Point-of-Care Brain MRI: Preliminary Results from a Single-Center Retrospective Study.

Background Point-of-care (POC) MRI is a bedside imaging technology with fewer than five units in clinical use in the United States and a paucity of scientific studies on clinical applications. Purpose To evaluate the clinical and operational impacts of deploying POC MRI in emergency department (ED) and intensive care unit (ICU) patient settings for bedside neuroimaging, including the turnaround time. Materials and Methods In this preliminary retrospective study, all patients in the ED and ICU at a single academic medical center who underwent noncontrast brain MRI from January 2021 to June 2021 were investigated to determine the number of patients who underwent bedside POC MRI. Turnaround time, examination limitations, relevant findings, and potential CT and fixed MRI findings were recorded for patients who underwent POC MRI. Descriptive statistics were used to describe clinical variables. The Mann-Whitney U test was used to compare the turnaround time between POC MRI and fixed MRI examinations. Results Of 638 noncontrast brain MRI examinations, 36 POC MRI examinations were performed in 35 patients (median age, 66 years [IQR, 57-77 years]; 21 women), with one patient undergoing two POC MRI examinations. Of the 36 POC MRI examinations, 13 (36%) occurred in the ED and 23 (64%) in the ICU. There were 12 of 36 (33%) POC MRI examinations interpreted as negative, 14 of 36 (39%) with clinically significant imaging findings, and 10 of 36 (28%) deemed nondiagnostic for reasons such as patient motion. Of 23 diagnostic POC MRI examinations with comparison CT available, three (13%) demonstrated acute infarctions not apparent on CT scans. Of seven diagnostic POC MRI examinations with subsequent fixed MRI examinations, two (29%) demonstrated missed versus interval subcentimeter infarctions, while the remaining demonstrated no change. The median turnaround time of POC MRI was 3.4 hours in the ED and 5.3 hours in the ICU. Conclusion Point-of-care (POC) MRI was performed rapidly in the emergency department and intensive care unit. A few POC MRI examinations demonstrated acute infarctions not apparent at standard-of-care CT examinations. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Anzai and Moy in this issue.

Blood Pressure and Spot Sign in Spontaneous Supratentorial Subcortical Intracerebral Hemorrhage.

BACKGROUND: Spontaneous intracerebral hemorrhage is a potentially devastating cause of brain injury, often occurring secondary to hypertension. Contrast extravasation on computed tomography angiography (CTA), known as the spot sign, has been shown to predict hematoma expansion and worse outcomes. Although hypertension has been associated with an increased rate of the spot sign being present, the relationship between spot sign and blood pressure has not been fully explored. METHODS: We retrospectively analyzed data from 134 patients (40 women and 94 men, mean age 62.3 ± 15.73 years) presenting to a tertiary academic medical center with spontaneous supratentorial subcortical intracerebral hemorrhage from 1/1/2018 to 1/4/2021. RESULTS: A spot sign was demonstrated in images of 18 patients (13.43%) and correlated with a higher intracerebral hemorrhage score (2.61 ± 1.42 vs. 1.31 ± 1.25, p = 0.002), larger hematoma volume (53.49cm3 ± 32.08 vs. 23.45cm3 ± 25.65, p = 0.001), lower Glasgow Coma Scale on arrival (9.06 ± 4.56 vs. 11.74 ± 3.65, p = 0.027), increased risk of hematoma expansion (16.67% vs. 5.26%, p = 0.042), and need for surgical intervention (66.67% vs. 15.52%, p < 0.001). We did not see a correlation with age, sex, or underlying comorbidities. The presence of spot sign correlated with higher modified Rankin scores at discharge (4.94 ± 1.00 vs. 3.92 ± 1.64, p < 0.001). We saw significantly higher systolic blood pressure at the time of CTA in patients with a spot sign (184 mm Hg ± 43.11 vs. 153 mm Hg ± 36.99, p = 0.009) and the highest recorded blood pressure (p = 0.019), although not blood pressure on arrival (p = 0.081). Performing CTA early in the process of blood pressure lowering was associated with a spot sign (p < 0.001). CONCLUSIONS: The presence of spot sign correlates with larger hematomas, worse outcomes, and increased surgical intervention. There is a significant association between spot sign and systolic blood pressure at the time of CTA, with the highest systolic blood pressure being recorded prior to CTA. Although the role of intensive blood pressure management in spontaneous intracerebral hemorrhage remains a subject of debate, patients with a spot sign may be a subgroup that could benefit from this.

Tomato yellow leaf curl virus intergenic siRNAs target a host long noncoding RNA to modulate disease symptoms.

Tomato yellow leaf curl virus (TYLCV) and its related begomoviruses cause fast-spreading diseases in tomato worldwide. How this virus induces diseases remains largely unclear. Here we report a noncoding RNA-mediated model to elucidate the molecular mechanisms of TYLCV-tomato interaction and disease development. The circular ssDNA genome of TYLCV contains a noncoding intergenic region (IR), which is known to mediate viral DNA replication and transcription in host cells, but has not been reported to contribute directly to viral disease development. We demonstrate that the IR is transcribed in dual orientations during plant infection and confers abnormal phenotypes in tomato independently of protein-coding regions of the viral genome. We show that the IR sequence has a 25-nt segment that is almost perfectly complementary to a long noncoding RNA (lncRNA, designated as SlLNR1) in TYLCV-susceptible tomato cultivars but not in resistant cultivars which contains a 14-nt deletion in the 25-nt region. Consequently, we show that viral small-interfering RNAs (vsRNAs) derived from the 25-nt IR sequence induces silencing of SlLNR1 in susceptible tomato plants but not resistant plants, and this SlLNR1 downregulation is associated with stunted and curled leaf phenotypes reminiscent of TYLCV symptoms. These results suggest that the lncRNA interacts with the IR-derived vsRNAs to control disease development during TYLCV infection. Consistent with its possible function in virus disease development, over-expression of SlLNR1 in tomato reduces the accumulation of TYLCV. Furthermore, gene silencing of the SlLNR1 in the tomato plants induced TYLCV-like leaf phenotypes without viral infection. Our results uncover a previously unknown interaction between vsRNAs and host lncRNA, and provide a plausible model for TYLCV-induced diseases and host antiviral immunity, which would help to develop effective strategies for the control of this important viral pathogen.

Quantitative Pupillometry in the Intensive Care Unit.

Quantitative pupillometry provides a noninvasive and objective assessment within the neurological examination. This review details the physiology of the pupillary light response, the clinical significance of changes in pupillary reactivity, and the variables that compose the Neurological Pupil index or NPi are discussed. This article reviews the most recent applications and advances in quantitative pupillometry for noninvasive intracranial pressure monitoring, postcardiac arrest prognostication, and subarachnoid hemorrhage. Also discussed are the limitations and confounders of quantitative pupillometry in the modern neurological intensive care unit.

Electroencephalography Might Improve Diagnosis of Acute Stroke and Large Vessel Occlusion.

BACKGROUND AND PURPOSE: Clinical methods have incomplete diagnostic value for early diagnosis of acute stroke and large vessel occlusion (LVO). Electroencephalography is rapidly sensitive to brain ischemia. This study examined the diagnostic utility of electroencephalography for acute stroke/transient ischemic attack (TIA) and for LVO. METHODS: Patients (n=100) with suspected acute stroke in an emergency department underwent clinical exam then electroencephalography using a dry-electrode system. Four models classified patients, first as acute stroke/TIA or not, then as acute stroke with LVO or not: (1) clinical data, (2) electroencephalography data, (3) clinical+electroencephalography data using logistic regression, and (4) clinical+electroencephalography data using a deep learning neural network. Each model used a training set of 60 randomly selected patients, then was validated in an independent cohort of 40 new patients. RESULTS: Of 100 patients, 63 had a stroke (43 ischemic/7 hemorrhagic) or TIA (13). For classifying patients as stroke/TIA or not, the clinical data model had area under the curve=62.3, whereas clinical+electroencephalography using deep learning neural network model had area under the curve=87.8. Results were comparable for classifying patients as stroke with LVO or not. CONCLUSIONS: Adding electroencephalography data to clinical measures improves diagnosis of acute stroke/TIA and of acute stroke with LVO. Rapid acquisition of dry-lead electroencephalography is feasible in the emergency department and merits prehospital evaluation.

Language disparity is not a significant barrier for time-sensitive care of acute ischemic stroke.

BACKGROUND: Language barriers were reported to affect timely access to health care and outcome. The aim of this study was to investigate the effect of language disparity on quality benchmarks of acute ischemic stroke therapy. METHODS: Consecutive patients with acute ischemic stroke at the University of California Irvine Medical Center from 2013 to 2016 were studied. Patients were categorized into 3 groups according to their preferred language: English, Spanish, and other languages. Quality benchmarks and outcomes of the 3 language groups were analyzed. RESULTS: Of the 928 admissions, 69.7% patients recorded English as preferred language, as compared to 17.3% Spanish and 13.0% other languages. There was no significant difference in the rate of receiving intravenous thrombolysis (24.3, 22.1 and 21.0%), last-known-well to door time, door-to-imaging time, door-to-needle time, and hospital length of stay among the 3 language groups. In univariate analysis, the other languages group had lower chance of favorable outcomes than the English-speaking group (26.3% vs 40.4, p < 0.05) while the Spanish-speaking group had lower mortality rate than English-speaking group (3.1% vs 7.7%, p = 0.05). After adjusting for age and initial NIHSS scores, multivariate regression models showed no significant difference in favorable outcomes and mortality between different language groups. CONCLUSION: We demonstrate no significant difference in quality benchmarks and outcome of acute ischemic stroke among 3 different language groups. Our results suggest that limited English proficiency is not a significant barrier for time-sensitive stroke care at Comprehensive Stroke Center.

Intracerebral hemorrhage: who gets tested for methamphetamine use and why might it matter?

BACKGROUND: Methamphetamine use is an emerging risk factor for intracerebral hemorrhage (ICH). The aim of this study was to investigate the use of urine drug screen (UDS) for identifying methamphetamine-associated ICH. METHODS: This is a retrospective, single-center study of consecutive patients hospitalized with spontaneous ICH from January 2013 to December 2017. Patients were divided into groups based on presence of UDS. The characteristics of patients with and without UDS were compared. Factors associated with getting UDS were explored using multivariable analyses. RESULTS: Five hundred ninety-six patients with ICH were included. UDS was performed in 357 (60%), and positive for methamphetamine in 44 (12.3%). In contrast, only 19 of the 357 patients (5.3%) had a documented history of methamphetamine use. Multivariable analysis demonstrated that patients screened with UDS were more likely to be younger than 45 (OR, 2.24; 95% CI, 0.26-0.78; p = 0.004), male (OR, 1.65; 95% CI, 0.44-0.84; p = 0.003), smokers (OR, 1.74; 95% CI, 1.09-2.77; p <  0.001), with history of methamphetamine use (OR, 10.48; 95% CI, 2.48-44.34; p <  0.001), without diabetes (OR 1.47; 95% CI, 0.471-0.975; p = 0.036), not on anticoagulant (OR, 2.20; 95% CI, 0.26-0.78; p = 0.004), with National Institutes of Health Stroke Scale (NIHSS) > 4 (OR, 1.92; 95%CI, 1.34-2.75; p <  0.001), or require external ventricular drain (EVD) (OR, 1.63; 95%CI, 1.07-2.47; p = 0.021. There was no significant difference in race (p = 0.319). Reported history of methamphetamine use was the strongest predictor of obtaining a UDS (OR,10.48). Five percent of patients without UDS admitted history of use. CONCLUSION: UDS identified 12.3% of ICH patients with methamphetamine use as compared to 5.3% per documented history of drug use. There was no racial bias in ordering UDS. However, it was more often ordered in younger, male, smokers, with history of methamphetamine use, without diabetes or anticoagulant use.

Early Initiation of Oral Antihypertensives Reduces Intensive Care Unit Stay and Hospital Cost for Patients with Hypertensive Intracerebral Hemorrhage.

BACKGROUND/OBJECTIVE: Intravenous nicardipine infusion is effective for rapid blood pressure control. However, its use requires hemodynamic monitoring in the intensive care unit (ICU) and is associated with high hospital cost. This study aimed to examine the effect of early versus late initiation of oral antihypertensives on ICU length of stay (LOS) and cost of hospitalization in patients with hypertensive intracerebral hemorrhage (ICH). METHODS: This is a single-center retrospective study of patients with hypertensive ICH treated with nicardipine infusion from January 1, 2013, to December 31, 2017. Patients were dichotomized into study and control groups, based on receiving oral antihypertensives within 24 h versus after 24 h of emergency department arrival. Baseline characteristics, duration of nicardipine infusion, LOS in the ICU and hospital, functional outcome at discharge, and hospital cost were compared between the two groups using univariate and multivariate analysis. RESULTS: A total of 90 patients in the study group and 76 in the control group were identified. There was no significant difference in demographics, past medical history, and initial SBP between the two groups. After adjusting for confounding factors with multivariate regression models, early initiation of oral antihypertensives was associated with significant reductions in duration of nicardipine infusion (55.5 ± 60.1 vs 121.6 ± 141.3 h, p <0.005), nicardipine cost ($14,207 vs $29,299, p < 0.01), ICU LOS (2 vs 5 days, p < 0.005), and cost of hospitalization ($24,564 vs $47,366, p < 0.01). There was no significant difference in adversary renal events, favorable outcomes, and mortality between the two groups. CONCLUSIONS: Early initiation of oral antihypertensives is safe and may have a significant financial impact on patients with hypertensive ICH.

WEAVE Trial: Final Results in 152 On-Label Patients.

Background and Purpose- The WEAVE trial (Wingspan Stent System Post Market Surveillance) is a postmarket surveillance trial mandated by the Food and Drug Administration to assess the periprocedural safety of the Wingspan Stent system in the treatment of symptomatic intracranial atherosclerotic disease. Methods- A total of 152 consecutive patients who met the Food and Drug Administration on-label usage criteria were enrolled at 24 hospitals and underwent angioplasty and stenting with the Wingspan stent. On-label criteria included age 22 to 80 years, symptomatic intracranial atherosclerotic stenosis of 70% to 99%, baseline modified Rankin Scale score ≤3, ≥2 strokes in the vascular territory of the stenotic lesion with at least 1 stroke while on medical therapy, and stenting of the lesion ≥8 days after the last stroke. The primary analysis assessed the periprocedural stroke, bleed, and death rate within 72 hours of the procedure with adjudication by a core study Stroke Neurologist. Results- The trial was stopped early after interim analysis of 152 consecutive patients demonstrated a lower than expected 2.6% (4/152 patients) periprocedural stroke, bleed, and death rate. This was lower than the 4% periprocedural primary event safety benchmark set for the interim analysis in the study. A total of 97.4% (148/152) patients were event-free at 72 hours, 1.3% (2/152) had nonfatal strokes, and 1.3% (2/152) of patients died. Conclusions- With experienced interventionalists, and proper patient selection following the on-label usage guidelines, the use of the Wingspan stent for intracranial atherosclerotic disease demonstrated a low periprocedural complication rate and excellent safety profile. This is the largest on-label, multicenter, prospective trial of the Wingspan stent system to date with the lowest reported complication rate. Clinical Trial Registration- URL: https://www.clinicaltrials.gov . Unique identifier: NCT02034058.

Three easily-implementable changes reduce median door-to-needle time for intravenous thrombolysis by 23 minutes.

BACKGROUND: The benefit of intravenous thrombolysis (IVT) for acute ischemic stroke is time dependent. Despite great effort, the median door-to-needle time (DNT) was 60 min at the United States stroke centers. We investigated the effect of a simple quality improvement initiative on DNT for IVT. METHODS: This is a single-center study of patients treated with IVT between 2013 and 2017. A simple quality improvement initiative was implemented in January 2015 to allow the Stroke team to manage hypertension in the emergency room, to make decision for IVT before getting blood test results unless patients were taking oral anticoagulants, and to give IVT in the CT suite. Baseline characteristics, DNT and outcomes at hospital discharge were compared between pre- and post-intervention groups. RESULTS: Ninety and 136 patients were treated with IVT in pre- and post-intervention groups, respectively. The rate of IVT was significantly higher in the post-intervention group (20% vs. 14.4%, p = 0.007). The median DNT with interquartile range (IQR) was reduced significantly by 23 min (63[53-81] vs. 40[29-53], p < 0.001) with more patients in the post-intervention group receiving IVT within 60 min (81.6% vs. 46.7%) and 45 min (64.0% vs.17.8%). There was no significant difference in symptomatic intracerebral hemorrhage rate (1.5% vs. 1.1%), modified Rankin Scale 0-1 (29.4% vs. 23.3%), and hospital mortality (7.4% vs. 6.7%) between the 2 groups. CONCLUSIONS: Three easily-implementable quality improvement initiative increases IVT rate and reduces DNT significantly without increasing the rate of IVT-related complications in our comprehensive stroke center.

Electroencephalography Measures are Useful for Identifying Large Acute Ischemic Stroke in the Emergency Department.

BACKGROUND: Early diagnosis of stroke optimizes reperfusion therapies, but behavioral measures have incomplete accuracy. Electroencephalogram (EEG) has high sensitivity for immediately detecting brain ischemia. This pilot study aimed to evaluate feasibility and utility of EEG for identifying patients with a large acute ischemic stroke during Emergency Department (ED) evaluation, as these data might be useful in the prehospital setting. METHODS: A 3-minute resting EEG was recorded using a dense-array (256-lead) system in patients with suspected acute stroke arriving at the ED of a US Comprehensive Stroke Center. RESULTS: An EEG was recorded in 24 subjects, 14 with acute cerebral ischemia (including 5 with large acute ischemic stroke) and 10 without acute cerebral ischemia. Median time from stroke onset to EEG was 6.6 hours; and from ED arrival to EEG, 1.9 hours. Delta band power (P = .004) and the alpha/delta frequency band ratio (P = .0006) each significantly distinguished patients with large acute ischemic stroke (n = 5) from all other patients with suspected stroke (n = 19), with the best diagnostic utility coming from contralesional hemisphere signals. Larger infarct volume correlated with higher EEG power in the alpha/delta frequency band ratio within both the ipsilesional (r = -0.64, P = .013) and the contralesional (r = -0.78, P = .001) hemispheres. CONCLUSIONS: Within hours of stroke onset, EEG measures (1) identify patients with large acute ischemic stroke and (2) correlate with infarct volume. These results suggest that EEG measures of brain function may be useful to improve diagnosis of large acute ischemic stroke in the ED, findings that might be useful to pre-hospital applications.

Evolution of a US County System for Acute Comprehensive Stroke Care.

BACKGROUND AND PURPOSE: In Orange County, California, patients with suspected acute stroke are taken to stroke neurology receiving centers that are designated by County Emergency Medical Services authorities as either hubs or spokes based on endovascular treatment capability. We examined relationships between stroke details, reperfusion therapies, hospital transfers, and their change over time. METHODS: All patients from January 1, 2013, to December 31, 2015, for whom 911 was called within 7 hours of onset in whom Emergency Medical Services personnel suspected acute stroke were evaluated. RESULTS: Among 6132 patients, 3924 (64%) had confirmed diagnosis of stroke (74% ischemic/26% hemorrhagic), yielding diagnostic precision of 64% in the field. Of the 2892 patients with acute ischemic stroke, acute reperfusion therapy was given to 29.2% (21.7% intravenous tPA [tissue-type plasminogen activator] only and 7.5% endovascular treatment). Rates of endovascular treatment of patients with ischemic stroke increased over time, more than doubling from 5.6% in 2013 to 12.5% (odds ratio per 3-month quarter=1.09; 95% confidence interval, 1.04-1.14; P<0.0001). Only 3.4% of patients with acute ischemic stroke were transferred from a spoke to a hub hospital; transfer rates were inversely related to age (P<0.0001), and reperfusion therapy rates did not vary according to transfer status. CONCLUSIONS: Favorable features of this acute stroke care system include reperfusion therapy in 29.2% of patients with ischemic stroke and substantial increases in endovascular treatment rates over time. Continued efforts to optimize acute stroke systems of care can be directed toward improving access to best acute stroke therapies.

Re-analysis of long non-coding RNAs and prediction of circRNAs reveal their novel roles in susceptible tomato following TYLCV infection.

BACKGROUND: Long Noncoding-RNAs (LncRNAs) are known to be involved in some biological processes, but their roles in plant-virus interactions remain largely unexplored. While circular RNAs (circRNAs) have been studied in animals, there has yet to be extensive research on them in a plant system, especially in tomato-tomato yellow leaf curl virus (TYLCV) interaction. RESULTS: In this study, RNA transcripts from the susceptible tomato line JS-CT-9210 either infected with TYLCV or untreated, were sequenced in a pair-end strand-specific manner using ribo-zero rRNA removal library method. A total of 2056 lncRNAs including 1767 long intergenic non-coding RNA (lincRNAs) and 289 long non-coding natural antisense transcripts (lncNATs) were obtained. The expression patterns in lncRNAs were similar in susceptible tomato plants between control check (CK) and TYLCV infected samples. Our analysis suggested that lncRNAs likely played a role in a variety of functions, including plant hormone signaling, protein processing in the endoplasmic reticulum, RNA transport, ribosome function, photosynthesis, glulathione metabolism, and plant-pathogen interactions. Using virus-induced gene silencing (VIGS) analysis, we found that reduced expression of the lncRNA S-slylnc0957 resulted in enhanced resistance to TYLCV in susceptible tomato plants. Moreover, we identified 184 circRNAs candidates using the CircRNA Identifier (CIRI) software, of which 32 circRNAs were specifically expressed in untreated samples and 83 circRNAs in TYLCV samples. Approximately 62% of these circRNAs were derived from exons. We validated the circRNAs by both PCR and Sanger sequencing using divergent primers, and found that most of circRNAs were derived from the exons of protein coding genes. The silencing of these circRNAs parent genes resulted in decreased TYLCV virus accumulation. CONCLUSION: In this study, we identified novel lncRNAs and circRNAs using bioinformatic approaches and showed that these RNAs function as negative regulators of TYLCV infection. Moreover, the expression patterns of lncRNAs in susceptible tomato plants were different from that of resistant tomato plants, while exonic circRNAs expression positively associated with their respective protein coding genes. This work provides a foundation for elaborating the novel roles of lncRNAs and circRNAs in susceptible tomatoes following TYLCV infection.

Drought stress had a predominant effect over heat stress on three tomato cultivars subjected to combined stress.

BACKGROUND: Abiotic stresses due to environmental factors could adversely affect the growth and development of crops. Among the abiotic stresses, drought and heat stress are two critical threats to crop growth and sustainable agriculture worldwide. Considering global climate change, incidence of combined drought and heat stress is likely to increase. The aim of this study was to shed light on plant growth performance and leaf physiology of three tomatoes cultivars ('Arvento', 'LA1994' and 'LA2093') under control, drought, heat and combined stress. RESULTS: Shoot fresh and dry weight, leaf area and relative water content of all cultivars significantly decreased under drought and combined stress as compared to control. The net photosynthesis and starch content were significantly lower under drought and combined stress than control in the three cultivars. Stomata and pore length of the three cultivars significantly decreased under drought and combined stress as compared to control. The tomato 'Arvento' was more affected by heat stress than 'LA1994' and 'LA2093' due to significant decreases in shoot dry weight, chlorophyll a and carotenoid content, starch content and NPQ (non-photochemical quenching) only in 'Arvento' under heat treatment. By comparison, the two heat-tolerant tomatoes were more affected by drought stress compared to 'Arvento' as shown by small stomatal and pore area, decreased sucrose content, ΦPSII (quantum yield of photosystem II), ETR (electron transport rate) and qL (fraction of open PSII centers) in 'LA1994' and 'LA2093'. The three cultivars showed similar response when subjected to the combination of drought and heat stress as shown by most physiological parameters, even though only 'LA1994' and 'LA2093' showed decreased Fv/Fm (maximum potential quantum efficiency of photosystem II), ΦPSII, ETR and qL under combined stress. CONCLUSIONS: The cultivars differing in heat sensitivity did not show difference in the combined stress sensitivity, indicating that selection for tomatoes with combined stress tolerance might not be correlated with the single stress tolerance. In this study, drought stress had a predominant effect on tomato over heat stress, which explained why simultaneous application of heat and drought revealed similar physiological responses to the drought stress. These results will uncover the difference and linkage between the physiological response of tomatoes to drought, heat and combined stress and be important for the selection and breeding of tolerant tomato cultivars under single and combine stress.

Genome-wide analysis of bHLH transcription factor and involvement in the infection by yellow leaf curl virus in tomato (Solanum lycopersicum).

BACKGROUND: The basic helix-loop-helix (bHLH) proteins are a superfamily of transcription factors that can bind to specific DNA target sites. They have been well characterized in model plants such as Arabidopsis and rice and have been shown to be important regulatory components in many different biological processes. However, no systemic analysis of the bHLH transcription factor family has yet been reported in tomatoes. Tomato yellow leaf curl virus (TYLCV) threatens tomato production worldwide by causing leaf yellowing, leaf curling, plant stunting and flower abscission. RESULTS: A total of 152 bHLH transcription factors were identified from the entire tomato genome. Phylogenetic analysis of bHLH domain sequences from Arabidopsis and tomato facilitated classification of these genes into 26 subfamilies. The evolutionary and possible functional relationships revealed during this analysis are supported by other criteria, including the chromosomal distribution of these genes, the conservation of motifs and exon/intron structural patterns, and the predicted DNA binding activities within subfamilies. Distribution mapping results showed bHLH genes were localized on the 12 tomato chromosomes. Among the 152 bHLH genes from the tomato genome, 96 bHLH genes were detected in the TYLCV-susceptible and resistant tomato breeding line before (0 dpi) and after TYLCV (357 dpi) infection. As anticipated, gene ontology (GO) analysis indicated that most bHLH genes are related to the regulation of macromolecule metabolic processes and gene expression. Only four bHLH genes were differentially expressed between 0 and 357 dpi. Virus-induced gene silencing (VIGS) of one bHLH genes SlybHLH131 in resistant lines can lead to the cell death. CONCLUSION: In the present study, 152 bHLH transcription factor genes were identified. One of which bHLH genes, SlybHLH131, was found to be involved in the TYLCV infection through qRT-PCR expression analysis and VIGS validation. The isolation and identification of these bHLH transcription factors facilitated clarification of the molecular genetic basis for the genetic improvement of tomatoes and the development of functional gene resources for transgenic research. In addition, these findings may aid in uncovering an unexplored mechanism during the TYLCV infection in tomatoes.

Functional conservation of the glycosyltransferase gene GT47A in the monocot rice.

Glucuronoarabinoxylan is the major hemicellulose in grass cell walls, yet the mechanism of xylan synthesis in monocot plants is still unclear. Unraveling the genes involved in the biosynthesis of xylan in rice will be very important for the utilization of rice straw as a source of bioenergy in the future. In this report, we investigated the functional role of a rice gene homologous to Arabidopsis IRREGULAR XYLEM10 (IRX10), belonging to the glycosyl transferase (GT) gene family 47 (GT47), in the biosynthesis of xylan. The protein sequence of OsGT47A from rice exhibits a 93.49% similarity to IRX10, which is involved in the biosynthesis of glucuronoxylan in Arabidopsis. Phylogenetic analysis of the GT47 glycosyl transferase family in the rice genome revealed that OsGT47A is a closely related homolog of IRX10 and IRX10L. Expression pattern analysis showed that the OsGT47A gene is highly expressed in the rice stem. Overexpression of OsGT47A in the irx10 irx10L double mutant rescued the plant growth phenotype and restored secondary wall thickness. Analysis of monosaccharides indicated that the rescued plants had levels of xylose identical to those of the wild type plants, and the fluorescence signals were restored in the complementation plants by xylan immunolocalization. The OsGT47A complementation under the native promoter of Arabidopsis IRX10L (ProIRX10L) partially rescued the double mutant, indicating that OsGT47A is functionally equivalent to IRX10L. Together, these results suggest that the IRX10 homolog OsGT47A exhibits functional conservation and is most likely involved in xylan synthesis in rice.

Unilateral pupillary mydriasis from nebulized ipratropium bromide: A false sign of brain herniation in the intensive care unit.

Although there are many causes of anisocoria in the intensive care setting, the development of unilateral mydriasis in patients with intracranial hemorrhage or tumor is a neurological emergency, as it may herald the onset of uncal herniation. We describe two patients with a hemiparesis from neurosurgical disorder who subsequently developed a fixed and dilated pupil. The pupillary abnormality was caused by nebulized ipratropium bromide in both cases, and resolved when the medication was discontinued. Nebulized ipratropium may leak from the mask into ipsilateral eye and cause mydriasis in patients with facial weakness. This benign cause of anisocoria in the intensive care setting is distinguished from uncal herniation by the laterality of neurologic findings, and lack of mental status change, ptosis, and extraocular movement impairment.

Cardiomyopathy in Patients With Acute Ischemic Stroke and Methamphetamine Use: Relevance for Cardioembolic Stroke and Outcome.

BACKGROUND: Methamphetamine use has emerged as a major risk factor for cardiovascular and cerebrovascular disease in young adults. The aim of this study was to investigate a possible association of methamphetamine use with cardioembolic stroke. METHODS AND RESULTS: We performed a retrospective study of patients with acute ischemic stroke admitted at our medical center between 2019 and 2022. All patients were screened for methamphetamine use and cardiomyopathy, defined as left ventricular ejection fraction ≤45%. Among 938 consecutive patients, 46 (4.9%) were identified as using methamphetamine. Compared with the nonmethamphetamine group (n=892), the methamphetamine group was significantly younger (52.8±9.6 versus 69.7±15.2 years; P<0.001), included more men (78.3% versus 52.8%; P<0.001), and had a significantly higher rate of cardiomyopathy (30.4% versus 14.0%; P<0.01). They were also less likely to have a history of atrial fibrillation (8.7% versus 33.4%; P<0.01) or hyperlipidemia (28.3% versus 51.7%; P<0.01). Compared with patients with cardiomyopathy without methamphetamine use, the patients with cardiomyopathy with methamphetamine use had significantly lower left ventricular ejection fraction (26.0±9.59% versus 32.47±9.52%; P<0.01) but better functional outcome at 3 months, likely attributable to significantly younger age and fewer comorbidities. In the logistic regression model of clinical variables, methamphetamine-associated cardiomyopathy was found to be significantly associated with cardioembolic stroke (odds ratio, 1.79 [95% CI, 1.04-3.06]; P<0.05). CONCLUSIONS: We demonstrate that methamphetamine use is significantly associated with cardiomyopathy and cardioembolic stroke in young adults.