The Genotoxic Effect of Gunshot Wounds

Evidence for alterations in chromosomes of experimental animals (rats) and humans after gunshot wounds is presented. The rate of chromatid exchanges induced by gunshot wounds in humans depends on the saturation of body tissues with ascorbic acid. It is assumed that free-radical processes underlie the deleterious effect of gunshot wounds on chromosomes.     

The genotoxic effect of gunshot wounds

Evidence for alterations in chromosomes of experimental animals (rats) and humans after gunshot wounds is presented. The rate of chromatid exchanges induced by gunshot wounds in humans depend on the saturation of body tissues with ascorbic acid. It is assumed that free-radical processes underlie the deleterious effect of gunshot wounds on chromosomes.     

Changes in the lipid peroxidation activity and intensity of tissue respiration during healing of aseptic and infected wounds in animal experiments

The variance of lipid peroxidation (LPO) was studied by the concentrations of malonic dialdehyde (MDA) in the tissue of wound bed and blood serum on the model of surface musculocutaneous aseptic and infected wounds simulated in 250 rats. The speed of oxygen consumption by isolated wound tissue was determined simultaneously. It was stated that the time course of MDA concentration in wounds and sera as well as tissue respiration in animals with infected wounds differed from those in animals with aseptic wounds. In a whole, MDA levels were found to be higher in cases with infected wounds and of changeable character. The latter animals demonstrated less intensive respiration of granulation tissue. Correlation between the variance of tissue respiration and MDA levels was established as was that of LPO and respiration with the phases of wound process. The findings could be used for the development of pathogenetic therapy and evaluation of its efficacy.     

Chemokine changes during oral wound healing

The oral mucosa is susceptible to tissue injury from many causes, including infection, autoimmune disorders, surgical and accidental trauma, and gingival and periodontal inflammation; however, little is known about the events that influence wound healing in the mouth. Recent studies in non-oral tissues have implicated immune system-derived factors, in particular chemokines, in the wound healing process. Tissues from mice with experimental gingival wounds were studied for expression of genes for four chemokine ligands or receptors (CCL19, CCL20, CCL25, and CCR5) that are important in leukocyte trafficking or inflammation. Notably, during the peak phase of wound healing, chemokine gene expression was up-regulated for CCL19, CCL20, and CCL25, and down-regulation of CCR5, suggesting an orchestrated process of chemokine-mediated recruitment or retention of lymphocytes and macrophages into wound areas, while simultaneously suppressing a potentially adverse inflammatory response. These findings have implications for developing therapeutic strategies aimed at promoting more effective tissue healing at oral surfaces.     

Efficacy of Butea monosperma on dermal wound healing in rats

Wound healing occurs as a fundamental response to tissue injury. Several natural products have been shown to accelerate the healing process. The present investigation was undertaken to determine the efficacy of topical administration of an alcoholic bark extract of Butea monosperma (B. monosperma) on cutaneous wound healing in rats. Full-thickness excision wounds were made on the back of rat and B. monosperma extract was administered topically. The granulation tissue formed on days 4, 8, 12 and 16 (post-wound) was used to estimate total collagen, hexosamine, protein, DNA and uronic acid. The extract increased cellular proliferation and collagen synthesis at the wound site, as evidenced by increase in DNA, total protein and total collagen content of granulation tissues. The extract treated wounds were found to heal much faster as indicated by improved rates of epithelialization and wound contraction, also confirmed by histopathological examinations. Also, the tensile strength of drug-treated wounds was increased significantly. In addition, we show that B. monosperma possesses antioxidant properties, by its ability to reduce lipid peroxidation. The results clearly substantiate the beneficial effects of the topical application of B. monosperma in the acceleration of wound healing.     

Biosorptive-flotation of copper(II) from environmental water samples using sugar beet pulp as sorbent and oleic acid as surfactant

Abstract

Wounds are likely to have existed ever since mankind has existed. Wound healing is an enormously complicated process and the actual scientific mechanisms and events that take place during healing are far more complex and dynamic than might be imagined. Essential elements, especially trace elements are believed to be pivotal to the wound healing process. Their involvement in tissue regeneration and repair appears to be wide ranging and their deficiencies have been reported to impair the healing process. However, further research is required to establish the involvement of trace elements and their specific species in the wound healing process.

Thus assessments of trace element levels in wound tissues using new, reliable, verified and validated technologies could be beneficial for trace element based wound healing. Here, is an attempt made to assess the link between trace element concentrations and healing processes of chronic and acute wounds. Wound tissue samples from 58 chronic leg ulcers and 50 acute wounds were analysed for concentrations of Fe, Zn, Cu, Mn, Ca, Sn, Cr, Cd and Pb using atomic absorption spectrophotometer. Blood samples were also collected from the same patients and analysed in the same manner. All the data were tested for normality by Ryan–Joiner normality test (α = 0.05) and one-way ANOVA was done for the normally distributed data.

The results showed that the concentration of Ca, Zn, Cu and Mn were similar in both acute and chronic wounds. Apart from Ca, which showed elevated concentrations, other metal concentrations are either similar or lower than the analysed concentrations in blood. It appears that there is a significant difference in the concentrations of iron accumulated in the tissues of chronic and acute wounds.

The concentrations of Sn, Cr, Cd and Pb, which are considered as toxic metals, were not present in detectable levels with the graphite furnace atomic absorption spectrophotometry in both types of wound tissues.     

Differences in the Element Contents Between Gunshot Entry Wounds with Full-jacketed Bullet and Lead Bullet

To elucidate characteristics of gunshot residues in gunshot entry wounds with full-jacketed and lead bullets, element contents in entry gunshot wounds and control skins were analyzed by inductively coupled plasma-atomic emission spectrometry (ICP-AES). It was found that a high content of Fe and Zn was deposited in the gunshot entry wounds with full-jacketed bullet, whereas a high content of Pb was deposited in the gunshot entry wounds with lead (unjacked) bullet. It should be noted that the content of Pb was significantly higher in the gunshot entry wounds with lead bullet than in those with full-jacketed bullet. Regarding the relationships among elements, it was found that there were significant direct correlations between Pb and either Sb or Ba contents in both gunshot entry wounds with full-jacketed and lead bullets. As Pb increased in both gunshot entry wounds, Sb and Ba also increased in the wounds.     

Tissue dispersion and flow cytometry for the cellular analysis of wound healing

Injury induces a flux in the cellular composition of tissues as part of the wound healing response. There is no reliable and rapid method to quantify and characterize the cellular composition of the matrix-rich wound. Our aim was to develop a rapid method to quantify the cellular composition in wounds by tissue dispersion and flow cytometry. Age- and weight-matched mice were wounded on the dorsum using a 1.5 x 1.5 cm2 template, and the wounds were excised at predetermined time points. Tissues were dispersed into single-cell suspensions and labeled with antibodies to cell surfaces and intracellular antigens. Flow cytometry was performed to quantify the percentage of each cell population and cell death. We found that our tissue dispersion protocol resulted in low cell death (4%-6%) and very high yield (80-220 x 10(6) cells/g). Furthermore, cell surfaces and intracellular antigens were preserved to provide accurate identification of the different cell populations. With the appropriate modifications, this protocol is likely to be applicable for the viable retrieval and identification of cells from skin and other collagen-dense tissues.     

Wound fluid bacterial levels exceed tissue bacterial counts in controlled porcine partial-thickness burn infections

In the present study, an established controlled burn wound model was used to test the hypothesis that controlled surface contamination with is capable of generating a noninvasive method for the creation of a reproducible deep tissue burn wound infection. Using a liquid tight-wound chamber in Yorkshire pigs, partial-thickness burns were inoculated with saline-immersed for 24 hours. Noninoculated burns and unwounded skin immersed in normal saline served as controls. Bacterial cultures of wound fluid were performed daily, and tissue biopsies for bacteriological and histological evaluations were performed on days 1, 3, and 5. was only recovered from -inoculated wounds (tissue and fluid), whereas all controls contained endogenous only. The number of colony-forming units per gram of wound tissue did not correlate with the bacterial counts found in the overlying wound fluid for any wounds. Fluid counts were consistently higher than tissue counts by two logs. -inoculated wounds showed three times deeper tissue destruction than control wounds. Obtaining consistently deep tissue colonization without cross-contamination among wounds, this study introduces a noninvasive model for controlled burn wound infection suitable for future investigations regarding the efficacy of topical antibiotic wound treatment in experimental burns.     

Efficacy of l-proline administration on the early responses during cutaneous wound healing in rats

Proline (Pro) plays a versatile role in cell metabolism and physiology. Pro and hydroxypro are major imino acids present in collagen, an important connective tissue protein, essential for wound healing, which is a primary response to tissue injury. This study explains the role of l-pro on cutaneous wound healing in rats when administered both topically and orally. Open excision wounds were made on the back of rats, and 200 μl (200 mg) of pro was administered topically and orally once daily to the experimental rats until the wounds healed completely. The control wounds were left untreated. Granulation tissues formed were removed after day 4 and 8 of post excision wounding, and biochemical parameters such as total protein, collagen, hexosamine, and uronic acid were estimated. Levels of enzymatic and non-enzymatic antioxidants such as catalase, superoxide dismutase, glutathione peroxidase, ascorbic acid, and reduced glutathione were evaluated along with lipid peroxides in the granulation tissues. Tensile strength and period of epithelialization were also measured. It was observed that the treated wounds healed very fast as evidenced by augmented rates of epithelialization and wound contraction, which was also confirmed by histological examinations. The results strappingly authenticate the beneficial effects of the topical administration of l-proline in the acceleration of wound healing than the oral administration and control.     

Histological manifestations of the sparing effect of cooling in heat dissection of the cerebral cortex and liver]

A new method of heat dissection of tissues combined with application of cooling was studied experimentally in white rats. Histologic changes of tissues of the cerebrum cortex and the liver wounds were investigated. It was found out that automatic selection of temperature regimen in combination of heat and cold ensured stable effect which was well balanced from the point of view of its depth and prevented overheating of tissues surrounding a wound channel. In comparison with cut wounds the above mentioned method allowed to gain better safety of cells.     

Accelerated healing of full-thickness skin wounds in a wet environment

Full-thickness skin wounds are preferably allowed to heal under controlled hydration dressings such as hydrocolloids. It was hypothesized that a wet (liquid) environment rather than a dry or moist one would accelerate the wound healing process. We compared skin repair by secondary intention in full-thickness skin wounds in wet (saline), moist (hydrocolloid), and dry (gauze) conditions in an established porcine wound healing model. The study included three animals with a total of 70 wounds layered in a standardized fashion on the back of young Yorkshire pigs. Twelve days after wounding, 0 percent of dry, 20 percent of moist, and 86 percent of saline-treated wounds were completely reepithelialized (p values = 0.0046 and 0.027 for saline wounds compared with dry and moist wounds, respectively). The accelerated healing was caused at least in part by faster contraction in wet wounds (p value < 0.005 compared with that of other groups 9 and 12 days after wounding). Development of granulation tissue was faster in moist conditions than it was for dry and wet wounds. The thickness and number of cell layers of the newly formed epidermis were greater in dry and wet wounds than in moist ones. It was concluded that these full-thickness porcine skin wounds healed faster in a wet environment than in a moist one. Dry wounds healed more slowly than moist wounds. The basic mechanisms of skin wound repair were influenced by the treatment modality as demonstrated by the observed differences in granulation tissue formation, reepithelialization, and rate of wound contraction.     

Hyaluronan oligosaccharides promote excisional wound healing through enhanced angiogenesis

The biological roles of hyaluronan (HA) fragments in angiogenesis acceleration have been investigated recently. Studies have confirmed that oligosaccharides of HA (o-HA) are capable of stimulating neovascularization in vitro and promoting blood flow or angiogenesis in animal models. However, few laboratories have studied the function of o-HA as an exogenous treatment in injured tissue repair in vivo. It is thought that o-HA may lose its activities when used topically in vivo due to its small size, which may be absorbed quickly by the surrounding tissues. In this study, we prepared a special slow-releasing gel that contains a mixture of defined size of o-HA and studied the healing effects of o-HA by topical application to an acute wound model. We report that o-HA complex promotes the repair of tissue injury of a murine excisional dermal wound. The therapy by o-HA was compared with high molecular weight HA (HMW-HA) and the known angiogenesis stimulator, VEGF. At days 6 to 8 after treatment, significant differences were seen in wound closure rates between o-HA and control or HMW-HA groups, in which o-HA showed an increased wound recovery. Histological analysis revealed that increased neo-blood and lymph vessels were formed in wounded tissues treated by o-HA. In addition, treatments of wounds with o-HA resulted in more granulation production, collagen deposition, and fibroblast proliferation. Analysis of gene expression by real-time RT-PCR demonstrated a significant up-regulation of some cytokines or adhesion molecules in o-HA-treated wounds, which corresponds with the increased granulation tissue in these wounds. Our findings suggested that o-HA therapy may be useful in acute wound repair.     

Role of a microbial factor, necrotic tissue and a foreign body in the development of wound suppuration

The effect of microorganisms, necrotic tissues and a foreign body on the development of festering process in rat wounds was studied. It was found that the presence of necrotic tissues is the necessary and sufficient condition for a clinical manifestation of infection in rat wounds. Additional infection of the wounds and introduction of a foreign body did not appreciably change the clinical picture. A model is suggested of a festering wound in rats without artificial infecting. In the festering wound, one could observe the replacement of the gram-positive coccal microflora by the gram-negative one. Meanwhile the gram-positive coccal microflora was predominant in the non-festering wound. The level of potential biochemical indicators of infection in the blood of animals with festering wounds was higher than in the blood of those with non-festering wounds. The morphology, and the content of microbial cells, the content of nucleic acids, and total proteolytic activity in festering wound tissues were examined over time.     

Curcumin improves wound healing by modulating collagen and decreasing reactive oxygen species

Wound healing consists of an orderly progression of events that re-establish the integrity of the damaged tissue. Several natural products have been shown to accelerate the healing process. The present investigation was undertaken to determine the role of curcumin on changes in collagen characteristics and antioxidant property during cutaneous wound healing in rats. Full-thickness excision wounds were made on the back of rat and curcumin was administered topically. The wound tissues removed on 4th, 8th and 12th day (post-wound) were used to analyse biochemical and pathological changes. Curcumin increased cellular proliferation and collagen synthesis at the wound site, as evidenced by increase in DNA, total protein and type III collagen content of wound tissues. Curcumin treated wounds were found to heal much faster as indicated by improved rates of epithelialisation, wound contraction and increased tensile strength which were also confirmed by histopathological examinations. Curcumin treatment was shown to decrease the levels of lipid peroxides (LPs), while the levels of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), activities were significantly increased exhibiting the antioxidant properties of curcumin in accelerating wound healing. Better maturation and cross linking of collagen were observed in the curcumin treated rats, by increased stability of acid-soluble collagen, aldehyde content, shrinkage temperature and tensile strength. The results clearly substantiate the beneficial effects of the topical application of curcumin in the acceleration of wound healing and its antioxidant effect. Both the authors have contributed equally towards this paper.     

IL-1 plays a critical role in oral, but not dermal, wound healing.

Wound healing is a well-orchestrated complex process leading to the repair of injured tissues. After injury, proinflammatory cytokines act as important modulators of the inflammatory process. IL-1 expression has been regarded as necessary for healing; however, its effects have also been implicated in delayed wound repair. Currently, there is no consensus or direct evidence that IL-1 activity plays a central role in the healing process. The present investigation was undertaken to define the role of IL-1R signaling in the healing outcome of an excisional wound in the palate or scalp of mice that had targeted deletions of the IL-1R type 1 (IL-1R1(-/-)) compared with matched wild-type mice. Histomorphometric analysis was undertaken to assess the degree of healing and the recruitment of polymorphonuclear and mononuclear phagocytes. After 14 days, wild-type mice exhibited complete closure of intraoral wounds, while IL-1R1(-/-) animals had only partial closure (50%). In the IL-1R1(-/-) mice, healing tissues exhibited a persistent inflammatory cell infiltrate, which did not occur in wild-type animals. Treatment with antibiotics significantly diminished the persistent inflammatory infiltrate and improved healing in the experimental animals. In contrast to oral wounds, the rate of healing and recruitment of polymorphonuclear cells in scalp wounds was similar in IL-1R1(-/-) and wild-type mice. The present data underscore the importance of IL-1 in wound healing in a challenging environment and identify its principal role in facilitating the healing process by protecting an open wound from bacterial insult. In a less challenging environment, the production of new connective tissue and its coverage by migrating epithelium are minimally affected by the absence of IL-1 activity.     

Fibronectin involvement in granulation tissue and wound healing in rabbits

This study describes the distribution of fibronectin and its association with reticulin fibers (type III collagen) and hyaluronic acid in shallow rabbit wounds. Linear incisions were made dorsally with a surgical blade. Animals were sacrificed and 1,2,3,4,5, and 8 day wounds were examined using peroxidase-antiperoxidase to localize affinity-purified antibodies to fibronectin. Tissue samples were also stained with hematoxylin and eosin in addition to silver stains for reticulin, and Alcian blue for hyaluronic acid. After wounding, the incision filled with a fibrin clot that stained positively for fibronectin. The underlying dermis and adjacent, unwounded dermis also contained fibronectin. Epidermal cells that migrate from the wound margin between the clot and the dermis were in direct association with fibronectin in these wound components. By 72 hr, epidermal continuity was reestablished. Early granulation tissue formation was apparent just below the epidermis 5 day wounds. Fibronectin was observed in the matrix surrounding individual fibroblasts and codistributed with reticulin fibers and hyaluronic acid in both 5 and 8 day wounds. Granulation tissue of 8 day wounds stained intensely for fibronectin and extended to a greater depth in the reticular dermis. Dense fibrillar networks of fibronectin and fibroblasts were aligned parallel to the epidermis, giving the granulation tissue a highly structured and organized appearance. Fibroblasts contained fibronectin and were surrounded by less fibronectin at the wound periphery than within the granulation tissue. These findings suggest that fibronectin may be important in the reconstruction of tissues during repair by functioning as an extracellular scaffold for migrating cells.     

Improved repair of dermal wounds in mice lacking microRNA‐155

Wound healing is a well-regulated but complex process that involves haemostasis, inflammation, proliferation and maturation. Recent reports suggest that microRNAs (miRs) play important roles in dermal wound healing. In fact, miR deregulation has been linked with impaired wound repair. miR-155 has been shown to be induced by inflammatory mediators and plays a central regulatory role in immune responses. We have investigated the potential role of miR-155 in wound healing. By creating punch wounds in the skin of mice, we found an increased expression of miR-155 in wound tissue when compared with healthy skin. Interestingly, analysis of wounds of mice lacking the expression of miR-155 (miR-155^−/−) revealed an increased wound closure when compared with wild-type animals. Also, the accelerated wound closing correlated with elevated numbers of macrophages in wounded tissue. Gene expression analysis of wounds tissue and macrophages isolated from miR-155^−/− mice that were treated with interleukin-4 demonstrated an increased expression of miR-155 targets (BCL6, RhoA and SHIP1) as well as, the finding in inflammatory zone-1 (FIZZ1) gene, when compared with WT mice. Moreover, the up-regulated levels of FIZZ1 in the wound tissue of miR-155^−/− mice correlated with an increased deposition of type-1 collagens, a phenomenon known to be beneficial in wound closure. Our data indicate that the absence of miR-155 has beneficial effects in the wound healing process.     

Ultrafast Mid-IR Laser Scalpel: Protein Signals of the Fundamental Limits to Minimally Invasive Surgery

Lasers have in principle the capability to cut at the level of a single cell, the fundamental limit to minimally invasive procedures and restructuring biological tissues. To date, this limit has not been achieved due to collateral damage on the macroscale that arises from thermal and shock wave induced collateral damage of surrounding tissue. Here, we report on a novel concept using a specifically designed Picosecond IR Laser (PIRL) that selectively energizes water molecules in the tissue to drive ablation or cutting process faster than thermal exchange of energy and shock wave propagation, without plasma formation or ionizing radiation effects. The targeted laser process imparts the least amount of energy in the remaining tissue without any of the deleterious photochemical or photothermal effects that accompanies other laser wavelengths and pulse parameters. Full thickness incisional and excisional wounds were generated in CD1 mice using the Picosecond IR Laser, a conventional surgical laser (DELight Er:YAG) or mechanical surgical tools. Transmission and scanning electron microscopy showed that the PIRL laser produced minimal tissue ablation with less damage of surrounding tissues than wounds formed using the other modalities. The width of scars formed by wounds made by the PIRL laser were half that of the scars produced using either a conventional surgical laser or a scalpel. Aniline blue staining showed higher levels of collagen in the early stage of the wounds produced using the PIRL laser, suggesting that these wounds mature faster. There were more viable cells extracted from skin using the PIRL laser, suggesting less cellular damage. β-catenin and TGF-β signalling, which are activated during the proliferative phase of wound healing, and whose level of activation correlates with the size of wounds was lower in wounds generated by the PIRL system. Wounds created with the PIRL systsem also showed a lower rate of cell proliferation. Direct comparison of wound healing responses to a conventional surgical laser, and standard mechanical instruments shows far less damage and near absence of scar formation by using PIRL laser. This new laser source appears to have achieved the long held promise of lasers in minimally invasive surgery.     

Spiral computed tomography in the diagnosis of the abdomen gunshot wounds and their complications

The results of studies by spiral computed tomography (SCT) in 62 patients with abdominal wounds were analyzed at the Main Military Clinical Hospital of Internal Forces, Ministry of Internal Affairs of Russia. The main contingent of the wounded included active servicemen who had been wounded in the areas of local conflicts, military men. The studies were conducted on days 2 to 15 of their receiving a wound. The potentialities of the technique in evaluating damages to abdominal organs, retroabdominal space, bony structures, in assessing the topography of foreign bodies are described. SCT was compared with classical X-ray and ultrasound studies, laparocentesis which are traditionally used in the diagnosis of gunshot injury. In the authors' opinion, SCT has become the method of choice in the diagnosis of gunshot injury to the abdomen and its complications today.