Rapid, Label-Free Prediction of Antibiotic Resistance in Salmonella typhimurium by Surface-Enhanced Raman Spectroscopy.

The rapid identification of bacterial antibiotic susceptibility is pivotal to the rational administration of antibacterial drugs. In this study, cefotaxime (CTX)-derived resistance in Salmonella typhimurium (abbr. CTXr-S. typhimurium) during 3 months of exposure was rapidly recorded using a portable Raman spectrometer. The molecular changes that occurred in the drug-resistant strains were sensitively monitored in whole cells by label-free surface-enhanced Raman scattering (SERS). Various degrees of resistant strains could be accurately discriminated by applying multivariate statistical analyses to bacterial SERS profiles. Minimum inhibitory concentration (MIC) values showed a positive linear correlation with the relative Raman intensities of I990/I1348, and the R2 reached 0.9962. The SERS results were consistent with the data obtained by MIC assays, mutant prevention concentration (MPC) determinations, and Kirby-Bauer antibiotic susceptibility tests (K-B tests). This preliminary proof-of-concept study indicates the high potential of the SERS method to supplement the time-consuming conventional method and help alleviate the challenges of antibiotic resistance in clinical therapy.

Rapid Identification of Mixed Enteropathogenic Bacteria by Means of Au Nanoparticles@Bacteria Using Portable Raman Spectrometer.

Rapid detection of food-borne pathogens is the most critical and urgent issue among all the current food safety problems. As enhanced substrate, nanoparticles are widely used in surface enhanced Raman scattering (SERS) because of unique optical and physicochemical properties. In this study, Au nanoparticles with monodisperse and good reproducibility were synthesized by using sodium citrate reduction method. Applying Au nanoparticles sol as enhanced substrate, a portable Raman spectrometer had been applied for rapid detection of single and mixture pathogenic bacterial contamination by SERS. The results indicated that Escherichia coli, Salmonella typhimirium, Shigella flexner and Staphylococcus aureus showed specific Raman phenotypes at 600∼1700 cm-1. Generally, different bacteria could be easily and instantly recognized by its Raman phenotypes. The PC-LDA classification model was set up by combined bacterial Raman phenotypes with the multivariate statistical analysis. With the short-time inoculation, four enteropathogenic bacteria could be rapidly, precisely, sensitively and specifically identified. Furthermore, the model also had a good ability to predict the mixed contamination. This research provides the possibility of rapid detection in the food and biomedical fields.

Use of giant-sized flow-through venous flap for simultaneous reconstruction of dual or multiple major arteries in salvage therapy for complex upper limb traumatic injury.

BACKGROUND/OBJECTIVES: Salvage repair after complex upper limb traumatic injury is surgically challenging due to underlying major arterial impairment with complicating a large-sized soft tissue defect. The purpose of this study was to evaluate the effectiveness and safety of using a giant-sized (≥100 cm(2)) flow-through venous flap for reconstruction of dual or multiple forearm, metacarpal, or digital arteries after complex upper limb traumatic injury. METHODS: Seven patients were consecutively hospitalized for emergency salvage repair after complex upper limb traumatic injury between March 2012 and May 2014. The forearm and palmar artery defects were repaired using the calf great saphenous vein flap and the volar forearm venous flap, respectively. RESULTS: The flow-through venous flap ranged from 9.5 cm × 12.0 cm to 12.0 cm × 20.0 cm (mean, 158.4 cm(2)) in size. The flaps and affected limbs survived uneventfully in five patients, with one patient experiencing distal flap marginal necrosis and a second patient requiring amputation of the affected limb. Computed tomography angiography showed patent vessels in all patients. The mean total active motion of the repaired fingers was 199.5° versus 258.8° for the contralateral counterpart (77.1%). The sensory return was determined to be S2 in 2 patients, S3 in 3 patients and S3+ in 1 patient. The disability scores for the arm, shoulder, and hand ranged from 4.6-18.2 (mean, 11.3), and the mean Michigan hand outcomes questionnaire score was 7.8 ± 0.9. CONCLUSIONS: The flow-through venous flap is an effective and safe treatment alternative for salvage therapy of a ≥100-cm(2) complex upper limb traumatic injury with dual or multiple major arterial impairment. This technique allows simultaneous reconstruction of dual or multiple artery injuries and an extensive soft tissue defect. Serious surgical site infection remains a major safety concern and necessitates radical debridement in complicating cases.

Thumb reconstruction via a pedicled flap based on the superficial palmar branch of the radial artery from the wrist crease area.

BACKGROUND: The free flap based on the superficial palmar branch of the radial artery (SPBRA) has been extensively reported. A reversed pedicled flap based on the SPBRA, harvested from the wrist crease area, can be a potential candidate for the reconstruction of the soft-tissue and artery defects in the thumb. METHOD: Between January 2012 and October 2013, this flap was used in seven patients to reconstruct soft-tissue defects in the thumb. In three patients, blood circulation of the thumb was reestablished using flow-through flaps. The Michigan Hand Outcomes Questionnaire was used for patient self-evaluation. RESULTS: In one patient, the surgery was abandoned due to blood vessel variation. All the flaps and thumbs survived in the other six patients. The wounds healed primarily. All patients were followed up for a mean of 16.5 months (range, 12-26 months). At the last follow-up, the mean static two-point discrimination was 7.3 ± 0.9 mm on the affected side and 4.6 ± 0.7 on the contralateral side. The range of motion of the metacarpophalangeal joint and the interphalangeal joint were 66.8 ± 8.4° (contralateral, 85.2 ± 3.8°) and 67.0 ± 6.9° (contralateral, 80.5 ± 5.0°), respectively. Patient self-evaluations were good in five cases and fair in one case. CONCLUSION: The reverse island flap based on the SPBRA is feasible for soft-tissue defects and establishing blood circulation in the thumb. The donor site can be closed primarily, and the scar is inconspicuous in the wrist crease.

Use of a distal ulnar artery perforator-based bilobed free flap for repairing complex digital defects.

PURPOSE: To retrospectively evaluate the effectiveness and safety of using a distal ulnar artery perforator (DUAP)-based bilobed free flap (BFF) for the repair of complex digital defects in the hand. METHODS: We retrospectively studied 15 patients who sustained traumatic digital defects with complicating tendon and phalanx exposure and were hospitalized for repair using a DUAP-based BFF. Main outcome measures included patients' self-assessed physical appearance, total active motion, and 2-point discrimination. RESULTS: The flaps survived and the wounds healed with primary intention in all patients except one who experienced partial flap necrosis of the distal margin and required treatment with a second skin graft. Patients were observed for a mean of 13 months. The physical appearance and texture of the repaired fingers were assessed as good with minimal scarring. Total active motion and 2-point discrimination were 113° to 255° (contralateral, 255° to 275°) and 6 to 11 mm (contralateral, 5 to 8 mm), respectively. CONCLUSIONS: Use of the DUAP-based BFF is a feasible, effective, and safe treatment alternative for repairing complex digital defects with favorable aesthetic and sensorimotor outcomes. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Assessment of serum arginase I as a type 2 diabetes mellitus diagnosis biomarker in patients.

Previous studies have reported that levels of serum arginase I are increased in certain diseases. However, the exact association between arginase I and diabetes mellitus (DM) has yet to be determined. The aim of the present study was to investigate the correlation between arginase I activity and DM to determine whether arginase I activity may be used as a diagnostic biomarker for DM. DM was induced by a streptozotocin injection, while the arginase inhibitor, citrulline, was administered daily. Serum levels of glucose, reactive oxygen species (ROS) and arginase I activity were analyzed, and quantitative polymerase chain reaction and western blot analysis were performed to detect the mRNA and protein expression levels of arginase I, respectively. In addition, western blot analysis was used to determine the protein expression of the Tie 2 receptor. Pearson's analysis was used to determine the correlation between arginase I activity and Tie 2 expression, while concordance analysis was performed using the Cohen's test to obtain the Kappa statistic. The results demonstrated that serum arginase I activity levels in the rats with DM were significantly elevated compared with the control group, and positively correlated with the blood glucose levels. In addition, the blood glucose and ROS levels were increased significantly in the rats with DM. Arginase I mRNA and protein expression levels were significantly elevated in the diabetic rats when compared with the control group, and Tie 2 expression levels increased and were shown to correlate with arginase I activity in the diabetic rats. In addition, arginase I activity was shown to correlate with glucose intolerance and post-load glucose values. Good concordance was observed between arginase I activity and the clinical diagnosis for DM (κ=0.876; P<0.001). Therefore, the results indicated that arginase I may function as a diagnostic biomarker for DM rats model.

Long-term outcome of correction of tetralogy of Fallot in 56 adult patients.

BACKGROUND: Although most patients with tetralogy of Fallot undergo radical repair during infancy and childhood, patients that remain undiagnosed and untreated until adulthood can still be treated. This study aimed to evaluate longterm outcomes of adult patients with tetralogy of Fallot who were treated surgically, and to determine the predictors of postoperative pulmonary regurgitation. METHODS: Fifty-six adult patients underwent complete surgical repair. Forty-three patients (76.8%) required a transannular patch. Systolic, diastolic, and mean pressure in the main pulmonary artery were measured after repair. RESULTS: The early mortality rate was 3.6%. The 16-year survival rate was (84.4 ± 11.5)%. Late echocardiography revealed 41 patients with transannular patch who had pulmonary regurgitation, consisting of mild pulmonary regurgitation in 28 patients, moderate in eight, and severe regurgitation in five patients. In addition, there was right ventricular outflow tract stenosis in nine patients, moderate/severe tricuspid valve regurgitation in seven, and residual ventricular septal defect in five. Logistic regression analysis demonstrated that the mean pulmonary pressure measured just after repair predicted late pulmonary regurgitation. CONCLUSIONS: The long-term survival of surgically treated adult patients with tetralogy of Fallot is acceptable. The mean pressure >20 mmHg in the main pulmonary artery measured right after surgical repair may be a feasible reference to time the reconstruction of the pulmonary valve.

Down-regulation of eIF5A-2 prevents epithelial-mesenchymal transition in non-small-cell lung cancer cells.

BACKGROUND: Epithelial-mesenchymal transition (EMT) is believed to be the critical process in malignant tumor invasion and metastases, and has a great influence on improving the survival rate in non-small-cell lung cancer (NSCLC) patients. Recent studies suggested that eukaryotic initiation factor 5A-2 (eIF5A-2) might serve as an adverse prognostic marker of survival. We detected eIF5A-2 in NSCLC A549 cells, and found that the invasive capability correlates with the eIF5A-2 expression. METHODS: Transforming growth factor (TGF)-ß1 was used to induce EMT in A549 cells. Western blotting, immunofluorescence, wound healing assay, and transwell-matrigel invasion chambers were used to identify phenotype changes. Western blotting was also used to observe changes of the expression of eIF5A-2. We down-regulated the eIF5A-2 expression using an eIF5A-2 siRNA and identified the phenotype changes by western blotting and immunofluorescence. We tested the change of migration and invasion capabilities of A549 cells by the wound healing assay and transwell-matrigel invasion chambers. RESULTS: After stimulating with TGF-ß1, almost all A549 cells changed to the mesenchymal phenotype and acquired more migration and invasion capabilities. These cells also had higher eIF5A-2 protein expression. Down-regulation of eIF5A-2 expression with eIF5A-2 siRNA transfection could change the cells from mesenchymal to epithelial phenotype and decrease tumor cell migration and invasive capabilities significantly. CONCLUSIONS: The expression of eIF5A-2 was up-regulated following EMT phenotype changes in A549 cells, which correlated with enhanced tumor invasion and metastatic capabilities. Furthermore, in the A549 cell line, the process of EMT phenotype change could be reversed by eIF5A-2 siRNA, with a consequent weakening of both invasive and metastatic capabilities.

[Rapid detection of 6-benzylaminopurine residues in sprout beans by surface-enhanced raman spectroscopy].

New method for rapid and quantitative analysis of 6-benzylaminopurine (6-BA) residues in sprout beans was studied by using FAST-SPE and portable surface-enhanced Raman spectroscopy (SERS). With homemade sprout bean samples as blank control, 6-BA solutions extracted from inserted-treatment samples showed typical characteristic Raman peaks at 1002 cm(-1) tested by SERS, and normalized 1002 cm(-1) intensities had a good linear relationship with gradient concentrations of 6-BA insert-standard solutions. The high concentration linear range was 0.5-14 microg x mL(-1), and the low one was 0. 1-2 microg x mL(-1). The quantitative detection limit was down to 0.02 mg x kg(-1) that was below the maximum allowable residues (MAL) of 0. 2 mg kg(-1) in related National Standard. The recoveries were 82.3%-95.1% and the RSD was below 5%. This method with portable equipment and simple pre-treatment showed good reproducibility, short test time-consuming and easy operating, and thus it would provide efficient and sensitive solutions for large-scale on-site and rapid detections.

[Internal quality control of sperm concentrations in semen analysis: establishment of a method].

OBJECTIVE: To establish a method for internal quality control (IQC) of sperm concentration test in the laboratory. METHODS: We set the concentrations of frozen semen at 20 x 10(6) and 80 x 10(6) as low and high concentrations of putative IQC products, with QC-BEADSTM quality control beads (QCBs) as the control. Using the double-blind method, four technicians determined the sperm concentrations of the IQC products and QCBs by computer-assisted sperm analysis, and drew a quality control chart (Xbar chart and Sbar chart) for each product. Through a month of continuous detection, we calculated and compared the intra- and inter-batch coefficients of variation (CV%) of the quality control products of high and low concentrations. RESULTS: The intra-batch coefficients of variation of the assumed IQC products of high and low concentrations were CV3.5% and CV2.4%, and their inter-batch coefficients of variation were CV10.2% and CV9.6%. The intra-batch coefficients of variation of the QCBs of high and low concentrations were CV5.1% and CV7.1%, and their inter-batch coefficients of variation were CV7.1% and CV8%. The intra-batch coefficients of variation of both IQC products and QCBs of high and low concentrations were <10%, and their inter-batch coefficients of variation were <15%, which conformed to Levey-Jennings quality control principles and achieved IQC purposes. No significant differences were found in either intra- or inter-batch coefficients of variation between the IQC products and QCBs of high and low concentrations (P>0.05), indicating that assumed IQC products can replace QCBs for internal quality control in the laboratory. CONCLUSION: The IQC method we established for determining sperm concentration is simple, feasible and reliable.

Blockade of persistent sodium currents contributes to the riluzole-induced inhibition of spontaneous activity and oscillations in injured DRG neurons.

In addition to a fast activating and immediately inactivating inward sodium current, many types of excitable cells possess a noninactivating or slowly inactivating component: the persistent sodium current (I(NaP)). The I(NaP) is found in normal primary sensory neurons where it is mediated by tetrodotoxin-sensitive sodium channels. The dorsal root ganglion (DRG) is the gateway for ectopic impulses that originate in pathological pain signals from the periphery. However, the role of I(NaP) in DRG neurons remains unclear, particularly in neuropathic pain states. Using in vivo recordings from single medium- and large-diameter fibers isolated from the compressed DRG in Sprague-Dawley rats, we show that local application of riluzole, which blocks the I(NaP), also inhibits the spontaneous activity of A-type DRG neurons in a dose-dependent manner. Significantly, riluzole also abolished subthreshold membrane potential oscillations (SMPOs), although DRG neurons still responded to intracellular current injection with a single full-sized spike. In addition, the I(NaP) was enhanced in medium- and large-sized neurons of the compressed DRG, while bath-applied riluzole significantly inhibited the I(NaP) without affecting the transient sodium current (I(NaT)). Taken together, these results demonstrate for the first time that the I(NaP) blocker riluzole selectively inhibits I(NaP) and thereby blocks SMPOs and the ectopic spontaneous activity of injured A-type DRG neurons. This suggests that the I(NaP) of DRG neurons is a potential target for treating neuropathic pain at the peripheral level.

[The application of improved Glasgow coma scale score of 15 as switching point for invasive noninvasive mechanical ventilation in treatment of severe respiratory failure in chronic obstructive pulmonary disease].

OBJECTIVE: To estimate the feasibility and the efficacy of early extubation and the sequential non invasive mechanical ventilation (MV) in severe respiratory failure of chronic obstructive pulmonary disease (COPD) with the improved Glasgow coma scale (GCS) score of 15 as the switching point. METHODS: By a prospective control study, 20 patients with COPD and respiratory failure who had undergone endotracheal intubation and MV from March 2007 to November 2009 were enrolled as treatment group. Invasive MV with synchronous intermittent mandatory ventilation and pressure support ventilation (SIMV+PSV) pattern were given to these patients. When the period of "improved GCS score of 15 standard" window period appeared and being kept for 2 hours, endotracheal tube was extubated, and nasal mask with PSV+positive end expiratory pressure (PEEP) was used, followed by gradual decrease of the level of pressure support till weaning of MV. Nineteen patients who were treated with MV with ordinary way of weaning from March 2005 to March 2007 served as the control group. Prior to the MV, the ventilation and oxygenation index , the length of invasive MV, total MV time, total hospital stay, re intubation and ventilator associated pneumonia (VAP) occurred in the number of cases were observed and compared between two groups. RESULTS: There was no significant difference in the ventilation and oxygenation index prior to the MV. Compared with control group, in treatment group, the length of invasive ventilation (days: 3.2±1.1 vs. 10.5±3.2), the total duration of MV (days: 4.8±2.5 vs. 10.5±3.2), the length of hospital stay (days: 17±3 vs. 22±7) were significantly shorter (all P<0.01), and the incidence of VAP was significantly lower (cases: 0 vs. 5, P<0.01), while the number of re intubation was slightly higher but without statistical significance (cases: 3 vs. 1, P>0.05). CONCLUSION: The application of improved GCS score of 15 as the switching point with 2 hours as window period for early extubation and non invasive nasal mask ventilation can significantly improve the therapeutic effect in patients with severe respiratory failure in COPD.

Effects of cadium, zinc and lead on soil enzyme activities.

Heavy metal (HM) is a major hazard to the soil-plant system. This study investigated the combined effects of cadium (Cd), zinc (Zn) and lead (Pb) on activities of four enzymes in soil, including calatase, urease, invertase and alkalin phosphatase. HM content in tops of canola and four enzymes activities in soil were analyzed at two months after the metal additions to the soil. Pb was not significantly inhibitory than the other heavy metals for the four enzyme activities and was shown to have a protective role on calatase activity in the combined presence of Cd, Zn and Pb; whereas Cd significantly inhibited the four enzyme activities, and Zn only inhibited urease and calatase activities. The inhibiting effect of Cd and Zn on urease and calatase activities can be intensified significantly by the additions of Zn and Cd. There was a negative synergistic inhibitory effect of Cd and Zn on the two enzymes in the presence of Cd, Zn and Pb. The urease activity was inhibited more by the HM combinations than by the metals alone and reduced approximately 20%-40% of urease activity. The intertase and alkaline phosphatase activities significantly decreased only with the increase of Cd concentration in the soil. It was shown that urease was much more sensitive to HM than the other enzymes. There was a obvious negative correlation between the ionic impulsion of HM in soil, the ionic impulsion of HM in canola plants tops and urease activity. It is concluded that the soil urease activity may be a sensitive tool for assessing additive toxic combination effect on soil biochemical parameters.

[Changes in serum contents of inflammatory mediators after tetramethylene-disulfo-tetramine poisoning and clinical study of a new treatment regime for the poisoning].

OBJECTIVE: To study the changes in serum contents of beta-endorphin (beta-EP), endothelins (ET), nitric oxide (NO) and tumor necrosis factor (TNF) after acute tetramethylene-disulfo-tetramine (TDT) poisoning and therapeutic effect of a new treatment regime. METHODS: (1) Forty-eight patients with tetramethylene-disulfo-tetramine poisoning (experiment group) were enrolled in this study. The serum levels of beta-EP, ET, NO and TNF were measured upon hospitalization and 1, 3, 5, 7, 9, 11, 13, 15, 17 and 19 days after poisoning, respectively, and compared with those of 30 healthy individuals (control group B). (2) They were treated with the improved regime and compared with patients treated with the conventional regime designated as control group A. RESULTS: (1) In 48 patients treated with improved regime, 45 were cured and 3 died. (2) The serum levels of beta-EP, ET, NO and TNF from 45 patients who were cured were significantly higher at hospitalization compared with those of healthy individuals, with the peak values appeared on day 1 after poisoning in the mild, moderate and severe groups. Beta-EP levels returned to normal range on days 9, 13 and 17 after poisoning respectively in the mild, moderate and severe groups. ET levels returned to normal range on days 7, 13 and 15 after poisoning respectively in the mild, moderate and severe groups. NO levels returned to normal range on days 7, 11 and 11 after poisoning respectively in the mild, moderate and severe groups. TNF levels returned to normal range on days 9, 11 and 17 after poisoning respectively in the mild, moderate and severe groups. (3) The serum levels of beta-EP, ET, NO and TNF in 3 non-survivors were very high at hospitalization and continued to increase in the course of treatment. (4) The cumulative doses of diazepam and Phenobarbital, and the eclampsia time were significantly less in the experiment group than those of control group A. CONCLUSION: (1) The serum levels of beta-EP, ET, NO and TNF are correlated with the severity of tetramethylene-disulfo-tetramine poisoning and general conditions of the patients. (2) When the serum levels of beta-EP, ET, NO and TNF decrease gradually in the course of treatment, prognosis is better. On the contrary, the prognosis is poor when their levels increase gradually. (3) Measures to decrease levels of beta-EP, ET, NO and TNF result in a better prognosis of patients with tetramethylene-disulfo-tetramine poisoning. (4) The improved regime can be considered a better therapeutic strategy in tetramethylene-disulfo-tetramine poisoning.