Compression versus hand-sewn and stapled anastomosis in colorectal surgery: a systematic review and meta-analysis of randomized controlled trials

Anastomotic leaks are a feared complication of colorectal resections and novel techniques that have the potential to decrease them are still sought. This study aimed to compare the anastomotic leak rates in patients undergoing compression anastomoses versus hand-sewn or stapled anastomoses. Randomized controlled trials (RCTs) comparing outcomes of compression versus conventional (hand-sewn and stapled) colorectal anastomosis were collected from MEDLINE, Embase and the Cochrane Library. The quality of the RCTs and the potential risk of bias were assessed. Pooled odds ratios (OR) were calculated for categorical outcomes and weighted mean differences for continuous data. Ten RCTs were included, comprising 1969 patients (752 sutured, 225 stapled, and 992 compression anastomoses). Most used the biofragmentable anastomotic ring. There was no significant difference between the two groups in terms of anastomotic leak rates (OR 0.80, 95 % confidence interval (CI) 0.47, 1.37; p = 0.42), stricture (OR 0.54: 95 % CI 0.18, 1.64; p = 0.28) or mortality (OR 0.70; 95 % CI 0.39, 1.26; p = 0.24). Compression anastomosis was associated with an earlier return of bowel function: 1.02 (95 % CI 1.37, 0.66) days earlier (p < 0.001) and a shorter postoperative stay; 1.13 (95 % CI 1.52, 0.74) days shorter (p < 0.001), but significant heterogeneity among studies was observed. There was an increased risk of postoperative bowel obstruction in the compression group (OR 1.87; 95 % CI 1.07, 3.26; p = 0.03). There was no significant difference in wound-related and general complications, or length of surgery. Compression devices do not appear to provide an advantage over conventional techniques in fashioning colorectal anastomoses and are associated with an increased risk of bowel obstruction.     

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.     

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.     

Hyperproduction of heat-stable enterotoxin (STA4) of Escherichia coli and analysis of the unusual electrophoretic behavior of reduced and alkylated forms of STAs

The methanol-soluble heat-stable enterotoxin gene (estA4) of Escherichia coli (STA4) yielded 128-fold more toxin when expressed by a T7 RNA polymerase driven system than when driven by its own promoter. Analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of in vivo [35S]cysteine radiolabeled products of the cloned gene revealed an apparent molecular mass larger than that expected for a 19 amino acid polypeptide (mol. wt. 2049). Purified [125I]radiolabeled enterotoxin, STA1 (mol. wt. 1979) showed an Mr of 3800 when reduced, 2000 when reduced and carboxylated, and 14,500 when reduced and carboxyamidated. Similar changes after carboxyamidation were obtained with two different chemically synthesized STAs. These unusual electrophoretic mobilities were shown to be common to all STAs studied. Alkylation of the reduced STA species occurred only at the six cysteine residues of the toxin. Upon gel filtration the native, reduced, and reduced and alkylated forms of STAs eluted from the column in close agreement to the molecular weight expected from the known amino acid composition of the peptides.     

槟榔子中抗血小板聚集及抑制乙酰胆碱酯酶活性的有效成分（英文）

目的：研究槟榔子（Areca catechu）粗提取物中所含的抗血小板聚集及抑制乙酰胆碱酯酶活性的有效成分及其作用机制。方法：使用70%甲醇水溶液对槟榔子进行粗提取。使用生物发光血小板凝集仪在富血小板血浆中测定槟榔子粗提取物的抗血小板聚集作用,使用分光光度计在试管内测定槟榔子粗提取物对乙酰胆碱酯酶活性的抑制作用。检测槟榔子中的多种化合物以测定槟榔子中抗血小板聚集及抑制乙酰胆碱酯酶活性的有效成分。结果：槟榔子粗提取物能够抑制花生四烯酸、二磷酸腺苷、血小板活化因子、肾上腺素及钙离子载体引起的血小板聚集,尤其对二磷酸腺苷及钙离子载体引起的血小板聚集的抑制最为明显;槟榔子粗提取物能够显著抑制乙酰胆碱酯酶的活性。在所检测的槟榔子所含化合物中,只有儿茶素对肾上腺素引起的血小板聚集有显著的抑制作用,而这种抑制作用显著弱于槟榔子粗提取物,提示槟榔子中的其他成分参与了这种抑制作用;鞣酸、没食子酸、薯蓣皂苷元和异去甲槟榔次碱能够抑制乙酰胆碱酯酶的活性,其中鞣酸的抑制作用强于槟榔子粗提取物。结论：槟榔子中含有抗血小板聚集及抑制乙酰胆碱酯酶活性的有效成分,而发挥这些功效的确切成分有待进一步的研究证实。