High myopia at high altitudes.

Background: Optic nerve sheath diameter (ONSD) increases significantly at high altitudes, and is associated with the presence and severity of acute mountain sickness (AMS). Exposure to hypobaria, hypoxia, and coldness when hiking also impacts intraocular pressure (IOP). To date, little is known about ocular physiological responses in trekkers with myopia at high altitudes. This study aimed to determine changes in the ONSD and IOP between participants with and without high myopia (HM) during hiking and to test whether these changes could predict symptoms of AMS. Methods: Nine participants with HM and 18 without HM participated in a 3-day trek of Xue Mountain. The ONSD, IOP, and questionnaires were examined before and during the trek of Xue Mountain. Results: The ONSD values increased significantly in both HM (p = 0.005) and non-HM trekkers (p = 0.018) at an altitude of 1,700 m. In the HM group, IOP levels were greater than those in the non-HM group (p = 0.034) on the first day of trekking (altitude: 3,150 m). No statistically significant difference was observed between the two groups for the values of ONSD. Fractional changes in ONSD at an altitude of 1,700 m were related to the development of AMS (r pb = 0.448, p = 0.019) and the presence of headache symptoms (r pb = 0.542, p = 0.004). The area under the ROC curve for the diagnostic performance of ONSD fractional changes at an altitude of 1,700 m was 0.859 for predicting the development of AMS and 0.803 for predicting the presence of headache symptoms. Conclusion: Analysis of changes in ONSD at moderate altitude could predict AMS symptoms before an ascent to high altitude. Myopia may impact physiological accommodation at high altitudes, and HM trekkers potentially demonstrate suboptimal regulation of aqueous humor in such environments.

A pilot study of digital bedside cards in the emergency room of a medical centre in Taiwan.

The emergency room (ER) digital bedside card is a simple and important invention. It can be directly connected to the hospital information system to display important patient information in real time, reduce the workload of ER staff, improve their satisfaction, and provide useful information for patients and their families. We conducted a prospective study of ER staff using questionnaires and conducted Wilcoxon signed-rank test to compare before and after ER digital bedside card implementation in the Tamsui MacKay Memorial Hospital. Sixty participants of the ER staff joined the study before and after digital card implementation. After the ER digital bedside card was set up, the number of round trips from the nursing station to the ER bedside and the number of common questions asked by patients and their family members were significantly reduced. The cards reduced the response time for frequently asked questions by patients and their family members and significantly improved the satisfaction of ER staff. Our study showed that ER digital bedside cards reduced the workload of ER staff, provided patients and their families with useful information, and greatly improved ER staff satisfaction. This marks an important milestone in the future development of smart ER.

The changes of electroencephalography in mountaineers on Mount Jade, Taiwan: An observational study.

BACKGROUND: The diagnosis of acute mountain sickness, which lacks a reliable and objective diagnostic tool, still depends on the clinical symptoms and signs and remains a major threat and unpredictable disease affecting millions of mountaineers. OBJECTIVES: To record electroencephalography signals with small, convenient, wireless equipment and to test whether electroencephalography parameters, which are more sensitive and reliable markers, could predict the symptoms of acute mountain sickness. METHODS: Twenty-five participants were enrolled and separated into two groups to climb Mount Jade in Taiwan. We collected electrocardiography signals and arterial oxygen saturation data at ground, moderate (2,400 m), and high altitude (3,400 m). A spectral analysis of the electrocardiography was performed to assess the study subjects' electroencephalography activity at different frequencies (α, ß, θ, δ) and the mean power frequency of electrocardiography. The clinical symptoms and Lake Louise Acute Mountain Sickness scores of the subjects were recorded for comparison. RESULTS: A significant change in the δ power of electroencephalography was recorded in subjects ascending from the ground to a high altitude of 3,400 m in a 4-day itinerary. In addition, between the two groups of subjects with and without acute mountain sickness (Lake Louise Acute Mountain Sickness scores < 3 and ≥ 3), the δ power of electroencephalography at the fronto-parietal 1 and parietal 3 electrodes at moderate altitude as well as the changes of δ power and mean power frequency of electrocardiography over parietal 4 at high altitude showed a significant difference. At moderate altitude, the increasing δ power of electroencephalography at the parietal 4 electrode was related to the headache symptom of acute mountain sickness before ascending to high altitude. CONCLUSION: At moderate altitude, the δ power increase of electroencephalography at the P4 electrode could be a predictor of acute mountain sickness symptoms before ascending to high altitude. Thus, electroencephalography had the potential to identify the risk of acute mountain sickness.

Visual hallucinations in 246-km mountain ultra-marathoners: An observational study.

Ultra-marathons are typically held over harsh terrains such as mountains, deserts, or other wilderness, and place severe demands on the physical and psychological capabilities of participants. Adventure-race competitors commonly report hallucinations. The goal of this study was to gain insight into visual hallucinations (VHs) during a mountain ultra-marathon. Thirty-one Taiwanese runners who participated in the 2018 Run Across Taiwan Ultra-Marathon, which spans 246 km with an altitude difference of 3266 m and an overall cut-off time of 44 h, volunteered for this study. Self-reported questionnaires on sleep duration, hallucinatory experiences, clinical symptoms of cold- and heat-related illnesses, and the 2018 Lake Louise Acute Mountain Sickness (AMS) Score were recorded prerace, during the summit, immediately postrace, and 3-days postrace. Hematological samples were collected 1 week before, immediately after, and 3 days after the race. Eight ultra-marathoners (six males and two females; seven finishers and one withdrawer) were recruited. Three out of eight (37.5%) subjects (two males and one female) reported experiencing VHs during the last 60 km. Three out of five (60%) lower-ranked subjects experienced VHs. All eight runners slept for <30 min during the race. None of the runners presented with headache either during or after the race to meet the criteria for AMS. None of the runners suffered an abnormal thermoregulatory response or a hypoglycemic episode throughout the ultra-marathon. The changes in blood osmolality immediately postrace were subclinical, despite being statistically significant. Among the three runners with VHs, none presented with severe dehydration or dysnatremia immediately postrace. High-altitude exposure, hyper/hypothermia, dehydration, dysnatermia, or hypoglycemia did not seem to contribute to hallucination onset in our subjects during the event. VHs of ultra-marathoners may be associated with excessive physical exertion and sleep deprivation.

Genomic Features of Open Chromatin Regions (OCRs) in Wild Soybean and Their Effects on Gene Expressions.

Transcription activation is tightly associated with the openness of chromatin, which allows direct contact between transcriptional regulators, such as transcription factors, and their targeted DNA for downstream gene activation. However, the annotation of open chromatin regions (OCRs) in the wild soybean (Glycine soja) genome is limited. We performed assay for transposase-accessible chromatin using sequencing (ATAC-seq) and successfully identified 22,333 OCRs in the leaf of W05 (a wild soybean accession). These OCRs were enriched in gene transcription start sites (TSS) and were positively correlated with downstream gene expression. Several known transcription factor (TF)-binding motifs were also enriched at the OCRs. A potential regulatory network was constructed using these transcription factors and the OCR-marked genes. Furthermore, by overlapping the OCR distribution with those of histone modifications from chromatin immunoprecipitation followed by sequencing (ChIP-seq), we found that the distribution of the activation histone mark, H3K4me3, but not that of the repressive H3K27me3 mark, was closely associated with OCRs for gene activation. Several putative enhancer-like distal OCRs were also found to overlap with LincRNA-encoding loci. Moreover, our data suggest that homologous OCRs could potentially influence homologous gene expression. Hence, the duplication of OCRs might be essential for plant genome architecture as well as for regulating gene expression.

Risk factors for acute kidney injury in the elderly undergoing contrast-enhanced computed tomography in the emergency department.

BACKGROUND: There have been few studies focusing on the incidence and risk factors for elderly patients undergoing computed tomography (CT) scans with intravascular contrast medium, who develop contrast-induced nephropathy (CIN) in the emergency department (ED). Our objective was to investigate the incidence of and risk factors for, CIN in elderly patients seen in the ED, who receive intravenous contrast media for CT examination. METHODS: Patients ≥65 years of age who received contrast-enhanced CT were eligible for inclusion in this retrospective analysis. CIN was defined as an increase in serum creatinine (sCr) ≥0.5 mg/dL 48 to 72 hours after intravenous contrast administration. Multiple logistic regression analysis for risk factors for CIN and Chi-square test were performed for trend analysis for CIN incidence and mortality of different risk scores. RESULTS: A total of 594 patients, with a mean age of 79.8 ± 6.8 years were included. The overall incidence of CIN was 8.6%. In multivariate analyses, CIN was associated with diabetes mellitus [adjusted odds ratio (OR) = 1.93; 95% confidence interval (CI) = 1.04-3.62], precontrast sCr >1.5 mg/dL (OR = 2.72; 95% CI = 1.44-5.13), and acute hypotension (OR = 3.56; 95% CI = 1.29-9.84). CIN and mortality increased with increasing risk score (p < 0.001 and p = 0.001, respectively). The all-cause in-hospital mortality rate was 13.1%, and the mortality rates for patients with and without CIN (p < 0.001) were 47.1% and 9.9%, respectively. CONCLUSION: Our investigation confirmed diabetes mellitus, precontrast sCr >1.5 mg/dL and acute hypotension as risk factors for CIN, and also developed a simple risk score for elderly patients seen in the ED.

N-acetylcysteine for the prevention of contrast-induced nephropathy in the emergency department.

OBJECTIVE: To evaluate the use of N-acetylcysteine (NAC), a potent antioxidant, to prevent contrast-induced nephropathy (CIN). METHODS: We prospectively studied 209 patients (106 in the NAC group and 103 in the control group) who received contrast-enhanced computed tomography (CECT) in the emergency department (ED). The NAC group received intravenous NAC (600 mg) before CECT imaging to prevent CIN. Both the NAC and control groups were treated using a standardized hydration strategy, where clinically feasible. RESULTS: The patients' mean age was 79.6±9.8 years. The prevalence of hypertension, diabetes, and chronic kidney disease (CKD) were 63.2%, 27.3%, and 21.5%, respectively. The baseline clinical characteristics were similar between the two groups except for their body weight (p=0.011), amount of contrast material administered (p=0.049) and prevalence of CKD (p=0.002). The incidence of CIN was 7.5% in the NAC group and 14.6% in the control group. The adjusted odds ratio was 0.305 (95% confidence interval: 0.097 to 0.960, p=0.042). All-cause mortality was 7.5% in the NAC group and 12.6% in the control group, which was not significantly different. Temporary hemodialysis was required in 0% of subjects in the NAC group and 1.0% in the control group, which was not a statistically significant difference. CONCLUSION: A single dose of NAC before CECT imaging can prevent CIN in an ED setting. However, it does not improve the mortality rate or the need for dialysis.

D-dimer in patients with suspected acute mesenteric ischemia.

OBJECTIVES: The aims of this study were to assess the diagnostic value of D-dimer in patients with suspected acute mesenteric ischemia (AMI) and to evaluate the correlation between D-dimer levels and the severity of bowel necrosis. METHODS: A prospective, noninterventional study of 67 patients with clinical suspicion of AMI was performed. Measurement of D-dimer levels was performed using a latex turbidimetric method. RESULTS: Acute mesenteric ischemia was diagnosed in 23 patients (34.3%) and non-AMI in 44 patients (65.7%). Median D-dimer levels on admission were 6.24 microg fibrinogen equivalent units (FEU)/mL (range, 0.96-53.48 microg FEU/mL) in patients with AMI and 3.45 microg FEU/mL (range, 0.50-44.69 microg FEU/mL) in non-AMI patients (P = .064). D-dimer had poor discriminative value to differentiate the presence from the absence of AMI with an area under the receiver operating characteristic curve of 0.64 (95% confidence interval, 0.50-0.78). A serum D-dimer cutoff value of 1.0 microg FEU/mL had a sensitivity of 96%, a specificity of 18%, a positive likelihood ratio of 1.17, and a negative likelihood ratio of 0.24. Among patients with AMI verified at operation, 8 had resectable bowl necrosis and 9 had unresectable bowel necrosis. There was no difference in serum D-dimer levels between resectable and unresectable bowel necrosis (P = .665). CONCLUSIONS: Detection of serum D-dimer could not help to differentiate patient with AMI from those with non-AMI. We did not find a correlation between serum D-dimer levels and the severity of AMI. However, measurement of D-dimer levels can be of value for a small decrease in the likelihood of AMI, when the result is low.

Impending aneurysm rupture after endovascular repair of infrarenal abdominal aortic aneurysm.

An 81-year-old male presented with lower abdominal pain radiating to back associated with diaphoresis. He received endovascular repair of an infrarenal abdominal aortic aneurysm 21 months ago. Triple phase abdominal CT showed impending aneurysm rupture secondary to endoleak. After re-stenting and percutaneous transluminal angioplasty, he had an uneventful recovery later.