Where is the optimal plane to mobilize the anterior rectal wall in female patients undergoing total mesorectal excision?

BACKGROUND Since Heald proposed the total mesorectal excision(TME)procedure,the prognosis of patients with rectal cancer has been significantly improved.But Heald did not specifically describe the anterior surgical plane in female patients.And the surgical plane for mobilizing the anterior rectal wall during TME surgery in female patients remains controversial.AIM To investigate the anatomy of the female pelvis and identify the optimal plane for mobilizing the anterior rectal wall.METHODS We retrospectively collected surgical procedure videos and clinical data of female patients diagnosed with middle or low rectal cancer who underwent the TME procedure between January 2020 and October 2022 across six hospitals.The patients were divided into two groups based on the surgical approach used to mobilize the anterior rectal wall:The experimental group was to open the peritoneum at the lowest point of the peritonea reflection and enter the plane for mobilizing,while the control group was cut at 0.5-1 cm above the peritoneal reflection and enter another plan.Then,we compared the preoperative and postoperative information between the two groups.We also dissected and observed ten adult female pelvises to analyze the anatomic structure and compare the entry plane between the two approaches.Finally,we researched the pathological structure between the rectum and the vagina.RESULTS Finally,77 cases that met the criteria were included in our study.Our observations revealed that the experimental group underwent a smooth procedure,entering the plane amidst the mesorectal fascia and adventitia of the vagina,whereas the control group entered the plane between the vaginal adventitia and muscle layers.Compared to the control group,the experimental group showed a significant decrease in intraoperative bleeding[22.5(19.5-50)mL vs 17(5-20)mL,P=0.01],as well as a shorter duration of hospitalization[9(7-11.25)d vs 7(6-10)d,P=0.03].Through the examination of surgical videos and cadaveric studies,we discovered that Denonvilliers'fascia is absent in females.Additionally,pathological sections further revealed the absence of Denonvilliers'fascia in females,with only loose connective tissue present between the mesorectal fascia and adventitia of the vagina.CONCLUSION The plane amidst the mesorectal fascia and vaginal adventitia is the optimal surgical plane to mobilize the anterior rectal wall for female patients undergoing the TME procedure.

The clinical relevance of MBL2 gene polymorphism and sepsis

Objective:To detect the clinical relevance of mannose-binding lectin 2(MBL2) gene polymorphism and sepsis in Chinese lived in Hainan island.Methods: Blood samples from 57 patients with sepsis and 69 patients without sepsis were collected in the ICU of several large hospitals in Hainan province. Genomic DNA was extracted from whole blood and then PCR purification product was sequenced and typed by 3730 sequencing analyzer. The concentration of MBIL2 in serum was detected by ELISA.Results: We found that genotype and allele distributions in two groups were in accordance with the Hardy-Weinberg Equilibrium. The frequency of GA genotype was significantly higher than that in non-sepsis group(P=0.013). A allele frequency in sepsis group was also much higher than that in non-sepsis group(P=0.028).Logister regression analysis showed that the patients who carried A allele were more prone to get sepsis than G allele carrier(P=0.014, OR=2,550, 95%CI=1.207-5.386). The MBL2 level in serum of sepsis patients with genotype GG and GA was significantly lower than that in non-sepsis group(P<0.05). In sepsis group, the MBL2 serum level of patients with genotype GA was obviously lower than that in patients with genotype GG(P<0.05).Conclusions: The variation of rs 1800450 G→A increased the incidence of sepsis and decreased the level of MBL2 in serum.

Enhanced Mg/graphene interface adhesion using intermediate MgO layers:First-principles prediction and analysis

Graphene-reinforced Mg matrix composites suffer seriously from the weak Mg/graphene interfacial bonding.In this study,a first-principles study was performed to evaluate the feasibility of improving the Mg/graphene bonding using an in-situ formed intermediate MgO layer.The calculated interface adhesion strengths suggested a relative ordering(from high to low)of Mg(0001)/MgO(11−1)>MgO(11−1)/graphene>Mg(0001)/graphene.The enhanced Mg/MgO/graphene interface bonding can be attributed to the newly formed strong ionic and covalent interactions at the Mg/MgO and the MgO/graphene interfaces,respectively,which replace the otherwise very weak van der Waals bonding between Mg and graphene.

Association of MBL2 gene polymorphisms with sepsis in children and adult

Sepsis is a syndrome characterized by systemic inflammatory response caused by infection or toxin, with high morbidity and mortality. Different infection microflora and environment have great influence on the occurrence, development and prognosis of sepsis, but individual genetic factors also play an extremely important role. It was reported that the polymorphisms of mannose-binding lectin 2 gene were closely relevant to the occurrence and development of sepsis, but the conclusions in different studies were inconsistent. Therefore, we performed this reviews on the relevance of mannose-binding lectin 2 gene polymorphisms and sepsis.

Interface Design Strategy for GNS/AZ91 Composites with Semi-Coherent Structure

The interfacial structure plays an important role in the mechanical properties of magnesium matrix composite(MMCs)reinforced with graphene nanosheet(GNS)due to their poor wettability with the Mg matrix.An interface design strategy was proposed to form the semi-coherent interfacial structure with superior bonding strength.The lattice mismatch and interfacial bonding strength between Mg/rare earth oxide/carbon were utilized as key characteristics to evaluate the interfacial structure.Lanthanum oxide(La2O3)was selected as the intermediate candidate due to its low lattice mismatch and high interfacial bonding strength.To identify the interfacial structure of Mg/La2O3/graphene,first-principles calculations were conducted to calculate the ideal work of separation and electronic structure of the interfaces.Results demonstrated the presence of strong ionic and covalent interactions at the interface,which theoretically verified the strong interfacial bonding strength among Mg/La2O3/graphene interfaces.To experimentally validate the interface strength,MMCs with the interface structure of Mg/La2O3/GNS were developed.The formation of in-situ La2O3 led to the successful attainment of semi-coherent structures between Mg/La2O3 and La2O3/GNS,resulting in high strength and good ductility of the composite.Overall,this work proposes a new approach to interface design in MMCs with an enhancement of mechanical properties.

An FFT Based Fast Poisson Solver on Spherical Shells

We present a fast Poisson solver on spherical shells.With a special change of variable,the radial part of the Laplacian transforms to a constant coefficient differential operator.As a result,the Fast Fourier Transform can be applied to solve the Poisson equation with O(N^(3) logN)operations.Numerical examples have confirmed the accuracy and robustness of the new scheme.

A Kernel-Free Boundary Integral Method for Variable Coefficients Elliptic PDEs

This work proposes a generalized boundary integral method for variable coefficients elliptic partial differential equations(PDEs),including both boundary value and interface problems.The method is kernel-free in the sense that there is no need to know analytical expressions for kernels of the boundary and volume integrals in the solution of boundary integral equations.Evaluation of a boundary or volume integral is replaced with interpolation of a Cartesian grid based solution,which satisfies an equivalent discrete interface problem,while the interface problem is solved by a fast solver in the Cartesian grid.The computational work involved with the generalized boundary integral method is essentially linearly proportional to the number of grid nodes in the domain.This paper gives implementation details for a secondorder version of the kernel-free boundary integral method in two space dimensions and presents numerical experiments to demonstrate the efficiency and accuracy of the method for both boundary value and interface problems.The interface problems demonstrated include those with piecewise constant and large-ratio coefficients and the heterogeneous interface problem,where the elliptic PDEs on two sides of the interface are of different types.