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1.
Int J Biol Macromol ; 279(Pt 3): 135271, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39233170

RESUMEN

Due to the heterogeneity of the tumor microenvironment, the clinical efficacy of tumor treatment is not satisfied, highlighting the necessity for new strategies to tackle this issue. To effectively treat breast tumors by tumor-targeted chemo/chemodynamic therapy, herein, the Fe3+-rich MIL-88B nanobullets (MNs) covered with hyaluronic acid (HA) were fabricated as vehicles of zoledronic acid (ZA). The attained ZA@HMNs showed a high ZA payload (ca 29.6 %), outstanding colloidal stability in the serum-containing milieu, and accelerated ZA as well as Fe3+ release under weakly acidic and glutathione (GSH)-rich conditions. Also, the ZA@HMNs consumed GSH by GSH-mediated Fe3+ reduction and converted H2O2 into OH via Fenton or Fenton-like reaction with pH reduction. After being internalized by 4T1 cells upon CD44-mediated endocytosis, the ZA@HMNs depleted intracellular GSH and degraded H2O2 into OH, thus eliciting lipid peroxidation and mitochondria damage to suppress cell proliferation. Also, the ZA@HMNs remarkably killed macrophage-like RAW 264.7 cells. Importantly, the in vivo studies and ki67 and GPX4 staining of tumor sections demonstrated that the ZA@HMNs efficiently accumulated in 4T1 tumors to hinder tumor growth via ZA chemotherapy combined with OH-mediated ferroptosis. This work presents a practicable strategy to fabricate ZA@HMNs for breast tumor-targeted chemo/chemodynamic therapy with potential clinical translation.

2.
Cureus ; 16(8): e66882, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39280556

RESUMEN

Introduction Proximity of organs at risk (OAR) hinders radiation dose escalation for the treatment of pancreatic cancer. To address this limitation, there is interest in protracted-fractionation (PF: 15 to 25 fractions) courses employing moderate hypofractionation (MHF: 3-4 Gy/fraction). However, there persists underdosing where tumor interfaces with OAR. The significance of compromised tumor coverage and dose heterogeneity on tumor control remains unknown. Here, we report our initial planning experience with PF-MHF in pancreatic cancer. Methods We retrospectively reviewed radiation courses for locally advanced or recurrent pancreatic cancer with a PF-MHF approach: 45 Gy in 25 fractions (1.8 Gy/fraction) to PTV with 75 Gy (3 Gy/fraction) as an integrated boost to the GTV. We reviewed dosimetric parameters for the GTV: percentage overlap with planning OAR volume (PRV-GTV overlap), D99.9%, D0.1cc, Dmean, V75Gy, and V60Gy. We also calculated the GTV's generalized equivalent uniform dose (gEUD) value using two different a values (-5 and -15). Lastly, we reoptimized two plans with two approaches: increasing gEUD or relaxing the maximum dose constraint. Results A total of 26 plans were included in our analysis: 14 locally advanced and 12 locally recurrent pancreatic cancer cases. While the D0.1cc median value was 81.7 Gy, target volume coverage was relatively low (V75Gy median 71%). Median gEUD were 71 Gy (a = -5) and 62.8 Gy (a = -15) and inversely correlated with PRV-GTV overlap. On reoptimized plans, both approaches yielded similar results, but an increase in target coverage and gEUD were seen only when there was limited PRV-GTV overlap. Conclusion Although radiation dose can be escalated within the GTV, there continues to be low coverage by the prescription dose, especially with high PRV-GTV overlap. Relaxing the maximum dose constraint in planning allows for meaningful improvement in tumor coverage in limited PRV overlap scenarios. Continued refinement of the PF-MHF approach is needed.

3.
Support Care Cancer ; 32(9): 624, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39222130

RESUMEN

PURPOSE: The Palliative Care Outcomes Collaboration (PCOC) aims to enhance patient outcomes systematically. However, identifying crucial items and accurately determining PCOC phases remain challenging. This study aims to identify essential PCOC data items and construct a prediction model to accurately classify PCOC phases in terminal patients. METHODS: A retrospective cohort study assessed PCOC data items across four PCOC phases: stable, unstable, deteriorating, and terminal. From July 2020 to March 2023, terminal patients were enrolled. A multinomial mixed-effect regression model was used for the analysis of multivariate PCOC repeated measurement data. RESULTS: The dataset comprised 1933 terminally ill patients from 4 different hospice service settings. A total of 13,219 phases of care were analyzed. There were significant differences in the symptom assessment scale, palliative care problem severity score, Australia-modified Karnofsky performance status, and resource utilization groups-activities of daily living among the four PCOC phases of care. Clinical needs, including pain and other symptoms, declined from unstable to terminal phases, while psychological/spiritual and functional status for bed mobility, eating, and transfers increased. A robust prediction model achieved areas under the curves (AUCs) of 0.94, 0.94, 0.920, and 0.96 for stable, unstable, deteriorating, and terminal phases, respectively. CONCLUSIONS: Critical PCOC items distinguishing between PCOC phases were identified, enabling the development of an accurate prediction model. This model enhances hospice care quality by facilitating timely interventions and adjustments based on patients' PCOC phases.


Asunto(s)
Cuidados Paliativos al Final de la Vida , Cuidados Paliativos , Humanos , Estudios Retrospectivos , Masculino , Femenino , Cuidados Paliativos al Final de la Vida/métodos , Anciano , Cuidados Paliativos/métodos , Persona de Mediana Edad , Anciano de 80 o más Años , Análisis de Regresión , Estudios de Cohortes , Adulto , Actividades Cotidianas , Estado de Ejecución de Karnofsky
4.
Sci Rep ; 14(1): 20579, 2024 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-39242614

RESUMEN

During COVID-19 pandemic, cases of postvaccination infections and restored SARS-CoV-2 virus have increased after full vaccination, which might be contributed to by immune surveillance escape or virus rebound. Here, artificial linear 9-mer human leucocyte antigen (HLA)-restricted UC peptides were designed based on the well-conserved S2 region of the SARS-CoV-2 spike protein regardless of rapid mutation and glycosylation hindrance. The UC peptides were characterized for its effect on immune molecules and cells by HLA-tetramer refolding assay for HLA-binding ability, by HLA-tetramer specific T cell assay for engaged cytotoxic T lymphocytes (CTLs) involvement, by HLA-dextramer T cell assay for B cell activation, by intracellular cytokine release assay for polarization of immune response, Th1 or Th2. The specific lysis activity assay of T cells was performed for direct activation of cytotoxic T lymphocytes by UC peptides. Mice were immunized for immunogenicity of UC peptides in vivo and immunized sera was assay for complement cytotoxicity assay. Results appeared that through the engagement of UC peptides and immune molecules, HLA-I and II, that CTLs elicited cytotoxic activity by recognizing SARS-CoV-2 spike-bearing cells and preferably secreting Th1 cytokines. The UC peptides also showed immunogenicity and generated a specific antibody in mice by both intramuscular injection and oral delivery without adjuvant formulation. In conclusion, a T-cell vaccine could provide long-lasting protection against SARS-CoV-2 either during reinfection or during SARS-CoV-2 rebound. Due to its ability to eradicate SARS-CoV-2 virus-infected cells, a COVID-19 T-cell vaccine might provide a solution to lower COVID-19 severity and long COVID-19.


Asunto(s)
Linfocitos B , Vacunas contra la COVID-19 , COVID-19 , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , Linfocitos T Citotóxicos , Vacunas de Subunidad , Glicoproteína de la Espiga del Coronavirus/inmunología , Animales , Humanos , Ratones , SARS-CoV-2/inmunología , Vacunas contra la COVID-19/inmunología , Vacunas de Subunidad/inmunología , Vacunas de Subunidad/administración & dosificación , Linfocitos B/inmunología , Linfocitos T Citotóxicos/inmunología , COVID-19/inmunología , COVID-19/prevención & control , Femenino , Antígenos HLA/inmunología , Ratones Endogámicos BALB C , Vacunas de Subunidades Proteicas
5.
J Colloid Interface Sci ; 677(Pt A): 400-415, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39096708

RESUMEN

Chemodynamic therapy (CDT), an emerging cancer treatment modality, uses multivalent metal elements to convert endogenous hydrogen peroxide (H2O2) to toxic hydroxyl radicals (•OH) via a Fenton or Fenton-like reaction, thus eliciting oxidative damage of cancer cells. However, the antitumor potency of CDT is largely limited by the high glutathione (GSH) concentration and low catalytic efficiency in the tumor sites. The combination of CDT with chemotherapy provides a promising strategy to overcome these limitations. In this work, to enhance antitumor potency by tumor-targeted and GSH depletion-amplified chemodynamic-chemo therapy, the hyaluronic acid (HA)/polydopamine (PDA)-decorated Fe2+-doped ZIF-8 nano-scaled metal-organic frameworks (FZ NMs) were fabricated and utilized to load doxorubicin (DOX), a chemotherapy drug, via hydrophobic, π-π stacking and charge interactions. The attained HA/PDA-covered DOX-carrying FZ NMs (HPDFZ NMs) promoted DOX and Fe2+ release in weakly acidic and GSH-rich milieu and exhibited acidity-activated •OH generation. Through efficient CD44-mediated endocytosis, the HPDFZ NMs internalized by CT26 cells not only prominently enhanced •OH accumulation by consuming GSH via PDA-mediated Michael addition combined with Fe2+/Fe3+ redox couple to cause mitochondria damage and lipid peroxidation, but also achieved intracellular DOX release, thus eliciting apoptosis and ferroptosis. Importantly, the HPDFZ NMs potently inhibited CT26 tumor growth in vivo at a low DOX dose and had good biosafety, thereby showing promising potential in tumor-specific treatment.

6.
Artículo en Inglés | MEDLINE | ID: mdl-39147627

RESUMEN

OBJECTIVES: To understand the microbial profile and investigate the independent predictors for healthcare-associated pneumonia (HCAP) pertinaciously caused by isolates of multidrug-resistant (MDR) Gram-negative bacteria (GNB). METHODS: Multicenter ICU patients who received appropriate antibiotic treatments for preceding pneumonia due to MDR GNB isolates and subsequently developed HCAP caused by either MDR GNB (n = 126) or non-MDR GNB (n = 40) isolates in Taiwan between 2018 and 2023 were enrolled. Between the groups of patients with HCAP due to MDR GNB and non-MDR GNB, the proportions of the following variables, including demographic characteristics, important co-morbidities, nursing home residence, physiological severity, intervals between two hospitalizations, steroid use, the tracheostomy tube use alone, ventilator support, and the predominant GNB species involving HCAP, were analyzed using the chi-square test. Logistic regression was employed to explore the independent predictors for HCAP persistently caused by MDR GNB in the aforementioned variables with a P-value of <0.15 in the univariate analysis. RESULTS: MDR-Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii complex were the three predominant species causing HCAP. Chronic structural lung disorders, diabetes mellitus, intervals of ≤30 days between two hospitalizations, use of the tracheostomy tube alone, and prior pneumonia caused by MDR A. baumannii complex were shown to independently predict the HCAP tenaciously caused by MDR GNB. Conversely, the preceding pneumonia caused by MDR P. aeruginosa was a negative predictor. CONCLUSION: Identifying predictors for HCAP persistently caused by MDR GNB is crucial for prescribing appropriate antibiotics.

7.
Arch Med Sci ; 20(2): 632-640, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38757031

RESUMEN

Introduction: Impairments in wound healing commonly occur among patients with diabetes. Herbal medicines have a long history of usage in wound care management. Super green (SG) is a newly discovered natural product obtained from Musa paradisiaca. This study aimed to investigate the efficacy of the topical application of SG in healing surgical wounds in diabetic rats. Material and methods: Wistar rats received a one-time intraperitoneal injection of streptozotocin to induce type 1 diabetes. Full-thickness excisional skin wounds were created on the backs of the rats. The relevant groups were topically treated with the indicated concentrations of SG or vehicle dressing throughout the study duration. Histological analysis was performed and the mRNA levels of proinflammatory cytokines were measured to evaluate the improvement of wound closure. Results: The wound area ratio of the SG (1/6000 dilution)-treated group was greatly reduced compared to that of the vehicle-treated group. The histological analysis showed fewer inflammatory cells, accelerated re-epithelialization, and increased collagen deposition in SG 1/6000-treated wounds. The gene expression levels of tumor necrosis factor-α, interleukin-1ß, and interleukin-6 were decreased and the levels of type I and type III collagen were increased after SG treatment. Conclusions: These results show that the most therapeutically efficacious concentration of SG (1/6000 dilution) can enhance wound repair in diabetic rats. SG has the potential to be a new treatment strategy for diabetic wounds.

8.
Front Pharmacol ; 15: 1361501, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38698820

RESUMEN

Background: Bismuth subsalicylate (BSS), probiotics, rifaximin, and vaccines have been proposed as preventive modalities for patients with travelers' diarrhea (TD), but their comparative effectiveness for prevention has rarely been studied. We aimed to perform a systematic review and network meta-analysis to test whether one of these modalities is more effective than the others in reducing the incidence of TD. Methods: We searched Pubmed, Embase, the Cochrane Central Register of Controlled Trials (CENTRAL), Web of Science, and clinical registries from inception of the databases through 18 November 2023, without language restriction, for randomized controlled trials (RCTs) evaluating the efficacy of BSS, probiotics, rifaximin, and vaccines in preventing TD. The primary outcome was the incidence of TD and the safety outcome was the incidence of adverse events. The relative ratio (RR) was used to assess the effect of the modalities, and RR estimates between any two of the modalities were calculated and pooled using a frequentist network meta-analysis model. Results: Thirty-one studies (recruiting 10,879 participants) were included in the analysis. Sixteen were judged to have a low risk of bias. In the aggregate analysis, BSS and rifaximin were more effective than placebo and other treatment modalities, which was further confirmed in the individual analysis. The comparison between rifaximin and placebo achieved high confidence, while the comparisons between BSS and placebo, ETEC and probiotics, and rifaximin and vaccines achieved moderate confidence. BSS had a higher rate of adverse events compared with other treatments. Conclusion: Rifaximin had a relative lower TD incidence and lower adverse event rate, and the evidence was with moderate confidence. Systematic Review Registration: https://osf.io/dxab6, identifier.

9.
Front Psychiatry ; 15: 1384176, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38812491

RESUMEN

Alzheimer's disease psychosis (ADP) produces a significant burden for patients and their care partners, but at present there are no approved treatments for ADP. The lack of approved treatments may be due to the challenges of conducting clinical trials for this disease. This perspective article discusses distinct challenges and proposed solutions of conducting ADP trials involving seven key areas: (1) methods to reduce the variable and sometimes high rates of placebo response that occur for treatments of neuropsychiatric symptoms; (2) the use of combined or updated criteria that provide a precise, consensus definition of ADP; (3) the use of eligibility criteria to help recruit individuals representative of the larger ADP population and overcome the difficulty of recruiting patients with moderate-to-severe ADP; (4) consideration of multiple perspectives and implementation of technology to reduce the variability in the administration and scoring of neuropsychiatric symptom assessments; (5) the use of clinically appropriate, a priori-defined severity thresholds and responder cutoffs; (6) the use of statistical approaches that address absolute effect sizes and a three-tier approach to address the fluctuation of neuropsychiatric symptoms; and (7) the implementation of feasible diagnostic and target-engagement biomarkers as they become available. The goal of these proposed solutions is to improve the evaluation of potential ADP therapies, within the context of randomized, placebo-controlled trials with clinically meaningful endpoints and sustained treatment responses.

10.
Biomed Pharmacother ; 174: 116572, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38626519

RESUMEN

Epigenetic regulation and mitochondrial dysfunction are essential to the progression of idiopathic pulmonary fibrosis (IPF). Curcumin (CCM) in inhibits the progression of pulmonary fibrosis by regulating the expression of specific miRNAs and pulmonary fibroblast mitochondrial function; however, the underlying mechanism is unclear. C57BL/6 mice were intratracheally injected with bleomycin (5 mg/kg) and treated with CCM (25 mg/kg body weight/3 times per week, intraperitoneal injection) for 28 days. Verhoeff-Van Gieson, Picro sirius red, and Masson's trichrome staining were used to examine the expression and distribution of collagen and elastic fibers in the lung tissue. Pulmonary fibrosis was determined using micro-computed tomography and transmission electron microscopy. Human pulmonary fibroblasts were transfected with miR-29a-3p, and RT-qPCR, immunostaining, and western blotting were performed to determine the expression of DNMT3A and extracellular matrix collagen-1 (COL1A1) and fibronectin-1 (FN1) levels. The expression of mitochondrial electron transport chain complex (MRC) and mitochondrial function were detected using western blotting and Seahorse XFp Technology. CCM in increased the expression of miR-29a-3p in the lung tissue and inhibited the DNMT3A to reduce the COL1A1 and FN1 levels leading to pulmonary extracellular matrix remodeling. In addition, CCM inhibited pulmonary fibroblasts MRC and mitochondrial function via the miR-29a-3p/DNMT3A pathway. CCM attenuates pulmonary fibrosis via the miR-29a-3p/DNMT3A axis to regulate extracellular matrix remodeling and mitochondrial function and may provide a new therapeutic intervention for preventing pulmonary fibrosis.


Asunto(s)
Curcumina , ADN Metiltransferasa 3A , Matriz Extracelular , Fibroblastos , Ratones Endogámicos C57BL , MicroARNs , Mitocondrias , Animales , MicroARNs/genética , MicroARNs/metabolismo , Curcumina/farmacología , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , ADN Metiltransferasa 3A/metabolismo , Matriz Extracelular/metabolismo , Matriz Extracelular/efectos de los fármacos , Humanos , Ratones , Masculino , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Fibroblastos/patología , Bleomicina , Fibrosis Pulmonar/genética , Fibrosis Pulmonar/patología , Fibrosis Pulmonar/metabolismo , Fibrosis Pulmonar/tratamiento farmacológico , Pulmón/efectos de los fármacos , Pulmón/patología , Pulmón/metabolismo , ADN (Citosina-5-)-Metiltransferasas/metabolismo , ADN (Citosina-5-)-Metiltransferasas/genética , Fibrosis Pulmonar Idiopática/patología , Fibrosis Pulmonar Idiopática/genética , Fibrosis Pulmonar Idiopática/tratamiento farmacológico , Fibrosis Pulmonar Idiopática/metabolismo , Modelos Animales de Enfermedad
11.
Int J Biol Macromol ; 266(Pt 2): 131359, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38580018

RESUMEN

The combination of photothermal therapy (PTT) and photodynamic therapy (PDT) has emerged as a promising strategy for cancer treatment. However, the poor photostability and photothermal conversion efficiency (PCE) of organic small-molecule photosensitizers, and the intracellular glutathione (GSH)-mediated singlet oxygen scavenging largely decline the antitumor efficacy of PTT and PDT. Herein, a versatile nanophotosensitizer (NPS) system is developed by ingenious incorporation of indocyanine green (ICG) into the PEGylated chitosan (PEG-CS)-coated polydopamine (PDA) nanoparticles via multiple π-π stacking, hydrophobic and electrostatic interactions. The PEG-CS-covered NPS showed prominent colloidal and photothermal stability as well as high PCE (ca 62.8 %). Meanwhile, the Michael addition between NPS and GSH can consume GSH, thus reducing the GSH-induced singlet oxygen scavenging. After being internalized by CT26 cells, the NPS under near-infrared laser irradiation produced massive singlet oxygen with the aid of thermo-enhanced intracellular GSH depletion to elicit mitochondrial damage and lipid peroxide formation, thus leading to ferroptosis and apoptosis. Importantly, the combined PTT and PDT delivered by NPS effectively inhibited CT26 tumor growth in vivo by light-activated intense hyperthermia and redox homeostasis disturbance. Overall, this work presents a new tactic of boosting antitumor potency of ICG-mediated phototherapy by PEG-CS-covered NPS.


Asunto(s)
Quitosano , Glutatión , Nanopartículas , Fotoquimioterapia , Fármacos Fotosensibilizantes , Terapia Fototérmica , Polietilenglicoles , Quitosano/química , Fotoquimioterapia/métodos , Animales , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacología , Glutatión/metabolismo , Polietilenglicoles/química , Ratones , Nanopartículas/química , Terapia Fototérmica/métodos , Línea Celular Tumoral , Verde de Indocianina/química , Neoplasias/terapia , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Oxígeno Singlete/metabolismo , Humanos , Apoptosis/efectos de los fármacos , Indoles/química , Indoles/farmacología , Polímeros/química
12.
Heliyon ; 10(7): e28755, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38586372

RESUMEN

Fish mint, Houttuynia cordata Thunb. (HCT) is an edible vegetable that has also been used in traditional folk medicines. As both a medicinal herb and a dietary source, HCT has been clinically proven to be a pivotal ingredient in formulas administered to alleviate COVID-19 symptoms. With the increasing market demand for imported materials, ensuring the quality consistency of HCT becomes a significant concern. In this study, the growing time for hydroponically-cultivated HCT with seaweed extract and amino acids added (HCTW) reduced by half compared to conventional soil-cultivated HCT (HCTS). Key quantified components in HCTW, flavonoid glycosides and caffeoylquinic acid derivatives, exhibited a 143% increase over HCTS. These crucial constituents were responsible for possessing antioxidant activity (IC50 < 25 µg/mL) and anti-nitrite oxide production (IC50 < 20 µg/mL). An economically-designed hydroponic system with appropriate additives is proposed to replace HCTS with improvements of growth time, overall production yields, and bioactive qualities.

13.
JBMR Plus ; 8(5): ziae039, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38644977

RESUMEN

The Fracture Risk Assessment Tool (FRAX®) is a widely utilized country-specific calculator for identifying individuals with high fracture risk; its score is calculated from 12 variables, but its formulation is not publicly disclosed. We aimed to decompose and simplify the FRAX® by utilizing a nationwide community survey database as a reference module for creating a local assessment tool for osteoporotic fracture community screening in any country. Participants (n = 16384; predominantly women (75%); mean age = 64.8 years) were enrolled from the Taiwan OsteoPorosis Survey, a nationwide cross-sectional community survey collected from 2008 to 2011. We identified 11 clinical risk factors from the health questionnaires. BMD was assessed via dual-energy X-ray absorptiometry in a mobile DXA vehicle, and 10-year fracture risk scores, including major osteoporotic fracture (MOF) and hip fracture (HF) risk scores, were calculated using the FRAX®. The mean femoral neck BMD was 0.7 ± 0.1 g/cm2, the T-score was -1.9 ± 1.2, the MOF was 8.9 ± 7.1%, and the HF was 3.2 ± 4.7%. Following FRAX® decomposition with multiple linear regression, the adjusted R2 values were 0.9206 for MOF and 0.9376 for HF when BMD was included and 0.9538 for MOF and 0.9554 for HF when BMD was excluded. The FRAX® demonstrated better prediction for women and younger individuals than for men and elderly individuals after sex and age stratification analysis. Excluding femoral neck BMD, age, sex, and previous fractures emerged as 3 primary clinical risk factors for simplified FRAX® according to the decision tree analysis in this study population. The adjusted R2 values for the simplified country-specific FRAX® incorporating 3 premier clinical risk factors were 0.8210 for MOF and 0.8528 for HF. After decomposition, the newly simplified module provides a straightforward formulation for estimating 10-year fracture risk, even without femoral neck BMD, making it suitable for community or clinical osteoporotic fracture risk screening.

14.
Nutrients ; 16(8)2024 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-38674927

RESUMEN

The excessive activation of glutamate in the brain is a factor in the development of vascular dementia. γ-Oryzanol is a natural compound that has been shown to enhance brain function, but more research is needed to determine its potential as a treatment for vascular dementia. This study investigated if γ-oryzanol can delay or improve glutamate neurotoxicity in an in vitro model of differentiated HT-22 cells and explored its neuroprotective mechanisms. The differentiated HT-22 cells were treated with 0.1 mmol/L glutamate for 24 h then given γ-oryzanol at appropriate concentrations or memantine (10 µmol/L) for another 24 h. Glutamate produced reactive oxygen species and depleted glutathione in the cells, which reduced their viability. Mitochondrial dysfunction was also observed, including the inhibition of mitochondrial respiratory chain complex I activity, the collapse of mitochondrial transmembrane potential, and the reduction of intracellular ATP levels in the HT-22 cells. Calcium influx triggered by glutamate subsequently activated type II calcium/calmodulin-dependent protein kinase (CaMKII) in the HT-22 cells. The activation of CaMKII-ASK1-JNK MAP kinase cascade, decreased Bcl-2/Bax ratio, and increased Apaf-1-dependent caspase-9 activation were also observed due to glutamate induction, which were associated with increased DNA fragmentation. These events were attenuated when the cells were treated with γ-oryzanol (0.4 mmol/L) or the N-methyl-D-aspartate receptor antagonist memantine. The results suggest that γ-oryzanol has potent neuroprotective properties against glutamate excitotoxicity in differentiated HT-22 cells. Therefore, γ-oryzanol could be a promising candidate for the development of therapies for glutamate excitotoxicity-associated neurodegenerative diseases, including vascular dementia.


Asunto(s)
Ácido Glutámico , Mitocondrias , Fármacos Neuroprotectores , Fenilpropionatos , Especies Reactivas de Oxígeno , Ácido Glutámico/toxicidad , Fenilpropionatos/farmacología , Animales , Fármacos Neuroprotectores/farmacología , Ratones , Línea Celular , Especies Reactivas de Oxígeno/metabolismo , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Oryza/química , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Memantina/farmacología , Apoptosis/efectos de los fármacos , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Neuronas/efectos de los fármacos , Neuronas/metabolismo
15.
Pharmaceuticals (Basel) ; 17(4)2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38675498

RESUMEN

The phenolic aldehyde syringaldehyde (SA) has been shown to have an antihyperglycemic effect in diabetic rats due to increased glucose utilization and insulin sensitivity. To understand the direct effect of SA on the GLP-1 receptor, STZ-induced diabetic rats were used. The levels of pro-inflammatory cytokines, liver enzymes, and renal function were measured using specific ELISA kits. The mechanisms of SA effects were investigated using CHO-K1 cells, pancreatic Min-6 cells, and cardiomyocyte H9c2 cells. The results indicated that the antihyperglycemic effect of SA in diabetic rats was abolished by blocking the GLP-1 receptor with an antagonist. SA has a direct effect on the GLP-1 receptor when using CHO-K1 cells transfected with the exogenous GLP-1 receptor gene. In addition, SA stimulated insulin production in Min-6 cells by activating GLP-1 receptors. SA caused a dose-dependent rise in GLP-1 receptor mRNA levels in cardiac H9c2 cells. These in vitro results support the notion that SA has a direct effect on the GLP-1 receptor. Otherwise, SA inhibited the increase of pro-inflammatory cytokines, including interleukins and tumor TNF-α, in type 1 diabetic rats in a dose-dependent manner. Moreover, as with liraglutide, SA reduced plasma lipid profiles, including total cholesterol and triglyceride, in mixed diet-induced type 2 diabetic rats. Intriguingly, chronic treatment with SA (as with liraglutide) reversed the functions of both the liver and the kidney in these diabetic rats. SA displayed less efficiency in reducing body weight and food consumption compared to liraglutide. In conclusion, SA effectively activates GLP-1 receptors, resulting in a reduction in diabetic-related complications in rats. Therefore, it is beneficial to develop SA as a chemical agonist for clinical applications in the future.

16.
17.
Angew Chem Int Ed Engl ; 63(20): e202401324, 2024 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-38499463

RESUMEN

We report the discovery and biosynthesis of new piperazine alkaloids-arizonamides, and their derived compounds-arizolidines, featuring heterobicyclic and spirocyclic isoquinolone skeletons, respectively. Their biosynthetic pathway involves two crucial non-heme iron enzymes, ParF and ParG, for core skeleton construction. ParF has a dual function facilitating 2,3-alkene formation of helvamide, as a substrate for ParG, and oxidative cleavage of piperazine. Notably, ParG exhibits catalytic versatility in multiple oxidative reactions, including cyclization and ring reconstruction. A key amino acid residue Phe67 was characterized to control the formation of the constrained arizonamide B backbone by ParG.


Asunto(s)
Alcaloides , Alcaloides/química , Alcaloides/metabolismo , Alcaloides/biosíntesis , Piperazinas/química , Piperazinas/metabolismo , Hierro/química , Hierro/metabolismo , Ciclización , Biocatálisis , Estructura Molecular , Compuestos de Espiro/química , Compuestos de Espiro/metabolismo , Oxidación-Reducción , Piperazina/química , Piperazina/metabolismo
18.
Surg Open Sci ; 18: 42-49, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38318322

RESUMEN

Background: Total neoadjuvant therapy (TNT) is an accepted approach for the management of locally advanced rectal cancer (LARC) and is associated with a decreased risk of development of metastatic disease compared to standard neoadjuvant therapy. However, questions remain regarding surgical outcomes and local control in patients who proceed to surgery, particularly when radiation is given first in the neoadjuvant sequence. We report on our institution's experience with patients who underwent short-course radiation therapy, consolidation chemotherapy, and surgery. Methods: We retrospectively reviewed surgical specimen outcomes, postoperative complications, and local/pelvic control in a large cohort of patients with LARC who underwent neoadjuvant therapy incorporating upfront short-course radiation therapy followed by consolidation chemotherapy. Results: In our cohort of 83 patients who proceeded to surgery, a complete/near-complete mesorectal specimen was achieved in 90 % of patients. This outcome was not associated with the time interval from completion of radiation to surgery. Postoperative complications were acceptably low. Local control at two years was 93.4 % for all patients- 97.6 % for those with low-risk disease and 90.4 % for high-risk disease. Conclusion: Upfront short-course radiation therapy and consolidation chemotherapy is an effective treatment course. Extended interval from completion of short-course radiation therapy did not impact surgical specimen quality.

19.
J Glob Antimicrob Resist ; 36: 411-418, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38331030

RESUMEN

OBJECTIVES: To evaluate the susceptibility of globally pneumonia-causing meropenem-resistant (MEM-R) Acinetobacter baumannii isolates against important antibiotics and estimate appropriate dosages of indicated antibiotics. METHODS: We extracted the 2014-2021 Antimicrobial Testing of Leadership Surveillance database regarding the susceptibility of MEM-R A. baumannii isolates causing pneumonia against important antibiotics. The susceptibility and carbapenemase-encoding gene (CPEG) data of pneumonia-causing MEM-R A. baumannii isolates from patients hospitalized in intensive care units of five major regions were analyzed. The susceptibility breakpoints (SBP) recommended by the Clinical and Laboratory Standards Institute (CLSI) in 2022, other necessary criteria [SBP of MIC for colistin, 2 mg/L, in the CLSI 2018; and cefoperazone-sulbactam (CFP-SUL), 16 mg/L], and the pharmacokinetic and pharmacodynamic data of indicated antibiotics were employed. RESULTS: Applying the aforementioned criteria, we observed the susceptible rates of colistin, minocycline, and CFP-SUL against the pneumonia-causing MEM-R A. baumannii isolates globally (n = 2905) were 93.2%, 69.1%, and 26.3%, respectively. Minocycline was significantly more active in vitro (MIC ≤4 mg/L) against the pneumonia-causing MEM-R A. baumannii isolates collected from North and South America compared to those from other regions (>90% vs. 58-72%). Additionally, blaOXA-23 and blaOXA-72 were the predominant CPEG in pneumonia-causing MEM-R A. baumannii isolates. CONCLUSIONS: After deliberative estimations, dosages of 200 mg minocycline intravenously every 12 h (SBP, 8 mg/L), 100 mg tigecycline intravenously every 12 h (SBP, 1 mg/L), and 160 mg nebulized colistin methanesulphonate every 8 h (SBP, 2 mg/L) are needed for the effective treatment of pneumonia-causing MEM-R A. baumannii isolates.


Asunto(s)
Infecciones por Acinetobacter , Acinetobacter baumannii , Antiinfecciosos , Neumonía , Humanos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Meropenem/farmacología , Meropenem/uso terapéutico , Minociclina/farmacología , Colistina/farmacología , Colistina/uso terapéutico , Liderazgo , Farmacorresistencia Bacteriana Múltiple , Infecciones por Acinetobacter/tratamiento farmacológico , Antiinfecciosos/farmacología , Neumonía/tratamiento farmacológico
20.
Patient Prefer Adherence ; 18: 207-216, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38264323

RESUMEN

Background: In patients with schizophrenia, study design to optimize adherence and objective measurement of adherence is critical for interpreting results. Two randomized, double-blind studies evaluating adjunctive pimavanserin in patients with schizophrenia who received stable antipsychotic treatment included measures to encourage and assess treatment adherence. Objective: This post hoc analysis evaluated adherence levels achieved in the Phase III ENHANCE study (NCT02970292) and the Phase II ADVANCE study (NCT02970305). Methods: Blood levels of participants receiving adjunctive treatment with pimavanserin or placebo added to their ongoing antipsychotic medication were tested and evaluated regularly throughout both studies. For both the background antipsychotic and pimavanserin, treatment adherence was defined as a blood sample test result above the lower limit of quantification. Results: Overall, 392 of 633 screened patients and 403 of 608 screened patients were in the safety populations in ENHANCE and ADVANCE, respectively. In ENHANCE, at weeks 1, 3, and 6/early termination (ET), the adherence rates remained ≥ 95.1% for the background antipsychotic in both pimavanserin and placebo treatment groups and ≥ 96.8% for pimavanserin. In ADVANCE, high adherence rates (≥90.6%) with the background antipsychotic (for both treatment groups) and pimavanserin (≥95.0%) were observed at weeks 2, 8, 14, and 26/ET. Conclusion: Rigorous screening was performed to exclude patients not adherent to their background antipsychotic before enrollment and to pimavanserin during study visits by using regular blood sampling. Mandatory caregiver participation further supported adherence to study treatment and procedures. These efforts may have contributed to the high levels of adherence to both background antipsychotic and pimavanserin reported in ENHANCE and ADVANCE.

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