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1.
Artículo en Inglés | MEDLINE | ID: mdl-38965927

RESUMEN

Objectives: Estimating the number of deaths caused by smoking is crucial for developing and evaluating tobacco control and smoking cessation policies. This study aimed to determine smoking-attributable mortality (SAM) in Korea in 2020. Methods: Four large-scale cohorts from Korea were analyzed. A Cox proportional-hazards model was used to determine the hazard ratios (HRs) of smoking-related death. By conducting a meta-analysis of these HRs, the pooled HRs of smoking-related death for 41 diseases were estimated. Population-attributable fractions (PAFs) were calculated based on the smoking prevalence for 1995 in conjunction with the pooled HRs. Subsequently, SAM was derived using the PAF and the number of deaths recorded for each disease in 2020. Results: The pooled HR for all-cause mortality attributable to smoking was 1.73 for current male smokers (95% CI, 1.532-1.954) and 1.631 for current female smokers (95% CI, 1.371-1.94). Smoking accounted for 33.2% of all-cause deaths in men and 4.6% in women. Additionally, it was a factor in 71.8% of male lung cancer deaths and 11.9% of female lung cancer deaths. In 2020, smoking was responsible for 53,930 male deaths and 6,283 female deaths, totaling 60,213 deaths. Conclusions: Cigarette smoking was responsible for a significant number of deaths in Korea in 2020. Monitoring the impact and societal burden of smoking is essential for effective tobacco control and harm prevention policies.

2.
Insects ; 15(6)2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38921093

RESUMEN

High-risk termites in wood imported to the Republic of Korea are currently treated with methyl bromide (MB), which has ozone-depleting properties and is highly toxic. This study evaluated the effectiveness of sulfuryl fluoride (SF) as a quarantine treatment against Reticulitermes speratus Kolbe (Blattodea: Rhinotermitidae) in wood, along with its wood sorption and penetration capacity. The LCt50 and LCt99 values for SF were 30.87 and 42.53 mg h/L at 23 °C and 151.62 and 401.9 mg h/L at 5 °C, respectively. The SF Ct values did not significantly differ between dry and wet wood at loading ratios of 10%, 30%, and 50% at both 5 °C and 23 °C (p > 0.05). In a closed wooden cube, the LCt50 and LCt99 for SF for R. speratus were 31.59 and 53.34 mg h/L, respectively, indicating an excellent wood penetration ability. SF caused 100% termite mortality with a 90% loading ratio in the scale-up trials (500 L). The SF concentration during ventilation decreased below the threshold limit value (TLV) of 5 ppm within 30 min, confirming that the working conditions were safe. This study provides a basis for the use of SF as an alternative to MB for the treatment of termites in wood.

3.
Odontology ; 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38904919

RESUMEN

The enamel surface may undergo demineralization due to exposure to acidic substances and the remineralization of the etched enamel is crucial to regain or maintain integrity. This study aimed to investigate the erosive effect of 10 acidic solutions on tooth enamel and the remineralization capacity of milk and artificial saliva by measuring surface roughness (Ra), enamel depth, and microhardness. A total of 80 bovine incisor enamel specimens were immersed in 10 different acidic solutions, including four different acidic drinks, three different citric acid solutions, and three different citric acid buffer solutions, for 1 h. After demineralization, the specimens were immersed in milk and artificial saliva for 3 h. Surface roughness, enamel abraded depth, and microhardness were measured before demineralization, in-between time intervals and after remineralization. Data were analyzed using Friedman and Kruskal-Wallis tests (p < 0.05). The results indicate a significant difference in surface roughness between the measurements taken at different time intervals, particularly between the baseline and after 1 h demineralization. Also, the specimens immersed in CAB1 exhibited greatest increase in Ra among other acidic solutions (Δ: 0.18 ± 0.07). Moreover, only the microhardness increased after remineralization (p < 0.05). Enamel demineralization using various acidic solutions revealed increased Ra and enamel abraded depth, and decreased microhardness. The use of remineralization agents, milk and artificial saliva, demonstrated an increase in microhardness. This study provides insights into the effects of different acidic solutions and potential remineralization agents on tooth enamel.

4.
Pharmaceuticals (Basel) ; 17(6)2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38931394

RESUMEN

Yeokwisan (YWS) is an herbal medicine prescription consisting of six oriental herbal medicines, developed to treat reflux esophagitis. We focused on developing an analytical method capable of simultaneously quantifying 13 compounds in YWS samples using high-performance liquid chromatography-photodiode array detection (HPLC-PDA) and ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) and exploring their antioxidant effects. All compounds examined in both analytical systems were chromatographically separated on a SunFireTM C18 (4.6 × 250 mm, 5 µm) column and an Acquity UPLC BEH C18 (2.1 × 100 mm, 1.7 µm) column using gradient elution of a water-acetonitrile mobile phase. Antioxidant effects were evaluated based on radical scavenging activity (DPPH and ABTS tests) and ferrous ion chelating activity. In two analytical methods, the coefficient of determination of the regression equation was ≥0.9965, the recovery range was 81.11-108.21% (relative standard deviation (RSD) ≤ 9.33%), and the precision was RSD ≤ 11.10%. Application of the optimized analysis conditions gave quantitative analysis results for YWS samples of 0.02-100.36 mg/g. Evaluation of the antioxidant effects revealed that baicalein and baicalin exhibit significant antioxidant activity, suggesting that they play an important role in the antioxidant effects of YWS.

5.
Hum Vaccin Immunother ; 20(1): 2346966, 2024 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-38741240

RESUMEN

This research examines the low rate of co-administration of influenza and COVID-19 vaccines among seniors aged 65 and older in Korea, despite recommendations from authorities and academia worldwide. The study aimed to understand the influence of general characteristics and health beliefs on the vaccination choices of seniors, who were categorized into four groups based on their vaccination status: influenza only, COVID-19 only, both, or neither. A total of 400 participants, aged 65 and above, were selected through proportional stratified random sampling from five major Korean regions for a survey conducted between November 24th and December 15th, 2023. The results indicated no significant differences in general characteristics across these groups. However, regarding the health beliefs showed significant differences in perceived susceptibility and self-efficacy between the influenza-only and co-administration groups. Higher levels of perceived susceptibility and self-efficacy were associated with choosing co-administration. Contrary to previous studies focusing on safety concerns as a primary factor in vaccine hesitancy, this study highlights the role of individual health-related beliefs, particularly perceived susceptibility and self-efficacy, as critical in influencing the decision for co-administration among the elderly in Korea.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Vacunas contra la Influenza , Gripe Humana , Humanos , Anciano , Vacunas contra la Influenza/administración & dosificación , Masculino , Femenino , Gripe Humana/prevención & control , República de Corea , Vacunas contra la COVID-19/administración & dosificación , COVID-19/prevención & control , Anciano de 80 o más Años , Vacunación/psicología , Vacunación/estadística & datos numéricos , Vacilación a la Vacunación/estadística & datos numéricos , Vacilación a la Vacunación/psicología , Conocimientos, Actitudes y Práctica en Salud , Encuestas y Cuestionarios , Autoeficacia , SARS-CoV-2/inmunología , Toma de Decisiones
6.
Sci Immunol ; 9(95): eadq0015, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38701192

RESUMEN

Initial imprinting by type 1 interferons shapes memory B cell generation in chronic viral infection.


Asunto(s)
Linfocitos B , Humanos , Animales , Linfocitos B/inmunología , Interferón Tipo I/inmunología , Células B de Memoria/inmunología , Virosis/inmunología
7.
Br J Nutr ; : 1-26, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38804177

RESUMEN

The Dietary Approaches to Stop Hypertension (DASH) diet is highly effective in controlling blood pressure (BP). Although sodium restriction is not a primary focus within the DASH diet, it is recommended that it be added to control BP. Therefore, we aimed to systematically review the characteristics and BP-lowering effects of sodium-restricted DASH diet interventions. We searched 13 databases, namely, MEDLINE, Embase, Cochrane Central Register of Controlled Trials, KoreaMed, KISS, KMbase, RISS, CINAHL, Scopus, ClinicalTrials.gov, Grey Literature Report, OpenGrey, and PQDT Global, for articles published through May 2023. Randomised controlled trials assessing the BP-lowering effect of the sodium-restricted DASH diet in adults aged 18 years and older were included. The study protocol was registered in the PROSPERO registry (CRD42023409996). The risk of bias in the included studies was also assessed. Nine articles were included in this review. Interventions were categorised into three types: feeding, provision, and education, and the study results were compared by intervention type. BP was significantly reduced in two of the three feeding studies, one of the three provisional studies, and none of the educational studies. In eight studies, effect sizes varied among both systolic BP (-7.7 to -2.4) and diastolic BP (-8.3 to 0.1). Six studies showed an overall high risk of bias. In conclusion, sodium-restricted DASH may have beneficial effects on BP control. Additionally, compared to control interventions, feeding interventions appeared to have a greater BP-lowering effect. Further high-quality studies are needed to improve the quality of the evidence.

8.
Int Dent J ; 2024 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-38614882

RESUMEN

AIM: This study aimed to identify the optimal toothpaste for removing coffee-induced stains while also evaluating its impact on tooth enamel through roughness and abraded depth parameters, providing a comprehensive understanding of their effects. MATERIALS AND METHODS: Three whitening toothpastes and 2 conventional toothpastes were prepared for a simulated brushing procedure on coffee-stained bovine enamel tooth specimens. Using a toothbrushing machine, up to 10,000 brushstrokes were completed, while spectrophotometric readings were taken at designated intervals. A mixed-effects model for statistical analysis determined the effects of toothpaste and brushing on colour change, roughness, and abraded depth. RESULTS: Whitening toothpastes significantly deviated from the control (P < .001, P < .001, and P < .003, respectively), whereas the conventional toothpaste did not exhibit a significant contrast (P < .081). Regarding colour restoration following coffee staining, whitening toothpastes showed higher restoration than conventional toothpastes. Surface roughness and abraded depth parameters increased with accumulated brushing. CONCLUSIONS: Sodium hexametaphosphate-containing toothpaste demonstrated the highest efficacy in removing coffee-induced stains and restoring tooth colour. Nevertheless, this stronger whitening effect was associated with increased abrasion. While conventional toothpastes exhibited some whitening effects, the most substantial improvement in lightness was consistently observed with whitening toothpastes. CLINICAL RELEVANCE: Understanding how whitening toothpaste affects enamel integrity is crucial for refining formulations and advancing dental care. This knowledge lays the groundwork for more effective oral care products and improved whitening procedures, ultimately enhancing the overall quality of dental treatments.

9.
Nano Lett ; 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38619226

RESUMEN

Halide perovskite-based resistive switching memory (memristor) has potential in an artificial synapse. However, an abrupt switch behavior observed for a formamidinium lead triiodide (FAPbI3)-based memristor is undesirable for an artificial synapse. Here, we report on the δ-FAPbI3/atomic-layer-deposited (ALD)-SnO2 bilayer memristor for gradual analogue resistive switching. In comparison to a single-layer δ-FAPbI3 memristor, the heterojunction δ-FAPbI3/ALD-SnO2 bilayer effectively reduces the current level in the high-resistance state. The analog resistive switching characteristics of δ-FAPbI3/ALD-SnO2 demonstrate exceptional linearity and potentiation/depression performance, resembling an artificial synapse for neuromorphic computing. The nonlinearity of long-term potentiation and long-term depression is notably decreased from 12.26 to 0.60 and from -8.79 to -3.47, respectively. Moreover, the δ-FAPbI3/ALD-SnO2 bilayer achieves a recognition rate of ≤94.04% based on the modified National Institute of Standards and Technology database (MNIST), establishing its potential in an efficient artificial synapse.

10.
Nanoscale ; 16(19): 9462-9475, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38639449

RESUMEN

The dimerization of boron dipyrromethene (BODIPY) moieties is an appealing molecular design approach for developing heavy-atom-free triplet photosensitizers (PSs). However, BODIPY dimer-based PSs generally lack target specificity, which limits their clinical use for photodynamic therapy. This study reports the synthesis of two mitochondria-targeting triphenylphosphonium (TPP)-functionalized meso-ß directly linked BODIPY dimers (BTPP and BeTPP). Both BODIPY dimers exhibited solvent-polarity-dependent singlet oxygen (1O2) quantum yields, with maximum values of 0.84 and 0.55 for BTPP and BeTPP, respectively, in tetrahydrofuran. The compact orthogonal geometry of the BODIPY dimers facilitated the generation of triplet excited states via photoinduced charge separation (CS) and subsequent spin-orbit charge-transfer intersystem crossing (SOCT-ISC) processes and their rates were dependent on the energetic configuration between the frontier molecular orbitals of the two BODIPY subunits. The as-synthesized compounds were amphiphilic and hence formed stable nanoparticles (∼36 nm in diameter) in aqueous solutions, with a zeta potential of ∼33 mV beneficial for mitochondrial targeting. In vitro experiments with MCF-7 and HeLa cancer cells indicated the effective localization of BTPP and BeTPP within cancer-cell mitochondria. Under light irradiation, BTPP and BeTPP exhibited robust photo-induced therapeutic effects in both cell lines, with half-maximal inhibitory concentration (IC50) values of ∼30 and ∼55 nM, respectively.


Asunto(s)
Compuestos de Boro , Mitocondrias , Nanopartículas , Compuestos Organofosforados , Fotoquimioterapia , Fármacos Fotosensibilizantes , Oxígeno Singlete , Humanos , Compuestos de Boro/química , Compuestos de Boro/farmacología , Compuestos Organofosforados/química , Compuestos Organofosforados/farmacología , Mitocondrias/metabolismo , Mitocondrias/efectos de los fármacos , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacología , Nanopartículas/química , Oxígeno Singlete/metabolismo , Oxígeno Singlete/química , Células MCF-7 , Supervivencia Celular/efectos de los fármacos , Células HeLa , Dimerización
11.
Front Psychiatry ; 15: 1248963, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38654727

RESUMEN

Background: The influence of mindfulness-based intervention (MBI) programs on behavioural problems among community youth is largely understudied. While technology continues to evolve and the prevalence of screen-based activities is rising, limited studies have accounted for screen time when examining the efficacy of an MBI. Accordingly, this study investigated the impact of MBI on conduct problems and hyperactivity among community youth, accounting for sociodemographic characteristics and four types of screen time. Method: Linear regression models were used to investigate 1) the association between four types of screen time and behavioural problems (i.e., conduct problems and hyperactivity) and 2) the efficacy of online mindfulness programs in reducing behavioural problems among community youth. The data were collected at baseline, intervention completion and 1-month follow-up (Spring 2021 to Spring 2022) in Ontario, Canada (n=117, mean age=16.82, male=22%, non-White=21%). Results: The average score for conduct problems was within the normal range, while the average score for hyperactivity was considered borderline at baseline. Accounting for other types of screen time, time spent playing video games was significantly associated with increased conduct problems (ß= 1.75, p=.03), albeit rendering non-significant after correcting for multiple comparisons. The online mindfulness program was significantly associated with reduced hyperactivity, controlling for baseline mental health, age, sex and screen time. Conclusion: The current findings suggest a 12-week online mindfulness program may play a positive role in reducing hyperactivity even when accounting for screen time. Our findings advocate the evidence base on the efficacy of MBI in managing hyperactivity.

12.
Artículo en Inglés | MEDLINE | ID: mdl-38564365

RESUMEN

RATIONALE: Observational studies suggest that high-dose isoniazid may be efficacious in treating multidrug-resistant tuberculosis (MDR-TB). However, its activity against Mycobacterium tuberculosis (M.tb) with katG mutations (which typically confer high-level resistance) is not established. OBJECTIVE: To characterize early bactericidal activity (EBA) of high-dose isoniazid in patients with tuberculosis caused by katG-mutated M.tb. METHODS: A5312 was a Phase 2A randomized, open-label trial. Participants with tuberculosis caused by katG-mutated M.tb were randomized to receive 15 or 20 mg/kg isoniazid daily for 7 days. Daily sputum samples were collected for quantitative culture. Intensive PK sampling was performed on day 6. Data were pooled across all A5312 participants for analysis (drug-sensitive, inhA-mutated, and katG-mutated M.tb). EBA was determined using nonlinear mixed-effects modelling. RESULTS: Of 80 treated participants, 21 had katG-mutated M.tb. Isoniazid PK was best described by a two-compartment model with an effect of NAT2 acetylator phenotype on clearance. Model-derived Cmax and AUC in the 15 and 20 mg/kg groups were 15.0 and 22.1 mg/L and 57.6 and 76.8 mg∙h/L, respectively. Isoniazid bacterial kill was described using an effect compartment and a sigmoidal Emax relationship. Isoniazid potency against katG-mutated M.tb was approximately 10-fold lower than against inhA-mutated M.tb. The highest dose (20 mg/kg) did not demonstrate measurable EBA, except in a subset of slow NAT2 acetylators (who experienced the highest concentrations). There were no grade 3 or higher drug-related adverse events. CONCLUSIONS: This study found negligible bactericidal activity of high-dose isoniazid (15-20 mg/kg) in the majority of participants with tuberculosis caused by katG-mutated M.tb. Clinical trial registration available at www. CLINICALTRIALS: gov, ID: NCT01936831.

13.
Ecotoxicol Environ Saf ; 276: 116294, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38574646

RESUMEN

Particulate matter (PM), released into the air by a variety of natural and human activities, is a key indicator of air pollution. Although PM is known as the extensive health hazard to affect a variety of illness, few studies have specifically investigated the effects of PM10 exposure on schizophrenic development. In the present study, we aimed to investigate the impact of PM10 on MK-801, N-methyl-D-aspartate (NMDA) receptor antagonist, induced schizophrenia-like behaviors in C57BL/6 mouse. Preadolescent mice were exposed PM10 to 3.2 mg/m3 concentration for 4 h/day for 2 weeks through a compartmentalized whole-body inhalation chamber. After PM10 exposure, we conducted behavioral tests during adolescence and adulthood to investigate longitudinal development of schizophrenia. We found that PM10 exacerbated schizophrenia-like behavior, such as psychomotor agitation, social interaction deficits and cognitive deficits at adulthood in MK-801-induced schizophrenia animal model. Furthermore, the reduced expression levels of brain-derived neurotrophic factor (BDNF) and the phosphorylation of BDNF related signaling molecules, extracellular signal-regulated kinase (ERK) and cAMP response element-binding protein (CREB), were exacerbated by PM10 exposure in the adult hippocampus of MK-801-treated mice. Thus, our present study demonstrates that exposure to PM10 in preadolescence exacerbates the cognitive impairment in animal model of schizophrenia, which are considered to be facilitated by the decreased level of BDNF through reduced ERK-CREB expression.


Asunto(s)
Factor Neurotrófico Derivado del Encéfalo , Proteína de Unión a Elemento de Respuesta al AMP Cíclico , Maleato de Dizocilpina , Ratones Endogámicos C57BL , Material Particulado , Esquizofrenia , Transducción de Señal , Animales , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Esquizofrenia/inducido químicamente , Material Particulado/toxicidad , Maleato de Dizocilpina/farmacología , Ratones , Masculino , Transducción de Señal/efectos de los fármacos , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Contaminantes Atmosféricos/toxicidad , Conducta Animal/efectos de los fármacos , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Modelos Animales de Enfermedad , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo
14.
J Inorg Biochem ; 256: 112568, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38678914

RESUMEN

A water-soluble colorimetric chemosensor NHOP ((E)-1-(2-(2-(2-hydroxy-5-nitrobenzylidene)hydrazineyl)-2-oxoethyl)pyridin-1-ium) chloride) was developed for the sequential probing of Cu2+ and S2-. NHOP underwent a color change from pale yellow to colorless in the presence of Cu2+ in pure water. The binding ratio between NHOP and Cu2+ was confirmed to be 1:1 by the Job plot and ESI-MS (electrospray ionization mass spectrometry). The detection limit of NHOP for Cu2+ was calculated as 0.15 µM, which was far below the EPA (Environmental Protection Agency) standard (20 µM). The NHOP-coated test strip was able to easily monitor Cu2+ in real-time. Meanwhile, the NHOP-Cu2+ complex reverted from colorless to pale yellow in the presence of S2- through the demetallation. The stoichiometric ratio between NHOP-Cu2+ and S2- was determined to be 1:1 by analyzing the Job plot and ESI-MS. The detection limit of NHOP-Cu2+ for S2- was calculated as 0.29 µM, which was very below the WHO (World Health Organization) guideline (14.7 µM). NHOP successfully achieved the quantification for Cu2+ and S2- in water samples. NHOP could work as a sequential probe for Cu2+ and S2- at the biological pH range (7.0-8.4). Moreover, NHOP could successively probe Cu2+ and S2- at least three cycles because of its reversible property. The detection mechanisms of NHOP for Cu2+ and NHOP-Cu2+ for S2- were demonstrated with Job plot, ESI-MS, and DFT (density functional theory) calculations. Therefore, NHOP could work as an efficient sequential probe for Cu2+ and S2- in environmental systems.


Asunto(s)
Colorimetría , Cobre , Cobre/análisis , Cobre/química , Colorimetría/métodos , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/química , Agua/química , Espectrometría de Masa por Ionización de Electrospray/métodos , Límite de Detección
16.
PLoS One ; 19(4): e0302164, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38626126

RESUMEN

While COVID-19 impacted all aspects of health care and patient treatment, particularly for patients with mental health/substance use (MH/SU) concerns, research has suggested a concerning increase in the use of restraint and seclusion (R/S) interventions, although results vary depending on facility type and patient population. Thus, the present study sought to explore COVID-related changes in the use of R/S interventions among patients presenting to Ontario emergency departments (EDs) with MH/SU complaints. To determine whether temporal and clinical factors were associated with changes in R/S use during COVID, binary logistic regression models were computed using data from the National Ambulatory Care Reporting System database. We then compared both prevalence rates and probability of an R/S event occurring during an ED visit in Ontario before and after the onset of COVID. The number of ED visits during which an R/S event occurred for patients presenting with MH/SU concerns increased by 9.5%, while their odds of an R/S event occurring during an ED visit increased by 23% in Ontario after COVID onset. Similarly, R/S event probability increased for patients presenting with MH/SU concerns after COVID onset (0.7% - 21.3% increase), particularly during the first wave, with the greatest increases observed for concerns associated with increased restraint risk pre-COVID. R/S intervention use increased substantially for patients presenting to Ontario EDs with MH/SU concerns during the first wave of COVID when the strain on healthcare system and uncertainty about the virus was arguably greatest. Patients with concerns already associated with increased R/S risk also showed the largest increases in R/S probability, suggesting increased behavioural issues during treatment among this population after COVID onset. These results have the potential to inform existing policies to mitigate risks associated with R/S intervention use during future public health emergencies and in general practice.


Asunto(s)
COVID-19 , Trastornos Relacionados con Sustancias , Humanos , Ontario/epidemiología , Pandemias , COVID-19/epidemiología , Trastornos Relacionados con Sustancias/epidemiología , Servicio de Urgencia en Hospital
17.
J Toxicol Environ Health A ; 87(9): 371-380, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38440899

RESUMEN

Exposure to microplastics may be associated with damage of immune system. Polypropylene microplastics (PP-MPs) with a wide range of beneficial applications have not been extensively studied with respect to the immune system. The aim of this investigation is to examine the influence of two different sizes of PP-MPs (5.2 and 23.9 µm diameter) on immune system components in ICR mice. PP-MPs were administered orally to female and male mice at 0 (corn oil vehicle), 500, 1000, or 2000 mg/kg/d for single and daily for 4-week repeated toxicity test, respectively. No significant differences were observed in number of thymic CD4+, CD8+, CD4+CD8+ T lymphocytes, splenic helper T cells, cytotoxic T cells, and B cells. The ratio of interferon-γ to interleukin-4 in culture supernatants from activated splenocytes ex vivo (48 hr) was lower in females which were repeatedly administered with PP-MPs compared to vehicle irrespective of PP-MPs size and dose. In contrast, the opposite trend was observed in males. Production of tumor necrosis factor-α was upregulated in females that were repeatedly exposed to PP-MPs. The serum IgG2a/IgG1 ratio was lowered in female receiving large-size PP-MPs. Data suggest that immune disturbances resulting in predominant type-2 helper T cell reactivity may occur in mice, especially in females, when repeatedly exposed to PP-MPs. Further investigations with longer exposure periods are necessary to determine the immunotoxicities attributed to PP-MPs.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Ratones , Masculino , Femenino , Animales , Ratones Endogámicos ICR , Plásticos , Polipropilenos/toxicidad , Bazo
18.
Am J Dent ; 37(1): 3-8, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38458975

RESUMEN

PURPOSE: To evaluate the effectiveness of whitening toothpaste in restoring tooth color after coffee staining and its potential impact on enamel surfaces compared with regular toothpaste. METHODS: Bovine tooth enamel specimens were prepared and stained with coffee solutions before undergoing brushing simulation with different toothpaste slurries (whitening, regular, reference). For precise evaluation, spectrophotometric measurements were taken at intervals to assess color changes using the CIELAB (Commission Internationale de l'Éclairage Lab*) color space. Additionally, profilometric measurements were taken to determine the impact of toothpaste type on the roughness and abraded depth of the enamel surface. To understand the effects of toothpaste and brushing on color change, surface roughness, and abraded depth, while also considering correlations between these factors, the findings were analyzed using mixed-effects models. RESULTS: The whitening toothpaste group demonstrated the highest recovery rate (71%) after 10,000 brushstrokes, followed by the regular toothpaste group (48%) and the reference slurry group (43%). The mixed-effects model analysis revealed that the reference group had a smaller change in lightness (ΔL) than those in the regular toothpaste group. The whitening toothpaste group showed a greater change in lightness on average than those in the regular toothpaste group, with an increase in lightness as the number of brushstrokes increased. According to the roughness and abraded depth data, the whitening toothpaste group was least affected by brushing, while the reference and regular toothpaste groups showed higher levels of roughness and abraded depth at all intervals. CLINICAL SIGNIFICANCE: Gaining a thorough understanding of the effectiveness of whitening toothpaste and its impact on the enamel surface plays a crucial role in refining toothpaste formulations and advancing tooth whitening techniques in dental care.


Asunto(s)
Blanqueamiento de Dientes , Decoloración de Dientes , Animales , Bovinos , Humanos , Pastas de Dientes/uso terapéutico , Pastas de Dientes/farmacología , Café , Esmalte Dental , Decoloración de Dientes/tratamiento farmacológico , Decoloración de Dientes/prevención & control , Blanqueamiento de Dientes/métodos , Cepillado Dental , Atención Odontológica , Color
19.
RSC Adv ; 14(12): 8578-8582, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38487519

RESUMEN

4-Nonylphenol (4NP) is concerning due to its growing presence and endocrine-disrupting nature, raising concerns about its impact on health. In this study 124I-labeled 4NP was synthesized for in vivo tracing. Positron emission tomography imaging and biodistribution studies showed significant accumulation in various tissues after oral or intraperitoneal administration, emphasizing its intricate distribution and potential long-term effects, crucial for future risk assessments.

20.
Front Vet Sci ; 11: 1298215, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38528871

RESUMEN

Brain perfusion allows for the evaluation of cerebral hemodynamics, particularly in brain infarcts and tumors. Computed tomography (CT) perfusion (CTP) provides reliable data; however, it has a limited scan field of view and radiation exposure. Magnetic resonance (MR) perfusion provides detailed imaging of small structures and a wide scan field of view. However, no study has compared CTP and MR perfusion and assessed the correlation between the perfusion parameters measured using CTP and MR perfusion. The aim of the present study was to assess the correlation and agreement of the cerebral perfusion derived from dynamic susceptibility contrast (DSC)-MRI and CTP in dogs. In this crossover design study, the cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time, and time to peak were measured in the temporal cerebral cortex, caudate nucleus, thalamus, piriform lobe, and hippocampus using CTP and DSC-MRI in six healthy beagle dogs and a dog with a pituitary tumor. On the color map of healthy beagles, blood vessels and the perivascular brain parenchyma appeared as red-green, indicating high perfusion, and the areas distant from the vessels appeared as green-blue, indicating low perfusion levels in CTP and DSC-MRI. CTP parameters were highest in the piriform lobe (CBF = 121.11 ± 12.78 mL/100 g/min and CBV = 8.70 ± 2.04 mL/100 g) and lowest in the thalamus (CBF = 63.75 ± 25.24 mL/100 g/min and CBV = 4.02 ± 0.55 mL/100 g). DSC-MRI parameters were also highest in the piriform lobe (CBF = 102.31 ± 14.73 mL/100 g/min and CBV = 3.17 ± 1.23 mL/100 g) and lowest in the thalamus (CBF = 37.73 ± 25.11 mL/100 g/min and CBV = 0.81 ± 0.44 mL/100 g) although there was no statistical correlation in the quantitative perfusion parameters between CTP and DSC-MRI. In a dog with a pituitary tumor, the color map of the tumor appeared as a red scale, indicating high perfusion and higher CBF and CBV on CTP (149 mL/100 g and 20 mL/100 g/min) and on DSC-MRI (116.3 mL/100 g and 15.32 mL/100 g/min) compared to those measured in healthy dogs. These findings indicate that DSC-MRI and CTP maps exhibit comparability and interchangeability in the assessment of canine brain perfusion.

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