The growth and nutrient removal properties of heterotrophic microalgae Chlorella sorokiniana in simulated wastewater containing volatile fatty acids.

To reduce the high cost of organic carbon sources in waste resource utilization in the cultivation of microalgae, volatile fatty acids (VFAs) derived from activated sludge were used as the sole carbon source to culture Chlorella sorokiniana under the heterotrophic cultivation. The addition of VFAs in the heterotrophic condition enhanced the total nitrogen (TN) and phosphorus (TP) removal of C. sorokiniana, which proved the advantageous microalgae in using VFAs in the heterotrophic culture after screening in the previous study. To discover the possible mechanism of nitrogen and phosphorus adsorption in heterotrophic conditions by microalgae, the effect of different ratios of VFAs (acetic acid (AA): propionic acid (PA): butyric acid (BA)) on the nutrient removal and growth properties of C. sorokiniana was studied. In the 8:1:1 group, the highest efficiency (77.19%) of VFAs assimilation, the highest biomass (0.80 g L-1) and lipid content (31.35%) were achieved, with the highest TN and TP removal efficiencies of 97.44 % and 91.02 %, respectively. Moreover, an aerobic denitrifying bacterium, Pseudomonas, was determined to be the dominant genus under this heterotrophic condition. This suggested that besides nitrate uptake and utilization by C. sorokiniana under the heterotrophy, the conduct of the denitrification process was also the main reason for obtaining high nitrogen removal efficiency.

Effects of thumb-tack needling combined with sporting on older adult patients with knee osteoarthritis: A randomized active-control clinical trial.

AIM: The aim of this clinical study was to explore the effects of thumb-tack needling combined with sporting (TTNS) therapy on the improvement of pain and joint function in older adult patients with knee osteoarthritis (KOA). METHODS: A total of 120 older adult patients with KOA were randomly assigned to receive TTNS therapy or medicine treatment (Med group) only for 1 month. The patients were followed up for 3 months and clinical efficacies were evaluated using a visual analog scale to assess pain, the Lequesne scoring system to assess motor function, and the Western Ontario and McMaster University Osteoarthritis Index to assess KOA severity. Blood was collected to measure the levels of interleukin-6 and tumor necrotic factor-alpha using enzyme-linked immunosorbent assay. RESULTS: The data suggested that TTNS therapy resulted in a significantly higher clinical efficacy (P = 0.012). Visual analog scale score, Lequesne index, and Western Ontario and McMaster University Osteoarthritis Index of the TTNS group at the time of post-treatment (1 month) and post-follow-up (3 months) were also lower compared with the Med group. Patients in the TTNS group also showed lower levels of serum tumor necrotic factor-alpha and interleukin-6. CONCLUSIONS: TTNS therapy is more efficacious than pharmacological treatment in improving the clinical outcomes of patients with KOA, which suggests its clinical utility in the management of KOA. Geriatr Gerontol Int 2024; 24: 415-420.

Multi-field-driven optomechanical entanglement.

Cavity optomechanical (COM) entanglement, playing an essential role in building quantum networks and enhancing quantum sensors, is usually weak and easily destroyed by noises. As feasible and effective ways to overcome this obstacle, optical or mechanical parametric modulations have been used to improve the quality of quantum squeezing or entanglement in various COM systems. However, the possibility of combining these powerful means to enhance COM entanglement has yet to be explored. Here, we fill this gap by studying a COM system containing an intra-cavity optical parametric amplifier (OPA), driven optically and mechanically. By tuning the relative strength and the frequency mismatch of optical and mechanical driving fields, we find that constructive interference can emerge and significantly improve the strength of COM entanglement and its robustness to thermal noises. This work sheds what we believe to be a new light on preparing and protecting quantum states with multi-field driven COM systems for diverse applications.

Study on Correction Method of Counting Loss below the Threshold for Low Energy Radionuclides Based on Monte Carlo Simulation.

ABSTRACT: In the absolute measurement method of nuclide radioactivity by the internal gas proportional counter, the reasonable correction of the small pulse counting loss is the key to obtaining the measurement results accurately. Considering the decay type and energy of radioactive gas nuclides, the influence of the low-energy beta particles and the wall effect counting loss on the activity measurement results is different also. To this end, two typical radioactive gas nuclides ( 37 Ar and 3 H) are used to study the cause of counting loss based on the Monte Carlo simulation. The results show that the counting loss of small pulse in the activity measurement of 37 Ar comes mainly from the wall effect generated by x rays. Within the given gas pressure of 60-300 kPa, the simulated wall effect correction factors are 1.063-1.021. The decay energy of ß particles generated by 3 H is very low, and there is no obvious wall effect. The small pulse counting loss mainly comes from the low-energy beta particles' contribution with the energy below the counting threshold, which can be corrected by extrapolating the beta energy spectrum at a lower counting threshold (below 1 keV).

The effects of carbon nitrogen ratio and salinity on the treatment of swine digestion effluent simultaneously producing bioenergy by microalgae biofilm.

In order to remove high concentrations of ammonia nitrogen (NH4+-N) and refractory sulfamethazine (SM2) from swine digestion effluent, different carbon/nitrogen (C/N) ratios and salinity were used to determine the effects of pollutants removal in the microalgae biofilm system. Microalgae biofilm treatment under optimal environmental conditions in synthetic swine digestion effluent were C/N ratio of 20 and salinity of 140 mM. In order to make the actual swine digestion effluent discharge up to the standard, three different two-cycle treatments (suspended microalgae, microalgae biofilm, microalgae biofilm under the optimal conditions) were studied. The results showed that after two-cycle treatment with microalgae biofilm under the optimal conditions, the actual swine digestion effluent levels of total nitrogen (TN), NH4+-N, total phosphorus (TP), chemical oxygen demand (COD), SM2 were 22.65, 9.32, 4.11, 367.28, and 0.99 mg L-1, respectively, which could satisfy the discharge standards for livestock and poultry wastewater in China. At the same time, first-order kinetic simulation equations suggested a degradation half-life of 4.85 d for SM2 under optimal conditions in microalgae biofilm, and microbial community analysis indicated that the dominant genus was Halomonas. Furthermore, 35.66% of lipid, 32.56% of protein and 18.44% of polysaccharides were harvested after two-cycle in microalgae biofilm treatment under optimal environmental conditions. These results indicated that the regulation of C/N and salinity in microalgae biofilm for the treatment of swine digestion effluent was a high-efficiency strategy to simultaneously achieve wastewater treatment and bioenergy production.

Inhibition of VDAC1 prevents oxidative stress and apoptosis induced by bisphenol A in spermatogonia via AMPK/mTOR signaling pathway.

Bisphenol A (BPA), one of the main components of industrial products, is clinically associated with the increased male infertility rate. However, the underlying molecular mechanism of the BPA-resulted reproductive toxicity is not fully elucidated. Voltage-dependent anion channel 1 (VDAC1) is a pore protein and located at the outer mitochondrial membrane. As a mitochondrial gatekeeper, VDAC1 controls the release of reactive oxygen species (ROS) and the metabolic and energetic functions of mitochondria, and serves as a critical player in mitochondrial-mediated apoptosis. Herein, we explored the role of VDAC1 in BPA-induced apoptosis of spermatogonia. The results showed that BPA increased spermatogonia cell line GC-1 spg cell apoptosis and intracellular ROS level, and suppressed AMPK/mTOR signaling pathway at a dose of 80 µM for 48 hr. Lentivirus-mediated short hairpin RNA targeting VDAC1 (Lv-shVDAC1) silenced VDAC1 expression and enhanced BPA-restricted cell viability. Knockdown of VDAC1 inhibited the apoptosis of BPA-treated GC-1 spg cells determined by with changes of the expressions of pro-apoptotic and anti-apoptotic proteins. Knockdown of VDAC1 also alleviated the BPA-triggered intracellular ROS generation and oxidative stress. Moreover, silence of VDAC1 increased AMPKα1/2 phosphorylation and suppressed mTOR phosphorylation under BPA exposure. Dorsomorphin, an AMPK inhibitor, partially abolished the effects of VDAC1 gene silencing on BPA-stimulated GC-1 spg cells. In conclusion, inhibition of VDAC1 attenuated the BPA-induced oxidative stress and apoptosis and promoted the cell viability in spermatogonia through modulating AMPK/mTOR signaling pathway.

The growth and lipid accumulation of Scenedesmus quadricauda under nitrogen starvation stress during xylose mixotrophic/heterotrophic cultivation.

In order to conquer the block of high cost and low yields which limit to realize the commercialization of microalgal biodiesel, the mixotrophic and heterotrophic cultivation of Scenedesmus quadricauda FACHB-1297 fed on xylose was separately studied employing six forms of media: phosphorus sufficient, phosphorus restricted, and phosphorus starvation were combined with nitrogen sufficient and nitrogen starvation conditions. The maximum lipid content (about 41% of dry weight) was obtained on the 5th day (heterotrophic cultivation) and 8th day (mixotrophic cultivation) under the nitrogen starved and phosphorus sufficient (N0&P) conditions, which was about twofold in comparison to the final lipid content on the sufficient nitrogen condition (control). Under mixotrophic and heterotrophic modes, the highest lipid production was achieved in the N0&P trial, with the value of 274.96 mg/L and 193.77 mg/L, respectively. Xylose utilization rate of 30-96% under heterotrophic modes was apparently higher than that of 20-50% in mixotrophic modes. In contrast, phosphorus uptake rate of 100% under mixotrophic cultivation was significantly more than that of 60-90% in heterotrophic cultivation. Furthermore, under the condition of heterotrophic cultivation using xylose as a carbon source, the phosphorus had a positive impact on microalgae cell synthesis and the lipid content enhanced with the augmentation in phosphorus concentrations. We suggested that sufficient phosphorus should be supplied for obtaining higher microalgal lipid production in the lack of nitrogen under xylose heterotrophic/mixotrophic condition. This was a highly effective way to obtain efficient microalgae lipid production.

"We buy what we wanna be": Understanding the effect of brand identity driven by consumer perceived value in the luxury sector.

Prior studies focused on consumer satisfaction and loyalty have brought undeniable benefits to luxury brand marketing but are not sufficient to ensure a long-lasting and profitable customer-brand relationship in the new setting. Brand identity provides a valuable exploration of this issue. However, the current measurement of brand identity is relatively simple, and there is no clear answer to what factors encourage brand identity development. This study attempts to address this gap by dividing the brand identity structure from a multi-dimensional perspective, considering the role of luxury consumer perceived value and brand information quality in shaping the brand identity. Data was gathered by an online questionnaire survey from Chinese consumers who had purchased luxury jewelry, employing regression methods for analysis. The results show that four predictors representing luxury consumer perceived value all have a significant impact on the brand's social identity and personal identity. In addition, brand information quality also positively moderates the relationship between the luxury consumer perceived value and the brand's social identity. This study opens new horizons for considering dimensions other than the satisfaction or intention to use, expanding the applications of brand identity in a new context. The results contribute to increasing the awareness level of brand identity for luxury brand practitioners and offering them a new method of market strategy.

Enhancement of nutrients removal and biomass accumulation of algal-bacterial symbiosis system by optimizing the concentration and type of carbon source in the treatment of swine digestion effluent.

The algae-bacteria symbiosis system (ABS) is used to effectively solve the problems of low carbon/nitrogen (C/N) ratio, low biodegradability and high ammonia toxicity in swine digestion effluent. This study examined the effects of the concentration and type of carbon source on ABS in the pollutants removal especially ammonia. When C/N ratio was 30:1 and carbon source was sodium acetate, the ABS was most conducive to the removal of nitrogen, phosphorus and COD, and to the accumulation of biomass and lipids. To make the wastewater discharge meet the relevant standard, the ABS + mono-cultivation of algae reprocessing system (MAS), was applied to actual swine digestion effluent. Through adjusting the C/N ratio in ABS to 30:1, the biomass concentration was 2.06 times higher than that of raw wastewater, and the removal efficiencies of NH4+-N, TN, TP and COD increased by 1.43, 1.46, 1.95 and 1.28 times, respectively. The final concentrations of NH4+-N, TN, TP and COD after the treatment of ABS (C/N ratio of 30:1) + MAS, were 16.98 ± 1.07 mg L-1, 18.72 ± 1.81 mg L-1, 0.48 ± 0.01 mg L-1 and 263.49 ± 11.89 mg L-1, respectively, reached the Chinese discharge standards for livestock and poultry wastewater. Bacterial community analysis showed that the dominant species of the ABS (C/N ratio of 30:1) was Corynebacterium (genus level). This study revealed that adjusting the concentration and type of carbon source was helpful to the nutrient cycling and resource utilization of ABS, indicating a feasible technique for treating high ammonia nitrogen digestate.

Screening of the heterotrophic microalgae strain for the reclamation of acid producing wastewater.

For the sustainable development of the environment, to reduce the high cost and low productivity of microalgae biofuel, nine microalgae strains were screened to study the growh and nutrient removal properties under heterotrophic culture by using the waste carbon source of volatile fatty acids (VFAs). Chlorella sorokiniana (C.sorokiniana) was selected as the best strain with the highest biomass concentration of 0.77 g L-1, specific growth rate of 0.25 d-1, biomass productivity of 91.43 mg L-1 d-1, total nitrogen removal efficiency of 95.96% and total phosphorus removal efficiency of 93.42%. To study the utilization potential of acid-producing wastewater by heterotrophic microalgae, actual acid-producing wastewater was recycled three times for the utilization of C.sorokiniana. After the three utilization cultivation, the removal rates of COD, total nitrogen, ammonia nitrogen, and total phosphorus were 74.44%, 88.05%, 79.08%, and 82.69%, respectively. The total utilization rates of acetic acid, propionic acid, and butyric acid were 58.99%, 70.54%, and 81.52%, respectively. In addition, the highest lipid content of 39.15% and protein content of 42.43% achieved at the third cultivation. After the first cultivation, the composition and diversity of the microbial community structure changed dramatically, with Protebacteria, Bacteroidota, Hydrogenophaga, and Algoriphagus becoming enriched. These results showed a promising way of coupling wastewater treatment with biomass production for long-term sustainability of microalgae lipid production.

Prussian Blue Nanozyme Promotes the Survival Rate of Skin Flaps by Maintaining a Normal Microenvironment.

Ischemia-reperfusion (I/R) injury leads to a low success rate of skin flap transplantation in reconstruction surgery, thus requiring development of new treatments. Necroptosis and apoptosis pathways, along with overexpression of reactive oxygen species and pro-inflammatory factors in skin flap transplantation, are deemed as potential therapeutic targets. This study provides a paradigm for nanozyme-mediated microenvironment maintenance to improve the survival rate of the transplanted skin flap. Prussian blue nanozyme (PBzyme) with multiple intrinsic biological activities was constructed and selected for this proof-of-concept study. The prepared PBzyme shows anti-inflammatory, antiapoptotic, antinecroptotic, and antioxidant activities in both in vitro and in vivo models of I/R injured skin flaps. The multiple inhibitory effects of PBzyme maintained a normal microenvironment and thus significantly promoted the survival rate of the I/R injured skin flap (from 37.21 ± 8.205% to 79.61 ± 7.5%). Of note, PBzyme regulated the expression of the characteristic signal molecules of necroptosis, including Rip 1, Rip 3, and pMLKL, indicating that PBzyme may be a therapeutic agent for necroptosis-related diseases. This study shows great prospects for clinical application of PBzyme in the treatment of skin flaps via local administration.

The effect of volatile fatty acids on the growth and lipid properties of two microalgae strains during batch heterotrophic cultivation.

To overcome the bottlenecks of waste resource utilization and energy shortage that restrict the commercial production of microalgae biodiesel, volatile fatty acids (VFAs) derived from activated sludge were used as the sole carbon source to culture oleaginous microalgae Chlorella pyrenoidosa FACHB-1216 and Scenedesmus quadricauda FACHB-1297 under the mixotrophic and heterotrophic cultivation. Four VFAs ratios (acetic acids (AA): propionic acids (PA): butyric acids (BA)) were tested to determine the effects and mechanisms of the VFAs on the two microalgae. The highest lipid content (29.54%) and lipid production (71.10 mg L-1) were achieved by S. quadricauda at the VFAs ratio of 6: 1: 3 under heterotrophic condition, with 46.27% and 67.52% removal efficiencies of total nitrogen and phosphorus, respectively. The assimilation efficiency of AA was the highest at 73.37%, followed by that of PA and BA. For C. pyrenoidosa, VFAs promoted the rapid reproduction within 2 days under the heterotrophic condition at different initial inoculation densities. At the optimal VFA ratio, algae achieved the highest biomass concentration (0.14 ± 0.02 g L-1), with a specific growth rate of 0.91 d-1 and biomass productivity of 125.17 mg L-1 d-1. The removal rates of total nitrogen and phosphorus were 47.03% and 74.40%, respectively, and the assimilation efficiency of AA was the best (61.06%). High AA assimilation efficiency under the heterotrophic condition was beneficial for the algal growth and lipid accumulation. These results simultaneously produced microalgae-based bioenergy and recycled VFAs in anaerobically digested effluent.

Multi-Step Crystallization of Self-Organized Spiral Eutectics.

A method for the solidification of metallic alloys involving spiral self-organization is presented as a new strategy for producing large-area chiral patterns with emergent structural and optical properties, with attention to the underlying mechanism and dynamics. This study reports the discovery of a new growth mode for metastable, two-phase spiral patterns from a liquid metal. Crystallization proceeds via a non-classical, two-step pathway consisting of the initial formation of a polytetrahedral seed crystal, followed by ordering of two solid phases that nucleate heterogeneously on the seed and grow in a strongly coupled fashion. Crystallographic defects within the seed provide a template for spiral self-organization. These observations demonstrate the ubiquity of defect-mediated growth in multi-phase materials and establish a pathway toward bottom-up synthesis of chiral materials with an inter-phase spacing comparable to the wavelength of infrared light. Given that liquids often possess polytetrahedral short-range order, our results are applicable to many systems undergoing multi-step crystallization.

The Effect of Sulforaphane on the Activity and Mineralization of Osteoblasts under Oxidative Stress.

Sulforaphane (SFN) is considered an antioxidant agent, but the biological effects on hypoxia-treated osteoblasts remain unclear. Therefore, the aims of this study were to investigate the effects of SFN on the activity and mineralization of osteoblasts in hypoxia. Osteoblasts were treated with hypoxia with or without SFN, and apoptosis was assayed with caspase 3 Activity Assay Kit and flow cytometer. The levels of reactive oxygen species (ROS) were measured with DCFH-DA. The levels of glutathione (GSH) and glutathione disulphide were determined by the o-phthalaldehyde fluorimetric assay. Mineralization of Osteoblasts was detected by Alizarin red staining and alkaline phosphatase (ALP) staining, and the relative proteins levels were examined by Western blotting. Our results showed that SFN reduced the hypoxia-mediated apoptosis and ROS levels in osteoblasts. The utilization of SFN improved the inhibitory effect of osteoblast mineralization by hypoxia. Additionally, the effect of alleviating hypoxia by SFN will be an increase in osteoblast activity. These findings clarify the effects of SFN on hypoxia-treated osteogenesis and will help identify novel therapeutic strategies for the protection of skeletal health.

Comparison of effectiveness between complete internal limiting membrane peeling and internal limiting membrane peeling with preservation of the central fovea in combination with 25G vitrectomy for the treatment of high myopic foveoschisis.

Vitrectomy combined with internal limiting membrane peeling (ILMP) treats high myopic foveoschisis with good results, but there is a risk of iatrogenic macular holes, which may be reduced by preserving the internal limiting membrane of the central fovea. This study compared complete ILMP with partial ILMP, both combined with 25G vitrectomy, for the treatment of high myopic foveoschisis.Thirty-three cases (33 eyes) of high myopic foveoschisis were retrospectively analyzed. They underwent 25G vitrectomy combined with C3F8 gas filling; Group A (20 patients, 20 eyes) underwent complete ILMP, while Group B (13 patients, 13 eyes) underwent partial ILMP to preserve the internal limiting membrane of the central fovea. Patients were followed up for 6 months and underwent best corrected visual acuity (BCVA), intraocular pressure, diopter, slit lamp microscopy, indirect ophthalmoscope, A-mode and/or B-mode ultrasound, and optical coherence tomography. Surgical complications were recorded.Up to the last follow-up, the BCVA improved and central fovea thickness (CFT) was lower compared with before surgery in both groups (All P < .05). There were no significant differences in BCVA and CFT at each time point between the groups (P > .05). Most of the postoperative retinas of the 2 groups were completely reattached, with disappearance of the macular retinoschisis cavity. Two patients in the Group A and none in the Group B developed a macular hole during follow-up (P = .508).The results did not support the superiority of partial ILMP over complete ILMP in reduced incidence of macular hole. Both methods had a similar curative effect.

Synchronous front-face fluorescence spectroscopy for authentication of the adulteration of edible vegetable oil with refined used frying oil.

Synchronous front-face fluorescence spectroscopy has been developed for the discrimination of used frying oil (UFO) from edible vegetable oil (EVO), the estimation of the using time of UFO, and the determination of the adulteration of EVO with UFO. Both the heating time of laboratory prepared UFO and the adulteration of EVO with UFO could be determined by partial least squares regression (PLSR). To simulate the EVO adulteration with UFO, for each kind of oil, fifty adulterated samples at the adulterant amounts range of 1-50% were prepared. PLSR was then adopted to build the model and both full (leave-one-out) cross-validation and external validation were performed to evaluate the predictive ability. Under the optimum condition, the plots of observed versus predicted values exhibited high linearity (R(2)>0.96). The root mean square error of cross-validation (RMSECV) and root mean square error of prediction (RMSEP) were both lower than 3%.

Clinical analysis of early and mid-late elevated intraocular pressure after silicone oil injection.

PURPOSE: To discuss the incidence and clinical features of early and mid-late elevated intraocular pressure after pars plana vitrectomy and silicone oil injection, and to evaluate the clinical management of eyes with secondary glaucoma. METHODS: This was an observational consecutive case series of 691 eyes in 679 patients who were treated with pars plana vitrectomy and silicone injection. The diagnostic criteria of early elevated intraocular pressure after silicone oil injection was ≥ 21 mmHg two weeks after surgery, while mid-late elevated intraocular pressure was ≥ 21 mmHg after two weeks. The incidence and clinical management of elevated intraocular pressure were analyzed. RESULTS: In total, 211 of 691 eyes (30.54%) developed elevated intraocular pressure two weeks after pars plana vitrecto my and silicone injection. Of the 211 eyes, 101 eyes (47.87%) had ocular inflammation, 64 eyes (30.33%) showed hyphema, 35 eyes (16.59%) had silicone oil in the anterior chamber, 6 eyes (2.84% ) had excess silicone oil injected, and 5 eyes (2.37%) had rubeosis irides. Eighty three of 691 eyes (12.01%) developed elevated intraocular pressure after two weeks. Of these 83 eyes, 25 eyes (30.12%) had rubeosis irides, 16 eyes (19.27%) had issues related to topic steroid therapy, 13 eyes (15.66%) had a papillary block, silicone oil in the anterior chamber, 10 eyes (12.05%) had a silicone emulsion, 10 eyes (12.05%) had peripheral anterior synchiae, and 9 eyes (10.84%) had silicone oil in the anterior chamber. All eyes with elevated intraocular pressure were treated with antiglaucoma medications and surgeries. CONCLUSION: The reasons for elevated intraocular pressure differed between early and mid-late after pars plana vitrectomy and silicone oil injection. The elevated intraocular pressure can be controlled effectively by immediate diagnosis and proper treatment with medicine and operation.

[Effects of Jiangu granule containing serum on the cyclins in rat's osteoblast at G1 phase].

OBJECTIVE: To investigate the effects of Jiangu granule containing serum (JGG-serum) on the cyclins in rat's osteoblast at G1 phase. METHODS: Osteoblasts isolated by enzymatic digestion from SD rats were cultured and intervened with JGG-serum or normal saline (as control) respectively. Cell generation cycle was detected by flow cytometry, and expressions of Cyclin D1, cyclin-dependent kinase 4 (CDK4), oncogene protein (P21) in the osteoblast were detected dynamically using immuno-cytochemical and RT-PCR technique. RESULTS: As compared with the control, the cell generation cycle and cell proliferation were proceeding quicker in the JGG-serum (20%) intervention group; with higher protein and mRNA expressions of Cyclin D1 and CDK4, as well as much lowered expressions of P21 in nuclei of osteoblast detected at all time points (24 h, 48 h and 72 h after treatment, P < 0.05 or P < 0.01). CONCLUSION: JGG-serum can adjust the G1 phase cyclins in osteoblast cultured in vitro, increase the mRNA and protein expressions of Cyclin D1 and CDK4, and inhibit P21 expression, so as to accelerate the proliferation of osteoblast.

[Study on the correlations between the bone quality and level of u-DPD and serum 1,25-(OH)2D3 in the ovariectomized osteoporosis rats].

OBJECTIVE: To study the correlations between the bone quality and level of u-DPD and serum 1,25-dihydroxyvitamin D3 in the ovariectomized osteoporosis rats. METHODS: Forty female rats were randomly divided into the ovariectomy group (the OVX group) and the sham-operation group (the Sham group), and draw materials in 12 and 24 weeks after operation. Bone mineral density (BMD) of the 1st lumbar, the femoral neck and femur was measured by dual-energy X-ray absorptionetry. The level of urine DPD was measured by ELISA. The concentration of 1,25-dihydroxyvitamin D3 in serum was measured by radioimmunoassay (RIA). The limit of compressive strength and elastic modulus of 1st lumbar and bending load of right femur were measured by photoelasticity meter. The osseous morphology of upper tibia was measured by the non-decalcifing section. The correlation of experimental data was analyzed by statistical method. RESULTS: In ovariectomy group, except the level of urine DPD/Cr was increase, all data decreased significantly compared with the samp group,and descending continually with the lapse of time. The results showed that there was a negative correlation between the urine DPD/Cr and BMD of the 1st lumbar, femur, the limit of compressive strength of 1st lumbar, bending load of femur and trabecular bone area. But there was a positive correlation significantly between the concentration of 1,25-dihydroxyvitamin D3 in serum and BMD of the 1st lumbar, the femoral neck and femur, trabecular bone area, the limit of compressive strength of 1st lumbar, bend load of femur. CONCLUSION: The correlation is remarkable between the bone quality and the level of urine DPD/Cr, 1,25-dihydroxyvitamin D3 in serum. We can predict the bone quality by measuring the level of urine DPD/Cr and 1,25-dihydroxyvitamin D3 in serum.