Network meta-analysis comparing the clinical outcomes and safety of robotic, laparoscopic, and transanal total rectal mesenteric resection for rectal cancer / 中华胃肠外科杂志

Objective: To methodically assess the clinical effectiveness and safety of robot-assisted total rectal mesenteric resection (RTME), laparoscopic-assisted total rectal mesenteric resection (laTME), and transanal total rectal mesenteric resection (taTME). Methods: A computer search was conducted on PubMed, Embase, Cochrane Library, and Ovid databases to identify English-language reports published between January 2017 and January 2022 that compared the clinical efficacy of the three surgical procedures of RTME, laTME, and taTME. The quality of the studies was evaluated using the NOS and JADAD scales for retrospective cohort studies and randomized controlled trials, respectively. Direct meta-analysis and reticulated meta-analysis were performed using Review Manager software and R software, respectively. Results: Twenty-nine publications comprising 8,339 patients with rectal cancer were ultimately included. The direct meta-analysis indicated that the length of hospital stay was longer after RTME than after taTME, whereas according to the reticulated meta-analysis the length of hospital stay was shorter after taTME than after laTME (MD=-0.86, 95%CI: -1.70 to -0.096, P=0.036). Moreover, the incidence of anastomotic leak was lower after taTME than after RTME (OR=0.60, 95%CI: 0.39 to 0.91, P=0.018). The incidence of intestinal obstruction was also lower after taTME than after RTME (OR=0.55, 95%CI: 0.31 to 0.94, P=0.037). All of these differences were statistically significant (all P<0.05). There were no statistically significant differences between the three surgical procedures regarding the number of lymph nodes cleared, length of the inferior rectal margin, or rate of positive circumferential margins (all P>0.05). An inconsistency test using nodal analysis revealed no statistically significant differences between the results of direct and indirect comparisons of the six outcome indicators (all P>0.05). Furthermore, we detected no significant overall inconsistency between direct and indirect evidence. Conclusion: taTME has advantages over RTME and laTME, in terms of radical and surgical short-term outcomes in patients with rectal cancer.

Differentiation of Lymphoma Presenting as Retroperitoneal Mass and Retroperitoneal Fibrosis: Evaluation with Multidetector-row Computed Tomography / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Retroperitoneal fibrosis (RPF) and lymphoma presenting as retroperitoneal mass may closely resemble each other and misdiagnosis may occur. This study investigated the differential imaging features of RPF and lymphoma which presented as a retroperitoneal soft tissue using multidetector-row computed tomography (MDCT).</p><p><b>METHODS</b>The 42 consecutive patients were included in this retrospective review, including 19 RPF patients (45.2%; including 13 males and 6 females; mean age: 56.7 ± 6.2 years) and 23 patients with lymphoma (54.8%; including 14 males and 9 females; mean age: 57.4 ± 12.3 years). An array of qualitative computed tomography (CT) features of lesions in 42 consecutive patients with newly diagnosed untreated RPF and lymphoma were retrospectively analyzed. The quantitative size of the lesion at the para-aortic region and attenuation in the precontrast, arterial, and portal phases were calculated in regions of interest and compared between the patients with newly diagnosed untreated RPF and with lymphoma. Receiver operating characteristic curve analysis was used to assess the potential diagnostic value of each quantitative parameter. Inter-reader concordance was also calculated.</p><p><b>RESULTS</b>Mean ages between patients with RPF and lymphoma were not significantly different (56.7 ± 6.2 years vs. 57.4 ± 12.3 years P = 0.595). Compared to those in patients with lymphoma, homogeneous enhancement (65.2% vs. 94.7%, P = 0.027) and pelvic extension (52.2% vs. 89.5%, P = 0.017) were significantly more common while the involvement of additional nodes (78.3% vs. 5.3%, P < 0.001), suprarenal extension (60.9% vs. 15.8%, P = 0.004), and aortic displacement (43.5% vs. 5.3%, P = 0.006) were significantly less common in patients with RPF. Lesion size at the para-aorta was significantly greater in patients with lymphoma, compared with RPF patients (3.9 ± 1.2 cm vs. 1.8 ± 0.6 cm; P < 0.001). The attenuation values in three phases were not significantly different between patients with RPF and lymphoma. Inter-reader concordance for subjective features ranged from very good to excellent (range: 85.7-100.0%).</p><p><b>CONCLUSIONS</b>This study showed that MDCT can help differentiate between untreated RPF and lymphoma on the basis of qualitative CT features and lesion sizes. Differentiating RPF from lymphoma on the basis of attenuation values in the precontrast, arterial, and portal phases was difficult to accomplish.</p>

Preparation of low immunogenic porcine dermal scaffold and evaluation of its cytocompatibility / 中华烧伤杂志

<p><b>OBJECTIVE</b>To observe the changes in the structure and cytocompatibility of porcine acellular dermal matrix, which was prepared with dermal reticular layer, treated with matrix metalloproteinase 7 (MMP-7), genipin, and vacuum freeze-drying.</p><p><b>METHODS</b>Fifty-four pieces of porcine dermal reticular layer, prepared with lateral abdominal skin were obtained from healthy large Yorkshire pig with mechanical method under sanitary condition, each 10.0 mm×5.0 mm in size and 0.5 - 0.6 mm in thickness. They were divided into normal control group (A(1), without treatment, n = 6), decellularization group (B, decellularized, n = 12), decellularization + MMP-7 group (C, treated with MMP-7 after decellularization, n = 12), decellularization + MMP-7 + genipin group (D, treated with MMP-7 and genipin after decellularization, n = 12), and decellularization + MMP-7 + genipin + vacuum freeze-drying group (E, treated with MMP-7, genipin, and vacuum freeze-drying after decellularization, n = 12) according to the random number table. Meanwhile, 6 pieces of human acellular dermal matrix, with the same size and thickness as listed above, were taken as control group (A(2), without treatment) in the cytocompatibility tests. HE staining and scanning electron microscope were used to detect the cell number and the change in tissue structure in dermal scaffold in groups A(1) and B-E. Immunohistochemical staining was used to determine residual vimentin, laminin and collagen IV in groups A(1), B, and C. Cytotoxicity tests were employed to test the cytotoxicity of the leaching solutions of groups B-E. Human fibroblasts were seeded on the surface of dermal scaffold in groups A(2) and B-E. The proliferation of fibroblasts were determined on post culture day (PCD) 3, 7, and 14, and the content of IL-6 and IL-8 in the supernatant were determined on PCD 3 and 7 with enzyme-linked immunosorbent assay. Data were processed with two-way analysis of variance and LSD- t test.</p><p><b>RESULTS</b>Granular structure with hair follicle in pale yellow color was observed in group A(1). Small amount of hair, epithelial root sheath, nuclei, cell debris-like structure, vimentin, laminin, and collagen IV were observed in group B but not in group C, D, or E, which had been treated with MMP-7. The toughness of dermal scaffold was stronger in groups D, E than in groups B and C as observed in gross condition observation. The collagen fibers of dermal scaffold in groups C-E maintained their structural integrity with similar arrange as that of group A(1). The interspaces among collagen fibers in groups C-E were all increased, while those of groups C and D were similar but larger than that in group B; the interspace in group E was the largest. Groups B-E scored level 0 or 1 in the cytotoxicity test. Fibroblasts could proliferate on the surface of dermal scaffold in groups A(2) and B-E. Furthermore, with the extension of culture time, fibroblasts gradually became to be stratified to form multiple layers, and they proliferated toward the dermis. High density of fibroblasts was observed on the surface in groups D and E and in the deep layer in groups A(2) and C. On PCD 7, the contents of IL-6 [(132 ± 14), (104 ± 9), (122 ± 14), (120 ± 12), (128 ± 17) pg/mL] and IL-8 [(135 ± 18), (102 ± 17), (127 ± 18), (134 ± 23), (141 ± 24) pg/mL] in the supernatant in groups A(2) and B-E were significantly higher than those on PCD 3 [(55 ± 13), (34 ± 8), (48 ± 8), (50 ± 13), (49 ± 12) pg/mL] and [(93 ± 19), (63 ± 11), (82 ± 15), (82 ± 16), (89 ± 16) pg/mL], with F values respectively 98.869, 184.038, 125.531, 93.237, 87.265 and 15.694, 23.451, 22.801, 19.607, 18.808, P values below 0.05. The differences among groups A(2) and B-E in the levels of IL-6 and IL-8 at each time point were statistically significant (with F values respectively 2.809, 3.301 and 3.757, 3.266, P values below 0.05). The differences among groups A(2), C, D, and E in amount of IL-6 and IL-8 at each time point were not statistically significant (with t values respectively 0.058 - 1.905 and 0.034 - 1.295, P values above 0.05), but they were all higher than those in group B (with t values respectively 3.707 - 5.612 and 2.785 - 4.079, P values below 0.05).</p><p><b>CONCLUSIONS</b>The low immunogenic porcine dermal scaffold treated with MMP-7, genipin, and vacuum freeze-drying after decellularization, has good cytocompatibility. The growth of only a few fibroblasts in the dermal scaffold may be correlated with genipin, which increases tissue toughness.</p>