Anatomical structure of the coracohumeral ligament and its effect on shoulder joint stability

BACKGROUND

In this study, coracohumeral ligament (CHL) specimens were carefully dissected to observe its length, width, thickness and tension at different positions of the shoulder joint, thereby elucidating its effects on shoulder joint stability.

MATERIALS AND METHODS

Fresh frozen shoulder joints from 40 normal adult cadaveric specimens were dissected to reveal the CHL. With the shoulder joints placed at different positions, the length of the CHL and the width and thickness of the middle part of the ligament were measured. The changes in tension of the CHL were also observed. When the shoulder joint maintained the neutral position, the length of the CHL was 52.23 ± 1.02 mm and the width and thickness of the middle part of the ligament were 15.95 ± 0.59 mm and 1.46 ± 0.06 mm, respectively.

RESULTS

When the shoulder joint moved from the neutral position to 90° external rotation, from the neutral position to 30° adduction or from the neutral position to 30° flexion/extension or when the shoulder joint is pulled down with a 5 kg weight, the CHL was elongated and thinned, maintaining a strained state. When the shoulder joint moved from the neutral position to 90° internal rotation, from the neutral position to 90° abduction or from the neutral position to 30° flexion/ extension, the CHL was shortened and thickened, maintaining a relaxed state.

CONCLUSIONS

The CHL may limit the external rotation, adduction and downward movement of the shoulder joint and the process from the neutral position to the 30° flexion/extension, maintaining shoulder joint stability.

Association of polymorphisms in intron 2 of FGFR2 and breast cancer risk in Сhinese women

Recent genome-wide association studies (GWAS) demonstrated that genetic variation in intron 2 of fibroblast growth factor receptor 2 (FGFR2) was a novel risk for breast cancer. We investigated whether two SNPs rs1219648 and rs2981582 in intron 2 of FGFR2 were associated with the risk of breast cancer in Chinese women. A total of 340 female breast cancer patients and 400 normal age-matched controls were recruited. Two SNPs were genotyped using matrix-assisted laser desorption/ionization mass spectrometry. The two SNPs rs1219648 and rs2981582 showed no association with the risk of breast cancer. A subgroup analysis by menopausal status demonstrated that the distribution of rs2981582 T alleles, including CT and TT genotypes, was significantly higher in premenopausal patients compared with postmenopausal patients. The TT genotype in rs2981582 was more strongly associated with ER-positive than with ER-negative tumors by ER status analysis. Analysis by haplotypes showed that no haplotypes associated with breast cancer. The results showed no association between two SNPs, rs1219648 and rs2981582 and breast cancer risk, although in a stratified analysis rs2981582 strongly associated with premenopausal and ER-positive breast cancer patients in Chinese women.

Association of C1q Binding Status With De Novo HLA Antibody Clinical Features and Allograft Function in Kidney Transplantation Patients During Eight Years of Dynamic Follow-up

BACKGROUND

C1q-binding donor-specific antibody (DSA) is detrimental to transplanted kidney function. However, the factors that affect C1q binding status are unclear.

METHODS

A total of 519 samples from 129 consecutive kidney transplantation patients during 8 years of dynamic follow-up were collected for HLA antibody (Ab) screening and C1q detection.

RESULTS

Among the detected HLA Abs, the majority were class II, and the DQ subtypes composed the highest proportion. The C1q-binding Abs were all HLA-II, and the DQ subtypes had the highest rate of C1q positivity. With a cutoff mean fluorescence intensity (MFI) value of 7349, the sensitivity and specificity of detecting C1q-binding Abs from all HLA-II Abs were 84.48% and 83.56%, respectively. Additionally, C1q is more likely to be bound by DSA than non-donor-specific antibody (NDSA). Compared with free DSA/NDSA, the MFI values of C1q-binding DSA/NDSA are more closely correlated with serum creatinine levels and reflect the effect of anti-antibody-mediated rejection treatment more sensitively.

CONCLUSIONS

HLA-II Abs (particularly DQ subtypes), high titers of Abs, and DSA are important relevant factors of C1q positivity. The MFI value of C1q-binding DSA may be a useful clinical indicator of HLA antibody-mediated graft injury before the appearance of histologically typical humoral rejection.

The Effectiveness of hCG and LHRH in Boys with Cryptorchidism: A Meta-Analysis of Randomized Controlled Trials

To systematically review the efficacy of hCG and LHRH on testicular descent in boys with cryptorchidism, comprehensive search was performed to identify randomized controlled trials (RCTs) in PubMed, EMBASE, the Cochrane Library, Wanfang Database, and China National Knowledge Infrastructure (CNKI) up to March 2014. Outcomes included testicular complete descent rate (TCDR) and cure rate of patients. Study quality was evaluated using the Jadad scale. Meta-analysis was performed using Review Manager software. Finally, 13 studies were included. hCG and LHRH increased TCDR comparing with control group. The success rate of hCG and LHRH was 24 and 19%, respectively. Further, hCG and LHRH had significant effect on bilateral cryptorchidism, but not on unilateral cryptorchidism. All side effects were transitory and not severe, but if they have long-term harms were not clear. hCG and LHRH can effectively increase TCDR and there was no significant difference between them. However, the hormones cannot be recommended for everyone because of their low success rates and potential long-term harms. Further studies are needed to determine the efficacy of hormonal treatment for subtypes of cryptorchidism.

Pdcd4 restrains the self-renewal and white-to-beige transdifferentiation of adipose-derived stem cells

The stemness maintenance of adipose-derived stem cells (ADSCs) is important for adipose homeostasis and energy balance. Programmed cell death 4 (Pdcd4) has been demonstrated to be involved in the development of obesity, but its possible roles in ADSC function and adipogenic capacity remain unclear. In this study, we demonstrate that Pdcd4 is a key controller that limits the self-renewal and white-to-beige transdifferentiation of ADSCs. Pdcd4 deficiency in mice caused stemness enhancement of ADSCs as evidenced by increased expression of CD105, CD90, Nanog and Oct4 on ADSCs, together with enhanced in situ proliferation in adipose tissues. Pdcd4 deficiency promoted proliferation, colony formation of ADSCs and drove more ADSCs entering the S phase accompanied by AKT activation and cyclinD1 upregulation. Blockade of AKT signaling in Pdcd4-deficient ADSCs led to a marked decline in cyclinD1, S-phase entry and cell proliferation, revealing AKT as a target for repressing ADSC self-renewal by Pdcd4. Intriguingly, depletion of Pdcd4 promoted the transdifferentiation of ADSCs into beige adipocytes. A reduction in lipid contents and expression levels of white adipocyte markers including C/EBPα, PPAR-γ, adiponectin and αP2 was detected in Pdcd4-deficient ADSCs during white adipogenic differentiation, substituted by typical beige adipocyte characteristics including small, multilocular lipid droplets and UCP1 expression. More lactate produced by Pdcd4-deficient ADSCs might be an important contributor to the expression of UCP1 and white-to-beige transdifferentiation. In addition, an elevation of UCP1 expression was confirmed in white adipose tissues from Pdcd4-deficient mice upon high-fat diet, which displayed increased energy expenditure and resistance to obesity as compared with wild-type obese mice. These findings provide evidences that Pdcd4 produces unfavorable influences on ADSC stemness, which contribute to adipose dysfunction, obesity and metabolic syndromes, thereby proposing Pdcd4 as a potential intervening target for regulating ADSC function.

Surface Collective Modes in the Topological Insulators Bi_{2}Se_{3} and Bi_{0.5}Sb_{1.5}Te_{3-x}Se_{x}

We used low-energy, momentum-resolved inelastic electron scattering to study surface collective modes of the three-dimensional topological insulators Bi_{2}Se_{3} and Bi_{0.5}Sb_{1.5}Te_{3-x}Se_{x}. Our goal was to identify the "spin plasmon" predicted by Raghu and co-workers [Phys. Rev. Lett. 104, 116401 (2010)]. Instead, we found that the primary collective mode is a surface plasmon arising from the bulk, free carriers in these materials. This excitation dominates the spectral weight in the bosonic function of the surface χ^{"}(q,ω) at THz energy scales, and is the most likely origin of a quasiparticle dispersion kink observed in previous photoemission experiments. Our study suggests that the spin plasmon may mix with this other surface mode, calling for a more nuanced understanding of optical experiments in which the spin plasmon is reported to play a role.

Polarization-resolved spectroscopy imaging of grain boundaries and optical excitations in crystalline organic thin films

Exploration of optical properties of organic crystalline semiconductors thin films is challenging due to submicron grain sizes and the presence of numerous structural defects, disorder and grain boundaries. Here we report on the results of combined linear dichroism (LD)/ polarization-resolved photoluminescence (PL) scanning microscopy experiments that simultaneously probe the excitonic radiative recombination and the molecular ordering in solution-processed metal-free phthalocyanine crystalline thin films with macroscopic grain sizes. LD/PL images reveal the relative orientation of the singlet exciton transition dipoles at the grain boundaries and the presence of a localized electronic state that acts like a barrier for exciton diffusion across the grain boundary. We also show how this energy barrier can be entirely eliminated through the optimization of deposition parameters that results in films with large grain sizes and small-angle boundaries. These studies open an avenue for exploring the influence of long-range order on exciton diffusion and carrier transport.

In-depth understanding of organic crystalline semiconductor thin films is critical for the development of many electronic and photonic devices. Here, the authors use combined linear dichroism and polarization-resolved photoluminescence scanning microscopy to unveil the nature of excited states in such systems.

Abstract 1729: Discovery of a synthetic small molecule inhibitor of HSP90 for cancer therapy

HSP90 is a major heat shock protein involved in the proper folding of its client proteins including many onco-proteins. HSP90 is elevated in tumor cells with a more active configuration, making it a potential target for cancer drug development. Utilizing structure-base design, we discovered a small molecule compound that inhibits HSP90 activity with an IC50 at low- nanomolar concentration. Cell proliferation was inhibited by this compound at a IC50 of single-digit nanomolar concentration across many different cancer cell lines. Mechanism of action studies demonstrated that this compound could induce HER-2 degradation in the breast cancer cell line BT-474 in vitro at concentrations between 100-300 nM. The compound showed an ideal pharmacological kinetic feature of less exposure and fast clearance in rat retina after intravenous administration, thus reducing the possibility of ocular toxicity as demonstrated by some other earlier HSP90 inhibitors. The compound also caused tumor growth inhibition in the xenograft tumor models, correlating with its target inhibition activity in these tumors. These data supports further development of this compound as a cancer therapeutic agent.

Citation Format: Rudi Bao, Zhongzong Pan, Zhiming Zhao, Hongping Yu, Yaochang Xu. Discovery of a synthetic small molecule inhibitor of HSP90 for cancer therapy. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1729. doi:10.1158/1538-7445.AM2015-1729

Abstract 797: Discovery of a highly selective and potent small molecule inhibitor against c-MET for cancer therapy

c-MET is a receptor tyrosine kinase that is dysregulated in several types of maliganacies, including gastric, liver and lung cancers. Abnormal activation of c-MET could be caused by gene amplification, overexpression, or HGF aberrant expression. Activation of c-MET is involved in several cellular processes, including cell proliferation, cell migration, and angiogenesis. To explore c-MET targeted therapy, we discovered a small molecule that selectively inhibits c-MET activity with an IC50 of single digit nanomolar concentration across several cell lines. In xenograft tumor models from cell lines harboring cMET amplification including liver, gastric and lung cancer, tumor growth was significantly inhibited by this compound in a dose dependent manner. In addition, PD studies showed that c-MET and down-stream signaling pathways were blocked by the compound in the cMET amplified tumors. The compound also showed desirable PK and safety profiles. These data warrants further development of this compound for cancer therapy in cMET dysregulated cancers.

Citation Format: Rudi Bao, Zhongzong Pan, Zhiming Zhao, Hongping Yu, Yaochang Xu. Discovery of a highly selective and potent small molecule inhibitor against c-MET for cancer therapy. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 797. doi:10.1158/1538-7445.AM2015-797

Peroxisome proliferator-activated receptorβ/δ activation is essential for modulating p-Foxo1/Foxo1 status in functional insulin-positive cell differentiation

Peroxisome proliferator-activated receptors (PPARs) participate in energy homeostasis and play essential roles in diabetes therapy through their effects on non-pancreas tissues. Pathological microenvironment may influence the metabolic requirements for the maintenance of stem cell differentiation. Accordingly, understanding the mechanisms of PPARs on pancreatic β-cell differentiation may be helpful to find the underlying targets of disrupted energy homeostasis under the pancreatic disease condition. PPARs are involved in stem cell differentiation via mitochondrial oxidative phosphorylation, but the subtype member activation and the downstream regulation in functional insulin-positive (INS⁺) cell differentiation remain unclear. Here, we show a novel role of PPARβ/δ activation in determining INS⁺ cell differentiation and functional maturation. We found PPARβ/δ expression selectively upregulated in mouse embryonic pancreases or stem cells-derived INS⁺ cells at the pancreatic mature stage in vivo and in vitro. Strikingly, given the inefficiency of generating INS⁺ cells in vitro, PPARβ/δ activation displayed increasing mouse and human ES cell-derived INS⁺ cell numbers and insulin secretion. This phenomenon was closely associated with the forkhead box protein O1 (Foxo1) nuclear shuttling, which was dependent on PPARβ/δ downstream PI3K/Akt signaling transduction. The present study reveals the essential role of PPARβ/δ activation on p-Foxo1/Foxo1 status, and in turn, determining INS⁺ cell generation and insulin secretion via affecting pancreatic and duodenal homeobox-1 expression. The results demonstrate the underlying mechanism by which PPARβ/δ activation promotes functional INS⁺ cell differentiation. It also provides potential targets for anti-diabetes drug discovery and hopeful clinical applications in human cell therapy.

Placental miR-106a∼363 cluster is dysregulated in preeclamptic placenta

Preeclampsia (PE) is the leading cause of maternal and perinatal mortality and morbidity. MicroRNAs are strongly implicated in the pathogenesis of this syndrome. In current study, we performed a microarray assay to explore miRNA expression profile in the placenta, and found 11 upregulated and 7 downregulated miRNAs in preeclampsia. miR-363, plus other 5 member of miR-106a∼363 cluster was further examined and validated. These findings would facilitate further investigation of aberrant expression of miRNAs in the pathology of preeclampsia.

Polymorphisms in the TNF-α, TNFR1 gene and risk of rheumatoid arthritis in Chinese Han population

Recent advances have highlighted a major genetic contribution to the pathogenesis of rheumatoid arthritis (RA).The aim of this study was to investigate whether polymorphisms of TNF-α (rs1800630, rs1800629) and TNFR1 (rs767455) were associated with susceptibility to and clinical outcome of RA in Chinese Han population. The target gene polymorphisms were genotyped in 256 patients with RA and 331 healthy controls using a high resolution melting (HRM) method. ESR, CRP, RF anti-CCP and anti-GPI level were also assayed and compared in genotypes of each polymorphism. Significant difference was observed in the genotype distributions and allele frequencies of TNF-α rs1800629 (P = 0.001, P < 0.001, respectively) between patients with RA and controls. There is no evidence to suggest an association between genotypes of the 3 SNPs according to age, gender, disease duration, DAS28 and serum level of autoantibodies. This study identifies a potentially important role for TNF-α rs1800629 polymorphisms in the susceptibility to RA.However, further studies in larger cohorts are required.

Circulating chemerin levels are increased in first-degree relatives of type 2 diabetic patients

BACKGROUND

Chemerin is an important risk factor of insulin resistance and metabolic syndrome. The aim of this study was to explore the potential role of chemerin in the early stage of diabetes development.

METHODS

63 control subjects without any family history of diabetes and with normal glucose tolerance (NGT) and 74 healthy, first-degree relatives (FDRs) of type 2 diabetic patients were recruited in the study. All subjects underwent a 75 g oral glucose tolerance (OGTT) test after having fasted overnight. Plasma glucose, insulin, total cholesterol, HDL cholesterol, triglycerides, chemerin, and adiponectin were measured.

RESULTS

FDR subjects had higher BMI, WHR, waist, fasting plasma glucose, fasting insulin, TG, UA, HOMA-IR, LDL-C, and lower HDL- C levels than control subjects (p < 0.05). The FDRs group had significantly lower adiponectin levels while chemerin was higher. Plasma chemerin levels were independently correlated with HOMA-IR, FINS, TG, FPG, and adiponectin level. Multiple stepwise regression analysis showed that HOMA-IR and TG were independent risk factors that influenced circulating chemerin levels.

CONCLUSIONS

These findings showed a significant increase of chemerin levels in FDR subjects which suggested that chemerin may be involved in the development and progression of insulin resistance.