Atrial natriuretic peptide protects vertebral endplate chondrocytes against H2O2‑induced apoptosis and oxidative stress through activation of the Nrf2/HO‑1 signaling pathway

The present study aimed to investigate the effect of atrial natriuretic peptide (ANP) on cell apoptosis and oxidative stress in H₂O₂-induced vertebral endplate chondrocytes (EPCs), and to assess the associated mechanisms involved. Cell viability and apoptosis were evaluated using the Cell Counting Kit-8 method and TUNEL assay, respectively. In addition, the scavenging capability was detected using various enzymatic assays, and the quantity of nitric oxide (NO) and malondialdehyde (MDA), and activity of superoxide dismutase (SOD) were assessed. The expression levels of apoptosis-related proteins, activation of the nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling pathway induced by H₂O₂ and the effect of treatment with ANP on vertebral EPCs were detected by western blotting. The results revealed that ANP protected EPCs from H₂O₂-induced cell damage. H₂O₂-induced intracellular MDA was decreased by ANP, and the levels of SOD and NO were increased in the presence of ANP. ANP also inhibited the H₂O₂-induced alterations in the expression levels of cleaved-caspase-3, Bax and Bcl-2. Finally, ANP blocked H₂O₂-induced oxidative stress through activating the Nrf2/HO-1 signaling pathway. These findings suggested that ANP may effectively protect EPCs through inhibition of H₂O₂-induced oxidant injury and cell death by activating the Nrf2/HO-1 signaling pathway.

[A preliminary investigation of the clinical characteristics of community acquired pneumonia with concomitant pulmonary embolism]

Objective: To understanding the clinical characteristics of the patients of pneumonia concomitant with acute pulmonary embolism, and the early identification of high-risk patients. Methods: Retrospective analysis of hospitalized patients with confirmed diagnosis of community acquired pneumonia (CAP) with concomitant pulmonary embolism (PE) within a period of 5 years. Patients hospitalized with CAP alone in the same period were included in the control group in a ratio of 1∶2 according to the principle of gender and age. The demographic characteristics, clinical feature, laboratory examination, radiographic and other clinical data of these 2 groups of patients were studied. Statistical analysis was performed by Chi-square test, Kruskal-Wallis test and logistic regression. Results: Thirty-nine patients with CAP combined with PE and 78 patients with CAP alone were included. Compared to patients with CAP alone, dyspnea (21/39 vs 21/78, P=0.004), a history of heart disease (10/39 vs 8/78, P=0.031), and a history of connective tissue diseases (3/39 vs 0/78, P=0.035) were more common to seen in patients with CAP combined with PE. D-dimer [2 222(854, 3 539) ng/ml vs 295(168, 707) ng/ml, P=0.000], arterial PH value (7.5±0.5 vs 7.4±0.4, P=0.022), BNP [103.9(48.7, 236.8) pg/ml vs 98.4(44.8, 246.3) pg/ml, P=0.028] and incidence of lower extremity venous thrombosis (18/39 vs 3/41, P=0.000) were higher in patients with CAP combined with PE, while arterial partial pressure of CO₂ [(35.3±6.2) mmHg vs (38.4±4.4) mmHg, P=0.009, 1 mmHg=0.133 kPa] was lower. Logistic regression analysis showed that D-dimer (P=0.000) and dyspnea (P=0.033) were associated with the risk of PE. Conclusion: When patients with CAP represent dyspnea or have a history of heart disease or connective tissue diseases concomitant PE should be considered for differential diagnosis. Determination of D-dimer, arterial PH value, arterial partial pressure of CO₂, BNP and ultrasonography of lower extremities had important implications for the diagnosis of pneumonia complicated with acute pulmonary embolism.

Identifying Risks for Persistent Postconcussive Symptoms in a Pediatric Emergency Department: An Examination of a Clinical Risk Score

OBJECTIVE

External examination of a clinical risk score to predict persistent postconcussive symptoms (PPCS) in a pediatric emergency department (ED).

METHODS

Prospective cohort study of 5- to 18-year-old patients diagnosed with an acute concussion. Risk factors were collected at diagnosis and participants (n = 85) were followed to determine PPCS 30 days postinjury. Univariate logistic regression analyses were completed to examine associations of risk factors with PPCS.

RESULTS

Headache and total clinical risk score were associated with increased odds of PPCS in the univariate analyses, OR 3.37 (95% CI 1.02, 11.10) and OR 1.25 (95% CI 1.02, 1.52), respectively. Additionally, teenage age group, history of prolonged concussions, and risk group trended toward association with PPCS, OR 4.79 (95% CI 0.93, 24.7), OR 3.41 (95% CI 0.88, 13.20), and OR 2.23 (95% CI 0.88, 5.66), respectively.

CONCLUSION

Our study supports the use of multiple variables of a clinical risk score to assist with ED risk stratification for pediatric patients at risk for PPCS.

[Experimental study of local administration of silver nanoparticles for the treatment of pyogenic spondylitis]

OBJECTIVE

To establish a proper animal model of pyogenic spondylitis, to evaluate the efficacy of silver nanoparticles for treatment of spinal pyogenic infections, and to explore the distribution of the particles in the body of the animals.

METHODS

Staphylococcus aureus was inoculated into intervertebral discs of rabbits to establish a spinal pyogenic infection model. These rabbits were divided into Group A [0.1 mg/(kg.d)], Group B [1 mg/(kg.d)], and a Control group. Groups A and B were injected with different doses of silver nanoparticles solution daily at locally infected side. Two weeks later, bacterial cultures, radiographic outcomes, histopathology were analyzed. Atomic absorption spectrometry was utilized to measure silver contents in some vital organs of the rabbits to detect the distribution and accumulation of silver particles.

RESULTS

Staphylococcus aureus (100 CFU/mL), induced 100% pyogenic spondylitis. 1 mg/kg dose of silver nanoparticles solution could effectively inhibit the occurrence of spinal pyogenic infection with the effective rate of 75%. While the effect of 0.1 mg/kg dose of silver nanoparticles solution was less obvious, the efficiency was only 25%. Significant numbers of silver nanoparticles were observed to accumulate in the animal. In the 1 mg/kg group silver was deposited mainly in the spinal cord, liver, kidneys, spleen, and testicles, while in the 0.1 mg/kg group it accumulated only in the spinal cord.

CONCLUSION

Local administration of silver nanoparticles can effectively prevent and treat pyogenic spondylitis; the particles accumulate in the body commensurate with the administered drug concentration.

[Surgical management of vertebral sarcoidosis]

OBJECTIVE

To investigate the clinical characteristics, diagnostic foundation and treatment of vertebral sarcoidosis.

METHODS

The clinical data of 13 patients with vertebral sarcoidosis who received anterior debridement and instrumentation were retrospectively analyzed.

RESULTS

The onset of progressive pain in the pathological region was common in the 13 patients. Neurologic deficit existed in 4 cases. Radiographic study showed multiple vertebral bone destructions, and no other systemic lesions were found. Surgical indications were progressive vertebral destruction, spinal instability or neurological deficit. Anterior vertebra resection, and autologous bone grafts fusion with internal fixation were done. No operative mortality and major complications occurred. Diagnosis was confirmed in all patients by pathological exam. After the surgery, metacortandracin treatment was given routinely for 1 year. Patients were followed up for 12-52 (median 26) months, and pain and neurological symptoms were alleviated. Visual analog scale (VAS) score was 7-10 (median 8) points preoperatively, which dropped to 0-4 (median 2) points postoperatively. All patients showed successful bone fusion with no recurrence.

CONCLUSION

For vertebral sarcoidosis associated with progressive instability and/or neurological symptoms, surgical intervention combined with steroid therapy is safe and effective.

[Identification of major gene and polygene mixed inheritance model and estimation of genetic parameters of a quantitative trait from F2 progeny]

It has been proved by many field experiments and QTL mapping results that among genes affecting some quantitative traits there are some major genes with larger genetic effect and some polygenes with smaller genetic effect. For such traits, the distribution of segregating population demonstrates multimodality, and this is the characteristic of the mixture of more than one distributions. Mixture distribution models have been used extensively as models in a wide variety of practical situations where data can be viewed as arising from two or more populations mixed in certain proportions. Akaike's Information Criterion(AIC) has been used to identify the existence of major genes affecting quantitative traits. Under the existence of major genes, the genetic effects of these genes and their genetic variance were estimated through segregation analysis. The genotype of major gene of F2 individuals of were determined by clustering using Bayesian criterion. With P1, P2, F1 and F2 populations, the likelihood ratio test was used to test the existence of polygenes. In the end, the inheritance of soybean flowering date is analyzed. One major gene was found in F2 population derived from Guludou x Shanghaihongmangzao.

Soybean Disease Loss Estimates for the Top 10 Soybean Producing Countries in 1994

Soybean disease loss estimates were compiled for the 1994 harvested crop from the 10 countries with the greatest soybean production. The objective was to document the major soybean disease problems in these countries and any recent changes in the severity of individual soybean diseases. Total yield losses caused by Heterodera glycines in these 10 countries were greater than those caused by any other disease. Next in order of importance were stem canker, brown spot, and charcoal rot. The total yield loss due to disease during 1994 in these countries was 14.99 million metric tons, valued at $3.31 billion. Methods used to estimate soybean disease losses were field surveys, plant disease diagnostic clinic samples, variety trial data, information from field workers and university extension staff, research plots, grower demonstrations, and private crop consultant reports. Yield loss estimates due to a particular disease varied by country. For example, yield losses due to rust were reported from China and Indonesia, but no losses due to this disease were reported from any of the remaining eight countries. Soybean disease control research and extension efforts are needed to provide more effective preventive and therapeutic disease management strategies and systems to producers.

Effect of SR 59026A, a new 5-HT(1A) receptor agonist, on sexual activity in male rats

The effect of SR 59026A, a new selective 5-HT(1A) receptor agonist, was evaluated on sexual behaviour of male rats in different experimental conditions. SR 59026A (1-10mg/kg p.o.) stimulated the copulatory behaviour of sexually experienced rats, as evidenced by a decrease in the number of pre-ejaculatory mounts and intromissions and a shortening of the ejaculation latency. SR 59026A also facilitated the sexual behaviour of naive male rats characterized by a low level of sexual performance: over the same dose range, the percentage of naive males that copulated was significantly increased and the ejaculation latency reduced. In experiments designed to evaluate the onset of sexual satiation, SR 59026A (1 and 3mg/kg) increased significantly the number of ejaculations and delayed the time of sexual satiation. Finally, in agreement with studies on other 5-HT(1A) receptor agonists, SR 59026A did not modify the occurrence of spontaneous erections in isolated male rats. Therefore, the present study shows that SR 59026A improves the sexual performance of male rats in a number of different experimental models, and the compound may prove to be of interest for the treatment of certain states of human male sexual dysfunction.