[Effect of corneal e-value on myopia control in children and adolescents with orthokeratology].

Objective: To investigate the influence of corneal e-value on the effectiveness of orthokeratology in controlling myopia in children and adolescents. Methods: A retrospective cohort study was conducted, involving the data from 1 563 myopic patients (1 563 eyes) who underwent orthokeratology at the Affiliated Eye Hospital of Shandong University of Traditional Chinese Medicine from June 2015 to August 2021 and adhered to lens wear for at least 2 years. The cohort consisted of 737 males and 826 females with an average age of (10.84±2.13) years. Based on corneal e-value parameters obtained from corneal topography, patients were categorized into a low e-value group (n=425) and a high e-value group (n=1 138). Data on gender, age, parental myopia history, and baseline measures such as spherical equivalent (SE), axial length, and corneal e-value were collected. Differences in axial length change and corneal fluorescein staining rates were compared between the two groups at 1 and 2 years after the start of lens wear. A generalized linear mixed model was established with axial length change as the dependent variable to analyze the correlation between axial length change and baseline corneal e-value. Results: The initial age of the 1 563 myopic patients was (10.84±2.13) years, with a baseline SE of (-3.05±1.30) D. After 1 year of lens wear, the axial length change was (0.20±0.19) mm in the low e-value group and (0.24±0.20) mm in the high e-value group. After 2 years, the changes were (0.38±0.25) mm and (0.43±0.27) mm, respectively, with statistically significant differences (all P<0.05). The incidence of corneal staining after 1 year of lens wear was 9.2% (39/425) in the low e-value group and 14.1% (160/1 138) in the high e-value group. After 2 years, the rates were 15.8% (67/425) and 21.8% (248/1 138), respectively, with statistically significant differences (all P<0.05). After adjusting for parental myopia history, age, SE, and baseline axial length, the baseline corneal e-value was positively correlated with axial length change at 1 and 2 years after lens wear (all P<0.05). Conclusions: Corneal e-value is an independent factor influencing the effectiveness of orthokeratology in controlling myopia. A smaller corneal e-value is associated with slower axial length growth after orthokeratology, indicating better control of myopia in treated eyes.

[The correlations of single photon emission computed tomography joints scan and bone metabolic markers in active rheumatoid arthritis].

Objective: To explore the correlation between quantitative value of joint bone scan by single photon emission computed tomography(SPECT) and serum bone metabolic markers in patients with active rheumatoid arthritis(RA). Method: Clinical data of 60 newly diagnosed RA patients were retrospectively collected in Department of Rheumatology and Immunology from May 2013 to December 2014, including 28 cases with medical history less than 6 months and 32 from 6 months to 2 years. Serum C-terminal telopeptide of type Ⅰ collgen(CTX-Ⅰ)and N-terminal propeptide of type Ⅰ collagen(PINP)were tested by chemiluminesence. SPECT whole body bone and target joint scan before treatment was done. Thirty-nine healthy subjects as control group received ultrasound, electrocardiogram, X-ray, and whole body bone imaging examination. Quantitative values of joint imaging were calculated for the statistical analysis. Result: Demographic data between RA group and control group were comparable (P>0.05), including sample, sex, age and BMI. The joint SPECT value, CTX-Ⅰ and PINP levels were all significantly higher than those of control group (P<0.01), which were 6.48±1.98 versus 3.73±1.16; (0.66±0.37) mg/L versus (0.58±0.21) mg/L; (46.35±28.15) mg/L versus (30.47±13.75) mg/L respectively. Joint SPECT values had positive correlations with serum CTX-Ⅰ levels in all RA patients, as well as PINP in patients with disease duration 6mon-2years. And the according correlation coefficients were 0.513, 0.495, 0.402(P<0.05). But SPECT value had no correlation with CTX-Ⅰ (P=0.081) in patients with disease duration less than 6 mon.The correlation coefficient was 0.336. Conclusion: SPECT imaging quantitative values were positively correlated with serum bone metabolic parameters. Thus SPECT imaging alone or combined with bone markers are helpful in diagnosing active RA.

Fabrication and characterization of elastomeric polyester/carbon nanotubes nanocomposites for biomedical application.

A novel biodegradable polymer elastomer nanocomposite composing of poly(1,8-octanediol-citrate) (POC) polymer matrix and carbon nanotubes (CNTs) additive was successfully fabricated and systematically investigated using Fourier transform infrared (FT-IR), X-ray diffractometer (XRD), differential scanning calorimetry (DSC), tensile test, incubation and cytotoxicity tests. It was found that the addition of CNTs in POC elastomer did not result in any noticeable change in its chemical structure and the amorphous state. However, the tensile strength and elongation at break were greatly improved by the addition of CNTs in POC polymer matrix. It revealed that the swelling ratio and percentage of weight loss of POC/CNTs nanocomposite were lower, compared with the pure POC material. Moreover, the adsorption amount of bovine serum albumin (BSA) increased with an increase of the CNTs mass content in POC matrix revealing the enhanced hydrophilicity of POC/CNTs nanocomposites contributed by the carboxyl of the CNTs. Additionally, the cytotoxicity tests with L929 cell line revealed that the experimental POC/CNTs nanocomposites possessed good in vitro biocompatibility.

Effects of electroacupuncture on the levels of retinal gamma-aminobutyric acid and its receptors in a guinea pig model of lens-induced myopia.

Gamma-aminobutyric acid (GABA) is a major inhibitory neurotransmitter of the retina and affects myopic development. Electroacupuncture (EA) is widely utilized to treat myopia in clinical settings. However, there are few reports on whether EA affects the level of retinal GABA during myopic development. To study this issue, in the present study, we explored the changes of retinal GABA content and the expression of its receptor subtypes, and the effects of EA stimulation on them in a guinea pig model with lens-induced myopia (LIM). Our results showed that the content of GABA and the expression of GABAA and GABAC receptors of retina were up-regulated during the development of myopia, and this up-regulation was inhibited by applying EA to Hegu (LI4) and Taiyang (EX-HN5) acupoints. Moreover, these effects of EA show a positional specificity. While applying EA at a sham acupoint, no apparent change of myopic retinal GABA and its receptor subtypes was observed. Taken together, our findings suggest that LIM is effective to up-regulate the level of retinal GABA, GABAA and GABAC receptors in guinea pigs and the effect may be inhibited by EA stimulation at LI4 and EX-HN5 acupoints.

Pregabalin alleviates the nitroglycerin-induced hyperalgesia in rats.

The association between the clinical use of nitroglycerin (NTG) and migraine suggests NTG as an animal model trigger for migraine. NTG-induced hyperalgesia in rats has been extensively used as a migraine model for pre-clinical research. Pregabalin is an anti-epileptic drug and may play a role in the preventive treatment of migraine; however, the mechanism of this action remains to be clarified. Herein, we performed the present study to investigate the effect of pregabalin on the NTG-induced hyperalgesia in rats. Sixty male Sprague-Dawley rats were divided equally into six groups. Thirty minutes before NTG injection, the rats were pretreated with pregabalin. von Frey hair testing was employed to evaluate tactile sensitivity. Enzyme-linked immunosorbent assay was used to analyze plasma calcitonin gene-related peptide (CGRP) levels in the jugular vein. Immunohistochemistry was applied to detect c-Fos-immunoreactive neurons and western blot was performed to detect c-Fos protein expression in trigeminal nucleus caudalis (TNC). We found that pregabalin pretreatment alleviated the NTG-induced hyperalgesia. Moreover, pregabalin suppressed peripheral CGRP release, c-Fos-immunoreactive neurons and the protein expression of c-Fos in TNC as well. These data suggest that pregabalin could alleviate the NTG-induced hyperalgesia. Further studies are required to determine the mechanisms of action for this effect.

A novel copper/polydimethiylsiloxane nanocomposite for copper-containing intrauterine contraceptive devices.

In this article, a novel composite of copper (Cu) nanoparticles and polydimethiylsiloxane (PDMS) has been prepared and investigated for the potential application in Cu-containing intrauterine device. The Cu/PDMS composite with various mass fraction of Cu nanoparticles was fabricated via the hot vulcanizing process. The chemical structures and surface morphologies of the Cu/PDMS composites were characterized confirming the physical interaction between Cu nanoparticles and PDMS. The surface morphology observation using scanning electron microscope and atomic force microscope showed the agglomeration of Cu nanoparticles in PDMS matrix and the distribution of the agglomerations was more uniform with increased amount of Cu nanoparticles. The cupric ion release behaviors of the Cu/PDMS composites with different amounts of Cu nanoparticles were investigated in simulated uterine fluid at 37°C for 150 days. The corrosion morphologies of the Cu/PDMS composites were also characterized. Both the burst release rate of the cupric ion in the first few days and the steady release rate after 30-day immersion were improved. The cytotoxicity test has been done for the Cu/PDMS composites.

Characterization of fiber texture by omega-scan x-ray diffraction.

On the basis of omega-scan x-ray diffraction (XRD), quantitative and qualitative characterization methods for fiber texture are proposed. The physical meaning of omega-scan curve is discussed in detail, and it is shown that the relative intensity curve of omega-scan XRD for a certain crystal plane is proportional to the pole density of the plane. Then qualitative and quantitative characterization methods for fiber texture are proposed from the concept of pole density. The proposed methods can be used in any crystal system. As an example for experimental verification, an orientation distribution function (ODF) experiment and a series of omega-scan XRD experiments are performed on a sputtered platinum film. From the comparison between the result of the ODF experiment and that of the analyses on the omega-scan XRD experiments, it is proved that the proposed qualitative and quantitative methods are effective and simple.