[A case of glufosinate-ammonium poisoning in a patient with total gastrectomy].

Objective: To analyze the diagnosis and treatment of a patient with glufosinate-ammonium poisoning after total gastrectomy. Methods: The clinical data of a patient with oral glufosinate-ammonium poisoning after total gastrectomy in the First Affiliated Hospital of Nanjing Medical University in August 2020 were analyzed. Results: After total gastrectomy, the patient took about 200 ml of glufosinate-ammonium orally, and the plasma glufosinate-ammonium concentration was 816.8 ng/ml 6.5 h after poisoning. After symptomatic treatment such as promoting poison excretion, rehydration, anti infection and protecting important organs, the patient improved and discharged. Conclusion: The clinical manifestations of patients with glufosinate-ammonium poisoning after total gastrectomy are still mainly neurological symptoms, with delayed effect. Whether total gastrectomy will affect the distribution and toxic effect of the poison still needs further exploration.

[Cloning and expression of recombinant truncated SElX protein and evaluation on the related emetic activities].

Objective: To analyze the amino acid polymorphism of truncated Staphylococcal enterotoxin-like toxin X (tSElX), and to evaluate its related emetic activities. Methods: Sequence of tselx was compared with both the genome sequence of 145 CC398 strains completed in our research group and the NCBI database. Primers were designed to amplify the target gene of tselx, and the fragment was recombined into pMD18-T vector and sequenced. PCR product was digested with BamHⅠ and EcoRⅠ, and constructed into plasmid pGEX-6P-1 and pET-28a (+). After recombinant plasmid was identified, the protein expression was induced by IPTG. Proteins expressed in the form of inclusion bodies were denatured and renatured, then purified by affinity chromatography and ultrafiltration. Purified tSElX protein was then fed to common marmosets with the dose of 250 µg/kg to observe the vomiting reaction. Results: tselx gene was present in 145 strains of CC398 strains from the different origins (patients, healthy people and animals) in China. Homology of the amino acid sequence of the protein from the Chinese strains appeared 100.0%, while the homology with the four American strains were 97.8%(1) and 98.9%(3), respectively. Through two sets of expression systems and different induction conditions, tSElX was expressed in the form of inclusion bodies. The high purity soluble recombinant tSElX was thus obtained by denaturated and renaturated processes. At the dose of 250 µg/kg, tSElX protein did not cause vomiting in common marmosets. Conclusions: Results of this study showed that the amino acid sequence of tSElX was highly conserved and was universally present in a particular clone group. We obtained soluble recombinant tSElX protein with high purity. We also noticed that tSElX did not have the animal emetic activity at a dose of 250 µg/kg.

[Analysis of reasons for failure of Meek micro-skin grafting in children with severe burn and treatment measures].

Objective: To analyze the reasons for failure of Meek micro-skin grafting in children with severe burns and to observe the clinical effects of the treatment measures. Methods: Thirty children with severe burns hospitalized in the First Affiliated Hospital of Anhui Medical University (hereinafter referred to as the author's affiliation) from January 2012 to January 2018, conforming to the inclusion criteria were included to failed skin graft group. Children in failed skin graft group were performed with Meek micro-skin grafting operation and the operation failed, including 17 males and 13 females aged 1 to 12 year(s). Thirty children with severe burns hospitalized in the author's affiliation during the same period of time, conforming to the inclusion criteria, were included to successful skin graft group. Children in successful skin graft group were performed with Meek micro-skin grafting operation and the operation succeeded, including 16 males and 14 females aged 1 to 12 year(s). Main treatment measures and effects before operation, area and survival rate of Meek micro-skin graft, infected pathogens status, selection status of sensitive antibiotics, preoperative nutrition status, and wound infection status in plum rain season of children in the two groups, and nutritional status before and after strengthening nutritional support of postoperative surviving children in failed skin graft group were analyzed retrospectively. Data were processed with chi-square test and t test. Results: (1) The numbers of children in the two groups performed with main treatment measures of dilatation and anti-shock, tracheotomy intubation, ventilator-assisted respiration, and limb incision decompression after admission were close (χ(2)=0, 0.016, 0.025, 0.009, P>0.05). After taking the above-mentioned main treatment measures, effects of correcting shock, preventing asphyxia, correcting breathing difficulty, and improving peripheral circulation of limb were achieved. (2) The area of Meek micro-skin grafting of children in successful skin graft group was (20.6±2.5)% total body surface area (TBSA), close to (21.2±2.2)% TBSA in failed skin graft group (t=0.534, P>0.05). The survival rate of Meek micro-skin graft of children in successful skin graft group was (79±5)%, significantly higher than (26±3)% in failed skin graft group (t=2.956, P<0.01). (3) The microbial culture of wound secretion of 5 (16.67%) children in 30 patients in successful skin graft group was positive, with Pseudomonas aeruginosa of 2 children, and Escherichia coli, Staphylococcus aureus, and Aspergillus of one patient respectively. As children in successful skin graft group were with no symptom of systemic infection, no blood microbial culture was done. The microbial culture of wound secretion of 30 (100.00%) children in 30 patients in failed skin graft group was positive, and blood microbial culture of 8 (26.67%) children was positive. The main pathogen was Pseudomonas aeruginosa of 11 (36.67%) children in 8 pathogens caused infection with gram-negative bacteria of 22 (73.33%), gram-positive bacteria of 11 (36.67%) children, and fungi of 6 (20.00%) children. (4) Ten kinds of sensitive antibiotics such as cephalosporins, glycopeptides, carbapenems, and tetracyclines antibiotics were used in children in failed skin graft group, of which the use rate of imipenem of 9 (30.00%) was the highest. Only 4 kinds of sensitive antibiotics such as ceftazidime were used in 30 children in successful skin graft group. (5) The preoperative levels of albumin and prealbumin of children in successful skin graft group were (32±4) g/L and (133±41) mg/L respectively, significantly higher than (27±4) g/L and (93±35) mg/L in failed skin graft group (t=5.090, 4.064, P<0.01). The albumin and prealbumin levels of postoperative surviving children in failed skin graft group after nutritional support treatment were (35±4) g/L and (168±49) mg/L, significantly higher than (27±4) g/L and (94±38) mg/L before nutritional support treatment (t=6.911, 6.315, P<0.01). (6) Wound infection of 9 children in 30 children with wound infection in failed skin graft group happened in the plum rain season, and fungi infection of 3 children in 6 children with fungi infection happened in the plum rain season. Wound infection of 2 children in 5 children with wound infection in successful skin graft group happened in the plum rain season, and the only one children with fungi infection happened in the plum rain season. Conclusions: The main reasons for the failure of Meek micro-skin grafting in children with severe burns include infection, nutrition, and season factors, etc. Measures of strengthening wound dressing change, reasonable use of sensitive antibiotics to control infection, internal and external intestinal nutritional support, and reducing disturbance of the plum rain season by enhancing ventilation are effective and worthy of clinical promotion.

[Regulation of hypoxia inducible factor-1α on permeability of vascular endothelial cells and the mechanism].

Objective: To investigate the regulation of hypoxia-inducible factor-1α (HIF-1α) on permeability of rat vascular endothelial cells and the mechanism. Methods: Twelve male Sprague-Dawley rats aged 35 to 38 days were collected and vascular endothelial cells were separated and cultured. The morphology of cells was observed after 4 days of culture, and the following experiments were performed on the 2nd or 3rd passage of cells. (1) Rat vascular endothelial cells were collected and divided into blank control group, negative control group, HIF-1α interference sequence 1 group, HIF-1α interference sequence 2 group, and HIF-1α interference sequence 3 group according to the random number table (the same grouping method below), with 3 wells in each group. Cells in negative control group, HIF-1α interference sequence 1 group, HIF-1α interference sequence 2 group, and HIF-1α interference sequence 3 group were transfected with GV248 empty plasmid, recombinant plasmid respectively containing HIF-1α interference sequence 1, interference sequence 2, and interference sequence 3 with liposome 2000. Cells in blank control group were only transfected with liposome 2000. After transfection of 24 h, expression levels of HIF-1α mRNA and protein of cells in each group were respectively detected by reverse transcription real-time fluorescent quantitative polymerase chain reaction and Western blotting (the same detecting methods below) . The sequence with the highest interference efficiency was selected. (2) Another batch of rat vascular endothelial cells were collected and divided into blank control group, negative control group, and HIF-1α low expression group, with 3 wells in each group. Cells in blank control group were only transfected with liposome 2000, and cells in negative control group and HIF-1α low expression group were respectively transfected with GV248 empty plasmid and low expression HIF-1α recombinant plasmid selected in experiment (1) with liposome 2000. After 14 days of culture, the mRNA and protein expressions of HIF-1α in each group were detected. (3) Another batch of rat vascular endothelial cells were collected and divided into blank control group, negative control group, and HIF-1α high expression group, with 3 wells in each group. Cells in blank control group were transfected with liposome 2000, and cells in negative control group and HIF-1α high expression group were respectively transfected with GV230 empty plasmid and HIF-1α high expression recombinant plasmid with liposome 2000. After 14 days of culture, the mRNA and protein expressions of HIF-1α of cells in each group were detected. (4) After transfection of 24 h, cells of three groups in experiment (1) and three groups in experiment (2) were collected, and mRNA and protein expressions of myosin light chain kinase (MLCK), phosphorylated myosin light chain (p-MLC), and zonula occludens 1 (ZO-1) of cells were detected. Data were processed with one-way analysis of variance and t test. Results: After 4 days of culture, the cells were spindle-shaped, and rat vascular endothelial cells were successfully cultured. (1) The interference efficiencies of HIF-1α of cells in HIF-1α interference sequence 1 group, HIF-1α interference sequence 2 group, and HIF-1α interference sequence 3 group were 47.66%, 45.79%, and 62.62%, respectively, and the interference sequence 3 group had the highest interference efficiency. After transfection of 24 h, the mRNA and protein expression levels of HIF-1α of cells in interference sequence 3 group were significantly lower than those in blank control group (t=18.404, 9.140, P<0.01) and negative control group (t=15.099, 7.096, P<0.01). (2) After cultured for 14 days, the mRNA and protein expression levels of HIF-1α of cells in HIF-1α low expression group were significantly lower than those in blank control group (t=21.140, 5.440, P<0.01) and negative control group (t= 14.310, 5.210, P<0.01). (3) After cultured for 14 days, the mRNA and protein expression levels of HIF-1α of cells in HIF-1α high expression group were significantly higher than those in blank control group (t=19.160, 7.710, P<0.01) and negative control group (t= 19.890, 7.500, P<0.01). (4) After transfection of 24 h, the mRNA expression levels of MLCK and p-MLC of cells in HIF-1α low expression group were significantly lower than those in blank control group (t=2.709, 4.011, P<0.05 or P<0.01) and negative control group (t=2.373, 3.744, P<0.05 or P<0.01). The mRNA expression level of ZO-1 of cells in HIF-1α low expression group was significantly higher than that in blank control group and negative control group (t=4.285, 5.050, P<0.01). The mRNA expression levels of MLCK and p-MLC of cells in HIF-1α high expression group were significantly higher than those in blank control group (t=9.118, 11.313, P<0.01) and negative control group (t=9.073, 11.280, P<0.01). The mRNA expression level of ZO-1 of cells in HIF-1α high expression group was significantly lower than that in blank control group and negative control group (t=2.889, 2.640, P<0.05). (5) After transfection of 24 h, the protein expression levels of MLCK and p-MLC of cells in HIF-1α low expression group were significantly lower than those in blank control group (t=2.652, 3.983, P<0.05 or P<0.01) and negative control group (t=2.792, 4.065, P<0.05 or P<0.01). The protein expression of ZO-1 of cells in HIF-1α low expression group was significantly higher than that in blank control group and negative control group (t=3.881, 3.570, P<0.01). The protein expression levels of MLCK and p-MLC of cells in HIF-1α high expression group were 1.18±0.24 and 0.68±0.22, which were significantly higher than 0.41±0.21 and 0.35±0.14 in blank control group (t=5.011, 3.982, P<0.05 or P<0.01) and 0.43±0.20 and 0.36±0.12 in negative control group (t= 4.880, 3.862, P<0.05 or P<0.01). The protein expression level of ZO-1 of cells in HIF-1α high expression group was 0.08±0.06, which was significantly lower than 0.20±0.09 in blank control group and 0.19±0.09 in negative control group (t=4.178, 3.830, P<0.05 or P<0.01). Conclusions: HIF-1α up-regulates expressions of MLCK and p-MLC and down-regulates expression of ZO-1, thereby increasing the permeability of rat vascular endothelial cells.

[Influence of three-level collaboration network of pediatric burns treatment in Anhui province on treatment effects of burn children].

Objective: To explore the influence of three-level collaboration network of pediatric burns in Anhui province on treatment effects of burn children. Methods: The data of medical records of pediatric burn children transferred from Lu'an People's Hospital and Fuyang People's Hospital to the First Affiliated Hospital of Anhui Medical University from January 2014 to December 2015 and January 2016 to September 2017 (before and after establishing three-level collaboration network of pediatric burns treatment) were analyzed: percentage of transferred burn children to hospitalized burn children in corresponding period, gender, age, burn degree, treatment method, treatment result, occurrence and treatment result of shock, and operative and non-operative treatment time and cost. Rehabilitation result of burn children transferred back to local hospitals in 2016 and 2017. Data were processed with t test, chi-square test, Mann-Whitney U test, and Fisher's exact test. Results: (1) Percentage of burn children transferred from January 2014 to December 2015 was 34.3% (291/848) of the total number of hospitalized burn children in the same period of time, which was close to 30.4% (210/691) of burn children transferred from January 2016 to September 2017 (χ(2)=2.672, P>0.05). (2) Gender, age, burn degree, and treatment method of burn children transferred from the two periods of time were close (χ(2)=3.382, Z=-1.917, -1.911, χ(2)=3.133, P>0.05). (3) Cure rates of children with mild, moderate, and severe burns transferred from January 2016 to September 2017 were significantly higher than those of burn children transferred from January 2014 to December 2015 (χ(2)=11.777, 6.948, 4.310, P<0.05). Cure rates of children with extremely severe burns transferred from the two periods of time were close (χ(2)=1.181, P>0.05). (4) Children with mild and moderate burns transferred from the two periods of time were with no shock. The incidence of shock of children with severe burns transferred from January 2014 to December 2015 was 6.0% (4/67), and 3 children among them were cured. The incidence of shock of children with severe burns transferred from January 2016 to September 2017 was 3.9% (2/51), and both children were cured. The incidences and cures of shock of children with severe burns transferred from the two periods of time were close (χ(2)=0.006, P>0.05). Incidence of shock of children with extremely severe burns transferred from January 2014 to December 2015 was 57.1% (32/56), significantly higher than that of burn children transferred from January 2016 to September 2017 [34.5% (10/29), χ(2)=3.925, P<0.05]. Shock of 25 children with extremely severe burns transferred from January 2014 to December 2015 were cured, and shock of 9 children with extremely severe burns transferred from January 2016 to September 2017 were cured. The cures of shock of children with extremely severe burns transferred from the two periods of time were close ( χ(2)=0.139, P>0.05). (5) Time of operative treatment of children with moderate, severe, and extremely severe burns transferred from January 2014 to December 2015 was obviously longer than that of burn children transferred from January 2016 to September 2017 (t=2.335, 2.065, 2.310, P<0.05). Time of operative treatment of children with mild burns transferred from the two periods of time was close (Z=-0.417, P>0.05). Costs of operative treatment of children with moderate and severe burns transferred from January 2014 to December 2015 were significantly more than those of burn children transferred from January 2016 to September 2017 (Z=-3.324, t=2.167, P<0.05). Costs of operative treatment of children with mild and extremely severe burns transferred from the two periods of time were close (t=0.627, 0.808, P>0.05). (6)Time of non-operative treatment of children with mild, moderate, and severe burns transferred from January 2014 to December 2015 was obviously longer than that of burn children transferred from January 2016 to September 2017 (t=2.335, Z=-2.095, t=2.152, P<0.05). Time of non-operative treatment of children with extremely severe burns transferred from the two periods of time was close (t=0.450, P>0.05). Costs of non-operative treatment of children with moderate and severe burns transferred from January 2014 to December 2015 were obviously higher than those of burn children transferred from January 2016 to September 2017 (Z=-2.164, t=2.040, P<0.05). Costs of non-operative treatment of children with mild and extremely severe burns transferred from the two periods of time were close (t=0.146, 1.235, P>0.05). (7) Sixty-seven burn children transferred from January 2016 to September 2017 were transferred back to local hospitals for rehabilitation under the guidance of experts of the First Affiliated Hospital of Anhui Medical University, with 25 patients in 2016 and 42 patients in 2017. Effective rehabilitation rates of burn children transferred back to local hospitals for rehabilitation in 2016 and 2017 were both 100%. Conclusions: The three-level collaboration network of pediatric burns treatment in Anhui province can effectively increase cure rate of children with mild, moderate, and severe burns, reduce incidence of shock of children with extremely severe burns, shorten time of operative treatment of burn children with moderate, severe, and extremely severe burns, and time of non-operative treatment of children with mild, moderate, and severe burns, reduce treatment costs of children with moderate and severe burns, and improve rehabilitation effectiveness of children transferred from Lu'an People's Hospital and Fuyang People's Hospital to the the First Affiliated Hospital of Anhui Medical University.

Biological characteristics of staphylococcal enterotoxin Q and its potential risk for food poisoning.

AIMS: To elucidate the biological characteristics and stability of a newly identified staphylococcal enterotoxin Q (SEQ) against heating and digestive enzymes and to evaluate the risk of seq-harbouring Staphylococcus aureus in food poisoning. METHODS AND RESULTS: Purified SEQ was treated with heating, pepsin and trypsin which are related to food cooking, stomach and intestine conditions, respectively. Superantigenic activity of SEQ was assessed by determining the ability of IL-2 induction in mouse spleen cells. The emetic activity of SEQ was assessed using house musk shrew, a small emetic animal model. The results revealed that SEQ exhibits a remarkable resistance to heat treatment and pepsin digestion and has significant superantigenic and emetic activities. Furthermore, a sandwich ELISA for detection of SEQ production was developed, and the results showed that seq-harboring S. aureus isolates produce a large amount of SEQ. CONCLUSIONS: The newly identified SEQ had remarkable stability to heat treatment and digestive enzyme degradation and exhibited significant superantigenic and emetic activities. In addition, seq-harbouring S. aureus isolated from food poisoning outbreaks produced a large amount of SEQ, suggesting that seq-harbouring S. aureus could potentially be a hazard for food safety. SIGNIFICANCE AND IMPACT OF THE STUDY: This study found, for the first time, that SEQ, a nonclassical SE, had remarkable stability to heat treatment and enzyme degradation and exhibited significant emetic activity, indicating that SEQ is a high-risk toxin in food poisoning.

Sodium tanshinone IIA sulfonate and its interactions with human CYP450s.

1.Sodium tanshinone IIA sulfonate (STS) is a water-soluble derivative of tanshinone IIA, a famous Chinese medicine used for many years to treat cardiovascular disorders. However, the role of cytochrome P450 (CYP) enzymes in the metabolism of STS was unclear. In this study, we screened the main CYPs for the metabolism of STS and studied their interactions in vitro. 2.Seven CYPs were screened for the metabolism of STS by human liver microsomes (HLMs) or recombinant CYP isoforms. To determine the potential of STS to affect CYP-mediated phase I metabolism in humans, phenacetin (CYP1A2), coumarin (CYP2A6), tolbutamide (CYP2C9), metoprolol (CYP2D6), chlorzoxazone (CYP2E1), S-Mephenytoin (CYP2C19), and midazolam (CYP3A4) were used as the respective probe substrates. Enzyme kinetic studies were performed to investigate the mode of inhibition of the enzyme-substrate interactions. 3.STS inhibited the activity of CYP3A4 in a dose-dependent manner in the HLMs and CYP3A4 isoform. Other CYP isoforms, including CYP1A2, CYP2A6, CYP2C9, CYP2D6, CYP2E1, and CYP2C19, showed minimal or no effect on the metabolism of STS. 4.The results suggested that STS primarily inhibits the activities of CYP3A4 in vitro, and STS has the potential to perpetrate drug-drug interactions with other CYP3A4 substrates.

Goblet cells are involved in translocation of staphylococcal enterotoxin A in the intestinal tissue of house musk shrew (Suncus murinus).

AIMS: To elucidate an entry site of staphylococcal enterotoxin A (SEA), which is a major toxin for staphylococcal foodborne poisoning, into gastrointestinal tissue using a house musk shrew model. METHODS AND RESULTS: House musk shrews were per orally administered with recombinant SEA and localization of SEA in gastrointestinal tissues was investigated by immunohistochemistry and immunoelectron microscopy 30 min after administration. SEA was detected in a subset of intestinal epithelial cells and lamina propria in the villi of jejunum and ileum. This observation was also found in gastrointestinal loops. Morphological characteristics of the SEA-immunopositive cells indicated that goblet cells are an entry site of SEA.SEA entered mucus-expelling goblet cells and the induction of mucus secretion by alyll isothiocyanate resulted in an intensive SEA signal. These results suggest that mucus secretion by goblet cells is important for the translocation of SEA. CONCLUSIONS: SEA can translocate across intestinal epithelia via mucus-expelling goblet cells. SIGNIFICANCE AND IMPACTS OF THE STUDY: An entry site of SEA during translocation across the gastrointestinal mucosal barrier was investigated. This study was the first to demonstrate the significance of goblet cells as an entry site of this bacterial toxin.

Vibrational resonance in the FitzHugh-Nagumo system with time-varying delay feedback.

In the present paper, the phenomenon of vibrational resonance in a time-varying delayed FitzHugh-Nagumo system that is driven by two-frequency periodic signals is reported. Via a numerical simulation, the periodic vibrational resonances are found to be induced by the time-varying delay feedback under the condition that the delayed feedback strength is small, and then along with the increase of the delayed feedback strength K within the slow period (i.e., the period of low-frequency signal), the single resonance turns into multiple resonances. However, if the delayed feedback strength K is big enough, the resonance no longer occurs. More interestingly, the multiple resonances can also turn into a single resonance in a cycle by modulating the amplitude F of high-frequency signal. Furthermore, both the resonance region and the resonance amplitude are found to be able to be controlled by the time-varying delay. Finally, it is found that the regular motion of the system can be enhanced by the time-varying delay feedback and then more regular motion will present if the resonance does not occur.

Fabp3 inhibits proliferation and promotes apoptosis of embryonic myocardial cells.

Fatty acid binding protein 3 (FABP3) is a member of a family of binding proteins. The protein is mainly expressed in cardiac and skeletal muscle cells, and it has been linked to fatty acid metabolism, trafficking, and signaling. Using suppression subtractive hybridization, we previously found that FABP3 is highly regulated in ventricular septal defect (VSD) patients and may play a significant role in the development of human VSD. We therefore aimed to identify the biological characteristics of the FABP3 gene in embryonic myocardial cells. On the basis of RT-PCR and western blotting analyses, we demonstrated that the expression levels of FABP3 mRNA and protein were up-regulated initially and then gradually decreased with P19 cell differentiation. MTT assays and cell cycle analysis showed that FABP3 inhibits P19 cell proliferation, and data from annexin V-FITC assays revealed that FABP3 can promote apoptosis of P19 cells. Further data from quantitative real-time RT-PCR revealed lower expression levels of cardiac muscle-specific molecular markers (cTnT, alpha-MHC, GATA4, and MEF2c) in FABP3-overexpressing cell lines than in the control cells during differentiation. Our results demonstrate that FABP3 may be involved in the differentiation of cardiac myocytes.

Superantigenic activity of toxic shock syndrome toxin-1 is resistant to heating and digestive enzymes.

AIMS: To elucidate the stability of superantigenic activity and pathogenesis of toxic shock syndrome toxin 1 (TSST-1) and staphylococcal enterotoxin A (SEA) against heating and digestive enzymes. METHODS AND RESULTS: Purified TSST-1 and SEA were treated with heating, pepsin and trypsin that are related to food cooking, stomach and intestine conditions. The integrity, superantigenic activity and toxicity of treated TSST-1 and SEA were analysed by Western blotting, spleen cell culture, cytokine assay and toxic shock models. Both TSST-1 and SEA showed strong resistance to heating, pepsin and trypsin digestion. Furthermore, the treated TSST-1 showed significant higher induction of interferon-γ and toxic shock compared with that of SEA. Pepsin- or trypsin-digested TSST-1 fragments still showed significant superantigenic and lethal shock toxicities. CONCLUSIONS: The superantigenic activity of TSST-1 was stable to heating and digestive enzymes. Pepsin- and trypsin-digested TSST-1 fragments still showed superantigenic and lethal shock activities, indicating that digested TSST-1 could cross epithelial cells and induce systemic toxicity. SIGNIFICANCE AND IMPACT OF THE STUDY: This study found, for the first time, that pepsin- or trypsin-digested smaller TSST-1 retained significant superantigenic and lethal shock activities. The different resistance of TSST-1 and SEA participates in the different pathogenic activities during food poisoning and toxic shock syndrome.

Inhibition of EGFR pathway signaling and the metastatic potential of breast cancer cells by PA-MSHA mediated by type 1 fimbriae via a mannose-dependent manner.

To identify more therapeutic targets and clarify the detailed mechanisms of Pseudomonas aeruginosa-mannose-sensitive hemagglutinin (PA-MSHA) on breast cancer cells both in vitro and in vivo. PA-MSHA was administered to epidermal growth factor receptor (EGFR)-positive human breast cancer cell lines MDA-MB-231HM and MDA-MB-468 in vitro and to mice bearing tumor xenografts. The mannose cocultured test was used to detect the effect of mannose on PA-MSHA-induced cell proliferation, cell cycle arrest, apoptosis, and EGFR pathway signaling. We found that cells stimulated with PA-MSHA exhibited a downregulation of EGFR signaling. The addition of mannose partially inhibited the PA-MSHA-stimulated cell anti-proliferative effect, cell apoptosis, cell cycle arrest, activation of apoptosis-associated caspases, and even downregulation of the EGFR signaling pathway. In vivo, PA-MSHA treatment significantly suppressed mammary tumorigenesis in xenografts in mice and decreased lung metastasis in MDA-MB-231HM cell-transplanted mice. Tumor sample analyses confirmed inhibition of the EGFR pathway in the PA-MSHA-treated mice. In conclusion, this study showed that the involvement of the mannose-mediated EGFR pathway has a critical function in the preclinical rationale for the development of PA-MSHA for the treatment of human breast cancer. It also suggests the potentially beneficial use of PA-MSHA in adjuvant therapy for breast tumors with EGFR overexpression.

Effect of glycyrrhizin on CYP2C19 and CYP3A4 activity in healthy volunteers with different CYP2C19 genotypes.

The objective of this study was to investigate the interaction between glycyrrhizin and omeprazole and observe the effects of glycyrrhizin on CYP2C19 and CYP3A4 activities in healthy Chinese male volunteers with different CYP2C19 genotypes. Eighteen healthy subjects (six CYP2C19*1/*1, five CYP2C19*1/*2, one CYP2C19*1/*3, five CYP2C19*2/*2 and one CYP2C19*2/*3) were enrolled in a two-phase randomized crossover trial. In each phase, all subjects received placebo or glycyrrhizin salt tablet 150 mg twice daily for 14 consecutive days. The pharmacokinetics of omeprazole (20 mg orally on day 15) was determined for up to 12 h following administration by high-performance liquid chromatography. After 14-day treatment of glycyrrhizin, plasma omeprazole significantly decreased, and those of omeprazole sulfone significantly increased. However, plasma concenetrations of 5-hydroxyomeprazole did not significantly change. The ratio of AUC(0-infinity) of omeprazole to omeprazole sulfone decreased by 43.93% + or - 13.56% (p = 0.009) in CYP2C19*1/*1, 44.85% + or - 14.84% (p = 0.002) in CYP2C19*1/*2 or *3 and 36.16% + or - 7.52% (p < 0.001) in CYP2C19*2/*2 or *3 while those of omeprazole to 5-hydroxyomeprazole did not change significantly in all three genotypes. No significant differences in glycyrrhizin response were found among CYP2C19 genotypes. Glycyrrhizin induces CYP3A4-catalyzed sulfoxidation of omeprazole and leads to decreased omeprazole plasma concentrations, but has no significant impact on CYP2C19-dependent hydroxylation of omeprazole.

Effects of the CYP2C9*13 allele on the pharmacokinetics of losartan in healthy male subjects.

The aim of the study was to determine the pharmacokinetics of losartan in relation to the CYP2C9*13 allele. A single oral dose of 50 mg losartan was administrated to each of the 16 healthy male volunteers with a different genotype (CYP2C9*1/*1, n = 6; CYP2C9*1/*13, n = 4; and CYP2C9*1/*3, n = 6). Blood samples were collected from pre-dose up to 24 h after the drug administration. Plasma losartan and E3174 (an active metabolite of losartan) were assayed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). All the subjects finished the study without adverse drug effects. In the present study, the frequencies of CYP2C9*13 and *13 alleles were 0.6% and 2.6% in Chinese healthy volunteers, respectively, and both alleles were in Hardy-Weinberg equilibrium. Compared with the subjects in the CYP2C9*1/*1 group, individuals carrying the CYP2C9*1/*13 genotype showed significantly a longer t(1/2) of losartan and E3174 and markedly increased the area under the curve (AUC) of losartan. Meanwhile, the CYP2C9*1/*3 genotype group had significant differences in t(1/2) and Cmax of E3174 compared with the CYP2C9*1/*1 group. The ratio of AUC(E3174)/AUC(losartan) after losartan administration in the CYP2C9*1/*13 and CYP2C9*1/*3 groups was also statistically different from that in the CYP2C9*1/*1 group. The data indicate that the presence of the CYP2C9*13 allele results in poor metabolism of losartan after a single oral dose.

Clopidogrel inhibits CYP2C19-dependent hydroxylation of omeprazole related to CYP2C19 genetic polymorphisms.

This study explores the impact of clopidogrel on the pharmacokinetics of omeprazole related to CYP2C19 genetic polymorphisms. Twelve healthy volunteers (6 CYP2C19*1/*1, 5 CYP2C19*2/*2, and 1 CYP2C19*2/*3) are enrolled in a 2-phase randomized crossover trial. In each phase, the volunteers are administered a single oral dose of omeprazole 40 mg after pretreatment of either placebo or clopidogrel (300 mg on the first day and then 75 mg once daily for 3 consecutive days). Plasma concentrations of omeprazole and its metabolites are quantified by high-performance liquid chromatography with UV detection. After clopidogrel treatment, the AUC(0-infinity) of omeprazole increases by 30.02% +/- 18.03% (P = .004) and that of 5-hydroxyomeprazole decreases by 24.30% +/- 11.66% (P = .032) in CYP2C19*1/*1. The AUC(0-infinity) ratios of omeprazole to 5-hydroxyomeprazole increase by 74.98% +/- 35.48% (P = .001) and those of omeprazole to omeprazole sulfone do not change significantly (P = .832) in CYP2C19*1/*1. No significant alteration is observed in CYP2C19*2/*2 or *3. Clopidogrel inhibits CYP2C19-dependent hydroxylation of omeprazole in CYP2C19*1/*1 and has no impact on CYP3A4-catalyzed sulfoxidation of omeprazole.

Effect of Schisandra chinensis extract and Ginkgo biloba extract on the pharmacokinetics of talinolol in healthy volunteers.

The authors investigated the effect of herbal medicine Schisandra chinensis extract (SchE) and Ginkgo biloba extract (GBE) on the oral pharmacokinetics of P-glycoprotein substrate talinolol in humans. Twelve healthy male volunteers took a single 100-mg oral dose of talinolol either alone or after pretreatment with 300 mg SchE twice daily or with 120 mg GBE three times daily for 14 days. On day 14, a single 100-mg oral dose of talinolol was administered. Plasma concentrations of talinolol from zero to 24 h were measured by high-performance liquid chromatography. SchE increased the area under the curve (AUC)(0-24) of talinolol by 47% (90% confidence interval (CI), 18-84%; p = 0.010), and GBE by 21% (90% CI = 11-32%; p = 0.002). The C(max) of talinolol increased by 51% (90% CI = 21-89%; p = 0.007) with SchE treatment and by 33% (90% CI = 18-51%; p = 0.002) with GBE treatment, respectively. The t(1/2) of talinolol increased by 7% (90% CI = -4% to 19%; p = 0.320) with SchE treatment and by 11% (90% CI = -12% to 38%; p = 0.436) with GBE treatment, respectively. The results suggest that both SchE and GBE significantly inhibited P-glycoprotein in humans. Patients receiving either SchE or GBE may require dose adjustments when treated with drugs primarily transported by P-glycoprotein.

The effect of herbal medicine baicalin on pharmacokinetics of rosuvastatin, substrate of organic anion-transporting polypeptide 1B1.

The aim of this study was to explore potential herb-drug interaction between baicalin and rosuvastatin, a typical substrate for organic anion-transporting polypeptide 1B1 (OATP1B1) related to different OATP1B1 haplotype groups. Eighteen unrelated healthy volunteers who were CYP2C9*1/*1 with different OATP1B1 haplotypes (six OATP1B1*1b/*1b, six OATP1B1*1b/*15, and six OATP1B1*15/*15) were selected to participate in this study. Rosuvastatin (20 mg orally) pharmacokinetics after coadministration of placebo and 50-mg baicalin tablets (three times daily orally for 14 days) were measured for up to 72 h by liquid chromatography-mass spectrometry in a two-phase randomized crossover study. After baicalin treatment, the area under the plasma concentration-time curve (AUC)(0-72) and AUC(0-infinity) of rosuvastatin decreased by 47.0+/-11.0% (P=0.001) and 41.9+/-7.19% (P=0.001) in OATP1B1*1b/*1b, 21.0+/-20.6% (P=0.035) and 23.9+/-8.66% (P=0.004) in OATP1B1*1b/*15, and 9.20+/-11.6% (P=0.077) and 1.76+/-4.89% (P=0.36) in OATP1B1*15/*15, respectively. Moreover, decreases of both AUC(0-72) and AUC(0-infinity) of rosuvastatin among different haplotype groups were significantly different (P=0.002 and <0.001). Baicalin reduces plasma concentrations of rosuvastatin in an OATP1B1 haplotype-dependent manner.

Analysis of the epitopes on staphylococcal enterotoxin A responsible for emetic activity.

To identify which region of staphylococcal enterotoxin A (SEA) is responsible for the emetic activity, twelve synthetic peptides corresponding to the entire SEA amino acid sequence and their respective anti-peptide antibodies were prepared and tested. The anti-peptide antibodies were tested for neutralization of SEA-induced emesis in Suncus murinus (Shrew mouse). The results indicate that SEA-induced emesis was neutralized by the mixture of three anti-peptide antibodies to A-7 (corresponding to amino acid residues 121-140), A-8 (141-160) and A-9 (160-180). These findings suggest that the regions corresponding to residues 121-180 may be the epitopes responsible for the emetic activity of SEA.

Emesis in the shrew mouse (Suncus murinus) induced by peroral and intraperitoneal administration of staphylococcal enterotoxin A.

Peroral and intraperitoneal administration of staphylococcal enterotoxin A (SEA) to Suncus murinus elicited an emetic response. The 50% emetic dose of SEA by peroral administration was found to be 32 microg per kg of body weight, whereas that by intraperitoneal administration was 3 microg per kg. Multiple emetic responses occurred 70 to 108 min after peroral administration of an emetic dose of SEA. Similar responses occurred 65 to 102 min after intraperitoneal injection of an emetic dose of SEA. No significant difference in vomiting was observed between male and female animals. Anti-SEA serum neutralized SEA-induced emesis in S. murinus. These findings indicate that S. murinus may serve as a suitable animal model to study the enterotoxigenicity of SEA.

Studies on the functional site on staphylococcal enterotoxin A responsible for production of murine gamma interferon.

To identify the functional region(s) associated with induction of gamma interferon on the staphylococcal enterotoxin A molecule, native staphylococcal enterotoxin A molecules and 12 various synthetic peptides corresponding to different regions of entire staphylococcal enterotoxin A were compared to induce gamma interferon production in murine spleen cells. The native staphylococcal enterotoxin A molecule induced gamma interferon production, whereas all of the 12 synthetic peptides did not. Pre-treatment of the murine spleen cells with synthetic peptide A-9 (corresponding to amino acid residues 161-180) significantly inhibited the staphylococcal enterotoxin A-induced gamma interferon production, whereas those with other synthetic peptides did not. When native staphylococcal enterotoxin A was pre-treated with either anti-staphylococcal enterotoxin A serum or anti-peptide sera, anti-staphylococcal enterotoxin A serum and antisera to peptides A-1 (1-20), A-7 (121-140), A-8 (141-160), A-9 (161-180) and A-10 (181-200) inhibited the staphylococcal enterotoxin A-induced gamma interferon production. From these findings, the amino acid residues 161-180 on the staphylococcal enterotoxin A molecule may be an essential region for murine gamma interferon production. Furthermore, the neutralizing epitopes may be also located on regions of amino acid residues 1-20, 121-140, 141-160 and 181-200 on the staphylococcal enterotoxin A molecule.