Experimental and clinical study of influence of high-frequency electric surgical knives on healing of abdominal incision

AIM： To study the influence of high-frequency electric surgical knives on healing of abdominal incision. METHODS： Two hundred and forty white rats were divided into 10^0, 10^2, 10^5, and 10^8 groups and rat models of abdominal operation were induced by using electric surgical knives and common lancets respectively. Then they were respectively given hypodermic injections of normal saline and 0.2 mL quantitative mixture of Escherichia coil, Staphylococcus aureus and Pseudornonas aeruginosa at a concentration of 10^2, 10^5 and 10^8. On the basis of the animal experiment, 220 patients undergoing abdominal operations （above type Ⅱ） were randomly allocated into one of following three groups： electric knife （EK, 93 cases）, electro-coagulation （EC, 55 cases） and control （72 cases）. High-frequency electric surgical knives were used to dissect abdominal tissues and electro-coagulation for hemostasis in EK group. Common lancets and electro-coagulation were applied in EC group. Common lancets and tieing silk suture were used in the controls. RESULTS： In all the groups except group 10^0, infection rate of incisional wounds made by electric surgical knives were remarkably higher than that with common lancets. Furthermore, there were significant differences in groups 10^2, 10^5, and 10^8 （P 〈 0.05）, but not in group 10^0 （P 〉 0.05） between EK and EC groups. Clinical studies showed a delayed wound healing in 16 cases （17.20%） in EK, 11 cases （16.36%） in EC and 2 cases （2.86%）in the control groups. A significant difference between EK and the control groups （χ^2= 8.57, P 〈 0.01）, and between EC and the control groups （χ^2 = 5.66, P 〈 0.05） was observed, but not between EK and EC （χ^2= 0.017, P 〉 0.05）. CONCLUSION： High-frequency electric knives may remarkably delay abdominal incision healing. Its application should be minimized so as to reduce the possibility of postoperative complications.

Significance of the preoperative neutrophil-to-lymphocyte ratio in the prognosis of patients with gastric cancer

AIM: To investigate the significance of the preoperative neutrophil-to-lymphocyte ratio(NLR) in the prognosis of patients with gastric cancer(GC). METHODS: The clinical data of 291 GC patients were analysed retrospectively; these patients were divided into two groups according to their preoperative NLR: a high-NLR group(NLR ≥ 3.5, 131 cases) and a low-NLR group(NLR < 3.5, 160 cases). The clinicopathological characteristics and five-year survival rates of the two groups were compared. The NLR and other clinicopathological factors were subjected to univariate and multivariate survival analysis to evaluate the effects of the NLR on the prognosis of GC patients. RESULTS: The lowest preoperative NLR among the 291 patients was 0.56, whereas the highest preoperative NLR was 74.5. The mean preoperative NLR was 5.99 ± 8.98. Age, tumour size, T staging, tumour-node-metastasis(TNM) staging and platelet count were significantly different between the highand low-NLR groups(P < 0.05). The five-year survival rate of the high-NLR group was 17.0%, which was significantly lower than that of the low-NLR group(43.6%; 17.0% vs 43.6%, P < 0.05). The univariate analysis results showed that the five-year survival rate was related to age, tumour size, T staging, N staging, TNM staging, carcinoembryonic antigen value and NLR(P < 0.05). Multivariate analysis results showed that the NLR was an independent risk factor that likely affected the five-year survival rate of GC patients(P = 0.003, HR = 0.626, 95%CI: 0.460-0.852). CONCLUSION: The preoperative NLR could be used as a prognostic factor for GC patients; in particular, a high NLR corresponded to poor prognosis of GC patients.

Preparation of bifunctional electrocatalyst by recycling heavy metal ions from wastewater using EDTAD-functionalized MOF as highly efficient adsorbent

The recovery and subsequent reuse of heavy metal ions from industrial wastewater are crucial for promoting sustainable development,but they also presen significant challenges.In this article,ethylenediaminetetraacetic dianhydride(EDTAD),which possesses strong metal chelating ability,is covalently attached to MIL-101-NH_(2)(Fe),resulting in a significant improvement in the removal rate of heavy metal ions in wastewater.Furthermore,the recovered waste metal ions are transformed into high-performance FeNi_(3)/NiFe_(2)O_(4)@NC dual-functional oxygen evolution reaction(OER)and oxygen reduction reaction(ORR)catalysts.Specifically,FeNi_(3)/NiFe_(2)O_(4)@NC exhibits outstanding OER performance,with only a264 mV overpotential at 10 mA·cm^(-2).Density functiona theory(DFT)calculations reveal that the synergistic effect of the FeNi_(3)/NiFe_(2)O_(4)@NC heterostructure can enhance conductivity,optimize the free energy of*to OH*during OER reaction,and promote catalytic reactivity.This work not only improves the removal rate of heavy metal ions but also obtains high-performance catalysts,while providing a new approach for the treatment and secondary utilization of heavy metal ion wastewater as well as the preparation of low-cost catalysts.

Early Triassic microbialites from the Changxing Region of Zhejiang Province,South China

Microbialites, often considered as a signal of extreme marine environment, are common in the Lower Triassic strata of South China where they flourished in the aftermath of the end-Permian mass extinction. Early Triassic microbialite facies are known to vary palaeogeographically, perhaps due to differing climates, ocean chemistry, and water depths. This paper provides the first record of a brief, but spectacular development of microbialites in the aftermath of the end-Permian mass extinction at Panjiazhuang section, Changxing Region of Zhejiang Province (eastern South China). Here, the Upper Permian Changxing Formation comprises typical shallow platform facies rich in calcareous algae and foraminifera, the development of which was terminated by the major end-Permian regression. A 3.4-m-thick microbialite began to form at the onset of the transgression in the earliest Triassic. The microbialite at Panjiazhuang section is composed of thrombolite that contains abundant calcified cyanobacteria, small gastropods, microconchid tubes and ostracods, representing a low-diversity shallow marine community in the aftermath of the end-Permian crisis. The microbialites are succeeded by thin-bedded micrites bearing thin-shelled bivalves, which record a rapid sea-level rise in the Early Triassic. Abundant populations of small pyrite framboids are observed in the upper part of the microbialites and the overlying thin-bedded micrites, suggesting that dysoxic water conditions developed at that time. The appearance of microbialites near the Permian-Triassic boundary (PTB) at Panjiazhuang section was the result of peculiar marine conditions following the end-Permian regression, whilst their disappearance was due to the increasing water depth and the development of dysoxia.