Antinociceptive and neuroprotective effect of echinacoside on peripheral neuropathic pain in mice through inhibiting P2X7R/FKN/CX3CR1 pathway

Clinically, neuropathic pain treatment remains a challenging issue because the major therapy, centred around pharmacological intervention, is not satisfactory enough to patient by reason of low effectiveness and more adverse reaction. Therefore, it is still necessary to find more effective and safe therapy to ameliorate neuropathic pain. The purpose of this study was to explore the antinociceptive effect of Echinacoside (ECH), an active compound of Cistanche deserticola Ma, on peripheral neuropathic pain induced by chronic constriction injury (CCI) in mice, and to demonstrate its potential mechanism in vivo and vitro. In the present study, results showed that intraperitoneal administration of ECH (50, 100, and 200 mg/kg) could alleviate mechanical allodynia, cold allodynia and thermal hyperalgesia via behavioural test. Moreover, the structure and function of injured sciatic nerve by CCI were taken a turn for the better to a certain extent after ECH treatment using histopathological and electrophysiological test. Furthermore, ECH repressed the expression of the P2X7R and FKN and reduced the expression and release of the IL-1β, IL-6 and TNF-α. Besides, ECH could decrease Ca2+ influx and Cats efflux and inhibit phosphorylation of p38MAPK. To sum up, the present study illustrated that ECH could alleviate peripheral neuropathic pain by inhibiting microglia overactivation and inflammation through P2X7R/FKN/CX3CR1 signalling pathway in spinal cord. This study would provide a new perspective and strategy for the pharmacological treatment on neuropathic pain.

Targeting the chemokine ligand 2-chemokine receptor 2 axis provides the possibility of immunotherapy in chronic pain

Chronic pain affects patients' physical and psychological health and quality of life, entailing a tremendous public health challenge. Currently, drugs for chronic pain are usually associated with a large number of side effects and poor efficacy. Chemokines in the neuroimmune interface combine with their receptors to regulate inflammation or mediate neuroinflammation in the peripheral and central nervous system. Targeting chemokines and their receptor-mediated neuroinflammation is an effective means to treat chronic pain. In recent years, growing evidence has shown that the expression of chemokine ligand 2 (CCL2) and its main chemokine receptor 2 (CCR2) is involved in its occurrence, development and maintenance of chronic pain. This paper summarises the relationship between the chemokine system, CCL2/CCR2 axis, and chronic pain, and the CCL2/CCR2 axis changes under different chronic pain conditions. Targeting chemokine CCL2 and its chemokine receptor CCR2 through siRNA, blocking antibodies, or small molecule antagonists may provide new therapeutic possibilities for managing chronic pain.

[A multicenter epidemiological study of acute bacterial meningitis in children]

Objective: To analyze the clinical epidemiological characteristics including composition of pathogens , clinical characteristics, and disease prognosis acute bacterial meningitis (ABM) in Chinese children. Methods: A retrospective analysis was performed on the clinical and laboratory data of 1 610 children <15 years of age with ABM in 33 tertiary hospitals in China from January 2019 to December 2020. Patients were divided into different groups according to age,<28 days group, 28 days to <3 months group, 3 months to <1 year group, 1-<5 years of age group, 5-<15 years of age group; etiology confirmed group and clinically diagnosed group according to etiology diagnosis. Non-numeric variables were analyzed with the Chi-square test or Fisher's exact test, while non-normal distrituction numeric variables were compared with nonparametric test. Results: Among 1 610 children with ABM, 955 were male and 650 were female (5 cases were not provided with gender information), and the age of onset was 1.5 (0.5, 5.5) months. There were 588 cases age from <28 days, 462 cases age from 28 days to <3 months, 302 cases age from 3 months to <1 year of age group, 156 cases in the 1-<5 years of age and 101 cases in the 5-<15 years of age. The detection rates were 38.8% (95/245) and 31.5% (70/222) of Escherichia coli and 27.8% (68/245) and 35.1% (78/222) of Streptococcus agalactiae in infants younger than 28 days of age and 28 days to 3 months of age; the detection rates of Streptococcus pneumonia, Escherichia coli, and Streptococcus agalactiae were 34.3% (61/178), 14.0% (25/178) and 13.5% (24/178) in the 3 months of age to <1 year of age group; the dominant pathogens were Streptococcus pneumoniae and the detection rate were 67.9% (74/109) and 44.4% (16/36) in the 1-<5 years of age and 5-<15 years of age . There were 9.7% (19/195) strains of Escherichia coli producing ultra-broad-spectrum β-lactamases. The positive rates of cerebrospinal fluid (CSF) culture and blood culture were 32.2% (515/1 598) and 25.0% (400/1 598), while 38.2% (126/330)and 25.3% (21/83) in CSF metagenomics next generation sequencing and Streptococcus pneumoniae antigen detection. There were 4.3% (32/790) cases of which CSF white blood cell counts were normal in etiology confirmed group. Among 1 610 children with ABM, main intracranial imaging complications were subdural effusion and (or) empyema in 349 cases (21.7%), hydrocephalus in 233 cases (14.5%), brain abscess in 178 cases (11.1%), and other cerebrovascular diseases, including encephalomalacia, cerebral infarction, and encephalatrophy, in 174 cases (10.8%). Among the 166 cases (10.3%) with unfavorable outcome, 32 cases (2.0%) died among whom 24 cases died before 1 year of age, and 37 cases (2.3%) had recurrence among whom 25 cases had recurrence within 3 weeks. The incidences of subdural effusion and (or) empyema, brain abscess and ependymitis in the etiology confirmed group were significantly higher than those in the clinically diagnosed group (26.2% (207/790) vs. 17.3% (142/820), 13.0% (103/790) vs. 9.1% (75/820), 4.6% (36/790) vs. 2.7% (22/820), χ²=18.71, 6.20, 4.07, all P<0.05), but there was no significant difference in the unfavorable outcomes, mortility, and recurrence between these 2 groups (all P>0.05). Conclusions: The onset age of ABM in children is usually within 1 year of age, especially <3 months. The common pathogens in infants <3 months of age are Escherichia coli and Streptococcus agalactiae, and the dominant pathogen in infant ≥3 months is Streptococcus pneumoniae. Subdural effusion and (or) empyema and hydrocephalus are common complications. ABM should not be excluded even if CSF white blood cell counts is within normal range. Standardized bacteriological examination should be paid more attention to increase the pathogenic detection rate. Non-culture CSF detection methods may facilitate the pathogenic diagnosis.

[Risk factors and resistance patterns of invasive Acinetobacter Baumannii infection in Children]

Objective: To understand the risk factors and antibiotics-resistant patterns of invasive Acinetobacter baumannii infection in Children. Methods: This retrospective study was conducted in 6 tertiary hospitals from January 2016 to December 2018. The basic information, clinical data and the results of antimicrobial susceptibility testing were collected from the 98 pediatric inpatients with Acinetobacter baumannii isolated from blood or cerebrospinal fluid and analyzed. According to the susceptibility of the infected strains to carbapenems, they were divided into carbapenem-sensitive Acinetobacter baumannii (CSAB) group and carbapenem-resistant Acinetobacter baumannii (CRAB) group. According to the possible sources of infection, they were divided into nosocomial infection group and community infection group. Chi-square test or Fisher exact test were used to analyze categorical variables and rank sum test were used to analyze continuous variables. The risk factors of invasive CRAB infection in children were analyzed by Logistic regression. Result: There were 56 males and 42 females in 98 cases. The onset age of patients was 8 (2, 24) months. There were 62 cases (63%) from rural area. A total of 87 cases (89%) were confirmed with bloodstream infection, and 12 cases (12%) confirmed with meningitis (1 case was accompanied with bloodstream infection). In these patients, 66 cases (67%) received invasive medical procedures or surgery, 54 cases (55%) received carbapenems-containing therapy. Twenty-four cases were infected with CRAB, and 74 cases with CSAB. The onset age of cases in CRAB group was lower than that in CSAB group (4 (1, 9) vs. 10 (4, 24) months, Z=-2.16, P=0.031). The proportions of hospitalization in intensive care unit, carbapenem antibiotics using, pneumonia and adverse prognosis in CRAB group were higher than those in CSAB group (6 cases (25%) vs. 4 cases (5%), 18 cases (75%) vs. 36 cases (49%), 17 cases (71%) vs. 17 cases (23%), 6 cases (25%) vs. 4 cases (5%), χ²=5.61, 5.09, 18.32, 5.61, all P<0.05). Seventy-seven cases were nosocomial infection and 21 cases were hospital-acquired infection. The proportion of children hospitalized in high-risk wards for nosocomial infections, length of hospitalization, number of antimicrobial therapy received and duration of antimicrobial therapy were higher in the hospital associated infection group than those in the community acquired infection group (all P<0.05). Logistic regression analysis showed that children from rural area (OR=8.42, 95%CI 1.45-48.88), prior mechanical ventilation (OR=12.62, 95%CI 1.31-121.76), and prior antibiotic therapy (OR=4.90, 95%CI 1.35-17.72) were independent risk factors for CRAB infection. The resistance percentage of CSAB isolates to many classes of antibiotics was <6% except to gentamicin, which was as high as 20% (13/65). All CRAB isolates of resistant to ampicillin-sulbactam (20/20), cefepime (23/23), piperacillin (17/17), meropenem (23/23) and imipenem (24/24) were 100%. The resistance percentage to other antibiotics were up to 42%-96%. Conclusions: Most of invasive Acinetobacter baumannii infection in children in China are hospital-acquired. The outcome of invasive CRAB infection was poorer than that of CSAB infection. The drug resistance rate of CRAB strains isolated is high. Living in rural area, prior invasive mechanical ventilation and prior antibiotic therapy were independent risk factors for invasive CRAB infection. The prevention and control of nosocomial infection and appropriate use of antibiotics to reduce Acinetobacter baumannii infection.

Glycosides for Peripheral Neuropathic Pain: A Potential Medicinal Components

Neuropathic pain is a refractory disease that occurs across the world and pharmacotherapy has limited efficacy and/or safety. This disease imposes a significant burden on both the somatic and mental health of patients; indeed, some patients have referred to neuropathic pain as being ‘worse than death’. The pharmacological agents that are used to treat neuropathic pain at present can produce mild effects in certain patients, and induce many adverse reactions, such as sedation, dizziness, vomiting, and peripheral oedema. Therefore, there is an urgent need to discover novel drugs that are safer and more effective. Natural compounds from medical plants have become potential sources of analgesics, and evidence has shown that glycosides alleviated neuropathic pain via regulating oxidative stress, transcriptional regulation, ion channels, membrane receptors and so on. In this review, we summarize the epidemiology of neuropathic pain and the existing therapeutic drugs used for disease prevention and treatment. We also demonstrate how glycosides exhibit an antinociceptive effect on neuropathic pain in laboratory research and describe the antinociceptive mechanisms involved to facilitate the discovery of new drugs to improve the quality of life of patients experiencing neuropathic pain.

[Effects of Astragaloside Ⅳ on exosome secretion and its microRNA-126 expression in human endothelial progenitor cells]

Objective: To investigate the effects of Astragaloside Ⅳ on the secretion of exosomes in human endothelial progenitor cells (EPCs) and the expression of microRNA (miRNA)-126 in exosomes. Methods: The umbilical cord blood from one healthy full-term newborn from the Department of Obstetrics and Gynecology of the First Affiliated Hospital of Hunan University of Traditional Chinese Medicine in 2019 was harvested for isolating mononuclear cells by density gradient centrifugation and cultured for 7 days. Morphological observation was performed during this period. Cells of the third passage were collected for identification by CD31 immunomagnetic bead sorting and double fluorescence staining. According to the random number table, the identified EPCs were divided into Astragaloside Ⅳ group and phosphate buffer solution (PBS) group. The cells in Astragaloside Ⅳ group were cultured with Astragaloside Ⅳ in final mass concentration of 100 mg/L for 24 hours, and the cells in PBS group were cultured with the same volume of PBS for 24 hours. After culture, the exosomes from the cell culture supernatant of the two groups were collected, and the expressions of characteristic markers of exosomes CD9, CD63, and CD81 were detected by Western blotting, the morphology of EPC exosomes (EPC-Exos) was observed under transmission electron microscope, and the particle size of EPC-Exos was detected by nanoparticle tracking analysis technique. The concentration of EPC-Exos was determined by dioctyl butyric acid method (the sample number was 3), and the expressions of miRNA-126-3p and miRNA-126-5p related to angiogenesis in EPC-Exos were determined by reverse transcription polymerase chain reaction (the sample number was 3). Data were statistically analyzed with independent sample t test. Results: (1) On the 4th day of culture, the cells began to adhere to the wall, and the multi-forms such as circle, fusiform, and strip appeared at the same time. On the 7th day of culture, the edge of the cells was clear and arranged like a paving stone, the central cells were round, and the surrounding cells were fusiform. (2) CD31 immunomagnetic beads sorting method identification showed that the membrane was stained with green fluorescence and the nucleus was stained with blue fluorescence. Double fluorescence staining method showed that the cells were orange-yellow. The cells were identified as EPCs. (3) After 24 hours of culture, the expressions of CD9, CD63, and CD81 in EPC-Exos were all positive, confirming that EPC-Exos were extracted successfully in this experiment. (4) After 24 hours of culture, the EPC-Exos of the two groups showed round membrane vesicles, and there was no significant difference in morphology. (5) After 24 hours of culture, the particle size of 98.7% EPC-Exos in Astragaloside Ⅳ group was 84.7 to 143.1 nm, and that of 98.0% EPC-Exos in PBS group was 88.7 to 123.5 nm. (6) After 24 hours of culture, the mass concentration of EPC-Exos in Astragaloside Ⅳ group was (310±5) μg/mL, which was significantly higher than (257±5) μg/mL in PBS group, t=13.369, P<0.01. (7) After 24 hours of culture, there were more miRNA-126-3p (t=16.062, P<0.01) and miRNA-126-5p (t=3.252, P<0.05) in EPC-Exos of Astragaloside Ⅳ group than in PBS group. Conclusions: Astragaloside Ⅳ can improve the function of human EPC secretory exosomes, and the secreted exosomes are loaded with miRNA-126.

[Clinical observation of different reperfusion methods in patients with acute ischemic stroke with atrial fibrillation within 4.5 hours from onset]

Objective: To detect the ideal treatment for acute ischemic stroke (AIS) patients with atrial fibrillation (AF) within 4.5 hours from onset. Methods: A total of 95 AIS patients with AF was retrospectively analyzed from April 2014 to January 2019. Thirty patients (group A) were treated with endovascular treatment directly, 35 (group B) patients were treated with intravenous recombinant tissue plasminogen activator (rtPA) followed by endovascular treatment, and 30 (group C) patients were treated with intravenous rtPA only. There were no significant differences among the groups in baseline data as age, gender, underlying diseases, medication, National Institutes of Health Stroke Scale (NIHSS) score, time from onset to treatment. Modified thrombolysis in cerebral infarction (mTICI), Symptomatic hemorrhagic transformation (SICH), 90 d prognosis of modified Rankin Scale (mRS) and death were compared. Results: Recanalization (mTICI≥2b) was similar in group A and B (70.0% vs. 68.6%, P>0.05). SICH of group A (6.7%) was significantly lower than that of group B (31.4%, P<0.05), but similar with that of group C (13.7%, P>0.05). Prognosis (mRS≤2) was significantly better in group A (70.0%) than that in group B (37.1%) and group C (30.0%), both P<0.01. The mortality rate in group A (6.7%) was lower than that in group B (14.3%) and group C (20.0%) without statistically significant, both P>0.05. Conclusion: AIS patients with AF within 4.5 hours from onset should receive endovascular treatment directly.

[Prevalence and risk factors of diabetic peripheral neuropathy in Chinese communities]

Objective: To investigate the prevalence and risk factors of diabetic peripheral neuropathy in type 2 diabetic patients under community management programs. Methods: A cross-sectional study was conducted on T2DM patients in eight communities in Wuhan and Changshu cities. Data would included questionnaire, body measurement, blood testing and clinical examination. The criterion of diabetic peripheral neuropathy was under the combination of symptoms with five physical examinations. Binary logistic regression model was used to analyze the influential factors. Results: The overall prevalence of peripheral neuropathy was 71.2% among the diabetic patients who were managed in primary care health services in the two cities. The binary logistic regression method identified older age (≥60 years, OR=2.39, 95%CI:1.95-2.94), longer diabetic duration (≥10 years, OR=1.25, 95%CI: 1.02-1.54), and worse postprandial glucose control (2 h postprandial plasma glucose >10.0 mmol/L: OR=1.65, 95%CI:1.33-2.04) (all P<0.05) as risk factors for the presence of diabetic peripheral neuropathy, while higher education level was protective factor (compared to patients with education levels of primary school or below, OR=0.52, 95%CI: 0.41-0.66; OR=0.59, 95%CI: 0.44-0.79; OR=0.64, 95%CI: 0.44-0.94 for those with education levels of junior high school, senior high school, and college, respectively). Conclusions: High rates of diabetic peripheral neuropathy among T2DM patients suggested the urgent need for early screening and standardized management at the community levels. It is necessary to promote appropriate screening techniques and methods to identify the peripheral neuropathy, in the primary health service institutions.

[The health status of radiation workers and the analysis of crystalline lens results]

Objective: To understand the healthy status of radiation workers on the staff in Nanjing, and to analysis the relationship between abnormal crystalline lens and its influencing factors. Methods: We described physical indicators including blood pressure (BP) 、blood sugar (BG) 、thyroid B ultrasound、crystalline lens、chromosome and so on among 3 349 radiation workers on the staff in the year 2016 from Jan 1 to Dec 31, and the abnormal results of crystalline lens were analyzed statistically. Results: The rate of abnormal BP、BG、WBC、Thyroid B ultrasound、crystalline lens was 19.0%、2.2%、5.8%、30.0%、3.6% respectively; The rate of chromosome aberration was 0.1%, and the chromosomal micronuclei are all within normal range. With the rate of abnormal crystalline lens increasing in age and working years, statistical significance both existed in the trend; Compared to the lowest group, the risk of abnormal crystalline lens increased 3.86 times in ≥60 year old group and 3.16 times in ≥30 years working group; The risk of abnormal crystalline lens in nosocomial radation group was higher than non-medical group; There's no found in smoking and drinking alcohol increasing the risk. Morphologically, dot abnormal focused on 30~39 years old and 0~9 working years group, while lamellar abnormal concentrated upon ≥60 year old、≥30 working years group; Age and working-year were both the risk factors of lamellar abnormal; The risk of lamellar abnormal in nosocomial radiation group was significantly higher than non-medical group. Conclusion: Existing nisk foctions in the radiation work has a serious impact on several healthy physiology indicators, the more prominent was crystalline lens. Attention should be paid to eye protection and comprehensive health management.

[Effects of nasogastric and percutaneous endoscopic gastrostomy tube feeding on the susceptibility of pulmonary infection in long-term coma patients with stroke or traumatic brain injury]

Objective: To investigate the effects of nasogastric tube (NGT) and percutaneous endoscopic gastrostomy (PEG) tube feeding on the susceptibility of pulmonary infection in long-term coma patients with stroke or traumatic brain injury. Methods: A total of 295 candidates who were in long-term coma after stroke or traumatic brain injury but without pulmonary infection and eligible for PEG catheterization were screened prospectively between January 2014 and February 2018. The patients were divided into PEG group (86 patients) and NGT group (209 patients) according to the choice of next-of-kin. Data related to the susceptibility of pulmonary infection were collected and analyzed in the two groups one month after the catheterization. Results: After follow-up for one month, compared with NGT group, patients in PEG group had a lower incidence of pulmonary infection (23.3% vs 37.8%, P=0.023), a later occurrence of pulmonary infection (average time: 21 days vs 13 days, P=0.034), and a less severe pulmonary infection (7.0% vs 12.9%, P=0.029). The following characteristics made patients more susceptible to pulmonary infection: age ≥ 70 years (HR=1.619, 95% CI 1.054-2.172), Charlson comorbidity index ≥ 2 points (HR=1.647, 95% CI 1.043-2.485), using of proton pump inhibitor ≥ 7 days (HR=1.725, 95% CI 1.214-2.738), and number of pressure ulcers ≥ 3 (HR=2.109, 95% CI 1.128-3.844). However, serum albumin concentration ≥35 g/L (HR=0.670, 95% CI 0.375-0.963) was a protective factor for pulmonary infections. The number of consistent pathogens cultivated from saliva, gastric juice and sputum simultaneously in NGT and PEG group was 35 strains (27.8%) and 8 strains (13.3%), respectively (P=0.029). The mortality of pulmonary infection was similar in the two groups (3.5% vs 4.3%, P=1.000), but the death due to pulmonary infection in the PEG group occur later (median time: 20 days vs 11 days, P=0.012). Conclusions: PEG feeding was a preferred nutrition way which could reduce the risk of pulmonary infection more effectively than NGT feeding which might favored a retrograde gastro-pulmonary route by which pathogens colonized in stomach migrated to respiratory tract. Patients with characteristics mentioned above had the susceptibility of pulmonary infection, thus risk assessment of pulmonary infection should be conducted before selecting the catheterization method.

[Effect of Dishevelled 2 on apoptosis in rheumatoid arthritis fibroblast-like synoviocytes through inhibiting JAK-STAT pathway]

Objective: To investigate if Dishevelled 2 (DVL2) regulates the apoptosis of rheumatoid arthritis fibroblast-like synoviocytes (RA-FLS) via the JAK-STAT pathway. Methods: DVL2 overexpressed lentivirus was transfected into RA-FLS and the apoptosis rate was detected by flow cytometry. The effect of DVL2 on RA-FLS signaling pathway was detected by RNA-seq, and then the key genes were verified by RT-PCR. Results: Compared with the control group, DVL2 significantly increased the apoptosis rate of MH7A (3.2%±2.2% vs 25.7%±4.5%). RNA-seq results showed that DVL2 down-regulated the JAK-STAT pathway.The results of RT-PCR showed that DVL2 inhibited the gene expression of JAK2, Stat1, and Stat2; DVL2 still inhibited the gene expression of JAK2 and Stat2 but not Stat1 after TNF-α stimulation.DVL2 inhibited the gene expression of Bcl-xL, and the gene expression of Bcl-2 and Bcl-xL after TNF-α stimulation. Conclusion: DVL2 can increase the apoptosis rate of RA-FLS through inhibiting the JAK-STAT pathway and its downstream anti-apoptotic gene.

[Significance of monitoring the gradients between transcutaneous PCO(2) and end-tidal PCO(2) in patients with septic shock]

Objective: To investigate the significance of monitoring the gradients between transcutaneous PCO(2) and end-tidal PCO(2) [P(c-et)CO(2)] in patients with septic shock. Method: Thirty-five mechanically ventilated patients with early septic shock were enrolled as the study group and 18 non-septic shock patients with stable hemodynamics as the control group between May 2014 and October 2016. The patients with septic shock were treated by early goal-directed therapy (EGDT) within 6 hours since hospitalization. The differences of baseline level of P(c-et)CO(2) and arterial lactate concentration (LAC) between the two groups and the variations of these indexes after EGDT in the study group were compared respectively. Results: The baseline levels of P(c-et)CO(2) and LAC in patients with septic shock were significantly higher than those of the control group [(26.0±16.2) mmHg vs (11.0±5.6) mmHg (1 mmHg=0.133 kPa) and (4.0±1.7) mmol/L vs (1.6±0.6)mmol/L, all P=0.000]. The area under receiver operator characteristic (ROC) curve (AUC) for baseline P(c-et)CO(2) and LAC was 0.924 (95%CI: 0.851-0.996) and 0.931 (95%CI: 0.872-1.000), respectively. P(c-et)CO(2) >12.6 mmHg and LAC >2.5 mmol/L could discriminate septic shock patients from those without shock with the same sensibility of 97% and the specificity of 83% and 78% respectively. With regard to the prognosis (Day 28) of the patients with septic shock, AUC for baseline P(c-et)CO(2) and LAC was 0.709 (95%CI: 0.533-0.886) and 0.714 (95%CI: 0.545-0.883), respectively. P(c-et)CO(2) >20.0 mmHg and LAC>3.6 mmol/L could discriminate survivors from non-survivors with the same sensibility of 92% and the same specificity of 76%. All the patients in the study group completed EGDT within 6 hours after admission, 20 (57.1%) passed EGDT and 17 (85.0%) survived, 15 (42.9%) failed EGDT and 4 (26.7%) survived, and the survival rates were significantly different (F=9.844, P=0.001). After EGDT, P(c-et)CO(2) (21.0±9.5 mmHg) and LAC(3.3±2.5 mmol/L)reduced significantly compared with the baselines (P=0.008 and P=0.046), and the associated AUC was 0.905(95%CI: 0.792-1.000) and 0.747 (95%CI: 0.576-0.917)respectively. P(c-et)CO(2) > 16.5 mmHg and LAC > 3.1 mmol/L could discriminate survivors from non-survivors with the sensibility of 97% and 91%, and the specificity of 78% and 69%, respectively. Conclusions: P(c-et)CO(2) >12.6 mmHg could play the same role as LAC in recognizing early septic shock. EGDT was an effective therapy for the septic shock and P(c-et)CO(2) reflected efficacy. P(c-et)CO(2)>20 mmHg before EGDT and >16.5 mmHg after EGDT both could predict the 28 d prognosis of patients with septic shock, and the effect of the former was equal to that of LAC, but the latter was better than LAC.

Multiple variants in 5q31.1 are associated with systemic lupus erythematosus susceptibility and subphenotypes in the Han Chinese population

BACKGROUND

A previous study provided evidence for a genetic association between PPP2CA on 5q31.1 and systemic lupus erythematosus (SLE) across multi-ancestral cohorts, but failed to find significant evidence for an association in the Han Chinese population.

OBJECTIVES

To explore the association between this locus and SLE using data from our previously published genome-wide association study (GWAS).

METHODS

Single-nucleotide polymorphisms (SNPs) rs7726414 and rs244689 (near TCF7 and PPP2CA in 5q31.1) were selected as candidate independent associations from a large-scale study in a Han Chinese population consisting of 1047 cases and 1205 controls. Subsequently, 3509 cases and 8246 controls were genotyped in two further replication studies. We then investigated the SNPs' associations with SLE subphenotypes and gene expression in peripheral blood mononuclear cells.

RESULTS

Highly significant associations with SLE in the Han Chinese population were detected for SNPs rs7726414 and rs244689 by combining the genotype data from our previous GWAS and two independent replication cohorts. Further conditional analyses indicated that these two SNPs contribute to disease susceptibility independently. A significant association with SLE, age at diagnosis < 20 years, was found for rs7726414 (P = 0·001). The expression levels of TCF7 and PPP2CA messenger RNA in patients with SLE were significantly decreased compared with those in healthy controls.

CONCLUSIONS

This study found evidence for multiple associations with SLE in 5q31.1 at genome-wide levels of significance for the first time in a Han Chinese population, in a combined genotype dataset. These findings suggest that variants in the 5q31.1 locus not only provide novel insights into the genetic architecture of SLE, but also contribute to the complex subphenotypes of SLE.

Genetic differences in ChTLR15 gene polymorphism and expression involved in Salmonella enterica natural and artificial infection respectively, of Chinese native chicken breeds, with a focus on sexual dimorphism

Chicken Toll-like receptor 15 (ChTLR15) has been shown to participate in immune activation in response to various pathogens and in the innate defence against infection. Two genetically distinct Chinese breeds of chicken (Qinyuan Partridge and Baier breeds) were used to study the correlation between ChTLR15 single nucleotide polymorphisms and the natural infection status of salmonella in hens, and also to examine genetic and sex-specific effects on ChTLR15 mRNA expression in heterophils and spleen during acute infection with Salmonella enterica serovar Enteritidis (SE) from 1 to 10 days after experimental infection. Three single-nucleotide polymorphisms (G168A, C726T and A1166G) in a single exon of ChTLR15 were identified in the two breeds, but only C726T showed a significant association with salmonella infection. Compared with layer-type Baier chicks, meat-type Qingyuan chicks showed a higher tolerance for capture stress and (SE) infection, as measured, respectively, by the modified body weight of chicks in the control group and in the infection group. Meanwhile, ChTLR15 down-regulation in heterophils and up-regulation in spleen were involved in the response to pathogenic SE colonization during the acute infection period. These significant genetic effects in females led to greater differences in both innate and adaptive immune responses than those exhibited in males. These results suggest that genetics, time and gender play important roles in the modulation of ChTLR15 mRNA level elicited by the SE-mediated immune response differentially in the two genetically distinct breeds, with a focus on sexual dimorphism.

[Acute impact of cold spells on mortality during 2001-2011 in Jiang'an district of Wuhan, China]

OBJECTIVE

To evaluate the association between cold spells and nonaccidental mortality from 2001 to 2011 in the Jiang'an District of Wuhan, China.

METHODS

We collected mortality data for December 2001 to 2010 and January to March 2002 to 2011 in the study area. According to the International Classification of Diseases, we stratified the mortality data into three cause-specific categories: nonaccidental mortality, cardiovascular mortality, and respiratory mortality. We also obtained meteorological data (from the China Meteorological Administration) and ambient pollution data (from the Wuhan Environmental Monitoring Center) during the same periods. In the present study, a cold spell was defined as 5 or more consecutive days with daily average temperatures below the 5th percentile of daily mean temperatures (2.58 ℃) from January to December in 2001-2011. A distributed lag nonlinear model (DLNM) was applied to assess the acute effect of cold spells on daily nonaccidental mortality.

RESULTS

During the study period, the total number of nonaccidental deaths was 17 119, including 9 403 (75.5%) among individuals aged over 65 years; 7 968 (46.5%) people died of cardiovascular disease. According to this definition, there were a total of 13 cold spell events and 111 days of duration in Wuhan during the study period. Study days were divided into three periods: non-cold spell days, 2008 cold spell days, and cold spell days in other years. Average daily mean temperatures of the above three periods were (8.2±4.5), (-0.7±1.4), and (0.8±1.2) ℃, respectively, corresponding to average daily deaths of 14.0±4.2, 18.2±4.5, and 14.9±4.9 for nonaccidental mortality. After adjusting for long-term trends, seasonal trends, weekdays, holidays, and relative humidity, analysis by the DLNM revealed that cold spells were associated with increased mortality risk, with a cumulative relative risk (RR) of 1.56 (95% CI: 1.36-1.79) at lag 0-27 days in 2008, higher than that in other years with 1.23 (95%CI: 1.08-1.41). Cold spells were not significantly associated with respiratory mortality and people under 65 years of age; however, during the 2008 cold spell RR increased to 1.96 (95% CI: 1.62-2.37) and 1.67 (95% CI: 1.43-1.95) for cardiovascular mortality and older adults (≥65 years old), respectively; both males and females had high mortality risk, with RRs of 1.60 (95%CI:1.33-1.92) and 1.50 (95% CI: 1.23-1.84), respectively. The association between cold spells and mortality remained nearly unchanged with and without adjustment for ambient pollutants (PM10, SO2, and NO2) in the DLNMs.

CONCLUSION

In Wuhan, both the 2008 cold spell and cold spells in other years were significantly associated with increased nonaccidental mortality. People with cardiovascular disease and elderly adults may be more susceptible to the impact of cold spells on mortality.

[Temperature modifies the acute effect of particulate air pollution on mortality in Jiang'an district of Wuhan]

OBJECTIVE

To analyze the temperature modification effect on acute mortality due to particulate air pollution.

METHODS

Daily non-accidental mortality, cardiovascular mortality, and respiratory mortality data were obtained from Jiang'an District Center for Disease Control and Prevention. Daily meteorological data on mean temperature and relative humidity were collected from China Meteorological Data Sharing Service System. The daily concentration of particulate matter was collected from Wuhan Environmental Monitoring center. By using the stratified time-series models, we analyzed effects of particulate air pollution on mortality under different temperature zone from 2002 to 2010, meanwhile comparing the difference of age, gender and educational level, in Wuhan city of China.

RESULTS

High temperature (daily average temperature > 33.4 ℃) obviously enhanced the effect of PM10 on mortality. With 10 μg/m(3) increase in PM10 concentrations, non-accidental, cardiovascular, and respiratory mortality increased 2.95% (95%CI: 1.68%-4.24%), 3.58% (95%CI: 1.72%-5.49%), and 5.07% (95%CI: 2.03%-9.51%) respectively. However, low temperature (daily average temperature <-0.21 ℃) enhanced PM10 effect on respiratory mortality with 3.31% (95% CI: 0.07%-6.64%) increase. At high temperature, PM10 had significantly stronger effect on non-accidental mortality of female aged over 65 and people with high educational level groups. With an increase of 10 μg/m(3), daily non-accidental mortality increased 4.27% (95% CI:2.45%-6.12%), 3.38% (95% CI:1.93%-4.86%) and 3.47% (95% CI:1.79%-5.18%), respectively. Whereas people with low educational level were more susceptible to low temperature. A 10 μg/m(3) increase in PM10 was associated with 2.11% (95% CI: 0.20%-4.04%) for non-accidental mortality.

CONCLUSIONS

Temperature factor can modify the association between the PM10 level and cause-specific mortality. Moreover, the differences were apparent after considering the age, gender and education groups.

Upregulation of NRAMP1 mRNA confirms its role in enhanced host immunity in post-artificial infections of Salmonella enteritidis in chicks

1. Salmonella enteritidis (SE) is reported as the most common food-borne pathogen transmitted through poultry products. The natural resistance-associated macrophage protein 1 (NRAMP1) is a candidate gene associated with SE-mediated immune response and is related to the phagocytosis of SE. In this study, the classical single-nucleotide polymorphism (SNP) G2357A in exon 8 of the NRAMP1 gene was detected. The expression of NRAMP1 mRNA was first investigated in heterophil granulocytes and spleen in chicks from two different Chinese native breeds at 1, 3 and 10 d post-infection. In addition, the association with the effect of SE challenge was identified. 2. The G2357A SNP showed no significant association with Salmonella natural infection in birds from two different Chinese native breeds. 3. The upregulation of NRAMP1 mRNA in heterophils and spleen was involved in the response to pathogenic SE colonisation during the acute infection period in chicks. The results suggest that genetics, age, gender and interactions among these factors play important roles in the modulation of NRAMP1 mRNA expression and copy number by SE-mediated immune response in different Chinese chickens. 4. In conclusion, the enhancement of host immunity mediated by the upregulation of NRAMP1 mRNA in heterophil granulocytes and spleen might be more obvious and earlier in the chicks resistant to infections with SE than in susceptible chicks.

Expression of APPL1 is correlated with clinicopathologic characteristics and poor prognosis in patients with gastric cancer

BACKGROUND

Although appl1 is overexpressed in many cancers, its status in gastric cancer (gc) is not known. In the present study, we used relevant pathologic and clinical data to investigate appl1 expression in patients with gc.

METHODS

In 47 gc and 27 non-gc surgical specimens, immunohistochemistry was used to detect the expression of appl1, and reverse-transcriptase polymerase chain reaction (rt-pcr) was used to detect messenger rna (mrna). A scatterplot visualized the relationship between survival time and mrna expression in gc patients. The log-rank test and other survival statistics were used to determine the association of appl1 expression with the pathologic features of the cancer and clinical outcomes.

RESULTS

In gc, appl1 was expressed in 28 of 47 specimens (59.6%), and in non-gc, it was expressed in 7 of 23 specimens (30.4%, p < 0.05). The expression of mrna in gc was 0.82 [95% confidence interval (ci): 0.78 to 0.86], and in non-gc, it was 0.73 (95% ci: 0.69 to 0.77; p < 0.05). Immunohistochemistry demonstrated that, in gc, appl1 expression was correlated with depth of infiltration (p = 0.005), lymph node metastasis (p = 0.017), and TNM stage (p = 0.022), but not with pathologic type (p = 0.41). Testing by rt-pcr demonstrated that, in gc, appl1 mrna expression was correlated with depth of infiltration (p = 0.042), lymph node metastasis (p = 0.031), and TNM stage (p = 0.04), but again, not with pathologic type (p = 0.98). The correlation coefficient between survival time and mrna expression was -0.83 (p < 0.01). Overexpression of appl1 protein (hazard ratio: 3.88; 95% ci: 1.07 to 14.09) and mrna (hazard ratio: 4.23; 95% ci: 3.09 to 15.11) was a risk factor for death in patients with gc.

CONCLUSIONS

Expression of appl1 is increased in gc. Overexpression is prognostic for a lethal outcome.

Molecular cloning, characterization, and expression profiles of androgen receptors in spotted scat (Scatophagus argus)

Androgen plays critical roles in vertebrate reproductive systems via androgen receptors (ARs). In the present study, the full-length spotted scat (Scatophagus argus) androgen receptor (sAR) cDNA sequence was cloned from testis. The sAR cDNA measured 2448 bp in length with an open-reading frame of 2289 bp, encoding 763 amino acids. Amino acid alignment analyses showed that the sARs exhibited highly evolutionary conserved functional domains. Phylogenetically, the sARs clustered within the ARβ common vertebrate group. Real-time polymerase chain reaction (RT-PCR) revealed that sAR expression varied in level and distribution throughout the tissues of both females and males. sAR expression was detected during testicular development by quantitative RT-PCR. The results showed that the highest transcription of sARs was observed in the mid-testicular stage, and remained at a high expression level until the late-testicular stage. In addition, the effects of 17α-methyltestosterone (MT) and estrogen (E2) on the expression of sARs in ovaries were determined using quantitative RT-PCR. sAR expression increased at 12 and 24 h post-MT treatment and decreased with E2 treatment. The present study provides preliminary evidence indicating gonadal plasticity of spotted scat under exogenous steroidal hormone treatments. It also provides a theoretical basis for sex reversal and production of artificial pseudo-males for female monosex breeding.

In vivo and in vitro inhibitory action of 17β-estradiol and environmental estrogen 4-nonylphenol on gonad-inhibiting hormone (GIH) expression in the eyestalks of Litopenaeus vannamei

The gonad-inhibiting hormone (GIH) belongs to a neuropeptide family synthesized and released in an X-organ sinus gland complex of crustacean eyestalks. GIH inhibits crustacean ovarian maturation by suppressing vitellogenin (Vtg) synthesis, whereas estrogen is responsible for the stimulation of vitellogenesis (not established). In this study, the effects of 17β-estradiol (E2, 10(-6) M), estrogen receptor antagonist tamoxifen (TAM, 10(-6), 10(-7), and 10(-8) M), and the environmental estrogen nonylphenol (NP, 1 μg/L and 100 μg/L) on LvGIH expression in the eyestalks of shrimp were determined by quantitative real-time PCR. Results showed that LvGIH expression decreased significantly during the L. vannamei ovarian maturation cycle. E2 and NP significantly reduced LvGIH transcripts in vivo, but TAM neutralized the inhibitory action of E2 in a dose-dependent manner (P < 0.05). In addition, the LvGIH expression levels decreased significantly in a time-dependent manner (P < 0.05) when ovary fragments were cultured in vitro with E2. The results of this study suggested that estrogen regulates GIH expression in L. vannamei eyestalks. E2 promoted ovarian development not only by directly upregulating vitellogenesis in the hepatopancreas, but it was also capable of downregulating LvGIH expression, which indirectly resulted in the stimulation of L. vannamei vitellogenesis.

Construction of a lentiviral vector encoding heme oxygenase 1 and its introduction into mouse adipose tissue-derived stem cells

Many studies exist concerning the use of stem cells as delivery vehicles in gene therapy, expressing genes such as vascular endothelial growth factor 165 and hepatocyte growth factor. However, few reports regarding adipose tissue-derived stem cells (ADSCs) and the heme oxygenase 1 (HO-1) gene have been published. Therefore, we established a lentiviral vector encoding HO-1 and used this to infect ADSCs with the aim of producing therapeutic seed cells. In this study, ADSCs were isolated from mouse adipose tissue (AT), cultured, and identified according to the expression of antigens on their cell surface and their capacity for multilineage differentiation. A lentiviral vector encoding HO-1 was constructed, ADSCs were infected with this, and HO-1 protein expression was examined by western blotting. Our results show that ADSCs can be isolated from mouse AT, while DNA sequencing demonstrated that HO-1 was successfully transferred to the vector fused with GFP. Following 293T cell transfection, lentivirus titers were approximately 3 x 10(8) TU/mL. Fluorescence microscopy confirmed the expression of the HO-1 construct in lentivirus-infected ADSCs and the overexpression of HO-1 protein in these cells was verified by western blot. The production of ADSCs overexpressing HO-1 described in this study may aid in the development of a novel method for the treatment of asthma.

Co-expression of recombinant human prolyl with human collagen α1 (III) chains in two yeast systems

In this study, we co-expressed the human prolyl 4-hydroxylases (P4H) with human collagen α1 (III) (COL3A1) in an inducible system: Pichia pastoris (pPICZB), and one constitutive system: P. pastoris (pGAPZαB). The P4H catalyses the post-translational hydroxylation of proline residues in collagen strands. Conventional protein expression system such as bacteria and yeasts, which lack endogenous P4H, are not efficient for the production of recombinant collagen. In this study, the P4H gene was constructed in pGAPZαB plasmid and pPICZB plasmid respectively. These two plasmids were transformed in P. pastoris #1 that carrying COL3A1. Colony PCR analysis and sequencing after electroporation P. pastoris GS115 showed that the target gene had inserted successfully. The results of reverse transcript-qPCR, SDS-PAGE, Western blotting and LC-MS/MS analysis of the rhCOL3A1 demonstrated that the P4H was expressed successfully. Besides, it is noted that low copy number, constitutive system was suitable for hydroxylated rhCOL3A1.

SIGNIFICANCE AND IMPACT OF THE STUDY

Successful co-expression of recombinant human collagen α1 (III) (rhCOL3A1) and human prolyl 4-hydroxylases (P4H) in Picha pastoris GS115, simultaneously results in the acquisition of rhCOL3A1 with hydroxylation of proline (Hyp). Further, this experiment also discusses that the high or low copy numbers and different promoters affect the Hyp degree of rhCOL3A1. Selecting more appropriate strains can express high degree Hyp of rhCOL3A1. This work will be helpful to the collagen structure study.

Molecular characterization, expression, and functional analysis of NOD1 in Qingyuan partridge chicken

Nucleotide-binding oligomerization domain-containing protein-1 (NOD1) is a cytoplasmic pattern recognition receptor (PRR) and a key member of the NOD-like receptor (NLR) family. It has been reported that NLRs recognize a variety of microbial infections to induce the host innate immune response via modulation of NF-κB signaling. However, no reports on chicken NOD1 have been reported to date. In the current study, the full-length cDNA sequence of NOD1 was cloned. The complete open reading frame of NOD1 contains 2856 bp and encodes a 951 amino acid protein. Structurally, it is comprised of one caspase recruitment domain at the N-terminus, seven leucine-rich repeat regions at the C-terminus, and one NACHT domain between the N and C-termini. Phylogenetic analyses showed that chicken NOD1 clusters with duck and turkey. Furthermore, tissue-specific expression analyses of chicken NOD1 were performed using quantitative reverse transcription-PCR. NOD1 is widely distributed in various tissues, with the highest expression observed in testes. Finally, induced expression of chNOD1 and its associated adaptor molecule receptor-interacting protein 2, as well as the effector molecule NF-κB, was observed following S. enterica serovar Enteritidis infection. These findings highlight the important role of chicken NOD1 in response to pathogenic invasion. The present study is the first report of the cloning, expression, and functional analysis of chicken NOD1 and provides the foundation for future research on the structure and function of chicken NOD1.

Molecular genetic diversity and maternal origin of Chinese black-bone chicken breeds

Chinese black-bone chickens are valued for the medicinal properties of their meat in traditional Chinese medicine. We investigated the genetic diversity and systematic evolution of Chinese black-bone chicken breeds. We sequenced the DNA of 520 bp of the mitochondrial cyt b gene of nine Chinese black-bone chicken breeds, including Silky chicken, Jinhu black-bone chicken, Jiangshan black-bone chicken, Yugan black-bone chicken, Wumeng black-bone chicken, Muchuan black-bone chicken, Xingwen black-bone chicken, Dehua black-bone chicken, and Yanjin black-bone chicken. We found 13 haplotypes. Haplotype and nucleotide diversity of the nine black-bone chicken breeds ranged from 0 to 0.78571 and 0.00081 to 0.00399, respectively. Genetic diversity was the richest in Jinhu black-bone chickens and the lowest in Yanjin black-bone chickens. Analysis of phylogenetic trees for all birds constructed based on hyplotypes indicated that the maternal origin of black-bone chickens is predominantly from three subspecies of red jungle fowl. These results provide basic data useful for protection of black-bone chickens and help determine the origin of domestic chickens.

Metabolizable energy and fiber digestibility of uncommon feedstuffs for geese

This experiment was conducted to study the digestibility of uncommon feedstuffs for geese. Thirty Taihu ganders were selected and divided into 5 groups (n = 6), and one group was allocated as the control. Taihu ganders in the 4 treated groups were force-fed with a weight of different uncommon feedstuffs after 24 h of fasting, and the control group was kept in fasting with no force feeding. All excretion of each gander was collected on a plate for 24 h after force feeding. There was a 12-d recovery period between treatments. In this study, we measured the ME and analyzed neutral detergent fiber, acid detergent fiber, and hemicellulose of brewers grains, distillers grains, empty-grain rice, ryegrass powder, rice husk, corn stalk, rice straw, wheat straw, wheat husk, mushroom bran, and peanut vine. The TME values were 9.29, 8.67, 8.97, 5.89, 3.85, 3.10, 3.32, 3.02, 5.29, 2.48, and 3.15 MJ/kg, respectively. The digestibility of neutral detergent fiber for the feedstuffs ranged from 6.14 to 45.0%, the digestibility of acid detergent fiber ranged from 4.52 to 32.6%, and the digestibility of hemicellulose ranged from 18.5 to 61.6%. The best TME quadratic prediction equation was TME = 12.2 - 0.232CF, where CF is crude fiber. These results suggest that geese were able to use uncommon feedstuffs with high digestibility, and there was a significant negative correlation between energy digestibility and CF content. The ME values tested in this experiment can provide a foundation for preparation and adjustment of feed formulation for reasonable use of uncommon feedstuffs for geese.

SNX10 is required for osteoclast formation and resorption activity

RANKL-stimulation of osteoclast precursors results in up-regulation of genes involved in the process of differentiation and activation. In this report we describe the expression and functional characterization of Sorting Nexin 10 (snx10). Snx10 belongs to the sorting nexin (SNX) family, a diverse group of proteins with a common feature: the PX domain, which is involved in membrane trafficking and cargo sorting in endosomes. Snx10 is strongly up-regulated during RANKL-induced osteoclast differentiation in vitro and expressed in osteoclasts in vivo. qPCR analysis confirmed a significant increase in the expression of snx10 in in vitro-derived osteoclasts, as well as in femur and calvaria. Immunohistochemical analysis of mouse embryo sections showed expression in long bone, calvariae, and developing teeth. The expression was limited to cells that also expressed TRAP, demonstrating osteoclastic localization. Confocal immunofluorescence and subcellular fractionation analysis revealed Snx10 localization in the nucleus and in the endoplasmic reticulum (ER). To study a possible role for snx10 in osteoclast differentiation and function we silenced snx10 expression and found that snx10 silencing inhibited RANKL-induced osteoclast formation and osteoclast resorption on hydroxyapatite. Silencing also inhibited TRAP secretion. Taken together, these results confirm that snx10 is expressed in osteoclasts and is required for osteoclast differentiation and activity in vitro. Since inhibition of vesicular trafficking is essential for osteoclast formation and activity and SNX10 is involved in intracellular vesicular trafficking, these studies may identify a new candidate gene involved in the development of human bone diseases including osteoporosis.

Comparison of a Commercial ELISA with the Modified Agglutination Test for Detection of Toxoplasma gondii Antibodies in Sera of Naturally Infected Dogs and Cats

BACKGROUND

Toxoplasma gondii can infect all warm-blooded animals. Modified agglutination test (MAT) and ELISA are widely used for the detection of T. gondii antibodies. However, there is little information on their acceptability for detecting antibodies in companion animals.

METHODS

This study compared ELISA and MAT for their ability to detect T. gondii infection in naturally infected dogs and cats. Blood samples were collected from dogs and cats in different areas of Beijing, China and analyzed by ELISA and MAT. The χ(2) test and κ analysis were used to evaluate their efficiency and agreement.

RESULTS

For dogs, the seroprevalence of T. gondii antibodies detected by ELISA was 34.7%, which was significantly higher than that detected by MAT (P<0.05). There was no significant difference between ELISA and MAT for detecting T. gondii antibodies in cats. Good agreements between MAT and ELISA were seen in both dogs and cats; however, inconsistent results were demonstrated by κ analysis and in MAT titer assay.

CONCLUSION

Serum-based ELISA may be more satisfactory for screening test of T. gondii infection in dogs, whereas both methods could be acceptable in cats.

Difference and variation of the sef14 operon gene clusters in Salmonella pullorum

SEF14 fimbriae are only found in some strains of serogroup-D Salmonella such as S. enteritidis, suggesting that SEF14 fimbriae may affect serovar-specific virulence traits. In this study, we found that prevalence of sefA, sefD and sefR genes in S. dublin and S. enteritidis was 100%. In 18 isolates of S. pullorum, the prevalence of sefA gene was 100%, while the prevalence of sefD and sefR genes was 38.9% (7/18), and 11 strains isolated after 1980s did not contain any gene sefD or sefR. Interestingly, among the 7 strains of S. pullorum before 1980s, the sefD sequence has a missing base pair at position 196 and caused open reading frame (ORF) shift, resulting in a stop codon (TAG) at position 71 amino acid residual (Leu of TTA at position 214-216 shift into stop codon of TAG at position 215-217). Unlike S. pullorum, all S. enteritidis and S. dublin tested could express SEF14 fimbriae in vitro.

Genetic engineering of avian pathogenic E. coli to study the functions of FimH adhesin

Adhesion of pathogen to host cells is an important prerequisite for successful colonization and establishment of the pathogenesis. The aim of this study is to examine the function of FimH adhesin in the adherence of avian pathogenic E. coli to porcine intestinal epithelial cell lines (IPEC-J2) and human lung epithelial cell line (A549) in an in vitro infection model. Three strains of avian pathogenic Escherichia coli (APEC) and one strain of non-pathogenic E coli were used. The isogenic FimH mutants were constructed by lambda Red-mediated recombination system. The wild types and mutants strains were adhered to the host cells with different adherence patterns in certain incubation time. The results demonstrated that the adherence of the isogenic FimH mutants to the porcine intestinal epithelial cells (IPEC-J2) were similar to those of wild types. However, the adherences of isogenic FimH mutants to human lung epithelial cells (A549) were significantly different from the wild types. A549 cell can be used as a type of cell model for colonization of the chicken extraintestinal. FimH offers a unique opportunity to investigate the role of the strength of adhesion independently from the many other factors that may affect surface colonization.

Expression of AP-2 alpha in SV40 immortalized human lung fibroblasts is associated with a distinct pattern of cytosine methylation in the AP-2 alpha promoter

Activator protein-2 alpha (AP-2 alpha) is a cell type-specific, developmentally regulated, transcription factor that has been implicated as a critical regulator of gene expression during vertebrate development and carcinogenesis. We found that AP-2 alpha was differentially expressed in the normal human lung fibroblast cell strains WI38, MRC-5 and their respective SV40-transformed cell counterparts WI38-VA, MRC-5VA. Since CpG methylation within genetic regulatory regions has been implicated as a mechanism of gene regulation, we investigated the CpG methylation status of the AP-2 alpha gene promoter in these cells. High resolution mapping of methylated cytosines revealed that differential expression of the AP-2 alpha gene in normal human lung fibroblasts and their SV40-transformed counterparts was associated with distinct patterns of cytosine methylation in the AP-2 alpha promoter just 5' to the transcription initiation site. Site-specific methylation was positively correlated with increased AP-2 alpha gene expression in both transformed cell lines investigated. Interestingly, one of the two major centers of hypermethylation in the transformed cells encompassed the cis-element for the AP-2 repressing transcription factor AP-2rep (KLF12). Finally, a sequence variation in human lung fibroblasts relative to the published sequence revealed a previously unidentified AP-2 binding site at position -528 with respect to the transcription initiation site that overlapped the AP-2rep site. Our results suggest that transcriptional activation of AP-2 alpha in the SV40-transformed cells is mediated, at least in part, by site-specific methylation of a negative regulatory cis-element in the AP-2 alpha promoter.

A family of AP-2 proteins down-regulate manganese superoxide dismutase expression

Manganese superoxide dismutase (Mn-SOD) is a primary antioxidant enzyme whose expression is essential for life in oxygen. Mn-SOD has tumor suppressor activity in a wide variety of tumors and transformed cell systems. Our initial observations revealed that Mn-SOD expression was inversely correlated with expression of AP-2 transcription factors in normal human fibroblasts and their SV-40 transformed counterparts. Thus we hypothesized that AP-2 may down-regulate Mn-SOD expression. To examine the functional role of AP-2 on Mn-SOD promoter transactivation we cotransfected AP-2-deficient HepG2 cells with a human Mn-SOD promoter-reporter construct and expression vectors encoding each of the three known AP-2 family members. Our results indicated that AP-2 could significantly repress Mn-SOD promoter activity, and that this repression was both Mn-SOD promoter and AP-2-specific. The three AP-2 proteins appeared to play distinct roles in Mn-SOD gene regulation. Moreover, although all three AP-2 proteins could repress the Mn-SOD promoter, AP-2alpha and AP-2gamma were more active in this regard than AP-2beta. Transcriptional repression by AP-2 was not a general effect in this system, because another AP-2-responsive gene, c-erbB-3, was transactivated by AP-2. Repression of Mn-SOD by AP-2 was dependent on DNA binding, and expression of AP-2B, a dominant negative incapable of DNA binding, relieved the repression on Mn-SOD promoter and reactivated Mn-SOD expression in the AP-2 abundant SV40-transformed fibroblast cell line MRC-5VA. These results indicate that AP-2-mediated transcriptional repression contributes to the constitutively low expression of Mn-SOD in SV40-transformed fibroblasts and suggest a mechanism for Mn-SOD down-regulation in cancer.

Localization of cholecystokinin-octapeptide-like-immunoreactivity in neurons cultured from rat cerebral cortex

Cholecystokinin-octapeptide-like-immunoreactivity (CCK-8-LI) is demonstrable by the indirect immunofluorescent technique in cerebral cortical neurons cultured from fetal rats. Prominent and widespread staining is seen in widely ramifying cellular processes throughout the cultures. Staining in neuronal cell bodies is enhanced by treatment of the cultures with colchicine prior to fixation and can be seen to extend from the perikaryal region into dendrites and axonal processes. While several morphological types of neurons contain CCK-8-LI, there is a relative preponderance of small and moderate-sized bipolar and, to a lesser extent, multipolar neurons. These findings are in concordance with the findings of several investigators in studies of brain sections. The further finding of frequent groupings of CCK-8 neurons is noted and discussed.

Coexistence of acetylcholinesterase and somatostatin-immunoreactivity in neurons cultured from rat cerebrum

Cultures derived from rat cerebral hemispheres were sequentially stained for acetylcholinesterase activity and for either somatostatin-like immunoreactivity or cholecystokinin-like immunoreactivity. Somatostatin-like immunoreactivity was found to coexist with acetylcholinesterase activity in individual neurons of several morphological subtypes, but cholecystokinin-like immunoreactivity and acetycholinesterase activity were never seen in the same neurons. These findings suggest a specific anatomical association, perhaps even an overlap, of the cholinergic and somatostatinergic systems in the mammalian cerebrum, and indicate that the combined deficiencies of somatostatin and cholinergic markers in Alzheimer's dementia and senile dementia of the Alzheimer type may be of pathophysiological importance.