Plasma Leptin and Alzheimer Protein Pathologies Among Older Adults.

Importance: Many epidemiologic studies have suggested that low levels of plasma leptin, a major adipokine, are associated with increased risk of Alzheimer disease (AD) dementia and cognitive decline. Nevertheless, the mechanistic pathway linking plasma leptin and AD-related cognitive decline is not yet fully understood. Objective: To examine the association of plasma leptin levels with in vivo AD pathologies, including amyloid-beta (Aß) and tau deposition, through both cross-sectional and longitudinal approaches among cognitively unimpaired older adults. Design, Setting, and Participants: This was a longitudinal cohort study from the Korean Brain Aging Study for Early Diagnosis and Prediction of Alzheimer Disease. Data were collected from January 1, 2014, to December 31, 2020, and data were analyzed from July 11 to September 6, 2022. The study included a total of 208 cognitively unimpaired participants who underwent baseline positron emission tomography (PET) scans for brain Aß deposition. For longitudinal analyses, 192 participants who completed both baseline and 2-year follow-up PET scans for brain Aß deposition were included. Exposure: Plasma leptin levels as assessed by enzyme-linked immunosorbent assay. Main Outcomes and Measures: Baseline levels and longitudinal changes of global Aß and AD-signature region tau deposition measured by PET scans. Results: Among the 208 participants, the mean (SD) age was 66.0 (11.3) years, 114 were women (54.8%), and 37 were apolipoprotein E ε4 carriers (17.8%). Lower plasma leptin levels had a significant cross-sectional association with greater brain Aß deposition (ß = -0.04; 95% CI, -0.09 to 0.00; P = .046), while there was no significant association between plasma leptin levels and tau deposition (ß = -0.02; 95% CI, -0.05 to 0.02; P = .41). In contrast, longitudinal analyses revealed that there was a significant association between lower baseline leptin levels and greater increase of tau deposition over 2 years (ß = -0.06; 95% CI, -0.11 to -0.01; P = .03), whereas plasma leptin levels did not have a significant association with longitudinal change of Aß deposition (ß = 0.006; 95% CI, 0.00-0.02; P = .27). Conclusions and Relevance: The present findings suggest that plasma leptin may be protective for the development or progression of AD pathology, including both Aß and tau deposition.

Structural alignment of ZnO columns across multiple monolayer MoS2 layers as compliant substrates.

Understanding the behavior of materials in multi-dimensional architectures composed of atomically thin two-dimensional (2D) materials and three-dimensional (3D) materials has become mandatory for progress in materials preparation via various epitaxy techniques, such as van der Waals and remote epitaxy methods. We investigated the growth behavior of ZnO on monolayer MoS2 as a model system to study the growth of a 3D material on a 2D material, which is beyond the scope of remote and van der Waals epitaxy. The study revealed column-to-column alignment and inversion of crystallinity, which can be explained by combinatorial epitaxy, grain alignment across an atomically sharp interface, and a compliant substrate. The growth study enabled the formation of a ZnO/MoS2 heterostructure with type-I band alignment. Our findings will have a scientific impact on realizing 2D/3D heterostructures for practical device applications.

Association between brain amyloid deposition and longitudinal changes of white matter hyperintensities.

BACKGROUND: Growing evidence suggests that not only cerebrovascular disease but also Alzheimer's disease (AD) pathological process itself cause cerebral white matter degeneration, resulting in white matter hyperintensities (WMHs). Some preclinical evidence also indicates that white matter degeneration may precede or affect the development of AD pathology. This study aimed to clarify the direction of influence between in vivo AD pathologies, particularly beta-amyloid (Aß) and tau deposition, and WMHs through longitudinal approach. METHODS: Total 282 older adults including cognitively normal and cognitively impaired individuals were recruited from the Korean Brain Aging Study for the Early Diagnosis and Prediction of Alzheimer's Disease (KBASE) cohort. The participants underwent comprehensive clinical and neuropsychological assessment, [11C] Pittsburgh Compound B PET for measuring Aß deposition, [18F] AV-1451 PET for measuring tau deposition, and MRI scans with fluid-attenuated inversion recovery image for measuring WMH volume. The relationships between Aß or tau deposition and WMH volume were examined using multiple linear regression analysis. In this analysis, baseline Aß or tau were used as independent variables, and change of WMH volume over 2 years was used as dependent variable to examine the effect of AD pathology on increase of WMH volume. Additionally, we set baseline WMH volume as independent variable and longitudinal change of Aß or tau deposition for 2 years as dependent variables to investigate whether WMH volume could precede AD pathologies. RESULTS: Baseline Aß deposition, but not tau deposition, had significant positive association with longitudinal change of WMH volume over 2 years. Baseline WMH volume was not related with any of longitudinal change of Aß or tau deposition for 2 years. We also found a significant interaction effect between baseline Aß deposition and sex on longitudinal change of WMH volume. Subsequent subgroup analyses showed that high baseline Aß deposition was associated with increase of WMH volume over 2 years in female, but not in male. CONCLUSIONS: Our findings suggest that Aß deposition accelerates cerebral WMHs, particularly in female, whereas white matter degeneration appears not influence on longitudinal Aß increase. The results also did not support any direction of influence between tau deposition and WMHs.

Neurodiagnostic and neurotherapeutic potential of graphene nanomaterials.

Graphene has emerged as a highly promising nanomaterial for a variety of advanced technologies, including batteries, energy, electronics, and biotechnologies. Its recent contribution to neurotechnology is particularly noteworthy because its superior conductivity, chemical resilience, biocompatibility, thermal stability, and scalable nature make it well-suited for measuring brain activity and plasticity in health and disease. Graphene-mediated compounds are microfabricated in two central methods: chemical processes with natural graphite and chemical vapor deposition of graphene in a film form. They are widely used as biosensors and bioelectronics for neurodiagnostic and neurotherapeutic purposes in several brain disorders, such as Parkinson's disease, stroke, glioma, epilepsy, tinnitus, and Alzheimer's disease. This review provides an overview of studies that have demonstrated the technical advances of graphene nanomaterials in neuroscientific and clinical applications. We also discuss current limitations and future demands in relation to the clinical application of graphene, highlighting its potential technological and clinical significance for treating brain disorders. Our review underscores the potential of graphene nanomaterials as powerful tools for advancing the understanding of the brain and developing new therapeutic strategies.

Severe pulmonary edema occurred during endobronchial ultrasound under monitored anesthesia care - A case report.

BACKGROUND: Endobronchial ultrasound (EBUS) is widely used to diagnose lung cancer. Monitored anesthesia care (MAC) can enhance patient comfort and procedural conditions during EBUS. EBUS under MAC is usually safe but can lead to various complications. CASE: A 34-year-old male who had increased sputum for two months showed an enlarged paratracheal lymph node and planned for lymph node biopsy by EBUS. During EBUS under MAC, an unexpected oxygen saturation decline required intervention. After intubation, copious frothy fluid was suctioned from the bronchi, and oxygenation was recovered. A narrowed trachea and the EBUS bronchoscope might have resulted in upper airway obstruction, and suction performed under these conditions might have caused pulmonary edema. The patient received non-invasive ventilation and high-flow nasal cannula and recovered without complications. CONCLUSIONS: When there is an expected risk of upper airway obstruction during EBUS, careful preoperative evaluation and preparation are essential to prevent negative pressure pulmonary edema.

Development of a Cognitive Composite for Preclinical Alzheimer's Disease in Korean Older Adults.

BACKGROUND: As tracking subtle cognitive declines in the preclinical stage of Alzheimer's disease (AD) is difficult with traditional individual outcome measures, need for cognitive composite for preclinical AD is widely recognized. OBJECTIVE: We aimed to develop culturally appropriate cognitive composite that sensitively identifies subtle cognitive decline of preclinical AD in Korean older adults. METHODS: A total 225 cognitively normal elderly individuals from the Korean Brain Aging Study for the Early Diagnosis and Prediction of Alzheimer's Disease, were included. Tests of episodic memory, orientation, and executive function were carefully selected through review of previously established composites. Three candidate composites including Consortium to Establish a Registry for Alzheimer's Disease Word list recall (WLR), Logical memory (LM) II, and Mini-Mental status examination (MMSE) in common, and Letter fluency test (LF), category fluency test, or Stroop color and word test, were selected. RESULTS: Student t-tests demonstrated that only the composite composed of WLR, LM II, MMSE, and LF (Composite 1) showed a significant difference in score decline over two-year follow-up period between Aß positive and negative group (p = 0.03). Linear mixed model analyses also showed that the Aß x time interaction effect was significant only for Composite 1 (p = 0.025). Based on the results, Composite 1 was chosen as the final cognitive composite for preclinical Alzheimer's disease (CPAD). CONCLUSIONS: CPAD can be used to assess subtle cognitive decline of preclinical AD in clinical research settings, especially in Korean older adults. It also may be used for monitoring progression or treatment benefits in clinical practices.

Phenolic compounds in the freshwater environment in South Korea: Occurrence and tissue-specific distribution.

In this study, we investigated the occurrence and distribution of phenolic compounds, including phenol, cresols, chlorophenols, nitrophenol, and bromophenols, in freshwater environments. We also focused on phenolic compounds in crucian carp (Carassius auratus) tissues, specifically the muscle, gills, brain, blood, liver, and gonads, to assess their potential bioaccumulation in fish and human health risks. Phenolic compounds were found to be widespread in various freshwater environments throughout South Korea. Phenol was predominant in all matrices, with median concentrations of 57.0 ng/L in freshwater, 54.3 ng/g dry weight (dw) in sediment, and ranging from 71 ng/g wet weight (ww) to 621 ng/g ww in crucian carp tissues. Cresols were the second most dominant compound, with m-cresol exhibiting the highest prevalence. Most of the compounds detected in crucian carp samples were also detected in freshwater and sediment, whereas pentachlorophenol and 2,4,6-tribromophenol were exclusively detected in crucian carp tissues. A high bioaccumulation potential in the liver was observed for most phenolic compounds [median log bioconcentration factor (BCF): 3.2-3.7]. Interestingly, only m-cresol showed high bioaccumulation potential in the gills (median log BCF: 3.1). The estimated daily intake of phenolic compounds suggested that it does not pose an immediate concern for human exposure owing to crucian carp consumption. These findings enhance our understanding of the exposure status, distribution, and bioaccumulation potency of phenolic compounds in aquatic ecosystems and emphasize the importance of ongoing monitoring and risk assessment efforts.

Anesthetic management of an elderly COVID-19 patient with pulmonary thromboembolism for hip surgery - A case report.

BACKGROUND: COVID-19 and delayed hip surgery are well-known risk factors for thromboembolism in elderly patients. CASE: We report the case of an 88-year-old female patient with COVID-19 and pulmonary thromboembolism (PTE) who underwent delayed hip surgery 21 days after the injury. Heparinization and inferior vena cava filters were used to treat and prevent PTE. Transesophageal echocardiography and extracorporeal membrane oxygenation (ECMO) sheaths were inserted as a precaution in case of emergencies during surgery; the procedure was performed without any specific event. CONCLUSIONS: COVID-19-infected patients suffering from a hip fracture have a high risk of thromboembolism, and therefore, require utmost attention for appropriate evaluation and prevention.

Reconstruction of Range-Doppler Map Corrupted by FMCW Radar Asynchronization.

Frequency-modulated continuous wave (FMCW) radar system synchronization using external clock signals can cause repeated Range-Doppler (R-D) map corruption when clock signal asynchronization problems occur between the transmitter and receiver. In this paper, we propose a signal processing method for the reconstruction of the corrupted R-D map owing to the FMCW radar's asynchronization. After calculating the image entropy for each R-D map, the corrupted ones are extracted and reconstructed using the normal R-D maps acquired before and after the individual maps. To verify the effectiveness of the proposed method, three target detection experiments were conducted: a human target detection in an indoor environment and a wide place and a moving bike-rider target detection in an outdoor environment. The corrupted R-D map sequence of observed targets in each case was reconstructed properly and showed the validity by comparing the map-by-map range and speed changes in the detected target with the ground-truth information of the target.

Effect of cresol isomers on reproduction and gene expression in Daphnia magna.

Cresols are frequently detected in freshwater systems due to their wide use as disinfectants. However, there is limited knowledge regarding their adverse long-term toxicity effects on reproduction and gene expression patterns of aquatic species. Therefore, this study aimed to investigate the chronic toxic effects on reproduction and gene expression using D. magna. In addition, the bioconcentration behaviour of cresol isomers was also investigated. Based on the 48 h EC50 value, p-cresol's toxicity unit (TU) (13.77 TU, very toxic) was higher than o-cresol (8.05 TU, toxic) and m-cresol (5.52 TU, toxic). Regarding population-level effects, cresols resulted in a decrease in offspring and a delay in reproduction. However, cresols did not significantly affect daphnia's body weight throughout the course of the exposure period of 21 day, while third brood neonates' average body length (m-cresol and p-cresol) was significantly affected in sub-lethal concentrations. In addition, the gene transcription did not vary significantly across treatments. For bioconcentration exposure experiments, D. magna quickly eliminated all cresols from their body, suggesting that cresol isomers are unlikely to bioaccumulate in aquatic species.

Evaluation of Lattice Light Shift at Low 10

A Wannier-Stark optical lattice clock has demonstrated unprecedented measurement precision for optical atomic clocks. We present a systematic evaluation of the lattice light shift, a necessary next step for establishing this system as an accurate atomic clock. With precise control of the atomic motional states in the lattice, we report accurate measurements of the multipolar and the hyperpolar contributions and the operational lattice light shift with a fractional frequency uncertainty of 3.5×10^{-19}.

Catatonia associated with prolonged stupor after general anesthesia in a patient with multiple neuropsychiatric disorders -a case report.

BACKGROUND: Delayed emergence after general anesthesia may significantly affect a patient's condition. We present the case of a patient who experienced prolonged delayed recovery of consciousness, language, and motor response due to catatonia after eight hours of total elbow arthroplasty under general anesthesia. CASE: A 68-year-old woman with neuropsychiatric disorders and Parkinson's disease did not respond adequately during recovery after more than eight hours of general anesthesia. Following the operation, the patient was semi-comatose and appeared to have nonconvulsive status epilepticus upon awakening from anesthesia. However, subsequent examinations did not reveal any organic causes. The patient was subsequently diagnosed with catatonia, treated, and discharged following gradual improvement. CONCLUSIONS: Although rare, patients taking psychiatric drugs for an extended period may experience delayed emergence after prolonged general anesthesia without identifiable causes. Catatonia should be considered in the differential diagnoses of these patients.

Noninvasive Ventilation for Acute Respiratory Failure in Pediatric Patients: A Systematic Review and Meta-Analysis.

OBJECTIVE: To perform a systematic review and meta-analysis of randomized controlled trials (RCTs) on the use of noninvasive ventilation (NIV) for acute respiratory failure (ARF) in pediatric patients. DATA SOURCES: We searched PubMed, EMBASE, the Cochrane Central Register of Clinical Trials, and Clinicaltrials.gov with a last update on July 31, 2022. STUDY SELECTION: We included RCTs comparing NIV with any comparator (standard oxygen therapy and high-flow nasal cannula [HFNC]) in pediatric patients with ARF. We excluded studies performed on neonates and on chronic respiratory failure patients. DATA EXTRACTION: Baseline characteristics, intubation rate, mortality, and hospital and ICU length of stays were extracted by trained investigators. DATA SYNTHESIS: We identified 15 RCTs (2,679 patients) for the final analyses. The intubation rate was 109 of 945 (11.5%) in the NIV group, and 158 of 1,086 (14.5%) in the control group (risk ratio, 0.791; 95% CI, 0.629-0.996; p = 0.046; I2 = 0%; number needed to treat = 31). Findings were strengthened after removing studies with intervention duration shorter than an hour and after excluding studies with cross-over as rescue treatment. There was no difference in mortality, and ICU and hospital length of stays. CONCLUSIONS: In pediatric patients, NIV applied for ARF might reduce the intubation rate compared with standard oxygen therapy or HFNC. No difference in mortality was observed.

Clozapine Blood Concentration Predicts Corrected QT-Interval Prolongation in Patients With Psychoses.

BACKGROUND: Corrected QT-interval (QTc) prolongation (QTP) is a rare but fatal adverse effect of antipsychotics. Clozapine is the only antipsychotic recommended for treatment of resistant schizophrenia; however, clozapine has been reported to cause QTP. We sought factors predictive of QTP in patients who had antipsychotic polypharmacy involving clozapine. We explored whether the clozapine blood concentration might predict QTP. METHODS: We included 133 patients with schizophrenia spectrum disorder who had antipsychotic polypharmacy involving clozapine. We used the χ2 and nonparametric tests to compare clozapine therapeutic drug monitoring (TDM) values and QTc-prolonged person (QTPP) status. Multivariate regression and mediator models were used to identify risk factors for QTPP status and QTP. RESULTS: In total, 111 patients were prescribed clozapine. The QTPP rates were 31.3% (20) for men and 23.2% (16) for women. Compared with the non-QTPP group, the QTPP group exhibited significantly higher daily dose of all antipsychotics including clozapine, a higher clozapine dose, and elevated clozapine and norclozapine TDM values. Furthermore, such patients were prescribed a greater number of antipsychotics. Multivariate logistic regression revealed that only the clozapine TDM value could be predictive factor for QTPP status (P = 0.018). A clozapine TDM value above the therapeutic range (>600 mg/dL) was associated with a high risk of QTPP status (adjusted odds ratio, 6.5; 95% confidence interval, 1.7-25.2; P = 0.006). The mediator model revealed that the clozapine TDM values completely mediated the association between the clozapine dose and the QTc interval. CONCLUSIONS: The clozapine blood concentration reliably predicts QTP in patients with clozapine use.

Evaluation of sample preparation methods for suspect and non-target screening in water, sediment, and biota samples using gas chromatography coupled to high-resolution mass spectrometry.

In this study, the sample preparation methods were proposed for the suspect and non-target screening (SNTS) using gas chromatography coupled to high-resolution mass spectrometry in the aquatic environment. The pretreatment methods were evaluated based on detection rates, recoveries, and screening detection limits (SDLs) for 316 substances spiked into surface water, sediment, and biota samples. The detection rates of the spiked compounds were 92.1 % and 98.7 % by the sample preparation methods for water (solid-phase extraction using HLB cartridge) and sediment (ultrasonic extraction (USE) with HLB cartridge clean-up), respectively. Similarly, USE with HLB cartridge clean-up gave the highest detection rate (87.9 %) for biota samples; however, additional pretreatment method using deactivated silica gel clean-up was necessary for the detection of persistent organic pollutants (POPs). The SDL ranges of spiked compounds by the suggested pretreatment methods were 0.01-23.5 ng/L for surface water, 0.02-37.5 ng/g dry weight for sediment, and 0.01-12.2 ng/g wet weight for biota. Although some pollutants, such as POPs had SDLs that were higher than the levels normally detected in the aquatic environment as reported in previous studies, the analytical methods suggested in the present study were satisfactory for the SNTS of most pollutants originated from anthropogenic sources.

Improved Polypropylene Thermoformability through Polyethylene Layering.

Due to its low cost, stiffness, and recyclability, isotactic polypropylene (iPP) is an excellent candidate for packaging applications. However, iPP is notoriously difficult to thermoform due to its low melt strength. The addition of just 10 thin layers of high-molecular-weight, linear low-density polyethylene (LLDPE) into iPP sheets by coextrusion significantly increased extensional viscosity and reduced sag. Both LLDPE and iPP were metallocene-catalyzed with excellent adhesion as measured in our previous work. We performed a series of hot tensile tests and sheet sag measurements to determine the properties of the iPP sheet and the multilayer sheet between 130 and 180 °C. To evaluate the thermoformability of these multilayer sheets, truncated conical cups were positive vacuum formed at different temperatures and heating times, and the crush strength was measured. Cups that released easily from the mold with good shape retention and a crush strength within 80% of the maximum value were used to define a temperature-time thermoformability window. We estimated the maximum stress that occurred during the thermoforming process to be 5 MPa. Layer thicknesses before and after thermoforming were used to estimate an average strain of 0.78. The thin LLDPE layers decreased the yield stress below 5 MPa. This enabled thermoforming at sheet temperatures as low as 150 °C. The immiscible LLDPE interfaces increased extensional viscosity, which decreased sag in the multilayer sheets compared to iPP. This broadened the thermoforming range to temperatures as high as 180 °C and allowed longer heating times. These highly thermoformable, layered sheets may be recycled as iPP since they contain only 8% of LLDPE.

Prophylactic use of donut-shaped cushion to reduce sacral pressure injuries during open heart surgery.

Background: Pressure injuries are likely to develop in the operating room due to the high temperature and humidity underneath the patients. This study was designed to reduce sacral pressure injuries using donut-shaped cushions on patients undergoing open heart surgery in a supine position for more than three hours. Materials and Methods: Patients undergoing open heart surgery for more than three hours were randomly allocated. Depending on the allocation, either the donut-shaped cushion (donut group) or hydrophilic foam dressing (control group) was applied before draping. Patients were evaluated for the development of pressure injuries, National Pressure Ulcer Advisory Panel (NPUAP) stage, and injury size immediately after surgery, 48 hours, and seven days after surgery. Results: Forty-five patients were enrolled in this study. Twenty-two were assigned to the donut group and 23 were assigned to the control group. Three patients developed pressure injuries of NPUAP stage I or higher. All injuries occurred in the control group, but there was no statistically significant difference (P = 0.083). Conclusions: Patients who underwent cardiac surgery for more than three hours and used a donut-shaped cushion did not develop pressure injuries, although no statistical difference was noted. Specific preventative measures in the operating room may play a crucial role in preventing pressure injuries, and further research should be pursued.

Two cases of late-onset cardiovascular toxicities after a single injection of local anesthetics during supraclavicular brachial plexus block - A report of two cases.

BACKGROUND: Local anesthetics systemic toxicity (LAST) is a grave complication of regional anesthesia that usually occurs immediately after local anesthetics injection. Here, we report on rare late-onset toxicity cases after supraclavicular brachial plexus blocks. CASE: Two patients underwent surgery for radius fractures. We used lidocaine 100 mg and ropivacaine 150 mg for blocking and infused dexmedetomidine for intraoperative sedation. The 63-year-old male patient's blood pressure dropped to 87/60 mmHg after 3 h 15 min after blocking. Ventricular fibrillation occurred 10 min later. After five defibrillations, electrocardiography showed ventricular tachycardia that was normalized through one cardioversion. The 54-year-old female patient's heart rate decreased to 35 beats/min 2 h 30 min after blocking. Her vital signs returned to normal after administering atropine, ephedrine, epinephrine, and lipid emulsion. CONCLUSIONS: Physicians should remember that LAST may occur long after local anesthetic injection and be aware of factors that may adversely affect the course of LAST.

1,2,3-benzotriazole adversely affects early-life stage of Oryzias latipes.

1,2,3-benzotriazole (BT) is used in large amounts around the world and is one of the substances derived from household chemicals that are of concern for risk when discharged to aquatic environments. Therefore, several studies have been conducted on the aquatic toxicity effects of BT, but the chronic impact assessment studies to evaluate the developmental effects on the early-life stage of fish are insufficient. In this study, the acute toxicity test and subchronic toxicity test (fish, early-life stage toxicity test, ELS test) using embryos of Japanese medaka (Oryzias latipes) were performed to evaluate the acute toxicity, developmental toxicity, growth (indicated by total length and weight at the end of the test), and histopathological effect of BT. In the short-term toxicity test on embryo and sac-fry stage, toxicity value was calculated to be 41 mg/L (NOEC). Based on this value, the exposure concentration of the ELS test was determined as 0.04, 0.4, 4 and 40 mg/L, and total exposure duration was 42 days. At the highest concentration group (40 mg/L), failure of swim bladder inflation and decrease of survival and size (total length and weight) were observed. Moreover, in the histopathological analysis, abnormal findings were detected in swim bladders from the 40 mg/L group such as inflammation and tumor changes. On the other hands, condition index (weight-length relationships, CI) was statistically significantly lower in all exposed groups compared to the control group. NOEC for the survival of BT was calculated to be 4 mg/L. LOEC for CI was 0.04 mg/L, which means BT inhibited weight gain relative to its length on larvae of medaka.

Effect of benzotriazole on oxidative stress response and transcriptional gene expression in Oryzias latipes and Danio rerio embryo.

Emerging contaminants (EC) such as benzotriazole are being released into the environment in various ways, therefore it is necessary to understand how organisms are affected by EC. In this study, we exposed medaka (Oryzias latipes) and zebrafish (Danio rerio) during their embryonic period (1 day after hatching) to benzotriazole to investigate its effects on oxidative stress (ROS, GSH, GST, SOD, CAT and MDA) and changes in gene expression patterns. In both medaka and zebrafish, the influence of oxidative stress was confirmed through an increased MDA level and changes in the ROS and GSH levels. Antioxidant enzymes such as GST, CAT, and SOD were affected by benzotriazole; however, medaka and zebrafish showed different patterns in the effects by benzotriazole. Results of oxidative stress genes expression showed that medaka had either no influence or had a decrease in the gene expression profile, whereas zebrafish had a statistically significant increase in the expression of some genes. The cyp1a gene expression was increased in both species. However, vtg gene expression was increased only in zebrafish but decreased in medaka, indicating no estrogenic effects in medaka. Apoptosis genes showed changes in expression in both the species but was these changes were not dose-dependent. However, zebrafish caspase-9 gene expression was increased in all of the exposed groups, suggesting the effects on the intrinsic pathway associated with caspase-9. In conclusion, the results indicate that the toxic effects of benzotriazole differ at various levels in the two small fish medaka and zebrafish embryos.