Dual-Track Multifunctional Bimetallic Metal-Organic Frameworks for Antibiotic Enrichment and Detection

The improper use and overuse of antibiotics have led to significant burdens and detrimental effects on the environment, food supply, and human health. Herein, a magnetic solid-phase extraction program and an optical immunosensor based on bimetallic Ce/Zr-UiO 66 for the detection of antibiotics are developed. A magnetic Fe3O4@SiO2@Ce/Zr-UiO 66 metal-organic framework (MOF) is prepared to extract and enrich chloramphenicol from fish, wastewater, and urine samples, and a horseradish peroxidase (HRP)-Ce/Zr-UiO 66@bovine serum protein-chloramphenicol probe is used for the sensitive detection of chloramphenicol based on the dual-effect catalysis of Ce and HRP. In this manner, the application of Ce/Zr-UiO 66 in integrating sample pretreatment and antibiotic detection is systematically investigated and the associated mechanisms are explored. It is concluded that Ce/Zr-UiO 66 is a versatile dual-track material exhibiting high enrichment efficiency (6.37 mg g-1) and high sensitivity (limit of detection of 51.3 pg mL-1) for chloramphenicol detection and serving as a multifunctional MOF for safeguarding public health and hygiene.

Mesophilic Argonaute-Mediated Polydisperse Droplet Biosensor for Amplification-Free, One-Pot, and Multiplexed Nucleic Acid Detection Using Deep Learning

Detection of nucleic acids from a single multiplexed and amplification-free test is critical for ensuring food safety, clinical diagnostics, and environmental monitoring. In this study, we introduced a mesophilic Argonaute protein from Clostridium butyricum (CbAgo), which exhibits nucleic acid endonuclease activity, to achieve a programmable, amplification-free system (PASS) for rapid nucleic acid quantification at ambient temperatures in one pot. By using CbAgo-mediated binding with specific guide DNA (gDNA) and subsequent targeted cleavage of wild-type target DNAs complementary to gDNA, PASS can detect multiple foodborne pathogen DNA (<102 CFU/mL) simultaneously. The fluorescence signals were then transferred to polydisperse emulsions and analyzed by using deep learning. This simplifies the process and increases the suitability of polydisperse emulsions compared to traditional digital PCR, which requires homogeneous droplets for accurate detection. We believe that PASS has the potential to become a next-generation point-of-care digital nucleic acid detection method.

Artificial Intelligence-Based Imaging Transcoding System for Multiplex Screening of Viable Foodborne Pathogens

Multiplex detection of viable foodborne pathogens is critical for food safety and public health, yet current assays suffer trade-offs between cost, assay complexity, sensitivities, and the specificity between live and dead bacteria. We herein developed a sensing method using artificial intelligence transcoding (SMART) for rapid, sensitive, and multiplex profiling of foodborne pathogens. The assay utilizes the programmable polystyrene (PS) microspheres to encode different pathogens, inducing subsequent visible signals under conventional microscopy that can be analyzed using a customized, artificial intelligence-computer vision, which was trained to decode the intrinsic properties of PS microspheres to reveal the numbers and types of pathogens. Our approach enabled the rapid and simultaneous detection of multiple bacteria from egg samples of <10² CFU/mL without DNA amplification and showed strong consistency with the standard microbiologic and genotypic methods. We adopted our assay through phage-guided targeting to enable the discrimination between live and dead bacteria.

Polystyrene microsphere-mediated optical sensing strategy for ultrasensitive determination of aflatoxin M1 in milk

Aflatoxin M₁ (AFM₁) contamination poses a serious threat to human health globally. Hence, it is necessary to develop reliable and ultrasensitive methods for the determination of AFM₁ residue in food products at low levels. In this study, a novel polystyrene microsphere-mediated optical sensing (PSM-OS) strategy was constructed to solve the problems of low sensitivity and susceptibility to interference from the matrix in AFM₁ determination. Polystyrene (PS) microspheres have the advantages of low cost, high stability, and controllable particle size. They can be useful optical signal probes for qualitative and quantitative analyses attributed to the fact that they have strong ultraviolet-visible (UV-vis) characteristic absorption peaks. Briefly, magnetic nanoparticles were modified with the complex of bovine serum protein and AFM₁ (MNP₁₅₀-BSA-AFM₁), and biotinylated antibodies of AFM₁ (AFM₁-Ab-Bio). Meanwhile, PS microspheres were also functionalized with streptavidin (SA-PS₉₅₀). In the presence of AFM₁, a competitive immune reaction was triggered leading to the changes in AFM₁-Ab-Bio concentrations on the surface of MNP₁₅₀-BSA-AFM₁. The complex of MNP₁₅₀-BSA-AFM₁-Ab-Bio binds with SA-PS₉₅₀ to form the immune complexes due to the special binding of biotin and streptavidin. The remaining SA-PS₉₅₀ in the supernatant was determined by UV-Vis spectrophotometer after magnetic separation, which positively correlated with the concentration of AFM₁. This strategy allows for ultrasensitive determination of AFM₁ with limits of detection as low as 3.2 pg/mL. It was also successfully validated for AFM₁ determination in milk samples, and a high consistency was found with the chemiluminescence immunoassay. Overall, the proposed PSM-OS strategy can be used for the rapid, ultrasensitive, and convenient determination of AFM₁, as well as other biochemical analytes.

[IRE1α deficiency impairs autophagy in chondrocytes by upregulating calcium homeostasis endoplasmic reticulum protein]

OBJECTIVE

To explore the mechanism by which inositol-requiring enzyme-1α (IRE1α) regulates autophagy function of chondrocytes through calcium homeostasis endoplasmic reticulum protein (CHERP).

METHODS

Cultured human chondrocytes (C28/I2 cells) were treated with tunicamycin, 4μ8c, rapamycin, or both 4μ8c and rapamycin, and the expressions of endoplasmic reticulum (ER) stress- and autophagy-related proteins were detected with Western blotting. Primary chondrocytes from ERN1 knockout (ERN1 CKO) mice and wild-type mice were examined for ATG5 and ATG7 mRNA expressions, IRE1α and p-IRE1α protein expressions, and intracellular calcium ion content using qPCR, Western blotting and flow cytometry. The effect of bafilomycin A1 treatment on LC3 Ⅱ/LC3 Ⅰ ratio in the isolated chondrocytes was assessed with Western blotting. Changes in autophagic flux of the chondrocytes in response to rapamycin treatment were detected using autophagy dual fluorescent virus. The changes in autophagy level in C28/I2 cells overexpressing CHERP and IRE1α were detected using immunofluorescence assay.

RESULTS

Tunicamycin treatment significantly up-regulated ER stress-related proteins and LC3 Ⅱ/LC3 Ⅰ ratio and down-regulated the expression of p62 in C28/I2 cells (P < 0.05). Rapamycin obviously up-regulated LC3 Ⅱ/LC3 Ⅰ ratio (P < 0.001) in C28/I2 cells, but this effect was significantly attenuated by co-treatment with 4μ8c (P < 0.05). Compared with the cells from the wild-type mice, the primary chondrocytes from ERN1 knockout mice showed significantly down-regulated mRNA levels of ERN1 (P < 0.01), ATG5 (P < 0.001) and ATG7 (P < 0.001), lowered or even lost expressions of IRE1α and p-IRE1α proteins (PP < 0.01), and increased expression of CHERP (P < 0.05) and intracellular calcium ion content (P < 0.001). Bafilomycin A1 treatment obviously increased LC3 Ⅱ/ LC3 Ⅰ ratio in the chondrocytes from both wild-type and ERN1 knockout mice (P < 0.01 or 0.05), but the increment was more obvious in the wild-type chondrocytes (P < 0.05). Treatment with autophagy dual-fluorescence virus resulted in a significantly greater fluorescence intensity of LC3-GFP in rapamycin-treated ERN1 CKO chondrocytes than in wild-type chondrocytes (P < 0.05). In C28/I2 cells, overexpression of CHERP obviously decreased the fluorescence intensity of LC3, and overexpression of IRE1α enhanced the fluorescence intensity and partially rescued the fluorescence reduction of LC3 caused by CHERP.

CONCLUSION

IRE1α deficiency impairs autophagy in chondrocytes by upregulating CHERP and increasing intracellular calcium ion content.

Click Chemistry-Mediated Particle Counting Sensing via Cu(II)-Polyglutamic Acid Coordination Chemistry and Enzymatic Reaction

An electrical resistance-based particle counter (ERPC) with simple operation and high resolution has proved to be a promising biosensing toolkit, whereas amplification-free ERPC biosensors are incapable of analyzing trace small molecules due to their relatively low sensitivity. In this work, click chemistry-mediated particle counting sensing of small-molecule hazards in food samples with high sensitivity was developed. In this strategy, unbound alkyne-functionalized polystyrene microspheres were collected by magnetic separation from the copper-ion-mediated click reaction between alkyne-functionalized polystyrene microspheres and azido-functionalized magnetic beads, which could be used as signal probes for the readout. This click chemistry-mediated ERPC biosensor converts the detection of targets to the quantification of copper ions or ascorbic acid by performing competitive immunoassay-based coordination chemistry and enzymatic reaction, respectively. The sensitivity of the ERPC biosensor has been improved by an order of magnitude due to the signal amplification effects of click chemistry, coordination adsorption, and enzyme catalysis. Furthermore, because of the efficient separation and enrichment of immunomagnetic beads and the robustness of click chemistry, the interference from food matrixes and immunoassay is effectively reduced, and thus, our strategy is exceedingly suitable for detecting trace targets in complex samples.

Correlation between the Polymorphism of Coagulation-Related Genes and Lower Extremity Deep Venous Thrombosis

Abstract

Objective To investigate the correlation between the polymorphism of 4 coagulation-related genes, rs1799963 （coagulation factor V gene Leiden）, rs6025 （prothrombin gene G20210A）, rs1042579 （thrombomodulin protein gene c.1418C>T） and rs1801131 （methylenetetrahydroflate reductase gene） and lower extremity deep venous thrombosis （LEDVT）. Methods The 4 genotypes mentioned above of 150 LEDVT patients and 153 healthy controls were detected by the kompetitive allele specific polymerase chain reaction （KASP）, then related blood biochemical indicators were collected, binary Logistic regression was established to screen the independent risk factors of LEDVT, and the correlation between polymorphism of 4 coagulation-related genes and LEDVT and its indicators under different genetic modes after adjusting confounding factors were analyzed. Results Five variables, D-dimer, fibrinogen degradation product, homocysteine, sex and age might be the risk factors of LEDVT. These variables were put into 4 genetic inheritance models, and adjusted in binary Logistic regression. The results suggested that the mutations of rs1042579 were correlated with LEDVT under dominant inheritance mode. Conclusion The gene polymorphism of rs1799963, rs6025 and rs1801131 has no significant correlation with the formation of LEDVT. The gene polymorphism of rs1042579 plays a role under dominant inheritance mode, and might be an independent risk factor for formation of LEDVT.

[Two cases of occupational frostbite]

The diagnosis, treatment, operation and diagnosis of two cases of occupational frostbite diagnosed in Shandong Academy of Occupational Healthy Occupational Medicine were analyzed retrospectively. In these two patients working in a low temperature environment, the finger frostbite did not arouse enough attention, one patient did not receive timely diagnosis and treatment, and one patient received timely medical treatment, but did not receive proper treatment, which ultimately led to the adverse consequences of finger amputation. The staff under the low temperature environment should strictly carry out the low temperature operation protection standard and improve their self-protection consciousness. If frostbite occurs, they should seek medical treatment in time, which can effectively reduce the disability rate.

Serological surveillance of avian influenza virus and canine distemper virus in captive Siberian Tigers in Northeastern China

In order to understand infection of avian influenza A virus (AIV) and canine distemper virus (CDV) in the Siberian Tiger in Northeast China, 75 Siberian Tiger serum samples from three cap- tive facilities in northeastern China were collected. AIV and CDV antibody surveillance was test- ed by using hemagglutination inhibition and serum neutralization methods. The results showed that the seroprevalence of H5 AIV, H9 AIV and CDV was respectively 9.33% (7/75), 61.33% (46/75) and 16% (12/75). In the 1⟨years ⟨2 and > 5 year-old group, the seroprevalence of the H9 AIV was 24% and 80% (P ⟨ 0.01), and the CDV seroprevalence was 6% and 36% (P ⟨ 0.01), respectively. It was demonstrated that 3 (4%) out of 75 serum samples were AIV+CDV seropos- itive, with 2.67% (2/75) in H9+AIV and 1.33% (1/75) in H5+H9+AIV. To our knowledge, this is the first report of AIV and CDV seroprevalence in Siberian Tigers in China, which will provide base-line data for the control of AIV and CDV infection in Siberian Tigers in China.

[Prevalence and associated risk factors on preterm birth, low birth weight, and small for gestational age among HIV-infected pregnant women in Hunan province, 2011-2017]

Objective: To describe the prevalence of preterm birth (PB), low birth weight (LBW), and small for gestational age (SGA) among HIV-infected pregnant women and to identify associated risk factors in Hunan province. Methods: This study appeared a retrospective one on HIV-infected pregnant women retrieved from Information System of Prevention of Mother-to-child Transmission of HIV management in Hunan province, between January 2011 and December 2017. Information regarding demographic characteristics, pregnancy, antiretroviral therapy (ART), husbands/partners' relevant situation and pregnancy outcomes, among these HIV-infected pregnant women were collected and analyzed. The incidence rates on PB, LBW and SGA were calculated. Multivariate logistic regression was used to analyze the associated risk factors. Results: A total of 780 HIV-infected pregnant women were enrolled. The prevalence rates on PB, LBW and SGA in HIV- infected pregnant women appeared as 7.9% (62/780), 9.9% (77/780) and 21.3% (166/780), respectively. Results from the multivariate logistic regression analysis showed that factors as pregnancy related diseases as moderate/severe anemia, hypertensive, initial time of ART <14 gestational weeks (compared to those women without ART during pregnancy) and husbands/partners' age >35 years old (compared to husbands/partners' age 26-30 years old) etc., were associated with an increased risk of PB with adjusted OR as 4.59 (95%CI: 1.51-13.95), 4.90 (95%CI: 1.56-15.46), 2.40 (95%CI: 1.26- 4.56) and 2.29 (95%CI: 1.21-4.36). For LBW, pregnancy moderate/severe anemia, pregnancy HBV infection and initial time of ART <14 gestational weeks were associated with an increased risk of LBW, with adjusted OR as 3.28 (95%CI: 1.13-9.54), 4.37 (95%CI: 1.42-13.44) and 2.68 (95%CI: 1.51-4.76), respectively. For SGA, pregnancy HBV infection and initial time of ART <14 gestational weeks were risk factors for SGA, with adjusted OR as 4.41 (95%CI: 1.43-13.63) and 2.67 (95%CI: 1.51-4.73), respectively. Conclusion: Preterm birth, LBW and SGA were common adverse pregnancy outcomes for HIV-infected pregnant women and were associated with factors as pregnancy complications, ART and husbands/partners' age.

CYP3A4 gene polymorphism is correlated with individual consumption of sufentanil

BACKGROUND

Pain is one of the major adverse clinical outcomes of cesarean section (CS). In the past few years, researchers and physicians have been optimizing post-operative analgesic modalities, but the results are still undesirable for the parturient. The cytochrome P-450 3A4 (CYP3A4) gene has been reported to contribute significantly to human liver microsomal oxidation of sufentanil and alfentanil.

METHODS

We detected the frequency of CYP3A4 mutant allele, which is associated with the metabolism of diverse drugs, including opioids used for anesthesia. We then investigated the correlation between sufentanil (an opioid analgesic) consumption and CYP3A4 genetic polymorphism.

RESULTS

We found the frequency of the CYP3A4∗1G (the mutant form of CYP3A) variant allele to be 0.279 in 71 parturients undergoing cesarean section and 137 age-matched parturients with vaginal delivery. Interestingly, the parturients with homozygous CYP3A4∗1G showed less sufentanil consumption compared with those having the wild-type genotype.

CONCLUSION

In summary, we found a correlation between CYP3A4 genetic polymorphism and sufentanil consumption. This might be helpful for optimizing the anesthesia strategies and reducing their side effects.

Oxytocin receptor mRNA expression in dorsolateral prefrontal cortex in major psychiatric disorders: A human post-mortem study

There is growing interest in oxytocin as a putative treatment for various psychiatric disorders including major depressive disorder, bipolar disorder and schizophrenia/schizoaffective disorder. However, potential alterations in the endogenous brain oxytocin system in these disorders are poorly characterized. Brain expression of oxytocin and its receptor genes in patients with these psychiatric disorders has not been well studied outside the hypothalamus. We measured expression of mRNA for oxytocin and its receptor in the dorsolateral prefrontal cortex of postmortem brains using quantitative polymerase chain reaction in a total of 581 individuals. These individuals either were diagnosed with major depressive disorder (n = 135), bipolar disorder (n = 57), schizophrenia/schizoaffective disorder (n = 169), or were control subjects, defined as individuals with no lifetime history of any of these disorders (n = 220). Diagnoses of major depressive disorder and bipolar disorder were associated with significantly increased oxytocin receptor mRNA levels in the dorsolateral prefrontal cortex. This finding is discussed in light of the extant literature on the dysregulation of oxytocin signaling in individuals with major psychiatric disorders.

[Nested case-control study on associated factors for anemia during pregnancy]

Objective: To explore the related factors of anemia during pregnancy and provide scientific evidence for the primary prevention of anemia during pregnancy. Methods: The pregnant women (≤12 pregnant weeks) who received the first pregnancy care in a local medical institution in Hunan province from June 2013 to November 2014 were included in this cohort study, and for them anemia had been excluded by physical examination. Baseline survey and follow up till childbirth were conducted for them. A queue-based nested case-control study (1 ∶ 2) was conducted (380 pregnant women with anemia detected in this study as case group, 760 pregnant women without anemia randomly selected and matched by age, habitual residence during pregnancy as control group. And t test, χ(2) test and logistic regression analysis were conducted to identify related factors of anemia during pregnancy. Results: Multivariate logistic regression analysis indicated that low family annual income level (net income) (OR=2.08, 95%CI: 1.22-3.59), low educational level (OR=2.09, 95%CI: 1.22-3.59), pre-pregnancy perm/hair dye (OR=2.23, 95%CI: 1.63-3.05), early pregnancy vomiting (OR=2.51, 95%CI: 1.56-4.03) were the risk factors for anemia during pregnancy. Intake of vitamin and trace element supplements (OR=0.69, 95%CI: 0.50-0.94), frequent meat, fish, shrimp, egg intakes (OR=0.68, 95%CI: 0.49-0.92), frequent soy milk, milk intakes (OR=0.51, 95%CI: 0.27-0.95) were the protective factors for anemia during pregnancy. Conclusion: A number of factors, such as family annual income level, education level, poisonous and harmful material contact, pregnancy reaction, nutrition, are related to the incidence of anemia during pregnancy, it is necessary to take preventive measures to reduce the incidence of anemia during pregnancy.

Association between folate status and cervical intraepithelial neoplasia

Background/Objectives:

To investigate the effect of folate status on cervical intraepithelial neoplasia (CIN) progression and its relationship with high-risk human papillomavirus (hrHPV).

Subjects/Methods:

We evaluated 20 000 sexually active women aged <65 years in Yangqu County by using a questionnaire; the subjects were also screened using the ThinPrep cytologic test (TCT). Patients with abnormal TCT results (other than glandular cell abnormalities) who were willing to provide informed consent were further diagnosed using colposcopy and histopathological examination. We investigated 247 cases of low-grade cervical squamous intraepithelial lesions (LSIL), 125 cases of high-grade cervical squamous intraepithelial lesions (HSIL) and 877 controls. A 24-item food frequency questionnaire was filled out by the investigator to estimate the consumption of dietary folate. Positivity for hrHPV from residual exfoliated cervical cells was tested; serum folate was also measured.

Results:

The hrHPV infection rate in HSIL patients (77.6%) was higher than that in LSIL (33.2%) and control (32.0%) patients. Dietary folate intakes in controls, LSIL and HSIL were 306.9±176.6, 321.8±168.0 and 314.7±193.8 μg/kcal, respectively. The levels of serum folate in controls, LSIL and HSIL were 18.2±7.9, 15.9±7.1 and 14.3±7.5 nmol/l, respectively. Increased CIN correlated with higher rates of hrHPV infection and lower levels of serum folate.

Conclusions:

Low levels of serum folate may increase the risk of CIN progression. Furthermore, potential synergy may exist between low serum folate levels and hrHPV infection to promote CIN development.

The Kinematics and Kinetics Analysis of the Lower Extremity in the Landing Phase of a Stop-jump Task

Large number of studies showed that landing with great impact forces may be a risk factor for knee injuries. The purpose of this study was to illustrate the different landing loads to lower extremity of both genders and examine the relationships among selected lower extremity kinematics and kinetics during the landing of a stop-jump task. A total of 35 male and 35 female healthy subjects were recruited in this study. Each subject executed five experiment actions. Lower extremity kinematics and kinetics were synchronously acquired. The comparison of lower extremity kinematics for different genders showed significant difference. The knee and hip maximum flexion angle, peak ground reaction force and peak knee extension moment have significantly decreased during the landing of the stop-jump task among the female subjects. The hip flexion angle at the initial foot contact phase showed significant correlation with peak ground reaction force during landing of the stop-jump task (r=-0.927, p<0.001). The knee flexion angle at the initial foot contact phase had significant correlation with peak ground reaction force and vertical ground reaction forces during landing of the stop-jump task (r=-0.908, p<0.001; r=0.812, P=0.002). A large hip and knee flexion angles at the initial foot contact with the ground did not necessarily reduce the impact force during landing, but active hip and knee flexion motions did. The hip and knee flexion motion of landing was an important technical factor that affects anterior cruciate ligament (ACL) loading during the landing of the stop-jump task.

[Application of three-diinensional CT in the treatment of oblique facial clefts with mandibular outer cortex]

OBJECTIVE

To investigate the application of three-dimensional CT(3D-CT) in the treatment of oblique facial clefts with mandibular outer cortex, including the surgical design and results assessment.

METHODS

From Jan. 2003 to Dec. 2013, 22 cases with oblique facial cleft, who underwent mandibular outer cortex onlay bone graft were retrospectively studied. 3D images from CT data were reconstructed before operation for design. Then the mandibular outer cortex onlay bone transplant was performed to reconstruct the bone defect and cleft. 3D CT was performed 5-10 days postoperatively and 6- 12 months postoperatively to assess the facial symmetry.

RESULTS

According to the results of CT measurement, the average volume of the orbital bone defects on the affected side decreased by(64. 6 ± 14. 4)% 5 to 10 days after operation. The average volume of the maxillary and zygomatic bone defects on the affected side decreased by(71.4 ± 15.7)% after surgery. After 6 to 12 months,the average recovery of the mandibular donor site was (57. 9 ± 13. 9)% of the removed mandibular outer cortex. The average absorption of grafted bones was(24.7 ± 25.6 )%. The average height difference between the centre of pupils on both sides before surgery was(3.76 ± 1.27) mm,which decreased to( 1. 15 ± 1.00) mm 5 to 10 days after surgery(P =0. 000) , and( 1.35 ± 1. 13) mm 6 to 12 months after surgery(P = 0. 003). The relapse may be caused by the absorption of the grafted bones.

CONCLUSIONS

3D-CT can be used for preoperative design and postoperative assessment in the treatment of oblique facial cleft with mandibular outer cortex.

A pilot study of endoscopic spray cryotherapy by pressurized carbon dioxide gas for Barrett's esophagus

BACKGROUND AND STUDY AIMS

Endoscopic spray cryoablation is a novel approach for the treatment of Barrett's esophagus. However, few studies have reported its efficacy, especially with the use of carbon dioxide (CO (2)). The aim of the current study was to evaluate the short term efficacy and complications using CO (2) in endoscopic cryoablation of Barrett's esophagus.

METHODS

Patients diagnosed with Barrett's esophagus underwent monthly stepwise cryoablation with pressurized CO (2) gas, with follow-up esophageal biopsies until complete histological reversal was achieved. Responses were analyzed with an intention-to-treat analysis according to complete response for intestinal metaplasia (CR-IM), which was defined as the elimination of all intestinal metaplasia including specialized intestinal metaplasia (SIM), subsquamous SIM, and dysplasia with intestinal metaplasia in the biopsies under narrow-band imaging (NBI).

RESULTS

In total, 22 patients were enrolled, 20 of whom completed the treatment. Two patients declined further ablation after the first cryotherapy session. A total of 44 sessions were performed; a median of 2 sessions per patient (range 1 - 3 sessions) were needed to complete the ablation of Barrett's esophagus. No severe complications occurred. Follow-up endoscopies were performed in 20 patients (90.9 %). Two patients (9.1 %) were lost to follow-up. Median follow-up was 10 months (range 6 - 18 months). After cryotherapy, 20 patients (90.9 %) reached CR-IM of Barrett's esophagus. Patients underwent a median number of 3 follow-up endoscopies (range 2 - 4) with biopsies. At 6 months, recurrence was evident in three patients (13.6 % of the overall population, 15.0 % of the CR-IM population). One of the three patients developed intestinal metaplasia but no dysplastic change and the other two developed subsquamous SIM.

CONCLUSIONS

The pressurized CO (2) spray cryotherapy is a relatively effective and safe endoscopic treatment for Barrett's esophagus.

Role of interferon in homologous and heterologous rotavirus infection in the intestines and extraintestinal organs of suckling mice

Recent studies demonstrated that viremia and extraintestinal rotavirus infection are common in acutely infected humans and animals, while systemic diseases appear to be rare. Intraperitoneal infection of newborn mice with rhesus rotavirus (RRV) results in biliary atresia (BA), and this condition is influenced by the host interferon response. We studied orally inoculated 5-day-old suckling mice that were deficient in interferon (IFN) signaling to evaluate the role of interferon on the outcome of local and systemic infection after enteric inoculation. We found that systemic replication of RRV, but not murine rotavirus strain EC, was greatly enhanced in IFN-alpha/beta and IFN-gamma receptor double-knockout (KO) or STAT1 KO mice but not in mice deficient in B- or T-cell immunity. The enhanced replication of RRV was associated with a lethal hepatitis, pancreatitis, and BA, while no systemic disease was observed in strain EC-infected interferon-deficient mice. In IFN-alpha/beta receptor KO mice the extraintestinal infection and systemic disease were only moderately increased, while RRV infection was not augmented and systemic disease was not present in IFN-gamma receptor KO mice. The increase of systemic infection in IFN-deficient mice was also observed during simian strain SA11 infection but not following bovine NCDV, porcine OSU, or murine strain EW infection. Our data indicate that the requirements for the interferon system to inhibit intestinal and extraintestinal viral replication in suckling mice vary among different heterologous and homologous rotavirus strains, and this variation is associated with lethal systemic disease.

Cholinergic neurons of mouse intrinsic cardiac ganglia contain noradrenergic enzymes, norepinephrine transporters, and the neurotrophin receptors tropomyosin-related kinase A and p75

Half of the cholinergic neurons of human and primate intrinsic cardiac ganglia (ICG) have a dual cholinergic/noradrenergic phenotype. Likewise, a large subpopulation of cholinergic neurons of the mouse heart expresses enzymes needed for synthesis of norepinephrine (NE), but they lack the vesicular monoamine transporter type 2 (VMAT2) required for catecholamine storage. In the present study, we determined the full scope of noradrenergic properties (i.e. synthetic enzymes and transporters) expressed by cholinergic neurons of mouse ICG, estimated the relative abundance of neurons expressing different elements of the noradrenergic phenotype, and evaluated the colocalization of cholinergic and noradrenergic markers in atrial nerve fibers. Stellate ganglia were used as a positive control for noradrenergic markers. Using fluorescence immunohistochemistry and confocal microscopy, we found that about 30% of cholinergic cell bodies contained tyrosine hydroxylase (TH), including the activated form that is phosphorylated at Ser-40 (pSer40 TH). Dopamine beta-hydroxylase (DBH) and norepinephrine transporter (NET) were present in all cholinergic somata, indicating a wider capability for dopamine metabolism and catecholamine uptake. Yet, cholinergic somata lacked VMAT2, precluding the potential for NE storage and vesicular release. In contrast to cholinergic somata, cardiac nerve fibers rarely showed colocalization of cholinergic and noradrenergic markers. Instead, these labels were closely apposed but clearly distinct from each other. Since cholinergic somata expressed several noradrenergic proteins, we questioned whether these neurons might also contain trophic factor receptors typical of noradrenergic neurons. Indeed, we found that all cholinergic cell bodies of mouse ICG, like noradrenergic cell bodies of the stellate ganglia, contained both tropomyosin-related kinase A (TrkA) and p75 neurotrophin receptors. Collectively, these findings demonstrate that mouse intrinsic cardiac neurons (ICNs), like those of humans, have a complex neurochemical phenotype that goes beyond the classical view of cardiac parasympathetic neurons. They also suggest that neurotrophins and local NE synthesis might have important effects on neurons of the mouse ICG.

Extraintestinal spread and replication of a homologous EC rotavirus strain and a heterologous rhesus rotavirus in BALB/c mice

Although rotavirus infection has generally been felt to be restricted to the gastrointestinal tract, over the last two decades there have been sporadic reports of children with acute or fatal cases of rotavirus gastroenteritis testing positive for rotavirus antigen and/or nucleic acid in various extraintestinal locations such as serum, liver, kidney, bladder, testes, nasal secretions, cerebrospinal fluid, and the central nervous system. Recently, studies in animals and people have demonstrated that rotavirus antigenemia is a common event during natural infection. In this study, we extend these observations and compare the intestinal and extraintestinal spread of wild-type homologous murine rotavirus EC and a heterologous strain, rhesus rotavirus (RRV), in newborn mice. A strand-specific quantitative reverse transcription-PCR (ssQRT-PCR) assay was used to quantify the ability of different rotavirus strains to spread and replicate extraintestinally. Both strain EC and RRV were detected extraintestinally in the mesenteric lymph nodes (MLN), livers, lungs, blood, and kidneys. Extraintestinal replication, as measured by ssQRT-PCR, was most prominent in the MLN and occurred to a lesser degree in the livers, kidneys, and lungs. In the MLN, strain EC and RRV had similar (P < 0.05) RNA copy numbers, although EC was present at a 10,000-fold excess over RRV in the small intestine. Rotavirus nonstructural protein 4 (NSP4) and/or assembled triple-layered particles, indicated by immunostaining with the VP7 conformation-dependent monoclonal antibody 159, were detected in the MLN, lungs, and livers of EC- and RRV-inoculated mice, confirming the ssQRT-PCR findings. Infectious RRV was detected in the MLN in quantities exceeding the amount present in the small intestines or blood. The cells in the MLN that supported rotavirus replication included dendritic cells and potentially B cells and macrophages. These data indicate that extraintestinal spread and replication occurs commonly during homologous and some heterologous rotaviral infections; that the substantial host range restrictions for rhesus rotavirus, a heterologous strain present in the intestine, are not necessarily apparent at systemic sites; that the level and location of extraintestinal replication varies between strains; that replication can occur in several leukocytes subsets; and that extraintestinal replication is likely a part of the normal pathogenic sequence of homologous rotavirus infection.

Corticotropin-releasing factor in the dorsal raphe elicits temporally distinct serotonergic responses in the limbic system in relation to fear behavior

The neurotransmitters serotonin and corticotrophin-releasing factor are thought to play an important role in fear and anxiety behaviors. This study aimed to determine the relationship between corticotrophin-releasing factor-evoked changes in serotonin levels within discrete regions of the limbic system and the expression of fear behavior in rats. The effects of corticotrophin-releasing factor administration to the serotonin cell body regions of the dorsal raphe nucleus on fear behavior, behavioral activity, and extracellular serotonin levels were assessed in freely moving rats with microdialysis probes implanted into the central nucleus of the amygdala and the medial prefrontal cortex. Infusion of corticotrophin-releasing factor (0.5 microg) into the dorsal raphe rapidly induced freezing behavior, which was positively correlated with an immediate increase in serotonin release in the central nucleus of the amygdala. In contrast, cessation of freezing behavior correlated with a delayed and prolonged increase in serotonin release within the medial prefrontal cortex. Our findings suggest that corticotrophin-releasing factor-induced freezing behavior is associated with regionally and temporally distinct serotonergic responses in the limbic system that may reflect differing roles for these regions in the expression of fear/anxiety behavior.

Associations between a polymorphism in the 11 beta hydroxysteroid dehydrogenase type I gene and body composition

We investigated 11 beta hydroxysteriod dehydrogenase type 1 (11betaHSD-1) sequence variants in 103 healthy overweight (BMI >2 s.d.) and 160 nonoverweight (BMI -2 to +2 SD) children to examine the associations between body composition and 11betaHSD-1 polymorphisms. A total of 4.3% of children were homozygous and 30.0% heterozygous for an adenine insertion in intron 3 (ins4436A). By ANCOVA (adjusting for age, sex, race, and height), BMI-s.d. differed according to ins4436A genotype (P<0.005), with the greatest BMI-SD for ins4436A homozygotes (mean +/-s.d., 3.4+/-3.4, vs heterozygotes, 0.8+/-5.5, or wild-type, 1.8+/-7.5). Homozygotes also had greater waist circumference, waist-to-hip ratio, and insulin resistance indices than heterozygote or wild-type children (all P<0.05), but no significant differences in trunk fat by DXA, or in serum lipids. We conclude an intronic 11betaHSD-1 gene polymorphism is associated with greater body mass, altered body composition, and insulin resistance in children. 11betaHSD-1 may be one of the genes relevant for pediatric-onset obesity and its complications.

[Gene polymorphism at apoB locus and the serum lipids profile in children]

The relations of gene polymorphism at the apolipoprotein B locus and serum lipid profile in children was studied in 308 normal 7-11 year-old children, including 151 boys and 157 girls. Blood samples were collected for all subjects, and then the serum and blood clot were separated. Serum lipids, including TC, TG, LDL-C, HDL-C, apoB, apoA I and Lp(a) were detected. Genome DNA was extracted from blood clot, then apoB-Xba I gene polymorphism were tested by PCR-RFLP method. The results showed that the distribution of apoB-Xba I genotype in 308 children accorded with Hardy-Weiberg inheritance equilibrium law. The frequency of heterozygote(+/-) was 13.3%, allele(+) was 0.067. The frequency of allele(+) was closed to the internal and Japanese reports (0.033 and 0.04), but much less than the Caucasians (0.50). This showed a ethnic and population difference in the inheritance variation. The average LDL-C levels of the heterozygotes(+/-) were 2.17 mmol/L, no difference compared with homozygotes(-/-) (2.21 mmol/L, P > 0.05). There was also no difference for the genotype distribution between the hyperlipidemia group and control group, which may be the results of no enough sample size and the sample selection, and so on. On the other hand, in normal children, serum lipids controlled by many genes, the effect of a single gene might be small. More studies and analysis on the relationship between serum lipids and multiple genes in multisites should be the next step.

[Relationship between gene polymorphism at the apolipoprotein E locus and serum lipid profile in urban children of school age in Beijing]

OBJECTIVE

To study the relationship between gene polymorphism at the apolipoprotein E (ApoE) locus and serum lipid levels in children of school age.

METHODS

Blood samples were collected from 307 normal children aged 7 to 11 years, including 150 boys and 157 girls, and their serum lipid profile, including total cholesterol (TC), triglyceride (TG), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol (HDL-C), apolipoprotein B(apoB), apoprotein A1 (ApoA I) and lipoptoein alpha[LP (alpha)], were detected and their ApoE-Hha I gene polymorphism were tested by the PCR-RFLP method.

RESULTS

The detection rates for the most frequent genotype ApoE3/3 was 54.7%, other genotypes E4/3, E4/4, E3/2, E4/2 and E2/2 were 23.8%, 9.1%, 8.1%, 3.9% and 0.3%, respectively, in 307 children, with no significant difference between girls and boys(P > 0.05). Frequency of the often seen allele E3 was 70.7%, and that of E4 and E2 was 23.0% and 6.4, respectively, with E4 significantly higher than and E2 similar to that in the other domestic reports. The levels of TC, LDL-C, ApoA I and ApoB were higher in boys with genotypes E4/3 and E3/3 than those with genotypes E3/2 and E4/2. Levels of TC and ApoA I in the boys with genotype E3/2 were higher, with TC of 4.28 mmol/L and ApoA I of 3.41 mmol/L. There were no significant difference in serum lipid levels of girls with different genotypes(P > 0.05). There also was no significant difference in the ApoE-Hha I genotype distribution between normal children and those with high TC. ApoE2 could decrease the level of TC by 0.377 mmol/L, and LDL-C by 0.329 mmol/L.

CONCLUSIONS

Serum level of TC associated with polymorphism of ApoE gene carrier in boys, with the lowest levels of TC, LDL-C and ApoE in three with allele E2.

Rotavirus assembly - interaction of surface protein VP7 with middle layer protein VP6

The interaction between the rotavirus proteins viral protein 6 (VP6) and VP7 was examined in several exogenous protein expression systems. These proteins associated in the absence of other rotaviral proteins as demonstrated by a coimmunoprecipitation assay. Deletion analysis of VP7 indicated that truncations of either the mature amino or carboxyl terminus disrupted the proper folding of the protein and were not able to coimmunoprecipitate VP6. Truncation analysis of VP6 indicated that trimerization of VP6 was necessary, but not sufficient, for VP7 binding. MAb mapping and coimmunoprecipitation interference assays indicate that the VP6 amino acid residues between 271 and 342 are required for VP7 interaction. The interaction of VP6 and VP7 was also examined by the assembly of soluble VP7 onto baculovirus-expressed virus-like particles containing VP2 and VP6. Abrogation of this binding by preincubation of the particles with VP6 MAbs mapped to this same domain of VP6, validated our coimmunoprecipitation results. VP6 IgA MAbs that have been shown to be protective in vivo, but not a nonprotective IgA MAb, can interfere with VP7 binding to VP6. This suggests that these IgA MAbs may protect against rotavirus infection by blocking rotavirus assembly.

Hypercholesterolemia alters vascular functions and gene expression of potassium channels in rat aortic smooth muscle cells

AIM

To investigate the effects of hypercholesterolemia on functions of rat aorta and on gene expression of inward rectifier and ATP-sensitive potassium channels in aortic smooth muscle.

METHODS

Rats were treated with high-cholesterol emulsion ig for 2 weeks; the aortic rings with and without endothelium were prepared to examine the aortic contractile and relaxation responses; RT-PCR was used to observe the gene expression of inward rectifier and ATP-sensitive potassium channels.

RESULTS

Hypercholesterolemia damaged the endothelium-dependent vascular functions severely, but did not affect the endothelium-independent vascular functions; Kir6.2 mRNA expression was upregulated (P < 0.05) and Kir3.1 mRNA expression was downregulated markedly (P < 0.05) in hypercholesterolemic smooth muscle.

CONCLUSION

Hypercholesterolemia altered the vascular functions and regulated gene expression levels of specific inward rectifier and ATP-sensitive potassium channel subtypes.

Protective intestinal anti-rotavirus B cell immunity is dependent on alpha 4 beta 7 integrin expression but does not require IgA antibody production

Rotavirus (RV) is the main cause of severe gastroenteritis in young children; protection has been correlated with intestinal Ab responses. Using a mouse model of RV infection and beta(7)-deficient (beta(7)(-/-)) mice, which do not express alpha(4)beta(7) integrin, we demonstrated the importance of alpha(4)beta(7) integrin in B cell-mediated anti-RV immunity. beta(7)(-/-) mice acutely infected with murine RV resolved infection and developed normal serum IgG Abs but had diminished intestinal IgA responses. alpha(4)beta(7)(-/-) immune B cells did not resolve RV infection when adoptively transferred into RV-infected Rag-2-deficient mice. Fewer RV-specific B cells were found in the intestine of Rag-2-deficient mice transferred with beta(7)(-/-) B cells compared with wild type. The absence of alpha(4)beta(7) expression and/or a lower frequency of IgA-producing cells among transferred beta(7)(-/-) B cells could have accounted for the inability of these cells to resolve RV infection following passive transfer. To distinguish between these possibilities, we studied the importance of IgA production in RV infection using IgA-deficient (IgA(-/-)) mice. IgA(-/-) mice depleted of CD8(+) T cells were able to clear primary RV infection. Similarly, adoptive transfer of immune IgA(-/-) B cells into chronically infected Rag-2-deficient mice resolved RV infection. We further demonstrated in both wild-type and IgA(-/-) mice that, following oral RV infection, protective B cells reside in the alpha(4)beta(7)(high) population. Our findings suggest that alpha(4)beta(7) integrin expression is necessary for B cell-mediated immunity to RV independent of the presence of IgA.

The binding ability analysis of the normal VLDL receptor and its mutant

The ligand-binding domain of VLDL receptor contains eight imperfectly similar repeats. To discuss the contribution of each repeat to ligand binding, the RT-PCR technique was used to clone the VLDLR-cDNA from the heart muscle of Chinese people. Two recombinants were further constructed, which contained the full-length cDNA of VLDLR and the mutant lacking repeats 1-5. CHO cell line was transfected with two recombinants. The expression of VLDLR gene could be detected by RT-PCR from the CHO cells transfected with pCD-VR. The results of binding experiments showed that the ability of the CHO cells transfected with the full-length cDNA of VLDL-R binding DiI-labeled beta-VLDL was higher than that of the CHO cells transfected with the mutant. Our findings indicated that human VLDL-R gene could be expressed effectively on CHO cells, and the receptor was almost inactivated when repeats 1-5 were deleted.

alpha(4)beta(7) independent pathway for CD8(+) T cell-mediated intestinal immunity to rotavirus

Rotavirus (RV), which replicates exclusively in cells of the small intestine, is the most important cause of severe diarrhea in young children worldwide. Using a mouse model, we show that expression of the intestinal homing integrin alpha(4)ss(7) is not essential for CD8(+) T cells to migrate to the intestine or provide immunity to RV. Mice deficient in ss7 expression (ss7(-/-)) and unable to express alpha(4)ss(7) integrin were found to clear RV as quickly as wild-type (wt) animals. Depletion of CD8(+) T cells in ss7(-/-) animals prolonged viral shedding, and transfer of immune ss7(-/-) CD8(+) T cells into chronically infected Rag-2-deficient mice resolved RV infection as efficiently as wt CD8(+) T cells. Paradoxically, alpha(4)ss(7)(hi) memory CD8(+) T cells purified from wt mice that had been orally immunized cleared RV more efficiently than alpha(4)ss(7)(low) CD8(+) T cells. We explained this apparent contradiction by demonstrating that expression of alpha(4)ss(7) on effector CD8(+) T cells depends upon the site of initial antigen exposure: oral immunization generates RV-specific CD8(+) T cells primarily of an alpha(4)ss(7)(hi) phenotype, but subcutaneous immunization yields both alpha(4)ss(7)(hi) and alpha(4)ss(7)(low) immune CD8(+) T cells with anti-RV effector capabilities. Thus, alpha(4)ss(7) facilitates normal intestinal immune trafficking to the gut, but it is not required for effective CD8(+) T cell immunity.

[Micro determination of acrylonitrile in ambient air by gas chromatography]

Acrylonitrile in ambient air was collected by Tenax GC and then thermo-desorbed. It was separated on GDX-502 chromatographic column from other pollutants and determined by flame-ion ization detector. The minimum detectable concentration was 0.01 mg/m3 when 2 L ambient air was collected. The recoveries were 85.6%-105.4% and RSDs were 4.5%-6.2%.

Binding of interleukin-13 and interleukin-4 to the interleukin (IL)-4/IL-13 receptor of human synovial fibroblasts

Synovial fibroblasts expressed transcripts for IL-4R alpha, and IL-13R alpha 1 and IL-13R alpha 2. Using weighted nonlinear computer modeling of the data from equilibrium binding studies, a 2 bindings sites model fitted the data best. After occupation of the shared high affinity receptors by the non-signaling, double mutant IL-4(121)R-->D, 124Y-->D (RY-IL-4) the high affinity binding of IL-13 could be abolished. A 2 binding site model still could be fitted, however the improvement in fit over a onesite model was not statistically significant. Using affinity spectra, at least 2 binding sites are apparent. After treatment with RY-IL-4, some of the high affinity binding was abolished, however not completely. A correlation between the number of binding sites and the affinity is apparent, which seriously casts doubt on the classical evaluation of binding isotherms, where the parameters are assumed to be independent. In a previous study we suggested that the large number of IL-13R alpha 2 monomers are silent receptors, likely representing a decoy target for IL-13. The high affinity binding therefore most likely represents the binding to the heterodimer consisting of IL-4R alpha and IL-13R alpha 1 or IL-13R alpha 2. The low affinity binding may represent the IL-13R alpha 2.

The interleukin-4/interleukin-13 receptor of human synovial fibroblasts: overexpression of the nonsignaling interleukin-13 receptor alpha2

Interleukin (IL)-4 and IL-13 are known to bind to shared heteromultimeric receptor complexes of variable composition. Given the many regulatory effects of IL-4 and IL-13 on synovial cells, we aimed to characterize their IL-4/IL-13 receptor (R). Cultivated synovial fibroblasts expressed transcripts for IL-4Ralpha and IL-13Ralpha1, the human homolog of the recently cloned mouse IL-13R, but not the common gamma-chain of the IL-2R. In particular, IL-13Ralpha2 mRNA, encoding a different IL-13R recently cloned from human renal carcinoma cells, was expressed at a strikingly high level. Correspondingly, a predominant protein migrating at 65 to 75 kd was cross-linked by iodinated IL-13 and was not cross-competed by an excess of unlabeled IL-4. However, by flow cytofluorometry, IL-13Ralpha1 (detected by the anti-lL-13Ralpha1 mAb 65) and IL-4Ralpha (detected by the mAb S697) were expressed at similar low density. Radioligand binding studies revealed for both cytokines approximately 300 receptors/cell with similar high affinity. An additional class of IL-13Rs was identified after occupation of the shared high-affinity receptors by the nonsignaling, double-mutant IL-4121R-->D, 124Y-->D (RY-IL-4). In these experiments, 1251-IL-13 bound to a single receptor population with a Kd of approximately 300 pM and approximately 5000 sites/cell, matching the published affinity of monomeric IL-13Ralpha2 when expressed in COS7 cells. RY-IL-4 blocked the IL-4- and IL-13-mediated vascular cell adhesion molecule (VCAM)-1 expression and Stat6 activation, suggesting that the large number of high-affinity IL-13Ralpha2 monomers are silent receptors, likely representing a decoy target for IL-13.

Identification of mutations in the rotavirus protein VP4 that alter sialic-acid-dependent infection

To explore further the role of VP4 as the rotavirus cell attachment protein, VP7 monoreassortants derived from the sialic-acid-dependent simian strain RRV and from the sialic-acid-independent human strains D, DS-1 and ST-3 were tested for susceptibility of infectivity of neuraminidase-treated MA-104 cells. Infectivity of RRV x D VP7 and RRV x ST-3 VP7 monoreassortants decreased when sialic acid was removed from the cell surface. However, of three separate RRV x DS-1 VP7 monoreassortants tested, only one was sialic-acid-dependent. Sequence analysis showed that both sialic-acid-independent strains contained a single amino acid change, Lys to Arg, at position 187. In addition, sialic-acid-independent infectivity was seen in one of 14 RRV VP4 neutralization escape mutants tested, and this strain was found to have a Gly to Glu change at amino acid position 150. These results indicate that positions 150 and 187 of VP4 play an important role in early rotavirus-cell interactions.

[Association between levels of plasma lipid profile with apolipoprotein B gene polymorphism in 93 children]

OBJECTIVE

To study the relationship between levels of plasma lipid profile and variation of apolipoprotein (Apo) B gene.

METHODS

The relationship between frequency of polymorphism genotype of Apo B gene Xba I locus and levels of plasma lipid profile was studied in 93 children aged eight to eleven years.

RESULTS

The frequency of dominant X- allele (common allele) in Xba I locus was 0.967 in the children and that of uncommon X+ allele 0.033. Average levels of plasma total cholesterol (TC) and low density lipoprotein cholesterol (LDL-ch) in children with X- X+ genotype (4.59 and 2.98 mmol/L, respectively) were significantly higher than those with X-X- genotype (3.84 and 2.32 mmol/L, respectively). Levels of TC and/or LDL-ch in 4 of 6, cases of X-X+ genotype exceeded their the 90th percentile, indicating association between X+ allele and high plasma cholesterol level.

CONCLUSION

To certain extent, there is association between polymorphism of Xba I locus of Apo B gene and levels of plasma lipid profile in children, which may be a genetic marker for abnormal level of plasma lipid profile during childhood.

Studies of the role for NSP4 in the pathogenesis of homologous murine rotavirus diarrhea

A rotavirus (RV) nonstructural protein, NSP4, has recently been proposed to function as an enterotoxin in the pathogenesis of RV diarrhea. The role of NSP4 in the pathogenesis of RV diarrhea was examined by infecting cystic fibrosis transmembrane conductance regulator (CFTR) knockout mice with virulent murine RV and by comparing deduced amino acid sequences of RV gene 10 encoding NSP4 from three distinct sets of virulent and tissue culture-adapted avirulent variant RVs. Homozygous CFTR (CFTR-/-) mice, which do not respond to any known intestinal secretagogues, experienced diarrhea comparable to that in normal CFTR+/+ littermates after RV challenge. Comparison of amino acid sequences of NSP4 from virulent and attenuated pairs of RVs failed to show consistent or significant changes. Together, these data suggest that enterotoxigenic properties of RV NSP4 are not critical in the pathogenesis of murine RV diarrhea and that attenuation of murine RVs is not usually mediated by mutations in the gene encoding NSP4.

Investigation of the metabolism of 7-(4-chlorbenzyl)-7,8,13,13a-tetrahydroberberine chloride in the rat

The metabolism of 7-(4-chlorbenzyl)-7,8,13,13a-tetrahydroberberine chloride (CTHB), a compound with promising pharmacological effects against arrhythmia, was investigated in rat bile. A metabolite and unchanged CTHB were found in the bile. Characterization and structural elucidation of the metabolite was achieved by LC/MS and LC/NMR. The following metabolic pathway is proposed: CTHB is metabolized by demethylation at position 10 to produce a new entity.

Immune responses to individual rotavirus proteins following heterologous and homologous rotavirus infection in mice

Serum and intestinal humoral immune responses to rotavirus proteins VP2, VP4, VP6, VP7, NSP2, and NSP4 were quantitatively compared in mice infected with a homologous murine rotavirus (EHPw) or a heterologous simian rotavirus (RRV). Viral protein-specific antibody responses were measured by an immunohistochemistry assay that uses recombinant baculovirus-expressed rotavirus proteins as antigens. In serum, IgG responses to VP6 were dominant and comparable in both RRV- and EHPw-infected groups, but responses to VP2, VP4, VP7, and NSP2 were higher in RRV infection. In feces, IgA responses to VP2, VP4, and VP6 were higher in EHPw-infected mice, but responses to VP7 and NSP2 were detected only in the RRV-infected group. These findings indicate that immune responses to homologous and heterologous rotavirus infection vary both quantitatively and qualitatively. Differences in humoral responses may play a role in the differences in protection induced following homologous or heterologous rotavirus infection.

Tumor necrosis factor alpha enhances the expression of the interleukin (IL)-4 receptor alpha-chain on endothelial cells increasing IL-4 or IL-13-induced Stat6 activation

Functional receptors for interleukin (IL)-4 and IL-13 on endothelial cells consist of the 130-kDa IL-4 receptor alpha-chain (IL-4Ralpha) and a 65-75-kDa IL-13 binding subunit that are expressed in a ratio of about 1:3, respectively. The restricted number of IL-4Ralpha limits subunit heterodimerization and in turn receptor-mediated signaling. We report here, the effects of tumor necrosis factor alpha (TNF-alpha) on the expression of the receptor subunits for IL-4 and IL-13. By flow cytofluorometry and receptor-binding analysis of iodinated IL-4 and IL-13, stimulation with TNF-alpha-induced a 2-3-fold increase of the IL-4Ralpha expression. The up-regulation was also confirmed at the transcriptional level by reverse transcription-polymerase chain reaction. Radioligand cross-linking experiments revealed no change in the subunit composition of the TNF-alpha-induced receptor complex. Nevertheless, TNF-alpha stimulation led to increased activation of the IL-4-specific signal transducers and activators of transcription protein (Stat6) by IL-4 and IL-13. Thus, TNF-alpha corrects the subunit imbalance of the endothelial IL-4.IL-13 receptor complex thereby increasing receptor heterodimerization and in turn the signaling capability by IL-4 and IL-13.

Heterotypic protection following oral immunization with live heterologous rotaviruses in a mouse model

A Jennerian approach using live animal viruses to immunize humans is the current lead strategy for developing rotavirus vaccines. This strategy has been modified by incorporating human rotavirus VP7 genes into vaccine strains to induce serotype-specific neutralizing antibodies to human strains. However, the role of homotypic versus heterotypic immunity in protection is unclear. To investigate the importance of serotype-specific immunity in a mouse model, mice were immunized with rhesus rotavirus (RRV: G3, P5[3]), RRV-based modified Jennerian vaccine strains DxRRV (G1, P5[3]), DS1xRRV (G2, P5[3]), or ST3xRRV (G4, P5[3]), or bovine rotavirus NCDV (G6, P6[1]) and challenged with murine rotavirus ECw (G3, P[16]). Mice immunized with modified Jennerian vaccines exhibited complete to near-complete protection from challenge. NCDV-immunized mice also showed partial protection. The protection was correlated with fecal IgA levels to VP6, not serum IgG responses. Modified Jennerian vaccines induce both heterotypic and homotypic immunity in mice.