Local Tissue Damage Research Articles

In Vivo Neutralization of Myotoxin II, a Phospholipase A2 Homologue from Bothrops asper Venom, Using Peptides Discovered via Phage Display Technology.

Many snake venom toxins cause local tissue damage in prey and victims, which constitutes an important pathology that is challenging to treat with existing antivenoms. One of the notorious toxins that causes such effects is myotoxin II present in the venom of the Central and Northern South American viper, Bothrops asper. This Lys49 PLA2 homologue is devoid of enzymatic activity and causes myotoxicity by disrupting the cell membranes of muscle tissue. To improve envenoming therapy, novel approaches are needed, warranting the discovery and development of inhibitors that target key toxins that are currently difficult to neutralize. Here, we report the identification of a new peptide (JB006), discovered using phage display technology, that is capable of binding to and neutralizing the toxic effects of myotoxin II in vitro and in vivo. Through computational modeling, we further identify hypothetical binding interactions between the toxin and the peptide to enable further development of inhibitors that can neutralize myotoxin II.

Detection of Fibrosis in Cine Magnetic Resonance Images Using Artificial Intelligence Techniques

Background: Artificial intelligence techniques have demonstrated great potential in cardiology, especially to detect imperceptible patterns for the human eye. In this sense, these techniques seem to be adequate to identify patterns in the myocardial texture which could lead to characterize and quantify fibrosis. Purpose: The aim of this study was to postulate a new artificial intelligence method to identify fibrosis in cine cardiac magnetic resonance (CMR) imaging. Methods: A retrospective observational study was carried out in a population of 75 subjects from a clinical center of San Carlos de Bariloche. The proposed method analyzes the myocardial texture in cine CMR images using a convolutional neural network to determine local myocardial tissue damage. Results: An accuracy of 89% for quantifying local tissue damage was observed for the validation data set and 70% for the test set. In addition, the qualitative analysis showed a high spatial correlation in lesion location. Conclusions: The postulated method enables to spatially identify fibrosis using only the information from cine nuclear magnetic resonance studies, demonstrating the potential of this technique to quantify myocardial viability in the future or to study the lesions etiology

Immersion optical clearing of adipose tissue in rats: ex vivo and in vivo studies.

Optical clearing (OC) of adipose tissue has not been studied enough, although it can be promising in medical applications, including surgery and cosmetology, for example, to visualize blood vessels or increase the permeability of tissues to laser beams. The main objective of this work is to develop technology for OC of abdominal adipose tissue in vivo using hyperosmotic optical clearing agents (OCAs). The maximum OC effect (77%) was observed for ex vivo rat adipose tissue samples exposed to OCA on fructose basis for 90 minutes. For in vivo studies, the maximum effect of OC (65%) was observed when using OCA based on diatrizoic acid and dimethylsulfoxide for 120 minutes. Histological analysis showed that in vivo application of OCAs may induce a limited local necrosis of fat cells. The efficiency of OC correlated with local tissue damage through cell necrosis due to accompanied cell lipolysis.

Quantifying the magnitude of local tendon injury from electrosurgical transection.

Electrocautery is a common surgical technique and is often used during shoulder arthroplasty to elevate or transect the subscapularis tendon. The relative amount of tissue damage caused by cautery as opposed to sharp transection is not currently known. The purpose of this study was to examine local tissue damage resulting from electrocautery vs. sharp transection with a scalpel. We hypothesized that the electrosurgical unit would cause higher collateral tissue damage and cell death compared with sharp transection. Twelve cadaveric ovine shoulders were randomized to either the electrosurgical or sharp transection group. The infraspinatus tendon was isolated, and a partial-thickness transection was made using either a monopolar electrosurgical device (Bovie) or No. 10 scalpel blade. Tendon explants were then visualized with confocal microscopy to evaluate tissue architecture. A live/dead assay was performed using microscopy imaging analysis software. Comparisons between Bovie and scalpel transection were made using the Mann-Whitney U test, and the cell death percentage at standardized distances from the transection site was compared between groups using a mixed-model analysis. Significance was defined at P < .05. The cellular and tendon fibril architecture was well maintained beyond the scalpel transection site, whereas Bovie transection disrupted the architecture beyond its transection path. The percentage of dead cells in the Bovie group (74.9% ± 31.2%) was significantly higher than that in the scalpel group (27.6% ± 29.9%, P = .0004). Compared with the transection site, the cell death percentage after Bovie transection significantly declined at 2.5 mm whereas that after scalpel transection significantly declined at 1 mm from the transection site. There was a significantly higher dead cell percentage in the Bovie transection group, indicating extensive damage beyond the local incision site, compared with sharp transection. Electrosurgical transection of the ovine infraspinatus tendon exvivo caused higher cell death and greater tissue architecture disruption compared with sharp scalpel transection.

Fusion of Normoxic- and Hypoxic-Preconditioned Myoblasts Leads to Increased Hypertrophy.

Injuries, high altitude, and endurance exercise lead to hypoxic conditions in skeletal muscle and sometimes to hypoxia-induced local tissue damage. Thus, regenerative myoblasts/satellite cells are exposed to different levels and durations of partial oxygen pressure depending on the spatial distance from the blood vessels. To date, it is unclear how hypoxia affects myoblasts proliferation, differentiation, and particularly fusion with normoxic myoblasts. To study this, we investigated how 21% and 2% oxygen affects C2C12 myoblast morphology, proliferation, and myogenic differentiation and evaluated the fusion of normoxic- or hypoxic-preconditioned C2C12 cells in 21% or 2% oxygen in vitro. Out data show that the long-term hypoxic culture condition does not affect the proliferation of C2C12 cells but leads to rounder cells and reduced myotube formation when compared with myoblasts exposed to normoxia. However, when normoxic- and hypoxic-preconditioned myoblasts were differentiated together, the resultant myotubes were significantly larger than the control myotubes. Whole transcriptome sequencing analysis revealed several novel candidate genes that are differentially regulated during the differentiation under normoxia and hypoxia in mixed culture conditions and may thus be involved in the increase in myotube size. Taken together, oxygen-dependent adaption and interaction of myoblasts may represent a novel approach for the development of innovative therapeutic targets.

Research on Mechanical–Structural and Oil Yield Properties during Xanthoceras sorbifolium Seed Oil Extraction

Products from Xanthoceras sorbifolium Bunge seed have gained extensive attention for various applications, especially in the fields of edible oils and industrial applications. In order to study seed kernel mechanical–structural behavior and oil yield mechanisms during extrusion, we set up a self-developed texture analyzer with in situ microscope observation. Test results indicated that seed kernel oil yield and pressing energy showed an approximately parabolic shape under pressing strain, and maximum oil yield reached 25.7%. Only local tissue damage occurred on seed kernels at strain 45–85%, cracks formed from the kernel edge to the inside zone and small cracks obviously increased in number, corresponding with the oil yield and energy–strain curve. The effect of speed on oil yield showed an opposite trend to strain effect; high pressing speed led to lower oil yield due to the short time for oil precipitation and lower pressing energy. Dwell time obviously promoted oil output within 600 s. Drying temperature had a negative effect due to structural change. Oil yield was almost zero at temperatures below 120 °C. The oil yield and pressing energy relation curve was obtained by polynomial fitting; optimal seed kernel oil pressing conditions were strain 95%, 0.1 mm/s, 20 °C, dwell time 600 s. The research provides in-depth theoretical guidance for Xanthoceras sorbifolium Bunge oil production.

TRUE-1: Trial of Repurposed Unithiol for snakebite Envenoming phase 1 (safety, tolerability, pharmacokinetics and pharmacodynamics in healthy Kenyan adults).

Background: Snakebites affect over 5 million people each year, and over 100,000 per year die as a result. The only available treatment is antivenom, which has many shortcomings including high cost, intravenous administration, and high risk of adverse events. One of the most abundant and harmful components of viper venoms are the zinc-dependent snake venom metalloproteinases (SVMPs). Unithiol is a chelating agent which is routinely used to treat heavy metal poisoning. In vivo experiments in small animal models have demonstrated that unithiol can prevent local tissue damage and death caused by a certain viper species. This phase I clinical trial will assess the safety of ascending doses of unithiol with a view for repurposing for snakebite indication. Methods: This open label, single agent, phase I clinical trial of a repurposed drug has a primary objective to evaluate the safety of escalating doses of unithiol, and a secondary objective to describe its pharmacokinetics. In total, 64 healthy Kenyan volunteers from Kilifi County will be dosed in consecutive groups of eight, with dose escalation decisions dependent on review of safety data by an independent data safety monitoring board. Four groups will receive ascending single oral doses, two will receive multiple oral doses, and two will receive single intravenous doses. Follow-up will be for 6-months and includes full adverse event reporting. Pharmacokinetic analysis will define the Cmax, Tmax, half-life and renal elimination. Conclusions: This clinical trial will assess the safety and tolerability of a promising oral therapeutic in a relevant setting where snakebites are prevalent. Unithiol is likely to be safer than antivenom, is easier to manufacture, has activity against diverse snake species, and can be administered orally, and thus shows promise for repurposing for tropical snakebite. Pan African Clinical Trials Registry: PACTR202103718625048 (3/3/2021).

Cross-Communication Between Knee Osteoarthritis and Fibrosis: Molecular Pathways and Key Molecules.

Knee fibrosis is characterized by the presence of excessive connective tissue due to dysregulated fibroblast activation following local or systemic tissue damage. Knee fibrosis constitutes a major clinical problem in orthopaedics due to the severe limitation in the knee range of motion that leads to compromised function and patient disability. Knee osteoarthritis is an extremely common orthopedic condition that is associated with patient disability and major costs to the health-care systems worldwide. Although knee fibrosis and osteoarthritis (OA) have traditionally been perceived as two separate pathologic entities, recent research has shown common ground between the pathophysiologic processes that lead to the development of these two conditions. The purpose of this review was to identify the pathophysiologic pathways as well as key molecules that are implicated in the development of both knee OA and knee fibrosis in order to understand the relationship between the two diagnoses and potentially identify novel therapeutic targets.

Microscale concert hall acoustics to produce uniform ultrasound stimulation for targeted sonogenetics in hsTRPA1-transfected cells.

The field of ultrasound neuromodulation has rapidly developed over the past decade, a consequence of the discovery of strain-sensitive structures in the membrane and organelles of cells extending into the brain, heart, and other organs. Notably, clinical trials are underway for treating epilepsy using focused ultrasound to elicit an organized local electrical response. A key limitation to this approach is the formation of standing waves within the skull. In standing acoustic waves, the maximum ultrasound intensity spatially varies from near zero to double the mean in one half a wavelength, and has lead to localized tissue damage and disruption of normal brain function while attempting to evoke a broader response. This phenomenon also produces a large spatial variation in the actual ultrasound exposure in tissue, leading to heterogeneous results and challenges with interpreting these effects. One approach to overcome this limitation is presented herein: transducer-mounted diffusers that result in spatiotemporally incoherent ultrasound. Herein, we numerically and experimentally quantified the effect of a diffuser in an enclosed domain, and show that adding the diffuser leads to a two-fold increase in ultrasound responsiveness of hsTRPA1 transfected HEK cells. Furthermore, we demonstrate the diffuser allow us to produce an uniform spatial distribution of pressure in the rodent skull. Collectively, we propose that our approach leads to a means to deliver uniform ultrasound into irregular cavities for sonogenetics.

I\u03baB-\u03b6 signaling promotes chondrocyte inflammatory phenotype, senescence, and erosive joint pathology

Osteoarthritis is a joint disease characterized by a poorly-defined inflammatory response that does not encompass a massive immune cell infiltration yet contributes to cartilage degradation and loss of joint mobility, suggesting a chondrocyte intrinsic inflammatory response. Using primary chondrocytes from joints of osteoarthritic mice and patients, we first show that these cells express ample pro-inflammatory markers and RANKL in an NF-κB dependent manner. The inflammatory phenotype of chondrocytes was recapitulated by exposure of chondrocytes to IL-1β and bone particles, which were used to model bone matrix breakdown products revealed to be present in synovial fluid of OA patients, albeit their role was not defined. We further show that bone particles and IL-1β can promote senescent and apoptotic changes in primary chondrocytes due to oxidative stress from various cellular sources such as the mitochondria. Finally, we provide evidence that inflammation, oxidative stress and senescence converge upon IκB-ζ, the principal mediator downstream of NF-κB, which regulates expression of RANKL, inflammatory, catabolic, and SASP genes. Overall, this work highlights the capacity and mechanisms by which inflammatory cues, primarily joint degradation products, i.e., bone matrix particles in concert with IL-1β in the joint microenvironment, program chondrocytes into an “inflammatory phenotype” which inflects local tissue damage.

Protective role of the nucleic acid sensor STING in idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is the most common type of interstitial lung disease, characterized by progressive lung scarring and a high mortality rate. IPF has no cure and available treatments at best delay disease progression. IPF is largely driven by host-derived danger signals released upon recurrent local tissue damage. We explore the roles of self-DNA and the intracellular DNA sensor stimulator interferon genes (STING), which activation leads to type I/III interferons (IFN) production and autophagy induction. We used the classical model of IPF by intranasal administration of bleomcyin (BLM) (7.5 and 3 mg/kg for day 1 and day 14 experiments, respectively ; Bellon Laboratories). C57BL/6 J wild type (WT) adult (8–14-week old) males were used, together with mice deficient for STING (Sting -/− ), cGas -/− and type I interferon (IFN) receptor (Ifnar1 -/− ). We report that STING deficiency leads to exacerbated pulmonary fibrosis with increased lung collagen deposition and excessive remodeling factors expression. We show that STING-mediated protection does not rely on type I IFN signaling nor IL-17A or TGF-β modulation. Interestingly, we observed persistent airway neutrophilia and decreased type III IFN (IL-28) in lung tissues of BLM-treated Sting -/− mice in comparison to their WT counterparts. We hypothesize that STING may limit neutrophilic inflammation through IL-28 signaling, downregulating subsequent adaptive immunity, remodeling and fibrosis. In addition, STING displays important anti-inflammatory properties through its phylogenetically conserved autophagy-inducing pathway. Autophagy favors collagen degradation and mouse survival in experimental lung fibrosis and autophagy-related proteins are decreased in IPF patients. Interestingly, our first results show that lung expression of autophagy related proteins ATG5, P62 and LC3B-II is reduced in BLM-treated Sting -/− mice in comparison to their WT relatives, indicating that BLM-induced autophagy depends on STING. Together, our data support an unprecedented immunoregulatory function of STING in lung fibrosis that may rely on STING-dependent IL-28 and/or autophagy.

Molecular Architecture of the Antiophidic Protein DM64 and its Binding Specificity to Myotoxin II From Bothrops asper Venom.

DM64 is a toxin-neutralizing serum glycoprotein isolated from Didelphis aurita, an ophiophagous marsupial naturally resistant to snake envenomation. This 64 kDa antitoxin targets myotoxic phospholipases A2, which account for most local tissue damage of viperid snakebites. We investigated the noncovalent complex formed between native DM64 and myotoxin II, a myotoxic phospholipase-like protein from Bothrops asper venom. Analytical ultracentrifugation (AUC) and size exclusion chromatography indicated that DM64 is monomeric in solution and binds equimolar amounts of the toxin. Attempts to crystallize native DM64 for X-ray diffraction were unsuccessful. Obtaining recombinant protein to pursue structural studies was also challenging. Classical molecular modeling techniques were impaired by the lack of templates with more than 25% sequence identity with DM64. An integrative structural biology approach was then applied to generate a three-dimensional model of the inhibitor bound to myotoxin II. I-TASSER individually modeled the five immunoglobulin-like domains of DM64. Distance constraints generated by cross-linking mass spectrometry of the complex guided the docking of DM64 domains to the crystal structure of myotoxin II, using Rosetta. AUC, small-angle X-ray scattering (SAXS), molecular modeling, and molecular dynamics simulations indicated that the DM64-myotoxin II complex is structured, shows flexibility, and has an anisotropic shape. Inter-protein cross-links and limited hydrolysis analyses shed light on the inhibitor’s regions involved with toxin interaction, revealing the critical participation of the first, third, and fifth domains of DM64. Our data showed that the fifth domain of DM64 binds to myotoxin II amino-terminal and beta-wing regions. The third domain of the inhibitor acts in a complementary way to the fifth domain. Their binding to these toxin regions presumably precludes dimerization, thus interfering with toxicity, which is related to the quaternary structure of the toxin. The first domain of DM64 interacts with the functional site of the toxin putatively associated with membrane anchorage. We propose that both mechanisms concur to inhibit myotoxin II toxicity by DM64 binding. The present topological characterization of this toxin-antitoxin complex constitutes an essential step toward the rational design of novel peptide-based antivenom therapies targeting snake venom myotoxins.

Ідентифікація нейропатичного компонента болю в пацієнтів з остеоартрозом колінних суглобів

Біль при остеоартрозі є результатом стимуляції ноцицепторів і виникає внаслідок тканинного пошкодження та локального запалення. Останні дані вказують на наявність симптомів нейропатичного болю в пацієнтів з остеоартрозом. Мета дослідження: з’ясувати структуру больового синдрому та виявити наявність нейропатичного компонента болю. Матеріали і методи. Було обстежено 37 пацієнтів з остеоартрозом колінних суглобів ІІ–ІІІ стадії за Kallgren — Lawrence. Для виявлення нейропатичного компонента болю використовували скринінгові шкали нейропатичного болю — painDETECT, LANSS, DN4. Додатково пацієнтів опитували за візуальною аналоговою шкалою, WOMAC та EuroQol-5D. Результати. Згідно з опитувальником painDETECT нейропатичний компонент болю в пацієнтів з остеоартрозом колінних суглобів виявлено у 5,4 % обстежених, за LANSS — у 29,7 % та за DN4 — у 35,1 %. Встановлено вірогідні помірні кореляційні зв’язки з інтенсивністю больового синдрому та результатами анкетування за скринінговими шкалами (painDETECT, LANSS, DN4) (p &lt; 0,05). Також виявлено, що вищі результати анкетування за painDETECT та DN4 позитивно корелювали з порушенням щоденної активності, оціненої за допомогою WOMAC (p &lt; 0,05). Дані рainDETECT мали позитивний зв’язок з опитувальником EuroQol-5D (p &lt; 0,01).

Microbial Translocation and Perinatal Asphyxia/Hypoxia: A Systematic Review.

The microbiome is vital for the proper function of the gastrointestinal tract (GIT) and the maintenance of overall wellbeing. Gut ischemia may lead to disruption of the intestinal mucosal barrier, resulting in bacterial translocation. In this systematic review, according to PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analysis) guidelines, we constructed a search query using the PICOT (Patient, Intervention, Comparison, Outcome, Time) framework. Eligible studies reported in PubMed, up to April 2021 were selected, from which, 57 publications’ data were included. According to these, escape of intraluminal potentially harmful factors into the systemic circulation and their transmission to distant organs and tissues, in utero, at birth, or immediately after, can be caused by reduced blood oxygenation. Various factors are involved in this situation. The GIT is a target organ, with high sensitivity to ischemia–hypoxia, and even short periods of ischemia may cause significant local tissue damage. Fetal hypoxia and perinatal asphyxia reduce bowel motility, especially in preterm neonates. Despite the fact that microbiome arouse the interest of scientists in recent decades, the pathophysiologic patterns which mediate in perinatal hypoxia/asphyxia conditions and gut function have not yet been well understood.

The Natural Ligand for Metalloproteinase-A Multifaceted Drug Target.

Metalloproteinase is one of the key components of Russell viper venom and it is the root cause of edema, blood coagulation, local tissue damage, hemorrhage, and inflammation during snakebite envenoming. Hence, finding a suitable metalloproteinase inhibitor from natural source will be of great biological importance in mitigating pathological effects. In this current study, we employed computational analysis to examine the inhibition of metalloproteinase by phytochemicals present in Andrographis paniculata. Molecular docking studies revealed interaction of A. paniculata phytochemicals with the catalytic M domain's active site amino acid residues, namely ASN203, ARG293, PHE203, LEU206, LYS199, and ALA122, similar to that of the reference compound Batimastat. 14-acetylandrographolide, 14-deoxy-11,12 didehydroandrographolide, Andrograpanin, Isoandrographolide, and 14-deoxy-11-oxoandrographolide displayed high binding energy and inhibition against the metalloproteinase. Molecular dynamic simulation analysis revealed less root mean square fluctuation of amino acid residues of metalloproteinase-14-acetylandrographolide complex than metalloproteinase-Batimastat complex indicating the high stability for metalloproteinase with the phytochemical. In silico analysis of parameters like ADME properties and drug-likeness of the phytochemicals exhibited good pharmacokinetic properties. Ligand-based virtual screening of phytochemicals to identify similarity to FDA-approved drugs and identification of their possible targets were also performed. The outcome of the current study strengthens the significance of these phytochemicals as promising lead candidates for the treatment of snakebite envenomation. Moreover, the study also encourages the in vivo and in vitro evaluation of the phytochemicals to validate the computational findings.

Ethnomedicinal plants and isolated compounds against Snake venom activity: A review

Snakebite is an occupational hazard that has affected the population in tropical and subtropical countries. Worldwide approximately 5.4 million bites, 2.7 million envenomations, and 81,000-1,38,000 deaths are observed per annum. The incidences are higher among farmers and plantation workers. Antivenom is the only treatment available and the production of the same is challenging due to geographical variation of snakes, storage conditions, and non-availability of venom for production. Antivenom therapy is associated with immediate or delayed hypersensitivity and does not prevent local tissue damage. Thus the search for medicinal plants by the scientific community has become relevant. The ethnobotanical studies on various plants have revealed their use to treat various ailments including snakebite. Hence, the review is aimed to amass the medicinal plants studied and also emphasize various components isolated that have shown promising results.

INTENSITY OF FREE RADICAL PROCESSES IN THE POSTNUCLEAR FRACTION OF RAT KIDNEYS UNDER INFLUENCE OF LASER IRRADIATION AND ω-3 POLYUNSATURATED FATTY ACIDS

Introduction. The effect of laser irradiation on the body can lead to local tissue damage, which will be accompanied by changes in biochemical processes that occur in the kidneys. The direction of these changes is completely unclear, so the study of free radical oxidation of lipids and proteins as the main markers of oxidative stress in the body and their correction by ω-3 polyunsaturated fatty acids (PUFA) remains relevant. Aim. To evaluate the intensity of lipid peroxidation and oxidative modification of proteins in the postnuclear fraction of rat kidneys under the action of laser irradiation and additional administration of ω-3 PUFA. Methods. The studies used white outbred rats, which were irradiated daily for 4 minutes with a laser diode with a wavelength of 650 nm, power of 50 mW in the abdominal cavity at a distance of 10 cm from the skin surface. The state of lipid peroxidation (LPO) was determined by the level of primary, secondary and final products. The intensity of oxidative modification of proteins (OMP) was evaluated by the level of carbonyl derivatives and protein SH-groups. To correct the prooxidant state, the animals were additionally injected with ω-3 PUFA. Results. Low-intensity laser irradiation has a destructive effect on the cell membranes of the kidneys, which is expressed by an increase in primary, secondary and final products of LPO in phospholipid extracts and an increase in the intensity of OMP. The introduction of ω-3 PUFAs reduces free radical processes in the kidneys of irradiated rats, but this effect depends on the scheme of their introduction. ω-3 PUFAs do not show antioxidant effect under the conditions of their introduction after laser irradiation. Daily administration of ω-3 PUFA two hours before irradiation shows a slight antioxidant effect only in the initial stages of irradiation. Preliminary seven-day administration of ω-3 PUFA before laser irradiation is the most effective, as it helps to reduce free radical processes. Conclusion. It is established that ω-3 PUFAs are able to have a corrective effect on the action of low-intensity laser irradiation, which depends on the scheme of their introduction. The highest antioxidant effect is observed in groups of animals to which ω-3 PUFA was previously administered before the action of laser irradiation.

Skin Graft Versus Local Flaps in Management of Post-burn Elbow Contracture.

IntroductionContracture is a pathological scar tissue resulting from local skin tissue damage, secondary to different local factors. It can restrict joint mobility, resulting in deformity and disability. This study aimed to investigate the outcomes of skin grafts compared to local flaps to reconstruct post-burn elbow contractures. These parameters included regaining function, range of movement, recurrence, and local wound complications.MethodologyA retrospective study reviewed 21 patients for elbow reconstruction over 12 months. Only patients with post-burn elbow contracture were included. Other causes, including previous corrective surgery, associated elbow stiffness, and patients who opted out of post-operative physiotherapy, were excluded. Patients were categorized according to the method of coverage into three groups: graft alone (G1), local flap (G2), or combined approach (G3). ResultsFemales were three times at higher risk to suffer a burn injury, while almost half of the cases were children. Scald injury represented 81% of burn causes. G1,2,3 were used in 47.6%, 42.9% and 9.5% of cases retrospectively. The overall rate of infection was 28.6%. Hundred percent graft taken was recorded in 83.3 % of cases; however, flap take was 91.1%. After 12 months of follow-up, re-contracture was 60% and 22.8% in G1 and G2; however, the satisfaction rate was 70% and 100% in both groups retrospectively. The overall satisfaction was 85.7% in all groups.ConclusionGrafts and local flaps are reasonable options for post contracture release; however, flaps are superior. Coverage selection depends on the lost tissue area and exposure of underlying deep structures. Physiotherapy and patient satisfaction are crucial in the outcomes.

A fingerprint of plasma proteome alteration after local tissue damage induced by Bothrops leucurus snake venom in mice

Bothrops spp. is responsible for about 70% of snakebites in Brazil, causing a diverse and complex pathophysiological condition. Bothrops leucurus is the main species of medical relevance found in the Atlantic coast in the Brazilian Northeast region. The pathophysiological effects involved B. leucurus snakebite as well as the organism's reaction in response to this envenoming, it has not been explored yet. Thus, edema was induced in mice paw using 1.2, 2.5, and 5.0 μg of B. leucurus venom, the percentage of edema was measured 30 min after injection and the blood plasma was collected and analyzed by shotgun proteomic strategy. We identified 80 common plasma proteins with differential abundance among the experimental groups and we can understand the early aspects of this snake envenomation, regardless of the suggestive severity of an ophidian accident. The results showed B. leucurus venom triggers a thromboinflammation scenario where family's proteins of the Serpins, Apolipoproteins, Complement factors and Component subunits, Cathepsins, Kinases, Oxidoreductases, Proteases inhibitors, Proteases, Collagens, Growth factors are related to inflammation, complement and coagulation systems, modulators platelets and neutrophils, lipid and retinoid metabolism, oxidative stress and tissue repair. Our findings set precedents for future studies in the area of early diagnosis and/or treatment of snakebites. SignificanceThe physiopathological effects that the snake venoms can cause have been investigated through classical and reductionist tools, which allowed, so far, the identification of action mechanisms of individual components associated with specific tissue damage. The currently incomplete limitations of this knowledge must be expanded through new approaches, such as proteomics, which may represent a big leap in understanding the venom-modulated pathological process. The exploration of the complete protein set that suffer modifications by the simultaneous action of multiple toxins, provides a map of the establishment of physiopathological phenotypes, which favors the identification of multiple toxin targets, that may or may not act in synergy, as well as favoring the discovery of biomarkers and therapeutic targets for manifestations that are not neutralized by the antivenom.

Pharmacokinetic study of the novel phosphocholine derivative 3-dibutylaminopropylphosphonic acid by LC-MS coupling

CRP is an important mediator of the inflammatory response. Pro-inflammatory CRP effects are mediated by pCRP* and mCRP, dissociation products of the native pCRP. The concentration of pCRP during inflammation may rise up to concentrations 1000-fold from baseline. By prevention of the conformational change from pCRP to pCRP*, pro-inflammatory immune responses can be inhibited and local tissue damage reduced. 3-(Dibutylamino)propylphosphonic acid (C10m) is a new substance that can suppress ischemic-reperfusion injury by targeting CRP in the complement cascade. It hampers dissociation of pCRP into its monomers, thus preventing exacerbation of tissue inflammation subsequent to reperfusion injury. In this study, the pharmacokinetics and metabolism of the new drug candidate C10m was investigated. A sensitive and selective method for detection of C10m and its metabolites from plasma and urine was developed with LC-MS and LC-MS/MS coupling. The LLOQ is at 0.1 µg mL−1 and recovery at 87.4% ± 2.8%. Accuracy and precision were within 15% coefficient of variation and nominal concentrations, respectively. Concentration time profile after i.v. bolus injection of C10m was analyzed by LC-MS/MS. Bioavailability has shown to be below 30%. Most likely due to the compounds’ very polar chemical properties, no phase-I or phase-II metabolism could be observed. Absence of phase-I metabolism was cross-checked by performing microsomal incubations. Our study revealed that C10m is rapidly eliminated via urine excretion and that half-times appear to be increased with coadministration of the target pCRP.