Pulley Effect in the Capture of DNA Translocation through Solid-State Nanopores.

Nanopores are powerful single-molecule sensors for analyzing biomolecules such as DNA and proteins. Understanding the dynamics of DNA capture and translocation through nanopores is essential for optimizing their performance. In this study, we examine the effects of applied voltage and pore diameter on current blockage, translocation time, collision, and capture location by translocating λ-DNA through 5.7 and 16 nm solid-state nanopores. Ionic current changes are used to infer DNA conformations during translocation. We find that translocation time increases with pore diameter, which can be attributed to the decrease of the stall force. Linear and exponential decreases of collision frequency with voltage are observed in the 16 and 5.7 nm pores, respectively, indicating a free energy barrier in the small pore. Moreover, the results reveal a voltage-dependent bias in the capture location toward the DNA ends, which is explained by a "pulley effect" deforming the DNA as it approaches the pore. This study provides insights into the physics governing DNA capture and translocation, which can be useful for promoting single-file translocation to enhance nanopore sensing.

Preparation of three-dimensional matrices of human gingival tissue and comparison of induction of mesenchymal and blastema stem cell behaviors in prepared scaffolds.

This study aimed to compare the behavior of rat bone marrow mesenchymal stem cells and rabbit auricle blastema cells implanted in non-cellular gingival tissue scaffold of human. In this regard, the tissues obtained from gingival surgeries in the dental clinic were de-cellulated using two detergents of sodium dodecyl sulfate and triton 100-X. After washing and sterilization, they were used as a scaffold for culture with bone marrow mesenchymal stem cells of rats. Using light and electron microscopy, these scaffolds were examined before and after 1, 2, and 4 weeks of cell culture. Also, the prepared three-dimensional scaffold was placed in the blastema ring obtained from the rabbit earlobe punch. The samples were evaluated 1, 2, and 4 weeks after culture based on histology techniques. The results showed that the study of scaffolds by electron microscopy showed preserving the epithelium matrix and the collagen fibers in the tissue. Structures similar to the epithelium were created in both samples. In addition, induction of cellular secretion was observed in scaffold cells migrating to the scaffold. In general, scaffolds made from human gums can be a good platform for studying cellular behaviors. Of course, further experiments to determine the nature of differentiated cells can help advance our knowledge of matrix cell interactions.

Stress, anxiety and depression perceived by couples with recurrent miscarriage.

AIM: Recurrent miscarriage is considered a major life event. The main purposes of this study were to compare the differences in stress, anxiety, social support, sleep quality and depressive symptoms in couples experiencing recurrent miscarriage compared to peers who experience full-term normal childbirth in southern Taiwan. METHODS: Convenience sampling and snowball sampling were used respectively to recruit 78 couples with and 80 couples without recurrent miscarriage from October 2014 to July 2015. Five structured questionnaires including Perceived Stress Scale, State- Anxiety Inventory, Interpersonal Support Evaluation List, Pittsburgh Sleep Quality Index and Edinburgh Depression Scale were administered. RESULTS: Women who experienced recurrent miscarriage perceived significantly higher levels of stress, anxiety and depressive symptoms than their husbands. Women in the recurrent miscarriage group reported significantly greater depressive symptoms than women of the other group. A stepwise multiple regression analysis indicated key predictors of depressive symptoms among women of childbearing age, accounting for 62.9% of the variance, were anxiety, stress, social support and history of recurrent miscarriage. CONCLUSION: Women with recurrent miscarriage suffer mild to moderate depressive symptoms and a greater incidence of depression than their peers who experienced normal childbirth. Health professionals can use the knowledge gained from these findings to evaluate women with recurrent miscarriage for stress, anxiety and depressive symptoms and develop supportive interventions.

Update of incidence and antimicrobial susceptibility trends of Escherichia coli and Klebsiella pneumoniae isolates from Chinese intra-abdominal infection patients.

BACKGROUND: To evaluate in vitro susceptibilities of aerobic and facultative Gram-negative bacterial (GNB) isolates from intra-abdominal infections (IAIs) to 12 selected antimicrobials in Chinese hospitals from 2012 to 2014. METHODS: Hospital acquired (HA) and community acquired (CA) IAIs were collected from 21 centers in 16 Chinese cities. Extended spectrum beta-lactamase (ESBL) status and antimicrobial susceptibilities were determined at a central laboratory using CLSI broth microdilution and interpretive standards. RESULTS: From all isolated strains the Enterobacteriaceae (81.1%) Escherichia coli accounted for 45.4% and Klebsiella pneumoniae for 20.1%, followed by Enterobacter cloacae (5.2%), Proteus mirabilis (2.1%), Citrobacter freundii (1.8%), Enterobacter aerogenes (1.8%), Klebsiella oxytoca (1.4%), Morganella morganii (1.2%), Serratia marcescens (0.7%), Citrobacter koseri (0.3%), Proteus vulgaris (0.3%) and others (1.0%). Non- Enterobacteriaceae (18.9%) included Pseudomonas aeruginosa (9.8%), Acinetobacter baumannii (6.7%), Stenotrophomonas maltophilia (0.9%), Aeromonas hydrophila (0.4%) and others (1.1%). ESBL-screen positive Escherichia coli isolates (ESBL+) showed a decreasing trend from 67.5% in 2012 to 58.9% in 2014 of all Escherichia coli isolates and the percentage of ESBL+ Klebsiella pneumoniae isolates also decreased from 2012 through 2014 (40.4% to 26.6%), which was due to reduced percentages of ESBL+ isolates in HA IAIs for both bacteria. The overall susceptibilities of all 5160 IAI isolates were 87.53% to amikacin (AMK), 78.12% to piperacillin-tazobactam (TZP) 81.41% to imipenem (IMP) and 73.12% to ertapenem (ETP). The susceptibility of ESBL-screen positive Escherichia coli strains was 96.77%-98.8% to IPM, 91.26%-93.16% to ETP, 89.48%-92.75% to AMK and 84.86%-89.34% to TZP, while ESBL-screen positive Klebsiella pneumoniae strains were 70.56%-80.15% susceptible to ETP, 80.0%-87.5% to IPM, 83.82%-87.06% to AMK and 63.53%-68.38% to TZP within the three year study. Susceptibilities to all cephalosporins and fluoroquinolones were less than 50% beside 66.5% and 56.07% to cefoxitin (FOX) for ESBL+ Escherichia coli and Klebsiella pneumoniae strains respectively. CONCLUSIONS: The total ESBL+ rates decreased in Escherichia coli and Klebsiella pneumoniae IAI isolates due to fewer prevalence in HA infections. IPM, ETP and AMK were the most effective antimicrobials against ESBL+ Escherichia coli and Klebsiella pneumoniae IAI isolates in 2012-2014 and a change of fluoroquinolone regimens for Chinese IAIs is recommended.

Caspase-12 is involved in stretch-induced apoptosis mediated endoplasmic reticulum stress.

It is well recognized that mandibular growth, which is caused by a variety of functional appliances, is considered to be the result of both neuromuscular and skeletal adaptations. Accumulating evidence has demonstrated that apoptosis plays an important role in the adaptation of skeletal muscle function. However, the underlying mechanism of apoptosis that is induced by stretch continues to be incompletely understood. Endoplasmic reticulum stress (ERS), a newly defined signaling pathway, initiates apoptosis. This study seeks to determine if caspase-12 is involved in stretch-induced apoptosis mediated endoplasmic reticulum stress in myoblast and its underlying mechanism. Apoptosis was assessed by Hochest staining, DAPI staining and annexin V binding and PI staining. ER chaperones, such as GRP78, CHOP and caspase-12, were determined by reverse transcription polymerase chain reaction (RT-PCR) and Western blot. Furthermore, caspase-12 inhibitor was used to value the mechanism of the caspase-12 pathway. Apoptosis of myoblast, which is subjected to cyclic stretch, was observed in a time-dependent manner. We found that GRP78 mRNA and protein were significantly increased and CHOP and caspase-12 were activated in myoblast that was exposed to cyclic stretch. Caspase-12 inhibition reduced stretch-induced apoptosis, and caspase-12 activated caspase-3 to induce apoptosis. We concluded that caspase-12 played an important role in stretch-induced apoptosis that is associated by endoplasmic reticulum stress by activating caspase-3.

Antimicrobial Susceptibilities of Aerobic and Facultative Gram-Negative Bacilli from Intra-abdominal Infections in Patients from Seven Regions in China in 2012 and 2013.

To evaluate the antimicrobial susceptibility of Gram-negative bacilli that caused hospital-acquired and community-acquired intra-abdominal infections (IAIs) in China between 2012 and 2013, we determined the susceptibilities to 12 antimicrobials and the extended-spectrum ß-lactamase (ESBL) statuses of 3,540 IAI isolates from seven geographic areas in China in a central laboratory using CLSI broth microdilution and interpretive standards. Most infections were caused by Escherichia coli (46.3%) and Klebsiella pneumoniae (19.7%). Rates of ESBL-producing E. coli (P = 0.031), K. pneumoniae (P = 0.017), and Proteus mirabilis (P = 0.004) were higher in hospital-acquired IAIs than in community-acquired IAIs. Susceptibilities of enterobacteriaceae to ertapenem, amikacin, piperacillin-tazobactam, and imipenem were 71.3% to 100%, 81.3% to 100%, 64.7% to 100%, and 83.1% to 100%, respectively, but imipenem was ineffective against P. mirabilis (<20%). Although most ESBL-positive hospital-acquired isolates were resistant to third- and fourth-generation cephalosporins, the majority were susceptible to cefoxitin (47.9% to 83.9%). Susceptibilities of ESBL-positive isolates to ampicillin-sulbactam (<10%) were low, whereas susceptibilities to ciprofloxacin (0% to 54.6%) and levofloxacin (0% to 63.6%) varied substantially. The prevalences of cephalosporin-susceptible E. coli and K. pneumoniae were higher in the northeastern and southern regions than in the central and eastern regions, reflecting the ESBL-positive rates in these areas, and were lowest in the Jiangsu-Zhejiang (Jiang-Zhe) area where the rates of carbapenem resistance were also highest. Ertapenem, amikacin, piperacillin-tazobactam, and imipenem are the most efficacious antibiotics for treating IAIs in China, especially those caused by E. coli or K. pneumoniae. Resistance to cephalosporins and carbapenems is more common in the Jiang-Zhe area than in other regions in China.

Antifungal susceptibilities of Candida glabrata species complex, Candida krusei, Candida parapsilosis species complex and Candida tropicalis causing invasive candidiasis in China: 3 year national surveillance.

OBJECTIVES: To define the antifungal susceptibility patterns of the most common non-albicans Candida spp. in China. METHODS: We evaluated the susceptibilities to nine antifungal drugs of Candida parapsilosis species complex, Candida tropicalis, Candida glabrata species complex and Candida krusei isolates from patients with invasive candidiasis at 11 hospitals over 3 years. Isolates were identified by MALDI-TOF MS supplemented by DNA sequencing. MICs were determined by Sensititre YeastOne(TM) using current clinical breakpoints/epidemiological cut-off values to assign susceptibility (or WT), and by CLSI M44-A2 disc diffusion for fluconazole and voriconazole. RESULTS: Of 1072 isolates, 392 (36.6%) were C. parapsilosis species complex. C. tropicalis, C. glabrata species complex and C. krusei comprised 35.4%, 24.3% and 3.7% of the isolates, respectively. Over 99.3% of the isolates were of WT phenotype to amphotericin B and 5-flucytosine. Susceptibility/WT rates to azoles among C. parapsilosis species complex were ≥97.5%. However, 11.6% and 9.5% of C. tropicalis isolates were non-susceptible to fluconazole and voriconazole, respectively (7.1% were resistant to both). Approximately 14.3% of C. glabrata sensu stricto isolates (n = 258) were fluconazole resistant, and 11.6% of C. glabrata sensu stricto isolates were cross-resistant to fluconazole and voriconazole. All C. krusei isolates were susceptible/WT to voriconazole, posaconazole and itraconazole. Overall, 97.7%-100% of isolates were susceptible to caspofungin, micafungin and anidulafungin, but 2.3% of C. glabrata were non-susceptible to anidulafungin. There was no azole/echinocandin co-resistance. Disc diffusion and Sensititre YeastOne(TM) methods showed >95% categorical agreement for fluconazole and voriconazole. CONCLUSIONS: In summary, reduced azole susceptibility was seen among C. tropicalis. Resistance to echinocandins was uncommon.

[Cavernous hemangioma of mediastinum: a report of 10 cases].

OBJECTIVE: To explore the clinical characteristics, diagnosis, treatment and prognosis of cavernous hemangioma of mediastinum (CHM). METHODS: Retrospective analyses were performed for the clinical data of 10 CHM patients at our hospital along with a literature review. RESULTS: The clinical symptoms and signs were nonspecific. Although computed tomography (CT) showed mediastinal cystic mass, a definite diagnosis could not be reached. Complete surgical excision was performed with a pathological confirmation of CHM. Neither recurrence nor mortality occurred during the postoperative follow-up up to 12 years. CONCLUSIONS: CHM is rare and frequently misdiagnosed. Hypodensity or calcification inside mass on CT is diagnostic. A definite diagnosis is dependent upon typical tumor appearances and pathological report of puncture biopsy. Excision is an effective cure with a fair prognosis.

Effects of Lavender Tea on Fatigue, Depression, and Maternal-Infant Attachment in Sleep-Disturbed Postnatal Women.

BACKGROUND: Lavender inhalation aromatherapy is widely believed to impart a hypnotic effect, act as a mood stabilizer, and enhance the positive feelings of mothers toward their infants. However, research into these and other potential therapeutic effects of lavender tea has been limited. AIMS: This study was conducted in Taiwan to evaluate the effectiveness of lavender tea in relieving sleep quality, fatigue, and depression; and in improving maternal-infant attachment during the early postpartum period. METHODS: A total of 80 Taiwanese postnatal women with poor sleep quality (Postpartum Sleep Quality Scale; PSQS score ≥16) and with no history of allergy to herbal teas, foods, or medicines were assigned systematically to either the experimental group (n = 40) or the control group (n = 40). The participants in the experimental group were instructed to drink one cup of lavender tea after spending time to appreciate and smell the aroma each day for a period of 2 weeks, whereas their control group peers received regular postpartum care only. The PSQS, Edinburgh Postnatal Depression Scale, Postpartum Fatigue Scale, and Postpartum Bonding Questionnaire were used to assess outcomes. RESULTS: ANCOVA analyses using education level and pretest scores as covariates showed that experimental group participants perceived less fatigue (F = 6.281, p = .014) and depression (F = 4.731, p = .033) and showed greater bonding with their infant (F = 4.022, p = .049) compared with the control group. However, the scores for all four instruments were similar for both groups at the 4-week posttest, suggesting that the positive effects of lavender tea were limited to the immediate term. LINKING EVIDENCE TO ACTION: Healthcare researchers assume accountability for integrating research results into clinical practice. The findings in this study can gain greater attention among healthcare practitioners and encourage the correct and positive use of herbal therapy in postpartum health care.

Silencing RhoA inhibits migration and invasion through Wnt/ß-catenin pathway and growth through cell cycle regulation in human tongue cancer.

Ras homolog gene family member A (RhoA) has been identified as a critical regulator of tumor aggressive behavior. In this study, we assessed the role of RhoA in the mechanisms underlying growth, migration, and invasion of squamous cell carcinoma of tongue (TSCC). Stable RhoA knockdown of TSCC cell lines SCC-4 and CAL27 were achieved using Lentiviral transfection. The effects of RhoA depletion on cell migration, invasion, and cell proliferation were determined. The possible underlying mechanism of RhoA depletion on TSCC cell line was also evaluated by determining the expression of Galectin-3 (Gal-3), ß-catenin, and matrix metalloproteinase-9 (MMP-9) in vivo. Meanwhile, the underlying mechanism of TSCC growth was studied by analysis of cyclin D1/2, p21CIP1/WAF1, and p27Kip1 protein levels. Immunohistochemical assessments were performed to further prove the alteration of Gal-3 and ß-catenin expression. We found that, in mice injected with human TSCC cells in the tongue, RhoA levels were higher in primary tumors and metastasized lymph nodes compared with those in the normal tissues. Silencing of RhoA significantly reduced the tumor growth, decreased the levels of Gal-3, ß-catenin, MMP-9, and cyclin D1/2, and increased the levels of p21CIP1/WAF1 and p27Kip1. In vitro, RhoA knockdown also led to inhibition of cell migration, invasion, and proliferation. Our data suggest that RhoA plays a significant role in TSCC progression by regulating cell migration and invasion through Wnt/ß-catenin signaling pathway and cell proliferation through cell cycle regulation, respectively. RhoA might be a novel therapeutic target of TSCC.

Glutathione S-transferase T1 null genotype is associated with oral cancer susceptibility in Asian populations.

Though there are many studies assessing the association between glutathione S-transferase T1 (GSTT1) null genotype and oral cancer risk, the association between GSTT1 null genotype and oral cancer in Asian populations is still inconclusive. We performed a meta-analysis of 19 studies including 2,845 cases and 4,295 controls to derive a more precise estimation of the relationship. The pooled odds ratio (OR) with its corresponding 95 % confidence interval (95 % CI) was used to assess the relationship. Meta-analysis of those 19 studies suggested that there was an association between GSTT1 null genotype and elevated risk of oral cancer risk (OR = 1.25, 95 % CI = 1.00-1.56, P = 0.047). Sensitivity analysis by omitting one study at a time showed that the significance of the corresponding pooled ORs was materially altered frequently, indicating that the pooled ORs were not statistically stable. In addition, there was no obvious risk of publication bias in the meta-analysis. Therefore, the present meta-analysis suggests that the GSTT1 null genotype is a risk allele for oral cancer development in Asian populations, but more studies with large sample and well-matched controls are needed to further confirm the finding from the meta-analysis.

Human gingiva-derived mesenchymal stromal cells contribute to periodontal regeneration in beagle dogs.

Gingiva-derived mesenchymal stromal cells (GMSCs) have been considered as a promising alternative strategy for periodontal regeneration based on their potential for multilineage differentiation in vitro and the ability to form new bone in vivo. In order to investigate the capacity of GMSCs for periodontal regeneration and the fate of GMSCs during periodontal tissue repair, enhanced green fluorescent protein-labeled GMSCs were transplanted into class III furcation defects created in beagle dogs. The results showed that the transplanted GMSCs significantly enhanced the regeneration of the damaged periodontal tissue, including the alveolar bone, cementum and functional periodontal ligament (PDL). Moreover, GMSCs were able to differentiate into osteoblasts, cementoblasts and PDL fibroblasts in vivo. These findings indicate that GMSCs represent a novel cell source for periodontal tissue reconstruction.

Effect of IMB Model Combined with Spousal Support Breastfeeding Intervention on PBSES Score and Breastfeeding Rate of Primipara with Chronic Hepatitis B Virus Infection.

Objective: To analyze the effects of the info-motivation-behavior skills (IMB) model combined with spousal support breastfeeding intervention on breastfeeding Self-Efficacy Scale (PBSES) scores and breastfeeding rate of primiparas with chronic hepatitis B virus (HBV) infection. Methods: Seventy-four first-term pregnant women and 74 of their spouses were selected as the traditional control group by the convenience sampling method from July to September 2021 in obstetrics department of Shenzhen Third People's Hospital. 74 pregnant women with their first child and 74 spouses who had their first child checked during October to December 2021 were classified as the IMB model group. The traditional control group was applied with conventional intervention management mode, and the IMB model group was applied with intervention management mode based on IMB theory on the basis of the traditional control group. The self-efficacy scores of breastfeeding before and after intervention during pregnancy and during hospitalization were compared between the two groups, and the self-efficacy scores of paternal support for breastfeeding were compared. The exclusive breastfeeding rate of infants within 6 months and the maternal breastfeeding knowledge level of the two groups were compared, and the correlation between maternal breastfeeding self-efficacy score and feeding knowledge level was analyzed. Results: After pregnancy intervention, PBSES and FBSES-SF scores were significantly increased in both groups, and scores of scales in the IMB model group increased significantly than the traditional control group (all P < 0.05). The BSES-SF and FBSES-SF scores of the IMB model group increased significantly than the traditional control group at 3 days after delivery and at discharge (P < 0.05), and the scores of each scale at discharge in both groups increased significantly than those at 3 days after delivery (P < 0.05). The rate of exclusive breastfeeding in the IMB model group was 94.59% (70/74), and that in the traditional control group was 78.38% (58/74). There was a significant difference (χ2 = 8.325, P = 0.004). At discharge, the score of maternal breastfeeding knowledge increased significantly in both groups, and the score of the IMB model group increased significantly than that of the traditional control group (all P < 0.05). Pearson correlation coefficient was used to analyze the correlation between PBSES score, FBSES-SF score, and maternal feeding knowledge level, which showed positive correlation (all P < 0.05). Conclusion: The self-efficacy of prenatal breastfeeding in pregnant women with HBV is low, and the application of the IMB model combined with the intervention mode of spy-supported breastfeeding has positive effects on the improvement of maternal breastfeeding efficiency, breastfeeding health knowledge level, and postpartum breastfeeding rate, which is worthy of clinical promotion and application.

Study of the efficacy of combination therapy of SiRNAs in HepG2.2.15 cells.

BACKGROUND/AIMS: Hepatitis B virus (HBV) infection is a world-wide health problem. The major obstacles for current anti-HBV therapy are the low efficacy and the occurrence of drug resistant HBV mutations. Recent studies have demonstrated that combination therapy can enhance antiviral efficacy and overcome the shortcomings. Here, the inhibitory effect mediated by combination of small interfering RNAs (siRNAs) targeting different sites of HBV nuclear localization signal (NLS) was monitored in HepG2.2.15 cells. METHODOLOGY: Recombinant plasmid psil-HBV was constructed and transfected into HepG2.2.15 cells. At 48, 72 and 96h after transfection, culture media were collected and cells were harvested for HBV replication assay. HBsAg and HBeAg in the cell culture medium were detected by enzyme-linked immunoadsorbent assay. Intracellular viral DNA and covalently closed circular DNA (cccDNA) was quantified by real-time PCR. HBV viral mRNA was measured by reverse-transcript PCR. RESULTS: Our data demonstrated that the three used siRNAs showed marked anti-HBV effects. Combination of siRNAs, compared with individual use of each siRNA, exerted a stronger inhibition on antigen expression and viral replication, even though the final concentration of siRNA in the therapy was the same. More importantly, we showed that combination therapy significantly suppressed HBV cccDNA amplification. CONCLUSION: Our results revealed that combination of siRNAs mediated a stronger inhibition on viral replication and antigen expression in HepG2.2.15 cells, especially, the amplification of cccDNA.

Human gingiva-derived mesenchymal stem cells promote osteogenic differentiation through their immunosuppressive function.

OBJECTIVES: Human gingiva-derived mesenchymal stem cells (GMSCs) have emerged as a new MSC population exhibiting robust immune regulatory functions, multipotent differentiation potential, and regenerative ability. However, the effects of GMSCs on T cells remain unexplored. Herein, we aimed to evaluate whether GMSCs promote osteogenic differentiation by regulating immune cells. METHODS: The GMSC phenotype was confirmed using the colony-forming assay, immunophenotyping, Oil red O staining, and Alizarin red staining. mRNA expression levels of proinflammatory molecules (interleukin-1ß [IL-1ß] and tumor necrosis factor-α [TNF-α]) and anti-inflammatory factors (IL-10) were measured by quantitative reverse-transcription PCR (qRT-PCR). Then, MC3T3-E1 cells were treated with the collected co-culture supernatant, followed by alkaline phosphatase (ALP) and immunofluorescence staining to evaluate osteogenic differentiation of MC3T3-E1 cells. qRT-PCR and western blotting were employed to analyze the expression levels of osteogenic differentiation proteins, including collagen type I (COL-1), ALP, osteopontin (OPN), and runt-related transcription factor 2 (RUNX2). RESULTS: GMSCs were successfully isolated and identified. We observed that GMSCs suppressed the activated T-cell function by downregulating IL-1ß and TNF-α and upregulating IL-10. Simultaneously, the expression levels of osteogenesis-related genes (COL-1, ALP, OPN, and RUNX2) were markedly lower in the co-culture supernatant and Jurkat T cell supernatant groups than those in the normal culture medium group; however, expression levels were significantly increased in the co-culture supernatant group when compared with the Jurkat T cell supernatant group. CONCLUSION: Our findings indicate that GMSCs could promote the osteogenic differentiation of MC3T3-E1 cells by inhibiting the biological activity of activated T cells.

Post-SARS knowledge sharing and professional commitment in the nursing profession.

AIM: The aim of the present study was to examine the 2003 severe acute respiratory syndrome (SARS) crisis in relation to the degree of knowledge sharing and professional commitment, as perceived by the current nursing staff in Taiwan. BACKGROUND: The mortality rate for medical personnel during the SARS outbreak in Taiwan, which began in April 2003, was the highest among Asian countries. The SARS crisis severely challenged not only the medical skills of nurses, but also their professional commitment. DESIGN: Survey. METHODS: This study was conducted between August-December 2005, in Taiwan. Data were collected by structured questionnaire. The questionnaire was distributed by post to 8056 nurses nationwide; 2833 nurses completed and returned the questionnaire for a valid response rate of 39%. RESULTS: The results showed that knowledge sharing correlated positively with professional commitment but negatively with the impact of SARS. Professional commitment negatively correlated with SARS impact (r = -0.074, p < 0.001); however, as knowledge sharing was a controlled variable, the partial correlation between SARS impact and professional commitment was -0.039 with a p-value of 0.045, indicating virtual insignificance. That is, knowledge sharing was an antecedent variable for both SARS impact and professional commitment. CONCLUSION: This cross-sectional study provides preliminary evidence that knowledge sharing is significantly correlated with impact of SARS and professional commitment of nursing personnel. RELEVANCE TO CLINICAL PRACTICE: Hospitals and healthcare services can enhance retention of medical personnel by encouraging knowledge sharing, which enhances professional commitment and alleviates the impact of newly introduced contagious diseases.

[The coagulation factor VII gene polymorphisms in patients with myocardial infarction in Ningxia Hui and Han populations].

OBJECTIVE: To investigate the characteristics for activated coagulation factor VII(F VIIa) and the R353Q, -323 0/10 bp, HVR4 polymorphisms in the gene in patients with coronary heart disease (CHD) and myocardial infarction from Ningxia Hui and Han populations. METHODS: Four hundred and twenty angiographically proven CHD patients in the Hui population, and 508 healthy blood donors were tested for their plasma levels of coagulation factor VII using recombinant tissue factor method. The coagulation factor VII gene R353Q, -323 0/10 bp and HVR4 genotypes were identified by polymerase chain reaction. In addition, 600 Han patients with CHD and 604 healthy Han control subjects were also investigated. RESULTS: (1) The plasma F VIIa levels was significantly higher in patients with CHD and myocardial infarction than that in healthy control subjects and angor pectoris (P<0.01) in both Hui and Han populations. (2) There were significant differences in the distribution of genotypes and allelic frequencies of the R353Q between myocardial infarction and angor pectoris disease in the Hui population (P<0.05). So was the -323 0/10 bp locus in both the Hui and Han population. (3) The F VIIa level was significantly higher in individuals with RR genotype than those of Q allele carriers in the Hui population. CONCLUSION: There are polymorphisms of the F VII gene R353Q, -323 0/10 bp and HVR4 in the Hui and Han populations. The Q allele might be a protective factor against myocardial infarction in the Hui, and the plasma F VIIa level may be influenced by the R353Q polymorphism of the F VII gene. The 10 allele may be a protective factor against myocardial infarction in both the Hui and Han populations.

[Remediation Effects of Different Composite Materials on Cadmium-Contaminated Farmland Soil].

A pot experiment was conducted to study the application effects of three composite materials, namely SC (lime:organic compound fertilizer=2:3), LS (ferrous sulfate:lime=1:1) and LB (ferrous sulfate:biochar in combinations of 1:1, 1:2, 1:3, 1:4 and 1:5), on soil Cd bioavailability, Cd cumulative distribution in different wheat organs, and wheat yield. The results indicated that:① Addition of composite materials all significantly decreased the soil available Cd content by 50.2%-81.8% (SC), 29.4%-48.1% (LS), and 18.7%-42.2% (LB). Composite materials significantly increased soil pH by 1.37-2.28 (SC), 0.41-0.86 (LS), and 0.14-0.17 (LB) units. ② The Cd cumulative distribution in different wheat organs were in the order of root > leaf > stem > glume > grain. The translocation abilities of Cd in different organs were in the order of root > glume > stem and leaf. ③ Compared with the control, 0.67% SC addition and 0.67% LS addition significantly increased the wheat yields by 56.4% and 51.2%; LB addition significantly increased wheat yield by 39.6% to 51.2%. ④ The correlation analysis showed that soil pH was significantly negatively correlated with soil available Cd and Cd contents in different wheat organs. There were significant positive correlations between soil available Cd and Cd contents in different wheat organs, and the correlation coefficients were 0.711 (grain), 0.817 (glume), 0.593 (stem), 0.630 (leaf) and 0.622 (root). Meanwhile, there is also a significant positive correlation between Cd content in different wheat organs. ⑤ Comprehensively, the addition of 0.93% SC increased soil pH by a maximum of 2.28 units, and the soil available cadmium content was decreased by a maximum of 81.8%. Therefore, adding 0.93% SC was the most suitable treatment for repairing and controlling the Cd pollution in farmland soil.

[Impact of Biochar on Soil Bulk Density and Aggregates of Lou Soil].

The effect of biochar on the bulk density and aggregate stability of Lou soil was evaluated and compared after biochar was applied for 2 years and 5 years through a field-positioning experiment. Five biochar amounts were applied in this study, as follows:0 t·hm-2 (B0), 20 t·hm-2 (B20), 40 t·hm-2 (B40), 60 t·hm-2 (B60), and 80 t·hm-2 (B80). The biochar was produced by pyrolysis of stems and branches from fruit trees at the temperature of 450℃ with limited oxygen apply. At the beginning of the study, biochar was mixed thoroughly with the surface soil (0-20 cm). After 5 years, the soil bulk density and aggregate stability of 0-30 cm soil layers (0-10, 10-20, and 20-30 cm) were measured and compared with the results obtained after 2 years with the purpose of observing the long-term and persist effects of biochar application. The results showed that:① compared with the results after 2 years of application, the effect of biochar on the aggregates at depths of 0-10 cm and 10-20 cm after 5 years were less distinct, and the effect on soil aggregates at depths of 20-30 cm was significantly enhanced; ② compared with the 2 year application, the aggregate stability and the content of the>0.25 mm aggregate size fraction were significantly increased at 0-10 cm depths after 5 years of biochar application at a rate of 40 t·hm-2, while bulk density was significantly decreased; at 10-20 cm and 20-30 cm soil depths, the stability of aggregates and the content of the>0.25 mm aggregate size fraction was significantly increased, while the bulk density was significantly decreased after 5 years of biochar application at a rate of 60-80 t·hm-2;③ when the biochar application rate was 60 t·hm-2, the increase in soil organic carbon was the highest after 5 years. After biochar was applied for 5 years, its effect was more significant lower in the soil profile; the soil bulk density was significantly reduced, and aggregate stability and the content of>0.25 mm aggregates were significantly increased at depths of 20-30 cm. Based on a comprehensive evaluation of the improvement effects and economic benefits, the most suitable biochar application rate was found to be 40-60 t·hm-2. It was further concluded that the effect of biochar on soil aggregates was gradual and sustainable.

[Microbiology and management of gaseous gangrene:the Sichuan experience of 20 earthquake cases].

Wound secretion from 20 patients with gaseous gangrene was collected for Gram staining, bacterial culture and drug sensitivity tests. The results indicated that gaseous gangrene was caused by the co-infection of both aerobic and anaerobic bacteria. Gram-negative bacilli were slightly more common than other aerobic bacteria in gaseous gangrene wound, which was different from the findings of ordinary gaseous gangrene.