Dihydrotanshinone I protects human chondrocytes and alleviates damage from spontaneous osteoarthritis in a guinea pig model.

Osteoarthritis (OA) is the most common degenerative joint disease. Currently, no satisfactory pharmacological treatment exists for OA. The potential anti-inflammatory properties of Dihydrotanshinone I (DHT) have been reported, but its effects on OA are unclear. In this study, we assess the impact of DHT on the viability of human chondrocytes in vitro. We then use a guinea pig model to investigate the effects of DHT on knee osteoarthritis progression. Twelve-week-old Dunkin Hartley guinea pigs spontaneously developing OA were intraperitoneally injected with different doses of DHT for eight weeks. Micro-CT analysis was performed on the subchondral bone in the knee, and histological assessment of the knee joint was done using stained sections, the ratio of hyaline to calcified cartilage, and Mankin scores. DHT successfully restored IL-1ß-induced decreases in cell viability in human primary chondrocytes. In the guinea pig model, intraperitoneal injections of DHT ameliorated age-induced OA, effectively reduced the expression level of two cartilage metabolism-related genes (ADAMTS4 and MMP13) and decreased the inflammatory biomarker IL-6 in the serum of guinea pigs developing spontaneous osteoarthritis. These findings demonstrate DHT's protective effects on chondrocytes and suggest that it alleviates cartilage degradation and proteoglycan loss in OA.

Early treatment for benign paroxysmal positional vertigo secondary to sudden sensorineural hearing loss.

Sudden sensorineural hearing loss (SSNHL) accompanied by benign paroxysmal positional vertigo (BPPV) is relatively common in the clinic. There are unified standards for the treatment of primary BPPV with good reduction effect, while there are few studies on the treatment of BPPV secondary to SSNHL within 1 week of onset. The study was to investigate the treatment of BPPV secondary to SSNHL and compare its manual reduction with that of primary BPPV. We selected 90 patients with BPPV accompanied by SSNHL within a week of onset and 210 primary BPPV patients at Hebei Provincial Eye Hospital from June 2020 to December 2022. The former group was divided into the medicine group and manual reduction plus medicine group. The medicines used were extract of Ginkgo biloba leaves injection, betahistine hydrochloride injection and oral prednisone. We contrasted the efficacy respectively for posterior semicircular canal BPPV (psc-BPPV), horizontal semicircular canal BPPV (hsc-BPPV) and multiple semicircular canal BPPV (msc-BPPV). In addition, we compared the manual reduction effect for primary BPPV and manual reduction group, and the evaluation of efficacy are the intensity of nystagmus and the clinical symptoms. In the secondary BPPV group, there was no difference in efficacy between the medicine group and manual reduction group at the 7th-day after reduction for psc-BPPV, hsc-BPPV, and msc-BPPV (P > .05). The immediate effect of reduction was significantly different between the primary BPPV group and the group with SSNHL and BPPV for both psc-BPPV and hsc-BPPV (P < .05), and the effect of the primary BPPV group was better, but it was no difference for msc-BPPV (P > .05). For the treatment of BPPV accompanied by SSNHL within 1 week of onset, the additional reduction therapy showed no benefit, so we need to apply medication for SSNHL.

Identification of Biomarker IL2Rß in Ankylosing Spondylitis via Multi-Chip Integration Analysis of Gene Differential Expression.

BACKGROUND: Ankylosing spondylitis (AS) is a chronic inflammatory autoimmune disease that affects axial joints such as the spine. Early diagnosis is essential to improve treatment outcomes. The purpose of this study is to uncover underlying genetic diagnostic features of AS. METHODS: We downloaded gene expression data from the Gene Expression Omnibus (GEO) database for three studies of groups of healthy and AS samples. After preprocessing and normalizing the data, we employed linear models to identify significant differentially expressed genes (DEGs) and further integrated the differential genes to acquire reliable differential transcriptional markers. Gene functional enrichment analysis was conducted to obtain enriched pathways and regulatory gene interactions were extracted from pathways to further elucidate pathway networks. Seventy-three reliably differentially expressed genes (DEGs) were integrated by differential analysis. Utilizing the regulatory relationships of the 21 Kyoto Encyclopedia of Genes and Genomes (KEGG) Pathway genes that were enriched in the analysis, a regulatory network of 622 genes was constructed and its topological properties were further analyzed. RESULTS: Functional enrichment analysis found 73 DEGs that were strongly associated with immune pathways like Th17, Th1 and Th2 cell differentiation. Using KEGG combined with DEGs, six hub genes (KLRD1, HLA-DRB3, HLA-DRB5, IL2Rß, CD247, and CXCL10) were suggested from the network. Of these, the IL2Rß gene was significantly differentially expressed compared with the normal control. CONCLUSION: IL2Rß (Interleukin-2 receptor beta) is strongly associated with the onset and progression of autoimmune joint diseases, and may be used as a potential biomarker of AS. This study offers new characteristics that can help in the diagnosis and individualized therapy of AS.

The Effects of Different Doses of Alfentanil and Dexmedetomidine on Prevention of Emergence Agitation in Pediatric Tonsillectomy and Adenoidectomy Surgery.

Background: Emergence agitation (EA) is a common problem often observed in children after sevoflurane anesthesia, which can be prevented by dexmedetomidine and alfentanil. This study aims to compare the effectiveness of dexmedetomidine alone and with different doses of alfentanil in preventing EA in children under sevoflurane anesthesia. Materials and Methods: In a double-blind trial, 80 children (ASA I or II, 3-7 years old) undergoing tonsillectomy alone and adenotonsillectomy with sevoflurane anesthesia were randomly assigned into four groups: the control group, dexmedetomidine (DEX) group, dexmedetomidine plus 10 µg/kg alfentanil group (DEX + Alf1), and dexmedetomidine plus 20 µg/kg alfentanil group (DEX + ALf2). The incidence of EA was assessed with the Aono's scale, and the severity of EA was evaluated with the Pediatric Anesthesia Emergence Delirium (PAED) scale. The time of tracheal extubation and time of wake were recorded. Postoperative pain and complications such as nausea and vomiting, cough, laryngospasm, and bradycardia were recorded. Results: The incidence of EA was 50% in the control group, 25% in the DEX group, and 5% in the DEX + Alf1 group, and it never happened in the DEX + Alf2 group. The Aono's scale, the PAED scale, and the FLACC scale in the control group and the DEX group were significantly more than those in the DEX + Alf1 group and the DEX + Alf2 group after the tracheal extubation (p < 0.05). The time of tracheal extubation of the control group and the DEX group were significantly shorter than those in the DEX + Alf1 group and the DEX + Alf2 group (p < 0.05). The awakening time of the DEX + Alf2 group is significantly longer than those in other groups (p < 0.05). The case of postoperative nausea and vomiting in the DEX + Alf1 group was fewer than those in the other groups (p < 0.05). And, the cases of cough and laryngospasm and bronchospasm in the DEX + Alf1 group and the DEX + Alf2 group were significantly less than those in the control group and the DEX group after the tracheal extubation (p < 0.05). Conclusion: The combined administration of alfentanil and dexmedetomidine can reduce EA in children undergoing tonsillectomy alone and adenotonsillectomy with sevoflurane anesthesia. Dexmedetomidine plus 10 µg/kg alfentanil seems to be more appropriate than other dose combinations as it reduced EA and postoperative nausea and vomiting but did not prolong the time to awake.

Low­calorie sweetener D­psicose promotes hydrogen peroxide­mediated apoptosis in C2C12 myogenic cells favoring skeletal muscle cell injury.

Diet and exercise are the most effective approaches used to induce weight loss. D­psicose is a low­calorie sweetener that has been shown to reduce weight in obese individuals. However, the effect of D­psicose on muscle cells under oxidative stress, which is produced during exercise, requires further investigation. The present study aimed to determine the effects of D­psicose on C2C12 myogenic cells in vitro. Hydrogen peroxide (H2O2) was used to stimulate the generation of intracellular reactive oxygen species (ROS) in muscle cells to mimic exercise conditions. Cell viability was analyzed using a MTT assay and flow cytometry was used to analyze the levels of apoptosis, mitochondrial membrane potential (MMP), the generation of ROS and the cell cycle distribution following treatment. Furthermore, protein expression levels were analyzed using western blotting and cell proliferation was determined using a colony formation assay. The results of the present study revealed that D­psicose alone exerted no toxicity on C2C12 mouse myogenic cells. However, in the presence of low­dose (100 µM) H2O2­induced ROS, D­psicose induced C2C12 cell injury and significantly decreased C2C12 cell viability in a dose­dependent manner. In addition, the levels of apoptosis and the generation of ROS increased, while the MMP decreased. MAPK family molecules were also activated in a dose­dependent manner following treatment. Notably, the combined treatment induced G2/M phase arrest and reduced the proliferation of C2C12 cells. In conclusion, the findings of the present study suggested that D­psicose may induce toxic effects on muscle cells in a simulated exercise situation by increasing ROS levels, activating the MAPK signaling pathway and disrupting the MMP.

The Protective Effect and Mechanism of Dexmedetomidine on Diabetic Peripheral Neuropathy in Rats.

OBJECTIVE: To investigate the role of dexmedetomidine (DEX) in the inhibition of diabetic peripheral neuropathy (DPN) and the protection in the nerve damage. METHODS: Eighty male Sprague-Dawley (SD) rats were randomly allocated to four groups: the control group (C group), DPN model group (DPN group), DEX-treated group (DEX group), and the yohimbine treated group (YOH group). DPN was induced by intraperitoneal administration of streptozocin (STZ) (35 mg/kg). The body weights, blood glucose level, mechanical withdrawal threshold (MWT), thermal withdrawal latency (TWL), the motor, and sensory nerve conduction velocities (MNCV and SNCV) of sciatic nerve were measured. Then the sciatic nerve was isolated for H&E staining and immunohistochemical staining. The oxidative stress makers such as malondialdehyde (MDA), superoxide-dismutase (SOD), and glutathione peroxidase (GSH-Px) and apoptosis related cytokines such as Bax, Bcl-2, and caspase-3 were estimated. RESULTS: There was no significant difference of the blood glucose and body weight among the DPN group, DEX group, and YOH group. H&E staining showed that DEX treatment can ameliorate the damage of sciatic nerve cells. In the DPN group, MWT, TWL, MNCV, and SNCV were significantly reduced compared with the C group (P < 0.05). In DEX group rats, MWT, TWL, MNCV, and SNCV were increased significantly (P < 0.05) compared with the DPN group and YOH group rats. Lower SOD and GSH-Px, and higher MDA were found in the DPN group compared with the C group (P < 0.01), and DEX treatment restored SOD, GSH-px, and MDA activity significantly (P < 0.01). The expression levels of Bax and caspase-3 were increased, while that of Bcl-2 was decreased significantly in the DPN group compared with the C group (P < 0.05). In the DEX group, the expression levels of Bax and caspase-3 were decreased significantly (P < 0.05), while that of Bcl-2 was increased significantly (P < 0.05) compared with the DPN group and the YOH group. CONCLUSION: The results of this study demonstrated that DEX has the inhibitory and protective effects on DPN of rats. This may be associated with its antioxidative and anti-apoptosis responses.

Effect of Different Doses of Intrathecal Dexmedetomidine as an Adjuvant Combined With Hyperbaric Ropivacaine in Patients Undergoing Cesarean Section.

OBJECTIVE: In this study, we aim to investigate the effect of different doses of dexmedetomidine as an adjuvant to hyperbaric ropivacaine in spinal anesthesia for cesarean section. METHODS: Seventy-five parturients with American Society of Anesthesiologists (ASA) I or II were anesthetized with intrathecal ropivacaine (12.5 mg) alone (R group) or in combination with dexmedetomidine 3 µg (RD3 group) and 5 µg (RD5 group) to undergo a cesarean section. The anesthetic parameters, postoperative analgesia, stress responses and neonates outcomes were monitored. RESULTS: The onset time of sensory block to T10, T4, and peak level in the RD3 group and RD5 group were significantly shorter than those in the R group (p < 0.05). The time of the level of sensory block to descend two segments and to T10 in the RD3 group(57.28 ± 16.65 min, 3.87 ± 1.60 h) and RD5 group (71.92 ± 10.10 min, 3.99 ± 1.06 h) were longer than that in the R group (40.64 ± 12.06 min, 1.98 ± 1.01 h) (p < 0.05). The median time of motor blockade to both legs score 3 on the Bromage scale (B3B3) in the RD3 group and RD5 group was shorter than that in the R group (p < 0.001). The time of motor blockade recovery to both legs score 0 on the Bromage scale (B0B0) in the RD5 group (3.6 h) was longer than that in the R group (2 h) or RD3 group (2.2 h) (p < 0.001). Visceral traction response and abdominal muscle relaxation during the operation in the RD3 group and the RD5 group were better than that in the R group. The Visual Analogue Score (VAS) in the 12 h after the operation in the RD3 group (3.30 ± 1.17) and RD5 group (2.80 ± 0.87) was smaller than that in the R group (3.80 ± 1.47) (p < 0.05). The incidence of shivering in the RD3 group and RD5 group was significantly lower than that in the R group (p < 0.05). The postoperative concentrations of c-reactive protein (CRP), interleukin-6 (IL-6) and cortisol in the RD3 and RD5 groups were lower than that in the R group (p < 0.05). CONCLUSION: 3 µg intrathecal dexmedetomidine as an adjuvant to ropivacaine improved intraoperative somato-visceral sensory block characteristics and postoperative analgesia, alleviated shivering in parturients, and did not prolong the time of motor block or produce any side effects, which makes this dose appropriate for cesarean delivery. CINICAL TRIAL REGISTRATION: ChiCTR, identifier ChiCTR1800014454. Registered 15 January 2018, http://www.chictr.org.cn/edit.aspx?pid=24613&htm=4.

Optimal Dexmedetomidine Dose to Prevent Emergence Agitation Under Sevoflurane and Remifentanil Anesthesia During Pediatric Tonsillectomy and Adenoidectomy.

Background: Emergence agitation (EA) is a common pediatric complication after sevoflurane anesthesia that can be prevented with dexmedetomidine. However, an inappropriate dose of dexmedetomidine can cause prolonged sedation and cardiovascular complications. Thus, we evaluated the optimal dose (ED95) of dexmedetomidine for preventing EA with sevoflurane and remifentanil anesthesia after pediatric tonsillectomy and adenoidectomy. Methods: We enrolled American Society of Anesthesiologists (ASA) I and II children 3-7 years of age who underwent tonsillectomy with adenoidectomy. During induction, dexmedetomidine was infused for 10 min. Anesthesia was induced with sevoflurane and maintained with sevoflurane and remifentanil, resulting in a bispectral spectrum index (BIS) range from 40 to 60. Extubation time, surgical and anesthetic duration time, and duration time in the postanesthesia care unit (PACU) stay were recorded. EA [measured with Pediatric Anaesthesia Emergence Delirium (PAED) scores] and pain [measured with Face, Legs, Activity, Cry, Consolability (FLACC) scores] were assessed at extubation (E0), 15 min after extubation (E1), and 30 min after extubation (E2). If EA occurred, the next surgical procedure included increased dexmedetomidine by 0.1 µg/kg, and if not, the drug was reduced by 0.1 µg/kg. Results: The 50% effective dose (ED50) of dexmedetomidine for preventing EA after sevoflurane and remifentanil anesthesia for tonsillectomy and adenoidectomy was 0.13 µg/kg, and its 95% confidence interval is 0.09-0.19 µg/kg; ED95 was 0.30 µg/kg, and its 95% confidence interval is 0.21-1.00 µg/kg. Conclusion: Intravenous dexmedetomidine infusion at ED50 (0.13 µg/kg) or ED95 (0.30 µg/kg) during induction for 10 min can prevent half or almost all EA after sevoflurane and remifentanil anesthesia during pediatric tonsillectomy and adenoidectomy.

Low dose of dexmedetomidine as an adjuvant to bupivacaine in cesarean surgery provides better intraoperative somato-visceral sensory block characteristics and postoperative analgesia.

OBJECT: In this study, we aimed to investigate the beneficial effects of dexmedetomidine on somato-visceral sensory block characteristcs, postoperative analgesia and stress response of intrathecal bupivacaine administration in women undergoing cesarean section, and to find out which dose is better. METHODS: Sixty parturients with the American Society of Anesthesiologists (ASA) physical status I or II were anesthetized with intrathecal bupivacaine(10mg) alone or in combination with dexmedetomidine (3 µg and 5 µg) to undergo cesarean section. The anesthetic parameters, postoperative analgesia and stress responses were monitored. RESULTS: Co-administration of dexmedetomidine(3 µg and 5 µg) prolonged the duration of motor and sensory block compared with bupivacaine(10mg) alone. Less supplemental dose of lidocaine and fentanyl were required in dexmedetomidine(3 µg and 5 µg) co-administration groups. Visceral traction response and abdominal muscle relaxation in operation were better in dexmedetomidine(3 µg and 5 µg) co-administration groups. No difference in haemodynamics was detected among groups. There was no significant difference in Apgar scores, neonatal umbilical pH, oxygen pressure, carbon dioxide pressure and lactate level among groups. Postoperative plasma IL-6 and cortisol levels were lower in dexmedetomidine(3 µg and 5 µg) co-administration groups. At 6 hour after operation the visual analogue scale (VAS) was smaller in dexmedetomidine(3 µg and 5 µg) co-administration groups. The uterine contraction pain at 6 and 12 hour after operation and supplemental analgesics had no difference across three groups. No difference of side effects(shivering, nausea and vomiting, itching), the first anal aerofluxus time and intraoperation tramadol dose were detected among the three groups. CONCLUSION: The use of dexmedetomidine especially at the dose of 3µg as an adjuvant to bupivacaine in cesarean surgery provides better intraoperative somato-visceral sensory block characteristcs and postoperative analgesia, which produced no influence on Apgar scores, side effects and stress response.

Adsorption behavior of modified Iron stick yam skin with Polyethyleneimine as a potential biosorbent for the removal of anionic dyes in single and ternary systems at low temperature.

The skin of Iron stick yam (ISY) was modified with Polyethyleneimine (ISY@PEI) and evaluated for use as a potential biosorbent to remove the anionic dyes Sunset yellow (SY), Lemon yellow (LY), and Carmine (CM) from wastewater under low temperature conditions (5-15°C) in single and ternary dye systems. Both in the single and ternary systems, experimental data showed that adsorption capacity reached the highest value at 5°C, and adsorption capacity decreased when the temperature increased (10-50°C). The equilibrium data fitted very well to the Langmuir model and the extended Langmuir isotherm, for the single and ternary systems, respectively. The maximum adsorption capability was 138.92, 476.31, and 500.13mg/g for LY, SY, and CM, respectively, in a single system and 36.63, 303.31, and 294.12mg/g for LY, SY, and CM, respectively, in a ternary system. The adsorption followed pseudo-second-order kinetics. The thermodynamic parameters indicated that it was a spontaneous and exothermic process.

The inhibitory effect of propofol on Kv2.1 potassium channel in rat parietal cortical neurons.

Excessive K(+) efflux via activated voltage-gated K(+) channels can deplete intracellular K(+) and lead to long-lasting membrane depolarization which will promote neuronal apoptosis during ischemia/hypoxia injury. The Kv2.1 potassium channel was the major component of delayed rectifier potassium current (Ik) in pyramidal neurons in cortex and hippocampus. The neuronal protective effect of propofol has been proved. Delayed rectifier potassium current (Ik) has been shown to have close relationship with neuronal damage. The study was designed to test the inhibitory effect of propofol on Kv2.1 potassium channel in rat parietal cortical neurons. Whole-cell patch clamp recordings and Western blot analysis were used to investigate the electrophysiological function and protein expression of Kv2.1 in rat parietal cortical neurons after propofol treatment. We found that propofol concentration-dependently inhibited Ik in pyramidal neurons. Propofol also caused a downward shift of the I-V curve of Ik at 30µM concentration. Propofol significantly inhibited the expression of Kv2.1 protein level at 30µM, 50µM, 100µM concentration. In conclusion, our data showed that propofol could inhibit Ik, probably via depressing the expression of Kv2.1 protein in rat cerebral parietal cortical neurons.

Effect of the CYP2D6 gene polymorphism on postoperative analgesia of tramadol in Han nationality nephrectomy patients.

OBJECTIVE: Tramadol is a synthetic opioid which has analgesic efficacy in the postoperative pain. It is metabolized by polymorphic enzyme cytochrome P450 (CYP2D6). Patients with different CYP2D6 genotypes would have different responses to tramadol in pain relief. The CYP2D6*10 allele is the most common allele in a Chinese population. The aim of this study was to evaluate whether the different CYP2D6*10 genotypes have an effect on the postoperative tramadol analgesia in the Chinese population after elective nephrectomy. METHODS: One hundred and twenty patients after performed elective nephrectomy were enrolled in this study after being approved by the local Ethics Committee. The patients were given patient-controlled analgesia (PCA) which included 10 mg/ml tramadol after receiving a loading dose of 100 mg tramadol and 1 mg granisetron intravenously. Blood samples were collected after induction of anesthesia. The CYP2D6*10 polymorphism was analyzed by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). According to the results, the patients were divided into three groups (CYP2D6*1/*1, n = 33; CYP2D6*1/*10, n = 28; CYP2D6*10/*10, n = 50). The total consumption of tramadol, visual analogue scale (VAS) score, and PCA control times among the three genotype groups for 2, 4, 24, 48, and 72 h after operation were compared. RESULTS: Nine out of 120 patients were dropped out of the study; 111 patients completed the study. The frequency of CYP2D6*10 allele was 57.7%. The demographic data among the three groups were comparable. The consumption of tramadol, patient self-control times of pump, and VAS score in CYP2D6*10/*10 group were significantly higher than that in CYP2D6*1/*1 or CYP2D6*1/*10 group at 2 and 4 h (P < 0.05), while it did not differ between CYP2D6*1/*1 and CYP2D6*1/*10 group (P > 0.05). There was no difference in the incidence of nausea and vomiting among the three groups (P > 0.05). No sever apnea was recorded in these groups. CONCLUSIONS: Different CYP2D6*10 genotypes have an influence on the analgesic effect of tramadol in Han nationality patients after elective nephrectomy.

Planting sentinel European trees in eastern Asia as a novel method to identify potential insect pest invaders.

Quarantine measures to prevent insect invasions tend to focus on well-known pests but a large proportion of the recent invaders were not known to cause significant damage in their native range, or were not even known to science before their introduction. A novel method is proposed to detect new potential pests of woody plants in their region of origin before they are introduced to a new continent. Since Asia is currently considered to be the main supplier of insect invaders to Europe, sentinel trees were planted in China during 2007-2011 as an early warning tool to identify the potential for additional Asian insect species to colonize European trees. Seedlings (1-1.5 m tall) of five broadleaved (Quercus petraea, Q. suber, Q. ilex, Fagus sylvatica, and Carpinus betulus) and two conifer species (Abies alba and Cupressus sempervirens) were planted in blocks of 100 seedlings at two widely separated sites (one in a nursery near Beijing and the other in a forest environment near Fuyang in eastern China), and then regularly surveyed for colonization by insects. A total of 104 insect species, mostly defoliators, were observed on these new hosts, and at least six species were capable of larval development. Although a number of the insects observed were probably incidental feeders, 38 species had more than five colonization events, mostly infesting Q. petraea, and could be considered as being capable of switching to European trees if introduced to Europe. Three years was shown to be an appropriate duration for the experiment, since the rate of colonization then tended to plateau. A majority of the identified species appeared to have switched from agricultural crops and fruit trees rather than from forest trees. Although these results are promising, the method is not appropriate for xylophagous pests and other groups developing on larger trees. Apart from the logistical problems, the identification to species level of the specimens collected was a major difficulty. This situation could be improved by the development of molecular databases.

[Relationship between 666C > T polymorphism of TIMP-1 and lumbar intervertebral disc degeneration].

OBJECTIVE: To detect the single nucleotide polymorphisms (SNPs) in exon 6 of tissue inhibitor of metalloproteinase-1 (TIMP-1) in young men in North China and to investigate the relationship between these polymorphisms and lumbar intervertebral disc degeneration. METHODS: The recruited subjects aged from 18 to 40 years old were divided by MRI into degeneration group (n = 48) and non-degeneration group (n = 49). The genomic DNA was collected from blood. After PCR amplification, the SNPs of TIMP-1 exon 6 were detected by DNA sequencing. RESULTS: Only the TIMP-1 666C > T (rs11551797) polymorphism was observed and the genotype was of homozygote (CC/TT). The difference between two group was statistically significant (χ(2) = 4.571, P = 0.033). Although the polymorphism was a synonymous mutation, the TT genotype mutant type was one of the risk factors for lumbar intervertebral disc degeneration (OR = 3.269, 95%CI 1.063 - 10.047). In the degeneration group, no significant correlation was found between the polymorphism, extent, level and number of degenerated intervertebral discs. CONCLUSION: TIMP-1 666C > T polymorphism present in north Chinese young men may lead to lumbar intervertebral disc degeneration. However it has no effect on the degree, level and number of degenerated intervertebral discs.

Host specificity of Argopistes tsekooni (Coleoptera: Chrysomelidae), a potential biological control agent of Chinese privet.

Chinese privet, Ligustrum sinense Lour., is a perennial semi-evergreen shrub that is a serious invasive weed in the United States. Classical biological control offers the best hope for controlling it in an economic, effective, and persistent way. Host specificity of one of the most promising biological control agents of Chinese privet, a flea beetle, Argopistes tsekooni Chen (Coleoptera: Chrysomelidae), was evaluated in China by using laboratory no-choice and choice tests on 13 species of Oleaceae and eight species in other families that have important economic value. In adult no-choice survival and oviposition tests, the flea beetle fed and survived for 30 d on Syringa oblata Lindl., Jasminum nudiflorum Lindl., and three species in the genus Ligustrum. Females also oviposited on these species, but only larvae from eggs laid on S. oblata and Ligustrum spp. developed successfully. In addition, the beetles did not feed or oviposit on the species of economic importance. In choice tests, adults preferred L. sinense for feeding and oviposition. These results show that A. tsekooni is relatively host specific and warrants further testing as a biocontrol agent of Chinese privet in the United States.