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1.
J Affect Disord ; 2024 Aug 24.
Article in English | MEDLINE | ID: mdl-39187187

ABSTRACT

OBJECTIVE: This study is to investigate the role of gut microbiota transmission in the development of anxiety/depression in offspring exposed to maternal depression. METHOD: Offspring rats were cohabitated with their depressed mother or father rats (which exposed to chronic unpredictable mild stress (CUMS)) for 2, 4, and 6 months, the anxiety- and depression-like behaviors, and interaction/caring activities between mother/father and their pups were detected. The gut microbiota composition and its relationship with behaviors were analyzed. Fecal microbiota transplantation (FMT) was performed to establish the gut microbiota of depressed/normal mother rats in the offspring rats to further confirm the role of "depressive gut microbiota" transmission in mediating the anxiety/depression in the pups. RESULTS: Anxiety and depression phenotypes can be transmitted from depressed mother rats to their cohabited offspring. Frequent interaction and gut microbiota assimilation were observed between rat mothers and pups. Remodeling of the gut microbiota in pups by FMT could induce or attenuate anxiety- and depression-like phenotypes depending on the origin of the fecal microbiota. By comparison, the pups cohabitated with depressed father rats showed slighter anxiety and depression. CONCLUSIONS: These data together support that depressed mother can transmit anxiety/depression to their pups through gut microbiota assimilation, which is related to frequent interaction. Our study reinforces the importance of mental health of mothers in preventing the occurrence of childhood anxiety and depression, and pointing out the possibility of remodeling intestinal microbiota as an effective therapy for treating anxiety/depression in children.

2.
ACS Nano ; 18(33): 22194-22207, 2024 Aug 20.
Article in English | MEDLINE | ID: mdl-39116033

ABSTRACT

Monotherapy, especially the use of antibodies targeting vascular endothelial growth factor (VEGF), has shown limitations in treating choroidal neovascularization (CNV) since reactive oxygen species (ROS) also exacerbate CNV formation. Herein, we developed a combination therapy based on a DNA origami platform targeting multiple components of ocular neovascularization. Our study demonstrated that ocular neovascularization was markedly suppressed by intravitreal injection of a rectangular DNA origami sheet modified with VEGF aptamers (Ap) conjugated to an anti-VEGF antibody (aV) via matrix metalloproteinase (MMP)-cleavable peptide linkers in a mouse model of CNV. Typically, the DNA origami-based therapeutic platform selectively accumulates in neovascularization lesions owing to the dual-targeting ability of the aV and Ap, followed by the cleavage of the peptide linker by MMPs to release the antibody. Together, the released antibody and Ap inhibited VEGF activity. Moreover, the residual bare DNA origami could effectively scavenge ROS, reducing oxidative stress at CNV sites and thus maximizing the synergistic effects of inhibiting neovascularization.


Subject(s)
Choroidal Neovascularization , DNA , Vascular Endothelial Growth Factor A , Choroidal Neovascularization/drug therapy , Choroidal Neovascularization/metabolism , Animals , Mice , Vascular Endothelial Growth Factor A/metabolism , Vascular Endothelial Growth Factor A/antagonists & inhibitors , Vascular Endothelial Growth Factor A/chemistry , DNA/chemistry , Mice, Inbred C57BL , Reactive Oxygen Species/metabolism , Aptamers, Nucleotide/chemistry , Aptamers, Nucleotide/pharmacology , Matrix Metalloproteinases/metabolism , Matrix Metalloproteinases/chemistry , Antibodies/chemistry
3.
ACS Appl Mater Interfaces ; 16(32): 41855-41868, 2024 Aug 14.
Article in English | MEDLINE | ID: mdl-39093305

ABSTRACT

Inflammation caused by a bacterial infection and the subsequent dysregulation of the host immune-inflammatory response are detrimental to periodontal regeneration. Herein, we present an infection-sensitive scaffold prepared by layer-by-layer assembly of Feraheme-like superparamagnetic iron oxide nanoparticles (SPIONs) on the surface of a three-dimensional-printed polylactic-co-glycolic acid (PLGA) scaffold. The SPION/PLGA scaffold is magnetic, hydrophilic, and bacterial-adhesion resistant. As indicated by gene expression profiling and confirmed by quantitative real-time reverse transcription polymerase chain reaction and flow cytometry analysis, the SPION/PLGA scaffold facilitates macrophage polarization toward the regenerative M2 phenotype by upregulating IL-10, which is the molecular target of repair promotion, and inhibits macrophage polarization toward the proinflammatory M1 phenotype by downregulating NLRP3, which is the molecular target of anti-inflammation. As a result, macrophages modulated by the SPS promote osteogenic differentiation of bone marrow mesenchymal stromal cells (BMSCs) in vitro. In a rat periodontal defect model, the SPION/PLGA scaffold increased IL-10 secretion and decreased NLRP3 and IL-1ß secretion with Porphyromonas gingivalis infection, achieving superior periodontal regeneration than the PLGA scaffold alone. Therefore, this antibacterial SPION/PLGA scaffold has anti-inflammatory and bacterial antiadhesion properties to fight infection and promote periodontal regeneration by immunomodulation. These findings provide an important strategy for developing engineered scaffolds to treat periodontal defects.


Subject(s)
Anti-Bacterial Agents , Macrophages , Polylactic Acid-Polyglycolic Acid Copolymer , Porphyromonas gingivalis , Tissue Scaffolds , Animals , Polylactic Acid-Polyglycolic Acid Copolymer/chemistry , Polylactic Acid-Polyglycolic Acid Copolymer/pharmacology , Macrophages/drug effects , Macrophages/metabolism , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Rats , Porphyromonas gingivalis/drug effects , Tissue Scaffolds/chemistry , Rats, Sprague-Dawley , Magnetic Iron Oxide Nanoparticles/chemistry , Male , Regeneration/drug effects , Phenotype , Mesenchymal Stem Cells/drug effects , Mesenchymal Stem Cells/cytology , Mice
4.
Nat Commun ; 15(1): 5736, 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38982049

ABSTRACT

Excessive exercise is an etiological factor of intervertebral disc degeneration (IVDD). Engineered extracellular vesicles (EVs) exhibit excellent therapeutic potential for disease-modifying treatments. Herein, we fabricate an exercise self-powered triboelectric-responsive microneedle (MN) assay with the sustainable release of optogenetically engineered EVs for IVDD repair. Mechanically, exercise promotes cytosolic DNA sensing-mediated inflammatory activation in senescent nucleus pulposus (NP) cells (the master cell population for IVD homeostasis maintenance), which accelerates IVDD. TREX1 serves as a crucial nuclease, and disassembly of TRAM1-TREX1 complex disrupts the subcellular localization of TREX1, triggering TREX1-dependent genomic DNA damage during NP cell senescence. Optogenetically engineered EVs deliver TRAM1 protein into senescent NP cells, which effectively reconstructs the elimination function of TREX1. Triboelectric nanogenerator (TENG) harvests mechanical energy and triggers the controllable release of engineered EVs. Notably, an optogenetically engineered EV-based targeting treatment strategy is used for the treatment of IVDD, showing promising clinical potential for the treatment of degeneration-associated disorders.


Subject(s)
Extracellular Vesicles , Intervertebral Disc Degeneration , Needles , Nucleus Pulposus , Optogenetics , Intervertebral Disc Degeneration/therapy , Intervertebral Disc Degeneration/metabolism , Extracellular Vesicles/metabolism , Animals , Nucleus Pulposus/metabolism , Optogenetics/methods , Optogenetics/instrumentation , Humans , Phosphoproteins/metabolism , Phosphoproteins/genetics , Cellular Senescence , Exodeoxyribonucleases/metabolism , Exodeoxyribonucleases/genetics , Rats , DNA Damage , Mice , Male , Disease Models, Animal , Rats, Sprague-Dawley
5.
Transl Cancer Res ; 13(6): 3003-3015, 2024 Jun 30.
Article in English | MEDLINE | ID: mdl-38988934

ABSTRACT

Background: Adjuvant chemotherapy (ACT) is a well-recognized and well-established treatment for surgically resected non-small cell lung cancer (NSCLC), but its suitability for elderly patients remains controversial. Further investigation is warranted to guide ACT decisions in this demographic. Methods: We extracted data from the Surveillance, Epidemiology, and End Results (SEER) database, focusing on patients aged 70 years or older who underwent surgical resection for stage IB, II, or III NSCLC as per the 7th edition of the American Joint Committee on Cancer staging system (AJCC 7th edition). Propensity score matching (PSM), Kaplan-Meier analysis, and Cox regression were employed for statistical analyses. Results: There were 503 participants received ACT in this study of 2,000 patients aged 70 or older with stage IB-IIIB NSCLC who underwent surgical resection without preoperative chemotherapy. Overall, ACT did not significantly correlate with extended overall survival (OS) (P=0.07) compared to non-ACT. After 2:1 PSM, the matched cohort comprised 317 non-ACT and 206 ACT recipients. Post-PSM, the ACT group exhibited improved OS (P=0.044) compared to the non-ACT group. Cox regression analysis identified gender, primary tumor site, histologic grade, N stage, and ACT as independent predictors of OS (P<0.05). Subgroup analysis indicated amplified ACT benefits in individuals aged 70-79 years, male, with N1 stage, or those without radiotherapy. Conclusions: ACT may confer benefits to elderly stage IB-IIIB NSCLC patients, particularly those aged 70-79 years, male, and with N1 stage.

6.
Adv Mater ; : e2406235, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-39007254

ABSTRACT

The great challenges for existing wearable pressure sensors are the degradation of sensing performance and weak interfacial adhesion owing to the low mechanical transfer efficiency and interfacial differences at the skin-sensor interface. Here, an ultrasensitive wearable pressure sensor is reported by introducing a stress-concentrated tip-array design and self-adhesive interface for improving the detection limit. A bipyramidal microstructure with various Young's moduli is designed to improve mechanical transfer efficiency from 72.6% to 98.4%. By increasing the difference in modulus, it also mechanically amplifies the sensitivity to 8.5 V kPa-1 with a detection limit of 0.14 Pa. The self-adhesive hydrogel is developed to strengthen the sensor-skin interface, which allows stable signals for long-term and real-time monitoring. It enables generating high signal-to-noise ratios and multifeatures when wirelessly monitoring weak pulse signals and eye muscle movements. Finally, combined with a deep learning bimodal fused network, the accuracy of fatigued driving identification is significantly increased to 95.6%.

7.
Mol Neurobiol ; 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38976127

ABSTRACT

Temporomandibular joint osteoarthritis (TMJOA) is a severe form of temporomandibular joint disorders (TMD), and orofacial inflammatory allodynia is one of its common symptoms which lacks effective treatment. N-methyl-D-aspartate receptor (NMDAR), particularly its subtypes GluN2A and GluN2B, along with gap junctions (GJs), are key players in the mediation of inflammatory pain. However, the precise regulatory mechanisms of GluN2A, GluN2B, and GJs in orofacial inflammatory allodynia during TMJ inflammation still remain unclear. Here, we established the TMJ inflammation model by injecting Complete Freund's adjuvant (CFA) into the TMJ and used Cre/loxp site-specific recombination system to conditionally knock out (CKO) GluN2A and GluN2B in the trigeminal ganglion (TG). Von-frey test results indicated that CFA-induced mechanical allodynia in the TMJ region was relieved in GluN2A and GluN2B deficient mice. In vivo, CFA significantly up-regulated the expression of GluN2A and GluN2B, Gjb1, Gjb2, Gjc2 and Panx3 in the TG, and GluN2A and GluN2B CKO played different roles in mediating the expression of Gjb1, Gjb2, Gjc2 and Panx3. In vitro, NMDA up-regulated the expression of Gjb1, Gjb2, Gjc2 and Panx3 in satellite glial cells (SGCs) as well as promoted the intercellular communication between SGCs, and GluN2A and GluN2B knocking down (KD) altered the expression and function differently. NMDAR regulated Gjb1 and Panx3 through ERK1/2 pathway, and mediated Gjb2 and Gjc2 through MAPK, PKA, and PKC intracellular signaling pathways. These findings shed light on the distinct functions of GluN2A and GluN2B in mediating peripheral sensitization induced by TMJ inflammation in the TG, offering potential therapeutic targets for managing orofacial inflammatory allodynia.

8.
Sci Adv ; 10(30): eado7438, 2024 Jul 26.
Article in English | MEDLINE | ID: mdl-39047093

ABSTRACT

Designing highly efficient orally administrated nanotherapeutics with specific inflammatory site-targeting functions in the gastrointestinal tract for ulcerative colitis (UC) management is a noteworthy challenge. Here, we focused on exploring a specific targeting oral nanotherapy, serving as "one stone," for the directed localization of inflammation and the regulation of redox homeostasis, thereby achieving effects against "two birds" for UC treatment. Our designed nanotherapeutic agent OPNs@LMWH (oxidation-sensitive ε-polylysine nanoparticles at low-molecular weight heparin) exhibited specific active targeting effects and therapeutic efficacy simultaneously. Our results indicate that OPNs@LMWH had high integrin αM-mediated immune cellular uptake efficiency and preferentially accumulated in inflamed tissues. We also confirmed its effectiveness in the treatment experiment of colitis in mice by ameliorating oxidative stress and inhibiting the activation of inflammation-associated signaling pathways while simultaneously bolstering the protective mechanisms of the colonic epithelium. Overall, these findings underscore the compelling dual functionalities of OPNs@LMWH, which enable effective oral delivery to inflamed sites, thereby facilitating precise UC management.


Subject(s)
Colitis, Ulcerative , Homeostasis , Integrins , Nanoparticles , Oxidation-Reduction , Animals , Mice , Colitis, Ulcerative/drug therapy , Colitis, Ulcerative/metabolism , Nanoparticles/chemistry , Administration, Oral , Integrins/metabolism , Oxidative Stress/drug effects , Humans , Disease Models, Animal , Drug Delivery Systems
9.
Am J Obstet Gynecol ; 231(3): 352.e1-352.e16, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38871238

ABSTRACT

BACKGROUND: In recent years, pragmatic metformin use in pregnancy has stretched to include prediabetes mellitus, type 2 diabetes mellitus, gestational diabetes mellitus, and (most recently) preeclampsia. However, with its expanded use, concerns of unintended harm have been raised. OBJECTIVE: This study developed an experimental primate model and applied ultrahigh performance liquid chromatography coupled to triple-quadrupole mass spectrometry for direct quantitation of maternal and fetal tissue metformin levels with detailed fetal biometry and histopathology. STUDY DESIGN: Within 30 days of confirmed conception (defined as early pregnancy), 13 time-bred (timed-mated breeding) Rhesus dams with pregnancies designated for fetal necropsy were initiated on twice-daily human dose-equivalent 10 mg/kg metformin or vehicle control. Pregnant dams were maintained as pairs and fed either a control chow or 36% fat Western-style diet. Metformin or placebo vehicle control was delivered in various treats while the animals were separated via a slide. A cesarean delivery was performed at gestational day 145, and amniotic fluid and blood were collected, and the fetus and placenta were delivered. The fetus was immediately necropsied by trained primate center personnel. All fetal organs were dissected, measured, sectioned, and processed per clinical standards. Fluid and tissue metformin levels were assayed using validated ultrahigh performance liquid chromatography coupled to triple-quadrupole mass spectrometry in selected reaction monitoring against standard curves. RESULTS: Among 13 pregnancies at gestational day 145 with fetal necropsy, 1 dam and its fetal tissues had detectable metformin levels despite being allocated to the vehicle control group (>1 µmol metformin/kg maternal weight or fetal or placental tissue), whereas a second fetus allocated to the vehicle control group had severe fetal growth restriction (birthweight of 248.32 g [<1%]) and was suspected of having a fetal congenital condition. After excluding these 2 fetal pregnancies from further analyses, 11 fetuses from dams initiated on either vehicle control (n=4: 3 female and 1 male fetuses) or 10 mg/kg metformin (n=7: 5 female and 2 male fetuses) were available for analyses. Among dams initiated on metformin at gestational day 30 (regardless of maternal diet), significant bioaccumulation within the fetal kidney (0.78-6.06 µmol/kg; mean of 2.48 µmol/kg), liver (0.16-0.73 µmol/kg; mean of 0.38 µmol/kg), fetal gut (0.28-1.22 µmol/kg; mean of 0.70 µmol/kg), amniotic fluid (0.43-3.33 µmol/L; mean of 1.88 µmol/L), placenta (0.16-1.00 µmol/kg; mean of 0.50 µmol/kg), fetal serum (0.00-0.66 µmol/L; mean of 0.23 µmol/L), and fetal urine (4.10-174.10 µmol/L; mean of 38.5 µmol/L) was observed, with fetal levels near biomolar equivalent to maternal levels (maternal serum: 0.18-0.86 µmol/L [mean of 0.46 µmol/L]; maternal urine: 42.60-254.00 µmol/L [mean of 149.30 µmol/L]). Western-style diet feeding neither accelerated nor reduced metformin bioaccumulations in maternal or fetal serum, urine, amniotic fluid, placenta, or fetal tissues. In these 11 animals, fetal bioaccumulation of metformin was associated with less fetal skeletal muscle (57% lower cross-sectional area of gastrocnemius) and decreased liver, heart, and retroperitoneal fat masses (P<.05), collectively driving lower delivery weight (P<.0001) without changing the crown-rump length. Sagittal sections of fetal kidneys demonstrated delayed maturation, with disorganized glomerular generations and increased cortical thickness. This renal dysmorphology was not accompanied by structural or functional changes indicative of renal insufficiency. CONCLUSION: Our study demonstrates fetal bioaccumulation of metformin with associated fetal growth restriction and renal dysmorphology after maternal initiation of the drug within 30 days of conception in primates. Given these results and the prevalence of metformin use during pregnancy, additional investigation of any potential immediate and enduring effects of prenatal metformin use is warranted.


Subject(s)
Fetal Growth Retardation , Hypoglycemic Agents , Macaca mulatta , Metformin , Metformin/pharmacokinetics , Animals , Female , Pregnancy , Fetal Growth Retardation/metabolism , Hypoglycemic Agents/pharmacokinetics , Kidney/metabolism , Fetus/metabolism , Placenta/metabolism , Amniotic Fluid/metabolism , Models, Animal
10.
Science ; 384(6698): 885-890, 2024 May 24.
Article in English | MEDLINE | ID: mdl-38781365

ABSTRACT

Men or mice with homozygous serine/threonine kinase 33 (STK33) mutations are sterile owing to defective sperm morphology and motility. To chemically evaluate STK33 for male contraception with STK33-specific inhibitors, we screened our multibillion-compound collection of DNA-encoded chemical libraries, uncovered potent STK33-specific inhibitors, determined the STK33 kinase domain structure bound with a truncated hit CDD-2211, and generated an optimized hit CDD-2807 that demonstrates nanomolar cellular potency (half-maximal inhibitory concentration = 9.2 nanomolar) and favorable metabolic stability. In mice, CDD-2807 exhibited no toxicity, efficiently crossed the blood-testis barrier, did not accumulate in brain, and induced a reversible contraceptive effect that phenocopied genetic STK33 perturbations without altering testis size. Thus, STK33 is a chemically validated, nonhormonal contraceptive target, and CDD-2807 is an effective tool compound.


Subject(s)
Contraception , Contraceptive Agents, Male , Protein Kinase Inhibitors , Protein Serine-Threonine Kinases , Small Molecule Libraries , Animals , Humans , Male , Mice , Blood-Testis Barrier/metabolism , Contraceptive Agents, Male/chemistry , Contraceptive Agents, Male/pharmacology , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/chemistry , Protein Serine-Threonine Kinases/antagonists & inhibitors , Protein Serine-Threonine Kinases/chemistry , Small Molecule Libraries/chemistry , Small Molecule Libraries/pharmacology , Testis/drug effects , Contraception/methods , Structure-Activity Relationship
11.
Angew Chem Int Ed Engl ; 63(23): e202405197, 2024 06 03.
Article in English | MEDLINE | ID: mdl-38574245

ABSTRACT

Mammalian cytochrome P450 drug-metabolizing enzymes rarely cleave carbon-carbon (C-C) bonds and the mechanisms of such cleavages are largely unknown. We identified two unusual cleavages of non-polar, unstrained C(sp2)-C(sp3) bonds in the FDA-approved tyrosine kinase inhibitor pexidartinib that are mediated by CYP3A4/5, the major human phase I drug metabolizing enzymes. Using a synthetic ketone, we rule out the Baeyer-Villiger oxidation mechanism that is commonly invoked to address P450-mediated C-C bond cleavages. Our studies in 18O2 and H2 18O enriched systems reveal two unusual distinct mechanisms of C-C bond cleavage: one bond is cleaved by CYP3A-mediated ipso-addition of oxygen to a C(sp2) site of N-protected pyridin-2-amines, and the other occurs by a pseudo-retro-aldol reaction after hydroxylation of a C(sp3) site. This is the first report of CYP3A-mediated C-C bond cleavage in drug metabolism via ipso-addition of oxygen mediated mechanism. CYP3A-mediated ipso-addition is also implicated in the regioselective C-C cleavages of several pexidartinib analogs. The regiospecificity of CYP3A-catalyzed oxygen ipso-addition under environmentally friendly conditions may be attractive and inspire biomimetic or P450-engineering methods to address the challenging task of C-C bond cleavages.


Subject(s)
Cytochrome P-450 CYP3A , Oxygen , Oxygen/chemistry , Oxygen/metabolism , Cytochrome P-450 CYP3A/metabolism , Cytochrome P-450 CYP3A/chemistry , Humans , Molecular Structure , Carbon/chemistry , Carbon/metabolism , Oxidation-Reduction
12.
Drug Metab Dispos ; 52(7): 673-680, 2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38658163

ABSTRACT

Imaging mass spectrometry (IMS) is a powerful tool for mapping the spatial distribution of unlabeled drugs and metabolites that may find application in assessing drug delivery, explaining drug efficacy, and identifying potential toxicity. This study focuses on determining the spatial distribution of the antidepressant duloxetine, which is widely prescribed despite common adverse effects (liver injury, constant headaches) whose mechanisms are not fully understood. We used high-resolution IMS with matrix-assisted laser desorption/ionization to examine the distribution of duloxetine and its major metabolites in four mouse organs where it may contribute to efficacy or toxicity: brain, liver, kidney, and spleen. In none of these tissues is duloxetine or its metabolites homogeneously distributed, which has implications for both efficacy and toxicity. We found duloxetine to be similarly distributed in spleen red pulp and white pulp but differentially distributed in different anatomic regions of the liver, kidney, and brain, with dose-dependent patterns. Comparison with hematoxylin and eosin staining of tissue sections reveals that the ion images of endogenous lipids help delineate anatomic regions in the brain and kidney, while heme ion images assist in differentiating regions within the spleen. These endogenous metabolites may serve as a valuable resource for examining the spatial distribution of other drugs in tissues when staining images are not available. These findings may facilitate future mechanistic studies of the therapeutic and adverse effects of duloxetine. In the current work, we did not perform absolute quantification of duloxetine, which will be reported in due course. SIGNIFICANCE STATEMENT: The study utilized imaging mass spectrometry to examine the spatial distribution of duloxetine and its primary metabolites in mouse brain, liver, kidney, and spleen. These results may pave the way for future investigations into the mechanisms behind duloxetine's therapeutic and adverse effects. Furthermore, the mass spectrometry images of specific endogenous metabolites such as heme could be valuable in analyzing the spatial distribution of other drugs within tissues in scenarios where histological staining images are unavailable.


Subject(s)
Antidepressive Agents , Brain , Duloxetine Hydrochloride , Kidney , Liver , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Spleen , Animals , Duloxetine Hydrochloride/metabolism , Mice , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Spleen/metabolism , Spleen/drug effects , Brain/metabolism , Brain/drug effects , Brain/diagnostic imaging , Kidney/metabolism , Kidney/drug effects , Liver/metabolism , Liver/drug effects , Antidepressive Agents/metabolism , Tissue Distribution , Male , Mice, Inbred C57BL
13.
Sci Total Environ ; 927: 172143, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38569967

ABSTRACT

Atmospheric organic peroxides (POs) play a key role in the formation of O3 and secondary organic aerosol (SOA), impacting both air quality and human health. However, there still remain technical challenges in investigating the reactivity of POs in ambient aerosols due to the instability and lack of standards for POs, impeding accurate evaluation of their environmental impacts. In the present study, we conducted the first attempt to categorize and quantify POs in ambient PM2.5 through hydrolysis, which is an important transformation pathway for POs, thus revealing the reactivities of various POs. POs were generally categorized into hydrolyzable POs (HPO) and unhydrolyzable POs (UPO). HPO were further categorized into three groups: short-lifetime HPO (S-HPO), intermediate-lifetime HPO (I-HPO), and long-lifetime HPO (L-HPO). S-HPO and L-HPO are typically formed from Criegee intermediate (CI) and RO2 radical reactions, respectively. Results show that L-HPO are the most abundant HPO, indicating the dominant role of RO2 pathway in HPO formation. Despite their lower concentration compared to L-HPO, S-HPO make a major contribution to the HPO hydrolysis rate due to their faster rate constants. The hydrolysis of PM2.5 POs accounts for 19 % of the nighttime gas-phase H2O2 growth during the summer observation, constituting a noteworthy source of gas-phase H2O2 and contributing to the atmospheric oxidation capacity. Seasonal and weather conditions significantly impact the composition of POs, with HPO concentrations in summer being significantly higher than those in winter and elevated under rainy and nighttime conditions. POs are mainly composed of HPO in summer, while in winter, POs are dominated by UPO.

14.
ACS Omega ; 9(12): 13897-13905, 2024 Mar 26.
Article in English | MEDLINE | ID: mdl-38559937

ABSTRACT

Shock-absorbing materials play a vital role in various industrial sectors, including construction and transportation. Among these materials, natural rubber (NR) stands out due to its exceptional elastic and mechanical properties, coupled with its robust crack resistance. Nevertheless, with the rising demand for enhanced damping capacities, there is a need to further optimize the damping performance of NR. One direct approach is to blend it with high-damping rubber. Butyl rubber (IIR) is a prominent member of the high-damping rubber category. Integrating IIR effectively with the NR, however, presents challenges. These challenges arise from IIR's inherent characteristics, such as its low unsaturation, slower vulcanization rate, and restricted compatibility with NR. Addressing these challenges, our study employed isoprene and isobutene to synthesize a variant of butyl rubber with a higher degree of unsaturation-achieving an unsaturation level between 4 and 6 mol %. Notably, this heightened unsaturation significantly expedited the curing time of IIR and facilitated the concurrent vulcanization of both IIR and NR. Utilizing atomic force microscopy, we observed that the introduction of unsaturated double bonds ameliorated the compatibility between NR and IIR, leading to an interfacial region extending up to 1000 nm. Our tests using a dynamic mechanical analyzer and rubber processing analyzer demonstrated the material's damping temperature range. Furthermore, there was a noticeable rise in the loss factor (tan δ) at ambient temperature, which remains over 0.1 across both a frequency window of 0.2 to 5 Hz and a strain spectrum of 10 to 200%. This tan δ enhancement ensured the potential of these rubber composites for shock-absorbing applications.

15.
Adv Healthc Mater ; 13(16): e2303474, 2024 06.
Article in English | MEDLINE | ID: mdl-38458151

ABSTRACT

Electrotherapy is of great interest in the field of tissue repair as an effective, well-tolerated, and noninvasive treatment. Triboelectric nanogenerator (TENG) has shown advantages in promoting wound healing due to its peak output characteristic and low Joule heating effect. However, it is limited in infected wound healing due to poor antimicrobial capacity. Here, a wearable triboelectric stimulator (WTS) is developed that consists of a flexible TENG (F-TENG) and a triboelectric-responsive drug delivery hydrogel (TR-DDH) for healing of bacterium-infected wounds. F-TENG can generate pulsed current to wounds by converting mechanical energy from body movements. Polypyrrole is prone to reduction and volume contraction under electrical stimulation, resulting in desorption of curcumin nanoparticles (CUR NPs) from the polypyrrole in TR-DDH. Therefore, the highly efficient and controllable release of CUR NPs can be achieved by triboelectric stimulation. According to the in vitro and in vivo experiments, WTS has the greatest antimicrobial effect and the fastest promotion of infected wound healing compared to treatment with electrical stimulation or curcumin. Finally, the safety assessment demonstrates that the WTS has excellent tissue safety for chronic wound healing. Synergistic therapy with WTS provides an efficient strategy for chronic wound healing and smart-responsive drug delivery systems.


Subject(s)
Curcumin , Drug Delivery Systems , Hydrogels , Pyrroles , Wound Healing , Wound Healing/drug effects , Curcumin/chemistry , Curcumin/pharmacology , Hydrogels/chemistry , Animals , Drug Delivery Systems/methods , Pyrroles/chemistry , Polymers/chemistry , Nanoparticles/chemistry , Mice , Electric Stimulation Therapy/methods , Wearable Electronic Devices , Humans , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Male
16.
ACS Macro Lett ; 13(4): 415-422, 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-38526986

ABSTRACT

Linear polyisoprene (PI) and SiO2-g-PI particle brushes were synthesized by both conventional and activators regenerated by electron transfer (ARGET) atom transfer radical polymerization (ATRP). The morphology and solution state study on the particle brushes by transmission electron microscopy (TEM) and dynamic light scattering (DLS) confirmed the successful grafting of PI ligands on the silica surface. The presence of nanoparticle clusters suggests low grafting density (associated with the limited initiation efficiency of ARGET for PI). Nevertheless, particle brushes with very high molecular weights, Mn > 300,000, were prepared, which significantly improved the dispersion of silica nanoparticles and also contributed to excellent mechanical performance. The reinforcing effects of SiO2 nanofillers and very high molecular weight PI ligands were investigated by dynamic mechanical analysis (DMA) as well as computational simulation for the cured linear PI homopolymer/SiO2-g-PI particle brush bulk films.

17.
J Control Release ; 368: 623-636, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38479445

ABSTRACT

Chemoresistance to cisplatin remains a significant challenge affecting the prognosis of advanced oral squamous cell carcinoma (OSCC). However, the specific biomarkers and underlying mechanisms responsible for cisplatin resistance remain elusive. Through comprehensive bioinformatic analyses, we identified a potential biomarker, BCL2 associated athanogene-1 (BAG1), showing elevated expression in head and neck squamous cell carcinoma (HNSCC). Since OSCC represents the primary pathological type of HNSCC, we investigated BAG1 expression in human tumor tissues and cisplatin resistant OSCC cell lines, revealing that silencing BAG1 induced apoptosis in cisplatin-resistant cells both in vitro and in vivo. This effect led to impaired cell viability of cisplatin resistant OSCC cells and indicated a positive correlation between BAG1 expression and the G1/S transition during cell proliferation. Based on these insights, the administration of a CDK4/6 inhibitor in combination with cisplatin effectively overcame cisplatin resistance in OSCC through the CDK4/6-BAG1 axis. Additionally, to enable simultaneous drug delivery and enhance synergistic antitumor efficacy, we developed a novel supramolecular nanodrug LEE011-FFERGD/CDDP, which was validated in an OSCC orthotopic mouse model. In summary, our study highlights the potential of a combined administration of CDK4/6 inhibitor and cisplatin as a promising therapeutic regimen for treating advanced or cisplatin resistant OSCC.


Subject(s)
Carcinoma, Squamous Cell , Cyclin-Dependent Kinase 4 , Cyclin-Dependent Kinase 6 , Drug Resistance, Neoplasm , Mouth Neoplasms , Nanoparticles , Animals , Humans , Mice , Carcinoma, Squamous Cell/drug therapy , Carcinoma, Squamous Cell/metabolism , Carcinoma, Squamous Cell/pathology , Cell Line, Tumor , Cell Proliferation , Cisplatin/pharmacology , Cisplatin/therapeutic use , Cyclin-Dependent Kinase 4/antagonists & inhibitors , Head and Neck Neoplasms/drug therapy , Mouth Neoplasms/drug therapy , Mouth Neoplasms/metabolism , Mouth Neoplasms/pathology , Squamous Cell Carcinoma of Head and Neck/drug therapy , Cyclin-Dependent Kinase 6/antagonists & inhibitors
18.
J Am Chem Soc ; 146(9): 5940-5951, 2024 Mar 06.
Article in English | MEDLINE | ID: mdl-38386410

ABSTRACT

Solid polymer electrolytes (SPEs) are one of the most practical candidates for solid-state batteries owing to their high flexibility and low production cost, but their application is limited by low Li+ conductivity and a narrow electrochemical window. To improve performance, it is necessary to reveal the structure-property relationship of SPEs. Here, 23 fluorinated linear polyesters were prepared by editing the coordination units, flexible linkage segments, and interface passivating groups. Besides the traditionally demonstrated coordinating capability and flexibility of polymer chains, the molecular asymmetry and resulting interchain aggregation are observed critical for Li+ conductivity. By tailoring the molecular asymmetry and coordination ability of polyesters, the Li+ conductivity can be raised by 10 times. Among these polyesters, solvent-free poly(pentanediol adipate) delivers the highest room-temperature Li+ conductivity of 0.59 × 10-4 S cm-1. The chelating coordination of oxalate and Li+ leads to an electron delocalization of alkoxy oxygen, enhancing the antioxidation capability of SPEs. To lower the cost, high-value LiTFSI in SPEs is recycled at 90%, and polyesters can be regenerated at 86%. This work elucidates the structure-property relationship of polyester-based SPEs, displays the design principles of SPEs, and provides a way for the development of sustainable solid-state batteries.

19.
Regen Biomater ; 11: rbad102, 2024.
Article in English | MEDLINE | ID: mdl-38173777

ABSTRACT

The removal of a failed implant with high torque causes significant damage to the surrounding tissue, compromising bone regeneration and subsequent osseointegration in the defect area. Here, we report a case of carrier screw fracture followed by immediate implant removal, bone grafting and delayed reimplantation. A dental implant with a fractured central carrier screw was removed using the bur-forceps technique. The resulting three-wall bone defect was filled with granular surface demineralized freeze-dried bone allograft (SD-FDBA). Cone-beam computerized tomography was performed at 1 week, 6 months and 15 months postoperatively and standardized for quantitative evaluation. The alveolar bone width and height at 15 months post-surgery were about 91% of the original values, with a slightly lower bone density, calculated using the gray value ratio. The graft site was reopened and was found to be completely healed with dense and vascularized bone along with some residual bone graft. Reimplantation followed by restoration was performed 8 months later. The quality of regenerated bone following SD-FDBA grafting was adequate for osseointegration and long-term implant success. The excellent osteogenic properties of SD-FDBA are attributed to its human origin, cortical bone-like structure, partly demineralized surfaces and bone morphogenetic protein-2-containing nature. Further investigation with more cases and longer follow-up was required to confirm the final clinical effect.

20.
Ann Clin Lab Sci ; 53(6): 931-937, 2024 Jan 04.
Article in English | MEDLINE | ID: mdl-38182144

ABSTRACT

OBJECTIVE: The world has been faced with the repeat rise of SARS-CoV-2 variants since late 2020, including Alpha, Beta, Gamma, Delta, and the latest simultaneous emergence of far-flung spawn of Omicron sub-lineages in different parts of the globe. This has brought us the challenge of determining what factor(s) have been the selective force behind these immune evasive and therapy resistant mutations. It is very possible that such variants evolved in limited host individuals with prolonged infections, or from a localized community of patients. METHODS: This study surveys the GISAID time capsule of mutations found in viral genomes from patients with prolonged same lineage viral infections. We analyzed 288 SARS-CoV-2 genomes representing 113 patients who had same lineage viral genomes in two or more samples stored in GISAID. RESULTS: Of these, thirty-five (30.9%) of the 113 patients developed mutations during their infections. Samples from patients whose viral genomes showed nucleotide changes(s) (n=35) versus those that showed no change (n=78) had a statistically significant difference (p=2.121x10-4) in duration of infection by a median of 13 days (range 0-109 days) versus 6 days (range 0-72 days), respectively. Five highly recognizable variant-defining mutations with immune evasion properties were identified in 5 cases infected by the B.1 lineages in late 2020 and early 2021. CONCLUSION: This suggests the duration of infection is a contributing factor that gives rise to mutations, but not the sole factor, and individual host conditions may play a critical role in driving viral evolution.


Subject(s)
COVID-19 , Humans , COVID-19/genetics , SARS-CoV-2/genetics , Mutation/genetics , Biotin
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