COVID-19 (SARS-CoV-2) mRNA vaccination does not affect basal sex hormone levels (follicle-stimulating hormone, luteinizing hormone, estradiol) in reproductive-age women.

Objective: People vaccinated with the coronavirus disease 2019 (COVID-19) (severe acute respiratory syndrome coronavirus-2 [SARS-CoV-2]) mRNA vaccine have reported experiencing various adverse effects. For instance, reproductive-age women have presented with complaints of abnormal uterine bleeding or menstrual cycle changes. We speculated that differences in basal sex hormone levels before and after vaccination may be present in women who experienced irregular bleeding or menstrual cycle changes; thus, this study aimed to investigate the differences in basal sex hormone levels of women before and after two doses of SARS-CoV-2 mRNA vaccination. Methods: This retrospective study included patients who received SARS-CoV-2 mRNA vaccines between January 2021 and February 2022 at a single center. In an outpatient setting, patients were queried regarding their menstrual cycle, the date of SARS-CoV-2 mRNA vaccination, vaccination type, and vaccination side effects. Differences in basal hormone levels (menstrual cycle days 2-3, follicle-stimulating hormone [FSH], luteinizing hormone [LH], and estradiol) before and after vaccination were compared. Results: Among the 326 patients, patients with no laboratory records of the hormones were excluded. The median time interval between SARS-CoV-2 mRNA vaccination and the laboratory test day was 79 days (interquartile range, 44 to 127). A comparative analysis of these hormones before and after vaccination revealed no significant differences. Subgroup analyses based on age and reported adverse events also found no statistically significant differences. Conclusion: This study showed no significant differences in basal hormone levels (FSH, LH, and estradiol) before and after SARS-CoV-2 mRNA vaccination.

The Beneficial Roles of Sargassum spp. in Skin Disorders.

As the body's largest organ, the skin is located at the internal and external environment interface, serving as a line of defense against various harmful stressors. Recently, marine-derived physiologically active ingredients have attracted considerable attention in the cosmeceutical industry due to their beneficial effects on skin health. Sargassum, a genus of brown macroalgae, has traditionally been consumed as food and medicine in several countries and is rich in bioactive compounds such as meroterpenoids, sulfated polysaccharides, fucoidan, fucoxanthin, flavonoids, and terpenoids. Sargassum spp. have various beneficial effects on skin disorders. They help with atopic dermatitis by improving skin barrier protection and reducing inflammation. Several species show potential in treating acne by inhibiting bacterial growth and reducing inflammation. Some species, such as Sargassum horneri, demonstrate antiallergic effects by modulating mast cell activity. Certain Sargassum species exhibit anticancer activity by inhibiting tumor growth and promoting apoptosis, and some species help with wound healing by promoting angiogenesis and reducing oxidative stress. Overall, Sargassum spp. demonstrate potential for treating and managing various skin conditions. Therefore, the bioactive compounds of Sargassum spp. may be natural ingredients with a wide range of functional properties for preventing and treating skin disorders. The present review focused on the various biological effects of Sargassum extracts and derived compounds on skin disorders.

Genetic Correlation of miRNA Polymorphisms and STAT3 Signaling Pathway with Recurrent Implantation Failure in the Korean Population.

The growing prevalence of in vitro fertilization-embryo transfer procedures has resulted in an increased incidence of recurrent implantation failure (RIF), necessitating focused research in this area. STAT3, a key factor in maternal endometrial remodeling and stromal proliferation, is crucial for successful embryo implantation. While the relationship between STAT3 and RIF has been studied, the impact of single nucleotide polymorphisms (SNPs) in miRNAs, well-characterized gene expression modulators, on STAT3 in RIF cases remains uncharacterized. Here, we investigated 161 RIF patients and 268 healthy control subjects in the Korean population, analyzing the statistical association between miRNA genetic variants and RIF risk. We aimed to determine whether SNPs in specific miRNAs, namely miR-218-2 rs11134527 G>A, miR-34a rs2666433 G>A, miR-34a rs6577555 C>A, and miR-130a rs731384 G>A, were significantly associated with RIF risk. We identified a significant association between miR-34a rs6577555 C>A and RIF prevalence (implantation failure [IF] ≥ 2: adjusted odds ratio [AOR] = 2.264, 95% CI = 1.007-5.092, p = 0.048). These findings suggest that miR-34a rs6577555 C>A may contribute to an increased susceptibility to RIF. However, further investigations are necessary to elucidate the precise mechanisms underlying the role of miR-34a rs6577555 C>A in RIF. This study sheds light on the genetic and molecular factors underlying RIF, offering new avenues for research and potential advancements in the diagnosis and treatment of this complex condition.

Association of Polymorphisms in FSHR, INHA, ESR1, and BMP15 with Recurrent Implantation Failure.

Recurrent implantation failure (RIF) refers to two or more unsuccessful in vitro fertilization embryo transfers in the same individual. Embryonic characteristics, immunological factors, and coagulation factors are known to be the causes of RIF. Genetic factors have also been reported to be involved in the occurrence of RIF, and some single nucleotide polymorphisms (SNPs) may contribute to RIF. We examined SNPs in FSHR, INHA, ESR1, and BMP15, which have been associated with primary ovarian failure. A cohort of 133 RIF patients and 317 healthy controls consisting of all Korean women was included. Genotyping was performed by Taq-Man genotyping assays to determine the frequency of the following polymorphisms: FSHR rs6165, INHA rs11893842 and rs35118453, ESR1 rs9340799 and rs2234693, and BMP15 rs17003221 and rs3810682. The differences in these SNPs were compared between the patient and control groups. Our results demonstrate a decreased prevalence of RIF in subjects with the FSHR rs6165 A>G polymorphism [AA vs. AG adjusted odds ratio (AOR) = 0.432; confidence interval (CI) = 0.206-0.908; p = 0.027, AA+AG vs. GG AOR = 0.434; CI = 0.213-0.885; p = 0.022]. Based on a genotype combination analysis, the GG/AA (FSHR rs6165/ESR1 rs9340799: OR = 0.250; CI = 0.072-0.874; p = 0.030) and GG-CC (FSHR rs6165/BMP15 rs3810682: OR = 0.466; CI = 0.220-0.987; p = 0.046) alleles were also associated with a decreased RIF risk. Additionally, the FSHR rs6165GG and BMP15 rs17003221TT+TC genotype combination was associated with a decreased RIF risk (OR = 0.430; CI = 0.210-0.877; p = 0.020) and increased FSH levels, as assessed by an analysis of variance. The FSHR rs6165 polymorphism and genotype combinations are significantly associated with RIF development in Korean women.

Cross-reactive humoral immunity of clade 2 Oka and MAV/06 strain-based varicella vaccines against different clades of varicella-zoster virus.

The currently used Japanese Oka and Korean MAV/06-attenuated varicella vaccine strains belong to clade 2 genotype varicella-zoster viruses (VZV). More than seven clades of VZV exist worldwide. In this study, we investigated the cross-reactivity of antibodies induced by clade 2 genotype vaccines against VZV strains belonging to clades 1, 2, 3, and 5 using a fluorescent antibody to membrane antigen (FAMA) test. Among 59 donors, 29 were vaccinated with the MAV/06 strain MG1111 (GC Biopharma, South Korea) and the other 30 were vaccinated with the Oka strain VARIVAX (Merck, USA). The sera were titrated using FAMA tests prepared with six different VZV strains (two vaccine strains, one wild-type clade 2 strain, and one each of clade 1, 3, and 5 strains). The ranges of geometric mean titers (GMTs) of FAMA against six different strains were 158.7-206.5 and 157.6-238.9 in MG1111 and VARIVAX groups, respectively. GMTs of the MG1111 group against all six strains were similar; however, GMTs of the VARIVAX group showed differences of approximately 1.5-fold depending on the strains. Nevertheless, the GMTs of the two vaccinated groups for the same strain were not significantly different. These results suggest that both MG1111 and VARIVAX vaccinations induce cross-reactive humoral immunity against other clades of VZV.

Septotemporal variations in hippocampal value and outcome processing.

A large body of evidence indicates functional variations along the hippocampal longitudinal axis. To investigate whether and how value and outcome processing vary between the dorsal (DH) and the ventral hippocampus (VH), we examined neuronal activity and inactivation effects of the DH and VH in mice performing probabilistic classical conditioning tasks. Inactivation of either structure disrupts value-dependent anticipatory licking, and value-coding neurons are found in both structures, indicating their involvement in value processing. However, the DH neuronal population increases activity as a function of value, while the VH neuronal population is preferentially responsive to the highest-value sensory cue. Also, signals related to outcome-dependent value learning are stronger in the DH. VH neurons instead show rapid responses to punishment and strongly biased responses to negative prediction error. These findings suggest that the DH faithfully represents the external value landscape, whereas the VH preferentially represents behaviorally relevant, salient features of experienced events.

The teaching of geriatric dentistry in South Korean dental schools.

OBJECTIVE: The purpose of this study was to investigate the curriculum of geriatric dentistry for undergraduates in Korean dental schools. BACKGROUND: For development purposes, it was necessary to compare geriatric dentistry education programmes in South Korea to programmes in the United States and Europe. METHODS: The most recent curriculum and related information on geriatric dentistry at the undergraduate level in all 11 dental schools in South Korea were collected by both official letter and e-mail. A symposium for gathering expert opinions to improve geriatric dentistry education in South Korea was also held. The collected data were analysed, and the expert opinions at the symposium were summarised. RESULTS: Six of 11 schools had a didactic course as compulsory and three schools as elective. The course was usually conducted as a form of integrated lectures, and the level of standardisation of lecture content was very low. There were no topics for older people who cannot access dental clinics due to functional frailty or disability. No dental school-affiliated hospitals had an independent department for geriatric dentistry. No schools provided clinical teaching for geriatric dentistry. There were no outreach programmes for geriatric dentistry. CONCLUSIONS: The educational curriculum for geriatric dentistry in South Korea was insufficient to cope with social and demographic changes. Curriculum content should include clinical practice education and needs to be focused on frail and dependent older adult patients. An essential educational curriculum and core competency for geriatric dentistry should be prepared.

Radiologic Findings of Polyacrylamide Gel Mammoplasty and Its Complications: A Report of Four Case Series and Review of Literature.

Polyacrylamide gel (PAAG) has been used for augmentation mammoplasty in certain countries, such as China or Eastern European countries. However, owing to various complications, its use is currently banned in most countries. Nevertheless, because of the migratory stream of female from these countries, we also encounter patients with PAAG mammoplasty in Korea. Owing to the various imaging features of PAAG mammoplasty, it may interfere with the identification of malignancy or other pathologic conditions. Therefore, it is important to identify the imaging findings related to PAAG mammoplasty. However, there is limited literature on the radiologic findings of complications related to PAAG mammoplasty in Korea. Herein we report four cases of PAAG mammoplasty, the complications faced, and depict various radiologic features through multimodality imaging.

Molybdenum Carbide Anchored on N,S Co-Doped Carbon Composite Derived from Lignosulfonate as a High Performance Electrocatalyst for Hydrogen Evolution Reaction.

A composite of Mo2C nanoparticles dispersed onto a nitrogen and sulfur co-doped carbon scaffold (Mo2C/N,S-C) was prepared by a simple and environmentally friendly method of one-pot annealing of MoCl5, urea, and lignosulfonate under a N2 atmosphere at 700 °C. Lignosulfonate, a by-product of the sulfite pulping process, was employed as a feedstock to fabricate the S-doped carbon scaffold and carbide simultaneously, and urea acted as a nitrogen source for N-doping to carbon. The as-prepared Mo2C/N,S-C catalyst showed high performance for the hydrogen evolution reaction (HER), with a small overpotential of 105 mV at 10 mAcm-2, and good stability for 3000 cycles. The improved HER performance of the Mo2C/N,S-C originated from the interplay between the highly active Mo2C nanoparticles and the N,S co-doped carbon scaffold with its high electrical conductivity and large surface area. Furthermore, N,S co-doping to carbon improved the hydrophilicity of the catalyst surface, thus further enhancing the HER activity.

Children and adolescent patients with goiter and normal thyroid function: US findings related to underlying autoimmune thyroid diseases.

This study was conducted to investigate and compare thyroid ultrasonography (US) findings in children and adolescents with goiter and normal thyroid function with positive or negative thyroid autoimmunity. From 2000 to 2020, we reviewed initial thyroid US images in 33 autoimmune thyroid diseases (AITDs) patients and 52 nonAITD patients. Our review of the images focused on thyroid parenchymal hypoechogenicity and heterogeneous echopattern subdivided into 2 groups according to severity: hypoechogenicity 1 and 2 (HO1 and HO2) and heterogeneity 1 and 2 (HE1 and HE2). HO1 and HE1 were observed more frequently in the nonAITD group (86.5% and 42.3%, respectively), while HO2 and HE2 were observed more frequently in the AITDs group (36.4% and 81.8%, respectively). More patients in the AITDs group showed change of both US groups and thyroid function state within the follow-up periods than in nonAITD group (33.3% and 5.77%, respectively). Children and adolescent AITDs patients showed more severe parenchyma hypoechogenicity and heterogeneous echopattern compared with nonAITD patients with goiter and normal thyroid function.

Inhibitory effects of Centella asiatica (L.) Urban on enlarged prostate through androgen receptor and PI3K/Akt signaling pathways.

Centella asiatica (L.) Urban (C. asiatica) is a traditional herbal medicine that has been used for wound healing and anti-inflammation since ancient times. Various biological effects of C. asiatica ethanolic extract (CAE) were previously reported. However, in our previous study, C. asiatica aqueous extract (CAA) exhibited higher inhibitory activity on benign prostatic hyperplasia (BPH) than CAE. Therefore, the aim of this study was to investigate the effect of CAA on BPH, and elucidate the inhibitory mechanism through in vitro and in vivo experiments as well as metabolite analysis of CAA. A BPH rat model was induced by daily subcutaneous injection of testosterone propionate (TP, 3 mg kg-1) dissolved in corn oil for 4 weeks after castration. The experimental group, the CAA treatment group, was orally administered CAA (100 mg kg-1) for 4 weeks while inducing prostatic hyperplasia. Saw palmetto extract (Saw, 100 mg kg-1) and Finasteride (Fi, 1 mg kg-1) were used as positive controls and were administered orally for 4 weeks. CAA significantly inhibited androgen receptor signaling related factors overexpressed by dihydrotestosterone (DHT) treatment in prostate cell lines. Afterwards, the testosterone-induced BPH model was used to verify the alleviation efficacy of CAA in prostatic hyperplasia. Prostate size and the thickness of the prostate tissue epithelium were significantly decreased in the group treated with CAA compared to those in the BPH group. The results of protein expression in the prostate tissue confirmed that CAA inhibited androgen receptor signaling in BPH and decreased the expression of growth factors. Moreover, CAA suppressed the expression of the PI3K/Akt pathway and cell proliferation-related factors compared to the BPH group. Taken together, these results indicate that CAA improves the inhibitory efficacy of BPH by inhibiting the androgen receptor and PI3K/Akt pathways, suggesting that CAA may be a promising candidate for biopharmaceutical formulations of BPH.

A study on the mental health of students at a medical school during COVID-19 outbreak: a retrospective study.

BACKGRUOUND: In this study, the degree of anxiety, depression, and stress caused by coronavirus disease 2019 (COVID-19) was identified, as well as the need for psychological prevention measures among medical students in the Daegu region that was designated the first special disaster area due to the spread of COVID-19. METHODS: The subjects of this study were 318 medical students in Daegu who voluntarily participated in an online test using the Hospital Anxiety and Depression Scale and Impact of Event Scale-Revised Korean version. As a result of the test, risk students received immediate telephone counseling, and the effect of this telephone counseling was analyzed. RESULTS: There were no differences in depression, anxiety, or stress according to gender and grade. As a result of immediate telephone counseling for risk students, significant differences were found in depression, anxiety, and stress, and the counseling was found to be effective. CONCLUSION: For medical students who are easily exposed to stress, the importance of psychological prevention measures and effectiveness of non-face-to-face counseling should be recognized. In the field of medical education, we must do our best to build a system that can be used immediately at the appropriate time for these programs.

Wearable CNTs-based humidity sensors with high sensitivity and flexibility for real-time multiple respiratory monitoring.

Sensors, such as optical, chemical, and electrical sensors, play an important role in our lives. While these sensors already have widespread applications, such as humidity sensors, most are generally incompatible with flexible/inactive substrates and rely on conventional hard materials and complex manufacturing processes. To overcome this, we develop a CNT-based, low-resistance, and flexible humidity sensor. The core-shell structured CNT@CPM is prepared with Chit and PAMAM to achieve reliability, accuracy, consistency, and durability, resulting in a highly sensitive humidity sensor. The average response/recovery time of optimized sensor is only less than 20 s, with high sensitivity, consistent responsiveness, good linearity according to humidity rates, and low hysteresis (- 0.29 to 0.30 %RH). Moreover, it is highly reliable for long-term (at least 1 month), repeated bending (over 15,000 times), and provides accurate humidity measurement results. We apply the sensor to smart-wear, such as masks, that could conduct multi-respiratory monitoring in real-time through automatic ventilation systems. Several multi-respiratory monitoring results demonstrate its high responsiveness (less than 1.2 s) and consistent performance, indicating highly desirable for healthcare monitoring. Finally, these automatic ventilation systems paired with flexible sensors and applied to smart-wear can not only provide comfort but also enable stable and accurate healthcare in all environments.

Differing benefits of artificial intelligence-based computer-aided diagnosis for breast US according to workflow and experience level.

PURPOSE: This study evaluated how artificial intelligence-based computer-assisted diagnosis (AICAD) for breast ultrasonography (US) influences diagnostic performance and agreement between radiologists with varying experience levels in different workflows. METHODS: Images of 492 breast lesions (200 malignant and 292 benign masses) in 472 women taken from April 2017 to June 2018 were included. Six radiologists (three inexperienced [<1 year of experience] and three experienced [10-15 years of experience]) individually reviewed US images with and without the aid of AI-CAD, first sequentially and then simultaneously. Diagnostic performance and interobserver agreement were calculated and compared between radiologists and AI-CAD. RESULTS: After implementing AI-CAD, the specificity, positive predictive value (PPV), and accuracy significantly improved, regardless of experience and workflow (all P<0.001, respectively). The overall area under the receiver operating characteristic curve significantly increased in simultaneous reading, but only for inexperienced radiologists. The agreement for Breast Imaging Reporting and Database System (BI-RADS) descriptors generally increased when AI-CAD was used (κ=0.29-0.63 to 0.35-0.73). Inexperienced radiologists tended to concede to AI-CAD results more easily than experienced radiologists, especially in simultaneous reading (P<0.001). The conversion rates for final assessment changes from BI-RADS 2 or 3 to BI-RADS higher than 4a or vice versa were also significantly higher in simultaneous reading than sequential reading (overall, 15.8% and 6.2%, respectively; P<0.001) for both inexperienced and experienced radiologists. CONCLUSION: Using AI-CAD to interpret breast US improved the specificity, PPV, and accuracy of radiologists regardless of experience level. AI-CAD may work better in simultaneous reading to improve diagnostic performance and agreement between radiologists, especially for inexperienced radiologists.

Ethyl Gallate Dual-Targeting PTPN6 and PPARγ Shows Anti-Diabetic and Anti-Obese Effects.

The emergence of the high correlation between type 2 diabetes and obesity with complicated conditions has led to the coinage of the term "diabesity". AMP-activated protein kinase (AMPK) activators and peroxisome proliferator-activated receptor (PPARγ) antagonists have shown therapeutic activity for diabesity, respectively. Hence, the discovery of compounds that activate AMPK as well as antagonize PPARγ may lead to the discovery of novel therapeutic agents for diabesity. In this study, the knockdown of PTPN6 activated AMPK and suppressed adipogenesis in 3T3-L1 cells. By screening a library of 1033 natural products against PTPN6, we found ethyl gallate to be the most selective inhibitor of PTPN6 (Ki = 3.4 µM). Subsequent assay identified ethyl gallate as the best PPARγ antagonist (IC50 = 5.4 µM) among the hit compounds inhibiting PTPN6. Ethyl gallate upregulated glucose uptake and downregulated adipogenesis in 3T3-L1 cells as anticipated. These results strongly suggest that ethyl gallate, which targets both PTPN6 and PPARγ, is a potent therapeutic candidate to combat diabesity.

Ultrasonographic diagnosis and surgical outcomes of adnexal masses in children and adolescents.

This study aimed to evaluate the incidence, clinical diagnosis, surgical treatment, and histopathological findings of adnexal masses in children and adolescents. This retrospective study included patients aged < 20 years who were diagnosed with adnexal masses between January 2005 and December 2018 at the Konkuk University Medical Center. Adnexal masses were diagnosed in 406 patients. The mean age of patients was 17.3 years at the time of diagnosis. The primary presenting symptoms and signs were abdominal pain (81.4%), mass per abdomen (13.7%), dysmenorrhea (3.4%), incidental finding (2%), and abdominal distention (0.5%). In total, 204 patients underwent surgery for adnexal masses, and 202 patients were observed without surgery. Histopathological examination revealed 110 benign neoplasms, 72 non-neoplastic lesions, 3 ectopic pregnancies, 3 tubo-ovarian abscesses, 7 borderline malignant tumors, and 9 non-epithelial ovarian malignant tumors. Abdominal pain was the most common reason for hospital visits and surgery in adolescents and young women with adnexal masses. The ultrasonographic diagnosis was consistent with the histopathological diagnosis. In recent years, the use of minimally invasive surgery such as laparoscopy and robotic, has increased in young patients with adnexal masses.

Humoral and Cellular Responses to COVID-19 Vaccines in SARS-CoV-2 Infection-Naïve and -Recovered Korean Individuals.

In the face of a global COVID-19 vaccine shortage, an efficient vaccination strategy is required. Therefore, the immunogenicity of single or double COVID-19 vaccination doses (ChAdOX1, BNT162b2, or mRNA-1273) of SARS-CoV-2-recovered individuals was compared to that of unvaccinated individuals with SARS-CoV-2 infection at least one year post-convalescence. Moreover, the immunogenicity of SARS-CoV-2-naïve individuals vaccinated with a complete schedule of Ad26.CoV2.S, ChAdOX1, BNT162b2, mRNA-1273, or ChAdOX1/BNT162b2 vaccines was evaluated. Anti-SARS-CoV-2 S1 IgG antibody (S1-IgG), pseudotyped virus-neutralizing antibody titer (pVNT50), and IFN-γ ELISpot counts were measured. Humoral immune responses were significantly higher in vaccinated than in unvaccinated recovered individuals, with a 43-fold increase in the mean pVNT50 values. However, there was no significant difference in the pVNT50 and IFN-γ ELISpot values between the single- and double-dose regimens. In SARS-CoV-2-naïve individuals, antibody responses varied according to the vaccine type: BNT162b2 and mRNA-1273 induced similar levels of S1-IgG to those observed in vaccinated, convalescent individuals; in contrast, pVNT50 was much lower in SARS-CoV-2-naïve vaccinees than in vaccinated recovered individuals. Therefore, a single dose of ChAdOX1, BNT162b2, or mRNA-1273 vaccines would be a good alternative for recovered individuals instead of a double-dose regimen.

Heat-Killed Enterococcus faecalis EF-2001 Attenuate Lipid Accumulation in Diet-Induced Obese (DIO) Mice by Activating AMPK Signaling in Liver.

To explore the inhibitory mechanism of heat-killed Enterococcus faecalis, EF-2001 on hepatic lipid deposition, a diet-induced obese (DIO) animal model was established by high-fat diet (HFD). The DIO C57BL/6 mice were divided into four groups: the normal group without HFD (ND, n = 8), obesity group (HFD, n = 8), experimental group (HFD + EF-2001, 200 mg/kg, n = 8), and positive control group (HFD + Orlistat, 60 mg/kg, n = 8). After 4 weeks, liver and adipose tissue were fixed in 10% paraformaldehyde, followed by embedding in paraffin for tissue sectioning. The differences in body mass, body fat ratio, fatty cell area, and lipid profiling of the liver (TC, LDL, and HDL) were also determined. Moreover, Western blot was performed to analyze the expression of lipid accumulation-related proteins, including AMPK, PPARγ, SREBP-1, ACC, and FAS. Compared with the HFD group, the HFD + EF-2001 group exhibited decreased fat mass, liver index, adipocyte area, TC, and LDL, and an increased level of HDL. The results of liver hematoxylin and eosin (H&E), and oil red O staining showed that the mice in each intervention group were improved on hepatic lipid accumulation, and the mice in the HFD + EF-2001 group were the most similar to those in the normal group when compared with the HFD group. From the Western blot results, we proved that EF-2001 activated the AMPK signaling pathway. EF-2001 significantly upregulated the expressions of p-AMPK and p-ACC and downregulated PPARγ, SREBP-1, and FAS in murine liver. Taken together, these results suggest that EF-2001 decrease lipid accumulation in the DIO model mice through the AMPK pathway and ameliorate liver damage by HFD.

Electrical and thermal stimulus-responsive nanocarbon-based 3D hydrogel sponge for switchable drug delivery.

Smart hydrogels that are responsive to various external (e.g. electrical and/or thermal) stimulation have become increasingly popular in recent years for simple, rapid, and precise drug delivery that can be controlled and turned on or off with external stimuli. For such a switchable drug delivery material, highly homogeneous dispersion and distribution of the hydrophobic, electrically conductive nanomaterials throughout a hydrophilic three-dimensional (3D) hydrogel network remains a challenge and is essential for achieving well-connected electrical and thermal conducting paths. Herein we developed electrical and thermal stimulus-responsive 3D hydrogels based on (i) carbon nanotubes (CNTs) as the core unit and an electrical/thermal conductor, (ii) chitosan (Chit) as the shell unit and a hydrophilic dispersant, and (iii) poly(NIPAAm-co-BBVIm) (pNIBBIm) as the drug carrier and a temperature-responsive copolymer. By formulating the CNT-core and Chit-shell units and constructing a CNT sponge framework, uniform distribution and 3D connectivity of the CNTs were improved. The 3D hydrogel based on the CNT sponge, namely the 3D frame CNT-Chit/pNIBBIm hydrogel, delivered approximately 37% of a drug, ketoprofen used for the treatment of musculoskeletal pain, during about 30% shrinkage after electrical and thermal switches on/off and exhibited the best potential for future use in a smart transdermal drug delivery system. The physicochemical, mechanical, electrical, thermal, and biocompatible characteristics of this nanocarbon-based 3D frame hydrogel led to remarkable electrical and thermal stimulus-responsive properties capable of developing an excellent controllable and switchable drug delivery platform for biomedical engineering and medicine applications.