[Peripheral sterile corneal infiltrates after small incision lenticule extraction]

A 31-year-old female patient with refractive error in both eyes underwent small incision lenticule extraction. On the 4th day after surgery, arc-shaped peripheral corneal infiltrates appeared in the right eye. Tobramycin and dexamethasone eye drops, 0.3% gatifloxacin eye drops, and a corneal bandage lens were applied to the eye. After bacterial infection was ruled out, dexamethasone sodium phosphate was injected subconjunctivally near the corneal lesion. The symptoms improved and the corneal lesion subsided afterwards.

[Molecular epidemiological characterization of hypervirulent carbapenem-resistant Klebsiella pneumoniae in a hospital in Henan Province from 2020 to 2022]

Objective: The study investigated the clinical distribution, antimicrobial resistance and epidemiologic characteristics of hypervirulent Carbapenem-resistant Klebsiella pneumoniae (hv-CRKP) in a hospital in Henan Province to provide a scientific basis for antibiotic use and nosocomial infection prevention and control. Methods: A retrospective analysis of the clinical data from the cases was carried out in this study. Clinical data of patients infected with the CRKP strain isolated from the clinical microbiology laboratory of Henan Provincial Hospital of Traditional Chinese Medicine from January 2020 to December 2022 were retrospectively analyzed. A string test, virulence gene screening, serum killing, and a G. mellonella infection model were used to screen hv-CRKP isolates. The clinical characteristics of hv-CRKP and the drug resistance rate of hv-CRKP to twenty-five antibiotics were analyzed using WHONET 5.6. Carbapenemase phenotypic characterization of the hv-CRKP was performed by colloidal gold immunochromatographic assay, and Carbapenemase genotyping, multi-locus sequence typing (MLST) and capsular serotyping of hv-CRKP isolates were performed by PCR and Sanger sequencing. Results: A total of non-duplicate 264 CRKP clinical isolates were detected in the hospital from 2020 to 2022, and 23 hv-CRKP isolates were detected, so the corresponding detection rate of hv-CRKP was 8.71% (23/264). The hv-CRKP isolates in this study were mainly from the intensive care unit (10/23) and neurosurgery department (8/23), and the main sources of hv-CRKP isolates were sputum (10/23) and bronchoalveolar lavage fluid (6/23). The hv-CRKP isolates in this study were highly resistant to β-lactam antibiotics, fluoroquinolones and aminoglycosides, and were only susceptible to colistin, tigecycline and ceftazidime/avibactam. The detection rate of the blaKPC-2 among 23 hv-CRKP isolates was 91.30% (21/23) and none of the class B and class D carbapenemases were detected. Results of MLST and capsular serotypes showed that ST11 type hv-CRKP was the dominant strain in the hospital, accounting for 56.52% (13/23), and K64 (9/13) and KL47 (4/13) were the major capsular serotypes. Conclusion: The hv-CRKP isolates from the hospital are mainly from lower respiratory tract specimens from patients admitted to the intensive care department and the drug resistance is relatively severe. The predominant strains with certain polymorphisms are mainly composed of the KPC-2-producing ST11-K64 and ST11-KL47 hv-CRKP isolates in the hospital.

[Constructions and advances of animal models of Pseudomonas aeruginosa infection]

Pseudomonas aeruginosa (P. aeruginosa) is an opportunistic pathogenic bacterium with complex pathogenesis and drug resistance mechanisms. It has high morbidity and mortality and can cause acute and chronic infections in immunocompromised individuals, with lung infections, wound infections, and bloodstream infections being the most common. The animal infection model of P. aeruginosa is of great value for in-depth research on the pathogenicity, drug resistance, and therapeutic measures of P. aeruginosa by simulating the pathways of human bacterial infections. This article firstly summarizes the selection, anesthesia, and disposal of experimental animals in the construction of animal models of P. aeruginosa infection, and then reviews the methods of construction, model evaluation, and applications of animal models of P. aeruginosa pulmonary infection, wound infection, and bloodstream infection, in order to provide a reference for scientific research related to P. aeruginosa infectious diseases.

[Research advances of adipose stem cell matrix gel in promoting wound healing]

In recent years, with the problem of aging population in China being prominant, the number of patients with chronic wounds such as diabetic foot, pressure ulcer, and vascular ulcer is increasing. Those diseases seriously affect the life quality of patients and increase the economy and care burden of the patients' family, which have been one of the most urgent clinical problems. Many researches have confirmed that adipose stem cells can effectively promote wound healing, while exogenous protease is needed, and there are ethical and many other problems, which limit the clinical application of adipose stem cells. Adipose stem cell matrix gel is a gel-like mixture of biologically active extracellular matrix and stromal vascular fragment obtained from adipose tissue by the principle of fluid whirlpool and flocculation precipitation. It contains rich adipose stem cells, hematopoietic stem cells, endothelial progenitor cells, and macrophages, etc. The preparation method of adipose stem cell matrix gel is simple and the preparation time is short, which is convenient for clinical application. Many studies at home and abroad showed that adipose stem cell matrix gel can effectively promote wound healing by regulating inflammatory reaction, promoting microvascular reconstruction and collagen synthesis. Therefore, this paper summarized the preparation of adipose stem cell matrix gel, the mechanism and problems of the matrix gel in promoting wound repair, in order to provide new methods and ideas for the treatment of chronic refractory wounds in clinic.

[Current status and research advances on the use of assisted traction technique in endoscopic full-thickness resection]

Endoscopic full-thickness resection (EFTR) allows completely resecting deep submucosal tumors (SMTs) in the gastrointestinal wall, which has a broad application prospect in clinic. However, its application and promotion are limited by complex surgical procedures and high surgical risk. Various auxiliary traction techniques are expected to reduce the operation difficulty and risk of EFTR and improve its operative success rate. To provide a reference for clinicians, we summarize various auxiliary traction techniques in EFTR in this article. The clip-with-line method is simple to operate and widely used, whereas its traction is limited and there is a risk of clip falling off. The snare traction method and the clip-snare traction method has advantage of large traction force, but its thrust is affected by the hardness of snare. The traction point of the grasping forceps traction method is flexible and easy to adjust. Nevertheless, it requires the use of a dual-channel upper endoscope, which is difficult to operate. The transparent cap traction method and the full-thickness resection device traction method takes a short time and is easy to promote, whereas the resectable lesion is limited, and the size of the lesion may affect the success rate. In contrast, the suture loop needle-T-tag tissue anchors assisted method has a large resection range, but the operation is complicated and the feasibility has not been verified. The robot-assisted method has flexible operation and excellent visualization, whereas it is expensive and difficult to operate. There is no report of the application of magnetic anchor technology in EFTR, but it may have good application prospects in the auxiliary traction of EFTR.

[Research progress on virulence factors of hypervirulent Klebsiella pneumoniae]

Hypervirulent Klebsiella pneumoniae, short for hvKP, is a hypervirulent variant of classical Klebsiella pneumoniae, which accounts for serious infection in healthy people, exhibits strong pathogenicity, high mortality and poor prognosis. At present, hvkp is of high prevalence all over the world, and the infection rate shows a continuous upward trend, which brings great challenges to public health security and clinical treatment. This paper summarized the research progress on virulence factors of hvkp, such as capsular polysaccharides, siderophore, lipopolysaccharide, adhesins and recently discovered Type Ⅵ secreting system, and aimed to deepen the understanding and recognition of hvKP.

Efficacy and safety of lubiprostone for the treatment of functional constipation in Chinese adult patients: A multicenter, randomized, double-blind, placebo-controlled trial

OBJECTIVES

Functional constipation is a gastrointestinal disorder prevalent around the world. Lubiprostone is the first locally acting type-2 chloride channel activator to be used for treating constipation. This study aimed to evaluate the efficacy and safety of lubiprostone in Chinese adults with functional constipation.

METHODS

This was a multicenter, randomized, double-blind, placebo-controlled study. Patients with functional constipation were randomized to receive either lubiprostone (24 mcg twice daily) or placebo for 4 weeks. The primary end-point was the frequency of spontaneous bowel movements (SBMs) during the first week of treatment. The secondary end-points included the median time of the first SBM, SBM frequency at weeks 2, 3 and 4, weekly response rate of SBMs, the stool consistency score and average number of complete spontaneous bowel movements (CSBMs) per week.

RESULTS

In total, 259 patients were randomized, with 130 in the lubiprostone group and 129 in the placebo group. SBM frequency was higher in the lubiprostone group (4.88 ± 4.09/wk) than that in the placebo group (3.22 ± 2.01/wk) at week 1 (P < 0.0001). SBM frequency was also higher in the lubiprostone group at weeks 2, 3 and 4. The average number of CSBMs and the stool consistency score in the lubiprostone group were significantly higher than that in the placebo group at each week. No drug-related serious adverse events (AEs) occurred. The most commonly reported AE was nausea.

CONCLUSION

Lubiprostone was superior to placebo in treating Chinese patients with functional constipation, together with good safety profile.

[Predictive value analysis of Down's screening serological indicators in the second trimester for gestational hypertension]

Objective: To discuss the prediction efficacy of Down's screening serological indicators in the second trimester of gestational hypertension (GH). Methods: 64 849 pregnant women who had undergone regular check-ups at the Beijing Obstetrics and Gynecology Hospital from June 2013 to June 2019 and finally gave birth were the subjects of the study. There were 3 808 cases of the GH group (including patients with GH, preeclampsia, and eclampsia diagnosed) and 61 041 cases of non-GH group respectively. 3 ml of fasting venous blood was drawn during 14-19 weeks of pregnancy, and body weight, serum β-human chorionic gonadotropin (β-HCG), free estriol (uE3) and alpha fetal protein (AFP) were obtained through physical check and laboratory testing. β-HCG, AFP, uE3 were analyzed by using the corresponding median times of gestational age (MOM value), and multivariate logistic regression model and receiver operating characteristic curve (ROC curve) were used to analyze the predictive efficiency of serological indicators. Results: Among 64 849 research subjects, the GH group (3 808 cases) and the non-GH group (61 041) were (29.51±2.72), (29.38±2.68) years old, the weights were (65.46±12.17), (58.73±9.13) kg, gestational age of blood collection were (16.53±0.89) and (16.58±0.90) weeks respectively. The analysis of multivariate logistic regression model showed that the risk of GH increased with the increase of body weight, β-HCG and AFP concentration, OR (95%CI) values were 1.059 (1.056-1.062), 1.329 (1.188-1.487) and 1.195 (1.125-1.269); so did when the concentration of uE3 decrease, OR (95%CI) value was 0.527 (0.464-0.599). ROC curve analysis results show that age, weight, serum AFP, β-HCG, uE3 and multivariate diagnosis all have predictive efficiency for GH (P values<0.05); combined diagnosis of multiple indicators and weight AUC (95%CI) were 0.684 (0.675-0.693) and 0.673 (0.663-0.682), but the Youden index, sensitivity, and specificity of the two were relatively small. Conclusion: The β-HCG, AFP and uE3 of Down's screening in the second trimester of pregnancy were relatively low in predicting GH.

[Research progress on the regulation mechanism of Pseudomonas aeruginosa biofilm]

Pseudomonas aeruginosa is one of the common multidrug-resistant bacteria in the clinic. Because it can produce a "protective" biofilm, it can affect the penetration and killing efficacy of antibacterial drugs, leading to the formation of a persistent and persistent chronic infection in the host. Biofilms make Pseudomonas aeruginosa resistant to antibacterials and evasive to the host's immune system. Therefore, traditional conventional antibacterials are difficult to achieve effective bactericidal treatment. Understanding the process of P. aeruginosa biofilm formation and the regulatory mechanisms that affect biofilms can provide ideas and methods for our future research on new antibacterial drugs.

[Molecular epidemiological characteristics of methicillin-resistant Staphylococcus aureus during 2017-2018 at a hospital in Shanghai]

Objective: To identify the epidemic clones of MRSA isolates at a hospital in shanghai. Methods: A total of 72 MRSA isolates have been isolated from a second grade hospital between 2017 and 2018, including 32 CA-MRSA isolates, 13 HA-MRSA isolates and 26 MRSA isolates from environment. In this study, MLST and PFGE typing methods were used to analyze the molecular epidemiology of the MRSA isolates. Results: A total of 72 MRSA isolates have been obtained including 46 isolates from clinical specimens, 26 isolates from environments. The 46 MRSA isolates from clinical specimens consisted of 33 CA-MRSA (community-acquired MRSA) and 13 HA-MRSA (hospital-acquired MRSA). Furthermore, these patients infected with MRSA isolates were mostly distributed in the department of geriatrics (34.8%, 16/46), internal medicine (26.1%, 12/46) and surgery (26.1%, 12/46). MLST typing results showed that ST764 was predominant in isolates from both clinical specimens and hospital environments. Furthermore, PFGE typing results showed that most ST764 MRSA had high homolog (>90%). Conclusion: ST764 MRSA isolates might spread in community, hospital and environments. Therefore, continuous monitoring of MRSA and its variation may be useful in understanding the involvement of epidemic clone, and in searching new strategies to control MRSA infection.

[Multi-center empirical study of virtual gastroscopy simulator in the examination of clinical practice skills of specialist physicians]

Objective: To study the role of virtual gastroscopy simulator in the examination of clinical practice skills of gastrointestinal specialists. Methods: A multi-center empirical study was carried out. In June 2018, ninety participants from three tertiary care teaching hospitals in China, including Zhongshan Hospital of Fudan University, Shanghai Tongji Hospital and Xiangya Hospital of Central South University, took part in the examination. Participants were selected as follows: 30 specialists without any experience of gastroscopy exams, 30 with basic knowledge (gastroscopy exams <500 cases) and 30 with good skill (gastroscopy exams ≥500 cases). These 90 students participated in this empirical study after theoretical study and simulator training. Among them, 50 (55.6%) were undergraduates, 25 (27.8%) masters, and 15 (16.7%) doctors; 42 (46.7%) were residents, 39 (43.3%) attending physicians, and 9 (10.0%) deputy chief physicians. The assessment was divided into two parts. The first part was to use the simulator (GI mentor II) for ballooning within 10 minutes, with a total score of 40 points. The second part was a complete gastroscopy exam on the simulator, including preparation before gastroscopy exam, gastroscopy exam, post - exam management and related knowledge quiz. The difficulty and discrimination of the assessment plan were evaluated by the extreme grouping method parameters (difficulty P definition: <0.3 was difficult, 0.3 to 0.7 was medium, ≥0.7 was easy; discrimination degree D definition: <0 was poor, 0 to 0.2 was medium, ≥0.2 was good), and by comparing the virtual gastroscopy assessment scores of different experience, academic, and professional title groups. The score analysis of the student group was expressed using the mastering rate (the average score divided by the total score). The data of the normal distribution was represented by (mean±SD) (range), and the data of the nonnormal distribution was represented by M (P25, P75). Kruskal-Wallis non-parametric test was used for comparison between groups. Results: The total score of 90 students was (82.9±10.9) (55.8 to 99.0), and the mastering rate was 82.9%. The overall difficulty of the first and the second parts were 0.78 and 0.76, respectively, and the difficulty level was easy. The overall discrimination of the first and the second parts were 0.70 and 0.67, respectively, and the discrimination was good. The stratified analysis was performed according to the professional title. The median score was 83.2 (75.5, 89.0) in the residents, 82.5 (71.7, 93.6) in the attending physicians, and 93.5 (88.5, 99.0) in the deputy chief physicians, and the difference was statistically significant (H=6.213, P=0.045). According to the stratification analysis of academic qualifications, the median score was 81.7 (73.0, 87.5) in participants with undergraduate degree, 91.0 (79.0, 95.0) in those with master degree and 88.0 (81.7, 93.5) in those with doctor degree, whose difference was statistically significant (H=9.233, P=0.010). The stratified analysis of the second part showed that the median scores of the "operational process" part of the low, medium and high basis group were 33.0 (30.5, 36.5), 34.0 (32.0, 36.0) and 37.0 (35.0, 37.5), respectively, whose difference was statistically significant (H=7.603, P=0.022). The median scores of the "operational process" section of the resident, attending physician, and deputy chief physician were 33.0 (30.5, 35.0) points, 36.0 (34.0, 37.5) points and 37.0 (37.0, 37.5) points, respectively, whose difference was statistically significant (H=18.563, P=0.001). Conclusions: The virtual gastroscopy simulator can reflect the true level of gastroscopy exam skills of the students. The examination questions are moderately difficult, and there is a good discrimination of the exam.

[Application of Overlap anastomosis to Billroth I digestive tract reconstruction after laparoscopic distal gastrectomy in gastric cancer]

Objective: To investigate the application value of Overlap anastomosis in Billroth I digestive tract reconstruction after laparoscopic distal gastrectomy in gastric cancer. Methods: Clinical data of 68 stage T1-2 gastric cancer patients undergoing laparoscopic distal gastrectomy for D2 radical gastrectomy from January 2015 to January 2016 at China Japan Union Hospital of Jilin University were retrospectively analyzed. Inclusion criteria: (1) no distant metastasis of gastric cancer confirmed by gastroscopy and pathology before surgery; (2) T1-2 tumor with diameter <3 cm; (3) the lesion locating in the antrum of the stomach with distance >1 cm from the pylorus, and no invasion into middle area; (4) R0 resection confirmed by postoperative pathology; (5) no history of abdominal surgery. Among 68 cases,23 cases were in Overlap anastomosis group and 45 cases in Billroth I anastomosis group. D2 lymph node dissection and distal gastrectomy were performed in both groups. In the Overlap anastomosis group, the duodenum and stomach were severed by a linear stapler under endoscopy, and the residual gastric curve anastomotic opening was selected. According to the tension between the duodenum and the remnant stomach, the anastomotic opening was selected at the upper edge of the remnant duodenum, and the anastomosis between the posterior wall of the remnant stomach and the upper wall of the duodenum was completed by placing the stapler under endoscopy. Then the common opening was closed and the remnant duodenum was resected. In the traditional Billroth I anastomosis group, pneumoperitoneum was discontinued after amputation of the duodenum under laparoscopy. The median incision of the upper abdomen was 9-12 cm. The distal stomach was pulled out to complete the excision of specimens, the extraction of specimens and Billroth I digestive tract reconstruction. The intraoperative and postoperative conditions of the two groups were compared with student t test (continuous variable) and chi-square test (categorica variable). Results: Of the 68 patients,39 were males and 29 were females,with age of (65.5±10.2)(51 to 77)years. Differences in baseline data between Overlap group and Billroth I group were not statistically significant (all P>0.05). Laparoscopic surgery was successfully performed in both groups without conversion to open operation. As compared with the Billroth I group, the Overlap group had significantly shorter operation time [(149.8±10.1) minutes vs. (169.8±15.3) minutes, t=5.658,P=0.008], shorter anastomotic time of digestive tract reconstruction [(31.2±3.8) minutes vs. (36.3±3.3) minutes, t=3.389, P=0.003] and shorter abdominal incision length [(4.5±0.9) cm vs.(11.0±2.3) cm, t=13.244,P=0.004]. There were no significant differences between two groups in intraoperative blood loss [(92.9±22.4) ml vs. (87.0±7.3) ml,t=1.186,P=0.366], number of lymph node dissected (28.4±5.7 vs. 27.3±5.2, t=0.838, P=0.383), postoperative flatus time [(4.4±2.1) days vs.(4.2±1.8) days, t=0.391, P=0.563], morbidity of postoperative complication [4.3%(1/23) vs. 6.7%(3/45), χ²=0.148,P=0.701]. All the patients were followed up for 28±10 (10-46) months. There were no long-term complications, recurrence or death in two groups. Conclusion: Overlap anastomosis in Billroth I digestive tract reconstruction after laparoscopic distal gastrectomy is safe and effective, and can reduce the anastomosis time.

[Clinical analysis of conjunctival papilloma]

Objective: To summarize and analyze the clinical manifestation of conjunctival papilloma, its relationship with human papillomavirus (HPV) infection and the recurrence after the combination of operation and pharmacotherapy. Methods: A retrospective case series study. Analysis of 40 patients (41 eyes) with conjunctival papilloma treated at Peking Union Medical College Hospital from January 2008 to June 2018 was performed. All patients were given routine blood and urine, hepatitis B virus surface antigen, antibodies to hepatitis C virus, antibodies to human immunodeficiency virus and antibodies to Treponema pallidum testing, and HPV testing for the urethra epithelial tissue. Direct contact of the tumor with instruments was avoided during surgery, and freezing treatment was combined. HPV testing was performed for the resected conjunctival papilloma. Multiple medications were used after surgery. Results: In 40 cases with 41 eyes, there were 22 males (23 eyes) and 18 females (18 eyes). A single tumor was seen in 27 eyes, and multiple tumors were seen in 14 eyes. Thirteen patients (13 eyes) older than 50 years old had pedicel-free papillpma, and 27 patients (28 eyes) aged from 12 to 40 years had pedicel-type papillpma. All cases were confirmed by pathology as conjunctival papilloma, of which 9 cases showed moderate to severe atypical hyperplasia on squamous cells. The HPV test was positive in 17 out of the 40 cases (42.5%) of conjunctival papilloma. Urine test results of 16 patients (40.0%) were positive for occult blood and showed that urinary white blood cell was elevated. Of the 40 patients, 33 were newly diagnosed and 7 had a relapse. The average follow-up time was (37.4±11.9) months after combined therapy and no recurrence was found in any patients. Conclusions: Conjunctival papilloma is usually observed in people aged from 20 to 40 years and older than 50 years, and it often occurs in one eye. Its main pathological feature is benign tumors of the papillary hyperplasia on the conjunctival epithelial tissue. Some patients have atypical hyperplasia of squamous cells. The cause of the disease may be related to the infection of HPV and the urinary tract. Combined treatment can reduce the recurrence rate of conjunctival papilloma. (Chin J Ophthalmol, 2019, 55: 369-373).

[The clinical characteristics of 346 patients with IgG4-related disease]

Objective: To analyze the clinical characteristics of IgG₄-related disease (IgG₄-RD)so as to improve the understanding of IgG₄-RD in China. Methods: IgG₄-RD patients were recruited from Peking Union Medical College Hospital between January 2011 and January 2016. All patients were followed-up for more than 6 months. The demographic characteristics, symptoms, organ involvements, laboratory examinations and treatment efficacy were evaluated and analyzed. Results: A total of 346 patients were finally enrolled, including 230 males (66.5%) and 116 females (33.5%). The mean age of disease onset was (53.8±14.2) years old. The mostly common involved organs were lymph nodes (56.4%) and submandibular glands (52.6%). Other affected organs and manifestations included: swelling of the lacrimal glands (46.5%), autoimmune pancreatitis (38.4%), pulmonary involvement (28.0%), sclerosing cholangitis (25.4%), naso-sinusitis (23.4%), parotid gland swelling (21.7%), retroperitoneal fibrosis (19.9%), large arteries involvement (9.5%), kidney involvement (obstructive nephropathy caused by retroperitoneal fibrosis was excluded) (6.9%), skin lesions (6.4%). Rare features consisted of thyroid glands, pituitary glands, gastrointestinal tract, pachymeningitis, pericardium, sclerosing mediastinitis and orchitis. The majority of patients had multi-organ involvement, such as 74.3% patients with 3 and more, 18.2% and 7.5% patients with 2 and single organ involvement respectively. The average IgG₄-RD responder index (IgG₄-RD RI) was 13.21±5.70. History of allergy was found in 172 (49.7%) patients. As to the laboratory tests, elevated serum IgG₄ levels were confirmed in 285 (94.1%) patients, which was positively correlated with IgG₄-RD RI. There were 33.5% patients receiving monotherapy of glucocorticoid, 52.6% treated with glucocorticoids combined with immunosuppressive agents, 4.9% patients with immunosuppressant only, and 9.0% patients with mild disease not receiving medication. The majority (336, 97.1%) patients improved the above regimens. Conclusion: IgG₄-RD is a systemic fibro-inflammatory disease with multiple organ involvement. The mostly common involved organs include lymph node, submandibular glands, and pancreas. Glucocorticoids and immunosuppressive agents were effective for IgG₄-RD.

[Risk factors analysis for recurrence of the idiopathic benign paroxysmal positional vertigo]

Objective:To study the risk factors of recurrence in patients with benign paroxysmal positional vertigo(BPPV) after successful repositioning treatment. Method: Two hundred and two cases of confirmed BPPV patients, were followed-up for 10 months after particle repositioning, and the incidence of recurrence was analyzed. The risk factors for recurrence were analyzed by logistic regression. Result: 51 out of 202 confirmed BPPV patients complained of recurrence. There was significant difference of the duration of vertigo before treatment, the times of repositioning and SDS between the two group(P<0.05). While the sex, the age, the incubation period of BPPV, the duration time of BPPV, underlying diseases and the type of canal were not associated with the residual dizziness(P>0.05). Logistic regression analysis showed that the times of repositioning and the SDS were the risk factor for residual dizziness. Conclusion:The effective repositioning and the psychological care are very important to reduce the recurrence of BPPV.

[Glucocorticoids and liver diseases]

Glucocorticoids is a type of steroid hormone secreted from zona fasciculata of adrenal cortex.As an immune and inflammatory inhibitor, glucocorticoids has been used to treat many kinds of diseases.T cell response plays a crucial role in the pathogenesis of liver diseases. However, the role of glucocorticoids in the mechanism and treatment of liver disease in current clinical practice is controversial. This paper summarizes the progress of glucocorticoid use for the treatment of liver diseases in recent years. References will be provided for how to grasp the indications,application timing and proper dosage of glucocorticoids in liver diseases.

Induction of Thrombosis in a Mouse Model by IgG, IgM and IgA Immunoglobulins from Patients with the Antiphospholipid Syndrome

Antiphospholipid syndrome is a disorder of recurrent thrombosis and pregnancy losses associated with production of anticardiolipin antibodies and lupus anticoagulant positivity. Recently, we have adapted a mouse model of induced venous thrombosis to study the role of autoantibodies in thrombus formation. To determine whether immunoglobulins from patients with the antiphospholipid syndrome play a role in thrombosis, we injected groups of CDI mice either with immunoglobulins purified from seven patients with the antiphospholipid syndrome (nine preparations studied: four IgG, three IgM and two IgA) or with immunoglobulins of the same isotype from healthy controls. Seventy- two h after injection, a non-occlusive thrombus was induced in the femoral veins of experimental mice by a pinch injury; the thrombus areas as well as times of formation and disappearance of the thrombi were measured. Eight of the nine antiphospholipid syndrome immunoglobulin preparations caused a significant increase in mean thrombus area and a significant delay in mean thrombus disappearance time as compared with normal controls. To determine whether anticardiolipin antibodies might be involved, separate groups of mice were injected with affinity-purified IgG (n = 2) or IgM (n = 2) anticardiolipin antibodies or with normal immunoglobulins of the same isotype, and the effects on thrombus formation compared. Mean thrombus area and mean disappearance times were again significantly increased in all four groups injected with affinity-purified antibodies. This is the first study to show that anticardiolipin antibodies of IgG, IgM and IgA isotypes may play a role in thrombosis in vivo.

[Effects of phosphorus fertilizer application methods and types on the yield and phosphorus uptake of winter wheat.]

A field micro-plot experiment was conducted to determine the effect of different placement methods and types of phosphorus (P) fertilizer on winter wheat growth and phosphorus uptake. P fertilizer types included monocalcium phosphate (MCP) and diammonium phosphate (DAP). P fertilizer application methods included: 1) surface broadcasting (S); 2) banding 5 cm below seeds (B₀); 3) banding 5 cm below and 3 cm away from seeds (B₃); 4) banding 5 cm below and 10 cm away from seeds (B₁₀); 5) mixing with the 20% of the top soil below seeds (M). The result showed that B₀ had the best effect on increasing yield, reached 7.63 t·hm^-2 in MCP-B₀ and 7.99 t·hm^-2 in DAP-B₀, which increased 10.3% and 10.7%, respectively compared with surface broadcasting. B₁₀ had the lowest grain yield (6.60-6.77 t·hm^-2). The total P uptake by wheat in B₀ and M was at a relatively high level (34.42-35.60 kg·hm^-2), B₁₀ performed worst at all growth stages of wheat, while P uptake of DAP-B₁₀ was 11.9% higher than MCP-B₁₀. These results indicated that concentrating P fertilizer in a short distance near the seeds was an optimized application method for winter wheat in this region, and DAP performed better than MCP on P uptake and utilization of wheat under far banding.

[Comparison of early clinical effects of ablation with surgery treatment in patients with hypertrophic cardiomyopathy]

Objective: To compare the early clinical effect of septal myectomy and percutaneous transluminal septal myocardial ablation (PTMSA) on the left ventricular outflow obstruction and the rate of complication in patients with hypertrophic obstructive cardiomyopathy (HOCM). Methods: A total of 204 patients with HOCM who received septal reduction treatment were recruited. These patients were divided into two groups, surgery group (n=135) (65 patients with modified Morrow procedure, 70 patients with non-Morrow myomectomy) and PTMSA group (n=69). The baseline characteristics, disease status, other history of surgery and echocardiography parameters before and after septal reduction were collected, as well as the complication within 1 week after operation. Results: The mean age in surgery group was (46±14) years old, with 76 males (56.3%); mean age was (47±11) years old and with 51 males (73.9%) in PTMSA group. There was no significant difference in age, gender, the time of symptom and diagnosis, syncope, family history and atrial fibrillation between the two groups (all P>0.05). The proportion of mitral valve prolapse in the surgery group was higher than that in PTMSA group (75.8% vs 44.2%, P<0.05). Baseline left ventricular outflow tract (LVOT) gradient was comparable (82.7 mmHg in surgery group vs 77.7 mmHg in PTMSA group, P>0.05). The mean resting LVOT gradient after septal reduction therapy was lower (16.55 mmHg in surgery group, 26.68mmHg in PTMSA group) than that before operation, with lower gradient in surgery group (P<0.05). Compared with PTMSA group, the duration of hospitalization was longer in surgery group (P<0.05). There was similar rate of operation related complications in the two groups. Conclusions: Both septal reduction therapies can improve the LVOT obstruction, more significant in surgery group, but with longer hospital stay. The rate of operation related complication is similar in both groups.

[Prediction of occupational allergic contact dermatitis induced by formaldehyde by IL17/IL22 secretion cell rest combined with patch test]

Objective: To investigate the possible role of IL17-and IL22-secreting cells combined with patch test for the prediction of formaldehyde-induced occupational allergic contact dermatitis(OACD). Methods: From October 2014 to October 2016, totally 131 formaldehyde-exposed workers(49 cases with inflammatory skin lesions,82 ones without inflammatory skin lesions)and 63 non-exposed health controls were recruited. Patch-test was performed in 49 cases of formaldehyde-exposed workers with inflammatory skin lesions. Circulating IL17+and IL22+Tcell subsets were assessed by flow cytometry(FCM). Results: Among 49 cases of formaldehyde-exposed workers with inflammatory skin lesions,32 cases were with positive patch-test while 17 cases with negative patch-test. The proportions of circulating CD3+CD8-IL17+ and CD3+CD8-IL22+ cells from patch-test(+) formaldehyde-exposed workers were significantly higher than that of patch-test(-)group, formaldehyde-exposed workers without skin lesions and non-exposed controls(P<0.05). The proportions of circulating CD3+CD8-IL17+ and CD3+CD8-IL22+cells from patch-test(-)group and formaldehyde-exposed workers without skin lesions were also higher than that of non-exposed controls(P<0.05). But there was no significant difference between patch-test(-)group and formaldehyde-exposed workers without skin lesions(P>0.05). Peripheral CD3+CD8+IL17+and CD3+CD8+IL22+cells were also detected in spite of small amounts. The percentages of CD3+CD8+IL17+and CD3+CD8+IL22+ cells inperipheral blood from patch-test(+)formaldehyde-exposed workers were enhanced significantly, compared to patch-test(-)group, formaldehyde-exposed workers without skin lesions and non-exposed controls(P<0.05). The proportions of circulating CD3+CD8+IL17+ and CD3+CD8+IL22+ cells from patch-test(-)group and formaldehyde-exposed workers without skin lesions were significantly higher than that of non-exposed controls(P<0.05). But there was no significant difference between patch-test(-) group and formaldehyde-exposed workers without skin lesions(P>0.05). Conclusion: The proportions of circulating IL17+ and IL22+T cells(both CD8-and CD8+)are enhanced in formaldehyde-exposed workers at proposed OEL, possibly involved in the development of formaldehyde-induced OACD.The detection of IL17-and IL22-secreting cells combined with formaldehyde patch test help to screen the workers with allergy property and prevent OACD.

Propranolol inhibits the proliferation, migration and tube formation of hemangioma cells through HIF-1α dependent mechanisms

The aim of this study was to investigate the mechanism of propranolol on the regression of hemangiomas. Propranolol-treated hemangioma tissues were collected and the expression of hypoxia inducible factor-1α (HIF-1α) was examined. We also established HIF-1α overexpression and knockdown hemangioma cells, and determined the effects of HIF-1α on the hemangioma cells proliferation, apoptosis, migration and tube formation. Significantly increased HIF-1α level was found in the hemangioma tissues compared to that in normal vascular tissues, whereas propranolol treatment decreased the HIF-1α level in hemangioma tissues in a time- and dose-dependent manner. Moreover, propranolol treatment significantly decreased cell proliferation, migration and tube formation as well as promoted cell apoptosis in HIF-1α overexpression and knockdown hemangioma cells. Propranolol suppressed the cells proliferation, migration and tube formation of hemangioma cells through HIF-1α dependent mechanisms. HIF-1α could serve as a novel target in the treatment of hemangiomas.

[Prevalence and treatment effects of Demodex species in eyelash follicles in patients with meibomian gland dysfunction]

Objective: To investigate the prevalence and treatment effects of Demodex species in eyelash follicles in patients with meibomian gland dysfunction (MGD). Methods: The MGD patients (MGD group) and normal subjects (control group) were collected from the Ophthalmology Clinic in PUMCH from July 2015 to December 2015. The symptom score of MGD patients was recorded. Eyelash sampling, Demodex counting, tear film break-up time (BUT), cornea fluorescein staining (Fl) and Schirmer test Ia (S Ⅰ aT) were measured for both groups. All the measurements were repeated after 4 weeks of meibomian function treatment for the MGD group. Symptom score, BUT, Fl and S ⅠaT were normally distributed and displayed as mean± standard deviation. Demodex counting was not normally distributed and displayed as median (interquartile range P25, P75). Results: Forty-four MGD patients (88 eyes) and 48 controls (96 eyes) were recruited. For the MGD and control groups, the number of Demodex was 3.5 (2, 7) and 0 (0, 7), respectively (Z =-4.912,P= 0.000). The percentage of Demodex infestation was 86.4% and 39.6%, respectively (χ(2)=35.957, P=0.000). The BUT was (3.57±2.09) s and (10.17±3.25) s, respectively (t=-5.154, P=0.000). The Fl was 2.73±1.23 and 0.85± 0.33, respectively (t=4.583, P=0.000). The SⅠaT was (8.75±5.61) s and (14.51±5.29) s, respectively (t=-2.278, P=0.028). The symptom score of the MGD group before and after treatment was 4.77 ± 3.01 and 2.79 ± 2.01, respectively (t=6.224, P=0.000). The BUT, Fl and number of Demodex of the MGD group after the treatment were (5.43±2.37)s, (1.91±0.66) and 2 (0, 3), respectively, and all had significant difference with the data before the treatment (BUT, t=-4.705, P=0.000. Fl, t =3.902, P =0.000. number of Demodex, Z=-4.623, P =0.000). The S Ⅰ aT of the MGD group after the treatment was 8.86 ± 6.76, with no significant difference with the data before the treatment (t=-0.277, P=0.833). Conclusions: The Demodex infestation has some effects on the pathogenesis of MGD. The treatment of MGD may help to decrease the number of Demodex and thus relieve the ocular discomfort.(Chin J Ophthalmol, 2017, 53:193-197).

Integrative Profiling of Bee Communities from Habitats of Tropical Southern Yunnan (China)

Understanding and managing pollination service is hindered by taxonomic impediments and paucity of data, particularly in the tropics. Herein we apply integrative species delineation and taxonomy to test impacts of land use on the diversity of bee communities within Xishuangbanna (Yunnan, south China), a highly biodiverse tropical region which has undergone extensive land conversion to rubber plantation. 128 Operational Taxonomic Units (OTU) were inferred by an iterative and integrative approach. Bee activity differed significantly across land use samples, although community composition corresponded more to level of vegetation density, when accounting for spatial structure. Species diversity was high in young rubber plantations, although composition overlapped with other species-rich habitats (natural forest edge and river banks), and older plantations (>8 years) showed very low diversity under all measures. Community structures were similar between the natural forest interior and edge, although analysis indicated contrasting drivers of diversity, with clustering in the interior and overdispersion in the forest edge. Further, phylogenetic diversity and derived indices were underestimated when reference data were omitted from analysis. The description of bee communities herein permits more informed choices in land management with respect to ensuring continuation of essential services by bees.

[Prevalence of hearing disorders in China: a population-based survey in four provinces of China]

Objective: To investigate the prevalence, severity of hearing disorders and demographics of people with hearing disorders based on the whole population in Jilin, Guangdong, Shannxi and Gansu provinces in China. Methods: According to " WHO Ear and Hearing Disorders Survey Protocol" , 144 clusters were chosen with probability proportional sampling(PPS) method from the four provinces covering 194, 688, 061 residents. Audiological test, otological examination and questionnaire surveying were conducted for all samples from August, 2014 to September, 2015. The hearing disorders were classified according to WHO criteria and classification. Results: Among 47 511 targeted residents, 45, 052 individuals (94.82% response rate) participated in the survey. The standardized prevalence rates of hearing disorders and disabling hearing disorders were 15.84 % and 5.17 % respectively. Almost 50% of people with hearing disorders had no awareness of it or its starting time. There was significant difference in the prevalence among people of different ages, genders, occupations, provinces, marital status and education levels. The prevalence of hearing disorders increased significantly as age grew. People above 60 years old occupied 55.31% of the total hearing disorders. The prevalence of hearing disorders among male, people of low education and those who lost husband or wife, as well as workers and farmers was relatively higher. Conclusions: The prevalence of hearing disorders is high, and hearing disorders are " invisible" . Demographics and socioeconomic factors significantly influence the prevalence of hearing disorders.

[Effects and related mechanism of quercetin on thrombin-induced proliferation and migration of rat vascular smooth muscle cells]

OBJECTIVE

To investigate the effects and related mechanism of quercetin on thrombin-induced proliferation and migration of rat vascular smooth muscle cells(VSMCs).

METHODS

Third to fifth generation VSMCs were divided into three groups, including control group (with PBS on the base of medium DMEM), thrombin group (with 1 U/ml thrombin on the base of medium DMEM) and quercetin group (treated with 100 μmol/L quercetin before 1 U/ml thrombin on the base of medium DMEM). The proliferation and migration capacitities were tested by CCK-8 kit and transwell chamber, respectively. The protein level of phospho-extracellular signal regulated kinase 1/2 and phosphor-p38 were measured by Western blot.

RESULTS

(1) According to the CCK-8 results, optical density value was significantly higher in thrombin group than that of control group(2.59±0.16 vs. 1.97±0.18, P<0.01), which could be significantly attenuated by pretreatment with quercetin(2.13±0.19, P<0.01), and there was no significant difference between quercetin group and control group(P>0.05). (2) The transwell results showed that the migrated VSMCs were significantly higher in thrombin group than in control group (1 337±162 vs. 99±26, P<0.01), which could be significantly reduced by pretreatment with quercetin (926±111, P<0.05), but still significantly higher than control group (P<0.01). (3) The protein expressions of phospho-extracellular signal regulated kinase 1/2 and phosphor-p38 were significantly upregulated in thrombin group compared to control group (both P<0.05), which could be significantly downregulated by pretreatment with quercetin (P<0.05).

CONCLUSION

Quercetin can effectively attenuate thrombin-induced vascular smooth muscle cells proliferation and migration, possibly through inhibiting the phosphorylation of extracellular signal regulated kinase 1/2 and p38 pathway.

[Experimental study on the in vitro osteogenic differentiation of dental pulp stem cells encapsulated in Pluronic F-127 hydrogel]

OBJECTIVE

To evaluate the biocompatibility and viability of nonionic triblock copolymer Pluronic F-127 as a cell scaffold for osteogenic differentiation of dental pulp stem cells(DPSC).

METHODS

DPSC were obtained via enzymatic digestion method and purified bylimited dilution method. The freeze dried hydrogel of 20% Pluronic F-127 was prepared and itsstructurewas observed usingscanning electron microscopy(SEM). After the encapsulation of cells of passage 3 in Pluronic F-127, the effects of hydrogel on the proliferations of DPSC were assessed with methyl thiazolyl terazolium(MTT) after one day and 3, 5, 7 days of incubations, respectively. On day 14, osteogenic abilities of DPSC encapsulated in the hydrogel were estimated by means of alizarin red S, immunocytochemical staining and real-time quantitative PCR(RT-qPCR).

RESULTS

DPSC were isolated and cultured successfully in the present study. SEM observations showed that porous structures which might be suitable for cell culture. A570 values of MTT were then normalized. A570 values of the cells in 2D cultures were 0.30±0.06, 0.30±0.17, 0.35±0.04 and 0.25±0.06 and A570 values of DPSC in 3D cultures were 0.36±0.06, 0.54±0.18, 0.70±0.10 and 0.32±0.10 on day 1, 3, 5 and 7, respectively. A570 value peaks were found on day 5 in both groups. The proliferation of 3D cultured DPSC was higher than that of 2D cultured cells(P<0.05). After 14 days of osteogenic induction, there were no calcium nodules observed in the control group and the numbers of calcium nodulesin the 2D and 3D groups had no significant difference(P>0.05). Inmmunocytochemical staining demonstrated strong expression of osteoblast marker Runt-related transcription factor 2(RUNX2), type Ⅰ collagen(Col-Ⅰ) and relatively low expression of osteocalcin(OCN). Moreover, RT-qPCR showed no differences between the relative expression of ALP, RUNX-2, OCN in the 2D and 3D groups (P>0.05), but a higher relative expression of Col-Ⅰ was observed in the 3D group(P=0.023).

CONCLUSIONS

Pluronic F-127 is a promising cell scaffold or cell carrier for the osteobalst differentiation of dental pulp stem cells.

Role of microRNA-129-5p in osteoblast differentiation from bone marrow mesenchymal stem cells

Mesenchymal stem cells derived from bone marrow have the capacity to differentiate into osteoblast, chondrocyte, nerve cell and myocardial cell in vitro, which are an ideal engraft in tissue-engineered repair. Osteoblast differentiation is a vital process in maintaining bone homeostasis in which various transcriptional factors, including signaling molecules, and microRNAs (miRNAs). In this research, human bone marrow mesenchymal stem cells (hBMSCs) were induced differentiation into osteoblast in vitro after over-expression of miR-129-5p. The results showed that the hBMSCs could induce differentiation into osteoblast under the special condition medium, but when the miR-129-5p was over-expressed in hBMSCs, the differentiated efficiency and induced time of osteoblast from hBMSCs could be promoted. This reason was demonstrated that signal transducer and activator of transcription 1 (STAT1) was a transcriptional repressor of osteoblast gene (Runx 2) expression during osteoblast differentiation, miR-129-5p reduced STAT1 levels, leading to the accumulation of correctly spliced Runx 2 mRNA and a dramatic increase in Runx 2 protein.

Dihydromyricetin induces cell apoptosis via a p53-related pathway in AGS human gastric cancer cells

The aim of the present study was to determine the anti-proliferative and pro-apoptotic effects of dihydromyricetin (DHM) on the AGS human gastric cancer cells and their underlying mechanisms. The effects of DHM on AGS cells were evaluated by using 3-(4, 5-di-methylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), lactate dehydrogenase, and Annexin V/propidium iodide (PI) double-staining assays. The underlying mechanisms were determined by using quantitative real-time polymerase chain reaction. The results demonstrated that DHM significantly (P < 0.05) inhibited AGS cell proliferation and induced cell cytotoxicity in a dose- and time-dependent manner. Additionally, Annexin V/PI double-staining assay showed that DHM promoted cell apoptosis in both, early and late stages. Furthermore, DHM also regulated the expression of apoptotic genes such as p53 and B-cell lymphoma-2 (bcl-2) in a dose- and time-dependent manner. In conclusion, this is the first report demonstrating the anticancer and pro-apoptosis effects of DHM on AGS human gastric cancer cells. The results strongly suggest that DHM may be a potential therapeutic candidate for the treatment of gastric cancer.

Effect of new-pattern obstetrical nursing in reducing cesarean delivery rate

Spontaneous labor is the preferred delivery way ensuring health of fetus. However, recently, more and more puerperae tend to choose cesarean. However, cesarean delivery is likely to induce various short-term and long-term potential complications, severely threatening maternal and child health. To discuss the clinical effects of new-pattern obstetrical nursing in reducing cesarean delivery rate, 680 primiparas who delivered between December 2011 and December 2013 were selected from Beijing Obstetrics and Gynecology Hospital, Capital Medical University, China as research subjects. They were randomly divided into an observation group (n=340) and a control group (n=340). Primiparas in the observation group were taken care of by new-pattern nursing measures during pregnancy and the puerperal period, while primiparas in the control group received traditional nursing measures. Cesarean delivery rate was compared between two groups. Cesarean delivery rate was statistically significant between the observation group and the control group (21.8% vs 32.9%) (P less than 0.05). Also, it was found that, the incidence rate of perioperative complications of the observation group was much lower than the control group, and the difference was statistically significant (P less than 0.05). The findings suggest that new-pattern obstetrical nursing is effective in reducing the cesarean delivery rate, therefore is worth promoting and applying in clinical practice.

A survey on the developmental intestinal microbiota research in China: The history, funding, and frontiers of gut bacteria

Up to 100 trillion bacteria are harbored in the human intestine with a mutualistic and interdependent relationship with the host during a long period of co-evolution. The so-called intestinal microbiota (IM) fulfill important metabolic tasks and the impaired stability may lead to IM-related diseases, including inflammatory bowel disease (IBD), colorectal cancer (CRC), metabolic syndrome (MS), liver diseases, and so on. Here, we review the past and development of IM research in China, including the achievements that Chinese researchers have made both in basic and clinical scientific field. Moreover, we evaluate the contributions of the National Natural Science Foundation of China (NSFC), the 973 National Basic Research Program of China (973 Program), the 863 National High Technology Research and Development Program of China (863 Program), and funds from the public health industry in the field of IM research.

An inexact multi-objective programming model for water resources management in industrial parks of Binhai New Area, China

In recent years, Binhai New Area of Tianjin has been suffering severe water shortage due to climate change and industrial activities. Integrated and effective water resources management approaches are urgent for the sustainable development of industrial parks in Binhai New Area. However, uncertainties exist in many aspects of the water resources system and are inevitably problematic for water resources planning and policy-making. To address these uncertainties, an interval multiple-objective programming model was developed here to support the long-term planning of industrial water resources management in Binhai New Area, Tianjin, China. The model incorporated both multiple-objective programming and interval linear programming into a general programming framework. The developed model could handle the uncertainties and complexities of the water management system, and also allowed decision makers to adjust fuzzy objective control decision variables to satisfy multiple holistic and interactive objectives. The solutions are useful for planning adjustments of the existing water allocation patterns in Binhai New Area.

The application of high definition flow imaging in fetal hemodynamics

OBJECTIVE

This work aims to investigate the application of high definition flow imaging (HD-flow) in fetal hemodynamics, and establish reference range of hemodynamic parameters in fetal with different gestational ages.

MATERIALS AND METHODS

A thousand of normal pregnant women were divided into five groups: 18-22, 23-27, 28-32, 33-37, and 38-40 gestational weeks. Color Doppler flow imaging (CDFI) and HD-flow were adopted to display the heart structure and measure the blood flow velocity. The pulmonary vein display results were scored. The results of HD-flow and CDFI were compared.

RESULTS

The catheter peak velocity of fetal mitral, tricuspid, aortic, pulmonary artery, aortic arch, ductal arch, the inferior vena cava, pulmonary vein, and venous catheter increased continuously with the increase of gestational age, showing a linear correlation. HD-flow was superior to CDFI on the display of pulmonary vein in 18-22, 23-27, and 28-32 weeks (p < 0.05), but was not in 33-37 and 38-40 weeks. HD-flow was an accurate positioning method for the pulmonary veins.

CONCLUSION

HD-flow can make accurate evaluation of fetal hemodynamics and the demonstration of low blood flow, such as pulmonary venous, is better than CDFI. Pulmonary veins can be accurately positioned with HD-flow. HD-flow can demonstrate the main blood vessels of the whole fetal circulation and can display the spatial relationship of the blood vessels. It is of important clinical significance in hemodynamic study.

Effect of early fluid resuscitation on the lung in a rat model of lipopolysaccharide-induced septic shock

BACKGROUND

Many clinical trials have showed that early fluid resuscitation can improve the prognosis and reduce the mortality rate of patients with septic shock. However, some experiments suggest that abundant fluid may injure the lung and other tissues.

AIM

To evaluate the protective effect of early fluid resuscitation and simultaneous norepinephrine treatment on lung function by using the rat model of lipopolysaccharide (LPS)-induced septic shock.

MATERIALS AND METHODS

Male Wistar rats were randomly divided into four groups: normal control group, septic shock control group, early fluid resuscitation treatment group, early fluid resuscitation and simultaneous norepinephrine treatment group. Blood gas, lactate, fluid volume, and dose of norepinephrine were recorded. Pathological change was observed by hematoxylin and eosin staining and transmission electron microscopy. The activities of hydroxyl radicals, MDA, SOD and MPO were detected by spectrophotometry. The expression of IL-6, IL-8, and TNF-alpha were determined with ELISA kits.

RESULTS

LPS could induce rats to suffer from acute lung injury in early stage of septic shock. Early fluid resuscitation could guarantee effective circulating blood volume and tissue perfusion pressure, improve microcirculatory derangements, increase oxygen partial pressure and oxygenation index, but have the tendency to aggravate pulmonary edema. Simultaneous norepinephrine treatment in early stage could decrease the fluid volume, alleviate the degree of pulmonary edema, reduce the expression level of pro-inflammatory mediators in the serum and BALF, and increase the oxygenation index.

CONCLUSIONS

Early fluid resuscitation and simultaneous norepinephrine treatment may be a superior alternative to protect lung injury secondary to septic shock.

Status epilepticus stimulates peroxisome proliferator-activated receptor γ coactivator 1-α/mitochondrial antioxidant system pathway by a nitric oxide-dependent mechanism

Peroxisome proliferator-activated receptor (PPAR) γ coactivator 1-α (PGC-1α) is a transcriptional coactivator identified as an upstream regulator of lipid catabolism, mitochondrial number and function. PGC-1α protects neurons against oxidative damage by inducing several members of the mitochondrial antioxidant system such as superoxide dismutase 2 (SOD2) and uncoupling protein 2 (UCP2). Its role in seizure-induced oxidative stress has not been studied. Here we showed that pilocarpine-induced status epilepticus (SE) stimulates the PGC-1α/mitochondrial antioxidant system signaling pathway in the rat hippocampus. Because nitric oxide (NO) is the key factor of mitochondrial biogenesis through the transcriptional induction of PGC-1α, we investigated whether NO is involved in activation of the PGC-1α/mitochondrial antioxidant system after SE. Treatment with the NO synthase (NOS) inhibitor N(G)-nitro-l-argininemethyl ester (l-NAME) attenuated the increased expression of the PGC-1α/mitochondrial antioxidant system after SE and enhanced oxidative stress. These results suggest that SE can induce the PGC-1α/mitochondrial antioxidant system signaling pathway, which may represent a protective mechanism against SE-induced oxidative stress. Furthermore, NO may positively regulate the mitochondrial antioxidant system by inducing PGC-1α in pilocarpine-induced SE.

Beyond medical insurance: delayed or forgone care among children in Chinese immigrant families

While Asian Americans are less likely than most Americans to use health services, little is known about their barriers to pediatric care. This study seeks to describe the prevalence of delayed/forgone pediatric care and its association with parental acculturation status in recent-immigrant Chinese families. Survey data were obtained from 76 families across two community services sites. Half of the surveyed families reported delayed/forgone pediatric care in the previous 12 months. Low-income families in suburban areas reported greater financial burdens, linguistic barriers, and a higher prevalence of delayed/forgone care than low-income families living in downtown area. Middle class immigrant families reported cultural barriers as a reason for delayed/forgone care. Traditional beliefs and not medical insurance were significant predictors of delayed/forgone care. Culturally and linguistically appropriate studies on risk reduction interventions will be needed to address the linguistic and cultural barriers to health care access.

A study of the size-dependent elastic properties of ZnO nanowires and nanotubes

We present our calculations of the Young's modulus of ZnO nanowires and nanotubes by using the empirical Buckingham-type potential. Our results indicate that the Young's moduli of ZnO nanowires increase as the diameters decrease, and the Young's moduli of ZnO nanotubes increase as the thicknesses decrease. Furthermore, we find that such size-dependent elastic properties mainly arise from the lateral facets of the nanowires and nanotubes. In particular, for a ZnO nanotube with a thin wall, the Coulomb interaction between the ions of the outer and inner atomic layers plays an important role in the Young's moduli of the surface atomic layers.

Targeting specificity and pharmacokinetics of asialoorosomucoid, a specific ligand for asialglycoprotein receptor on hepatocyte

OBJECTIVE

To testify that the asialoorosomucoid (ASOR) prepared by us has liver-targeting specificity and to investigate its pharmacokinetic characteristics.

METHODS

The distribution of 125I-ASOR in vivo was determined by single photon emission computed tomography (SPECT) and immunohistochemical technique after 125I-ASOR was injected into Sprague-Dawley (S-D) rats through their caudal veins. In vitro, different doses of pEGFP-N1 plasmid were transfected into both HepG2 cells and HT1080 cells with the use of ASOR-poly-L-lysine. At 24 and 48 h after transfection, the expression of green fluorescent protein (GFP) was determined under fluorescent microscope. Pharmacokinetic parameters were calculated according to two-compartment open system model with first-order kinetics.

RESULTS

SPECT images showed that 125I-ASOR was located only in liver/stomach and root of caudal vein/bladder at 10 min after injection. The 125I-ASOR radioactivities of organs taken out from S-D rats were different at different times, and about 63% of 125I-ASOR was located in the liver at 10 min after injection. At 30 min after injection a peak of radioactivity was seen in stomach. The times of these two radioactivity peaks were different. Immunohistochemical study of liver frozen sections showed that ASOR was combined mainly with hepatocyte membrane, especially in areas with rich blood flow. In vitro study showed that ASOR targeted specifically cells with asialoglycoprotein receptor (ASGr). GFP expression was detected in HepG2 cells but not in HT1080 cells. Furthermore, the more quantity of pEGFP-N1 transfected and the longer expression time, the higher GFP expression level was in HepG2 cells. The 125I-ASOR pharmacokinetics equation for liver was Ct=662216e-3.362t+8896e-2343t. 125I-ASOR was excreted from liver slowly after an initial rapid decrease. The pharmacokinetic equation for stomach was Ct=-114815e-1.7t+1148153e-15t and the half-life of 125I-ASOR in stomach was 4.62 h.

CONCLUSIONS

ASOR prepared by us could be an efficient gene transfer vector, ASOR was distributed mainly in the liver and stomach and had high targeting specificity to hepatocytes or hepatic originating cells.

Dosimetric analysis of a shielded applicator for nasopharyngeal carcinoma intracavitary brachytherapy: Monte Carlo calculation

In nasopharyngeal cancer (NPC) intracavitary brachytherapy, an anatomical dose reference point (in line with that for gynecology work), e.g., at the sphenoid floor, is more precise than the empirical point of 1 cm from the source. However, such increases of the single-source-plan treatment distances may deliver excessive doses inferiorly, to the soft palate. As shielding may help, its efficacy was studied by Monte Carlo simulations in water for 20 and 30 mm diameter spherical NP applicators (representing extremes of sizes for the small NP cavity), with/without lead shielding inferiorly, using a single linear Ir-192, 2 mm steps, equal dwell times for 5 (5DP) and 9 dwell positions (9DP). Dose reductions of the selected points of interest ranged from 1.2% to 40.5% for the 20 mm shielded applicator and a range of 2.9% to 17.9%, for the 30 mm shielded applicator. Dose volume histograms of the "region of interest" (ROI)-a cuboid of 4 x 4 x 0.5 cm3 at the most inferior aspect of the applicator, also differed significantly. The highest doses of the 50% (D50) and 20% (D20) volumes of ROI (for 5DP and 9DP plans) were reduced by 11.9% to 17.9% for the 20 mm applicator and a range of 9.0% to 11.5% for the 30 mm shielded applicator. Doses in unshielded directions were insignificantly changed, for example, with a 20 mm applicator simulated in a 5DP plan, the dose distribution close to the source in the unshielded direction has less than 4% difference at the 50% isodose relative to the dose prescription point. For the 30 mm shielded applicator, despite smaller dose reduction percentages, a more pronounced effective dose reduction was obtained than nominal values when considering radiobiological equivalent doses. Our system was demonstrated to be ready for clinical assessment.

Modulation of the molecular conformation of a hepatocyte-targeting gene drug in order to improve its expression efficiency in vitro

AIM

To construct different conformations of a plasmid DNA/vector complex (pcDNA3.1/IFN-gamma-ASOR-PLL) and transfect cells of the hepatoma cell line BEL7402 to investigate the optimal conformation of the complex for improved expression efficiency in the target cell.

METHODS

Double-distilled water and adjuvant were added to the naked pcDNA3.1/IFN-gamma, target vector ASOR-PLL and the ASOR-PLL-pcDNA3.1/IFN-gamma complex to create different conformations; molecules that were transfected into BEL7402 cells and the expression efficiency was determined by measuring the IFN-g concentration in the culture supernatant by ELISA.

RESULTS

Naked pcDNA3.1/IFN-gamma DNA distributed linearly in double-distilled water and condensed into a mica configuration in adjuvant; ASOR-PLL had a net-like distribution without adjuvant and a spider-like form in the adjuvant-treated group; the ASOR-PLL-pcDNA3.1/IFN-g complex had a divaricate form without adjuvant, but a bead-like or granular conformation in 0.1 and 0.2 mol/L of adjuvant, a homogeneous bacilliform or chromatoid-shaped conformation in 0.3 mol/L adjuvant, and varied shapes in 0.4 and 0.5 mol/L adjuvant. The supernatant IFN-gamma expression in the bacilliform/chromatoid conformation complex group was the highest among the different conformation groups and controls. When chloroquine was added the supernatant IFN-gamma concentration increased in the liposome group and decreased in the bacilliform/chromatoid conformation group .

CONCLUSIONS

The two structural molecules and their complex, ASOR-PLL-pcDNA3.1/IFN-gamma, were adjustable in the liquid mode. The specific bacilliform/chromatoid conformation of complex was lysosome enzyme-resistant and could play an active role in improving the efficiency of gene expression. The hypothesis that a chromosome-like conformation of the target gene molecule is involved in enhancing exogenous gene expression is proposed.

Resonant field emission through amorphous diamond thin films (a model study)

A model for field emission through an amorphous diamond thin film with defects is constructed. Theoretical study shows that the emission is enhanced by attractive defects which would make the resonant emission observable for films with thickness of about 10nm. The emitted current density in typical parameters is calculated as functions of thickness, field strength and defect density. The energy distribution of emitted electrons is attained.

A double cysteine trkA mutant exhibiting reduced NGF binding and delayed Erk signaling

The NGF receptor trkA is a tyrosine kinase receptor comprising an extracellular domain with a ligand-binding site, a transmembrane-spanning domain (TMD), and an intracellular domain composed of a juxtamembrane region (JMR), a tyrosine kinase domain, and a short carboxy-terminal tail. Nerve growth factor (NGF) binds and activates this receptor, leading to phosphorylation of signaling substrates involved in neuronal proliferation, differentiation, and survival. Human trkA contains one cysteine residue in the TMD (C423) and another, separated by 12 residues, in the JMR (C436). We hypothesized that the removal of one or both of the cysteines would affect NGF-induced signaling of the trkA receptor. Here we show that NGF induces rapid receptor autophosphorylation in a wild-type, trkA-expressing clone (WT11), in a single cysteine trkA mutants (C423T or C436A), but lower autophosphorylation activity in a double-cysteine trkA mutant (C423T/C436A). WT11 and SM cells had similar binding affinity, but that of DM cells was lower, according to the NGF radioreceptor assay. NGF-induced Erk phosphorylation was rapid in WT11 and C423T cells, but delayed in C436A and C423T/C436A cells. NGF induced [3H]thymidine incorporation into WT11 and SM cells, but had no effect on DM cells. However, basic fibroblast growth factor (bFGF) induced rapid phosphorylation of Erk1/2, and [3H]thymidine incorporation in NIH3T3, WT11, single mutant (SM), and double mutant (DM) cells, suggesting that the impaired NGF-induced Erk phosphorylation and thymidine incorporation observed in DM cells are due to the double-cysteine mutations in the trkA receptor. Cumulatively, our findings support a model in which Cys436 of the trkA is responsible for the rapid transfer of the transmembrane occupancy signal to the SHC adaptor protein for activation of the Ras-Erk pathway and DNA synthesis.

[Determination of aluminium and barium in silicon-aluminium-barium alloy with internal standard by ICP-AES]

A method for the determination of aluminium and barium in silicon-aluminium-barium alloy with the internal standard by ICP-AES was studied. The method of melting sample, the interference of dissolved acid and coexisting elements and the working parameters were experimented. The sample was melted by appropriate acid, was changed into solution, the calculating lines were made by standard solution of aluminium and barium, then the concentrations of aluminium and barium were determined by ICP-AES. The linear rang, detection limits and RSD of the method were examined. The method was simple and the results were accurate.