Tooth Discoloration from 2 Silver Fluorides Used in Adults with Special Needs: A Randomized Trial

BACKGROUND

Discoloration of carious lesions after application of silver diamine fluoride lowers patient acceptance and limits its wider use for caries arrest.

OBJECTIVE

To assess lesion and tooth color changes from 2 novel silver fluoride (AgF) products and its relationship to caries activity (clinical visuo-tactile scores) and bacterial load (using laser fluorescence with the DIAGNOdent).

METHODS

A split-mouth design was followed, with matched smooth surface carious lesions in the same arch in adults with special needs randomized for 1-min treatments with AgF/potassium iodide (KI) (Riva Star Aqua, SDI) and AgF/stannous fluoride (SnF2) (Caries Status Disclosing Solution; Whiteley). Standardized images taken at baseline, immediately postoperatively, and at 3-mo review were subjected to digital image analysis to calculate delta-E and to track changes in luminosity of carious lesions.

RESULTS

Twelve participants were recruited in the study. A total of 56 teeth (28 pairs) were included. Significantly greater changes were seen in treated lesions than in the adjacent noncarious natural tooth structure, both immediately after treatment and at the 3-mo review (P < 0.0001). Color change and caries activity were not affected by tooth type, tooth location, plaque status, salivary status, or special needs condition. AgF/SnF2 caused transitory darkening immediately on application, while AgF/KI caused the immediate formation of yellow deposits (silver iodide). Both products caused significant darkening of treated lesions at 3 mo (P = 0.0009; P = 0.0361), with no differences between them (P = 0.506). Responding lesions showed larger and more perceptible color changes immediately after either AgF application (P = 0.002; P = 0.024).

CONCLUSIONS

Both AgF products were highly effective for caries arrest in this patient population. Despite minor differences in the appearance of treated lesions at the time of application, both products lead to similar darkening of treated sites at 3 mo.

KNOWLEDGE TRANSFER STATEMENT

This study shows the usefulness of silver fluoride used in conjunction with potassium iodide or stannous fluoride for achieving caries arrest in smooth surface lesions in adults with special needs. Patients need to be informed that long-term staining of the lesion occurs with both, similar to silver diamine fluoride.

A splice acceptor variant in RGS6 associated with intellectual disability, microcephaly, and cataracts disproportionately promotes expression of a subset of RGS6 isoforms

Intellectual disability (ID) is associated with an increased risk of developing psychiatric disorders, suggesting a common underlying genetic factor. Importantly, altered signaling and/or expression of regulator of G protein signaling 6 (RGS6) is associated with ID and numerous psychiatric disorders. RGS6 is highly conserved and undergoes complex alternative mRNA splicing producing ~36 protein isoforms with high sequence similarity historically necessitating a global approach in functional studies. However, our recent analysis in mice revealed RGS6 is most highly expressed in CNS with RGS6L(+GGL) isoforms predominating. A previously reported genetic variant in intron 17 of RGS6 (c.1369-1G>C), associated with ID, may provide further clues into RGS6L(+GGL) isoform functional delineation. This variant was predicted to alter a highly conserved canonical 3' acceptor site creating an alternative branch point within exon 18 (included in a subset of RGS6L(+GGL) transcripts) and a frameshift forming an early stop codon. We previously identified this alternative splice site and demonstrated its use generates RGS6Lζ(+GGL) isoforms. Here, we show that the c.1369-1G>C variant disrupts the canonical, preferred (>90%) intron 17 splice site and leads to the exclusive use of the alternate exon 18 splice site, inducing disproportionate expression of a subset of isoforms, particularly RGS6Lζ(+GGL). Furthermore, RGS6 global knockout mice do not exhibit ID. Thus, ID caused by the c.1369-1G>C variant likely results from altered RGS6 isoform expression, rather than RGS6 isoform loss. In summary, these studies highlight the importance of proper RGS6 splicing and identify a previously unrecognized role of G protein signaling in ID.

Intra-Articular Injection of Interleukin-8 Neutralizing Monoclonal Antibody Effectively Attenuates Osteoarthritis Progression in Rabbits

OBJECTIVE

Cytokines are implicated in the pathogenesis of osteoarthritis (OA), and this study aims to assess the therapeutic potential of an IL-8 neutralizing monoclonal antibody (mAb) for OA intervention.

DESIGN

The study employed a rabbit model of OA induced by anterior cruciate ligament transection (ACLT) surgery to investigate the effects of an interleukin (IL)-8 neutralizing mAb, with hyaluronic acid (HA) used as a positive control. Primary outcomes assessed in the rabbits included cartilage repair, synovitis, joint effusion, changes in footprints, and lower limb loading conditions.

RESULTS

Compared to HA, intra-articular injection of the IL-8 neutralizing mAb demonstrated a more pronounced attenuation of OA progression and enhancement of cartilage repair. We observed a reduction in synovitis and joint effusion, indications of bone marrow edema, as well as improvements in lower limb function. In knees treated with the neutralizing IL-8 mAb, there was a significant decrease in IL-8 levels within the synovial tissues.

CONCLUSIONS

The IL-8 neutralizing mAb exhibits promising therapeutic potential in the management of OA by attenuating inflammation and facilitating cartilage repair. However, further investigations are warranted to comprehensively elucidate the underlying mechanisms, optimize treatment protocols, and ensure the long-term safety and efficacy of this innovative therapeutic approach.

A Torn Discoid Lateral Meniscus Impacts Lower-Limb Alignment Regardless of Age: Surgical Treatment May Not Be Appropriate for an Asymptomatic Discoid Lateral Meniscus

BACKGROUND

A discoid lateral meniscus (DLM) is more prone to tear, and treatment of this condition is challenging. The purpose of the present study was to investigate (1) whether a torn DLM is associated with more varus alignment than a torn semilunar lateral meniscus (SLM) and (2) whether the lower-limb alignment associated with a torn DLM changes with age.

METHODS

Consecutive patients who underwent arthroscopic knee surgery for a torn lateral meniscus were included. Patients with a torn DLM (confirmed on arthroscopy) were allocated to the DLM group; those with a torn SLM were allocated to the SLM group. After strict screening according to the inclusion and exclusion criteria, 436 and 423 patients were included in the DLM and SLM groups, respectively. The mechanical axis deviation (MAD), hip-knee-ankle angle (HKA), mechanical lateral distal femoral angle, and medial proximal tibial angle were compared between the 2 groups after propensity score matching. Additionally, the correlation of the HKA and MAD with age was evaluated within the DLM group.

RESULTS

After propensity score matching, all baseline characteristics were well balanced between the 2 groups. The DLM group had significantly more varus alignment than the SLM group (MAD: 3.6 mm ± 9.6 mm versus 1.1 mm ± 10.3 mm, respectively, p = 0.001; HKA: 179.1° ± 2.9° versus 179.9° ± 3.0°, respectively, p = 0.001). Within the DLM group, the MAD (R = 0.10, p = 0.032) and HKA (R = -0.13, p = 0.007) had a weak correlation with age.

CONCLUSIONS

Patients with a torn DLM had more varus knee alignment than those with a torn SLM, and this trend did not increase with age after minimizing the effects of osteoarthritis. Therefore, surgical treatment may not be appropriate for asymptomatic DLM.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

A case report: anatomical translocation in tibial insertion of semitendinosus tendon after tibial lengthening

Background

There is the most common method for arthroscopic anterior cruciate ligament (ACL) reconstruction by using the semitendinosus and gracilis tendons and single-tunnel technique. However, anatomic translocation of hamstring tendon attachment is very rare.

Case presentation

A 45-year-old male who need to receive right knee ACL reconstruction due to sprain injury while playing table tennis was found to have a translocation at tibial attachment of semitendinosus tendon. The tibial insertion of left semitendinosus was then explored by ultrasound and found to be identical to the contralateral limb. The patient has a history of bilateral tibial lengthening.

Conclusions

This is the first case as far as we know that reported anatomic translocation of the tibial attachment of the hamstring tendon after tibial lengthening. Surgeons should be aware of this specific situation when hamstring tendon need to be harvested to avoid unnecessary complications.

[A time-series study on the association of ambient temperature with daily outpatient visits of eczema in Huizhou city]

Objective: To explore the impact of environmental temperature exposure on eczema visits. Methods: Eczema clinic data from January 1, 2016 to December 31, 2019 were collected from the Huizhou Dermatology Hospital, and data on meteorological factors (average daily temperature and relative humidity) for the same period were derived from 86 meteorological stations of the Guangdong Provincial Climate Center. A distributed lag nonlinear model (DLNM) was used to assess the lagged effect of environmental temperature exposure on eczema, and a natural smooth spline function was used to control the nonlinear confounding of humidity. Results: There were 254 053 eczema outpatient visits at the Huizhou Dermatology Hospital within four years, with an average of 173.89 visits per day. The relationship between daily average temperature and the number of visits was non-linear (U shape). The risk of eczema increased by 2.20% (1.19%-3.21%) for every 1 ℃ decrease for the low temperature, and increased by 2.35% (1.24%-3.5%) for every 1 ℃ increase for the high temperature. The effect of high temperature was greater than that of low temperature. In all cases, 1.60% (0.44%-2.68%) of eczema outpatient visits were attributed to low temperature and the attributable number was 4 065 (1 128-6 798), while 6.33% (1.40%-10.87%) of eczema outpatient visits were due to high temperature and the attributable number was 16 082 (3 557-27 616). Conclusion: Both high temperature and low temperature are associated with increased risk of eczema.

Application of three-dimensional-printed porous tantalum cones in total knee arthroplasty revision to reconstruct bone defects

Purpose: Three-dimensional (3D) printing technology has emerged as a new treatment method due to its precision and personalization. This study aims to explore the application of a 3D-printed personalized porous tantalum cone for reconstructing the bone defect in total knee arthroplasty (TKA) revision.

Methods: Between November 2017 and October 2020, six patients underwent bone reconstruction using 3D-printed porous tantalum cones in TKA revision. The knee function was assessed using the Hospital for Special Surgery (HSS) score pre- and postoperatively. The pain was measured by the visual analog scale (VAS) pre- and postoperatively. The quality of life was measured using the 36-Item Short Form Health Survey (SF-36) to pre- and postoperatively evaluate the relief of pain. Operation time, intraoperative blood loss, postoperative drainage volume, and complications were also recorded. At the last follow-up, all patients received X-ray and computed tomography (CT) to confirm the effect of bone reconstruction.

Results: After an average follow-up duration of 26.3 months, no patients developed any operation-related complications. The average intraoperative blood loss and postoperative drainage volumes were 250.1 ± 76.4 ml and 506.7 ± 300.8 ml, respectively. At the last follow-up, the HSS score was significantly higher than that before operation, indicating that the knee function was significantly improved (p < 0.001). During the follow-up, the mean VAS score decreased and the mean SF-36 score increased, both of which were significantly improved compared with preoperative conditions (p < 0.001). Radiological examination at the final follow-up showed that cones implanted into the joint were stable and bone defects were effectively reconstructed.

Conclusion: This study demonstrated that 3D-printed porous tantalum cones could effectively reconstruct bone defects and offer anatomical support in TKA revision. Further studies are still needed to confirm the long-term effect of 3D-printed tantalum cones for reconstructing bone defects.

Methacrylated pullulan/polyethylene (glycol) diacrylate composite hydrogel for cartilage tissue engineering

Pullulan hydrogels are widely used in tissue engineering and drug delivery. However, these hydrogels do not meet the requirements of articular cartilage repair because of their fast degradation rate and poor mechanical strength. Herein, we fabricated a hybrid hydrogel system by combining pullulan with synthetic polymers polyethylene (glycol) diacrylate (PEGDA). In this study, pullulan was modified with methacrylic anhydride (MA) to obtain photo-crosslinkable methacrylated pullulan (PulMA). Moreover, the lithium phenyl(2,4,6-trimethylbenzoyl)phosphinate (LAP) was used as a water-soluble UV photoinitiator to form the PulMA/PEGDA hydrogel by photopolymerization strategy. Compared with the pure PulMA hydrogel, the increase of PEGDA concentration led to a slower degradation rate and an increase of residual mass from 63.9% to 86.8%. There was about 8-fold increase in storage modulus (G') (reach to 16.0 × 10³ Pa) and 13-fold increase in compressive modulus (reach to 1.17 ± 0.17 MPa) with increasing the concentration of PEGDA to 15% (w/v) in the hydrogel. In cell culture in vitro, the rabbit's mesenchymal stem cells (MSCs) encapsulated in the PulMA/PEGDA hydrogel could adhere and proliferate, indicating that the PulMA/PEGDA hydrogel had a good biocompatibility. Furthermore, the hydrogels supported glycosaminoglycan (GAG) synthesis, and chondrogenic phenotype of MSCs with TGF-β3-containing chondrogenic medium. This study demonstrated that the photo-crosslinking PulMA/PEGDA hydrogels, with good mechanical properties and slow degradation rate are promising scaffolds for cartilage repair and regeneration.

Tear inflammatory cytokines and ocular surface changes in patients with active thyroid eye disease treated with high-dose intravenous glucocorticoids

PURPOSE

To evaluate high-dose intravenous glucocorticoid treatment on tear inflammatory cytokines and ocular surface parameters in patients with active TED. Correlations between tear inflammatory cytokines and clinical parameters were also investigated.

METHODS

This prospective pilot study included 15 moderate-to-severe and active TED patients. Control group consist of 15 sex and age-matched healthy subjects. All TED patients were treated with high-dose intravenous methylprednisolone with cumulative dose of 4.5 g during the therapy subdivided into 12 weekly infusions. Tear concentrations of interleukin (IL)-1β, IL-6, IL-8, IL-10, IL-17A, tumor necrosis factor (TNF)-α, and vascular endothelial growth factor (VEGF) were measured by multiplex bead analysis in TED patients at baseline and 12 weeks after treatment. Ocular surface disease index (OSDI), tear break-up time (TBUT), corneal fluorescent staining, and Schirmer's test were obtained from TED and controls.

RESULTS

All baseline cytokine levels except for IL-17A were significantly elevated in active TED patients compared with controls. Concentrations of IL-1β, IL-6, IL-8, TNF-α, and VEGF were significantly decreased at 12 weeks compared with baseline. OSDI and TBUT showed significant improvement at 6 and 12 weeks. There were significant positive correlations between IL-6, IL-8, and CAS, and negative correlation was found between IL-6 level and TED duration before methylprednisolone treatment. The reduction of IL-6, IL-8, and VEGF were positive correlated with the reduction in CAS at 12 weeks.

CONCLUSIONS

High-dose glucocorticoids treatment improved ocular surface symptom, increased the tear film stability, and decreased tear inflammatory cytokines in active TED. The reduction of the inflammatory cytokines is consistent with the improvement of clinical parameters.

Circulating miR-374b-5p negatively regulates osteoblast differentiation in the progression of osteoporosis via targeting Wnt3 AND Runx2

Osteoporosis is defined as an aging-related skeletal disorder involving deterioration of bone mass and bone structure, and consequently, increased risk of fractures. Emerging evidence indicates the dysregulation of microRNAs (miRNAs) in the progression of osteoporosis. However, whether such associated miRNAs control osteoblast differentiation or constitute therapeutic targets remains elusive. In the present study, we found elevated circulating miR-374b-5p level associated with postmenopausal osteoporosis. miR-374b-5p served as a critical suppressor of osteoblast differentiation. We further identified that miR-374b-5p directly targeted Wnt family member 3 (Wnt3) and Runt-related transcription factor 2 (Runx2) through its 3'-untranslated regions (3'UTRs). Moreover, the antagonist of miR-374b-5p could promote bone formation in ovariectomy (OVX)-induced mice. Together, our results revealed that miR-374b-5p directly targeted Wnt3 and Runx2, negatively regulating osteoblast differentiation and bone formation. Collectively, circulating miR-374b-5p in the serum might serve as a potential diagnostic and therapeutic strategy for osteoporosis.

Asiatic acid attenuates hypertrophic and fibrotic differentiation of articular chondrocytes via AMPK/PI3K/AKT signaling pathway

Background

Osteoarthritis (OA), the most common joint disorder, is characterized by a progressive degradation of articular cartilage. Increasing evidence suggests that OA is closely associated with cartilage pathologies including chondrocyte hypertrophy and fibrosis.

Methods

In this study, we showed that asiatic acid (AA) treatment reduced chondrocyte hypertrophy and fibrosis. First, the cytotoxicity of AA (0, 5, 10, and 20 μM) to chondrocytes was evaluated, and 5 μM was selected for subsequent experiments. Then, we detected the gene and protein level of chondrocyte hypertrophic markers including type X collagen (COL-X), matrix metalloproteinase-13 (MMP-13), alkaline phosphatase (ALP), and runt-related transcription factor 2 (Runx2); chondrocyte fibrosis markers including type I collagen (COL-Ι) and alpha-smooth muscle actin (α-SMA); and chondrogenic markers including SRY-related HMG box 9 (SOX9), type II collagen (COL-II), and aggrecan (ACAN). Further, we tested the mechanism of AA on inhibiting chondrocyte hypertrophy and fibrosis. Finally, we verified the results in an anterior cruciate ligament transection (ACLT) rat OA model.

Results

We found that AA treatment inhibited the hypertrophic and fibrotic phenotype of chondrocytes, without affecting the chondrogenic phenotype. Moreover, we found that AA treatment activated AMP-activated protein kinase (AMPK) and inhibited phosphoinositide-3 kinase/protein kinase B (PI3K/AKT) signaling pathway in vitro. The results in an ACLT rat OA model also indicated that AA significantly attenuated chondrocyte hypertrophy and fibrosis.

Conclusion

AA treatment could reduce hypertrophic and fibrotic differentiation and maintain the chondrogenic phenotype of articular chondrocytes by targeting the AMPK/PI3K/AKT signaling pathway. Our study suggested that AA might be a prospective drug component that targets hypertrophic and fibrotic chondrocytes for OA treatment.

Identification of genetic loci associated with growth traits at weaning in yak through a genome-wide association study

A multilocus GWAS was performed to explore the genetic architecture of four growth traits in yak. In total, 354 female yaks for which measurements of body weight (BW), withers height (WH), body length (BL) and chest girth (CG) at weaning were available underwent genotyping with the Illumina BovineHD BeadChip (770K). After quality control, we retained 98 688 SNPs and 354 animals for GWAS analysis. We identified seven, 18, seven and nine SNPs (corresponding to seven, 17, seven and eight candidate genes) associated with BW, WH, BL and CG at weaning respectively. Interestingly, most of these candidate genes were reported to be involved in growth-related processes such as muscle formation, lipid deposition, feed efficiency, carcass composition and development of the central and peripheral nervous system. Our results offer novel insight into the molecular architecture underpinning yak growth traits. Further functional analyses are thus warranted to explore the molecular mechanisms whereby these genes affect these traits of interest.

Balance of Emission and Dynamical Controls on Ozone During the Korea-United States Air Quality Campaign From Multiconstituent Satellite Data Assimilation

Global multiconstituent concentration and emission fields obtained from the assimilation of the satellite retrievals of ozone, CO, NO2, HNO3, and SO2 from the Ozone Monitoring Instrument (OMI), Global Ozone Monitoring Experiment 2, Measurements of Pollution in the Troposphere, Microwave Limb Sounder, and Atmospheric Infrared Sounder (AIRS)/OMI are used to understand the processes controlling air pollution during the Korea-United States Air Quality (KORUS-AQ) campaign. Estimated emissions in South Korea were 0.42 Tg N for NO x and 1.1 Tg CO for CO, which were 40% and 83% higher, respectively, than the a priori bottom-up inventories, and increased mean ozone concentration by up to 7.5 ± 1.6 ppbv. The observed boundary layer ozone exceeded 90 ppbv over Seoul under stagnant phases, whereas it was approximately 60 ppbv during dynamical conditions given equivalent emissions. Chemical reanalysis showed that mean ozone concentration was persistently higher over Seoul (75.10 ± 7.6 ppbv) than the broader KORUS-AQ domain (70.5 ± 9.2 ppbv) at 700 hPa. Large bias reductions (>75%) in the free tropospheric OH show that multiple-species assimilation is critical for balanced tropospheric chemistry analysis and emissions. The assimilation performance was dependent on the particular phase. While the evaluation of data assimilation fields shows an improved agreement with aircraft measurements in ozone (to less than 5 ppbv biases), CO, NO2, SO2, PAN, and OH profiles, lower tropospheric ozone analysis error was largest at stagnant conditions, whereas the model errors were mostly removed by data assimilation under dynamic weather conditions. Assimilation of new AIRS/OMI ozone profiles allowed for additional error reductions, especially under dynamic weather conditions. Our results show the important balance of dynamics and emissions both on pollution and the chemical assimilation system performance.

Magnetic-Field Tuning of Light-Induced Superconductivity in Striped La_{2-x}Ba_{x}CuO_{4}

Optical excitation of stripe-ordered La_{2-x}Ba_{x}CuO_{4} has been shown to transiently enhance superconducting tunneling between the CuO_{2} planes. This effect was revealed by a blueshift, or by the appearance of a Josephson plasma resonance in the terahertz-frequency optical properties. Here, we show that this photoinduced state can be strengthened by the application of high external magnetic fields oriented along the c axis. For a 7 T field, we observe up to a tenfold enhancement in the transient interlayer phase correlation length, accompanied by a twofold increase in the relaxation time of the photoinduced state. These observations are highly surprising, since static magnetic fields suppress interlayer Josephson tunneling and stabilize stripe order at equilibrium. We interpret our data as an indication that optically enhanced interlayer coupling in La_{2-x}Ba_{x}CuO_{4} does not originate from a simple optical melting of stripes, as previously hypothesized. Rather, we speculate that the photoinduced state may emerge from activated tunneling between optically excited stripes in adjacent planes.

Prevalence of Helicobacter pylori infection and its association with lipid profiles

OBJECTIVE

To evaluate the prevalence of Helicobacter pylori (H. pylori, HP) infection in subjects receiving routine physical examination and its associations with age, sex, body mass index (BMI) and lipid profiles.

MATERIALS AND METHODS

Clinical information of 22,103 individuals who took routine physical examinations, including that on age, gender, height, weight, triglyceride, total cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol and data of HP infection were collected and analyzed.

RESULTS

H. pylori infection rate in 22,103 subjects taking routine physical examination was 44.5 %. More men tended to be infected with H. pylori than women (45.9 % vs 42.8 %; p < 0.01). The highest positive rate group was in the age group of 30-39 years (46.8 %) and the lowest rate was in the age group younger than 30 years (40.5 %). The obese had higher infection rate than the non-obese (p < 0.01). Mann-Whitney U test was used to explore the relationships between lipid profiles and H. pylori infection. There were significant associations among HDL, triglyceride and HP infection (p < 0.01). However, significant differences were not confirmed between cholesterol, LDL and H. pylori infection.

CONCLUSION

H. pylori infection was common among subjects receiving physical examination in Shanghai and it was most significantly associated with HDL and triglyceride, indicating that H. pylori might be a new cardiovascular risk factor (Tab. 3, Ref. 23).

[A systematic evaluation of the assessment methods of spasmoidc dysphonia]

To review the available subjective and objective evaluation methods used in the assessment of the spasmodic dysphonia.A systematic literature search was conducted in PubMed,web of science,EBSCO and Ovid database,date limited from 2000 to 2015,language limited English,using the following key words: "spasmodic dysphonia" OR "spastic dysphonia" AND "evaluat*" OR " diagnosis" OR "treatment" OR "assess*".Screening the titles and abstracts,and reading the full text,studies met the inclusion criteria were enrolled.The references of eligible publications were manually searched to identify additional studies.A total of 967 literatures were retrieved.Finally,twenty-three papers were enrolled in the study according to the inclusion criteria.Evaluation methods were mainly divided into subjective and objective,including perception,subjective self-assessment;and aerodynamic,acoustic analysis,respectively.The assessment of spasmodic dysphonia should be multidimensional.

CCAAT/enhancer binding protein beta protects muscle satellite cells from apoptosis after injury and in cancer cachexia

CCAAT/enhancer binding protein beta (C/EBPβ), a transcription factor expressed in muscle satellite cells (SCs), inhibits the myogenic program and is downregulated early in differentiation. In a conditional null model in which C/EBPβ expression is knocked down in paired box protein 7+ (Pax7+) SCs, cardiotoxin (CTX) injury is poorly repaired, although muscle regeneration is efficient in control littermates. While myoblasts lacking C/EBPβ can differentiate efficiently in culture, after CTX injury poor regeneration was attributed to a smaller than normal Pax7+ population, which was not due to a failure of SCs to proliferate. Rather, the percentage of apoptotic SCs was increased in muscle lacking C/EBPβ. Given that an injury induced by BaCl₂ is repaired with greater efficiency than controls in the absence of C/EBPβ, we investigated the inflammatory response following BaCl₂ and CTX injury and found that the levels of interleukin-1β (IL-1β), a proinflammatory cytokine, were robustly elevated following CTX injury and could induce C/EBPβ expression in myoblasts. High levels of C/EBPβ expression in myoblasts correlated with resistance to apoptotic stimuli, while its loss increased sensitivity to thapsigargin-induced cell death. Using cancer cachexia as a model for chronic inflammation, we found that C/EBPβ expression was increased in SCs and myoblasts of tumor-bearing cachectic animals. Further, in cachectic conditional knockout animals lacking C/EBPβ in Pax7+ cells, the SC compartment was reduced because of increased apoptosis, and regeneration was impaired. Our findings indicate that the stimulation of C/EBPβ expression by IL-1β following muscle injury and in cancer cachexia acts to promote SC survival, and is therefore a protective mechanism for SCs and myoblasts in the face of inflammation.

Evaluation of common variants in CNR2 gene for bone mineral density and osteoporosis susceptibility in postmenopausal women of Han Chinese

Postmenopausal osteoporosis is a major health problem with important genetic factors in postmenopausal women. We thoroughly evaluated the relationship of CNR2 polymorphisms with osteoporosis in a cohort of 1032 osteoporosis patients and 2089 healthy controls from Han Chinese postmenopausal women. Statistically significant differences, depending on different genotypes, were presented.

INTRODUCTION

Osteoporosis is a major health problem in postmenopausal women, which is a multifactorial disease in which genetic determinants are modulated by hormonal, environmental, and nutritional factors. An important clinical risk factor in the pathogenesis of osteoporosis is the presence of genetic polymorphism in susceptibility genes. The aim of our study was to investigate whether CNR2 gene, which attributes to osteoporosis susceptibility in some populations, is associated with bone mineral density (BMD) or osteoporosis in Han Chinese postmenopausal women.

METHODS

We examine 39 SNPs covering the region of CNR2 gene in 3121 Han Chinese postmenopausal women, consisting of 1032 osteoporosis patients and 2089 healthy controls, to evaluate the association with BMD and osteoporosis.

RESULTS

We found that rs4237 and rs2501431 were significantly associated with BMD and osteoporosis (corrected p = 0.020085 and 0.017199) in our sample, and the TT genotype of rs2501431 and the AA genotype of rs4237 had lower lumbar spine BMD and femoral neck BMD compared with the other genotypes. Additionally, analyses by haplotypes indicated that two haplotype blocks, containing rs4237 and rs2501431 respectively, in the CNR2 gene significantly associated with BMD and osteoporosis (both global permutation p < 0.001), and a risk haplotype (ATTT) in the block of rs3003336-rs2501431-rs2502992-rs2501432 had almost 4-fold increase in the cases.

CONCLUSIONS

Our results provide further supportive evidence for an important role of CNR2 gene in the etiology of osteoporosis and suggest that it may be a genetic risk factor for BMD and osteoporosis in Han Chinese postmenopausal women.