Genetic effects and causal association analyses of 14 common conditions/diseases in multimorbidity patterns.

BACKGROUND: Multimorbidity has become an important health challenge in the aging population. Accumulated evidence has shown that multimorbidity has complex association patterns, but the further mechanisms underlying the association patterns are largely unknown. METHODS: Summary statistics of 14 conditions/diseases were available from the genome-wide association study (GWAS). Linkage disequilibrium score regression analysis (LDSC) was applied to estimate the genetic correlations. Pleiotropic SNPs between two genetically correlated traits were detected using pleiotropic analysis under the composite null hypothesis (PLACO). PLACO-identified SNPs were mapped to genes by Functional Mapping and Annotation of Genome-Wide Association Studies (FUMA), and gene set enrichment analysis and tissue differential expression were performed for the pleiotropic genes. Two-sample Mendelian randomization analyses assessed the bidirectional causality between conditions/diseases. RESULTS: LDSC analyses revealed the genetic correlations for 20 pairs based on different two-disease combinations of 14 conditions/diseases, and genetic correlations for 10 pairs were significant after Bonferroni adjustment (P<0.05/91 = 5.49E-04). Significant pleiotropic SNPs were detected for 11 pairs of correlated conditions/diseases. The corresponding pleiotropic genes were differentially expressed in the brain, nerves, heart, and blood vessels and enriched in gluconeogenesis and drug metabolism, biotransformation, and neurons. Comprehensive causal analyses showed strong causality between hypertension, stroke, and high cholesterol, which drive the development of multiple diseases. CONCLUSIONS: This study highlighted the complex mechanisms underlying the association patterns that include the shared genetic components and causal effects among the 14 conditions/diseases. These findings have important implications for guiding the early diagnosis, management, and treatment of comorbidities.

PKM2 is a Novel Osteoporosis-Associated Protein in Chinese.

Purpose:Osteoporosis is characterized by low bone mineral density (BMD) and high risk of osteoporotic fracture (OF). Peripheral blood monocytes (PBM) can differentiate into osteoclasts to resorb bone. This study was to identify PBM-expressed proteins significant for osteoporosis in Chinese Han elderly population (>65 years), and focused on two phenotypes of osteoporosis: low BMD and OF. METHODS: Label-free quantitative proteomics was employed to profile PBM proteome and to identify differentially expressed proteins (DEPs) between OF (N=27) vs. non-fractured (NF, N=24) subjects and between low BMD (N=12) vs. high BMD (N=12) subjects in women. Western blotting (WB) was conducted to validate differential expression, and ELISA to evaluate translational value for secretory protein of interest. RESULTS: We discovered 59 DEPs with fold change (FC)>1.3 (P<1×10-5), and validated the significant up-regulation of pyruvate kinase isozyme 2 (PKM2) with osteoporosis (P<0.001). PKM2 protein upregulation with OF was replicated with PBM in men (P=0.04). Plasma PKM2 protein level was significantly elevated with OF in an independent sample (N=100, FC=1.68, P=0.01). Pursuant functional assays showed that extracellular PKM2 protein supplement not only promoted monocyte trans-endothelial migration, growth, and osteoclast differentiation (marker gene expression), but also inhibited osteoblast growth, differentiation (ALP gene expression), and activity. CONCLUSION: The above findings suggest that PKM2 protein is a novel osteoporosis-associated functional protein in Chinese Han elderly population. It may serve as a risk biomarker and drug target for osteoporosis.

Establishment and implementation of a nurse-led interdisciplinary management strategy for central line maintenance: A single-center experience.

Objectives: This study aimed to establish and implement an interdisciplinary management strategy led by senior nurses via a vascular access specialist team (VAST) at a teaching hospital. Methods: In 2021, the hospital established and implemented a nurse-led VAST management strategy to improve the quality of clinical central line maintenance. The VAST comprised senior nurses specialized in intravenous therapy, ultrasound/radiology technologists, medical doctors with central venous catheterization certificates, central line maintenance nurses, and administrative coordinators. The management strategy mainly included systemic on-the-job training for VAST members, the establishment of an interdisciplinary central line emergency "green channel," the formation of a VAST-based, nurse-led standardized clinical rounding system, and the standardization of central line self-care instructions for patients. During the pre- (July 2020 to April 2021) and post- (May 2021 to May 2022) of the implementation the interdisciplinary management strategy, overall patients' self-care ability, the success rate of catheterization at first time, central line management compliance rate, and patients' satisfaction with catheter maintenance were investigated and compared. Results: The results showed the score self-care ability was increased from 74.75 ± 18.4 (pre-VAST) to 99.10 ± 23.65 (post- VAST); the success rate for catheterization at first time was improved to 100% (225/225), compared to 92.9% (209/225) at pre-VAST; the central line management compliance rate was also increased to 99.6% (224/225) at post-VAST from 93.3% (210/225) at pre-VAST. A patient satisfaction survey on catheter maintenance showed improvements in all five indicators were compared to the pre- VAST (P < 0.05). Conclusions: The nurse-led VAST interdisciplinary strategy can effectively improve the quality of clinical central line management and should be used to reinforce clinical catheterization and maintenance of central lines.

Plasma gelsolin is associated with hip BMD in Chinese postmenopausal women.

Gelsolin (GSN) protein, expressed in circulating monocytes, was previously reported to be associated with osteoporosis in both Chinese and Caucasian women. This study aims to test if plasma GSN protein level is associated with hip bone mineral density (BMD) in Chinese population. Based on two study Groups containing 6,308 old Chinese, we adopted extreme sampling scheme and selected 3 independent samples (Subgroups 1-3) for discovery, replication, and validation purposes. We tested plasma GSN concentration, and analyzed whether plasma GSN level differs between subjects with extremely low vs. high hip BMD. In Group 1 (N = 1,860), the plasma GSN level increased in the female with low BMD, which was discovered in the Subgroup 1 (N = 42, p = 0.093) and replicated in the Subgroup 2 (N = 39, p = 0.095). With more extreme sampling for the Subgroup 3 from the Group 2 (N = 4,448), the difference of plasma GSN level in the female with low BMD vs. high BMD is more significant (N = 45, p = 0.037). After the subjects were pooled from Subgroups 2 and 3, the difference in plasma GSN between low and high BMD subjects became even more significant (p = 0.016). The plasma GSN level was negatively correlated with total hip BMD (r = -0.26, p = 0.033). We concluded that plasma GSN was associated with hip BMD in Chinese postmenopausal women and plasma GSN might be a potential risk biomarker for osteoporosis.

Association of Plasma Irisin with Bone Mineral Density in a Large Chinese Population Using an Extreme Sampling Design.

Irisin, a myokine produced by skeletal muscle in response to physical exercise, promotes trans-differentiation of white adipose tissue into brown adipose tissue. Recent evidences suggested that irisin also plays an important role in the control of bone metabolism. This study aimed to ascertain the relationship between plasma irisin and bone mineral density (BMD) in Chinese population by adoption of an extreme sampling method. Based on a large and screened Chinese elderly population (N = 6308), two subgroups with extremely high and low hip BMD were selected for discovery (N = 80, high vs. low BMD = 44:36) and validation (N = 60, high vs. low BMD = 30:30), respectively. Plasma irisin, P1NP, and ß-CTx were measured using commercially available ELISA kits. Other metabolic parameters (e.g., blood glucose, total cholesterol and triglycerides) were collected. Student's t test and Spearman correlation analyses were conducted in SPSS. Significant difference was discovered for plasma irisin between females and age-matched males (N = 80, male vs. female = 42:38, P = 0.002). The plasma irisin levels were significantly higher in high BMD subjects than in low BMD subjects, which was observed in both discovery (P = 0.012) and validation samples (P = 0.022). However, such observation was limited to males only. Further correlation analyses in males showed that plasma irisin was correlated with BMD (r = 0.362, P = 0.025) and triglyceride (r = - 0.354, P = 0.032). Plasma irisin levels were associated with hip BMD in Chinese elderly men. This study represented the first effort of investigating the relationship of plasma irisin and BMD in elderly population. The positive correlation between plasma irisin and BMD hints intrinsic communication between muscle and bone.

[A few questions on the major collateral of stomach].

It is held by some of the researches that the "16 collaterals" is composed of the "15 collaterals" and "the major collateral of stomach". And it is included into the textbook that Xuli, the major collateral of stomach, is the pulsation point at the cardiac region. Xuli is often explained as the empty portion of the human body by many researches. Through analysis and summarization of the related theory of the major collateral of stomach, the above mentioned opinion is discussed. And the understanding on the major collateral of stomach is deepened. As a result, it is concluded that count the major collateral of stomach into the 16 collaterals together with the 15 collaterals is inadvisable. The real pulsation point at the cardiac region locates under the left breast. And the real meaning of Xuli is "extending in all directions".

Effects of nerve growth factor on N-methyl-D-asparate receptor 1 after spinal cord injury in rats.

OBJECTIVE: To explore the effects of the nerve growth factor (NGF) on N-methyl-D-asparate receptor 1 (NMDAR 1) after spinal cord injury. METHODS: Spinal cord injury of Wistar rats was performed with Allen's method by a 10 gx2.5 cm impact on the posterior T8 spinal cord. NGF was given to the rats of the treatment group via subarachnoid space tube at once, 2, 4, 8, 12 and 24 hours after spinal cord injury, respectively. The expression of NMDAR1 mRNA in spinal cord was detected by in situ hybridization. RESULTS: Rare expression sequence of NMDAR1 mRNA was found in rat spinal cord of the normal group. A strong expression sequence of NMDAR1 mRNA was found in rat spinal cord of the normal saline group. The expression of NMDAR1 mRNA in the NGF group was significantly decreased as compared with that in the normal saline group (P=0.01). CONCLUSIONS: NGF can relieve damage of injured spinal cord by prohibiting the expression of NMDAR1 mRNA.

Effect of nerve growth factor on neuronal apoptosis after spinal cord injury in rats.

OBJECTIVE: To explore the molecular mechanism of the protective effect of nerve growth factor (NGF) on injured spinal cord. METHODS: The posterior T(8) (the 8th thoracic segment) spinal cords of 60 Wistar rats were injured by impacts caused by objects (weighing 10 g) falling from a height of 2.5 cm with Allen's way. Solution with nerve growth factors (NGF) was given to 30 rats (the NGF group) through a microtubule inserted into the subarachnoid cavity immediately, and at 2, 4, 8, 12 and 24 hours after spinal cord injury (SCI) respectively. Normal saline (NS) with same volume was given to the other 30 rats (the NS group) with the same method. And 5 normal rats were taken as the normal controls. The expression of bcl-2 and bax proteins in spinal cord was detected with immunohistochemistry. The apoptotic neurons in spinal cord were measured with terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling of DNA fragments (TUNEL) staining. RESULTS: The positive expression of bcl-2 protein was strong in the normal controls, but decreased in the NS group, and increased significantly in the NGF group as compared with that of the NS group (P<0.01). The positive expression of bax protein was also strong in the normal controls, but increased in the NS group, and decreased significantly in the NGF group as compared with that of the NS group (P<0.01). Apoptotic neurons were found in the NS group, and they decreased significantly in the NGF group as compared with that of the NS group (P<0.01). CONCLUSIONS: NGF can protect the injured nerve tissues through stimulating the expression of bcl-2 protein, inhibiting the expression of bax protein and inhibiting the neuronal apoptosis after SCI.

Effects of nerve growth factor on neuronal nitric oxide production after spinal cord injury in rats.

OBJECTIVE: To explore the protective effects of nerve growth factor (NGF) on injured spinal cord. METHODS: The spinal cord injury (SCI) model of Wistar rats was established by a 10 gx2.5 cm impact force on the T(8) spinal cord. NGF (60 microg/20 microl) was given to the rats of the treatment group immediately and at 2, 4, 8, 12, 24 hours after SCI. The level of neuronal constitutive nitric oxide synthase (ncNOS) and the expression of ncNOS mRNA in the spinal cord were detected by the immunohistochemistry assay and in situ hybridization method. RESULTS: Abnormal expression of ncNOS was detected in the spinal ventral horn motorneuron in injured rats. The levels of ncNOS protein in the NGF group were significantly lower than those in the normal saline group (P<0.05 ). The ncNOS mRNA expression was found in the spinal ventral horn motorneuron in injured rats and the expression in the NGF group was significantly decreased compared with that in the normal saline group (P<<0.01). CONCLUSIONS: NGF can protect the injured tissue of the spinal cord by prohibiting abnormal expression of nitric oxide synthase and the neurotoxicity of nitric oxide.