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Bacterial infections and antibiotic resistance remain significant contributors to morbidity and mortality worldwide. Despite recent advances in biomedical research, a substantial number of medical devices and implants continue to be plagued by bacterial colonisation, resulting in severe consequences, including fatalities. The development of nanostructured surfaces with mechano-bactericidal properties has emerged as a promising solution to this problem. These surfaces employ a mechanical rupturing mechanism to lyse bacterial cells, effectively halting subsequent biofilm formation on various materials and, ultimately, thwarting bacterial infections. This review delves into the prevailing research progress within the realm of nanostructured mechano-bactericidal polymeric surfaces. It also investigates the diverse fabrication methods for developing nanostructured polymeric surfaces with mechano-bactericidal properties. We then discuss the significant challenges associated with each approach and identify research gaps that warrant exploration in future studies, emphasizing the potential for polymeric implants to leverage their distinct physical, chemical, and mechanical properties over traditional materials like metals.

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The potential Aflatoxin B1 (AFB1) binding Lactobacillus fermentum (LC5/a) was used for in vivo AFB1 binding and detoxification in presence of chlorophyll (CL) in male Swiss albino mice. Mice were randomly divided into seven groups. The control groups (CL, AFB1 and LC5/a) received chlorophyll (250 µg/kg b.w), AFB1 (100 µg/kg b.w) and LC5/a (1 × 108 CFU) for 21 days. The treatment group (AFB1+LC5/a) received 100 µl of lyophilized bacterial suspension (1 × 108 CFU) 2 h before the AFB1 dosage (100µg/kg b.w). The chlorophyll mice group (CL + AFB1) was given single oral dose of CL (250 µg/kg b.w) before AFB1 dosage and last mice group received the combination of CL + LC5/a before the AFB1 dosage over a period of 21 days. Ballooning of cytoplasm and necrosis in liver was evident in histopathological examination of AFB1 mice group, while, marked improvement and nearly normal histology were seen in LC5/a and CL treated mice group. The levels of AST, ALT, GST, and SOD were increased in AFB1 mice group compared to LC5/a and CL treated mice group. Elevated levels of pro-inflammatory cytokines, TNF-α, IL-12, IL-6 (324, 506, 117.25 pg/ml) were observed in AFB1 treated mice serum compared to LC5/a and CL treated mice (249.54, 322.01 and 82.35 pg/ml). Thus, Lactobacillus fermentum LC5/a has certainly sequestered AFB1 from gastrointestinal tract besides regulating the production of pro-inflammatory cytokines.

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Thirty-four isolates of Lactobacillus spp. (LAB) from 34 curd samples were evaluated for their aflatoxin B1 (AFB1) binding and probiotic properties. Upon characterization, four LAB isolates (LC3/a, LC4/c, LC/5a, and LM13/b) were found to be effective in removing AFB1 from culture media with a capacity of above 75%. Staining reaction, biochemical tests, pattern of sugar utilization, and 16s rRNA gene sequence analysis revealed the identity of all the four isolates as L. fermentum. All of them could tolerate acidic pH, salt, and bile, which promise the use of these probiotic bacterial isolates for human applications. These isolates showed poor hydrophobicity and higher auto-aggregation properties. All L. fermentum isolates were found susceptible to gentamycin, chloramphenicol, cefoperazone, ampicillin, and resistant to ciprofloxacin and vancomycin. Results of hemolytic and DNase activity indicated their nonpathogenic nature. Though all L. fermentum isolates found inhibiting the growth of Salmonella ebony, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa, maximum inhibition was obtained with isolate LC5/a. Kinetic studies revealed that all four bacteria required a minimum of 2 h to reach stationary phase of AFB1 binding. AFB1 binding ability varied from 66 to 85.2% among these four isolates. Bile (0.4%) was significant (P ≤ 0.05) in reducing the AFB1 binding property of isolates LC3/a, LC4/c, and LM13/b, while increased AFB1 binding ability was recorded at acidic pH (2.0). AFB1 binding properties of isolate LC5/a were found least affected by acidic pH and bile. The findings of our study revealed the higher efficiency of L. fermentum isolate LC5/a in reducing the bioavailability of AFB1 in gut, and additionally, it improves the consumers' health by its various probiotic characters. These beneficial characters, L. fermentum isolates, promise them to use as probiotic formulations alone or in combinations with other beneficial probiotic-bacterial isolates.

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A single pass flow diazotization/Mizoroki-Heck protocol has been developed for the production of cinnimoyl and styryl products. The factors that govern aryl diazonium salt stability have been examined in detail leading to the development of a MeOH/DMF co-solvent system in which the diazonium salts can be generated in the presence of all other reaction components and then coupled selectively to give the desired products. Finally the key role of the reaction quench for flow reactions has been demonstrated.

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BACKGROUND: Elevations of plasma vascular endothelial growth factor (VEGF) have been noted early after colorectal resection. The duration of this increase is unknown. Because VEGF is a potent promoter of angiogenesis, which is critical to tumor growth, a sustained increase in blood VEGF levels after surgery may stimulate the growth of residual metastases early after surgery. This preliminary study aimed to determine VEGF levels during the first month after colorectal resection. METHODS: Patients from three prospective studies that had late postoperative blood samples available comprised the study population. Demographic, perioperative, pathologic, and complication data were collected. Plasma samples were obtained preoperatively for all patients: on postoperative day (POD) 1 for most patients and at varying time points thereafter during the first month after surgery and beyond. Levels of VEGF were determined via enzyme-linked immunoassay (ELISA) and compared using Wilcoxon's matched pairs test. Because the numbers of specimens beyond POD 5 were limited, samples from 7-day time blocks were bundled and averaged to permit statistical analysis. RESULTS: A total of 49 patients with cancer and 30 patients with benign indications, all of whom underwent minimally invasive colorectal resection, were assessed separately. With regard to the patients with cancer, the median preoperative plasma value was 150 pg/ml, and the peak postoperative median value for the POD 14 to 20 time block was 611.1 pg/ml. Furthermore, compared with the preoperative results, significant VEGF elevations were noted on POD 3 as well as during week 2 (POD 7-13), week 3 (POD 14-20), and week 4 (POD 21-27) (p < 0.05 for each). With regard to the benign patients, the median preoperative VEGF level was 112 pg/ml, and the peak postoperative value, 286 pg/ml, was noted during postoperative week 2. Significant elevations were noted on POD 3, and for weeks 2 and 3 as well as for POD 28 and later. Between 63% and 89% of the patients at each time point beyond POD 5 had elevated VEGF levels. CONCLUSION: This preliminary study demonstrates that after minimally invasive colorectal resection for cancer, median VEGF levels are significantly elevated on POD 3 and remain increased for as long as 4 weeks. Significant elevations in a similar pattern also were noted for the benign patients. However, the baseline and postoperative median values were lower. The clinical impact from increased blood levels of VEGF is uncertain. It is possible that the growth of residual tumor deposits may be stimulated early after surgery. These results warrant a larger study as well as endothelial cell in vitro assays to determine whether postoperative plasma stimulates proliferation and invasion.

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INTRODUCTION: Experimentally, laparotomy is associated with increased tumor growth. In humans, abdominal surgery is associated with immunosuppression and elevated plasma VEGF levels that might stimulate tumor growth early after surgery. Avoidance of these surgery-related changes and their consequences may be advantageous. Granulocyte-macrophage colony stimulating factor (GMCSF) is a non-specific immune system up-regulator that has also been associated, experimentally, with increased release of soluble VEGF Receptor 1 (sVEGFR1) which is an endogenous inhibitor of VEGF. This study's purpose was to determine the impact of perioperatively administered recombinant human GMCSF (rhu-GMCSF) on both immune function and plasma sVEGFR1 levels in colorectal cancer patients. METHODS: This randomized placebo-controlled study included 36 colorectal cancer patients who underwent minimally invasive resection (17 GMCSF, 19 Placebo). Patients received 7 subcutaneous injections of either rhu-GMCSF, 125 microg/m2, or saline on preoperative days 3, 2 and 1 and on postoperative days (POD) 1, 2, 3 and 4. A number of immune parameters were followed and plasma levels of soluble VEGF Receptor 1 (sVEGFR1) and VEGF were determined. RESULTS: The total WBC, neutrophil, eosinophil, and monocyte counts were significantly higher after surgery in the GMCSF group; no differences were noted for the other immune parameters. In the GMCSF group, median plasma sVEGFR1 levels were significantly elevated on POD 1 (188.1 pg/ml), and on POD 5 (142.8 pg/ml) when compared to pre-GMCSF levels (0 pg/ml) (p-value<0.05 for all comparisons). In the placebo group, the POD5 median sVEGFR1 level (116.3 pg/ml) was elevated and of borderline significance (p=0.05) vs the pre-treatment result (0 pg/ml). Of note, both groups had significantly elevated median plasma VEGF levels on POD 5 (Control 435.7 pg/ml; GMCSF 385.3 pg/ml) when compared to their preoperative results (Control 183.3 pg/ml, p=0.0013; GMCSF 171.5 pg/ml, p=0.0055). CONCLUSIONS: Perioperative GMCSF was not associated with an immune function benefit in this study, however, such treatment leads to increased plasma sVEGFR1 levels. Colorectal resection, with or without GMCSF, was also associated with increased VEGF levels postoperatively. Increased plasma levels of sVEGFR1 after surgery might limit the pro-angiogenic tumor stimulatory effects of VEGF. Further study of GMCSF's impact on angiogenesis appears warranted.

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OBJECTIVES: Laparoscopic renal surgery has only recently become popular in the UK and, still, only a handful of pediatric urologists are offering the laparoscopic approach to their patients; therefore, there are only limited places available for training in this discipline. In this institution, which is a major tertiary referral center for pediatric urology having four consultants, one urologist specializes in laparoscopic renal surgery and about 50 laparoscopic ablative renal surgical procedures are performed annually. The aim of this study was to determine the effectiveness of the training provided, for three trainees, in light of the complexity of the ablative procedures performed. PATIENTS AND METHODS: Patients who required laparoscopic ablative renal surgery from June 2003 to May 2004 were identified from the prospectively maintained database and data were analyzed. During this period of 12 months, 49 operations have been performed laparoscopically. There were three trainees, A, B and C, who joined the mentor, at different times, for a continuous period of 6, 12 and 6 weeks, respectively. The training was one to one and, at an appropriate level of expertise, the trainees were allowed to perform operations independently; they continued to do so after returning to their units. RESULTS: There were 22 males and 27 females, age ranging from 8 months to 16 years (mean 3.6 years). There were 25 nephrectomies, 23 via the prone retroperitoneal (PRP) approach and two via the transperitoneal (TP) approach; the mean time taken was 70 min. There were 12 nephroureterectomies, six via the PRP, three via the TP, and the other three via the lateral retroperitoneal (LRP) approach; the mean time taken was 100 min. There were 10 heminephroureterectomies (six upper pole and four lower pole), six via the PRP, three via the TP and one via the LRP approach; the mean time taken was 160 min. Of two bilateral nephrectomies one was via the PRP and one the TP approach, and the mean time taken was 170 min. The mean time to discharge for nephrectomy was 7 h, and for nephroureterectomy, heminephroureterectomy and bilateral nephrectomy 21, 23 and 43 h, respectively. Trainee A had been in pediatric surgery for 4 years and during a period of 6 weeks he assisted in five operations, but did not get the opportunity to perform independently. Trainee B had been in pediatric surgery for 13 years and during a period of 12 weeks he assisted in nine operations and performed three. Trainee C had been in pediatric surgery for 20 years and during a period of 6 weeks he assisted in five operations and performed one. Since returning to their overseas units, trainee B and trainee C have successfully performed two nephrectomies each. CONCLUSION: Retroperitoneoscopic renal surgery is within the grasp of any experienced urologist or urology trainee. With intensive exposure and one-to-one mentoring, 6-12 weeks would be sufficient to achieve adequate competence and confidence to perform a prone retroperitoneoscopic nephrectomy.

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We study trade-offs presented by local search algorithms in complex networks which are heterogeneous in edge weights and node degree. We show that search based on a network measure, local betweenness centrality (LBC), utilizes the heterogeneity of both node degrees and edge weights to perform the best in scale-free weighted networks. The search based on LBC is universal and performs well in a large class of complex networks.

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Vesnarinone, a positive inotropic drug developed for congestive heart failure, and its metabolites (OPC-8230, OPC-18136, OPC-18137) were analyzed in human dialysate and urine (plus an additional metabolite: OPC-18692 in urine) samples using a modification to a previously published LC-MS/MS assay for the analysis of human plasma and urine samples. OPC-8192, a structural analogue of vesnarinone, was used as the internal standard. The analytes of interest were extracted from human dialysate or urine by a solid phase extraction method using a pre-conditioned C-18 extraction column. The analytes were then resolved by a 7 min gradient elution on a reverse phase high performance liquid chromatographic column. Vesnarinone and metabolites were detected on a PE/Sciex API III+Biomolecular Mass analyzer in MS/MS mode using a Turbo IonSpray interface. The linear range of quantitation in dialysate was 2.00-100.00 ng/ml for vesnarinone and 0.50-25.00 ng/ml for each metabolite. In urine, the linear range was of 0.50-25.00 microg/ml for vesnarinone and 0.10-5.00 microg/ml for the metabolites. This method was used to support the analysis of urine and dialysate samples from renally impaired patients who are on vesnarinone treatment.

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In implementing effective remedial treatments at hazardous intersections, it often is necessary to identify the geometric and traffic factors that lead to accident occurrence. However, one particular problem frequently encountered in accident studies is how to distinguish virtually safe intersections with little likelihood of accident occurrence from those that have happened to have no accident due to the random process. To deal with this problem, the "excess" records of zero accident, the zero-inflated negative binomial was used to assign the probability to the accident outcome. Accident data at 104 signalized tee intersections in Singapore over a period of 9 years were employed for model development. The model indicates that uncontrolled left-turn slip road, permissive right-turn phase, existence of a horizontal curve, short sight distances, large number of signal phases, total approach volume, and left-turn volume may increase accident occurrence. On the other hand, right-turn channelization, acceleration section on the left-turn lane, median railings, and more than 5% approach gradient may reduce accident occurrence. Moreover, there is a trend of reducing accidents over the years.

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We have previously reported the in vitro cytotoxic activity of column fraction 5 (CC-5) of an ethanolic extract of Nigella sativa seeds. In this study, the effect of CC-5 was evaluated for its in vivo antitumor activity against i.p. (intraperitoneally) implanted murine P388 leukemia and s.c. (subcutaneously) implanted LL/2 (Lewis lung carcinoma) cells in BDF1 mice (C57BL/6 x DBA/2 mice). CC-5 at doses of 200 and 400 mg/kg b.w. prolonged the life span of these mice by 153% compared to DMSO-treated control mice. The antitumor activity of a 21-day treatment of CC-5 against s.c. implanted LL/2 was tested in mice using four experimental protocols as described in the methods. In protocols C and D, CC-5 at a dose of 400 mg/kg b.w. produced significant tumor inhibition rate (TIR) values of 60% (P < 0.001) and 70% (P < 0.001) respectively. Alpha-hederin, a triterpene saponin isolated from CC-5, when given i.p. for 7 days at doses of 5 and 10 mg/kg b.w. to mice with formed tumors, produced significant dose-dependent TIR values of 48% (P < 0.05) and 65% (p < 0.01) respectively on day 8 and 50% (P < 0.01) and 71% (P < 0.001), respectively, on day 15, compared to 81% (P < 0.01) on day 8 and 42% (P < 0.01) on day 15 in the cyclophosphamide (CP)-treated group. The underlying mechanism(s) of antitumor activity of alpha-hederin remain to be established.

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Photochemical studies of leaf of the herbs Justicia tranquebariensis. (Acanthaceae) carried out in the presence of phytosterols, flavonoids, Glycosides and absence of triterpenoids, alkaloids, saponins tannins have been reported in this herb for the first time.

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This paper presents a theoretical approach to determine the probability of misclassification of the multilayer perceptron (MLP) neural model, subject to weight errors. The type of applications considered are classification/recognition tasks involving binary input-output mappings. The analytical models are validated via simulation of a small illustrative example. The theoretical results, in agreement with simulation results, show that, for the example considered, Gaussian weight errors of standard deviation up to 22% of the weight value can be tolerated. The theoretical method developed here adds predictability to the fault tolerance capability of neural nets and shows that this capability is heavily dependent on the problem data.

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This paper introduces an approach to cosmetic surface flaw identification that is essentially invariant to changes in workpiece orientation and position while being efficient in the use of computer memory. Visual binary images of workpieces are characterized according to the number of pixels in progressive subskeleton iterations. Those subskeletons are constructed using a modified Zhou skeleton transform with disk shaped structuring elements. Two coding schemes are proposed to record the pixel counts of succeeding subskeletons with and without lowpass filtering. The coded pixel counts are on-line fed to a supervised neural network that is previously trained by the backpropagation method using flawed and unflawed simulation patterns. The test workpiece is then identified as flawed or unflawed by comparing its coded pixel counts to associated training patterns. Such off-line trainings using simulated patterns avoid the problems of collecting flawed samples. Since both coding schemes tremendously reduce the representative skeleton image data, significant run time in each epoch is saved in the application of neural networks. Experimental results are reported using six different shapes of workpieces to corroborate the proposed approach.