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There are three steps to synthesize the MT vinylphenyl curable silicone resin. Step 1; MT vinylphenyl liquid silicone resin has been synthesized by trimethoxyphenyl silane (as the base material), divinyl - 1,1,3,3 - tetramethydisiloxane and hexamethyldisiloxane (as the end-capping agent) by co-hydrolysis condensation under acidic at first, and then the excess hydroxyl groups are eliminated under alkaline. Step 2: MT hydrophenyl curable silicone resin then has been prepared with trimethoxyphenyl silane (as the base material), 1,1,3,3 - tetramethyldisiloxane and hexamethyldisiloxane (as the end-capping agent) by hydrolysis condensation under acidic firstly, and then replaced by the active hydrogen groups under acidic. Step 3 : Both undergo the cross-linking reaction under the catalyst of platinum to obtain the MT phenyl curable silicone resin, with refractive index greater than 1.5, light transmittance greater than 90% and good thermal stability. It has Shore hardness from 60 A to 90 A, the tensile strength from 5. 15 MPa to 11. 35 MPa, which are good in the field of LED packaging for application. [ABSTRACT FROM AUTHOR]

In the face of the unprecedented public health crisis caused by the novel coronavirus pneumonia epidemic, front-line health workers are under enormous mental pressure. This paper aims to explore the mental health challenges faced by front-line health workers in the early stages of a public health emergency, such as stress, anxiety, and depression. At the same time, the factors that increase their mental stress are analyzed, and practical measures are put forward to prevent and manage mental health problems, aiming at improving the quality of medical treatment during public health emergencies. This paper has some reference value for people engaged in mental health prevention., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Wang, Jiang, Zhang, Wu, Zhang, Cui, Zhang and Wang.)

Objective: To identify the location and contents of the rectal lateral ligaments and its relationship with the middle rectal artery and pelvic plexus., Methods: Twenty-nine pelvics of human cadavers were sagittally sectioned into 58 hemipelvic specimens. All of hemipelvics were dissected with sharp technique under direct vision by one surgeon. The lateral ligaments were identified and the distances from the center of its pelvic attachment to sacral promontory and coccyx were measured. Then, the lateral ligaments were transected for histologic examination., Results: Lateral ligaments of rectum were found in all 58 hemipelvics. The lateral ligaments connected the posterolateral aspect of the middle 1/3 of the rectum and mesorectum to the lateral aspect of the bodies of the second, third and fourth sacral vertebrae. The distance from the lateral ligament to sacral promontory was (8.3 +/- 1.6) cm on the right side and (8.4 +/- 1.4) cm on left side. The width of lateral ligaments was (3.2 +/- 0.4) cm on the right side and (3.1 +/- 0.4) cm on the left side. The distances from lateral ligament to the coccyx on the right and left sides were (5.2 +/- 1.4) cm and (5.0 +/- 1.3) cm respectively. The content of the lateral ligaments consisted of loose connective tissue with clusters of small nerves and blood vessels. Middle rectal artery was found in 83% (48/58) of hemipelvics and 47% (27/58) of the middle rectal artery went through the lateral ligaments. The inferior hypogastric nerve plexuses were formed inside the lateral ligament, and separated the ligament into two parts. The lateral segment of the lateral ligament contained the tributaries of internal iliac artery, and the medial segment contained nerve fibers or branches to the rectum, together with the middle rectal artery., Conclusion: The lateral ligaments of rectum are located on the posterolateral side of the rectum, much closer to the coccyx than to the sacral promontory, consisting of connective tissue containing multiple small nerves and middle rectal artery. The lateral ligament is a pathway of blood vessels and nerve fibers toward the rectum and lymphatic vessels from the lower rectum toward the iliac lymph nodes.

Objective: To evaluate the accuracy of preoperative magnetic resonance imaging (MRI) in prediction of pathological staging and involvement of circumferential resection margin (CRM) in rectal cancer., Methods: Fifty-three patients undergoing total mesorectal excision for biopsy-proven rectal cancer were assessed prospectively using high-resolution MRI for tumour (T) and mesorectal nodal (N) staging as well as CRM status using the depth of tumour spread, tumour node metastasis and CRM involvement. Preoperative MRI assessment of these prognostic factors was compared with the histopathological findings in carefully matched whole-mount sections of the specimen., Results: MRI correctly staged the tumor in 41 patients, understaged in 8, and overstaged in 4. The accuracy of T stage was 77.4% (41/53). There was ageneric correlation between pathologic and MRI tumor staging (Kappa = 0.602, P < 0.001). Node status was correctly staged in 37 patients, overstaged in 10, and understaged in 6. The accuracy of node staging was 69.8% (37/53), sensitivity was 75% (18/24), and specificity was 65.5% (19/29). The correlation between pathologic and MRI node staging was poor (Kappa = 0.399, P = 0.003). The CRM status was correctly reported in 51 patients, overstaged in 1, and understaged in 1. The accuracy of CRM status was 96.2% (51/53), sensitivity was 80% (1/5), and specificity was 97.9% (47/48). There was a good correlation between pathologic and MRI CRM involvement (Kappa = 0.779, P < 0.001)., Conclusion: Preoperative MRI provides poor predictive data as to subsequent pathologic tumor and mesorectal node stage, but does produce reliable prediction of clear CRM.

Objective: Evaluation of single stapler combined with prolapsing technique for anus-preserving of ultra-low rectal cancer and its indication as well as surgical procedure., Methods: Forty-three patients with ultra-low low rectal cancer suitable for anterior resection were divided into two groups, single stapler combined with prolapsing technique was applied for experiment group, conventional double stapler technique was applied for control group. To compare the distal margin, local recurrence rate, complications, anal continence function and expenses., Results: The distal margin of experimental group is significantly longer than that of control group (2.2 cm +/- 0.2 cm VS 1.9 cm +/- 0.4 cm, P = 0.006). The distance between dentate line and distal incision line of control group is much longer than experimental group (1.9 cm +/- 0.5 cm VS 1.3 cm +/- 0.3 cm, P < 0.001). There is no recurrence in experimental group but 3 cases recurrence within 1 year in control group. The anastomose fistula rate, instrument expenses of experimental group are less than those of control group. There is no distinct in anal continence between two groups. Occasional minor soiling is present in 1 case of experimental group., Conclusion: Single stapler combined with prolapsing technique is superior to double stapler technique for anus-preserving of ultra-low rectal cancer.

Objective: To investigate the clinical application of a new temporary abdominal wound closure,vacuum system for temporary management of the open abdomen., Methods: Vacuum pack system consisted of polyethylene sheet,surgical towel,silicone drain, adhesive plastic drape. Clinical data of the patients undergoing exploratory celiotomy were recorded,and the indications for such temporary abdominal closure and its complications were reviewed., Results: Thirteen trauma patients underwent such vacuum abdominal closure for 15 times, including 5 times (33.3%) for increased intra- abdominal pressure so that tension-free fascial closure was unable to achieve, 4 times (26.7%) for reexploration, 2 times (13.3%) for damage control, and 4 times (26.7%) for combined factors. Finally, seven patients (53.8%) received direct closure and 5 patients (38.5%) received skin grafting after granulation because the defect could not be closed directly. One patient (7.7%) died before abdominal closure was attempted. None of the patients developed enterocutaneous fistula and evisceration. Three patients (23.1%) developed intra-abdominal abscess., Conclusions: The vacuum pack is a better temporary abdominal wound closure device, and primary closure can be achieved in most of the patients. The technique is simple and easily mastered with a low complication rate.

Objective: To study the correlation of vascular endothelial growth factor-C (VEGF- C) expression and lymphatic microvessel density (LMVD) with clinicopathological features and prognosis in colon cancer., Methods: The expression of VEGF-C and VEGFR-3 was detected by immunohistochemical staining with monoclonal antibodies against VEGF-C and VEGFR-3 in 44 cases with primary colon cancer. LMVD was calculated., Results: VEGF-C positive rate was 43.2% (19/44). VEGF-C expression was associated with tumor (P=0.003), lymph node metastasis (P=0.002), Dukes stage (P=0.001). The mean LMVD was 10.14+/- 4.19. LMVD was associated with lymph node metastasis (P=0.002), Dukes stage (P=0.001). LMVD in VEGF-C(+) group was (11.34+/- 4.83) higher than (9.24+/- 3.48) in VEGF-C(-) group, but there was no statistically significance between the two groups (P=0.105). The survival rate of the patients with positive VEGF-C was lower than that with negative VEGF-C (P=0.0225). The median survival time of the patients with LMVD(+) group was shorter than that with LMVD(-) (P=0.0036). Distant metastasis (P=0.0004), lymphatic metastasis (P=0.021) and LMVD (P=0.0469) were independent prognostic factors., Conclusions: VEGF-C and LMVD appear to be new prognostic factors for colon cancer. Furthermore, LMVD may be a new independent prognostic factor.