Water residence time controls seasonal nitrous oxide budget in a semi-enclosed bay: Insights from an improvement estimation method.

This study developed an estimation method for the N2O budget using 15N stable isotope labeling techniques, a dual-layer model and a box model, which was used to elucidate the underlying dynamics of N2O accumulation in Zhanjiang Bay. The results showed that although the net input of N2O during the rainy season was 2.36 times higher than that during the dry season, the overall N2O concentration was only 66.6 % of that during the dry season due to the extended water residence time in the dry season. Our findings highlighted that water residence time was the key factor for the N2O emission, and a longer water residence time was unfavorable for the efflux of N2O through hydrodynamic processes and was more conducive to the production and accumulation of N2O within the bay. This research enhanced our comprehension of N2O dynamics and provided crucial insights for refining nitrogen management strategies and mitigation efforts.

Tracks of typhoon movement (left and right sides) control marine dynamics and eco-environment in the coastal bays after typhoons: A case study in Zhanjiang Bay.

Coastal oceans are highly responsive to typhoons, making them one of the most affected regions. However, our understanding of the impact of typhoon intensity and movement path on marine dynamic processes and eco-environmental factors remains limited because there are very few on-site investigations, especially continuous field observations in the bay during typhoon events. This study investigated dual water isotopes through a continuous survey (with a 5-day interval) during ten cruises in Zhanjiang Bay, associated with two typhoons of varying intensities and landing tracks (left and right sides). After typhoons, the water mass mixing intensified and lasted for several weeks, depending on the intensity of typhoons. During the typhoon periods, there was a considerable increase in contributions from freshwater to nutrient loads; however, this contribution was higher from the stronger typhoon than the weaker one. The weaker Typhoon Lionrock, which landed on the left side of the bay, enhanced the ocean front due to onshore winds induced by the typhoon, causing intrusion of high-salinity seawater into the bay and retaining pollutants in the bay. However, when stronger Typhoon Chaba landed on the right side, offshore winds induced by counterclockwise wind stress during the typhoon resulted in more seawater flowing toward the lower and outer bay. This prevented the forming of an ocean front and played a dilution role in pollutants through its hydrodynamic process. This was primarily due to the fact that the landing trajectory of typhoons directly influenced the direction of seawater flow in Zhanjiang Bay, while the intensity of typhoons further amplifies these flow patterns. This study suggests that tracks of typhoon movement, rather than their intensity and terrestrial runoff, play a crucial role in governing marine dynamics and nutrient supplies in coastal bays during typhoon events.

Seasonal distribution of water masses and their impacts on nutrient supply in the southern Beibu Gulf.

Dual water isotopes were investigated to reveal the seasonal distribution of water masses and their impacts on nutrient supply in southern Beibu Gulf. In summer and winter, the South China Sea (SCS) water (61-69%) contributed the most to the seawater in the southern Beibu Gulf, followed by the diluted water (24-34%), and the west-Guangdong coastal current (WGCC) (5-7%) had the minimum contribution. However, the major nutrient source shifted from the diluted water in summer (39-73%) to the SCS water (57-90%) in winter. The WGCC's impact on nutrient loads was relatively small (2-10% in summer, 4-34% in winter). Our results highlight the control of nutrient supply was the SCS water (winter) and diluted water (summer), with limited influence from the WGCC, providing new insights into the impact of water mass transportation and its nutrient supply in the Beibu Gulf.

A comparative study on source of water masses and nutrient supply in Zhanjiang Bay during the normal summer, rainstorm, and typhoon periods: Insights from dual water isotopes.

Typhoons and rainstorms (rainfall >250 mm day-1) are extreme weather events that seriously impact coastal oceanography and biogeochemical cycles. However, changes in the mixing of water masses and nutrient supply induced by typhoons and rainstorms can hardly be identified and quantified by traditional methods owing to the complex hydrological conditions in coastal waters. In this study, we analysed a comparative data set of dual water isotopes (δD and δ18O), hydrological parameters, nutrients, and chlorophyll-a from three periods (normal summer, rainstorm, and typhoon periods) in Zhanjiang Bay, a typical semi-enclosed mariculture bay in South China, to address this issue. The results revealed a significant increase in contributions from freshwater during rainstorms and typhoons. Correspondingly, nutrient supplies from freshwater during these periods remarkably increased compared to the normal summer, indicating that heavy rainfall can transport substantial amounts of terrestrial nutrients into the bay. Furthermore, disparities in hydrodynamic processes between typhoon and rainstorm periods were notable due to inconsistencies in freshwater diffusion paths. During rainstorms, freshwater primarily diffuses towards the outer bay in the upper layer due to strong stratification and cannot form an ocean front. However, under intense external forces caused by the typhoon, high-salinity water intruded into the bay, and enhancement of vertical mixing disrupted stratification. The massive influx of freshwater column during the typhoon mixed with higher salinity seawater column in the bay led to the formation of an ocean front, which could retain contaminants. This study suggests that although both rainstorms and typhoons can discharge large quantities of terrestrial nutrients into Zhanjiang Bay, the front formed during the typhoon period impedes the contaminant transportation to open sea thereby deteriorating water quality and affecting mariculture activities within the bay.

The modified second toe flap technique based on the dorsal digital artery of the toe in finger pulp reconstruction.

BACKGROUND: The second toe flap is a widely used innervated neurovascular flap for repairing finger pulp defects. It mainly carries the proper plantar digital artery and nerve. But the donor site morbidity and arterial injury are common. The report retrospectively evaluated the clinical outcomes of the second toe free medial flap based on dorsal digital artery of the toe to investigate the esthetics and function in the treatment of soft tissue defects of fingertip pulp. METHODS: From March 2019 to December 2020, 12 patients with finger pulp defects (seven acute crush, three cut, and two burn) undergoing the modified second toe flap were chosen for retrospective review. The average patient age was 38.6 (range: 23-52) years. The mean defect size was 2.1 × 1.6 (range: 1.5 × 1.3-2.6 × 1.9) cm. The defects did not extend beyond the distal interphalangeal joint and the phalanges were not damaged in all cases. The average follow-up was 9.5 (range: 6-16) months. Demographic information, flap data, and perioperative characteristics were collected. RESULTS: The mean size of the modified flap was 2.3 × 1.8 (range: 1.7 × 1.5-2.7 × 2.0) cm and mean diameter of artery was 0.61 (range: 0.45-0.85) mm. The mean flap harvested time and operation time were 22.6 (range: 16-27) minutes and 133.7 (range: 101-164) minutes. A flap was ischemic after first day postoperatively and later it improved by releasing the sutures. All flaps were survival without necrosis. One patient was not satisfied with the appearance of the finger pulp because of scar hyperplasia. The other 11 patients were satisfied with the appearance and function of the injured digit after 6 months postoperatively. CONCLUSION: The modified second toe flap technique based on the dorsal digital artery of the toe is a feasible choice to reconstruct the sensation and appearance of the injured fingertip with current microsurgical techniques.

Spatial and Temporal Variations and Risk Assessment of Heavy Metal Fractions in Sediments of the Pearl River Estuary, Southern China.

Sequential extraction was used to study the mobility and ecological risk of chemical fractions of six heavy metals in sediments collected from the Pearl River Delta (PRE) in China. Results revealed that residual fractions (F4) were the dominant forms for Cr and Ni in surface sediments, indicating that they were primarily stable in nature and had low bioavailability and ecotoxicity. Cd had a high environmental risk owing to its higher availability in acid-soluble fraction (F1), whereas Pb occurred predominantly in the reducible fraction (F2) in surface sediments. The profile variations of bioavailable fractions were generally consistent with socioeconomic development in the Pearl River Delta (PRD). A decreasing trend after 2006 suggested a reduction in heavy metal bioavailable fractions owing to the removal of heavy polluting industries and the effective control of sewage discharge. The risk assessment code suggested that the high mobility of Cd posed an extremely high risk and a threat to the aquatic environment.

Consequences of anthropogenic activities and beach dynamics on vertical distribution of microplastics in the mid-intertidal sediments of Donghai Island, China.

Microplastic accumulation and resulting degradation are significant threats to the coastal ecosystems around the world. Baseline information on microplastics and their sources is of great importance for a permanent waste management system. The present study focused on the vertical distribution and characteristics of microplastics in the mid-intertidal zone of Donghai Island, China. At eight locations, sediment samples were collected from surface to a depth of 30 cm at intervals of 5 cm. Overall, we found five different polymer types, and vertical distributions of microplastics varied ranging from 0 to 200 particles/kg, with the mean value of 32.92±41.35 particles/kg. Sediment samples collected from all stations contained microplastics with high contribution of fibres. Intruded microplastic materials recorded in sediment samples at a depth of 30 cm demonstrate that microplastics may be present at depths greater than 30 cm. Scanning electron microscopy-energy dispersive X-ray (SEM-EDAX) analysis revealed presence of common elements in the microplastics surface (silicon, aluminium, magnesium, copper, and calcium). Based on the observations and results from this study, we suggest implementing a robust microplastic removal management program in Donghai Island to avoid serious microplastic intrusion effects on benthos and environmental contamination.

Bioprinting small-diameter vascular vessel with endothelium and smooth muscle by the approach of two-step crosslinking process.

Three-dimensional bioprinting shows great potential for autologous vascular grafts due to its simplicity, accuracy, and flexibility. The 6-mm-diameter vascular grafts are used in clinic. However, producing small-diameter vascular grafts are still an enormous challenge. Normally, sacrificial hydrogels are used as temporary lumen support to mold tubular structure which will affect the stability of the fabricated structure. In this study, we have developed a new bioprinting approach to fabricating small-diameter vessel using two-step crosslinking process. The » lumen wall of bioprinted gelatin mechacrylate (GelMA) flat structure was exposed to ultraviolet (UV) light briefly for gaining certain strength, while ¾ lumen wall showed as concave structure which remained uncrosslinked. Precrosslinked flat structure was merged towards the uncrosslinked concave structure. Two individual structures were combined tightly into an intact tubular structure after receiving more UV exposure time. Complicated tubular structures were constructed by these method. Notably, the GelMA-based bioink loaded with smooth muscle cells are bioprinted to form the outer layer of the tubular structure and human umbilical vein endothelial cells were seeded onto the inner surface of the tubular structure. A bionic vascular vessel with dual layers was fabricated successfully, and kept good viability and functionality. This study may provide a novel idea for fabricating biomimetic vascular network or other more complicated organs.

Coastal currents regulate the distribution of the particulate organic matter in western Guangdong offshore waters as evidenced by carbon and nitrogen isotopes.

The δ13C, δ15N and C/N ratio of the particulate organic matter (POM) in western Guangdong waters were determined to evaluate the impacts of the coastal currents on the POM in spring and summer. The predominance of photosynthetic organic matter in the nearshore was triggered by nutrients brought by the coastal currents in spring and summer, while the proportion of terrestrial organic matter in the offshore was very high in spring but low in summer. In spring, the weaker and narrower coastal currents carried insufficient nutrients (phosphate deficiency) to the offshore and prohibited phytoplankton production. This scenario contributes to the dominance of terrestrial organic matter transported by the cyclonic circulation beyond the coastal currents in the offshore in spring. The Bayesian mixing model reveals that the proportion of terrestrial organic matter (with 75.8% of C3 plants) in the offshore was higher in spring than in summer (with 33.7% of C3 plants).

Mechano-regulation of vascular network formation without branches in 3D bioprinted cell-laden hydrogel constructs.

Restoration of a wound is a common surgical procedure in clinic. Currently, the skin required for clinical use is taken from the patient's own body. However, it can be difficult to obtain enough skin sources for large-sized wounds and thus surgeons have started using commercial skin substitutes. The current commercial skin, which includes epidermis substitute, dermis substitute, and bilateral skin substitute, has been popularized in clinic. However, the application is limited by the occurrence of ischemia necrosis after transplantation. Recent studies suggest the use of pre-vascularized skin substitutes for wound healing is a promising area in the research field of skin tissue engineering. Pre-vascularization can be induced by changes in cultivation periods, exertion of mechanical stimuli, or coculture with endothelial cells and various factors. However, few methods could control the formation of vascular branches in engineering tissue in a self-assembly way. In this study, we use three-dimensional (3D) printing technology to confirm that a mechanical force can control the growth of blood vessels in the direction of mechanical stimulation with no branches, and that Yes-associated protein activity is involved in the regulatory progress. In vivo experiments verified that the blood vessels successfully function for blood circulation, and maintain the same direction. Results provide a theoretical basis for products of pre-vascularized skin tissues and other organs created by 3D bioprinting.

Carbon and nitrogen isotopic compositions of particulate organic matter in the upwelling zone off the east coast of Hainan Island, China.

The isotopic compositions (δ13C and δ15N) and C/N ratios of suspended particulate organic matter (POM) were investigated off the east coast of Hainan Island in the South China Sea during summer. Coastal upwelling influenced the nearshore stations of transects S2 and S3, and higher δ13C and δ15N values suggested that coastal upwelling played a significant role in determining the POM sources. The POM at the nearshore area of transect S1 was controlled by the coastal current and freshwater discharge. Additionally, organic matter may be transported to the offshore area via tidal movements in transects S1 and S3. Based on the stable isotope analysis in an R model, the marine organic matter contribution in the upwelling area (19%) was higher than that in the other areas (transect S1 and the offshore area) (7%). The δ13C and δ15N values and C/N ratios reflect the carbon and nitrogen sources and their cycling in the upwelling zone off the east coast of Hainan Island.

Quercetin promotes human epidermal stem cell proliferation through the estrogen receptor/ß-catenin/c-Myc/cyclin A2 signaling pathway.

Skin epidermal stem cells (EpSCs) play an important role in wound healing. Quercetin is a phytoestrogen reported to accelerate skin wound healing, but its effect on EpSCs is unknown. In this study, we investigated the effect of quercetin on human EpSC proliferation and explored the underlying mechanisms. We found that quercetin at 0.1~1 µM significantly promoted EpSC proliferation and increased the number of cells in S phase. The pro-proliferative effect of quercetin on EpSCs was confirmed in cultured human skin tissue. Mechanistic studies showed that quercetin significantly upregulated the expressions of ß-catenin, c-Myc, and cyclins A2 and E1. Inhibitor for ß-catenin or c-Myc significantly inhibited quercetin-induced EpSC proliferation. The ß-catenin inhibitor XAV-939 suppressed quercetin-induced expressions of ß-catenin, c-Myc, and cyclins A2 and E1. The c-Myc inhibitor 10058-F4 inhibited the upregulation of c-Myc and cyclin A2 by quercetin. Pretreatment of EpSCs with estrogen receptor (ER) antagonist ICI182780, but not the G protein-coupled ER1 antagonist G15, reversed quercetin-induced cell proliferation and upregulation of ß-catenin, c-Myc, and cyclin A2. Collectively, these results indicate that quercetin promotes EpSC proliferation through ER-mediated activation of ß-catenin/c-Myc/cyclinA2 signaling pathway and ER-independent upregulation of cyclin E1 and that quercetin may accelerate skin wound healing through promoting EpSC proliferation. As EpSCs are used not only in clinic to treat skin wounds but also as seed cells in skin tissue engineering, quercetin is a useful reagent to expand EpSCs for basic research, skin wound treatment, and skin tissue engineering.

210Pb dating to investigate the historical variations and identification of different sources of heavy metal pollution in sediments of the Pearl River Estuary, Southern China.

In this study, we investigated the historical variation, source identification, and distribution of heavy metal pollution in sediments of the Pearl River Estuary (PRE) using 210Pb dating. Our results suggest that the heavy metal concentrations were higher in the western part of the estuary. For all heavy metals, Cd was significantly enriched in the sediments. The Pearl River Delta (PRD) has experienced rapid economic development in the past 40 years, a decreasing trend in heavy metal fluxes after 2004 was identified, which suggests a reduction in heavy metal concentrations due to the removal of heavy polluting industries and the effective control of sewage discharge. A binary mixing model reveals that the contributions of anthropogenic Pb ranged from 45.4 to 64%. Based on lead isotopic ratios (206/207Pb and 208/206Pb), it was found that geologic materials and industrial pollution were the main sources of heavy metals in the PRE sediments.

Isotopic evidence for the shift of nitrate sources and active biological transformation on the western coast of Guangdong Province, South China.

Dual isotope nitrate (NO3-) analysis was performed on the western coast of Guangdong Province to investigate seasonal changes in the main nitrate sources and their biogeochemical processing, which are due to the rapid development of the local economy. In the nearshore area, significant seasonal variations of nitrate sources occurred. The dominant nitrate sources, originating from manure and sewage, suggested that the nitrate along the west coast of Guangdong Province was mainly influenced by local cities despite the westward flow of diluted Pearl River water. In the offshore area, the nitrate loss in the upper and mid water during both two seasons mainly caused by phytoplankton assimilation, whereas coupled nitrification-denitrification could be responsible for the nitrate loss in the bottom waters during summer. Our results suggest that, with the rapid development of local economy, the nitrate sources in the coastal area have shifted to manure and sewage from the local cities.

Dual isotopic evidence for nitrate sources and active biological transformation in the Northern South China Sea in summer.

Nitrate (NO3-) concentrations and their dual isotopic compositions (δ15N-NO3- and δ18O-NO3-) were measured to constrain N sources and their cyclic processes in summer using samples from the water column of the northern South China Sea (NSCS). Our data revealed that higher NO3- concentrations and δ15N-NO3- values were observed in the upper waters of the coastal areas near the Pearl River Estuary (PRE). The Bayesian stable isotope mixing model was used to calculated the proportion of nitrate sources, the results indicated that the nitrate in the upper waters of the coastal areas near PRE were mainly influenced by manure and sewage (63%), atmospheric deposition (19%), soil organic nitrogen (12%) and reduced N fertilizer (6%). For the upper waters of the outer areas, low NO3- concentrations and δ15N-NO3- values, but high δ18O-NO3- values, reflected that NO3- was mainly influenced by Kuroshio water intrusion (60%), atmospheric deposition (32%) and nitrogen fixation/nitrification (8%). Complex processes were found in bottom waters. Nitrification and phytoplankton assimilation may be responsible for the higher nitrate concentrations and δ15N-NO3- values. Our study, therefore, utilizes the nitrate dual isotope to help illustrate the spatial variations in nitrate sources and complex nitrogen cycles in the NSCS.

Replantation or revascularization for the treatment of hand degloving injuries.

PURPOSE: The purpose of this study was to explore effective strategies of replantation or revascularization for the treatment of hand degloving injuries. METHODS: Ten patients who had received replantation or revascularization surgery for hand degloving injury between 2002 and 2014 were included for this study. The average age at the time of surgery was 34.5 years (range 18-49 years). There were nine left and one right hand replantations. The cause of injury was an industrial machine press in all of them. The skin was avulsed from the palm to the distal phalangeal level in five patients, to the middle phalangeal level in four patients, and avulsed from the wrist crease level completely in one patient. All the degloved flaps were revascularized. RESULTS: Both the degloved flap and phalanges survived completely in one patient, and partial survival of the flap occurred in the remaining patients. The patients were followed up from 15 months to 78 months (average, 38.1 months). Sensory recovery of the finger pulp ranged from S2 to S3+. Michigan Hand outcome Questionnaire (MHQ) score ranged from 29 to 96 with an average of 69.5. CONCLUSIONS: Midlateral incision to reduce the secondary damage to the capillaries, repair of more vessels for circulation, application of full-thickness skin grafts to enlarge the survival area, and use of anticoagulation protocols during and postsurgery may be beneficial to improve the replantation survival of the degloved skin.

Comparison of treatment outcomes between nonsurgical and surgical treatment of distal radius fracture in elderly: a systematic review and meta-analysis.

PURPOSE: The best treatment of distal radius fractures (DRFs) in the elderly is uncertain. The purpose of this meta-analysis was to compare the outcomes of surgical and nonsurgical management of DRFs in persons 65 years of age or older. METHODS: Medline, Cochrane, EMBASE, and Google Scholar databases were searched until April 27, 2015 using the following search terms: distal radius fracture, conservative treatment, nonoperative treatment, nonsurgical treatment, surgical treatment, operative, elderly, and older. The primary outcome measure was DASH score, and secondary outcomes were functional and radiological assessments. The standard difference in post-treatment means was calculated for the outcomes to compare the two groups. RESULTS: Of 59 articles identified, eight studies with a total of 440 patients in the surgical groups and 449 in the control groups were included in the analysis. No significant differences in DASH score, VAS pain score, grip strength, wrist extension, pronation, or supination, and ulnar deviation were noted between the groups. The nonsurgical group had significantly greater wrist flexion, radial deviation, and ulnar variance and less radial inclination than the surgical group. CONCLUSIONS: Surgical and nonsurgical methods produce similar results in the treatment of DRFS in the elderly, and minor objective functional differences did not result an impact on subjective function outcome and quality of life.

Combined ipsilateral and contralateral second toe flaps for repair of finger degloving injury.

PURPOSE: The purpose of this report was to retrospectively review the results of treatment of degloving injury of the finger by use of combined ipsilateral second dorsal nail-skin flap and contralateral medial second toe flap. METHODS: From 2010 to 2012, seven fingers in seven patients with complete degloving injuries from the level of middle or distal phalanx were reconstructed with combined ipsilateral second dorsal nail-skin flap and contralateral medial second toe flap. The injured fingers included the index finger in four cases, and middle finger in three cases. The nerves of both the flaps were sutured to the bilateral common digital nerves. The donor site of second toe flap was covered with a full-thickness skin graft. RESULTS: All transferred flaps survived after surgery, and all postoperative courses were uneventful. During the follow-up period (mean of 15 months; ranging 6-20 months), the appearance of the reconstructed fingers was comparable with normal ones. The range of motion of the distal interphalangeal joint averaged 55 ± 5.8 degrees. The two point discrimination of the pulp ranged from 8 to > 15 mm (average, 11.3 mm). All the patients were able to walk without difficulty. The MHQ score averaged 59 ± 4.2 points and Maryland foot rating score averaged 92 ± 4.2 points. CONCLUSION: The ipsilateral second toe dorsal nail-skin flap combined with contralateral medial second toe flap may provide an alternative for the reconstruction of completely degloved fingers at the middle and the distal phalangeal level, with satisfactory functional and cosmetic results.

[Neurovascular free flap based on dorsal branch of digital artery of ring finger for finger pulp defect].

OBJECTIVE: To investigate the surgical procedures and clinical outcomes of the neurovascular free flap based on dorsal branch of digital artery of ring finger graft for repair of finger pulp defect. METHODS: From February 2006 to May 2009, 11 cases (11 fingers) of finger pulp defect with tendon and bone exposure were treated, including 8 males and 3 females with an average age of 29 years (range, 23-40 years). The defect locations were thumb in 2 cases, index finger in 5 cases, and middle finger in 4 cases. The defect size ranged from 1.0 cm x 1.0 cm to 2.5 cm x 2.0 cm. The time from injury to operation was 1-9 hours. The flap size ranged from 1.5 cm x 1.5 cm to 3.0 cm x 2.5 cm. Five flaps carried the dorsal branch of digital nerve, 6 flaps carried nervi digital dorsales. The flaps were cut from proximal radial dorsal ring finger in 4 cases and from proximal ulnar dorsal ring finger in 7 cases. Defect of donor site was repaired with full-thickness skin grafting. RESULTS: All flaps and grafted skins survived; wound and incision of donor site achieved healing by first intention. Eleven patients were followed up 6 to 24 months with an average of 12 months. The other finger flaps had good texture and shape except for 1 flap with slightly bloated. The activities of finger distal interphalangeal joint were normal, the two-point discrimination of finger pulp was 7-12 mm. The extension and flexion activities of donor fingers were normal, the ringlike thread scar left at the donor site. CONCLUSION: It is an ideal method to use the neurovascular free flap based on dorsal branch of digital artery of ring finger graft for repair of finger pulp defect, which has the advantages of simple operation, good appearance, and functional recovery.

[Repair of whole-hand destructive injury and hand degloving injury with transplant of pedis compound free flap].

OBJECTIVE: To investigate the surgical method and clinical efficacy of repairing whole-hand destructive injury or hand degloving injury with the transplant of pedis compound free flap. METHODS: From February 2003 to June 2008, 21 patients with whole-hand destructive injury or hand degloving injury were treated, including 15 males and 6 females aged 18-45 years old (average 25 years old). The injury was caused by punching machine crush in 10 cases, roller crush in 7 cases, and imprinter crush in 4 cases. The time between injury and operation was 1-9 hours. Eleven cases had the skin-degloving injury of the whole hand, while the other 10 cases had the proximal palm injury combined with dorsal or palmar skin and soft tissue defect. After debridement, the size of wound was 9 cm x 7 cm-15 cm x 10 cm in the dorsal aspect and 10 cm x 7 cm-6 cm x 10 cm in the palmar aspect. The defect was repaired by the thumbnail flap of dorsalis pedis flap and the second toenail flap of dorsalis pedis flap in 5 cases, the thumbnail flap of dorsalis pedis flap and the second toe with dorsalis pedis flap in 4 cases, and bilateral second toe with dorsalis pedis flap in 12 cases. The flap area harvested during operation ranged from 6 cm x 5 cm to 16 cm x 11 cm. Three fingers were constructed in 2 cases and two fingers in 19 cases. Distal interphalangeal joint toe amputation was conducted in the thumbnail flap donor site, metatarsophalangeal joint toe amputation was performed in the second toenail flap donor site, and full-thickness skin grafting was conducted in the abdomen. RESULTS: At 7 days after operation, the index finger in 1 case repaired by the second toenail flap suffered from necrosis and received amputation, 1 case suffered from partial necrosis of distal dorsalis pedis flap and recovered after dressing change, and the rest 42 tissue flaps survived. Forty-three out of 44 reconstructed fingers survived. All the wounds healed by first intention. At 2 weeks after operation, 2 cases had partial necrosis of the donor site flap and underwent secondary skin grafting after dressing change, the rest skin grafts survived, and all the wounds healed by first intention. Nineteen cases were followed up for 6-36 months (average 11 months). The flaps of palm and dorsum of hand showed no swelling, the reconstructed fingers had a satisfactory appearance and performed such functions as grabbing, grasping, and nipping. The sensory of the flaps and the reconstructed fingers recovered to S2-S4 grade. The donor site on the dorsum of the foot had no obvious scar contracture, without obvious influence on walking. CONCLUSION: For the whole-hand destructive injury or hand degloving injury, the method of transplanting pedis compound free flap can repair the defect in the hand and reconstruct the function of the injured hand partially. It is an effective treatment method.