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1.
BMC Geriatr ; 24(1): 712, 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39187760

RESUMEN

BACKGROUND: This study aims to investigate the awareness rate of six common geriatric syndromes and related influencing factors among the older adults aged 65 and above in China. METHODS: This is a multicenter cross-sectional study involving 6,653 participants aged 65 and older from four regions who completed a questionnaire on geriatric syndrome awareness. The questionnaire covered demographic data, health information, medication usage, and an assessment scale for knowledge of six geriatric syndromes (GS Awareness Scale). RESULTS: A total of 6,653 respondents were surveyed, with 5,318 valid questionnaires collected (79.93%), including 1,311 from Zhejiang (24.7%), 1,356 from Beijing (25.5%), 1,373 from Sichuan (25.8%), and 1,278 from Fujian (24.0%). The highest awareness was for falls, with 3,295 individuals (62.0%), followed by dementia with 2,929 individuals (55.1%), malnutrition with 2,907 individuals (54.7%), frailty with 2,156 individuals (40.5%), urinary incontinence with 2,006 individuals (37.7%), and sarcopenia with 1,914 individuals (36.0%). Univariate analysis showed that factors such as region, age, marital status, living situation, educational level, source of respondents, income status, and smoking had statistically significant differences in awareness rates (P < 0.05). Multivariate logistic regression results indicated that the source of respondents significantly affected the awareness rates (P < 0.05), with the older adults from rural areas having an increased risk of lower awareness compared to urban areas; age also significantly influenced the awareness rates (P < 0.05), with older age groups (76-85, 86-95 years) having a higher risk of reduced awareness compared to those aged 65-75 years. CONCLUSIONS: The awareness of common geriatric syndromes among the older adults population aged 65 years and older in China is notably low. Consequently, there exists a critical need to enhance the formulation of policies regarding geriatric syndromes across various regions, aiming to elevate health literacy among this demographic.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Humanos , Estudios Transversales , Anciano , Masculino , Femenino , China/epidemiología , Anciano de 80 o más Años , Evaluación Geriátrica/métodos , Encuestas y Cuestionarios , Síndrome , Concienciación
2.
Biochemistry ; 62(17): 2541-2548, 2023 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-37552860

RESUMEN

CRISPR-Cas9 has been adapted as a readily programmable genome manipulation agent, and continuing technological advances rely on an in-depth mechanistic understanding of Cas9 target discrimination. Cas9 interrogates a target by unwinding the DNA duplex to form an R-loop, where the RNA guide hybridizes with one of the DNA strands. It has been shown that RNA guides shorter than the normal length of 20-nucleotide (-nt) support Cas9 cleavage activity by enabling partial unwinding beyond the RNA/DNA hybrid. To investigate whether DNA segment beyond the RNA/DNA hybrid can impact Cas9 target discrimination with truncated guides, Cas9 double-stranded DNA cleavage rates (kcat) were measured with 16-nt guides on targets with varying sequences at +17 to +20 positions distal to the protospacer-adjacent-motif (PAM). The data reveal a log-linear inverse correlation between kcat and the PAM+(17-20) DNA duplex dissociation free energy (ΔGNN(17-20)0), with sequences having smaller ΔGNN(17-20)0 showing faster cleavage and a higher degree of unwinding. The results indicate that, with a 16-nt guide, "peripheral" DNA sequences beyond the RNA/DNA hybrid contribute to target discrimination by tuning the cleavage reaction transition state through the modulation of PAM-distal unwinding. The finding provides mechanistic insights for the further development of strategies that use RNA guide truncation to enhance Cas9 specificity.


Asunto(s)
Sistemas CRISPR-Cas , ARN , ARN/genética , Nucleótidos , ADN/genética , Edición Génica/métodos
3.
Artículo en Inglés | MEDLINE | ID: mdl-35805357

RESUMEN

Hydroplaning risk evaluation plays a pivotal role in highway safety management. It is also an important component in the intelligent transportation system (ITS) ensuring human driving safety. Water-film is the widely accepted vital factor resulting in hydroplaning and thus continuously gained researchers' attention in recent years. This paper provides a new framework to evaluate the hydroplaning potential based on emerging 3D laser scanning technology and water-film thickness estimation. The 3D information of the road surface was captured using a vehicle-mounted Light Detection and Ranging (LiDAR) system and then processed by a wavelet-based filter to remove the redundant information (surrounding environment: trees, buildings, and vehicles). Then, the water film thickness on the given road surface was estimated based on a proposed numerical algorithm developed by the two-dimensional depth-averaged Shallow Water Equations (2DDA-SWE). The effect of the road surface geometry was also investigated based on several field test data in Shanghai, China, in January 2021. The results indicated that the water-film is more likely to appear on the rutting tracks and the pavement with local unevenness. Based on the estimated water-film, the hydroplaning speeds were then estimated to represent the hydroplaning risk of asphalt pavement in rainy weather. The proposed method provides new insights into the water-film estimation, which can help drivers make effective decisions to maintain safe driving.


Asunto(s)
Conducción de Automóvil , Agua , China , Humanos , Rayos Láser , Lluvia
4.
Chemistry ; 26(66): 15116-15120, 2020 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-32579262

RESUMEN

Although lipids contribute to cancer drug resistance, it is challenging to target diverse range of lipids. Here, we show enzymatically inserting exceedingly simple synthetic lipids into membranes for increasing membrane tension and selectively inhibiting drug resistant cancer cells. The lipid, formed by conjugating dodecylamine to d-phosphotyrosine, self-assembles to form micelles. Enzymatic dephosphorylation of the micelles inserts the lipids into membranes and increases membrane tension. The micelles effectively inhibit a drug resistant glioblastoma cell (T98G) or a triple-negative breast cancer cell (HCC1937), without inducing acquired drug resistance. Moreover, the enzymatic reaction of the micelles promotes the accumulation of the lipids in the membranes of subcellular organelles (e.g., endoplasmic reticulum (ER), Golgi, and mitochondria), thus activating multiple regulated cell death pathways. This work, in which for the first time membrane tension is increased to inhibit cancer cells, illustrates a new and powerful supramolecular approach for antagonizing difficult drug targets.


Asunto(s)
Retículo Endoplásmico/química , Lípidos/química , Neoplasias , Preparaciones Farmacéuticas , Línea Celular Tumoral , Resistencia a Antineoplásicos , Humanos
5.
Angew Chem Int Ed Engl ; 59(38): 16445-16450, 2020 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-32521103

RESUMEN

Herein, we show that an enzymatic reaction can generate peptide assemblies that sequestrate proteins to selectively kill cancer cells. A phosphopeptide bearing the antagonistic motif (AVPI) to the inhibitors of apoptotic proteins (IAPs) enters cancer cells and normal cells by caveolin-dependent endocytosis and macropinocytosis, respectively. The AVPI-bearing peptide assemblies sequestrates IAPs and releases bortezomib (BTZ), a proteasome inhibitor, in the cytosol of cancer cells, but rescues the normal cells (namely, HS-5 cells) by trafficking the BTZ into lysosomes. Alkaline phosphatase (ALP) acts as a context-dependent signal for trafficking the peptide/BTZ assemblies and selectively induces the death of the cancer cells. The assemblies of AVPI exhibit enhanced proteolytic resistance. This work, which utilizes the difference in endocytic uptake of enzymatically formed peptide assemblies to selectively kill cancer cells, promises a new way to develop selective cancer therapeutics.


Asunto(s)
Fosfatasa Alcalina/metabolismo , Antineoplásicos/farmacología , Bortezomib/farmacología , Péptidos/farmacología , Complejo de la Endopetidasa Proteasomal/metabolismo , Inhibidores de Proteasoma/farmacología , Antineoplásicos/química , Antineoplásicos/metabolismo , Bortezomib/química , Bortezomib/metabolismo , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Células HeLa , Humanos , Estructura Molecular , Péptidos/química , Péptidos/metabolismo , Inhibidores de Proteasoma/química , Inhibidores de Proteasoma/metabolismo , Células Tumorales Cultivadas
6.
Cell Rep Phys Sci ; 1(12)2020 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-33511360

RESUMEN

Since mitochondria contribute to tumorigenesis and drug resistance in cancer, mitochondrial genetic engineering promises a new direction for cancer therapy. Here, we report the use of the perimitochondrial enzymatic noncovalent synthesis (ENS) of peptides for delivering genes selectively into the mitochondria of cancer cells for mitochondrial genetic engineering. Specifically, the micelles of peptides bind to the voltage-dependent anion channel (VDAC) on mitochondria for the proteolysis by enterokinase (ENTK), generating perimitochondrial nanofibers in cancer cells. This process, facilitating selective delivery of nucleic acid or gene vectors into mitochondria of cancer cells, enables the mitochondrial transgene expression of CRISPR/Cas9, FUNDC1, p53, and fluorescent proteins. Mechanistic investigation indicates that the interaction of the peptide assemblies with the VDAC and mitochondrial membrane potential are necessary for mitochondria targeting. This local enzymatic control of intermolecular noncovalent interactions enables selective mitochondrial genetic engineering, thus providing a strategy for targeting cancer cells.

7.
J Med Chem ; 62(22): 10245-10257, 2019 11 27.
Artículo en Inglés | MEDLINE | ID: mdl-31670952

RESUMEN

Intravenous administration of a prodrug, chloramphenicol succinate (CLsu), is ineffective. Recently, we have shown that conjugation of diglycine of CLsu (CLsuGG) not only increases the antibiotic efficacy against Escherichia coli but also reduces adverse drug effects against bone marrow stromal cells. Here, we report the synthesis of structural analogues of CLsuGG and their activities against E. coli. These analogues reveal several trends: (i) except the water-insoluble analogues, the attachment of peptides to CLsu enhances the efficacy of the prodrugs; (ii) negative charges, high steric hindrance in the side chains, or a rigid diester decreases the activities of prodrugs in comparison to CLsuGG; (iii) dipeptides apparently increase the efficacy of the prodrugs most effectively; and so forth. This work suggests that conjugating peptides to CLsu effectively modulates the properties of prodrugs. The structure-activity relationship of these new conjugates may provide useful insights for expanding the pool of antibiotics.


Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Cloranfenicol/química , Cloranfenicol/farmacología , Escherichia coli/efectos de los fármacos , Péptidos/química , Pruebas de Sensibilidad Microbiana , Relación Estructura-Actividad
8.
Angew Chem Int Ed Engl ; 58(31): 10631-10634, 2019 07 29.
Artículo en Inglés | MEDLINE | ID: mdl-31167041

RESUMEN

Antimicrobial drug resistance demands novel approaches for improving the efficacy of antibiotics, especially against Gram-negative bacteria. Herein, we report that conjugating a diglycine (GG) to an antibiotic prodrug drastically accelerates intrabacterial ester-bond hydrolysis required for activating the antibiotic. Specifically, the attachment of GG to chloramphenicol succinate (CLsu) generates CLsuGG, which exhibits about an order of magnitude higher inhibitory efficacy than CLsu against Escherichia coli. Further studies reveal that CLsuGG undergoes rapid hydrolysis, catalyzed by intrabacterial esterases (e.g., BioH and YjfP), to generate chloramphenicol (CL) in E. coli. Importantly, the conjugate exhibits lower cytotoxicity to bone marrow stromal cells than CL. Structural analogues of CLsuGG indicate that the conjugation of GG to an antibiotic prodrug is an effective strategy for accelerating enzymatic prodrug hydrolysis and enhancing the antibacterial efficacy of antibiotics.


Asunto(s)
Antibacterianos/farmacología , Escherichia coli/efectos de los fármacos , Glicilglicina/farmacología , Antibacterianos/química , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Glicilglicina/química , Células HEK293 , Células Hep G2 , Humanos , Hidrólisis , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Relación Estructura-Actividad
9.
Chembiochem ; 20(4): 526-531, 2019 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-30388302

RESUMEN

Phosphatases play an important role in cell biology, but only a few probes are suitable for selectively imaging phosphatase activity in live cells, because the current probes require cell fixation or exhibit considerable cytotoxicity. Herein, we show that conjugating a d-peptide to a quinazolinone derivative generates cell-compatible, biostable probes for imaging the phosphatase activity inside live cells. Moreover, our results show that inhibiting ectophosphatases is a critical factor for imaging intracellular phosphatases. As the first example of using selective inhibitors to ensure intracellular function of molecular probes, this work illustrates a facile approach to design molecular probes for profiling the activities of enzymes in a spatial, selective manner in a complicated environment.


Asunto(s)
Nanopartículas/química , Péptidos/química , Monoéster Fosfórico Hidrolasas/metabolismo , Línea Celular Tumoral , Colorantes Fluorescentes/química , Humanos , Microscopía Confocal , Péptidos/metabolismo , Monoéster Fosfórico Hidrolasas/química , Quinazolinonas/química
10.
J Am Chem Soc ; 140(6): 2301-2308, 2018 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-29377688

RESUMEN

As a promising molecular process for selectively inhibiting cancer cells without inducing acquired drug resistance, enzyme-instructed self-assembly (EISA) usually requires relatively high dosages. Despite its discovery 30 years ago, the translation of the knowledge about NF-κB signaling into clinic remains complicated due to the broad roles of NF-κB in cellular regulation. Here we show that integrating EISA and NF-κB targeting boosts the efficacy of EISA over an order of magnitude without compromising selectivity against cancer cells. That is, in situ enzymatic self-assembly of a tetrapeptide results in nanofibers, which hardly affect cell viability, but lead to inductive expression of tumor necrosis factor receptor 2 (TNFR2) and decreased expression of three key proteins at the upstream of NF-κB pathway in the cancer cells. Adding the inhibitors targeting NF-κB further decreases the expressions of those upstream proteins, which turns the otherwise innocuous nanofibers to being lethal to the cancer cells, likely causing necroptosis. As the first case of using supramolecular processes to enable synthetic lethality, this work illustrates a versatile approach to translate key regulatory circuits into promising therapeutic targets.


Asunto(s)
Antineoplásicos/uso terapéutico , Apoptosis/efectos de los fármacos , FN-kappa B/metabolismo , Nanofibras/uso terapéutico , Oligopéptidos/uso terapéutico , Receptores Tipo II del Factor de Necrosis Tumoral/metabolismo , Antineoplásicos/química , Biocatálisis , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Humanos , Terapia Molecular Dirigida , FN-kappa B/antagonistas & inhibidores , Nanofibras/química , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Oligopéptidos/química , Transducción de Señal
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