A Subtle Change in the Flexible Achiral Spacer Does Matter in Supramolecular Chirality: Two-Fold Odd-Even Effect in Polymer Assemblies.

Precise control over the chirality and morphologies of polymer assemblies, a remaining challenge for both chemists and materials scientists, is receiving ever-increasing attention in the recent years. Herein, we report the subtle manipulation of the achiral spacers from the chiral stereocenter to the azobenzene (Azo) unit, of which the chiroptical consistency or chiroptical inversion of self-assemblies could be successfully controlled and present "two-fold" odd-even effect. Furthermore, morphological transitions from 0D spherical micelles, 1D worms, and nanowires to 3D vesicles, spindle- and dumbbell-shaped vesicles were also unexpectedly found to exhibit odd-even correlations. These observations were collectively elucidated by mesomorphic properties, stacking modes, chiroptical dynamics, and stimuli-responsive behaviors. Negligible modifications to the spacer structures can enable remarkable modulation of supramolecular chirality and anisotropic topologies in polymer assemblies, which is of great significance for the design of complex chiral functional polymers.

VAR-tree model based spatio-temporal characterization and prediction of O3 concentration in China.

Ozone (O3) pollution in the atmosphere is getting worse in many cities. In order to improve the accuracy of O3 prediction and obtain the spatial distribution of O3 concentration over a continuous period of time, this paper proposes a VAR-XGBoost model based on Vector autoregression (VAR), Kriging method and XGBoost (Extreme Gradient Boosting). China is used as an example and its spatial distribution of O3 is simulated. In this paper, the O3 concentration data of the monitoring sites in China are obtained, and then a spatial prediction method of O3 mass concentration based on the VAR-XGBoost model is established, and finnally its influencing factors are analyzed. This paper concludes that O3 features the highest correlation with PM2.5 and the lowest correlation with SO2. Among the measurement factors, wind speed and temperature are the most important factors affecting O3 pollution, which are positively correlated to O3 pollution. In addition, precipitation is negatively correlated with 8-hour ozone concentration. In this paper, the performance of the VAR-XGBoost model is evaluated based on the ten-fold cross-validation method of sample, site and time, and a comparison with the results of XGBoost, CatBoost (categorical boosting), ExtraTrees, GBDT (gradient boosting decision tree), AdaBoost (adaptive boosting), RF (random forest), Decision tree, and LightGBM (light gradient boosting machine) models is conducted. The result shows that the prediction accuracy of the VAR-XGBoost model is better than other models. The seasonal and annual average R2 reaches 0.94 (spring), 0.93 (summer), 0.92 (autumn), 0.93 (winter), and 0.95 (average from 2016 to 2021). The data show that the applicability of the VAR-XGBoost model in simulating the spatial distribution of O3 concentrations in China performs well. The spatial distribution of O3 concentrations in the Chinese region shows an obvious feature of high in the east and low in the west, and the spatial distribution is strongly influenced by topographical factors. The mean concentration is clearly low in winter and high in summer within a season. The results of this study can provide a scientific basis for the prevention and control of regional O3 pollution in China, and can also provide new ideas for the acquisition of data on the spatial distribution of O3 concentrations within cities.

Cost-effectiveness of camrelizumab plus chemotherapy vs. chemotherapy in the first-line treatment of non-squamous NSCLC: Evidence from China.

Objective: We aimed to evaluate the cost-effectiveness of camrelizumab plus chemotherapy compared with chemotherapy alone as the first-line treatment for patients with metastatic or advanced non-squamous non-small cell lung cancer (NSCLC) without targetable epidermal growth factor receptor or anaplastic lymphoma kinase genetic aberrations in patients in China. Methods: A partitioned survival model was constructed to estimate the cost-effectiveness of camrelizumab plus chemotherapy vs. chemotherapy in the first-line treatment of non-squamous NSCLC from a Chinese healthcare perspective. Survival analysis was performed to calculate the proportion of patients in each state using data from trial NCT03134872. The cost of drugs was obtained from Menet, and the cost of disease management was obtained from local hospitals. Health state data were obtained from published literature. Both deterministic sensitivity analyses (DSA) and probabilistic sensitivity analysis (PSA) were adopted to verify the robustness of the results. Results: Compared with chemotherapy alone, camrelizumab plus chemotherapy provided 0.41 incremental quality-adjusted life years (QALYs) at an incremental cost of $10,482.12. Therefore, the incremental cost-effectiveness ratio of camrelizumab plus chemotherapy was $25,375.96/QALY from the Chinese healthcare perspective, much lower than three times the GDP per capita of China in 2021 ($35,936.09) as the willingness-to-pay threshold. The DSA indicated that the incremental cost-effectiveness ratio was most sensitive to the utility value of progression-free survival, followed by the cost of camrelizumab. The PSA illustrated that camrelizumab had 80% probability of being cost-effective at the threshold of $35,936.09 per QALY gained. Conclusion: The results suggest that camrelizumab plus chemotherapy is a cost-effective choice in the first-line treatment for patients with non-squamous NSCLC in China. Although this study has limitations such as short time of use of camrelizumab, no adjustment of Kaplan-Meier curves and the median overall survival that has not been reached, the difference in results caused by these factors is relatively small.

PHF8 promotes osteogenic differentiation of BMSCs in old rat with osteoporosis by regulating Wnt/ß-catenin pathway.

Osteoporosis is a progressive bone disorder with a higher incidence in the elderly and has become a major public health concern all over the world. Therefore, it is urgent to investigate the mechanisms underlying the pathogenesis of osteoporosis. In this study, the osteoporosis animal model was established, and then rat bone marrow mesenchymal stem cells (rBMSCs) were cultured. The results showed that PHF8 expression was decreased in osteoporosis rats compared to controls. Overexpression of PHF8 promoted BMSC osteogenic differentiation and the expression of osteogenesis-related genes. In addition, the Wnt/ß-catenin signaling pathway in BMSCs was inhibited in osteoporosis rats, which was rescued by overexpression of PHF8. After treatment with the Wnt pathway antagonist, the improved osteogenic differentiation of BMSCs induced by overexpression of PHF8 was blocked. Collectively, our data revealed that the decreased expression of PHF8 in osteoporosis rats suppressed the osteogenic differentiation of BMSCs, which was then restored by PHF8 overexpression. Furthermore, the inhibition of the Wnt/ß-catenin signaling pathway in BMSCs suppressed osteogenic differentiation. Thus, these findings indicated that PHF8 plays a role in osteogenic differentiation through the Wnt/ß-catenin signaling pathway.

Effect of the combined application of orthokeratology and single-vision spectacles on slowing the progression of high myopia: A systematic review and meta-analysis.

PURPOSE: The purpose of the study was to conduct a meta-analysis about the effect of the combined application of orthokeratology and single-vision spectacles on slowing the progression of high myopia. METHODS: The literature was searched in PubMed, EMBASE, the Cochrane Library, Wang Fang Data, CNKI and sinoMed. The Cochrane Handbook was used to evaluate the quality of the included randomized clinical trials, and the Newcastle-Ottawa Scale was used to evaluate the included case-control or cohort studies. The results were analyzed by Revman 5.3. RESULTS: Five studies (2 randomized clinical trials, 2 case-controls, and 1 cohort study) with a total of 360 patients were included in this meta-analysis. The follow-up time was at least 1 year. Combined application of orthokeratology and single-vision spectacles were used in the experimental group. The control group used single-vision spectacles only. The pooled estimates indicated that the standardized mean difference between the 2 groups was -1.46 mm (95% confidence interval: -1.88 to -1.05; P < .05) for axial length elongation and -1.85D (95% confidence interval: -2.40 to -1.31; P < .05) for change in spherical equivalent refraction. No serious adverse events were reported in all studies. CONCLUSION: The combined application of orthokeratology and single-vision spectacles is more effective than single-vision spectacles only on slowing the progression of high myopia.

Spatio-Temporal Characteristics of PM2.5 Concentrations in China Based on Multiple Sources of Data and LUR-GBM during 2016-2021.

Fine particulate matter (PM2.5) has a continuing impact on the environment, climate change and human health. In order to improve the accuracy of PM2.5 estimation and obtain a continuous spatial distribution of PM2.5 concentration, this paper proposes a LUR-GBM model based on land-use regression (LUR), the Kriging method and LightGBM (light gradient boosting machine). Firstly, this study modelled the spatial distribution of PM2.5 in the Chinese region by obtaining PM2.5 concentration data from monitoring stations in the Chinese study region and established a PM2.5 mass concentration estimation method based on the LUR-GBM model by combining data on land use type, meteorology, topography, vegetation index, population density, traffic and pollution sources. Secondly, the performance of the LUR-GBM model was evaluated by a ten-fold cross-validation method based on samples, stations and time. Finally, the results of the model proposed in this paper are compared with those of the back propagation neural network (BPNN), deep neural network (DNN), random forest (RF), XGBoost and LightGBM models. The results show that the prediction accuracy of the LUR-GBM model is better than other models, with the R2 of the model reaching 0.964 (spring), 0.91 (summer), 0.967 (autumn), 0.98 (winter) and 0.976 (average for 2016-2021) for each season and annual average, respectively. It can be seen that the LUR-GBM model has good applicability in simulating the spatial distribution of PM2.5 concentrations in China. The spatial distribution of PM2.5 concentrations in the Chinese region shows a clear characteristic of high in the east and low in the west, and the spatial distribution is strongly influenced by topographical factors. The seasonal variation in mean concentration values is marked by low summer and high winter values. The results of this study can provide a scientific basis for the prevention and control of regional PM2.5 pollution in China and can also provide new ideas for the acquisition of data on the spatial distribution of PM2.5 concentrations within cities.

Photo-aging evaluation - In vitro biological endpoints combined with collagen density assessment with multi-photon microscopy.

BACKGROUND: Ultraviolet exposure has profound effect on the dermal connective tissue of human skin. OBJECTIVE: We aimed to develop and validate an evaluation method/methodology using a full-thickness reconstructed skin model, to assess the anti-photoaging efficacy of cosmetic ingredients and sunscreen formulas by blending multi relevant biological endpoints including the newly developed dermal collagen quantification method with Multi-photon microscopy. METHODS: The response of ex vivo human skin to UVA exposure was first characterized with multiphoton microscopy. Reconstructed full-thickness skin models was then used to reproduce the data and to create a proof-of-concept study by treating the models with sunscreen prototypes A or B, which differ on their UVA absorption properties, and systemic Vitamin C (Vit C). After exposure to UVA, the collagen density was quantified via multiphoton microscopy with automatic imaging processing. Histology, fibroblasts number, metalloprotease 1 (MMP1) secretion were also assessed. RESULTS: UVA exposure induced pronounced reduction in collagen density and increased MMP1 secretion within both ex vivo human skin and reconstructed skin. Histological damage and fibroblast disappearance was observed with reconstructed skin. Within the proof-of-concept study prototype B, possessing higher UVA filtration, gave better protection than prototype A on the UV associated biological markers, and association with Vit C boosted sunscreen formula efficacy. CONCLUSIONS: The photoaging evaluation method, consists of multi biological markers as well as dermal collagen quantification, is a relevant mean to assess the pre-clinical efficacy of anti-photoaging ingredients and sunscreen products. This approach is also beneficial for evaluating the efficacy of sunscreens and photoprotective ingredients.

Effects of bariatric surgery on serum uric acid in people with obesity with or without hyperuricaemia and gout: a retrospective analysis.

OBJECTIVES: Weight reduction may reduce serum uric acid (SUA). This study aimed to examine the changes of SUA before and after bariatric surgery in patients with obesity with or without hyperuricaemia and gout. METHODS: This is a retrospective analysis of 147 routinely collected data on hospital patients with obesity who underwent bariatric surgery. The body weight and SUA were measured at baseline and after surgery at 1-7 days, 1, 3, 6 and 12 months. RESULTS: The mean (95% CI) weight reduction of 147 patients was 30.7 (28.7, 32.7) kg 1 year after surgery (P < 0.001). SUA decreased rapidly from 419.0 (400.1, 437.8) µmol/l at baseline to 308.4 (289.6, 327.2) µmol/l at 1-7 days, flared up to 444.8 (423.9, 465.6) µmol/l at 1 month, then decreased again to 383.8 (361.5, 406.1) µmol/l at 3 months, 348.9 (326.3, 371.5) µmol/l at 6 months and 327.9 (305.3, 350.5) µmol/l at 12 months (P < 0.001). Similar trends but more rapid reductions were observed in 55 hyperuricaemia patients and 25 gout patients. All 25 gout patients had an elevated SUA above the therapeutic target (≥360µmmol/l) at baseline, but in 10 patients it was reduced below this target at 12 months. The mean reduction (95% CI) of SUA in all patients and gout patients was 84.3 (63.1-105.4) and 163.6 (103.9, 223.3) µmmol/l, respectively. CONCLUSION: Bariatric surgery significantly reduces body weight and SUA for obese patients with hyperuricaemia and gout. Gout may be considered as an indicator for this surgical treatment in people with severe obesity.

Efficacy and safety of atropine to control myopia progression: a systematic review and meta-analysis.

BACKGROUND: The effect and safety of atropine on delaying the progression of myopia has been extensively studied, but its optimal dose is still unclear. Therefore, the purpose of this meta-analysis is to systematically evaluate the safety and effectiveness of atropine in controlling the progression of myopia, and to explore the relationship between the dose of atropine and the effectiveness of controlling the progression of myopia. METHODS: This work was done through the data searched from PubMed, MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials. The Cochrane Handbook was also used to evaluate the quality of the included studies. In addition, a meta-analysis was performed using Revman5.3 software. RESULTS: A total of 10 randomized controlled trials (RCTs) were included. Myopia progression was mitigated greater in the atropine treatment group than that in the control group, with MD = - 0.80, 95% CI (- 0.94, - 0.66) during the whole observation period. There was a statistical difference among 0.05, 0.5, and 1.0% atropine (P = 0.004). In addition, less axial elongation was shown, with MD = - 0.26, 95% CI (- 0.33, - 0.18) during the whole observation period. CONCLUSION: The effectiveness of atropine in controlling the progression of myopia was dose related. A 0.05% atropine was likely to be the optimal dose.

Analysis of patterns and risk factors regarding the onset of nodules in the contralateral thyroid lobe during follow-up ultrasonography among patients after unilateral lobectomy for the treatment of papillary thyroid carcinoma.

BACKGROUND: This study tries to find the patterns of new nodules in contralateral thyroid lobe among papillary thyroid carcinomas (PTCs) after lobectomy using ultrasonography. METHODS: Of note, 456 PTCs were enrolled. Clinicopathological features of primary tumors and sonographic patterns of new nodules in contralateral lobe were documented. Logistic regression analysis was performed to identify risk factors for new nodules. RESULTS: The overall incidence of new nodules was 41.9%. 96.3% of new nodules were no greater than 1 cm while only 10.5% of those were with high suspicion of malignancy. There was no difference in the incidence and sonographic patterns of new nodules between patients with an original tumor size <1 cm (n = 267) vs 1 to 4 cm (n = 189). Multivariate logistic regression analysis showed age (OR, 1.021; 95% CI, 1.001-1.041; P = .036) played risk factor for new nodules while tumor size >1 cm did not. CONCLUSION: New nodules in the contralateral lobe were common, but usually small and benign by ultrasound features. Older age was found to be a risk factor to predict new nodules. This study supports lobectomy for 1-4 cm PTC in terms of incidence of new nodules on the remnant lobe.

Clinical characteristics and surgical outcomes of acute acquired Comitant Esotropia.

BACKGROUND: To describe the clinical characteristics and the outcomes of strabismus surgery for acute acquired comitant esotropia (AACE). METHODS: Medical records of 45 AACE patients were retrospectively analyzed. The insertion location of medial rectus was compared between the AACE patients and comitant exotropic patients. The location was also compared with those measured in other studies. Surgical outcome measurements included amount of deviation and level of binocularity at last follow-up. RESULTS: The distance from medial rectus to limbus was shorter in AACE patients than in patients with comitant exotropia. The distance was also shorter in AACE patients than patients in other studies. Out of the 45 patients, 2 had neurological diseases. Neostigmine test was negative in all patients. The age at onset of AACE was 5-47 years (mean 19.1 ± 7.3 years), one patient was 5 years (2.2%), 20 patients were 11-17 years (44.5%) and the other 24 patients were 18-47 years old (53.3%). The mean cycloplegic refraction was - 4.1 ± 3.0 diopters (D) and 41 patients were myopic (91%). The angle of deviation was 40.5 ± 19.5 prism diopters (PD) at distance and 35.6 ± 19.9PD at near preoperatively. The angle was 0.8 ± 1.6 PD at distance and 0.7 ± 1.8 PD at near postoperatively. Diplopia resolved in patients who underwent strabismus surgery, with no recurrence during the follow-up period. Thirty patients had stereopsis postoperatively. CONCLUSIONS: AACE seems to occur mostly in older children and adults and myopes. The distance from the insertion to limbus of medial rectus was shorter in patients with AACE. Good results can be achieved by strabismus surgery.

In situ grown Ni phosphide nanowire array on Ni foam as a high-performance catalyst for hydrazine electrooxidation.

Synthesis of high-performance and cost-effective electrocatalysts towards hydrazine electrooxidation is vital to develop the direct hydrazine fuel cell (DHFC) as a viable energy conversion technology. Herein, we report a combined experimental and theoretical study of nickel phosphides (NixP) as promising catalysts for hydrazine electrooxidation. NixP nanowire array supported on a Ni foam (NF) was synthesized by a one-step phosphorization method using hypophosphite as a P-source. Ni12P5 and Ni2P phases are observed as the products of the direct phosphorization of commercial NF under the applied conditions with Ni2P nanoparticles exclusively distributing on the surface of Ni12P5. The NixP/NF catalyst exhibits a synergetic capabilities of exceptionally high activity, excellent durability and nearly 100% selectivity towards the complete electrooxidation of hydrazine in alkaline condition, which is among the best performance reported on hydrazine electrooxidation catalysts. First-principles calculations have been conducted to gain insight into the catalytic mechanism of Ni phosphides towards hydrazine electrooxidation.

Tuning the Surface Composition of Ni/meso-CeO2 with Iridium as an Efficient Catalyst for Hydrogen Generation from Hydrous Hydrazine.

Selective decomposition of hydrous hydrazine (N2 H4 ⋅H2 O) over metal catalysts provides a promising means for onboard or portable hydrogen source applications. Studies on N2 H4 ⋅H2 O decomposition catalysts mainly focus on the effects of bulk composition and structure on their performances, instead of the surface-composition-dependent properties. Herein, the synthesis of an Ir-modified Ni/meso-CeO2 catalyst is reported by using a combination of colloidal solution combustion synthesis and galvanic replacement methods. A combination of structural characterization, control experiments, and DFT calculations reveals that the Ni-Ir alloy resulting from calcination treatment exerts a profound effect on the catalytic properties. The resulting Ni@Ni-Ir/meso-CeO2 catalyst shows excellent catalytic performance towards hydrogen generation from N2 H4 ⋅H2 O, which compares favorably with the Ni-Ir bimetallic catalysts reported to date.

Evaluation of the ocular surface in the patients after strabismus surgery / 国际眼科杂志(Guoji Yanke Zazhi)

·AIM:To evaluate the ocular surface in the patients after strabismus surgery. ·METHODS: One hundred and eighty-eight hospitalized patients (240 eyes) with strabismus from May 2015 to October 2016 in Aier Hospital were divided into 3 groups according to the type of incision:85 cases(100 eyes) with the corneal limbus incision in Group A;35 cases(50 eyes) with the cross-muscle incision in Group B; 68 cases (90 eyes) with the adjacent-fornix incision (including Parks incisions and improved Parks incisions) in Group C. And 75 eyes with single extraoeular muscle surgery, 110 eyes with 2 extraoeular muscle surgery, 55 cases with 3 extraoeular muscle surgery. The first noninvasive tear film break-up time (NITBUTf) and the tear meniscus height (TMH) were tested by Oculus anterior segment analyzer preoperatively and 1d, 1, 2 and 4wk postoperatively. The data were studied by statistics. · RESULTS: Comparing with preoperative, TMH increased significantly at post-operatively 1d in all group, NIKBUTf reduced significantly(P<0.05). NIKBUTf was recovered in Group A at post-operative 2wk. NIKBUTf were recovered in Group B and C at post-operative 1wk. TMH were recovered in Group A and B at post-operative 2wk. TMH was recovered in Group C at post-operative 1wk. NIKBUTf and TMH were recovered with the single extraoeular muscle surgery at post-operative 1wk. They were recovered at post-operative 2wk with the 2 and 3 extraoeular muscle surgery. ·CONCLUSION: Surgical incision and surgical muscle number may affect the ocular surface of the people after strabismus surgery. The adjacent fornix conjunctival incision has less effect. The less number of muscles in strabismus surgery,the less effect on ocular surface.

Development of Novel Nrf2/ARE Inducers Bearing Pyrazino[2,1-a]isoquinolin Scaffold with Potent In Vitro Efficacy and Enhanced Physicochemical Properties.

Pyrazino[2,1-a]isoquinolin analogues were reported as potent activators of Nrf2/ARE signaling both in vitro and in vivo by our group. In this study, we simplified the ring system to investigate the functions of various parts of the pyrazino[2,1-a]isoquinolin scaffold. We proved that the tetrahydroisoquinoline was not essential for activity and the pyrido[1,2-a]pyrazin analogues 3b and 3g retained the cellular Nrf2/ARE activation activity. Besides, this simplification significantly enhanced water solubility and membrane permeability, indicating that these compounds are more favourable for the further development of therapeutic agents around Nrf2 activation.

Complete and Rapid Conversion of Hydrazine Monohydrate to Hydrogen over Supported Ni-Pt Nanoparticles on Mesoporous Ceria for Chemical Hydrogen Storage.

The development of active, selective, and robust catalysts is a key issue in promoting the practical application of hydrazine monohydrate (N2 H4 ⋅H2 O) as a viable hydrogen carrier. Herein, the synthesis of a supported Ni-Pt bimetallic nanocatalyst on mesoporous ceria by a one-pot evaporation-induced self-assembly method is reported. The catalyst exhibits exceptionally high catalytic activity, 100 % selectivity, and satisfactory stability in promoting H2 generation from an alkaline solution of N2 H4 ⋅H2 O at moderate temperatures. For example, the Ni60 Pt40 /CeO2 catalyst enabled complete decomposition of N2 H4 ⋅H2 O to generate H2 at a rate of 293 h(-1) at 30 °C in the presence of 2 M NaOH, which compares favorably with the reported N2 H4 ⋅H2 O decomposition catalysts. Phase/structural analysis by XRD, TEM, and Auger electron spectroscopy was conducted to gain insight into the excellent catalytic performance of the Ni-Pt/CeO2 catalyst.

Hyperopic corneal refractive surgery in patients with accommodative esotropia and amblyopia.

PURPOSE: To explore whether hyperopic excimer corneal refractive surgery can affect ocular alignment and stereopsis in patients with both accommodative esotropia and amblyopia. METHODS: In this prospective study, 26 eyes of 13 patients with accommodative esotropia and amblyopia underwent bilateral hyperopic corneal refractive surgery: 9 patients underwent laser in situ keratomileusis (LASIK); 4, laser epithelial keratomileusis (LASEK). The main ocular examinations included pre- and postoperative best-corrected and uncorrected visual acuity, refractive error, ocular alignment, and stereopsis. RESULTS: Preoperative cycloplegic refraction in the right eyes was +5.64 ± 2.09 D; in the left eyes, +5.91 ± 1.97 D. After surgery, refraction in the right eyes was +1.13 ± 1.21 D; in the left eyes, +1.44 ±1.53 D. The mean logMAR uncorrected visual acuity was 0.46 ± 0.30 before surgery and 0.32 ± 0.25 after surgery (t = 5.72, P = 0.001). The mean pre- and postoperative best-corrected visual acuity were 0.31 ± 0.28 and 0.29 ± 0.25, respectively; there was no significant difference between the two groups (t = 1.23, P = 0.22). The average uncorrected esotropia was 37.92(Δ) ± 9.12(Δ) before surgery and 2.76(Δ) ± 2.80(Δ) after (P < 0.001). Using a synoptophore, 2 patients (15.3%) had preoperative stereopsis and 11 patients (84.6%) had postoperative stereopsis. No patients experienced lower stereopsis postoperatively. CONCLUSIONS: In this cohort, hyperopic corneal refractive surgery can improve the alignment, uncorrected visual acuity, and stereopsis in patients with accommodative esotropia and amblyopia.

[Effects of androgen on microstructure and mechanics nature of bone in orchiechtomied male rats].

OBJECTIVE: To investigate the effect of androgen on microstructure and mechanics nature of bone in orchiechtomied (ORX) male rats and reveal its mechanism by using the Micro CT analysis, bone biomechanics test, bone histomorphometric parameter test, and total body bone mineral density (BMD) measured by dual-energy X-ray absorptiomery (DXA). METHODS: Thirty 12-month-old male Wister rats were randomly divided into three groups including ORX, sham-operated (Sham) and androgen (AD) group, ten rats in every group. Total body BMD was measured by DXA. Femurs and vertebrae were then harvested at the 12 th week after ORX for micro-computed tomography (Micro CT), histology and biomechanical were tested. RESULTS: The administration of testosterone may reverse the decreasing BMD of total body and may prevent the decreasing weight. The biomechanical values of Maximum load, Enery, Maximum stress, Elastic Modulus of AD group significantly enhanced compared with ORX group (P < 0.05). The results of histomorphometric parameters showed that cancellous bone volume, osteoblast-osteoid interface, linear extent of bone formation, mineralizing surfaces, mineral apposition rate increased in the therapy group. CONCLUSION: Androgen can accelerate cancellous bone formation and bone turnover, improve bone microstructure and enhance bone intensity and BMD.