Zeolite-based hemostat QuikClot releases calcium into blood and promotes blood coagulation in vitro.

AIM: To examine the changes in electrolyte concentrations after addition of zeolite-based hemostat QuikClot in blood and the effects of zeolite on blood coagulation in vitro. METHODS: Fresh blood was taken from healthy adult volunteers and sheep, and the electrolyte concentrations in blood were measured using a blood electrolyte analyzer. Zeolite Saline Solution (ZSS) was prepared by addition of 2 g zeolite to 0.9% NaCl solution (4, 8, or 16 mL). The electrolytes in ZSS were measured using inductively coupled plasma atomic emission spectroscopy. The prothrombin time (PT) and activated partial thromboplastin time (APTT) of blood were measured using the test tube method. The activated clotting time (ACT) and clotting rate (CR) of blood were measured with Sonoclot Coagulation and Platelet Function Analyzer. RESULTS: Addition of zeolite (50 and 100 mg) in 2 mL human blood significantly increased Ca(2+) concentration, while Na(+) and K(+) concentrations were significantly decreased. Addition of zeolite (50 and 100 mg) in 0.9% NaCl solution (2 mL) caused similar changes in Ca(2+) and Na(+) concentrations. Si(4+) (0.2434 g/L) and Al(3+) (0.2575 g/L) were detected in ZSS (2 g/8 mL). Addition of ZSS in sheep blood shortened APTT in a concentration dependent manner, without changing PT. ZSS or aqueous solution of CaCl2 that contained Ca(2+) concentration identical to that of ZSS significantly shortened ACT in human blood without significantly changing CR, and the effect of ZSS on ACT was not significantly different from that of CaCl2. CONCLUSION: Zeolite releases Ca(2+) into blood, thus accelerating the intrinsic pathway of blood coagulation and shortening the clot formation time.

Epidemiological studies of electrical injuries in Shaanxi province of China: a retrospective report of 383 cases.

A statistical survey was conducted at the Burn Unit of the Tangdu Hospital, Shaanxi, China, during the 10-year period from January 2000 to December 2009. In this retrospective study, 383 patients who admitted to our burn unit because of electrical trauma were included. Data including the patient's general condition, clinical presentation, complications and operation times was collected retrospectively and analyzed with epidemiological methods. Subjects in our collective were predominantly male (90.3%, n=346/383) and were composed by those who injured in work-related incidents (78.3%, n=300/383), rural individuals (58.2%, n=223/383) and students (9.4%, n=36/383). High voltage was directly correlated to severity clinical complications, and amputation. The percentage of myocardial impairment was 79.3% (n=92/116) among patients who suffered with electrical current through heart tissue. Along with the more developed east area of China, electrical injuries are becoming a growing concern of the developing West part in China as well. Electrical injuries induce serious tissue damage, need long hospital stay, and result in high rate of permanent disability and economic hardship for the afflicted families. A competent prevention program needs to be developed to address this problem.

Electrical injury alters ion channel expression levels and electrophysiological properties in rabbit dorsal root ganglia neurons.

The electrophysiological and morphological changes of nerve fibers induced by electrical injury have been widely addressed. However, the changes of ion channels in neurons after electrical shocks have not been systematically investigated yet. In this study, the sciatic nerves of rabbit were injured by 50 V 50 Hz, 110 V 50 Hz, and 220 V 50 Hz alternating current, respectively. One week later, the expression levels and electrophysiological changes of voltage-gated potassium (Kv) and sodium (Nav) channels in dorsal root ganglia (DRG) neurons were evaluated by RT-PCR, immunofluorescence staining and patch clamp technique. The Nav1.1 expression was decreased by 50V injury. The Kv1.2, Kv1.4, Nav1.1 and Nav1.7 expression levels and Kv current densities were reduced after 110 V injury. Under the 220 V injury circumstance, Kv1.2, Nav1.1, Nav1.7 expression levels, Kv current densities and TTX-R Na(+) current densities were significantly decreased, while TTX-S Na(+) current densities increased. These findings suggest that the expression levels, subunit compositions, and electrophysiological properties of Kv and Nav channels are altered after electrical injury, and the severity of injury gets worse as injury voltage increases.

[Therapeutic effect of vacuum-assisted closure technology on infected explosion wound of pig].

OBJECTIVE: To investigate the effect of vacuum-assisted closure (V. A. C.) technology in the treatment of infected wound of skin and soft tissue as a result of explosion injury in pig. METHODS: Sixteen explosion wounds were established by electric detonators on the shoulders and hips on both sides of 4 small white domestic pigs ,and they were divided into A group [(without treatment and infection occurred on 1-2 post burn day (PBD), then treated with vaseline gauze on 3 (PBD)], and B group (with the same treatment as in A group, except for treatment of vacuum assisted closure (V. A. C) with pressure of - 15 kPa after 3 PBD). The data of wound depth, wound area, wound healing time were collected and analyzed at 3 PAD and 1, 3, 6, 9, 14, 19, 24 days after treatment. Specimens from wounds were collected for histopathology observation, including also cell proliferation index, the number of vascular endothelial cells, the activity of myeloperoxidase (MPO) and the number of bacteria. RESULTS: Compared with those in A group on land 3 days after treatment, wound area, wound depth were not enlarged or deepened in B group, while the number of inflammatory cells, vascular endothelial cells, proliferative cells were increased, the activity of MPO was enhanced and the number of bacteria was decreased. There were obvious differences between two groups in following indices: wound area ,wound depth, the number of vascular endothelial cells and bacteria during 1 to 19 days after treatment (P < 0.01)), the number of cell proliferation from 1 - 9 days after treatment (P < 0.01)), and the activity of MPO on 3, 6 days after treatment (P < 0. 01). The wound healing time was (32.8 +/- 1.6) d in A group, which was longer than that in B group (25.8 +/- 1.0 d, P < 0.01). CONCLUSION: Compared with conventional dressing change, V. A. C can decrease bacteria load, lessen secondary necrosis, prompt the inflammatory response, accelerate the formation of granulation tissue, shorten wound healing time in infectious wound of porcine skin and soft tissue resulted from explosion injury.

[The influence of vacuum-assisted drainage on the growth of capillaries in the wound produced by explosion in pig].

OBJECTIVE: To investigate the influence of vacuum-assisted closure (VAC) technique on the growth of capillaries in the wound of the pig produced by explosion. METHODS: Four small white pigs were inflicted with 16 explosion wounds [(7.3 +/- 1.0) cm2 in area] on both sides of the buttocks, shoulders and hips by detonation of a specific type of explosive, and the wounds were randomly divided into 2 groups, i. e, control (C, with conventional treatment from 2 post-injury day (PID) on and treatment (T, with VAC treatment after debridement from 2 PID on) groups, with 8 wounds in each group. Wound tissues of 2mm x 2mm x 2mm in size were harvested for pathological examination before treatment and on 1 and 3 post-treatment day (PTU). The differentiation of adventitial cells were examined with light microscope, and the pixel value of desmin positive particles and the luminal area of newly formed capillaries were assessed with Image C software. RESULTS: Most of vessels in the wound of both groups were in elliptic shape when observed in longitudinal section. In C group, few newly formed capillaries vessels with lack of pericytes were observed before treatment and on 1, 3 PTD, then the number began to increase on 6 PTD. In T group, the number of newly formed capillaries with pericytes was increased on 1 PTD, and it continued to increase thereafter. The pixel values of desmin positive particles in C group on 1, 3, and 6 PTD were (91 +/- 54), (199 +/- 85), and (1552 +/- 298), respectively, which were obviously higher than those in T group [(2569 +/- 330), (3984 +/- 377), (9611 +/- 960), P < 0.01]. The area of vessel lumen in C group was (59 +/- 36), (250 +/- 70), and (938 +/- 287) microm2, respectively on 1, 3, and 6 PTD, which was also smaller than those in T group [(818 +/- 234), (4518 +/- 1080), and (9058 +/- 1656) microm2, P < 0.01]. CONCLUSION: Compared with conventional therapy, VAC can not only accelerate the formation of new capillaries, but also enhance the differentiation of pericytes and the process of enwrapping them around the vessels, and increase the luminal area of newly formed capillaries.

[The changes in blood flow in sciatic nerve after electrical injury in rabbit].

OBJECTIVE: To study the changes in sciatic nerve blood flow and the expression of collagen type I after electric injury of rabbit nerve with different voltages. METHODS: Thirty-six healty rabbits were randomized into 3 groups before receiving injury with electricity in voltages, i.e. 50 v, 75 v, and 100 v groups. The changes in blood flow of sciatic nerve were observed with Laser Doppler Flowmeter immediately after injury and 1, 4, 8 weeks after injury. The changes in the expression of collagen type I was observed by immunohistochemical method, and the positive expression rate was calculated. RESULTS: The sciatic nerve blood flow increased in all groups immediately after electric injury. In the 75 v and 100v groups, the nerve blood flow [(53 +/- 3 ), (48 +/- 5) PU] was obviously lower than that of normal value [(62 +/- 4) PU, P < 0.05]. There was little collagen type I deposition in 50 v group, while brown collagenous fibers in epineurium and perineurium were observed in 75 v and 100v groups 4 and 8 weeks after injury. The expression of collagen type I in all groups were obviously higher than that of normal value, and that in 75v and 100 v groups were higher than that in 50 v group at bachl time-point (P < 0.01). CONCLUSION: The restoration of sciatic nerve blood flow is postponed following by the injury with increase of the electrical voltage. The collagen deposition after electrical injury may be one of the reasons for nerve blood flow decrease.

[Isolation, cultivation of adipose-derived mesenchymal stem cells and its chondrogenic ability].

AIM: To find a method for isolation and cultivation of human adipose-derived mesenchymal stem cells(ADSCs), and to investigate its chondrogenic ability. METHODS: Liposuction human adipose tissues were digested with collagenase type II. The obtained cells were primarily cultured in DMEM medium, and then changed into the induced medium. Alcian Blue stain, picrosirius red stain and the specific collagenase type II immunohistochemical staining were used to detect the results. RESULTS: After cultured in chondrogenic medium, the cells differentiated toward cartilage cells and secreted the specific cartilaginous matrices sulfated proteglycan and collagen type II. CONCLUSION: The human ADSCs have the potential ability to differentiate toward cartilage cells in the appropriated medium. The result provide a new method for the further research in cartilaginous tissue engineering.

[Effect of vacuum assisted closure on collagenase activity in human chronic wound].

OBJECTIVE: To study the variations of collagenase activity in exudates of human chronic wound before and after treatment of VAC so as to partly disclose the mechanisms of VAC in promoting chronic wound healing. METHODS: The exudates of acute wounds (postoperative breast cancer) were postoperatively collected at day 1, 2, 3, and in 6 chronic wounds (4 cases of venous ulcer, 2 cases of pressure sore) the exudates were also collected before and 2, 4, 6 days after the treatment with VAC. The type-III collagen degradation from the exudates was checked with zymography timepoint. The types of the collagenase in exudates were evaluated by using doxycycline inhibition. RESULTS: Drainage fluids from acute wound might degrade type-III collagen partly with no changes at day 1, 2, 3. There were high collagenase activities in chronic wound exudates. Exudates from patients before treatment with VAC can degrade type-III collagen completely. But collagenase activities became less and less after VAC. Doxycycline inhibition tests indicated that it can't inhibit the activity of collagenase at 100 micromol/L concentration, until it reached 600 micromol/L. CONCLUSIONS: Collagenase activity is elevated in chronic wounds. VAC may be lower the collagenase activity, prevent collagen from degrading abundantly and promote wound healing. Collagenase is mainly MMP-1 type (fibroblast-type) in chronic wound exudates.

[500 cases of external ultrasound-assisted liposuction].

OBJECTIVE: To discuss the therapeutic effects and safety of external ultrasound-assisted liposuction and to find out the rules of circumference variation in different body areas after liposuction. METHODS: External ultrasound liposuction was performed on 500 patients (595 sites). We recorded the volume of anesthetic drugs and the aspirated pure fat as well as the body contour variations of every area at one to three months postoperatively. The decreased dimension at different body sites after liposuction were compared and analyzed. RESULTS: The volumes of the anesthetic liquid and the aspirated pure fat were the most in the waist-abdomen and the thigh. After liposuction, the circumstances in different body areas were all decreased to certain degrees. Along with the severity of obesity, changes in the waist-abdomen became more obvious and the decreases of the umbilical circumference, the minimum and the maximum waist circumferences were prone to be less. But when the, minimum waist circumference was over 111 cm, obvious changes occurred in the umbilical. Meanwhile, the upper-middle part of the thigh and the upper arm showed larger variations than the lower part. The ultrasound-assisted liposuction had less blood loss and pain. It resulted in smooth skin without severe complications. CONCLUSIONS: External ultrasound-assisted liposuction is a safe, effective and easily acceptable operation for body contour remodeling. The body circumference variation may have its intrinsic rule, which, to some extent, is meaningful for conducting clinical inquiry and forecasting the operation results.