A systematic review and meta-analysis evaluating the role of laparoscopic surgical resection of transverse colon tumours

Objectives

A meta-analysis of published literature comparing outcomes after laparoscopic resection (LR) with open resection (OR) for transverse colon tumours.

Methods

Medline, PubMed, CINAHL, EMBASE and Cochrane were searched from inception to October 2013. The text words “minimally invasive”, “keyhole surgery” and “transverse colon” were used in combination with the medical subject headings “laparoscopy” and “colon cancer”. Outcome variables were chosen based upon whether the included articles reported results. A meta-analysis was performed to obtain a summative outcome.

Results

Six comparatives involving 444 patients were analysed. Of them 245 patients were in the LR group and 199 in the OR group. There was a significant increase in operative time in the LR group compared with the OR group [random effects model: SMD = ?0.65, 95 % CI (?1.01, ?0.30), z = ?3.60, p < 0.001] but there was significant heterogeneity amongst trials (Q = 15.51, df = 5, p = 0.008, I ² = 68). There was less blood loss in the LR group [fixed effects model: SMD = 0.70, 95 % CI (0.47, 0.93), z = 6.01, p < 0.001] and patients returned to oral diet earlier [random effects model: SMD = 0.78, 95 % CI (0.40, 1.16), z = 4.01, p < 0.001] and had a reduced time to functioning bowel [fixed effects model: SMD = 0.86, 95 % CI (0.60, 1.11), z = 6.63, p < 0.001]. No difference was seen for overall morbidity (p = 0.76) or mortality (p = 0.58).

Conclusions

LR of transverse colon tumours is a safe and effective technique. Although there is an increase in operating time, operative and clinical outcomes of intraoperative blood loss and faster recovery are seen with laparoscopic procedures.     

Double cascade dressed MOSFET from doped Eu3+and Pr3+ in a host YPO4

In this paper, we study double cascade dressed optical metal oxide semiconductor field-effect transistor (MOSFET) by exploiting enhancement and suppression for mixed-phase (hexagonal + tetragonal) of Eu³⁺:YPO₄ and different phases (hexagonal + tetragonal and pure tetragonal) of Pr³⁺:YPO₄ crystals. We report variation of fine structure energy levels in different doped ions (Eu³⁺ and Pr³⁺) in the host YPO crystal. We compared multi-level energy transition from a single dressing laser with single level energy transition from double cascade dressing lasers. Gate delay facilitates multi-energy level dressed transition and is modeled through a Hamiltonian. Based on the results of double cascade dressing, we have realized MOSFET for logic gates (inverter and logic not and gate) with a switching contrast of about 92% using a mixed phase of Pr³⁺:YPO₄.

By changing different parameters of single and double lasers, we observed the dressed energy level transition from single to multi-level with a single laser. Each sample responded based on their ions'' structure and phase symmetry in the host YPO crystal.     

Investigation on Rheological Properties of Water-Based Novel Ternary Hybrid Nanofluids Using Experimental and Taguchi Method

This study presents the rheological behavior of water-based GO-TiO₂-Ag and rGO-TiO₂-Ag ternary-hybrid nanofluids. The impact of nanoparticles’ volumetric concentration and temperature on the rheological properties were studied. All experiments were performed under temperatures ranging from 25 to 50 °C in the solid volume concentration range of 0.5–0.00005%. The data optimization technique was adopted using the Taguchi method. The types of nanomaterials, concentration, temperature, and shear rate were chosen to optimize the viscosity and shear stress. The effect of shear stress, angular sweep, frequency sweep, and damping factor ratio is plotted. The experimental results demonstrated that the rheological properties of the ternary hybrid nanofluid depend on the ternary hybrid nanofluid’s temperature. The viscosity of ternary hybrid nanofluids (THNf) change by 40% for GO-TiO₂-Ag and 33% for rGO-TiO₂-Ag when temperature and shear rates are increased. All the ternary hybrid nanofluids demonstrated non-Newtonian behavior at lower concentrations and higher shear stress, suggesting a potential influence of nanoparticle aggregation on the viscosity. The dynamic viscosity of ternary hybrid nanofluid increased with enhancing solid particles’ volume concentration and temperature.     

Chemical composition and mechanisms underlying the spasmolytic and bronchodilatory properties of the essential oil of Nepeta cataria L.

Aim of the study

The study was aimed to investigate the chemical composition and pharmacological basis for traditional use of essential oil of Nepeta cataria L. (Limiaceae) (Nc.Oil) in gastrointestinal and respiratory disorders.

Materials and methods

Chemical analysis was carried out through GC-EIMS, ¹³C NMR and Kovats Retention Indices while pharmacological study was carried out in isolated tissues preparations.

Results

Four major components; 1,8-cineol (21.00%), α-humulene (14.44%), α-pinene (10.43%) and geranyl acetate (8.21%) were identified among the 27 compounds in Nc.Oil. In isolated rabbit jejunum, Nc.Oil, papaverine and verapamil inhibited spontaneous and high K⁺(80 mM) precontractions, as well as shifted the Ca⁺⁺ concentration–response curves (CRCs) to right, indicating calcium channel blocking activity. In isolated guinea-pig trachea, Nc.Oil and papaverine inhibited carbachol (1 μM) and K⁺ precontractions with similar potency, while verapamil was more potent against K⁺. Nc.Oil also potentiated isoprenaline inhibitory CRCs, similar to papaverine, indicating papaverine-like PDE inhibitor activity. In isolated guinea-pig atria, Nc.Oil caused cardiodepression at around 25–80 times higher concentrations, similar to papaverine.

Conclusions

These data indicate that Nepeta cataria possesses spasmolytic and myorelaxant activities mediated possibly through dual inhibition of calcium channels and PDE, which may explain its traditional use in colic, diarrhea, cough and asthma.     

The role of neurotensin as a novel biomarker in the endoscopic screening of high-risk population for developing colorectal neoplasia

Colorectal cancer screening programs aim at early detection of cancer to reduce incidence rates and mortality. The objective of this study is to identify the role of neurotensin in the endoscopic screening of high-risk population for developing colorectal neoplasia. Blood samples from patients referred for urgent colonoscopy to investigate symptoms suspicious of colorectal cancer were collected. Blood neurotensin levels were measured using enzyme-linked immunosorbent assay. Colonoscopy findings were used as reference for determining the diagnostic accuracy of blood neurotensin. The study comprised 26 patients in total: 12 healthy and 14 with colon pathology (13 high-grade dysplasia adenomatous polyps, 1 adenocarcinoma). There were no statistically significant differences in the clinical and biochemical parameters between colon pathology and healthy group except neurotensin levels. Pathology in colon was associated with 3.7-fold increase in NT levels. In multivariate analysis, patients with pathology in colon have increased serum neurotensin levels compared to controls adjusted for age, gender, BMI and co-morbidities. The value of 12.93 pg/ml is associated with 87.5% sensitivity and 91.7% specificity for discriminating the colon pathology from normal colonic epithelium (p = 0.001). Neurotensin plasma values differentiate healthy people from patients suffering from colonic pathologies such as adenomatous polyps and cancer. The use of neurotensin as a potential endoscopic screening tool for identifying high-risk population for developing colorectal cancer is promising, but much has to be done before it is validated in larger scale prospective studies.     

Finite Element Analysis of the Ballistic Impact on Auxetic Sandwich Composite Human Body Armor

In this study, the ballistic impact behavior of auxetic sandwich composite human body armor was analyzed using finite element analysis. The auxetic core of the armor was composed of discrete re-entrant unit cells. The sandwich armor structure consisted of a front panel of aluminum alloy (Al 7075-T6), UHMWPE (sandwich core), and a back facet of silicon carbide (SiC) bonded together with epoxy resin. Numerical simulations were run on Explicit Dynamics/Autodyne 3-D code. Various projectile velocities with the same boundary conditions were used to predict the auxetic armor response. These results were compared with those of conventional monolithic body armor. The results showed improved indentation resistance with the auxetic armor. Deformation in auxetic armor was observed greater for each of the cases when compared to the monolithic armor, due to higher energy absorption. The elastic energy dissipation results in the lower indentation in an auxetic armor. The armor can be used safely up to 400 m/s; being used at higher velocities significantly reduced the threat level. Conversely, the conventional monolithic modal does not allow the projectile to pass through at a velocity below 300 m/s; however, the back face becomes severely damaged at 200 m/s. At a velocity of 400 m/s, the front facet of auxetic armor was destroyed; however, the back facet was completely safe, while the monolithic panel did not withstand this velocity and was completely damaged. The results are encouraging in terms of resistance offered by the newly adopted auxetic armor compared to conventional monolithic armor.     

Evaluation of multifunctional synthetic tetralone derivatives for treatment of Alzheimer's disease

Neurodegeneration, a complex disease state, comprises several pathways that contribute to cell death. Conventional approach of targeting only one of these pathways has not been proven to be entirely successful and has demanded a hypothetical change as to how researchers design and develop new drugs. In this study, effects of a series of α, β‐unsaturated carbonyl‐based tetralone derivatives against Alzheimer's disease (AD) were investigated. Moreover, their activity toward amyloid β‐induced cytotoxicity was also studied. Six compounds including 3f , 3o , 3u , 3ae , 3af , and 3ag were discovered to be most protective against Aβ‐induced neuronal cell death in PC12 cells. The findings of in vitro experiment revealed that most of these compounds exhibited potent inhibitory activity against MAO‐B, AChE, and self‐induced Aβ_1–42 aggregation. The compound 3f exhibited best AChE (IC₅₀ = 0.045 ± 0.02 μm ) inhibitory potential in addition to potent inhibition of MAO‐B (IC₅₀ = 0.88 ± 0.12 μm ). Furthermore, compound 3f disassembled the Aβ fibrils produced by self‐induced Aβ aggregation by 78.2 ± 4.8%. Collectively, these findings suggest that some compounds from this series have potential to be promising multifunctional agents for AD treatment.