[Preparation and evaluation of blank and doxorubicin loaded poly (acrylic acid) microspheres for embolization]

OBJECTIVE

To prepare ion exchange doxorubicin-loaded poly (acrylic acid) microspheres (DPMs) and evaluate the properties of these chemoembolic agents.

METHODS

Poly (acrylic acid) microspheres (PMs) without drug were prepared by inverse suspension polymerization method and then doxorubicin was loaded by ion exchange mechanism to prepare DPMs. Optical microscope was used to investigate the morphology and particle size distribution of PMs and DPMs; fluorescence microscope and confocal microscope were used to observe the distribution of doxorubicin after drug loading. Elasticities of both the microspheres were evaluated by texture analyzer. High performance liquid chromatography (HPLC) method was established to determine the drug loading behavior of PMs and releasing behavior of DPMs. The in vivo embolic property was evaluated by embolizing the hepatic artery of a rabbit with 0.1 mL of DPMs.

RESULTS

PMs and DPMs were both spherical in shape, smooth in surface and dispersed well. Doxorubicin was mainly in the outer area inside of DPMs and distributed evenly. The average particle size of PMs and DPMs were (283±136) μm and (248±149) μm, respectively. PMs and DPMs both had good compression ability with the Young's modulus of (62.63±1.65) kPa and (93.94±1.10) kPa separately. PMs reached the drug loading balance at 12 h, and the entrapment efficiency was greater than 99%. Drug loading of PMs in doxorubicin solution at the concentration of 5.0 g/L and 12.5 g/L was (19.78±0.27) g/L and (49.45±0.37) g/L, respectively. Doxorubicin released slowly from DPMs in PBS and the accumulative release percentages of DPMs with corresponding drug loading were 6.82%±0.02% and 2.83%±0.10% after 24 h, respectively. Arterial angiograms showed that the hepatic artery of the rabbit was successfully embolized with DPMs.

CONCLUSION

DPMs with good performance of loading doxorubicin could be a potential embolic agent for transcatheter arterial chemoembolization.

Relative contributions of testosterone deficiency and metabolism syndrome at the risk of reduced quality of life: A cross-sectional study among Chinese mid-aged and elderly men

Testosterone deficiency and metabolism syndrome (MetS) are universal among ageing males, and they have been suggested responsible for poorer quality of life (QoL). We aimed to evaluate the relative contributions of reproductive hormones and components of MetS at the risk of reduced QoL among Chinese mid-aged and elderly men. A cross-sectional study recruited 2,364 males aged 40-79 years, and 2,165 was included for analysis eventually. The Chinese version of ageing male symptoms scale, 36-item Short Form and Beck Depression Inventory were applied to assess QoL. Bivariate correlation analysis and multiple linear regression analysis were used to assess the relative contributions of reproductive hormones and components of MetS at the risk of reduced QoL. Testosterone deficiency and MetS contributed to poorer QoL, of which higher fasting blood glucose made the primary contribution, lower total testosterone mainly contributed to poorer physical functioning.

The rs5934505 single nucleotide polymorphism (SNP) is associated with low testosterone and late-onset hypogonadism, but the rs10822184 SNP is associated with overweight and obesity in a Chinese Han population: a case-control study

Low testosterone is associated with late-onset hypogonadism (LOH) and obesity. Recently, studies have shown that four single nucleotide polymorphisms (SNPs), rs12150660, rs727428, rs5934505, and rs10822184, are associated with testosterone levels in populations of European descent. Therefore, we investigated whether the SNP loci are related to low testosterone, LOH, or obesity in a Chinese Han population. Ruling out co-morbidities, DNA was prepared from 409 men (aged 40-65 years) with low serum testosterone (defined as total testosterone <11.6 nmol/L) and 1 : 1 normal controls (matched age, body mass index (BMI), and the same living area) who were selected from 6898 males. According to the same standards, 310 men with LOH and 1 : 1 normal controls were selected from 6898 males. Excluding the cases with an unreliable sequencing result, genetic analyses were performed. The minor allele frequencies of the SNP loci rs12150660, rs727428, rs5934505, and rs10822184 were 0.1%, 44.6%, 18.7%, and 38.9%, respectively. rs5934505 was associated with the serum total testosterone and calculated free testosterone (CFT) levels (p = 0.045 and p = 0.021). rs5934505 (C>T) was associated with an increased risk of low total testosterone, low CFT, and LOH and adjusted for other factors, with an odds ratio (OR) of 2.01 (1.34-3.01), 2.14 (1.42-3.20), and 1.64 (1.04-2.58). rs10822184 was significantly correlated with weight and BMI (p = 0.035 and p = 0.027). rs10822184 (T>C) was associated with an increased risk of overweight and obesity. We adjusted for other factors, with odds ratios (ORs) of 1.94 (1.36-2.78) and 1.56 (1.00-2.43). In summary, our study provided convincing evidence that rs5934505 (C>T) was associated with the risk of low testosterone and LOH in Chinese populations. We were the first to find that rs10822184 (T>C) was significantly correlated with the risk of overweight and obesity in Chinese populations. However, further large and functional studies are warranted to confirm our findings.