[Research advances on the application of free flaps in repairing diabetic foot ulcers]

Free flaps have been successfully used in the repair of diabetic foot ulcers (DFUs), which can reduce amputation rate, maintain normal gait of patients, and improve life quality of patients. However, there are still many challenges in the repair of DFUs with free flaps, and many problems need to be solved. This paper summarizes the selection of patients, preoperative cautions, types of flaps, methods of vascular anastomosis, clinical effects, and existing problems in using free skin flaps for repairing DFUs.

[Comparison of short-term clinical outcome between laparoscopic distal pancreatectomy and open distal pancreatectomy]

Objective: To compare the short-term clinical effect between laparoscopic distal pancreatectomy (LDP) and open distal pancreatectomy (ODP). Methods: We performed a retrospective study on 161 patients who underwent pancreatectomy between September 2017 to December 2018 in the Department of Pancreatic and Gastric Surgery, Cancer Hospital of Chinese Academy of Medical Sciences. According to the mode of operation, the patients were divided into the LDP group (n=43) and the ODP group (n=118). To compare the short-term clinical effect and safety between the LDP group and the ODP group, the preoperative clinical data, intraoperative related index, postoperative complication, postoperative recovery index, preoperative and postoperative inflammatory index were analyzed. Results: The preoperative clinical characteristics between the LDP group and the ODP group were not statistically different (P>0.05). The intraoperative blood loss in LDP group was (194.19±241.83) ml, significantly less than (315.17±295.94) ml in ODP group (P<0.05), and the postoperative exhaust time in LDP group was (3.00±0.72) days, significantly shorter than (4.05±0.97) days in OPD group (P<0.001). The time to get out of bed in LDP group was (3.14±1.01) days, significantly shorter than (3.55±1.05) days in OPD group (P<0.05). The postoperative eating time in LDP group was (3.88±1.61) days, significantly shorter than (5.11±1.56) days in ODP group (P<0.001). The time of the drainage tube removal in LDP group was (8.44±1.93) days, significantly shorter than (9.82±3.70) days in ODP group (P<0.05). The postoperative hospital stay in LDP group was (9.65±3.57) days, significantly shorter than (11.99±6.57) days in ODP group (P<0.05). The mean operation time in LDP group was (168.65±55.45) min, shorter than (171.23±65.61) min in ODP group, but without significant difference (P>0.05). The incidences of non-pancreatic fistula-related complications in LDP group and ODP group were 16.3% and 11.0%, respectively, without statistical significance (P>0.05). The incidences of pancreatic fistula in LDP group and ODP group were 16.3% and 19.5%, respectively, without statistical significance (P>0.05). The total incidences of complications in LDP group and ODP group were 32.6% and 30.5%, respectively, without statistical significance (P>0.05). The preoperative and postoperative inflammatory indexes between these two groups were not statistically different (P>0.05). Conclusions: Compared with ODP, LDP has the advantages of less intraoperative blood loss, faster postoperative recovery, shorter postoperative hospital stays, without increased postoperative complications and prolonged operation time. LDP is a safe and feasible operation method, and its short-term clinical effect is better than that of ODP.

Fabrication and microwave absorption properties of carbon-coated cementite nanocapsules

By utilizing a simple and low-cost arc-discharge method in either liquid nitrogen or ethanol at ambient temperature and pressure, carbon-coated cementite (Fe3C) nanocapsules, with size ranges of 10–60 nm and 10–20 nm, respectively, have been synthesized on a large scale. The Fe3C/C nanocapsules synthesized in different media possess similar permeability but different permittivity, which results from the different defect amounts within the carbon shell. It has been found that the as-prepared products exhibit different electromagnetic wave absorption abilities: for the ones prepared in liquid nitrogen, the optimal reflection loss is above -10 dB in the range of 1-18 GHz with the thickness ranging from 1 to 10 mm; meanwhile, for those fabricated in ethanol, the reflection loss could be below -20 dB within the thickness range of 1.5-2.4 mm in the frequency range of 10-15 GHz, and reach -38 dB at a thickness of 1.9 mm with a matching frequency of 12.9 GHz. This indicates that the nanocapsules prepared in ethanol exhibit good electromagnetic wave absorption properties. These results provide a new way to fabricate carbon-coated Fe3C nanocapsules with the ability of electromagnetic wave absorption.

Incidence of presumed cytomegalovirus retinitis in HIV-infected pediatric patients

INTRODUCTION

Large population studies of adult patients suggest an incidence of cytomegalovirus (CMV) retinitis as high as 19% to 20% as a late complication of adult HIV infection. We conducted this prospective study of a large cohort of HIV-infected children to determine the incidence of CMV retinitis in HIV-infected children.

METHODS

From January 1984 to August 1997, 173 HIV-infected children were followed up for an average of 55.3 months (13-164 months). The patients were seen in the Department of Pediatrics at least once every 6 months. Ophthalmologic examinations were initiated when a patient's CD4 count dropped below 50 or sooner if required for ophthalmologic or other indications. Ophthalmologic examination was then repeated every 6 months.

RESULTS

A total of 116 (67%) of 173 patients underwent ophthalmologic examination. Four (3.4%) of 116 patients had CMV retinitis at a mean time of 17.3 months (8-38 months) after their CD4 counts dropped below 20. None of the 4 patients with CMV retinitis had subjective visual complaints despite advanced retinitis. Three patients had bilateral and 1 patient had unilateral CMV retinitis.

CONCLUSIONS

CMV retinitis occurred infrequently in HIV-infected pediatric patients and was diagnosed only in patients with a CD4 count below 20. Routine ophthalmologic screening examinations may not be necessary in pediatric patients until the CD4 count is below 20. Because children may not complain of decreased vision, at-risk children should undergo frequent ophthalmologic examination.