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1.
Am J Obstet Gynecol ; 230(6): 600-609.e3, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38128862

ABSTRACT

INTRODUCTION: The lifetime risk of urinary tract infection is known from first-degree relative studies to be highly heritable. Associations have also been observed across the life course from pediatric urinary tract infection to recurrent urinary tract infection in adulthood, suggesting lifelong susceptibility factors. Candidate gene studies and genome-wide association studies have tested for genetic associations of urinary tract infection; however, no contemporary systematic synthesis of studies is available. OBJECTIVE: We conducted a systematic review to identify all genetic polymorphisms tested for an association with urinary tract infection in children and adults; and to assess their strength, consistency, and risk of bias among reported associations. DATA SOURCES AND STUDY ELIGIBILITY CRITERIA: PubMed, HuGE Navigator and Embase were searched from January 1, 2005 to November 16, 2023, using a combination of genetic and phenotype key words. STUDY APPRAISAL AND SYNTHESIS METHODS: Fixed and random effects meta-analyses were conducted using codominant models of inheritance in metan. The interim Venice criteria were used to assess their credibility of pooled associations. RESULTS: After removing 451 duplicates, 1821 studies reports were screened, with 106 selected for full-text review, 22 were included in the meta-analysis (7 adult studies and 15 pediatric studies). Our meta-analyses demonstrated significant pooled associations for pediatric urinary tract infection with variation in CXCR1, IL8, TGF, TLR4 and VDR; all of which have plausible roles in the pathogenesis of urinary tract infection. Our meta-analyses also demonstrated a significant pooled association for adult urinary tract infection with variation in CXCR1. All significant pooled associations were graded according to their epidemiological credibility, sample sizes, heterogeneity between studies, and risk of bias. CONCLUSION: This systematic review provides a current synthesis of the known genetic architecture of urinary tract infection in childhood and adulthood; and should provide important information for researchers analysing future genetic association studies. Although, overall, the credibility of pooled associations was weak, the consistency of findings for rs2234671 single nucleotide polymorphisms of CXCR1 in both populations suggest a key role in the urinary tract infection pathogenesis.


Subject(s)
Genetic Predisposition to Disease , Urinary Tract Infections , Humans , Urinary Tract Infections/genetics , Child , Adult , Polymorphism, Single Nucleotide , Polymorphism, Genetic , Genome-Wide Association Study
2.
Microb Cell Fact ; 23(1): 153, 2024 May 25.
Article in English | MEDLINE | ID: mdl-38796416

ABSTRACT

BACKGROUND: Dihydroxyacetone (DHA) stands as a crucial chemical material extensively utilized in the cosmetics industry. DHA production through the dephosphorylation of dihydroxyacetone phosphate, an intermediate product of the glycolysis pathway in Escherichia coli, presents a prospective alternative for industrial production. However, insights into the pivotal enzyme, dihydroxyacetone phosphate dephosphorylase (HdpA), remain limited for informed engineering. Consequently, the development of an efficient tool for high-throughput screening of HdpA hypermutants becomes imperative. RESULTS: This study introduces a methylglyoxal biosensor, based on the formaldehyde-responding regulator FrmR, for the selection of HdpA. Initial modifications involved the insertion of the FrmR binding site upstream of the -35 region and into the spacer region between the -10 and -35 regions of the constitutive promoter J23110. Although the hybrid promoter retained constitutive expression, expression of FrmR led to complete repression. The addition of 350 µM methylglyoxal promptly alleviated FrmR inhibition, enhancing promoter activity by more than 40-fold. The methylglyoxal biosensor system exhibited a gradual increase in fluorescence intensity with methylglyoxal concentrations ranging from 10 to 500 µM. Notably, the biosensor system responded to methylglyoxal spontaneously converted from added DHA, facilitating the separation of DHA producing and non-producing strains through flow cytometry sorting. Subsequently, the methylglyoxal biosensor was successfully applied to screen a library of HdpA mutants, identifying two strains harboring specific mutants 267G > T and D110G/G151C that showed improved DHA production by 68% and 114%, respectively. Expressing of these two HdpA mutants directly in a DHA-producing strain also increased DHA production from 1.45 to 1.92 and 2.29 g/L, respectively, demonstrating the enhanced enzyme properties of the HdpA mutants. CONCLUSIONS: The methylglyoxal biosensor offers a novel strategy for constructing genetically encoded biosensors and serves as a robust platform for indirectly determining DHA levels by responding to methylglyoxal. This property enables efficiently screening of HdpA hypermutants to enhance DHA production.


Subject(s)
Biosensing Techniques , Dihydroxyacetone , Escherichia coli , Pyruvaldehyde , Pyruvaldehyde/metabolism , Biosensing Techniques/methods , Dihydroxyacetone/metabolism , Escherichia coli/metabolism , Escherichia coli/genetics , Promoter Regions, Genetic , Metabolic Engineering/methods , Escherichia coli Proteins/metabolism , Escherichia coli Proteins/genetics
3.
Metab Eng ; 75: 170-180, 2023 01.
Article in English | MEDLINE | ID: mdl-36566973

ABSTRACT

Currently, the biological production of L-malic acid (L-MA) is mainly based on the fermentation of filamentous fungi at near-neutral pH, but this process requires large amounts of neutralizing agents, resulting in the generation of waste salts when free acid is obtained in the downstream process, and the environmental hazards associated with the waste salts limit the practical application of this process. To produce L-MA in a more environmentally friendly way, we metabolically engineered the acid-tolerant yeast Pichia kudriavzevii and achieved efficient production of L-MA through low pH fermentation. First, an initial L-MA-producing strain that relies on the reductive tricarboxylic acid (rTCA) pathway was constructed. Subsequently, the L-MA titer and yield were further increased by fine-tuning the flux between the pyruvate and oxaloacetate nodes. In addition, we found that the insufficient supply of NADH for cytoplasmic malate dehydrogenase (MDH) hindered the L-MA production at low pH, which was resolved by overexpressing the soluble pyridine nucleotide transhydrogenase SthA from E. coli. Transcriptomic and metabolomic data showed that overexpression of EcSthA contributed to the activation of the pentose phosphate pathway and provided additional reducing power for MDH by converting NADPH to NADH. Furthermore, overexpression of EcSthA was found to help reduce the accumulation of the by-product pyruvate but had no effect on the accumulation of succinate. In microaerobic batch fermentation in a 5-L fermenter, the best strain, MA009-10-URA3 produced 199.4 g/L L-MA with a yield of 0.94 g/g glucose (1.27 mol/mol), with a productivity of 1.86 g/L/h. The final pH of the fermentation broth was approximately 3.10, meaning that the amount of neutralizer used was reduced by more than 50% compared to the common fermentation processes using filamentous fungi. To our knowledge, this is the first report of the efficient bioproduction of L-MA at low pH and represents the highest yield of L-MA in yeasts reported to date.


Subject(s)
Escherichia coli , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genetics , Escherichia coli/genetics , Metabolic Engineering/methods , NAD/metabolism , Salts/metabolism , Fermentation , Pyruvates/metabolism , Hydrogen-Ion Concentration
4.
J Bioenerg Biomembr ; 55(3): 195-205, 2023 06.
Article in English | MEDLINE | ID: mdl-37237241

ABSTRACT

Adipose tissue-derived mesenchymal stem cells (ADSCs) have promising effects on nerve repair due to the differentiation ability to neural cells. Ghrelin has been shown to promote the neural differentiation of ADSCs. This work was designed to explore its underlying mechanism. Herein, we found high expression of LNX2 in ADSCs after neuronal differentiation. Knockdown of LNX2 might block neuronal differentiation of ADSCs, as evidenced by the decreased number of neural-like cells and dendrites per cell, and the reduced expressions of neural markers (including ß-Tubulin III, Nestin, and MAP2). We also demonstrated that LNX2 silencing suppressed the nuclear translocation of ß-catenin in differentiated ADSCs. Luciferase reporter assay indicated that LNX2 inhibited wnt/ß-catenin pathway by reducing its transcriptional activity. In addition, results showed that LNX2 expression was increased by ghrelin, and its inhibition diminished the effects of ghrelin on neuronal differentiation. Altogether, the results suggest that LNX2 is involved in the role of ghrelin to facilitate neuronal differentiation of ADSCs.


Subject(s)
Ghrelin , Mesenchymal Stem Cells , beta Catenin , beta Catenin/metabolism , Cell Differentiation/physiology , Cells, Cultured , Ghrelin/pharmacology , Ghrelin/metabolism , Mesenchymal Stem Cells/metabolism , Neurons/metabolism , Humans
5.
Opt Express ; 30(13): 24084-24102, 2022 Jun 20.
Article in English | MEDLINE | ID: mdl-36225077

ABSTRACT

With the presence of complex background noise, parasitic light, and dust attachment, it is still a challenging issue to perform high-precision laser-induced damage change detection of optical elements in the captured optical images. For resolving this problem, this paper presents an end-to-end damage change detection model based on siamese network and multi-layer perceptrons (SiamMLP). Firstly, representative features of bi-temporal damage images are efficiently extracted by the cascaded multi-layer perceptron modules in the siamese network. After that, the extracted features are concatenated and then classified into changed and unchanged classes. Due to its concise architecture and strong feature representation ability, the proposed method obtains excellent damage change detection results efficiently and effectively. To address the unbalanced distribution of hard and easy samples, a novel metric called hard metric is introduced in this paper for quantitatively evaluating the classification difficulty degree of the samples. The hard metric assigns a classification difficulty for each individual sample to precisely adjust the loss assigned to the sample. In the training stage, a novel hard loss is presented to train the proposed model. Cooperating with the hard metric, the hard loss can up-weight the loss of hard samples and down-weight the loss of easy samples, which results in a more powerful online hard sample mining ability of the proposed model. The experimental results on two real datasets validate the effectiveness and superiority of the proposed method.

6.
J Surg Res ; 280: 411-420, 2022 12.
Article in English | MEDLINE | ID: mdl-36041341

ABSTRACT

INTRODUCTION: Studies indicate that learning surgical skills on low-fidelity models is equally beneficial to learning on high-fidelity models in terms of skills retention and transfer. However, it is unclear how low-fidelity simulation training impacts retention and transfer in novice learners, particularly on complex surgical tasks that incorporate multiple challenging skills. This study explores the capacity of complete novices to learn and transfer complex surgical skills from a low-fidelity model to a high-fidelity simulation after a delay. METHODS: Task-naïve medical and nonmedical undergraduate students (n = 62) participated in a three-phase prospective double-arm randomized (2:1) experimental study. Participants completed two skills training sessions (end-to-side anastomosis) on a low-fidelity bench model. After a 4-week delay, participants completed the task again either using the low-fidelity model or a high-fidelity model (cadaver) and were assessed using a validated checklist. RESULTS: There was a significant time × fidelity group interaction (P = 0.004). Simple effects analysis indicated the high-fidelity group (Mdiff = 4.18, P < 0.001) performed significantly worse (P = 0.003) in phase 3 relative to phase 2 compared to the low-fidelity group (Mdiff = 0.75, P = 0.39). Post hoc logistic regression analysis indicated that radial suturing technique and economy of motion skills were less likely to be completed correctly for those in the high-fidelity group. CONCLUSIONS: These findings suggest that for novice populations, relying on low-fidelity simulation training as a source of teaching complex skills may not provide a reliable transfer to high-fidelity models and in turn clinical settings.


Subject(s)
Clinical Competence , Simulation Training , Humans , Prospective Studies , Simulation Training/methods , Learning , Cadaver
7.
Anal Bioanal Chem ; 414(23): 6791-6800, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35931786

ABSTRACT

Folic acid (FA) is essential for human health, particularly for pregnant women and infants. In this work, a glassy carbon electrode (GCE) was modified by a bimetallic layer of Cu/Co nanoparticles (CuNPs/CoNPs) as a synergistic amplification element by simple step-by-step electrodeposition, and was used for sensitive detection of FA. The proposed CuNPs/CoNPs/GCE sensor was characterized by differential pulse voltammetry (DPV), electrochemical impedance spectroscopy (EIS) and field emission scanning electron microscopy (FESEM). Then, under optimal conditions, a linear relationship was obtained in the wide range of 110.00-1750.00 µM for the detection of FA with a limit of detection (LOD) of 34.79 µM (S/N = 3). The sensitivity was calculated as 0.096 µA µM-1 cm-2. Some interfering compounds including glucose (Glc), biotin, dopamine (DA), and glutamic acid (Glu) showed little effect on the detection of FA by amperometry (i-t). Finally, the average recovery obtained was in a range of 91.77-110.06%, with a relative standard deviation (RSD) less than 8.00% in FA tablets, indicating that the proposed sensor can accurately and effectively detect the FA content in FA tablets.


Subject(s)
Carbon , Electrochemical Techniques , Electrochemical Techniques/methods , Electrodes , Female , Folic Acid , Humans , Limit of Detection , Pregnancy , Tablets
8.
Macromol Rapid Commun ; 43(22): e2200591, 2022 Nov.
Article in English | MEDLINE | ID: mdl-35962718

ABSTRACT

Wide bandgap polymers with a donor-acceptor alternating structure play a key role in constructing high-efficiency organic solar cells (OSCs). However, only a handful of high-performance polymers are available owing to the limited choices of acceptor units. 5,6-Difluorobenzo[c][1,2,5]oxadiazole (ffBX) is a promising acceptor unit with high ionization potential, and can afford high charge carrier mobility and strong aggregation for the resulting polymers. Historically, ffBX is successfully used in constructing high-performance polymer donors for fullerene-based OSCs. However, this unit is far less been explored in non-fullerene OSCs. In this work, three ffBX-based wide bandgap polymers (Oc00, Oc25, and Oc50) with varied solubilizing side chain content for application in non-fullerene OSCs are reported. The polymers show matched energy levels and complementary optical absorption with the state-of-the-art non-fullerene acceptor Y6. Moreover, the polymer solubility, solid state packing, and bulk-heterojunction morphology are finely tuned via side chain engineering. Encouragingly, a decent efficiency of 14.25% is realized by the polymer Oc25 when blended with Y6 due to the efficient charge transport and favorable active layer morphology. These results suggest the promising prospect of ffBX in constructing high-performance polymer donors for non-fullerene OSCs.

9.
Sensors (Basel) ; 22(7)2022 Mar 31.
Article in English | MEDLINE | ID: mdl-35408290

ABSTRACT

Recently, a frequency diverse array (FDA) has been employed in an orthogonal frequency division multiplexing (OFDM) transmitter to achieve secure wireless communication without mathematical encryption. However, an insecure coupling effect arises if the frequency increments are linearly assigned to all antenna elements. To solve this problem, random subcarrier-selection methods are proposed; however, the challenge lies in the random selection of subcarriers. Inspired by the randomness of index modulation (IM), this paper proposes a low complexity random subcarrier-selection method based on index modulation (RSCS-IM). Specifically, this work conducted analysis on the spectral efficiency (SE) of our system and the computational complexity of RSCS-IM, which works out a closed-form expression of the BER performance of a desired position and validates the theoretical outcomes through simulation.


Subject(s)
Telecommunications , Computer Simulation , Equipment Design , Signal Processing, Computer-Assisted
10.
Metab Eng ; 68: 232-245, 2021 11.
Article in English | MEDLINE | ID: mdl-34710614

ABSTRACT

Harnessing mitochondria is considered as a promising method for biosynthesis of terpenes due to the adequate supply of acetyl-CoA and redox equivalents in mitochondria. However, mitochondrial engineering often causes serious metabolic burden indicated by poor cell growth. Here, we systematically analyzed the metabolic burden caused by the compartmentalization of the MVA pathway in yeast mitochondria for squalene synthesis. The phosphorylated intermediates of the MVA pathway, especially mevalonate-5-P and mevalonate-5-PP, conferred serious toxicity within mitochondria, which significantly compromised its possible advantages for squalene synthesis and was difficult to be significantly improved by routine pathway optimization. These phosphorylated intermediates were converted into ATP analogues, which strongly inhibited ATP-related cell function, such as mitochondrial oxidative respiration. Fortunately, the introduction of a partial MVA pathway from acetyl-CoA to mevalonate in mitochondria as well as the augmentation of the synthesis of mevalonate in cytosol could significantly promote the growth of yeasts. Accordingly, a combinatorial strategy of cytoplasmic and mitochondrial engineering was proposed to alleviate the metabolic burden caused by the compartmentalized MVA pathway in mitochondria and improve cell growth. The strategy also displayed the superimposed effect of cytoplasmic engineering and mitochondrial engineering on squalene production. Through a two-stage fermentation process, the squalene titer reached 21.1 g/L with a specific squalene titer of 437.1 mg/g dcw, which was the highest at present. This provides new insight into the production of squalene and other terpenes in yeasts based on the advantages of mitochondrial engineering.


Subject(s)
Saccharomyces cerevisiae , Squalene , Acetyl Coenzyme A , Metabolic Engineering , Mitochondria/genetics , Saccharomyces cerevisiae/genetics
11.
Opt Express ; 29(13): 20673-20686, 2021 Jun 21.
Article in English | MEDLINE | ID: mdl-34266151

ABSTRACT

We demonstrate an approach to double the optical efficiency of virtual reality (VR) systems based on a directional backlight and a diffractive deflection film (DDF). The directional backlight consists of a commercial collimated light-emitting diode (LED) array and a two-layer privacy film, while the DDF is a three-domain Pancharatnam-Berry (PB) phase lens. Such a PB phase lens was fabricated by the zone exposure and spin-coating method. The focal length of each domain is designed according to the imaging optics of the VR system. Our approach works well in both Fresnel and "pancake" VR systems. We also build the corresponding models in LightTools, and the simulation results are in good agreement with experiment. In experiment, we achieved a 2.25x optical efficiency enhancement for both systems, which agrees with the simulation results (2.48x for Fresnel and 2.44x for "pancake" systems) well. Potential application for high efficiency VR displays is foreseeable.

12.
Opt Express ; 29(4): 6011-6020, 2021 Feb 15.
Article in English | MEDLINE | ID: mdl-33726132

ABSTRACT

A planar and broadband cholesteric liquid crystal (CLC) lens is designed, fabricated, and hybridized with a refractive lens to form a catadioptric pancake lens for virtual reality (VR) displays. Due to their opposite optical dispersion behaviors, the chromatic aberration of the assembled pancake lens is dramatically suppressed, as verified by both ray-tracing analysis and experimental results. The demonstrated catadioptric pancake lens has great potential for next-generation VR displays.

13.
Chemistry ; 27(54): 13527-13533, 2021 Sep 24.
Article in English | MEDLINE | ID: mdl-34406681

ABSTRACT

Conjugated molecules and polymers with intrinsic quinoidal structure are promising n-type organic semiconductors, which have been reported for application in field-effect transistors and thermoelectric devices. In principle, the molecular and electronic characteristics of quinoidal polymers can also enable their application in organic solar cells. Herein, two quinoidal polymers, named PzDP-T and PzDP-ffT, based on dipyrrolopyrazinedione were synthesized and used as electron acceptors in all-polymer solar cells (all-PSCs). Both PzDP-T and PzDP-ffT showed suitable energy levels and wide light absorption range that extended to the near-infrared region. When combined with the polymer donor PBDB-T, the resulting all-PSCs based on PzDP-T and PzDP-ffT exhibited a power conversion efficiency (PCE) of 1.33 and 2.37 %, respectively. This is the first report on the application of intrinsic quinoidal conjugated polymers in all-PSCs. The photovoltaic performance of the all-PSCs was revealed to be mainly limited by the relatively poor and imbalanced charge transport, considerable charge recombination. Detailed investigations on the structure-performance relationship suggested that synergistic optimization of light absorption, energy levels, and charge transport properties is needed to achieve more successful application of intrinsic quinoidal conjugated polymers in all-PSCs.

14.
FASEB J ; 34(6): 8526-8543, 2020 06.
Article in English | MEDLINE | ID: mdl-32359120

ABSTRACT

Opioid analgesics remain the mainstay for managing intractable chronic pain, but their use is limited by detrimental side effects such as analgesic tolerance and hyperalgesia. Calcium-dependent synaptic plasticity is a key determinant in opiates tolerance and hyperalgesia. However, the exact substrates for this calcium-dependent synaptic plasticity in mediating these maladaptive processes are largely unknown. Canonical transient receptor potential 1, 4, and 5 (TRPC1, 4, 5) proteins assemble into heteromultimeric nonselective cation channels with high Ca2+ permeability and influence various neuronal functions. However, whether and how TRPC1/4/5 channels contribute to the development of opiates tolerance and hyperalgesia remains elusive. Here, we show that TRPC1/4/5 channels contribute to the generation of morphine tolerance and hyperalgesia. Chronic morphine exposure leads to upregulation of TRPC1/4/5 channels in the spinal cord. Spinally expressed TRPC1, TPRC4, and TRPC5 are required for chronic morphine-induced synaptic long-term potentiation (LTP) as well as remodeling of synaptic spines in the dorsal horn, thereby orchestrating functional and structural plasticity during the course of morphine-induced hyperalgesia and tolerance. These effects are attributed to TRPC1/4/5-mediated Ca2+ elevation in the spinal dorsal horn induced by chronic morphine treatment. This study identifies TRPC1/4/5 channels as a promising novel target to prevent the unwanted morphine tolerance and hyperalgesia.


Subject(s)
Hyperalgesia/chemically induced , Hyperalgesia/metabolism , Morphine/pharmacology , Neuronal Plasticity/physiology , Spinal Cord/metabolism , TRPC Cation Channels/metabolism , Analgesics/pharmacology , Analgesics, Opioid/pharmacology , Animals , Drug Tolerance/physiology , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Neuronal Plasticity/drug effects , Neurons/drug effects , Neurons/metabolism , Spinal Cord/drug effects , Spinal Cord Dorsal Horn/drug effects , Spinal Cord Dorsal Horn/metabolism
15.
J Ind Microbiol Biotechnol ; 48(7-8)2021 Aug 24.
Article in English | MEDLINE | ID: mdl-34196357

ABSTRACT

D-glycerate is an attractive chemical for a wide variety of pharmaceutical, cosmetic, biodegradable polymers, and other applications. Now several studies have been reported about the synthesis of glycerate by different biotechnological and chemical routes from glycerol or other feedstock. Here, we present the construction of an Escherichia coli engineered strain to produce optically pure D-glycerate by oxidizing glycerol with an evolved variant of alditol oxidase (AldO) from Streptomyces coelicolor. This is achieved by starting from a previously reported variant mAldO and employing three rounds of directed evolution, as well as the combination of growth-coupled high throughput selection with colorimetric screening. The variant eAldO3-24 displays a higher substrate affinity toward glycerol with 5.23-fold than the wild-type AldO, and a 1.85-fold increase of catalytic efficiency (kcat/KM). Then we introduced an isopropyl-ß-D-thiogalactopyranoside (IPTG)-inducible T7 expression system in E. coli to overexpress the variant eAldO3-24, and deleted glucosylglycerate phosphorylase encoding gene ycjM to block the consumption of D-glycerate. Finally, the resulting strain TZ-170 produced 30.1 g/l D-glycerate at 70 h with a yield of 0.376 mol/mol in 5-l fed-batch fermentation.


Subject(s)
Glycerol , Streptomyces coelicolor , Escherichia coli/genetics , Fermentation , Oxidoreductases , Sugar Alcohols
16.
Can J Surg ; 64(2): E191-E195, 2021 03 19.
Article in English | MEDLINE | ID: mdl-33739804

ABSTRACT

Background: Prompt Doppler ultrasonography to aid in diagnosis is often key to managing testicular torsion, but there may be delays in access; a faster, more widely available alternative is point-of-care ultrasonography (POCUS). The purpose of this study was to develop and evaluate a scrotal POCUS curriculum for urology and emergency medicine residents. Methods: Content experts in urology, emergency medicine and diagnostic imaging collaborated in a modified Delphi method to design a practical didactic curriculum for scrotal POCUS for the identification of testicular torsion. Training included 3 online video teaching modules and a 1-hour hands-on teaching session with standardized adult patients. We evaluated participants' competency in scrotal POCUS using a validated scale. We assessed participants' knowledge, comfort and confidence in performing scrotal POCUS before and after the intervention and at 3 months. Results: Twenty-four urology (n = 12) and emergency medicine (n = 12) residents participated in the curriculum. After hands-on practice, 23 participants (96%) were deemed competent at scrotal POCUS. Pre-post testing showed significant improvement in knowledge (mean score 63% v. 80%, p < 0.001), comfort (mean Likert score 0.6 v. 3.6, p < 0.001) and confidence (mean Likert score 1.0 v. 2.1, p < 0.001) after the intervention. These effects were maintained at the 3-month assessment. Conclusion: The scrotal POCUS curriculum was effective and acceptable to both urology and emergency medicine residents. The findings suggest that scrotal POCUS can be learned effectively through a short hands-on session and didactic instruction.


Contexte: Le diagnostic rapide d'une torsion testiculaire à l'aide d'une échographie Doppler est souvent crucial à la prise en charge de ce trouble. Or, comme l'accès à cet examen peut être limité, l'échographie portable constitue une solution de rechange rapide et largement accessible. La présente étude visait la mise au point et l'évaluation d'un programme de formation sur l'échographie portable scrotale destiné aux résidents en urologie et en médecine d'urgence. Méthodes: Des experts en urologie, en médecine d'urgence et en imagerie diagnostique se sont servis d'une méthode Delphi modifiée pour concevoir un programme de formation sur l'échographie portable visant à faciliter le diagnostic de la torsion testiculaire. Ce programme comprenait 3 modules d'apprentissage vidéo en ligne, ainsi qu'une séance pratique d'une heure auprès de patients adultes normalisés. Nous avons évalué les compétences des participants en matière d'échographie portable scrotale au moyen d'une échelle validée. Nous avons également évalué les connaissances, l'aisance et le niveau de confiance des participants à l'égard de cet examen avant et immédiatement après la formation, puis 3 mois plus tard. Résultats: Au total, 24 résidents en urologie (n = 12) et en médecine d'urgence (n = 12) ont suivi le programme de formation. Après la séance pratique, 23 participants (96 %) avaient les compétences nécessaires à la réalisation d'une échographie portable scrotale. La comparaison des résultats obtenus avant et immédiatement après la formation a montré une augmentation significative des connaissances (note moyenne : 63 % c. 80 %; p < 0,001), de l'aisance (moyenne à l'échelle de Likert : 0,6 c. 3,6; p < 0,001) et du niveau de confiance (moyenne à l'échelle de Likert : 1,0 c. 2,1; p < 0,001) des participants. Les effets de la formation étaient toujours présents 3 mois plus tard. Conclusion: Le programme de formation sur l'échographie portable scrotale s'est avéré efficace et acceptable pour les résidents en urologie et en médecine d'urgence. Les résultats obtenus laissent croire qu'une formation pédagogique et une courte séance d'apprentissage pratique permettent l'enseignement efficace de l'échographie portable scrotale.


Subject(s)
Curriculum , Emergency Medicine/education , Internship and Residency , Point-of-Care Systems , Spermatic Cord Torsion/diagnostic imaging , Urology/education , Humans , Male , Ultrasonography
17.
Opt Express ; 28(4): 5875-5882, 2020 Feb 17.
Article in English | MEDLINE | ID: mdl-32121802

ABSTRACT

We use a simple photoalignment method to fabricate four reflective cholesteric liquid crystal (CLC) polymeric lenses with diameter D=2.45 cm and low f-numbers (f/2, f/0.9, f/0.45, f/0.33) at 550 nm. Such a flat CLC lens can be converging or diverging, depending on the handedness and direction of the incident light. Our CLC lenses can achieve ∼85% diffraction efficiency for a designated polarization state and manifest decent imaging ability.

18.
Opt Express ; 28(9): 13907-13912, 2020 Apr 27.
Article in English | MEDLINE | ID: mdl-32403856

ABSTRACT

We demonstrate an absorption-based polarization grating made of dichroic dye-doped polymerizable liquid crystal. These gratings manifest a polarization-sensitive diffraction efficiency over the absorption band of the employed dye material, based on our theoretical analysis and experimental evidence. The spectral range can be easily tailored by varying the dye material. Since these gratings generate first-order diffracted beams with orthogonal circular polarizations, they can be utilized as key components in polarimetry systems. Meanwhile, due to their absorptive nature, these polarization gratings can function as LED-compatible polarization masks for photopatterning while fabricating various liquid crystal devices.

19.
Opt Express ; 28(26): 38616-38625, 2020 Dec 21.
Article in English | MEDLINE | ID: mdl-33379428

ABSTRACT

Maxwellian view systems can be employed to circumvent the vergence-accommodation conflict in near-eye displays (NEDs), which directly project images onto the retina regardless of the human eye's depth of focus. However, Maxwellian view optics typically have a limited eyebox, which prevents broader applications of this architecture in NEDs. Here, we demonstrate a thin-film two-dimensional beam deflector composed of multi-twist broad-band Pancharatnam-Berry deflectors to mitigate this limitation via eyebox replication. Based on experimental validation, our proposed design can display always-focused full-color images within a 9 mm × 9 mm eyebox and thus mitigate the limitation of conventional Maxwellian displays while adding negligible weight and volume.

20.
Opt Express ; 28(4): 4921-4927, 2020 Feb 17.
Article in English | MEDLINE | ID: mdl-32121722

ABSTRACT

We demonstrate a high-efficiency achromatic, wide-view Pancharatnam-Berry phase deflector (PBD) based on a three-layer multi-twist structure. A practical method to measure the thickness and twist angle of liquid crystal (LC) polymer films is developed based on Jones matrix of twist-nematic liquid crystals. With the help of this new measurement method, we fabricated a three-layer multi-twist PBD. The imaging performance and the angular response of the achromatic wide-view PBD are also characterized. Potential application of PBD for near-eye displays is foreseeable.

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