[Expression and significance of neutrophil surface adhesion molecules in renal transplant recipients with cytomegalovirus infection]

OBJECTIVE

To study the expression and its diagnostic significance of neutrophil surface adhesion molecules including CD11b, CD15 and CD62L after renal transplantation in recipients with cytomegalovirus (CMV) infection.

METHODS

Blood samples were collected from 142 kidney transplant recipients, including 95 males and 47 females, who received allogeneic renal transplantation between September 2009 and January 2015 in 309th Hospital of the PLA. Healthy volunteers (22 males and 9 females) were recruited from physical examination center in 309th Hospital of the PLA from September 2009 to January 2015 as healthy control group. Renal transplant recipients were divided into high active CMV infection group, active CMV infection group and CMV negative control group according to CMV-pp65 antigen detection. Neutrophil surface adhesion molecules CD11b, CD15 and CD62L were detected by flow cytometry and their mean fluorescence intensity compared among the groups. Receiver operating characteristic (ROC) curves of CD11b, CD15 and CD62L in detecting active infection in renal transplant recipients were made.

RESULTS

The mean fluorescence intensity of CD15 in high active CMV infection group(n=17) and active CMV infection group(n=65)were 776.31±89.53 and 554.39±67.89, respectively, with significant differences compared with CMV negative control group (n=60, 334.92±44.69) and healthy control group (n=31, 310.56±39.67) (all P<0.05); the expression proportions of CD11b and CD62L in high active CMV infection group and were 42.31%±6.11% and 40.35%±6.47%, respectively, with significant differences compared with active CMV infection group(62.45%±5.67% and 65.65%±5.33%), CMV negative control group(70.74%±6.55% and 70.37%±6.71%) and healthy control group(72.52%±6.48% and 72.43%±6.51%) (all P<0.05). The optimal cut-off values of CD11b and CD62L in diagnosing active CMV infection group were 56.61% and 44.35%, respectively, with the sensitivity being both 100.00%, the specificity being 76.67% and 58.06% respectively, and the area under the curve (AUC) being 0.851 and 0.628 respectively; the optimal cut-off values of CD11b and CD62L in diagnosing high active CMV infection group were 66.57% and 69.56% respectively, with the sensitivity being 81.54% and 87.69% respectively, the specificity being 100.00% and 98.33% respectively, and the AUC being 1.000 and 0.991 respectively; the optimal cut-off values of mean fluorescence intensity of CD15 in diagnosing high active CMV infection group and active CMV infection group were 542.71 and 408.03 respectively, the sensitivity in the two groups being 100.00% and 98.46% respectively, the specificity being both 100.00%, and the AUC being 1.000 and 0.999 respectively.

CONCLUSIONS

Neutrophils CD15 expression may be up-regulated in renal transplantation recipients with CMV infection, while neutrophils CD11b and CD62L expressions are down-regulated. Such changes in CD15, CD11b and CD62L expression can be used as a basis for laboratory diagnosis of active CMV infection.

A single blue nanorod light emitting diode

We report a light emitting diode (LED) consisting of a single InGaN/GaN nanorod fabricated by a cost-effective top-down approach from a standard LED wafer. The device demonstrates high performance with a reduced quantum confined Stark effect compared with a standard planar counterpart fabricated from the same wafer, confirmed by optical and electrical characterization. Current density as high as 5414 A cm(-2) is achieved without significant damage to the device due to the high internal quantum efficiency. The efficiency droop is mainly ascribed to Auger recombination, which was studied by an ABC model. Our work provides a potential method for fabricating compact light sources for advanced photonic integrated circuits without involving expensive or time-consuming fabrication facilities.

[Effect of CD40 on Foxp3(+) Treg cell in the lung of cigarette smoke exposure mice]

OBJECTIVE

To evaluate the effect of CD40 on Foxp3(+) Treg cell in the lung of cigarette smoke exposure mice.

METHODS

According to the random number table, 20 wild type (WT) C57 BL/6 mice and 20 CD40(-/-)C57 BL/6 mice were randomly divided into two groups: WT control group, WT smoke-exposure group (24 weeks) and CD40(-/-) control group, CD40(-/-) smoke-exposure group (24 weeks) (n=10 each). Alveolar airspace enlargement was observed by HE staining. Morphological change was evaluated by mean linear intercepts (MLI). Immunohistochemical method was used to detect the quantity of Foxp3(+) cell in the lung. The mRNA expression of Foxp3 was measured by fluorescence quantitative real-time polymerase chain reaction (qRT-PCR). The protein level of Foxp3 was measured by Western blot. Interleukin (IL)-10 and IL-35 levels in the lung were tested by enzyme-linked immunosorbent assay (ELISA).

RESULTS

The MLI in CD40(-/-) smoke-exposure group was significantly lower than the WT smoke-exposure group[(30.0±1.7) vs (37.3±3.7) μm], but higher than the CD40(-/-) control group[(23.2±2.5) μm], WT smoke-exposure group was significantly higher than the WT control group[(22.2±1.7) μm](all P<0.05). The percentage of Foxp3(+) cell in the lungs of CD40(-/-) smoke-exposure group was significantly higher than the WT smoke-exposure group and CD40(-/-) control group[(16.89±0.75)% vs (9.65±0.74)% and (13.58±0.51)%], WT smoke-exposure group was significantly lower than WT control group[(12.13±0.81)%](all P<0.05). In the lungs, Foxp3 mRNA and protein expression in CD40(-/-) smoke-exposure group were increased compared to WT-smoke-exposure group and CD40(-/-) control group, WT smoke-exposure group were decreased compared to WT control group (all P<0.05). In the lungs, the level of IL-10 in CD40(-/-) smoke-exposure group was higher than the WT smoke-exposure group and CD40(-/-) control group[(231±25) vs (80±31) and (183±29) ng/L], WT smoke-exposure group was lower than the WT control group[(192±37) ng/L](all P<0.05). The level of IL-35 in CD40(-/-) smoke-exposure group was higher than the CD40(-/-) control group, WT control group and WT smoke-exposure group[(208±29) vs (118±29) , (148±36), (137±37) ng/L, all P<0.05].

CONCLUSION

Knockout the CD40 gene can promote the differentiation of Foxp3(+) Treg cell in the lung of cigarette smoke exposure mice, indicating that blocking the CD40-CD40 ligand pathway may contribute to alleviate the smoking-induced pulmonary emphysema.

[Surgical management of primary hyperthyroidism and coexistent thyroid carcinoma]

OBJECTIVE

To evaluated the results of surgical treatment for primary hyperparathyroidism coexistent with thyroid cancer.

METHODS

From March 2007 to May 2014, 27 patients suffered thyroid carcinoma coexistent with primary hyperparathyroidism with pathological and laboratory confirmation were studied retrospectively. In 8 of 27 cases thyroidectomy and parathyroidectomy were performed separately, with interval time of 3 to 26 months, and in the remaining cases both procedures were done simultaneously. During surgery quick PTH evaluation and calcium measure were routinely performed.

RESULTS

Postoperative temporary hypoparathyroidism was found in 26 of 27 cases, and postoperative permanent hypoparathyroidism developed in 4 cases that underwent separate operation. Limited movement of vocal cord was showed in 4 cases after parathyroidectomy, but it lasted no more than 2 months. No permanent paralysis of recurrent laryngeal nerve was found. No thyroid cancer or hyperparathyroidism was found with follows-up of 11 to 43 months.

CONCLUSIONS

Thyroidectomy and parathyroidectomy performed separately have higher risk to develop hypoparathyroidism than they are done simultaneously. PTH and calcium should be evaluated in patients with thyroid carcinoma whenever available.

Polycatechol nanosheet: a superior nanocarrier for highly effective chemo-photothermal synergistic therapy in vivo

The integration of phototherapy and chemotherapy in a single system holds great promise to improve the therapeutic efficacy of tumor treatment, but it remains a key challenge. In this study, we describe our recent finding that polycatechol nanosheet (PCCNS) can be facilely prepared on a large scale via chemical polymerization at 4 °C, as an effective nanocarrier for loading high-density CuS nanocrystals as a photothermal agent. The resulting CuS/PCCNS nanocomposites exhibit good biocompatibility, strong stability, and a high photothermal conversion efficiency of ∼45.7%. The subsequent loading of anticancer drug doxorubicin (Dox) creates a superior theranostic agent with pH- and heat-responsive drug release, leading to almost complete destruction of mouse cervical tumor under NIR laser irradiation. This development offers an attractive theranostic agent for in vivo chemo-photothermal synergistic therapy toward biomedical applications.

[Tumor necrosis factor-α inhibitor protects against myocardial ischemia/reperfusion injury via Notch1 mediated inhibition of oxidative/nitrative stress in traumatic mice]

OBJECTIVE

To test the effects of TNF-α inhibitor Etanercept on myocardial ischemia/reperfusion (MI/R) injury in posttraumatic mice, and explore related mechanisms.

METHODS

Traumatic mouse model was established with Noble-Collip drum. Five days after trauma, Notch1 was knocked down by intramyocardial injection of Notch1 small interfering RNAs (siRNA) or scrambled siRNA (20 μg). Seven days after trauma, mice were subjected to MI/R (30 minutes ischemia followed by reperfusion). Sham operation was similarly performed without coronary artery ligation. Ten minutes before reperfusion, mice received Etanercept (8 mg/kg, i. p.). ELISA was used to detect plasma levels of TNF-α and troponin I (cTnI) and myocardial nitrotyrosine content. Twenty-four hours after reperfusion, left ventricular ejection fraction (LVEF) was measured by echocardiography. Infarct size was determined by Evans blue/2, 3, 5-triphenyl tetrazolium chloride (TTC) double staining. Cardiac caspase-3 activity was detected using a caspase-3 kit. Myocardial TNF-α and Notch1 intracellular domains (Notch1 ICD) expressions were determined by Western blot. Chemiluminescence was used to assess myocardial superoxide anion content.

RESULTS

(1) Compared to vehicle group, Etanercept treatment significantly reduced cTnI content, infarct size and caspase-3 activity (all P<0.01), while obviously increased LVEF (P<0.01). (2) Etanercept treatment also significantly reduced plasma and myocardial TNF-α contents (P<0.01), whereas markedly increased myocardial Notch1 ICD content (P<0.05). (3) Compared to scrambled siRNA group, Notch1 deficiency significantly increased cTnI content, infarct size and caspase-3 activity (P<0.05), whereas obviously reduced LVEF (P<0.05). (4) Etanercept significantly reduced myocardial superoxide anion and nitrotyrosine content (P<0.01), which was reversed by downregulation of Notch1 (P<0.05).

CONCLUSIONS

TNF-α inhibitor Etanercept can alleviate MI/R injury after trauma by reducing myocardial oxidative/nitrative stress via activating Notch1 signaling pathway.

Clinical profile of diabetic ketoacidosis in tertiary hospitals in China: a multicentre, clinic-based study

AIMS

To evaluate the clinical profile of patients with diabetic ketoacidosis in tertiary hospitals in China.

METHODS

A retrospective study of patients hospitalized with diabetic ketoacidosis between 2010 and 2012 was carried out in 15 tertiary hospitals around China. Clinical and laboratory data were collected. Patients were classified based on clinical diagnosis and treatment history. Groups were compared for differences in vital statistics and biochemical profiles at presentation.

RESULTS

The study comprised 643 patients with diabetic ketoacidosis: 308 patients (47.9%) with Type 1 diabetes, 294 patients (45.7%) with Type 2 diabetes and 41 patients (6.4%) with atypical diabetes. Three hundred and eighty-eight diabetic ketoacidosis episodes (60.3%) were in patients with known diabetes. The most common precipitating factor was infection (40.1%), followed by unknown causes (36.9%) and non-compliance with anti-diabetes treatment (16.8%). At presentation, gastrointestinal symptoms and dehydration were more common in the Type 1 diabetes group. For new-onset diabetes, only 74.4% and 55.9% of patients were evaluated for β-cell function and autoantibodies for classification. Only 67% of patients with diabetic ketoacidosis received appropriate fluid therapy and 56% patients with severe acidosis received bicarbonate therapy. The length of hospital stay was 10.0 (7.0-14.0) days. The mortality rate was 1.7%, and was much higher in Type 2 diabetes than that in Type 1 diabetes (3.2% vs. 0.4%, P < 0.01).

CONCLUSIONS

Type 2 and Type 1 diabetes contribute to a similar proportion of cases presenting with diabetic ketoacidosis in China. Admissions with diabetic ketoacidosis are still associated with significant mortality and prolonged hospitalization. The efficiency of diabetic ketoacidosis management needs to be improved by implementing the updated guidelines.

Multiplex Quantitative PCR Assays for the Detection and Quantification of the Six Major Non-O157 Escherichia coli Serogroups in Cattle Feces

Shiga toxin-producing Escherichia coli (STEC) serogroups O26, O45, O103, O111, O121, and O145, called non-O157 STEC, are important foodborne pathogens. Cattle, a major reservoir, harbor the organisms in the hindgut and shed them in the feces. Although limited data exist on fecal shedding, concentrations of non-O157 STEC in feces have not been reported. The objectives of our study were (i) to develop and validate two multiplex quantitative PCR (mqPCR) assays, targeting O-antigen genes of O26, O103, and O111 (mqPCR-1) and O45, O121, and O145 (mqPCR-2); (ii) to utilize the two assays, together with a previously developed four-plex qPCR assay (mqPCR-3) targeting the O157 antigen and three virulence genes (stx1, stx2, and eae), to quantify seven serogroups and three virulence genes in cattle feces; and (iii) to compare the three mqPCR assays to a 10-plex conventional PCR (cPCR) targeting seven serogroups and three virulence genes and culture methods to detect seven E. coli serogroups in cattle feces. The two mqPCR assays (1 and 2) were shown to be specific to the target genes, and the detection limits were 4 and 2 log CFU/g of pure culture-spiked fecal samples, before and after enrichment, respectively. A total of 576 fecal samples collected from a feedlot were enriched in E. coli broth and were subjected to quantification (before enrichment) and detection (after enrichment). Of the 576 fecal samples subjected, before enrichment, to three mqPCR assays for quantification, 175 (30.4%) were quantifiable (≥4 log CFU/g) for at least one of the seven serogroups, with O157 being the most common serogroup. The three mqPCR assays detected higher proportions of postenriched fecal samples (P > 0.01) as positive for one or more serogroups compared with cPCR and culture methods. This is the first study to assess the applicability of qPCR assays to detect and quantify six non-O157 serogroups in cattle feces and to generate data on fecal concentration of the six serogroups.

[Retrospective study about periodontal ligament healing of replanted permanent teeth in children]

OBJECTIVE

To analyze the prognosis about periodontal ligament healing of replanted permanent teeth in children and to examine the associated factors.

METHODS

The sample consisted of 49 children with 61 avulsed permanent teeth, whose injuries had been managed in the period from 2000 to 2012. The clinical data of replanted teeth were collected, and the follow-up period was no less than 12 months. The factors were analyzed in relation to postoperative outcomes, classified as functional periodontal healing (FH), infection-related (inflammatory) resorption (IRR) and replacement resorption (RR).

RESULTS

The functional healing rate was 23.0%, while replacement resorption rate was 72.1%. The replacement resorption (ankylosis) was usually observed earlier by clinical examination than by radiographic examination. 86.0% (40/47) resorptive processes were diagnosed within the first year. Physiological storages, such as milk, saline and saliva were significantly better to periodontal ligament healing than nonphysiological storages, such as tap water and sterilizing solutions (chloramine and alcohol). Functional healing was found significantly more frequent in canines and premolars.

CONCLUSION

The factor significantly affecting periodontal ligament healing is storage medium. Replacement resorption is the most common type of root resorption. The replacement resorption diagnosis must combine the radiographic examination with the clinical examination. It is better to follow up more than 1 year after tooth replantation.

KNOCKDOWN OF CASEIN KINASE 1e INHIBITS CELL PROLIFERATION AND INVASION OF COLORECTAL CANCER CELLS VIA INHIBITION OF THE Wnt/β-CATENIN SIGNALING

Deregulation of casein kinase 1 epsilon (CK1ε) is involved in the development of multiple pathological disorders such as cancer, however the function and molecular mechanism of CK1εin cancer are still unclear. In the present study, we aimed to investigate the role of CK1ε in human colorectal cancer (CRC). The expression of CK1ε was examined by immunohistochemical assay using a tissue microarray procedure. A loss-of-function experiment was performed to observe the effects of lentivirus-mediated CK1ε shRNA (Lv-shCK1ε) on cell proliferation and invasive potential by MTT and Transwell assays in CRC cell line (SW480). As a result, we found that the expression of CK1ε protein was significantly increased in CRC tissues compared with that in adjacent non-cancerous tissues (ANCT) (68.9% vs 42.2%, P=0.017) and was correlated with the Duke’s staging and depth of invasion in CRC patients (P=0.012; P=0.015). Knockdown of CK1ε reduced cell proliferation and invasion of CRC cells followed by the downregulation of wnt3α, β-catenin, PCNA and MMP-9. In conclusion, our findings show that high expression of CK1ε is positively associated with the Duke’s staging and depth of invasion in CRC patients, and knockdown of CK1ε suppresses the growth and invasion of CRC cells through inhibition of the wnt/β-catenin signaling, suggesting that CK1ε may serve as a promising therapeutic target for the treatment of CRC.

Two case reports of Castleman disease with pulmonary involvement

Castleman disease (CD) is a rare reactive lymphoproliferative disorder, first identified in 1954. We recently had the opportunity to analyse the characteristics of two variations of CD with pulmonary involvement. Case 1 had localised retroperitoneal hyaline vascular type CD, while Case 2 was diagnosed as multicentric plasma cell type CD. Both patients had pulmonary symptoms and signs, including cough, dyspnoea, hypoxaemia and ventilatory dysfunction; however, they had different physiological manifestations of their pulmonary abnormalities.

Biodegradable poly-lactic acid based-composite reinforced unidirectionally with high-strength magnesium alloy wires

Biodegradable poly-lactic acid (PLA)--based composites reinforced unidirectionally with high-strength magnesium alloy wires (MAWs) are fabricated by a heat-compressing process and the mechanical properties and degradation behavior are studied experimentally and theoretically. The composites possess improved strengthening and toughening properties. The bending strength and impact strength of the composites with 40 vol% MAWs are 190 MPa and 150 kJ/m(2), respectively, although PLA has a low viscosity and an average molecular weight of 60,000 g/mol. The mechanical properties of the composites can be further improved by internal structure modification and interface strengthening and a numerical model incorporating the equivalent section method (ESM) is proposed for the bending strength. Micro arc oxidization (MAO) of the MAWs is an effective interfacial strengthening method. The composites exhibit high strength retention during degradation and the PLA in the composite shows a smaller degradation rate than pure PLA. The novel biodegradable composites have large potential in bone fracture fixation under load-bearing conditions.

Large mesoporous carbons decorated with silver and gold nanoparticles by a self-assembly method: enhanced electrocatalytic activity for H2O2 electroreduction and sodium nitrite electrooxidation

The silver, gold nanoparticles were grown onto poly (diallyldimethyl ammoniumchloride, PDDA)-functionalized large mesoporous carbon (LMC) by simple self-assembly method. AuNPs or AgNPs/PDDA–LMC show superior electrocatalytic activity.

[Correlation between body composition and exercise capacity in patients with coronary heart disease]

OBJECTIVE

To provide the evidence for more accurately assessing the patient's body composition, predicting exercise capacity and guiding rehabilitation exercise by analyzing the body compositions in patients with coronary heart disease, and to study the correlation between body compositions and exercise capacity.

METHODS

The study enrolled 663 patients with coronary heart disease in NYHA I-II stages, who underwent coronary intervention therapy between December 2013 and August 2014. Between 15th and 20th days of the onset, cardiopulmonary exercising testing (CPET, Bruce Protocol) was conducted, and the body composition was measured with the Inboby720 body composition analyzer before CPET.

RESULTS

All the patients completed the body composition evaluation and the CPET. According to the three indicators of body mass index (BMI), percentage of body fat (PBF), waist-hip ratio (WHR), the diagnostic rate of obesity was 22.8%, 63.3%, and 72.7%, respectively. There was a good negative correlation between PBF and exercise capacity (r=-0.306, P<0.001). Compared with non-obesity patients, the exercise capacity of obesity group decreased according to PBF (P<0.01). The patients were divided into low, moderate and high exercise capacity groups according to METs, and the difference was only the PBF among the three groups (P<0.05).

CONCLUSION

PBF, measured by body composition, is a more accurate diagnosis of obesity and has a good negative correlation with exercise capacity, which can be used as an important indicator to predict the exercise capacity in patients with coronary heart disease and guide the rehabilitation exercise.

Room temperature plasmonic lasing in a continuous wave operation mode from an InGaN/GaN single nanorod with a low threshold

It is crucial to fabricate nano photonic devices such as nanolasers in order to meet the requirements for the integration of photonic and electronic circuits on the nanometre scale. The great difficulty is to break down a bottleneck as a result of the diffraction limit of light. Nanolasers on a subwavelength scale could potentially be fabricated based on the principle of surface plasmon amplification by stimulated emission of radiation (SPASER). However, a number of technological challenges will have to be overcome in order to achieve a SPASER with a low threshold, allowing for a continuous wave (cw) operation at room temperature. We report a nano-SPASER with a record low threshold at room temperature, optically pumped by using a cw diode laser. Our nano-SPASER consists of a single InGaN/GaN nanorod on a thin SiO₂ spacer layer on a silver film. The nanorod containing InGaN/GaN multi-quantum-wells is fabricated by means of a cost-effective post-growth fabrication approach. The geometry of the nanorod/dielectric spacer/plasmonic metal composite allows us to have accurate control of the surface plasmon coupling, offering an opportunity to determine the optimal thickness of the dielectric spacer. This approach will open up a route for further fabrication of electrically injected plasmonic lasers.

Inhibition enhancer of zeste homologue 2 promotes senescence and apoptosis induced by doxorubicin in p53 mutant gastric cancer cells

OBJECTIVES

Enhancer of zeste homologue 2 (EZH2) is crucially involved in epigenetic silencing by acting as a histone methyltransferase. Although EZH2 is overexpressed in many cancers and is involved in malignant cell proliferation and invasion, the role of EZH2 in senescence induced by DNA damage has up to now remained largely unknown. In this study, we sought to explore the outcome of EZH2 depletion along with exposure of doxorubicin (DOX), and related mechanisms, in gastric cancer cells.

MATERIALS AND METHODS

Here, senescence induced by DNA damage was achieved in gastric cancer cells by DOX treatment. EZH2 was downregulated by transfection with siRNA or treated with (-)-epigallocatechin-3-gallate, a targeted inhibitor. Senescence-associated β galactosidase (SA-β-gal) and formation of senescence-associated heterochromatin foci were used to identify cell senescence. To investigate effects of EZH2 depletion on the cell cycle, apoptosis and proliferation, flow cytometry and MTT analysis were employed. Changes in p53-p21 axis activation were detected by Western blotting.

RESULTS

We found that cell proliferative arrest caused by DOX could be promoted by EZH2 depletion. Mechanistically, EZH2 depletion not only worked in coordination with DNA damage during the progression of cell senescence but also promoted apoptosis in p53 mutant cells. However, it had no cooperative relationship with DOX in p53 wild-type cells.

CONCLUSIONS

These data help unravel a crucial role for EZH2 in senescence and apoptosis in gastric cancer cells and that p53 genomic status was associated with different cell responses to EZH2 silencing.

Submental cutaneous sinus tract of mandibular second molar origin

AIM

To report a case in which a submental cutaneous sinus tract resulted from apical periodontitis associated with a mandibular second molar.

SUMMARY

A 53-year-old man presented with a chronic cutaneous sinus tract in the submental region, which had previously been misdiagnosed as a thyroglossal fistula. The origin of the sinus tract was shown by sinus tract angiography to be the left mandibular second molar (tooth 37), which had apical periodontitis. The sinus tract healed after extraction of the tooth and partial excision of the lesion from an extraoral approach. Histological examination confirmed that the tract was lined with granulation tissue and not with epithelial tissue. A submental sinus tract drainage pathway was observed. Prompt dental evaluation, especially of all mandibular teeth, should be considered when assessing cases of submental cutaneous sinus tracts.

KEY LEARNING POINTS

An odontogenic origin should be part of the differential diagnosis for orofacial skin lesions. Cutaneous sinus tracts of mandibular molar origin are complex and thus a comprehensive examination should be stressed. It is necessary to examine all mandibular teeth in cases of odontogenic submental cutaneous sinus tracts. Sinus tract angiography can be used to identify the sinus tract pathway and to confirm the associated teeth. The treatment of an odontogenic cutaneous sinus tract requires the elimination of the source of infection.

Effects of chlortetracycline and copper supplementation on antimicrobial resistance of fecal Escherichia coli from weaned pigs

Feed-grade chlortetracycline (CTC) and copper are both widely utilized in U.S. pig production. Cluster randomized experiment was conducted to evaluate the effects of CTC and copper supplementation in weaned pigs on antimicrobial resistance (AMR) among fecal Escherichia coli. Four treatment groups: control, copper, CTC, or copper plus CTC were randomly allocated to 32 pens with five pigs per pen. Fecal samples were collected weekly from three pigs per pen for six weeks. Two E. coli isolates per fecal sample were tested for phenotypic and genotypic resistance against antibiotics and copper. Data were analyzed with multilevel mixed effects logistic regression, multivariate probit analysis and discrete time survival analysis. CTC-supplementation was significantly (99% [95% CI=98-100%]) associated with increased tetracycline resistance compared to the control group (95% [95% CI=94-97%]). Copper supplementation was associated with decreased resistance to most of the antibiotics tested, including cephalosporins, over the treatment period. Overall, 91% of the E. coli isolates were multidrug resistant (MDR) (resistant to ≥3 antimicrobial classes). tetA and blaCMY-2 genes were positively associated (P<0.05) with MDR categorization, while tetB and pcoD were negatively associated with MDR. tetA and blaCMY-2 were positively associated with each other and in turn, these were negatively associated with both tetB and pcoD genes; which were also positively associated with one another. Copper minimum inhibitory concentration was not affected by copper supplementation or by pcoD gene carriage. CTC supplementation was significantly associated with increased susceptibilities of E. coli to copper (HR=7 [95% CI=2.5-19.5]) during treatment period. In conclusion, E. coli isolates from the nursery pigs exhibited high levels of antibiotic resistance, with diverse multi-resistant phenotypic profiles. The roles of copper supplementation in pig production, and pco-mediated copper resistance among E. coli in particular, need to be further explored since a strong negative association of pco with both tetA and blaCMY-2 points to opportunities for selecting a more innocuous resistance profile.

Comparing real-time and conventional PCR to culture-based methods for detecting and quantifying Escherichia coli O157 in cattle feces

Detection of Escherichia coli O157 in cattle feces has traditionally used culture-based methods; PCR-based methods have been suggested as an alternative. We aimed to determine if multiplex real-time (mq) or conventional PCR methods could reliably detect cattle naturally shedding high (≥10(4) CFU/g of feces) and low (∼10(2) CFU/g of feces) concentrations of E. coli O157. Feces were collected from pens of feedlot cattle and evaluated for E. coli O157 by culture methods. Samples were categorized as (i) high shedders, (ii) immunomagnetic separation (IMS) positive after enrichment, or (iii) culture negative. DNA was extracted pre- and postenrichment from 100 fecal samples from each category (high shedder, IMS positive, culture negative) and subjected to mqPCR and conventional PCR assays based on detecting three genes, rfbE, stx1, and stx2. In feces from cattle determined to be E. coli O157 high shedders by culture, 37% were positive by mqPCR prior to enrichment; 85% of samples were positive after enrichment. In IMS-positive samples, 4% were positive by mqPCR prior to enrichment, while 43% were positive after enrichment. In culture-negative feces, 7% were positive by mqPCR prior to enrichment, and 40% were positive after enrichment. The proportion of high shedder-positive and culture-positive (high shedder and IMS) samples were significantly different from mqPCR-positive samples before and after enrichment (P < 0.01). Similar results were observed for conventional PCR. Our data suggest that mqPCR and conventional PCR are most useful in identifying high shedder animals and may not be an appropriate substitute to culture-based methods for detection of E. coli O157 in cattle feces.

Gas-phase chemistry of Mo, Ru, W, and Os metal carbonyl complexes

Metal carbonyl complexes were used for studying the gas-phase chemical behavior of Mo, Ru, W and Os isotopes with an on-line low temperature isothermal gas chromatography apparatus. Short-lived Mo and Ru isotopes were produced by a 252Cf spontaneous fission source. Short-lived nuclides of W and Os were produced using the heavy ion reactions 19F +159Tb and 165Ho, respectively. Short-lived products were thermalized in a recoil chamber filled with a gas mixture of helium and carbon monoxide. The carbonyls formed were then transported through capillaries to an isothermal chromatography column for study of the adsorption behavior as a function of temperature. On-line isothermal chromatography (IC) experiments on Teflon (PTFE) and quartz surfaces showed that short-lived isotopes of the listed elements can form carbonyl complexes which are very volatile and interact most likely in physical sorption processes. Deduced adsorption enthalpies of Mo and Ru carbonyls were − 38 ± 2 kJ/mol and − 36 ± 2 kJ/mol, respectively. These values are in good agreement with literature data, partly obtained with different chromatographic techniques. A validation of the applied Monte Carlo model to deduce adsorption enthalpies with Mo isotopes of different half-lives proved the validity of the underlying adsorption model. The investigations using a gas-jet system coupled to a heavy ion accelerator without any preseparator clearly showed the limitations of the approach. The He and CO gas mixture, which was directly added into the chamber, will result in decomposition of CO gas and produce some aerosol particles. After the experiment of 173W and 179Os in the heavy ion experiments, the Teflon column was covered by a yellowish deposit; the adsorption enthalpy of W and Os carbonyls could therefore not be properly deduced using Monte Carlo simulations.

Rapid reuptake of granzyme B leads to emperitosis: an apoptotic cell-in-cell death of immune killer cells inside tumor cells

A cell-in-cell process refers to the invasion of one living cell into another homotypic or heterotypic cell. Different from non-apoptotic death processes of internalized cells termed entosis or cannibalism, we previously reported an apoptotic cell-in-cell death occurring during heterotypic cell-in-cell formation. In this study, we further demonstrated that the apoptotic cell-in-cell death occurred only in internalized immune killer cells expressing granzyme B (GzmB). Vacuole wrapping around the internalized cells inside the target cells was the common hallmark during the early stage of all cell-in-cell processes, which resulted in the accumulation of reactive oxygen species and subsequent mitochondrial injury of encapsulated killer or non-cytotoxic immune cells. However, internalized killer cells mediated rapid bubbling of the vacuoles with the subsequent degranulation of GzmB inside the vacuole of the target cells and underwent the reuptake of GzmB by killer cells themselves. The confinement of GzmB inside the vacuole surpassed the lysosome-mediated cell death occurring in heterotypic or homotypic entosis processes, resulting in a GzmB-triggered caspase-dependent apoptotic cell-in-cell death of internalized killer cells. On the contrary, internalized killer cells from GzmB-deficient mice underwent a typical non-apoptotic entotic cell-in-cell death similar to that of non-cytotoxic immune cells or tumor cells. Our results thus demonstrated the critical involvement of immune cells with cytotoxic property in apoptotic cell-in-cell death, which we termed as emperitosis taken from emperipolesis and apoptosis. Whereas entosis or cannibalism may serve as a feed-on mechanism to exacerbate and nourish tumor cells, emperitosis of immune killer cells inside tumor cells may serve as an in-cell danger sensation model to prevent the killing of target cells from inside, implying a unique mechanism for tumor cells to escape from immune surveillance.

Hybrid III-nitride/organic semiconductor nanostructure with high efficiency nonradiative energy transfer for white light emitters

A novel hybrid inorganic/organic semiconductor nanostructure has been developed, leading to very efficient nonradiative resonant-energy-transfer (RET) between blue emitting InGaN/GaN multiple quantum wells (MQWs) and a yellow light emitting polymer. The utilization of InGaN/GaN nanorod arrays allows for both higher optical performance of InGaN blue emission and a minimized separation between the InGaN/GaN MQWs and the emitting polymer as a color conversion medium. A significant reduction in decay lifetime of the excitons in the InGaN/GaN MQWs of the hybrid structure has been observed as a result of the nonradiative RET from the nitride emitter to the yellow polymer. A detailed calculation has demonstrated that the efficiency of the nonradiative RET is as high as 73%. The hybrid structure exhibits an extremely fast nonradiative RET with a rate of 0.76 ns(-1), approximately three times higher than the InGaN/GaN MQW nonradiative decay rate of 0.26 ns(-1). It means that the RET dominates the nonradiative processes in the nitride quantum well structure, which can further enhance the overall device performance.

Detection of Escherichia coli O104 in the feces of feedlot cattle by a multiplex PCR assay designed to target major genetic traits of the virulent hybrid strain responsible for the 2011 German outbreak

A multiplex PCR was designed to detect Escherichia coli O104:H4, a hybrid pathotype of Shiga toxigenic and enteroaggregative E. coli, in cattle feces. A total of 248 fecal samples were tested, and 20.6% were positive for serogroup O104. The O104 isolates did not carry genes characteristic of the virulent hybrid strain.

Cullin1 is a novel marker of poor prognosis and a potential therapeutic target in human breast cancer

BACKGROUND

To investigate the role of Cullin1 (Cul1) in the development of breast cancer, we examined the expression of Cul1 in breast cancer tissues and analyzed the correlation between Cul1 expression and clinicopathologic variables and patients survival.

PATIENTS AND METHODS

We evaluated the Cul1 expression by immunohistochemistry using a tissue microarray (TMA) which includes 393 breast cancer tissues. We also studied the role of Cul1 in breast cancer cell proliferation, migration and invasion by carrying out CCK8 cell proliferation assay, cell migration and invasion assay.

RESULTS

The Cul1 expression was significantly correlated with breast cancer histology grade (P = 0.000), estrogen receptor status (P = 0.001), progesterone receptor status (P = 0.001) and human epidermal growth factor receptor 2 status (P = 0.002). Furthermore, we showed a strong correlation between high Cul1 expression and worse 5-year overall and disease-specific survival rates in breast cancer patients (P = 0.026 and P = 0.015, respectively). Finally, we found that Cul1 knockdown inhibits cell proliferation, migration and invasion abilities.

CONCLUSIONS

Cul1 overexpression is significantly correlated with breast cancer progression and predicts worse survival. Cul1 regulates breast cancer cell proliferation, migration and invasion.

High intensity focused ultrasound ablation of goat liver in vivo: Pathologic changes of portal vein and the "heat-sink" effect

The purpose of this study was to evaluate pathological changes of the portal vein (PV) and the effects on main branches of the hepatic PV during HIFU (high-intensity focused ultrasound) sonication when liver tissue adjacent to the main branches of hepatic PV was ablated. Normal liver tissue at 0mm, 5mm, 10mm away from the hepatic portal vein in 50 healthy goats was ablated with magnetic resonance image-guided HIFU (MRgHIFU). MRI showed a non-perfusion region at the target area but did not show any significant changes of the PV immediately after HIFU. The histological examination 1 day after HIFU showed coagulative necrosis at the target area, revealed deep-dyed swelling collagen (CS) fibers and vessel wall fracture (VWF) in the PV adjacent to the target area; however, no CS or VWF was observed in the PV 1 week after HIFU ablation. The energy required to ablate the foci at 0mm was 21% more than that at 10mm from the PV (p<0.05); the energy needed to ablate foci 5mm away from the PV was 10% more than that at 10mm from the PV (p<0.05). We concluded that minor injury of the hepatic portal vein may occur when ablating the adjacent liver tissue, and the acoustic energy deposition is related to the distance to the portal vein.

CXCL12 G801A polymorphism contributes to cancer susceptibility: a meta-analysis

CXCL12 is an important alpha-chemokine that regulates many essential biological processes including tumor development and metastasis. The CXCL12 G801A polymorphism is associated with multiple kinds of malignant cancer, but the associations are inconsistent. To derive a more precise estimation of the relationship, we conducted a meta-analysis of 16 publications with 2,888 cases and 3,611 controls. We used the odds ratio (OR) corresponding to 95% confidence interval (CI) to estimate the strength of association. The increased risk of overall cancer was found in the homozygote comparison (AA vs. GG, OR=1.43, 95℅CI=1.07-1.91), the recessive model (AA vs. GG+GA, OR=1.26, 95℅CI=1.03-1.54), and the dominant model (GA+AA vs. GG, OR=1.35, 95℅CI=1.15-1.58). In the stratified analyses, the associations were significant in breast cancer, Asians and hospital-based controls. In conclusion, this meta-analysis suggests that the CXCL12 G801A polymorphism may be a risk factor of cancer, especially in the subgroups of breast cancer, Asians and hospital-based controls.

Molecular characteristics of the SLA-2 gene from Chinese Hebao pigs

To study the molecular characteristics of swine leukocyte antigen (SLA) class I from the Hebao pig, a rare inbreed in China, a pair of primers was designed to amplify the SLA-2 gene (SLA-2-HB) and then the molecular characteristics of the gene were analyzed by computer. After cloning, sequencing and computer analysis, four SLA-2-HB alleles were found, all of 1119 bp. Sites 3-1097 were an open reading frame encoding 364 amino acids with two sets of intra-chain disulfide bonds comprising four cysteines situated in sites 125, 188, 227 and 283. By alignment of SLA-2-HB sequences with other SLA-2 alleles in the DNA Data Bank of Japan/European Molecular Biology Laboratory/GenBank database, nine key variable amino acid sites were found in the extracellular domain of the SLA-2-HB alleles at sites 23(F), 24(I), 43(A), 44(K), 50(Q), 73(N), 95(I), 114(R) and 216(S), which could be used to differentiate other SLA-2 alleles. The amino acid identities between SLA-2-HB and other SLA-2, SLA-3 and SLA-1 alleles were 87.1-97.0%, 85.0-93.9% and 83.3- 88.6%, respectively. The phylogenetic tree of SLA-2-HB showed that it was relatively independent of the other SLA-2 genes. Furthermore, the SLA-2-HB alleles were similar to HLA-B15 and HLA-A2 functional do- mains and preserved some functional sites of HLA-A2. It was concluded that SLA-2-HB is an allele of SLA-2 and that the Hebao pig might have evolved independently in China.

Effects of octreotide on jejunal hypersensitivity triggered by Cryptosporidium parvum intestinal infection in an immunocompetent suckling rat model

BACKGROUND

Similar to other bacterial or protozoan infections, human cryptosporidiosis may trigger postinfectious irritable bowel syndrome (IBS)-like symptoms, a condition in which enhanced visceral perception of pain during intestinal distension plays a pivotal role. In an immunocompetent suckling rat model which mimicks features of postinfectious IBS, Cryptosporidium parvum infection induces long-lasting jejunal hypersensitivity to distension in association with intestinal activated mast cell accumulation. The aim of the present study was to explore in this model whether octreotide, a somatostatin agonist analog, could prevent the development of jejunal hypersensitivity and intestinal mast cell/nerve fiber accumulation.

METHODS

Five-day-old Sprague-Dawley rats were infected with C. parvum and treated 10 days later with octreotide (50 g kg(-1) day(-1), i.p.) for 7 days.

KEY RESULTS

Compared with untreated infected rats, octreotide treatment of infected rats resulted in increased weight gain [day 23 postinfection (PI)], decreased food intake (day 16 PI), and a reduction in jejunal villus alterations (day 14 PI), CD3(+) IEL (day 37 PI) and mast cell (days 37 and 50 PI) accumulations, nerve fiber densities (day 50 PI), and hypersensitivity to distension (day 120 PI). In uninfected rats, the effects of octreotide treatment were limited to higher weight gain (days 16 and 23 PI) and decreased food intake (day 23 PI) compared with uninfected-untreated rats.

CONCLUSIONS & INFERENCES

Data confirms the relevance of the present rat model to postinfectious IBS studies and prompt further investigation of somatostatin-dependent regulatory interactions in cryptosporidiosis.