conical flask with agar-based medium, and the results indicated that cultivation in the miniaturized device did not delay root system growth in the early stage (≤2 weeks). In addition, the transparent device enabled the non-destructive observation of the developmental and microstructural characteristics of the roots, such as the root caps, root border cells, and root hairs. Moreover, the ability to control the microenvironment in each of the five root-growth chambers individually facilitated the investigation of specific adaptations in the fibrous root growth of single O. sativa seedlings to different drought stresses. Accordingly, five polyethylene glycol (PEG)6000-induced drought stress conditions were established in the five root-growth chambers to investigate the root development of a single O. sativa seedling in the central germination chamber. In situ observations demonstrated that the different PEG6000-induced conditions affected the root growth responses and root microstructural adaptations of the single seedlings in each root-growth chamber. Therefore, the petaloid root-growth microfluidic chip can eliminate the effects of variations in different plant seeds to reveal the responses of plants to different environmental conditions more objectively while concurrently allowing for non-destructive observations at very high spatial and temporal resolution.


Asunto(s)
Técnicas de Cultivo/instrumentación , Dispositivos Laboratorio en un Chip , Oryza/crecimiento & desarrollo , Raíces de Plantas/crecimiento & desarrollo , Sequías , Germinación , Oryza/fisiología , Raíces de Plantas/fisiología , Semillas/crecimiento & desarrollo , Estrés Fisiológico
18.
FASEB J ; 33(8): 8853-8864, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31034777

RESUMEN

Depression is increasingly recognized as an inflammatory disease, with inflammatory crosstalk in the brain contributing its pathogenesis. Life stresses may up-regulate inflammatory processes and promote depression. Although cytokines are central to stress-related immune responses, their contribution to stress-induced depression remains unclear. Here, we used unpredictable chronic mild stress (UCMS) to induce depression-like behaviors in mice, as assessed through a suite of behavioral tests. C-X-C motif chemokine ligand 1 (CXCL1)-related molecular networks responsible for depression-like behaviors were assessed through intrahippocampal microinjection of lenti-CXCL1, the antidepressant fluoxetine, the C-X-C motif chemokine receptor 2 (CXCR2) inhibitor SB265610, and the glycogen synthase kinase-3ß (GSK3ß) inhibitor AR-A014418. Modulation of apoptosis-related pathways and neuronal plasticity were assessed via quantification of cleaved caspase-3, B-cell lymphoma 2-associated X protein, cAMP response element-binding protein (CREB), and brain-derived neurotrophic factor (BDNF) protein expression. CXCL1/CXCL2 expression was correlated with depression-like behaviors in response to chronic stress or antidepressant treatment in the UCMS depression model. Intrahippocampal microinjection of lenti-CXCL1 increased depression-like behaviors, activated GSK3ß, increased apoptosis pathways, suppressed CREB activation, and decreased BDNF. Administration of the selective GSK3ß inhibitor AR-A014418 abolished the effects of lenti-CXCL1, and the CXCR2 inhibitor SB265610 prevented chronic stress-induced depression-like behaviors, inhibited GSK3ß activity, blocked apoptosis pathways, and restored BDNF expression. The CXCL1/CXCR2 axis appears to play a critical role in stress-induced depression, and CXCR2 is a potential novel therapeutic target for patients with depression.-Chai, H.-H., Fu, X.-C., Ma, L., Sun, H.-T., Chen, G.-Z., Song, M.-Y., Chen, W.-X., Chen, Y.-S., Tan, M.-X., Guo, Y.-W., Li, S.-P. The chemokine CXCL1 and its receptor CXCR2 contribute to chronic stress-induced depression in mice.


Asunto(s)
Quimiocina CXCL1/metabolismo , Depresión/metabolismo , Receptores de Interleucina-8B/metabolismo , Animales , Antidepresivos de Segunda Generación/farmacología , Apoptosis , Factor Neurotrófico Derivado del Encéfalo/genética , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Quimiocina CXCL1/genética , Depresión/etiología , Depresión/genética , Fluoxetina/farmacología , Glucógeno Sintasa Quinasa 3 beta/genética , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Plasticidad Neuronal , Compuestos de Fenilurea/farmacología , Receptores de Interleucina-8B/genética , Estrés Psicológico/complicaciones , Tiazoles/farmacología , Triazoles/farmacología , Urea/análogos & derivados , Urea/farmacología
19.
RSC Adv ; 9(66): 38590-38596, 2019 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-35540181

RESUMEN

A novel colorimetric aptasensor based on a Au/Fe3O4 nanohybrid was developed to detect ochratoxin A (OTA). The aptasensor is composed of a free OTA aptamer, a Au/Fe3O4 nanohybrid coated with biotinylated complementary DNA of the OTA aptamer (biotin-cDNA-Au/Fe3O4), and free alkaline-phosphatase-labeled streptavidin (SA-ALP). The Au/Fe3O4 nanohybrid not only immobilizes biotin-cDNA but also magnetically separates SA-ALP from the sample solution. One part of the OTA aptamer sequence hybridizes with biotin-cDNA immobilized on Au/Fe3O4, and the left part of the OTA aptamer sequence covers the biotin and blocks the specific interaction between biotin and SA-ALP. OTA can interrupt the interaction of OTA aptamer binding to biotin-cDNA-Au/Fe3O4 and can inhibit the shielding effect of the OTA aptamer on biotin. The amount of SA-ALP that can be captured by biotin-cDNA-Au/Fe3O4 thus increases with increasing OTA concentration. Through a simple magnetic separation, the collected SA-ALP-linked Au/Fe3O4 can produce a yellow-colored solution in the presence of p-nitrophenyl phosphate (p-NPP). This colorimetric aptasensor can detect OTA as low as 1.15 ng mL-1 with high specificity.

20.
Biomed Opt Express ; 9(10): 4604-4612, 2018 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-30319889

RESUMEN

A smartphone-based image analysis system is advantageous for point-of-care testing applications. However, the processes of observation and image recording rely heavily on an external attachment that includes additional light sources. Moreover, microfluidic point-of-care devices are highly miniaturized, and can be clearly observed only under magnification. To address these issues, the present work proposes a novel imaging box for converting the built-in light source of a smartphone into uniform backlight illumination to avoid interference arising from reflections. A multi-piece orthoscopic lens is embedded in the imaging box to enable the imaging of micro-sized samples. As such, the colorimetric signal of a microchannel with a width as small as 25 µm can be faithfully recorded. Protein concentration quantification based on the bicinchoninic acid assay method was demonstrated with the proposed smartphone/imaging box system from an analysis of colorimetric signals. In addition, a microfluidic chip for conducting ABO blood typing was fabricated, and the microscopic imaging of induced blood coagulation can be clearly observed in a 3 µL sample using the proposed system. These results highlight the potential for adopting smartphone-based analysis systems in point-of-care testing applications.

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