Selective poly(vinyl ether) upcycling via photooxidative degradation with visible light.

Poly(vinyl ethers) (PVEs) have many applications, such as adhesives, lubricants, and anticorrosive agents, thanks to their elastic, nonirritating, and chemically inert properties. The recycling of PVEs remains largely underexplored, and current methods lack generality towards other polymer classes. Thus, the chemical upcycling of PVE into small molecule feedstocks would provide an alternative approach to combat these current issues. Here, we report a visible light-mediated method of upcycling poly(isobutyl vinyl ether) (PIBVE) into small molecules via photooxidative degradation using chlorine or bromine radicals. PIBVE can be degraded to low molecular weight oligomers within 2 h, producing good yields of alcohols, aldehydes, and carboxylic acids. Mechanistic studies suggest that hydrogen atom transfer (HAT) from the backbone or the side chain leads to small molecule generation via oxidative cleavages. Additionally, this protocol was applied to a copolymer of poly(methyl acrylate-co-isobutyl vinyl ether) to demonstrate the preference for the degradation of polymers bearing more electron-rich C-H bonds through a judicious choice of abstraction agent. Ultimately, we show that photooxidative degradation enables the selective chemical upcycling of PVEs as a method of plastic waste valorization.

Selective Electrocatalytic Degradation of Ether-Containing Polymers.

Leveraging electrochemistry to degrade robust polymeric materials has the potential to impact society's growing issue of plastic waste. Herein, we develop an electrocatalytic oxidative degradation of polyethers and poly(vinyl ethers) via electrochemically mediated hydrogen atom transfer (HAT) followed by oxidative polymer degradation promoted by molecular oxygen. We investigated the selectivity and efficiency of this method, finding our conditions to be highly selective for polymers with hydridic, electron-rich C-H bonds. We leveraged this reactivity to degrade polyethers and poly(vinyl ethers) in the presence of polymethacrylates and polyacrylates with complete selectivity. Furthermore, this method made polyacrylates degradable by incorporation of ether units into the polymer backbone. We quantified degradation products, identifying up to 36 mol % of defined oxidation products, including acetic acid, formic acid, and acetaldehyde, and we extended this method to degrade a polyether-based polyurethane in a green solvent. This work demonstrates a facile, electrochemically-driven route to degrade polymers containing ether functionalities.

Neurofeedback and Affect Regulation Circuitry in Depressed and Healthy Adolescents.

Neurodevelopmental psychopathology seeks to understand higher-order emotion regulation circuitry to develop new therapies for adolescents with depression. Depressed (N = 34) and healthy youth (N = 19) completed neurofeedback (NF) training and exhibited increased bilateral amygdala and hippocampus activity in the region of interest (ROI) analyses by recalling positive autobiographical memories. We tested factors supportive of the engagement of emotion regulation's neural areas during NF (i.e., parental support, medication, and gender effects upon anterior cingulate cortex (ACC) engagement). Whole-brain analyses yielded effects of NF vs. control condition and effects of diagnosis. Youth showed higher amygdala and hippocampus (AMYHIPPO) activity during the NF vs. control condition, particularly in the left hippocampus. ACC's activity was also higher during NF vs. control. Higher average ACC activity was linked to better parental support, absent depression, female gender, and absent medication. Control youth showed higher average AMYHIPPO and ACC activity throughout the task and a faster decline in activity vs. depressed youths. Whole-brain level analyses showed higher activity in the frontotemporal network during the NF vs. control conditions, suggesting targeting their connectivity in future neurofeedback trials.

Exogenous preculture with sucrose and abscisic acid improves post-cryopreservation survival of eastern bracken fern gametophytes.

Cryopreservation is an important technique used in the conservation of various plant tissues. This study proposes a cryopreservation method for the long-term conservation of eastern bracken fern gametophytes (Pteridium aquilinum var. latiusculum). Encapsulation-dehydration of the gametophytes was performed, and the exogenous sucrose and abscisic acid (ABA) preculture conditions were investigated. Gametophytes are sensitive to dehydration and drying, and the following treatment conditions were applied: encapsulation by alginate containing 0.75 M sucrose, 18-h loading treatment with 0.75 M sucrose, and 6-h drying treatment. The survival rate following cryopreservation was determined. The water content of < 27.5% in the alginate beads after dehydration and drying was found to be appropriate for ensuring survival. Additionally, performing an exogenous sucrose and ABA preculture was essential before encapsulation to achieve a survival of ≥ 90%. The high stress induced by cryopreservation and exogenous preculture regulated the expression of PaSuSy, PaLEA14, and PaABI1b and the endogenous ABA content. In eastern bracken gametophytes, ABI1 appears to be a negative regulator of ABA signaling. These results indicate that the encapsulation-dehydration method is effective for the long-term conservation of eastern bracken fern gametophytes, and exogenous preculture alleviates abiotic stress and increases the survival rate.

Association between Consumption of Dietary Supplements and Chronic Kidney Disease Prevalence: Results of the Korean Nationwide Population-Based Survey.

Despite the enormous global market of dietary supplements, the impact of dietary supplements on kidney disease is still unclear. Based on the National Health and Nutrition Examination Survey from 2015 to 2017, this study evaluated the association between dietary supplement and chronic kidney disease (CKD) in 13,271 Korean adults. Among the dietary supplements, vitamin and mineral intake was the highest at 61.41%, followed by omega-3 fatty acids at 11.85%, and ginseng at 7.99%. The prevalence of CKD was significantly higher in those who consumed amino acids and proteins, ginseng and red ginseng, and herbal medicine (plant extract)-berries than in those who did not. Conversely, patients who consumed probiotic supplements had a significantly lower prevalence of CKD than those who did not. In the population without CKD risk factors or history of CKD, the prevalence of CKD was high in the group consuming ginseng and red ginseng. After adjusting for covariates, the herbal medicine (plant extract)-berry group showed an independent association with CKD incidence. In conclusion, it is suggested that dietary supplements may affect kidney function. Further large-scale cohort studies are required to elucidate the exact effects of each dietary supplement on CKD.

Audiovisual integration in the human brain: a coordinate-based meta-analysis.

People can seamlessly integrate a vast array of information from what they see and hear in the noisy and uncertain world. However, the neural underpinnings of audiovisual integration continue to be a topic of debate. Using strict inclusion criteria, we performed an activation likelihood estimation meta-analysis on 121 neuroimaging experiments with a total of 2,092 participants. We found that audiovisual integration is linked with the coexistence of multiple integration sites, including early cortical, subcortical, and higher association areas. Although activity was consistently found within the superior temporal cortex, different portions of this cortical region were identified depending on the analytical contrast used, complexity of the stimuli, and modality within which attention was directed. The context-dependent neural activity related to audiovisual integration suggests a flexible rather than fixed neural pathway for audiovisual integration. Together, our findings highlight a flexible multiple pathways model for audiovisual integration, with superior temporal cortex as the central node in these neural assemblies.

Evaluating the Image Quality of Neck Structures Scanned on Chest CT with Low-Concentration-Iodine Contrast Media.

BACKGROUND: The purpose of this study was to investigate and compare the image quality of low-concentration-iodine (240 mgI/mL) contrast media (CM) and high-concentration-iodine (320 mgI/mL) CM according to the radiation dose. METHODS: A total of 366 CT examinations were examined. Based on an assessment of quantitative and qualitative parameters by two radiologists, the quality was compared between Group A (low-concentration-iodine CM) and Group B (high-concentration-iodine CM) images of thyroid gland, sternocleidomastoid muscle (SCM), internal jugular vein (IJV), and common carotid artery (CCA). Another subgroup analysis compared Group a, (using ≤90 kVp in Group A), and Group b, (using ≥100 kVp in Group B) for finding the difference in image quality when the tube voltage is lowered. RESULTS: Image quality did not differ between Groups A and B or between Groups a and b. The signal-to-noise ratio and contrast-to-noise ratio were significantly higher for Group B than Group A for the thyroid gland, IJV, and CCA. No statistical differences were found in the comparison of all structures between Groups a and b. CONCLUSION: There was no significant difference in image quality based on CM concentration with variable radiation doses. Therefore, if an appropriate CT protocol is applied, clinically feasible neck CT images can be obtained even using low-concentration-iodine CM.

QTL Analysis and CAPS Marker Development Linked with Russet in Pear (Pyrus spp.).

The fruit skin types of pear (Pyrus spp.) are divided into russet, smooth, and intermediate. One of the important traits in pear breeding programs is russet on pear fruit skin because it affects the commercial value. In the present study, a high-density genetic linkage map of 'Whangkeumbae' (smooth) × 'Minibae' (russet) was constructed. In addition, quantitative trait loci (QTL) analysis was performed to identify russet related QTL and develop a cleaved amplified polymorphism sequence (CAPS) marker. Together with SNPs derived from Axiom Pear 70K Genotyping Array and genotyping-by-sequencing derived SNPs and SSRs generated in previous study, an integrated genetic linkage map of 'Whangkeumbae' × 'Minibae' was constructed. A total of 1263 markers were anchored in 17 linkage groups (LGs) with a total genetic distance of 1894.02 cM and an average marker density of 1.48 cM. The chromosome coverage of 'Whangkeumbae' × 'Minibae' map was improved because the SNPs derived from Axiom Pear 70K Genotyping Array were anchored. QTL analysis was performed using previous russet phenotype data evaluated with russet coverage and Hunter a. As a result of QTL analysis, russet coverage- and Hunter a-related QTLs were identified in LG8 of the 'Whangkeumbae' × 'Minibae' map, and SNPs located in the QTL region were heterozygous in the 'Minibae'. Although the russet coverage- and Hunter a-related QTLs were commonly detected in LG8, the logarithm of odds values of SNPs in the QTL region were higher in QTL related to russet coverage than to Hunter a. The CAPS marker (CBp08ca01) was developed using an array SNP located in the russet coverage related QTL, and the genotype of CBp08ca01 showed a 1:1 ratio in 'Whangkeumbae' × 'Minibae' (χ2 = 0.65, p > 0.05). 'Whangkeumbae' and 'Minibae' were thought to have rr and Rr genotypes, respectively, and the genetic factors controlling the russet formation might be located in chromosome 8. The CBp08ca01 was able to select F1 individuals with less than 30% russet coverage. Thus, it will be a useful tool for marker-assisted selection in pears.

Perturbation of Circadian Rhythm Is Associated with Increased Prevalence of Chronic Kidney Disease: Results of the Korean Nationwide Population-Based Survey.

Disturbances in circadian rhythms cause several health problems, such as psychosis, metabolic syndrome, and cancer; however, their effect on kidney disease remains unclear. This study aimed to evaluate the association between chronic kidney disease (CKD) and sleep disturbance in a Korean adult population. A total of 17,408 participants who completed the National Health and Nutrition Examination Survey from 2016 to 2018 were assessed for their sleep patterns and renal function. CKD was defined as an estimated glomerular filtration rate ≤ 60 mL/min/1.73 m² or a positive dipstick urinalysis. Sleep onset time and sleep duration showed significant differences between the control and CKD groups (p < 0.001). After adjusting for the covariates, sleep onset time rather than sleep duration was independently associated with incidence of CKD, and this association was more significant in people who were older, in women, and in those with low body mass index and no comorbidities. When comparing the prevalence of newly diagnosed CKD according to sleep onset time in a population with no CKD risk factors or no history of CKD, the early bedtime group showed an independent association with incidence of new CKD (odds ratio (OR), 1.535; 95% confidence interval (CI), 1.011−2.330) even after adjusting for covariates. Impaired circadian rhythm along with sleep disturbance could be associated with CKD development; therefore, sleep disturbance might be an important therapeutic target for CKD.

Chemical Upcycling of Commercial Polystyrene via Catalyst-Controlled Photooxidation.

Chemical upcycling of polystyrene into targeted small molecules is desirable to reduce plastic pollution. Herein, we report the upcycling of polystyrene to benzoyl products, primarily benzoic acid, using a catalyst-controlled photooxidative degradation method. FeCl3 undergoes a homolytic cleavage upon irradiation with white light to generate a chlorine radical, abstracting an electron-rich hydrogen atom on the polymer backbone. Under the oxygen-rich environment, high MW polystyrene (>90 kg/mol) degrades down to <1 kg/mol and produces up to 23 mol % benzoyl products. A series of mechanistic studies showed that chlorine radicals promoted the degradation via hydrogen-atom abstraction. Commercial polystyrene degrades efficiently in our method, showing the compatibility of our system with polymer fillers. Finally, we demonstrated the potential of scaling up our approach in a photoflow process to convert gram quantities of PS to benzoic acid.

Electrophysiological Responses to Rapidly-Presented Affective Stimuli Predict Individual Differences in Subsequent Attention.

We are constantly surrounded by a dynamically changing perceptual landscape that can influence our behavior even without our full conscious awareness. Emotional processing can have effects on subsequent attention, but there are mixed findings on whether it induces attentional enhancement or interference. The present study used a new multimodal approach to explain and predict such attentional effects based on individual differences in response to emotional stimuli. We briefly presented affective pictures (neutral, positive, erotic, mutilation, and horror categories) for 80 ms, immediately followed by a cued flanker task that was unrelated to the pictures. Event-related potentials (ERPs), skin conductance response (SCR), and reaction time (RT) were measured for each participant. We found that, in general, affective pictures induced higher electrophysiological responses compared with neutral pictures [P300 and late positive potential (LPP) in the erotic condition; P300, LPP, and SCR in the horror condition]. In particular, individuals who showed a strong ERP response to the pictures were impeded in the erotic condition (only P300) and facilitated in the horror condition (both P300 and LPP). Those who did not show a significant ERP or SCR response to the pictures were facilitated in the erotic condition and impeded in the horror condition. Furthermore, it was possible to classify the direction of the attentional effect from the participants' P300, LPP, and SCR responses. These results demonstrate that underlying individual differences in emotional processing must be considered in understanding and predicting the effects of emotions on attention and cognition.

A Novel Pear Scab (Venturia nashicola) Resistance Gene, Rvn3, from Interspecific Hybrid Pear (Pyrus pyrifolia × P. communis).

Asian pear scab is a fungal disease caused by Venturia nashicola. The identification of genes conferring scab resistance could facilitate the breeding of disease-resistant cultivars. Therefore, the present study aimed to identify a scab-resistance gene using an interspecific hybrid population ((Pyrus pyrifolia × P. communis) × P. pyrifolia). Artificial inoculation of V. nashicola was carried out for two years. The segregation ratio (1:1) of resistant to susceptible individuals indicated that resistance to V. nashicola was inherited from P. communis and controlled by a single dominant gene. Based on two years phenotypic data with the Kruskal-Wallis test and interval mapping, 12 common markers were significantly associated with scab resistance. A novel scab resistance gene, Rvn3, was mapped in linkage group 6 of the interspecific hybrid pear, and co-linearity between Rvn3 and one of the apple scab resistance genes, Rvi14, was confirmed. Notably, an insertion in pseudo-chromosome 6 of the interspecific hybrid cultivar showed homology with apple scab resistance genes. Hence, the newly discovered Rvn3 was considered an ortholog of the apple scab resistance gene. Since the mapping population used in the present study is a pseudo-BC1 population, pyramiding of multiple resistance genes to pseudo-BC1 could facilitate the breeding of pear cultivars with durable resistance.

Determinants for bedside lateralization of benign paroxysmal positional vertigo involving the horizontal semicircular canal.

OBJECTIVES: This study aimed to define the factors affecting accuracy of bedside determination of the involved side in HC-BPPV. INTERVENTIONS: We developed 44 video clips including the nystagmus induced during supine head-roll test from patients with apogeotropic (n = 23) or geotropic (n = 21) HC-BPPV. The intensity of nystagmus was also quantified using video-oculography. Each video clip was presented twice to 25 participants, 14 medical students, and 11 medical personnel trained in neurology or neurotology, and the participants reported the lesion side using an evaluation sheet after each presentation. From the quantified video-oculographic data, absolute difference and asymmetry (absolute difference divided by the sum) of nystagmus intensity were calculated. MAIN OUTCOMES AND MEASURES: The accuracy of bedside lateralization of HC-BPPV was 83.5% after the first presentation, and 86.0% after the second presentation, and was not different between the medical students and trained personnel after the second presentation. The accuracy was more closely correlated with the asymmetry than the absolute difference (Spearman's ρ = 0.627, p < 0.001). With a cut-off for the asymmetry at 30.8%, the accuracy was estimated at 93.8% with a sensitivity of 92.9%, and the area under the ROC curve of 0.779. CONCLUSIONS AND RELEVANCE: The accuracy of bedside lateralization of the affected side is acceptable in HC-BPPV when the nystagmus asymmetry is more than 30%.

Neurofeedback and neuroplasticity of visual self-processing in depressed and healthy adolescents: A preliminary study.

Adolescence is a neuroplastic period for self-processing and emotion regulation transformations, that if derailed, are linked to persistent depression. Neural mechanisms of adolescent self-processing and emotion regulation ought to be targeted via new treatments, given moderate effectiveness of current interventions. Thus, we implemented a novel neurofeedback protocol in adolescents to test the engagement of circuits sub-serving self-processing and emotion regulation. METHODS: Depressed (n = 34) and healthy (n = 19) adolescents underwent neurofeedback training using a novel task. They saw their happy face as a cue to recall positive memories and increased displayed amygdala and hippocampus activity. The control condition was counting-backwards while viewing another happy face. A self vs. other face recognition task was administered before and after neurofeedback training. RESULTS: Adolescents showed higher frontotemporal activity during neurofeedback and higher amygdala and hippocampus and hippocampi activity in time series and region of interest analyses respectively. Before neurofeedback there was higher saliency network engagement for self-face recognition, but that network engagement was lower after neurofeedback. Depressed youth exhibited higher fusiform, inferior parietal lobule and cuneus activity during neurofeedback, but controls appeared to increase amygdala and hippocampus activity faster compared to depressed adolescents. CONCLUSIONS: Neurofeedback recruited frontotemporal cortices that support social cognition and emotion regulation. Amygdala and hippocampus engagement via neurofeedback appears to change limbic-frontotemporal networks during self-face recognition. A placebo group or condition and contrasting amygdala and hippocampus, hippocampi or right amygdala versus frontal loci of neurofeedback, e.g. dorsal anterior cingulate cortex, with longer duration of neurofeedback training will elucidate dosage and loci of neurofeedback in adolescents.

The role of senescence of bone marrow cells in acute kidney injury.

BACKGROUND: The prevalence of acute kidney injury (AKI) in elderly patients has grown considerably. Age-associated changes in the immune system can be one of the critical factors determining AKI outcomes. This study aimed to investigate the role of senescence of bone marrow (BM)-derived cells in the development of AKI, focusing on the immune response. METHODS: Female 7-week-old C57BL/6 mice were irradiated and treated with BM cells from either 48-week-old or 8-week-old male mice. Ischemia-reperfusion injury (IRI) was induced, and their functional deterioration, histological tubular damage, and inflammatory responses were compared. For the in vitro study, lipopolysaccharide (LPS)-stimulated cytokine production by BM cells from old and young mice were examined. RESULTS: At 24 hours after IRI, there was no significant difference in the number of circulating immune cells between the mice transplanted with old or young BM cells. However, the mice with old BM cells showed less functional deterioration and histological tubular injury than those with young BM cells. Moreover, macrophage infiltration and renal cytokine interleukin (IL)-12 levels were lower in the mice with old BM cells at 24 hours post-IRI. Consistently, the in vitro study showed that LPS-induced production of cytokines interferon-γ, monocyte chemoattractant protein-1, and IL-10 was attenuated in cultured old BM cells, suggesting that age-related functional changes in these cells may lead to reduced inflammation in IRI. CONCLUSION: Immunosenescence could affect the susceptibility and response to renal IRI. Further studies specifically addressing age-related alterations can help in the development of treatment strategies for elderly patients with AKI.

The efficacy and safety of adding either vildagliptin or glimepiride to ongoing metformin therapy in patients with type 2 diabetes mellitus.

OBJECTIVE: To compare the effects of either vildagliptin or glimepiride on glycemic variability, oxidative stress, and endothelial parameters in patients with type 2 diabetes mellitus (T2DM) inadequately controlled with metformin alone. METHODS: In this randomized, open-label, parallel study, 34 patients with T2DM being treated with metformin having an HbA1c of 7.0-10.0% were allocated into either the vildagliptin or glimepiride group. A mixed-meal tolerance test and 72-hour continuous glucose monitoring were conducted, and urinary 8-iso-prostaglandinF2α (PGF2α) and endothelial-dependent flow-mediated dilatation (FMD) were evaluated at baseline and after 12 weeks of treatment. RESULTS: Similar significant improvements in HbA1c level were shown in both vildagliptin (-0.8%) and glimepiride (-0.9%) groups after treatment (Ps<0.001). The mean amplitude of glycemic excursions (MAGE) and the mean of daily differences (MODD) were significantly decreased by vildagliptin (P = 0.044 and P = 0.031, respectively) but not by glimepiride. Glimepiride was significantly associated with a higher incidence of hypoglycemia than vildagliptin (P = 0.005). There were no significant differences in urinary 8-iso-PGF2α or FMD between the two groups. CONCLUSIONS: Vildagliptin effectively improved glucose level with a significantly greater reduction in glycemic variability and hypoglycemia than glimepiride in patients with T2DM ongoing metformin therapy. The two drugs showed no significant differences in urinary 8-iso-PGF2α and FMD. TRIAL REGISTRATION: NCT01404676.

Prevalence of chronic disease and its controlled status according to income level.

The relationship between the prevalence of chronic diseases and income level has now become a main theme in poor national economic situations. We examined the prevalence of well-controlled chronic diseases according to income level. Data from the 2008 to 2014 Korea National Health and Nutrition Examination Survey, conducted by using a stratified, multistage, probability-cluster sampling method, were used. Systolic blood pressure (SBP) inversely correlated with income level (P < 0.001). Diastolic blood pressure (DBP) showed no relationship. In the low-income group, the prevalence rates of hypertension and diabetes mellitus (DM) were highest but the proportion of patients with well-controlled chronic disease and the SBPs of the patients with hypertension showed a decreasing trend. In the high-income group, the proportions of patients with well-controlled DM and chronic kidney disease were higher than those in other groups. After adjusting for age, body mass index, SBP, DBP, HbA1c level, and serum creatinine level, income level significantly affected the prevalence of chronic diseases (for income, ß=0.184; 95% confidence interval, 1.105-1.042). The daily sodium intake estimated by using spot urine samples was higher in the low- and low-to-mid-income groups. The prevalence of not using essential medical service for chronic disease was highest in the low- and low-to-mid-income groups for economic reasons. In the low- and low-to-mid-income groups, the prevalence of chronic disease was higher and the proportion of patients with well-controlled chronic disease was lower than in the other groups.

The association between glycemic variability and diabetic cardiovascular autonomic neuropathy in patients with type 2 diabetes.

BACKGROUND: It is presently unclear whether glycemic variability is associated with diabetic cardiovascular autonomic neuropathy (CAN). The aim of this study was to examine whether short- and/or long-term glycemic variability (GV) contribute to CAN. METHODS: A total of 110 patients with type 2 diabetes who underwent three-day continuous glucose monitoring (CGM) completed five standardized autonomic neuropathy tests. Short-term GV was measured by the standard deviation (SD), coefficient of variation (CV) of glucose, and the mean amplitude of glycemic excursions (MAGE) in CGM. HbA1c variability was calculated from the intrapersonal SD, adjusted SD, and CV of serial HbA1c over 2-year period. CAN was defined as the presence of at least two abnormal parasympathetic function tests. The severity of CAN was evaluated by total scores of five autonomic function tests. RESULTS: In univariate analysis, not only SD and CV in CGM but also all parameters of HbA1c variability were significantly higher in the patients with CAN (n = 47, 42.7 %) than in those without CAN. In multivariate analysis, CV (Odds ratio [OR] 1.07, 95 % confidence interval [CI] 1.01-1.13; p = 0.033), but neither SD nor MAGE in CGM, independently correlated with the presence of CAN. All parameters of HbA1c variability, such as SD of HbA1c (OR 12.10 [95 % CI 2.29-63.94], p = 0.003), adjusted SD of HbA1c (OR 17.02 [95 % CI 2.66-108.86], p = 0.003), and log CV of HbA1c (OR 24.00 [95 % CI 3.09-186.48], p = 0.002), were significantly associated with the presence of CAN. The patients with higher HbA1c variability had an increased risk of advanced CAN. CONCLUSION: CV in CGM and all parameters of HbA1c variability were independently associated with the presence of CAN in patients with inadequately controlled type 2 diabetes requiring CGM.

Hypoxia-inducible factor activation protects the kidney from gentamicin-induced acute injury.

Gentamicin nephrotoxicity is one of the most common causes of acute kidney injury (AKI). Hypoxia-inducible factor (HIF) is effective in protecting the kidney from ischemic and toxic injury. Increased expression of HIF-1α mRNA has been reported in rats with gentamicin-induced renal injury. We hypothesizd that we could study the role of HIF in gentamicin-induced AKI by modulating HIF activity. In this study, we investigated whether HIF activation had protective effects on gentamicin-induced renal tubule cell injury. Gentamicin-induced AKI was established in male Sprague-Dawley rats. Cobalt was continuously infused into the rats to activate HIF. HK-2 cells were pre-treated with cobalt or dimethyloxalylglycine (DMOG) to activate HIF and were then exposed to gentamicin. Cobalt or DMOG significantly increased HIF-1α expression in rat kidneys and HK-2 cells. In HK-2 cells, HIF inhibited gentamicin-induced reactive oxygen species (ROS) formation. HIF also protected these cells from apoptosis by reducing caspase-3 activity and the amount of cleaved caspase-3, and -9 proteins. Increased expression of HIF-1α reduced the number of gentamicin-induced apoptotic cells in rat kidneys and HK-2 cells. HIF activation improved the creatinine clearance and proteinuria in gentamicin-induced AKI. HIF activation also ameliorated the extent of histologic injury and reduced macrophage infiltration into the tubulointerstitium. In gentamicin-induced AKI, the activation of HIF by cobalt or DMOG attenuated renal dysfunction, proteinuria, and structural damage through a reduction of oxidative stress, inflammation, and apoptosis in renal tubular epithelial cells.

A Case of Acute Carbon Monoxide Poisoning Resulting in an ST Elevation Myocardial Infarction.

Carbon monoxide (CO) is a well-known chemical asphyxiant, which causes tissue hypoxia with prominent neurological and cardiovascular injury. After exposure to CO, several cardiac manifestations have been reported, including arrhythmias, acute myocardial infarction, and pulmonary edema. However, an ST elevation myocardial infarction (STEMI) due to CO poisoning is a very rare presentation, and the treatment for STEMI due to CO poisoning is not well established. Here, we report a rare case of STEMI complicated by increased thrombogenicity secondary to acute CO poisoning and complete revascularization after antithrombotic treatment.