Changing patterns of nasopharyngeal carcinoma incidence in Hong Kong: a 30-year analysis and future projections.

BACKGROUND: This study aims to evaluate the relationship between age, period, and birth cohort with the incidence trends of Nasopharyngeal Carcinoma (NPC) in Hong Kong, make projections through 2030 and parse the drivers of the incidence. METHODS: Using data from the Hong Kong Cancer Registry, we used an age-period-cohort model to uniquely estimate age, period, and cohort effects on NPC incidence trends and make projections. We further assessed the drivers of NPC incidence using a validated decomposition algorithm. RESULTS: From 1991 to 2020, crude and age-standardized incidence rates of NPC decreased significantly. The net drifts showed significant downward trends for both sexes, and local drift declined in all age groups. Period and cohort rate ratios revealed monotonic declining patterns for both sexes. Projections suggested that NPC incidence will continue to decline. Population decomposition showed that while population growth and ageing have led to an increase in NPC cases, epidemiologic changes offset these increases, resulting in an encouraging downward trend in the incidence and new NPC cases in Hong Kong. CONCLUSIONS: The period and cohort risk of NPC in Hong Kong decreased, and epidemiologic changes offset the contribution of demographic factors, resulting in a continued decline in NPC incidence and cases.

IR780-doped cobalt ferrite nanoparticles@poly(ethylene glycol) microgels as dual-enzyme immobilized micro-systems: Preparations, photothermal-responsive dual-enzyme release, and highly efficient recycling.

To solve the problems of separating dual enzymes from the carriers of dual-enzyme immobilized micro-systems and greatly increase the carriers' recycling times, photothermal-responsive micro-systems of IR780-doped cobalt ferrite nanoparticles@poly(ethylene glycol) microgels (CFNPs-IR780@MGs) are prepared. A novel two-step recycling strategy is proposed based on the CFNPs-IR780@MGs. First, the dual enzymes and the carriers are separated from the reaction system as a whole via magnetic separation. Second, the dual enzymes and the carriers are separated through photothermal-responsive dual-enzyme release so that the carriers can be reused. Results show that CFNPs-IR780@MGs is 281.4 ± 9.6 nm with a shell of 58.2 nm, and the low critical solution temperature is 42 °C, and the photothermal conversion efficiency increases from 14.04% to 58.41% by doping 1.6% of IR780 into the CFNPs-IR780 clusters. The dual-enzyme immobilized micro-systems and the carriers are recycled 12 and 72 times, respectively, and the enzyme activity remains above 70%. The micro-systems can realize whole recycling of the dual enzymes and carriers and further recycling of the carriers, thus providing a simple and convenient recycling method for dual-enzyme immobilized micro-systems. The findings reveal the micro-systems' important application potential in biological detection and industrial production.

Trends and Projections of Stomach Cancer Incidence in Hong Kong: A Population-Based Study.

OBJECTIVES: The burden of stomach cancer remains high in Hong Kong. We sought to evaluate the associations of age, period, and birth cohort with the changing trend in the incidence of stomach cancer and to provide projections through 2030. MATERIALS AND METHODS: We performed an age-period-cohort analysis and projections up to 2030 using data from the Hong Kong Cancer Registry. Additionally, we used a population decomposition algorithm to assess the drivers in the number of incident cases of stomach cancer in Hong Kong. RESULTS: Among the 26,813 stomach cancer patients, from 1994 to 2018, the age-standardized incidence rate of stomach cancer decreased for both sexes. The incidence increased with age and was highest for those aged 85 years or older. Period relative risk (RR) showed a monotonic decreasing pattern throughout the study period for both sexes before 2010. Cohort RR for males was monotonically decreasing but changed little after the 1967-1971 birth cohort. In contrast, cohort RR for females declined in the pre-1927-1931 birth cohort but slowed down since. It is projected that there will be 906 male patients and 954 female patients in 2030. Decomposition analysis suggested that population growth and aging were associated with substantial changes in the number of incident cases of stomach cancer in Hong Kong. CONCLUSIONS: Both period and cohort risk of developing stomach cancer in Hong Kong have slowed down or plateaued. Our study demonstrates that population aging and growth are the main drivers of the increased number of incident cases of stomach cancer in Hong Kong.

Accurate and Real-Time Detection Method for the Exothermic Behavior of Enzymatic Nano-Microregions Using Temperature-Sensitive Amino-AgInS2 Quantum Dots.

The thermal behavior of enzymes in nanoscale is of great significance to life phenomena. This nonequilibrium state real-time thermal behavior of enzymes at nanoscale cannot be accurately detected by existing methods. Herein, a novel method is developed for the detection of this thermal behavior. The enzyme-quantum dot (QD) conjugates can be obtained by chemically grafting temperature-sensitive amino-AgInS2 QDs to the enzyme, where the QDs act as nanothermometers with a sensitivity of -2.82% °C-1 . Detecting the photoluminescence intensity changes of the enzyme-QD conjugates, the real-time thermal behavior of enzymes can be obtained. The enzyme-QD conjugates show a temperature difference as high as 6 °C above ambient temperature in nano-microregions with good reproducibility (maximum error of 4%) during catalysis, while solution temperature hardly changed. This method has a temperature resolution of ≈0.5 °C with a detection limit of 0.02 mg mL-1 of enzyme, and spatially ensured that the amino-AgInS2 QDs are quantitatively bound to the enzyme; thus, it can accurately detect the exothermic behavior of the enzyme and can be extended to other organisms' detection. This method has high sensitivity, good stability, and reliability, indicating its great potential application in investigating the thermal behavior of organisms in nanoscale and related life phenomena.

Ultrathin surface coated water-soluble cobalt ferrite nanoparticles with high magnetic heating efficiency and rapid in vivo clearance.

To obtain magnetic nanoparticles with high magnetic heating efficiency and rapid in vivo clearance, this study utilized an improved linear response theory model to theoretically simulate the specific absorption rate (SAR) value versus the particle size of cobalt ferrite nanoparticles (CFNPs). An accurate SAR curve consistent with experimental results was obtained using cubes instead of spheres as the shape of CFNPs, given that cube was closer to the actual shape of prepared CFNPs. Under the guidance of simulation, we predicted and prepared water-soluble cubic CFNPs of 10-13 nm in size, with an ultrathin surface coating less than 1 nm in thickness. These CFNPs were experimentally verified to have high magnetic heating efficiency and rapid in vivo clearance rate. Our CFNPs of 11.8 nm in size had a high intrinsic loss power of 12.11 nHm2/kg. Most of the cells were killed within 30 min under magnetic heating with CFNPs. In an in vivo study, these CFNPs can heat a tumor area to 45 °C (ΔT > 9 °C) within 120 s under a weak alternating magnetic field (27 kA/m, 115 kHz). Notably, these CFNPs had significant tumor inhibition rate in vivo and can be cleared from the body by more than 64% within 2 weeks, demonstrating excellent rapid in vivo clearance. This result was close to the clearance level of the magnetic resonance imaging contrast agent Feridex. Therefore, our CFNPs had high magnetic heating efficiency and rapid in vivo clearance rate, indicating their great potential for future clinical applications.

Accurate intracellular and in vivo temperature sensing based on CuInS2/ZnS QD micelles.

Accurate and sensitive temperature sensing is of great importance for studying biological activities in cells and tissues. Due to the complexity of the microenvironments, most of the existing thermometry systems cannot meet the needs of accurate intracellular and in vivo temperature sensing with high-sensitivity and low-toxicity. After investigation, we found that the fluorescence intensity of CuInS2/ZnS quantum dots (QDs) is significantly temperature dependent, and these QDs can be used for intracellular and in vivo temperature sensing after being encapsulated by amphiphilic micelles (QD-micelles). These QD-micelles have a size of approximately 10.1 ± 2.5 nm and an emission band of approximately 650 nm with intense photoluminescence (PL). Meanwhile, its high thermal sensitivity of 2% °C-1 at near-room temperature is insensitive to solution pH, ionic strength, and protein concentration. Even at a concentration of 300 µg mL-1, our QD-micelles do not exert cytotoxic effects on HeLa and PC-3 cells. Similar to being dispersed in water, the QD-micelles continue to exhibit a high thermal sensitivity of 2.0% °C-1 intracellular and 2.1% °C-1 in tumor tissues, and the PL intensity (I) and temperature (T) over the physiological temperature range have a good linear correlation. Therefore, they have considerable potential in biomedical applications.

Temperature-triggered enzyme immobilization and release based on cross-linked gelatin nanoparticles.

A glucoamylase-immobilized system based on cross-linked gelatin nanoparticles (CLGNs) was prepared by coacervation method. This system exhibited characteristics of temperature-triggered phase transition, which could be used for enzyme immobilization and release. Their morphology and size distribution were examined by transmission electron microscopy and dynamic light scattering particle size analyzer. Their temperature-triggered glucoamylase immobilization and release features were also further investigated under different temperatures. Results showed that the CLGNs were regularly spherical with diameters of 155±5 nm. The loading efficiencies of glucoamylase immobilized by entrapment and adsorption methods were 59.9% and 24.7%, respectively. The immobilized enzyme was released when the system temperature was above 40°C and performed high activity similar to free enzyme due to the optimum temperature range for glucoamylase. On the other hand, there was no enzyme release that could be found when the system temperature was below 40°C. The efficiency of temperature-triggered release was as high as 99.3% for adsorption method, while the release of enzyme from the entrapment method was not detected. These results indicate that CLGNs are promising matrix for temperature-triggered glucoamylase immobilization and release by adsorption immobilization method.

Dyads and triads containing perylenetetracarboxylic diimide and porphyrin: efficient photoinduced electron transfer elicited via both excited singlet states.

Synthesis, characterizations, and photophysical properties of new photoactive dyads and triads containing perylenetetracarboxylic diimide (PIm) and porphyrin (free-base porphyrin (H(2)P) and zinc porphyrin (ZnP)), in which both entities were connected with a short ether bond, were examined with the aim of using these systems for molecular photonics. The porphyrin(P)-PIm systems absorbed strongly across the visible region, which greatly matched the solar spectrum. The geometric and electronic structures of the dyads and triads were probed using density function theory method at the B3LYP/3-21G level. It was revealed that the majority of the highest-occupied molecular orbital was located on the porphyrin entity, while the lowest-unoccupied molecular orbitals were entirely on the PIm entity. The excited-state electron-transfer processes were monitored by both steady-state and time-resolved emission as well as transient-absorption techniques in polar solvent benzonitrile. Upon excitation of the P (H(2)P and ZnP) moieties, efficient fluorescence quenching of the P moiety was observed, suggesting that the main quenching paths involved charge separation from the excited singlet porphyrin ((1)P) to the PIm moiety. Upon excitation of the PIm moiety, fluorescence quenching of the (1)PIm moiety was also observed. The nanosecond transience of spectra in near-IR region revealed the charge separation process from the P moieties to the PIm moiety via their excited singlet states. The lifetimes of the charge-separated states were evaluated to be 7-14 ns, depending on the solvent polarity. Photosensitized electron mediation systems were also revealed in the presence of methyl viologen and sacrificial electron donor.