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1.
Prev Med ; 178: 107813, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38092330

RESUMO

Since the 20th century, the world has undergone climate change, population growth and population aging, which may result in alterations in the epidemiology of non-optimal temperature-associated strokes. We employed multiple methodologies and data from the global burden of disease 2019 to unveil the long-term curvilinear trends in strokes attributed to non-optimal temperature and the impact of aging and population growth on its changing epidemiology. From 1990 to 2019, the age-standardized DALYs rate (ASDR) of strokes attributable to low temperature had been decreasing, but from 2016, the continued downward trend in ASDR disappeared and began to remain stable. On the contrary, the ASDR of strokes attributable to high temperature continued to increase. The high socio-demographic index (SDI) region experienced the fastest decreased trend. The disease burden of stroke attributable to low temperature is increased by aging in 178 countries (87.25%), compared with 130 (63.73%) for high temperature. After excluding aging and population growth, the DALY rate for strokes attributed to high temperature was increasing in 87 countries and territories (42.64%). The disease burden of strokes attributed to low temperature is far greater than that of high temperature in absolute figures. However, globally, there is a significant trend toward an increase in strokes attributed to high temperature. Social development has largely offset the burden of strokes attributed to low temperature, but most regions of the world are equally affected by strokes attributed to high temperature. Simultaneously, in the framework of climate change, aging is also largely hindering stroke prevention efforts.


Assuntos
Carga Global da Doença , Acidente Vascular Cerebral , Humanos , Anos de Vida Ajustados por Qualidade de Vida , Temperatura , Crescimento Demográfico , Acidente Vascular Cerebral/epidemiologia , Saúde Global , Envelhecimento
2.
J Gastroenterol Hepatol ; 39(5): 880-892, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38221664

RESUMO

BACKGROUND: The disease burden of colorectal cancer in East Asia has been at a high level. However, the epidemiological characteristics of the disease burden in this region have not been systematically studied. METHOD: Data were obtained from the Global Burden of Disease 2019 program. Joinpoint analysis was used to identify long-term trends in mortality of colorectal cancer. Independent effects of age, period, and cohort were detected by the age-period-cohort model. The Bayesian age-period-cohort model was performed to predict the burden of colorectal cancer across East Asia by 2030. RESULTS: From 1990 to 2019, the average annual percentage change (AAPC) showed upward trends in mainland China (1.05 [95% confidence interval (CI)], 0.82, 1.28) as well as Taiwan Province of China (1.81 [95% CI], 1.51, 2.10) but downward in Japan (-0.60 [95% CI], -0.70, -0.49) (P < 0.05). Attributable risk factors for colorectal cancer in East Asia remained stable over 30 years, while the risk of metabolic factors is noteworthy in the future. In the next decade, the age-standardized death rate (ASDR) of colorectal cancer in China was predicted to surpass that of Japan and South Korea in expectation. CONCLUSION: The mortality of colorectal cancer is escalating in developing countries, while it is gradually declining in high-income countries across East Asia. Nonetheless, the disease burden of colorectal cancer in high-income countries remains substantial level.


Assuntos
Neoplasias Colorretais , Humanos , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/etiologia , Neoplasias Colorretais/mortalidade , Fatores de Risco , Pessoa de Meia-Idade , Masculino , Feminino , Idoso , Fatores de Tempo , Ásia Oriental/epidemiologia , Fatores Etários , Adulto , Teorema de Bayes , Carga Global da Doença/tendências , China/epidemiologia , Idoso de 80 Anos ou mais
3.
Int J Environ Health Res ; : 1-12, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38576314

RESUMO

Limited studies in China have explored the association between gravidae exposure to PM2.5 and small for gestational age infants (SGA), yielding inconsistent results. This study in Wuhan utilized daily excessive concentration hours (DECH) as a novel measure to assess PM2.5's impact on SGA. Data on air pollutants and pregnant women were collected from the Wuhan Municipal Ecology and Environmental Bureau and Wuhan Children's Hospital, respectively. Logistic regression models were employed to evaluate the contribution of PM2.5-DECH and PM2.5-mean to SGA. Significant correlations were observed between PM2.5-mean and SGA during the second trimester [OR = 1.23 (95% CI: 1.14-1.32)] and the entire pregnancy [OR = 1.15 (95% CI: 1.07-1.24)]. Similar correlations were found between PM2.5-DECH and SGA. These findings suggest that increased PM2.5 exposure is associated with a higher risk of SGA, and DECH may be used as a prospective substitute indicator for daily average concentration in similar studies.

4.
Opt Express ; 31(2): 2195-2207, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785238

RESUMO

CsPbBr3 perovskite quantum dots (PQDs) as promising color conversion materials have been widely used in display and visible light communication (VLC), but most CsPbBr3 PQDs for VLC are randomly selected without optimization. Thereby the exploration of fundamental experimental parameters of QDs is essential to better employ their performance advantages. Herein, we investigated the concentration and solvent effects on photoluminescence (PL) properties and communication performance of CsPbBr3 PQDs. The PL, time-resolved PL characterization and communication measurements of CsPbBr3 PQDs all exhibit concentration dependence, suggesting that there exists an optimum concentration to take advantages of performance merits. CsPbBr3 PQDs with a concentration of 0.5 mg/ml show the shortest carrier lifetime and achieve the highest -3 dB bandwidth (168.03 MHz) as well as the highest data rate (660 Mbps) comparing to other concentrations. And in terms of the optimal concentration, we further explored the approach to improve the communication performance, investigating the effect of polarity solvent on the communication performance of CsPbBr3 PQDs. Original 0.5 mg/ml CsPbBr3 PQDs (1 ml) with 55 µL ethanol added in obtain a higher -3 dB bandwidth of 363.68 MHz improved by ∼116.4% and a record data rate of 1.25 Gbps improved by ∼89.4% but weaker PL emission due to energy transfer. The energy transfer assisted improvement may open up a promising avenue to improve the communication performance of QDs, but more feasible energy transfer path needs to be explored to ensure the stability of QDs.

5.
Opt Lett ; 48(8): 2026-2029, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-37058633

RESUMO

In this paper, we fabricated a 3×3 violet series-biased micro-LED array with high-output optical power and applied it in high-speed and long-distance visible light communication. By employing the orthogonal frequency division multiplexing modulation scheme, distance adaptive pre-equalization, and a bit-loading algorithm, record data rates of 10.23 Gbps, 10.10 Gbps, and 9.51 Gbps were achieved at 0.2 m, 1 m, and 10 m, respectively, below the forward error correction limit of 3.8×10-3. To the best of our knowledge, these are the highest data rates achieved by violet micro-LEDs in free space and the first communication demonstration beyond 9.5 Gbps at 10 m using micro-LEDs.

6.
Opt Lett ; 48(11): 2861-2864, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37262229

RESUMO

InGaN-based micro-LEDs can detect and emit optical signals simultaneously, owing to their overlapping emission and absorption spectra, enabling color detection. In this paper, we fabricated a green InGaN-based micro-LED array with integrated emission and detection functions. On the back side of the integrated device, when the 80 µm micro-LED emitted light, the 200 µm LED could receive reflected light to accomplish color detection. The spacing between the 80 µm and the 200 µm micro-LEDs was optimized to be 1 mm to reduce the effect of the direct light transmitted through the n-GaN layer without reflection. The integrated device shows good detection performance for different colors and skin colors, even in a dark environment. In addition, light can be emitted from the top side of the device. Utilization of light from both sides of the integrated device provides the possibility of its application in display, communication, and detection on the different sides.

7.
Opt Lett ; 48(18): 4845-4848, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37707918

RESUMO

Sidewall defects play a key role in determining the efficiency of GaN-based micro-light emitting diodes (LEDs) for next generation display applications, but there still lacks direct observation of defects-related recombination at the affected area. In this Letter, we proposed a direct technique to investigate the recombination mechanism and size effect of sidewall defects for GaN blue micro-LEDs. The results show that mesa etching will produce stress release near the sidewall, which can reduce the quantum confinement Stark effect (QCSE) to improve the radiative recombination. Meanwhile, the defect-related non-radiative recombination generated by the sidewall defects plays a leading role under low-power injection. In addition, the effective area of the mesas affected by the sidewall defects can be directly observed according to the fluorescence lifetime imaging microscope (FLIM) characterization. For example, the effective area of the mesa with 80 µm is affected by 23% while the entire area of the mesa with 10 µm is almost all affected. This study provides guidance for the analysis and repair of sidewall defects to improve the quantum efficiency of micro-LEDs display at low current density.

8.
J Org Chem ; 88(12): 7641-7650, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35960861

RESUMO

A series of compounds featuring a novel bispiro[indanedione-oxindole-cyclopropane] moiety have been synthesized through a squaramide-catalyzed [2+1] cycloaddition reaction. The tandem Michael-alkylation reaction of 2-arylidene-1,3-indanediones with 3-bromooxindoles furnished the cycloadducts in high yields with excellent diastereo- and enantioselectivities. The ammonium ylide in the catalytic process, as a key intermediate, was revealed by the high-resolution mass spectrometry study.


Assuntos
Reação de Cicloadição , Estereoisomerismo
9.
Prev Med ; 175: 107689, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37652107

RESUMO

BACKGROUND: Previous investigations have predominantly concentrated on the influence of ozone (O3) on general population mortality. However, a noticeable gap exists regarding the attention directed towards susceptible demographics, specifically individuals afflicted by human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS). METHODS: A dataset comprising 1467 AIDS-related fatalities from 2013 to 2020 was amassed from the Hubei Provincial Center for Disease Control and Prevention. Daily maximum 8-h average O3 levels and meteorological parameters were extracted from the ChinaHighAirPollutants dataset and the National Meteorological Science Data Center, respectively. A time-stratified case-crossover methodology was employed to scrutinize the connection between short-term exposure to O3 and AIDS-related deaths. RESULTS: A rise of one interquartile (IQR) in O3 concentration, lagged by 4 days, was associated with a 15% [95% confidence intervals (CIs): 2, 31] increase in AIDS-related deaths. Notably, males demonstrated heightened susceptibility to the adverse consequences of O3, marked by an odds ratio of 1.20 (95% CIs: 1.05, 1.37) at lag 4 day. Additionally, patients aged over 65 years exhibited escalated vulnerability to brief O3 exposure. Marriage status and educational attainment emerged as influential factors modifying the interplay between O3 and AIDS-related mortality. CONCLUSIONS: Our study presents novel evidence spotlighting the deleterious repercussions of O3 on mortality in the HIV/AIDS population.

10.
J Biomech Eng ; 145(12)2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37578172

RESUMO

Ossification of the posterior longitudinal ligament (OPLL) has been identified as an important cause of cervical myelopathy. However, the biomechanical mechanism between the OPLL type and the clinical characteristics of myelopathy remains unclear. The aim of this study was to evaluate the effect of different types of OPLL on the dynamic biomechanical response of the spinal cord. A three-dimensional finite element model of the fluid-structure interaction of the cervical spine with spinal cord was established and validated. The spinal cord stress and strain, cervical range of motion (ROM) in different types of OPLL models were predicted during dynamic flexion and extension activity. Different types of OPLL models showed varying degrees of increase in stress and strain under the process of flexion and extension, and there was a surge toward the end of extension. Larger spinal cord stress was observed in segmental OPLL. For continuous and mixed types of OPLL, the adjacent segments of OPLL showed a dramatic increase in ROM, while the ROM of affected segments was limited. As a dynamic factor, flexion and extension of the cervical spine play an amplifying role in OPLL-related myelopathy, while appropriate spine motion is safe and permitted. Segmental OPLL patients are more concerned about the spinal cord injury induced by large stress, and patients with continuous OPLL should be noted to progressive injuries of adjacent level.


Assuntos
Ossificação do Ligamento Longitudinal Posterior , Doenças da Medula Espinal , Humanos , Ligamentos Longitudinais/fisiologia , Análise de Elementos Finitos , Osteogênese , Doenças da Medula Espinal/etiologia , Ossificação do Ligamento Longitudinal Posterior/complicações , Vértebras Cervicais
11.
Ecotoxicol Environ Saf ; 258: 114962, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37121078

RESUMO

BACKGROUND: As the world experiences a demographic shift towards aging populations, there will be a significant surge in the number of sarcopenia patients, along with an unprecedented expansion in the associated economic burden. The multitudinous risk factors for sarcopenia have been reported, but evidence for air pollution remains rare. METHODS: This cross-sectional study employed multi-stage random sampling to select 1592 participants over 40 years of age from Hubei Province. Daily mean concentrations of air pollutants were collected ChinaHighAirPollutants dataset. Unconditional logistic regression models were utilized to investigate the associations between air pollution and sarcopenia. RESULTS: For each 1 µg/m3 increase in PM2.5, PM10, SO2 and O3, there were corresponding elevations of 11.1% [95% confidence interval (CI): 4.9, 17.7], 4.3% (95% CI: 1.4, 7.2), 22.6% (95% CI: 7.2, 40.1) and 9.3% (95% CI: 0.7, 18.7) in the risk of sarcopenia, respectively. The associations of PM2.5/PM10/O3-sarcopenia were more pronounced in females, with corresponding odds ratios (ORs) and 95% CIs of 1.179 (1.062, 1.310), 1.079 (1.027, 1.135) and 1.180 (1.026, 1.358), separately. Additionally, individuals residing in rural areas were more susceptible to the effects of PM2.5 and PM10. Current/ever smokers or drinkers were also at higher risk of developing sarcopenia caused by PM2.5, PM10 and O3 exposure. Mixture analyses show a surge of 48.4% (95% CI: 3.6%, 112.5%) in the likelihood of suffering from sarcopenia, and the joint impacts of the air pollution were mainly driven by PM2.5. CONCLUSIONS: Our results produced evidence for a relationship between air pollution exposure and the increased prevalence of sarcopenia in China. Public health and relevant departments should make efforts to prevent sarcopenia, particularly in China experiencing rapid demographic aging.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Sarcopenia , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Estudos Transversais , Sarcopenia/etiologia , Sarcopenia/induzido quimicamente , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , China/epidemiologia , Material Particulado/efeitos adversos , Material Particulado/análise , Músculos/química , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Dióxido de Nitrogênio/análise
12.
Geriatr Nurs ; 51: 54-64, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36893611

RESUMO

OBJECTIVE: The aim of this review was to evaluate the overall diagnostic performance of e-devices for detection of health problems in older adults at home. METHODS: A systematic review was conducted following the PRISMA-DTA guidelines. RESULTS: 31 studies were included with 24 studies included in meta-analysis. The included studies were divided into four categories according to the signals detected: physical activity (PA), vital signs (VS), electrocardiography (ECG) and other. The meta-analysis showed the pooled estimates of sensitivity and specificity were 0.94 and 0.98 respectively in the 'VS' group. The pooled sensitivity and specificity were 0.97 and 0.98 respectively in the 'ECG' group. CONCLUSIONS: All kinds of e-devices perform well in diagnosing the common health problems. While ECG-based health problems detection system is more reliable than VS-based ones. For sole signal detection system has limitation in diagnosing specific health problems, more researches should focus on developing new systems combined of multiple signals.


Assuntos
Exercício Físico , Humanos , Idoso , Sensibilidade e Especificidade
13.
Plant Foods Hum Nutr ; 78(2): 261-269, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37410257

RESUMO

Fermented soybean foods with a long history are popular worldwide because of rich nutrition. However, many traditional fermented soybean foods have unacceptable bitterness, which mostly comes from the bitter peptides produced from the hydrolysis of soybean proteins. In this review, the bitter peptides in fermented soybean foods is briefly reviewed. The structural properties of bitter receptors and bitter peptides were reviewed. Bitterness is perceived through the binding between bitter compounds and specific sites of bitter receptors (25 hTAS2Rs), which further activate the downstream signal pathway mediated by G-protein. And it converts chemical signals into electrical signals, and transmit them to the brain. In addition, the influencing factors of bitter peptides in fermented soybean foods were summarized. The bitterness of fermented soybean foods primarily results from the raw materials, microbial metabolism during fermentation, unique techniques, and interactions of various flavor compounds. Moreover, the structure-bitterness relationship of bitter peptides was also discussed in this review. The bitterness degree of the bitter peptide is related to the polypeptide hydrophobicity, amino acids in the peptide, peptide molecular weight and polypeptide spatial structure. Studying the bitter peptides and their bitter characteristics in fermented soybean foods is beneficial for improving the sensory quality of fermented soybean foods and prompting more consumers accept them.


Assuntos
Alimentos Fermentados , Glycine max , Peptídeos/metabolismo , Paladar , Proteínas de Soja
14.
Opt Express ; 30(24): 44260-44269, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36523104

RESUMO

In this work, we demonstrated a convenient and reliable method to realize the vertical stack integration of the blue and yellow InGaN micro-LED arrays. The standard white and color-tunable micro-light sources can be achieved by adjusting the current densities injection of the micro-LEDs. The spectra cover violet, standard white, cyan, etc., showing an excellent color-tunable property. And the mixed standard white light can be separated into red-green-blue three primary colors through the color filters to realize full-color micro-LED display with a color gamut of 75% NTSC. Besides, the communication capability of the integrated micro-LED arrays as visible light communication (VLC) transmitters is demonstrated with a maximum total data rate of 2.35 Gbps in the wavelength division multiplexing (WDM) experimental set-up using orthogonal frequency division multiplexing modulation. In addition, a data rate of 250 Mbps is also realized with the standard white light using on-off keying (OOK) modulation. This integrated device shows great potential in full-color micro-LED display, color-tunable micro-light sources, and high-speed WDM VLC multifunctional applications.

15.
Opt Express ; 30(20): 36403-36413, 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36258569

RESUMO

Micro-LED has attracted tremendous attention as next-generation display, but InGaN red-green-blue (RGB) based high-efficiency micro-LEDs, especially red InGaN micro-LED, face significant challenges and the optoelectronic performance is inevitably affected by environmental factors such as varying temperature and operating current density. Here, we demonstrated the RGB InGaN micro-LEDs, and investigated the effects of temperature and current density for the InGaN RGB micro-LED display. We found that temperature increase can lead to the changes of electrical characteristics, the shifts in electroluminescence spectra, the increase of full width at half maximum and the decreases of light output power, external quantum efficiency, power efficiency, and ambient contrast ratios, while current density increase can also give rise to different changing trends of the varieties of parameters mentioned just above for the RGB micro-LED display, creating great challenges for its application in practical scenarios. Despite of the varying electrical and optical charateristics, relatively high and stable colour gamut of the RGB display can be maintained under changing temperature and current density. Based on the results above, mechanisms on the temperature and current density effects were analyzed in detail, which would be helpful to predict the parameters change of micro-LED display caused by temperature and current density, and provided guidance for improving the performance of InGaN micro-LED display in the future.

16.
Osteoporos Int ; 33(11): 2357-2368, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35831465

RESUMO

We hypothesized that air pollution could cause oxidative damage and inflammation in the human body, which was linked to bone loss. Our result showed that long-term exposure to air pollution might decrease bone mineral density (BMD) T-score and increase the prevalence of osteoporosis in Hubei province. INTRODUCTION: Osteoporosis is becoming an increasingly serious public health problem with the advent of global aging. Long-term exposure to air pollution has been linked to multitudinous adverse health outcomes, but evidence is still relatively limited and inconsistent for BMD T-score and osteoporosis. This study aimed at exploring the associations between long-term exposure to air pollution and BMD T-score and osteoporosis. METHODS: The Hubei part of the China Osteoporosis Prevalence Study was extracted. Data on air pollutants were collected by the national air quality real-time release platform of China Environmental Monitoring Station. Linear mixed models and multilevel logistic regression analyses were performed to assess the associations between air pollution and BMD T-score and osteoporosis, respectively. Subgroup analyses were conducted to identify vulnerable populations. RESULTS: A total of 1845 participants were included in this cross-section study. Per 10 ug/m3 increase in PM2.5 and SO2 were associated with 0.20 (95% CI: 0.04, 0.36) and 0.31 (95% CI: 0.11, 0.51) decrease in BMD T-score of the neck of femur, respectively. Per 10 ug/m3 increase in CO was linked with 0.03 (95% CI: 0.02, 0.05) decrease in BMD T-score of the total hip. Per 1 ug/m3 increase in PM2.5 was associated with 5% increase in the prevalence of osteoporosis in all participants. In general, the higher concentrations of PM2.5 with the more adverse effect on osteoporosis (P for trend = 0.01). The impact of PM2.5 on osteoporosis in males was higher than that in females [1.29, 95% CI (1.11, 1.50) vs 1.01, 95% CI (0.95, 1.07)]. Per 1 ug/m3 increase in PM10 corresponded with 4% elevation in the risks of osteoporosis in rural population. The ORs (95% CI) for the association of osteoporosis and NO2 in ever/current smoking and drinking population were 1.07 (1.01, 1.13) and 1.05 (1.00, 1.09), respectively. SO2 had a statistically significant positive effect on people with comorbidity [OR = 1.10, (95% CI: 1.00 to 1.21)], while none in people without comorbidity [OR = 0.96, (95% CI: 0.88 to 1.05)]. CONCLUSION: Our study provided evidence that long-term exposure to PM2.5 was linked with the decreased BMD T-score and increased risk of osteoporosis among all participants. The adverse impacts of PM2.5, PM10, and NO2 were larger in males than in females. People having comorbidity, living in rural areas, and current/ever smoking or drinking were more vulnerable to air pollution. Public health departments should consider air pollution to formulate better preventive measures for osteoporosis.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Osteoporose , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Densidade Óssea , China/epidemiologia , Estudos Transversais , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Feminino , Humanos , Masculino , Dióxido de Nitrogênio/efeitos adversos , Dióxido de Nitrogênio/análise , Osteoporose/induzido quimicamente , Osteoporose/etiologia , Material Particulado/efeitos adversos , Prevalência
17.
Opt Lett ; 47(2): 317-320, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35030596

RESUMO

In this Letter, high-speed optical wireless communication (OWC) with three light-emitting diodes (LED) and five micro-LEDs (µLEDs) is proposed as a proof-of-concept wavelength division multiplexing (WDM) system. It covers a wide spectrum from deep ultraviolet (UV) to visible light and thus could offer both visible light communication (VLC) and UV communication simultaneously. An aggregated data rate of up to 25.20 Gbps over 25 cm free space is achieved, which, to the best of our knowledge, is the highest data rate for LED-based OWC ever reported. Among them, the five µLEDs offer a data rate of up to 18.43 Gbps, which, to the best of our knowledge, is the highest data rate for µLED-based OWC so far. It shows the superiority and potential of µLEDs for WDM-OWC. Additionally, a data rate of 20.11 Gbps for VLC is achieved.

18.
Pharmacol Res ; 186: 106522, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36283629

RESUMO

Cancer is complicated to treat because of its high propensity for recurrence and metastasis, and various side effects of conventional cancer treatments. With the development of nanotechnology, biology, material science and pharmacy, nanoparticles emerge as a promising method to load anti-cancer drugs to deal with the downsides of conventional treatments. Among the various class of nanoparticles, endogenous stimuli-responsive nanoparticles exert significant anti-cancer effects by releasing drugs due to the stimulations from pH gradient, redox as well as other enzymes of cancer microenvironment. Extraordinary progress has been achieved as the latest endogenous stimuli-responsive nanoparticles exhibit better therapeutic effects, lower toxicity, and superior biocompatibility, indicating brighter prospects for cancer therapy. However, these stimuli-responsive nanoparticles are still not ready for large-scale clinical application, due to reasons such as the lack of clinical trials and high cost of manufacturing. Here, we consolidate the advancements and limitations of various endogenous stimuli-responsive nanoparticles, as well as critically discuss the prospects of this kind of nanoparticles in tumor treatments.


Assuntos
Antineoplásicos , Nanopartículas , Neoplasias , Humanos , Sistemas de Liberação de Medicamentos , Nanopartículas/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Nanotecnologia , Portadores de Fármacos/uso terapêutico , Microambiente Tumoral
19.
J Org Chem ; 87(22): 15210-15223, 2022 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-36305826

RESUMO

The first enantioselective formal (3 + 2) cyclocondensation involving α,ß-unsaturated pyrazoleamides as 3-carbon partners was accomplished in a stepwise fashion. The stepwise esterification/Michael addition sequence is promoted by Zn(OTf)2 and quinine-squaramide derivative, respectively. The protocol enables access to spiro-fused pentacyclic spirooxindoles from coumarin-3-formylpyrazoles and 3-hydroxyoxindoles in good to satisfactory overall yields (up to 91%) with excellent dr (all cases >20:1 dr) and high ee values (up to 99%). Mechanistic investigations contributed to shedding light on the enantioselective event of the process.


Assuntos
Carbono , Cumarínicos , Estereoisomerismo , Esterificação , Catálise
20.
J Org Chem ; 87(23): 16047-16053, 2022 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-36354352

RESUMO

Unlike reported pyridine hybrids, 2S (1a) and 2R-alanginenmine A (1b) from Alangium chinense featuring an unprecedented piperidine-bridged polypyridine skeleton represented a pair of alkaloid subtypes with a unique multiple pyridine scaffold. Enlightened by the rare structural characteristics and possible biosynthetic pathway, (±)-alanginenmine A (1) have been achieved in ideal yield by gram-class total synthesis with four steps. In addition, both compounds 1a and 1b exhibited anti-acetylcholinesterase (AChE) and HIV-1 protease activities in the biological activity evaluation. Further, molecular docking was investigated for the mechanism of action between the isolated compounds and HIV-1 protease. The stronger Coulomb interactions and van der Waals interaction, as well as the hydrogen bond interactions of 1a, might be the main cause for its better anti-HIV-1 protease activity than 1b. This work provided a comprehensive research including natural product discovery, bioactivity evaluation, and total synthesis for the new type of leading anti-HIV-1 protease.


Assuntos
Alangiaceae , Inibidores da Protease de HIV , HIV-1 , Acetilcolinesterase/metabolismo , Alangiaceae/metabolismo , Simulação de Acoplamento Molecular , Piridinas/farmacologia
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