Physiological Repair Research Articles

Tumour necrosis factor-like weak inducer of apoptosis (TWEAK) in kidney disease: a biomarker or therapeutic target?

Kidney disease is a significant public health problem that is increasing worldwide. Tumour necrosis factor superfamily molecules have recently been shown to be actively involved in renal pathophysiology. According to current reports, one of these molecules has significant clinical implications: TWEAK, a tumour necrosis factor-like weak inducer of apoptosis. TWEAK is a cytokine with important functions. By binding to induced fibroblast growth factor 14 (Fn14), its only receptor, TWEAK activates various biological processes, including cell growth, migration or death, angiogenesis and production of proinflammatory cytokines. TWEAK and Fn14 expression is relatively low in healthy tissues. Experimental studies have confirmed the important role of TWEAK/Fn14 pathway activation in physiological tissue repair and regeneration, while its excessive activation leads to acute and/or chronic damage. TWEAK production takes place in various inflammatory diseases of the kidneys with the participation of immune cells. In the case of inflammatory diseases characterised by increased chemokine production, TWEAK presents with apoptotic effects. In non-immune diseases, TWEAK stimulates renal tubular proliferation. The dualism of the TWEAK effect is multifactorial. TWEAK was proliferative in healthy kidneys and in a compensatory overgrowth model after nephrectomy in which inflammatory cytokine expression was low. Data obtained from experimental and clinical studies are useful for developing future diagnostic and therapeutic strategies focused on the role of TWEAK in kidney damage.

Proteomics of Extracellular Vesicles: Update on Their Composition, Biological Roles and Potential Use as Diagnostic Tools in Atherosclerotic Cardiovascular Diseases

Extracellular vesicles (EVs) are lipid-bound vesicles released from cells under physiological and pathological conditions. Basing on biogenesis, dimension, content and route of secretion, they can be classified into exosomes, microvesicles (MVs) and apoptotic bodies. EVs have a key role as bioactive mediators in intercellular communication, but they are also involved in other physiological processes like immune response, blood coagulation, and tissue repair. The interest in studying EVs has increased over the years due to their involvement in several diseases, such as cardiovascular diseases (CVDs), and their potential role as biomarkers in diagnosis, therapy, and in drug delivery system development. Nowadays, the improvement of mass spectrometry (MS)-based techniques allows the characterization of the EV protein composition to deeply understand their role in several diseases. In this review, a critical overview is provided on the EV’s origin and physical properties, as well as their emerging functional role in both physiological and disease conditions, focusing attention on the role of exosomes in CVDs. The most important cardiac exosome proteomic studies will be discussed giving a qualitative and quantitative characterization of the exosomal proteins that could be used in future as new potential diagnostic markers or targets for specific therapies.

Cardiac Resynchronization Therapy Pacemaker and Double Valve Replacements Improved Cardiac Function after Physiological Repair in a Patient with Congenitally Corrected Transposition of the Great Arteries

Cardiac Resynchronization Therapy Pacemaker and Double Valve Replacements Improved Cardiac Function after Physiological Repair in a Patient with Congenitally Corrected Transposition of the Great Arteries

Gastric Stem Cells: Physiological and Pathological Perspectives.

Gastric epithelium operates in a hazardous environment that curtails the lifespan of the constituent cells, imposing a requirement for continuous epithelial renewal. Stem cells that reside in the stomach are thus essential for regulating physiological tissue renewal and injury repair because of their self-renewal, high proliferation capacity and multiple differentiation potentials. Recent investigations using lineage tracing models have identified diverse populations of gastric stem cells and even fully differentiated cells that can regain stem cell capacity, so enriching our understanding on the identity and plasticity of gastric stem cells. These cell populations include the Villin promotor, Lgr5+, CCKR2+, Axin2+ and AQP5+ stem cells in the antrum, TFF2 mRNA, Mist1+ cells and Troy+ mature chief cells in the corpus, as well as Sox2, eR1, Lrig1, Bmi1-marked cell in both the antrum and the corpus. Establishment of gastric organoids derived from primary gastric tissues and pluripotent stem cells or embryonic stem cells characterizes niche factors required by the gastric stem cell populations, and further provides new insights into stomach development, host-Helicobacter pylori interactions and malignant transformation. Furthermore, focus on the gastric stem cells and their niches uncovers the initiation of stomach precancerous lesions and origin of gastric cancer, providing options for cancer prevention and intervention. In summary, with the development of stem cell research, gastric stem cells give us more opportunities to prevent and treat stomach diseases.

The Beneficial Roles of SIRT1 in Neuroinflammation-Related Diseases.

Sirtuins are the class III of histone deacetylases whose deacetylate of histones is dependent on nicotinamide adenine dinucleotide (NAD+). Among seven sirtuins, SIRT1 plays a critical role in modulating a wide range of physiological processes, including apoptosis, DNA repair, inflammatory response, metabolism, cancer, and stress. Neuroinflammation is associated with many neurological diseases, including ischemic stroke, bacterial infections, traumatic brain injury, Alzheimer's disease (AD), and Parkinson's disease (PD). Recently, numerous studies indicate the protective effects of SIRT1 in neuroinflammation-related diseases. Here, we review the latest progress regarding the anti-inflammatory and neuroprotective effects of SIRT1. First, we introduce the structure, catalytic mechanism, and functions of SIRT1. Next, we discuss the molecular mechanisms of SIRT1 in the regulation of neuroinflammation. Finally, we analyze the mechanisms and effects of SIRT1 in several common neuroinflammation-associated diseases, such as cerebral ischemia, traumatic brain injury, spinal cord injury, AD, and PD. Taken together, this information implies that SIRT1 may serve as a promising therapeutic target for the treatment of neuroinflammation-associated disorders.

DNA-PKcs phosphorylation at the T2609 cluster alters the repair pathway choice during immunoglobulin class switch recombination

The DNA-dependent protein kinase (DNA-PK), which is composed of the KU heterodimer and the large catalytic subunit (DNA-PKcs), is a classical nonhomologous end-joining (cNHEJ) factor. Naïve B cells undergo class switch recombination (CSR) to generate antibodies with different isotypes by joining two DNA double-strand breaks at different switching regions via the cNHEJ pathway. DNA-PK and the cNHEJ pathway play important roles in the DNA repair phase of CSR. To initiate cNHEJ, KU binds to DNA ends and recruits and activates DNA-PK. Activated DNA-PK phosphorylates DNA-PKcs at the S2056 and T2609 clusters. Loss of T2609 cluster phosphorylation increases radiation sensitivity but whether T2609 phosphorylation has a role in physiological DNA repair remains elusive. Using the DNA-PKcs5A mouse model carrying alanine substitutions at the T2609 cluster, here we show that loss of T2609 phosphorylation of DNA-PKcs does not affect the CSR efficiency. Yet, the CSR junctions recovered from DNA-PKcs5A/5A B cells reveal increased chromosomal translocations, extensive use of distal switch regions (consistent with end resection), and preferential usage of microhomology-all signs of the alternative end-joining pathway. Thus, these results uncover a role of DNA-PKcs T2609 phosphorylation in promoting cNHEJ repair pathway choice during CSR.

Oxidative cross-linking of fibronectin confers protease resistance and inhibits cellular migration.

The oxidation of tyrosine residues to generate o,o'-dityrosine cross-links in extracellular proteins is necessary for the proper function of the extracellular matrix (ECM) in various contexts in invertebrates. Tyrosine oxidation is also required for the biosynthesis of thyroid hormone in vertebrates, and there is evidence for oxidative cross-linking reactions occurring in extracellular proteins secreted by myofibroblasts. The ECM protein fibronectin circulates in the blood as a globular protein that dimerizes through disulfide bridges generated by cysteine oxidation. We found that cellular (fibrillar) fibronectin on the surface of transforming growth factor-β1 (TGF-β1)-activated human myofibroblasts underwent multimerization by o,o'-dityrosine cross-linking under reducing conditions that disrupt disulfide bridges, but soluble fibronectin did not. This reaction on tyrosine residues required both the TGF-β1-dependent production of hydrogen peroxide and the presence of myeloperoxidase (MPO) derived from inflammatory cells, which are active participants in wound healing and fibrogenic processes. Oxidative cross-linking of matrix fibronectin attenuated both epithelial and fibroblast migration and conferred resistance to proteolysis by multiple proteases. The abundance of circulating o,o'-dityrosine-modified fibronectin was increased in a murine model of lung fibrosis and in human subjects with interstitial lung disease compared to that in control healthy subjects. These studies indicate that tyrosine can undergo stable, covalent linkages in fibrillar fibronectin under inflammatory conditions and that this modification affects the migratory behavior of cells on such modified matrices, suggesting that this modification may play a role in both physiologic and pathophysiologic tissue repair.

The Relationship Between Changes In Sleep, Inflammatory Biomarkers, And Energy Expenditure In Female Soccer Players

The chronic stress of training and frequent travel during the competitive soccer season may adversely affect sleep and thus, recovery in collegiate athletes. PURPOSE: To examine the relationship between changes in sleep, inflammatory biomarkers, and exercise energy expenditure (EEE) throughout the season. METHODS: DI female soccer players (N=24) were monitored throughout the competitive season. During all training and games, EEE (kcal/kg) was evaluated using an integrative GPS and heart rate monitoring system, which was individualized based on pre-season performance testing. Pittsburgh Sleep Quality Index (PSQI) questionnaires, weight assessments, and blood draws were completed prior to preseason and at weeks 2, 4, 8, & 12 of the season. Total cortisol (TCORT), free cortisol (FCORT), c-reactive protein (CRP), IL-6, and TNFα were analyzed. Change scores were calculated between timepoints for each biomarker, GlobalPSQI, Sleep Duration (SD), and Sleep Quality (SQ) scores. Pearson product correlations were conducted between change scores as well as EEEAVG between timepoints with significance set at p<.05. RESULTS: ΔGlobalPSQI was not related to any measures, except ΔSD and ΔSQ (r=.39, r=.51; p<.05). ΔSD and ΔSQ were both significantly correlated to ΔIL-6 (r=-.21, r=-.23; p<.05). ΔIL-6 was positively correlated to ΔCRP (r=.32, p<.05), ΔTNFα (r=.43, p<.05), and ΔFCORT (r=.26, p<.05). ΔCRP was also significantly related to ΔTCORT (r=.24, p<.05). EEEAVG was not associated with any measures (p>.05). CONCLUSIONS: There appears to be a relationship, albeit weak, between sleep measures and IL-6, with increased SD and SQ (i.e. decreased PSQI score) related to increases in IL-6. Additionally, increased IL-6 was associated with increases in other proinflammatory and stress markers, potentially indicative of fuel mobilization and physiological repair responses. The cumulative load of the competitive season could indicate an increased need for recovery, thus yielding compensatory increases in SD and perceived SQ. Further research is warranted using objective sleep measures to examine the observed relationship in soccer players. Funding provided by Quest Diagnostics

592-P: Epidermal Nrf2 Orchestrates Tissue Regeneration through Direction Regulation of Ccl2

Diabetic ulcers are costly chronic wounds and are the leading cause of lower-extremity amputations. Dysfunctional redox balance underlies a key part of diabetic wound repair pathology that results from misregulation of master antioxidant gene regulator Nrf2. While Nrf2 regulation is relevant for wound repair, how Nrf2 onsets a regenerative response is unclear. Using in-depth analyses, we uncover Nrf2 expression in keratinocytes to be vital for physiologic wound repair. In vivo spatio-temporal analysis shows deregulated nuclear translocation of Nrf2 in diabetic wound keratinocytes (WT: 96.97%±3.6%; Db: 22.50%±16.4%; p&amp;lt;.005), which correlates with reduced activation of many antioxidant gene targets (p&amp;lt;.005). To elucidate the role of Nrf2 in the epidermis, we utilized double transgenic mice to conditionally delete Nrf2 in keratinocytes (K14 CreER; Nrf2fl/fl; cKO) in vivo. Importantly, we find loss of epidermal Nrf2 results in a significant wound repair delay that reminisces delays observed in diabetic mice (WT: 16.0±0d; Db: 32±0d; cKO: 33±2d; p&amp;lt;.0005). RNA-seq of cKO wound keratinocytes reveals Nrf2 regulates epidermal release of extrinsic cues that affect non-autologous responses that are critical for regeneration, most notably immune cell guidance (p&amp;lt;.05). The magnitude of this signaling defect is shown through failure of cKO wounds to traffic monocyte/macrophages to the injury site (WT: 130.0±15.0cells/area; cKO 35.0±2.6cells/area; p&amp;lt;.05). This defect results from reduced expression of Ccl2 in cKO wounds, which we find to possess a Nrf2-binding motif that exhibits dynamic Nrf2 binding upon wounding. Induced expression of Nrf2 in primary keratinocytes results in Ccl2 upregulation, and its application is sufficient for restoring physiologic wound regeneration in cKO and diabetic wounds (p&amp;lt;.0001). We provide evidence describing an essential role of Nrf2 in regulating critical wound healing events and provide the basis for continued investigation on its therapeutic value. Disclosure A.P. Villarreal Ponce: None. M. Tiruneh-Worku: None. J. Lee: None. J.A. David: None. C. Guerrero-Juarez: None. K. Dammeyer: None. J. Kuhn: None. J. Kwong: None. D. Ceradini: None. Funding American Diabetes Association/Pathway to Stop Diabetes (1-16-ACE-08 to D.C.)

The effects of polydeoxyribonucleotide on wound healing and tissue regeneration: a systematic review of the literature.

Aim: The present study evaluated the effects of polydeoxyribonucleotide (PDRN) on tissue regeneration, paying special attention to the molecular mechanisms that underlie its tissue remodeling actions to better identify its effective therapeutic potential in wound healing. Materials & methods: Strategic searches were conducted through MEDLINE/PubMed, Google Scholar, Scopus, Web of Science and the Cochrane Central Register of Controlled Trials, from their earliest available dates to March 2020. The studies were included with the following eligibility criteria: studies evaluating tissue regeneration, and being an in vitro, in vivo and clinical study. Results: Out of more than 90 articles, 34 fulfilled the eligibility criteria. All data obtained proved the ability of PDRN in promoting a physiological tissue repair through salvage pathway and adenosine A2A receptor activation. Conclusion: Up to date PDRN has proved promising results in term of wound regeneration, healing time and absence of side effects.

Root resorption and ensuing cementum repair by Wnt/β-catenin dependent mechanism

Physiological root resorption is a common occurrence in mammalian teeth, which suggests that there must be a corollary consisting of physiological cementum repair. The mechanism(s) responsible for this physiological repair process is unknown and was the focus of this study. Using a rat model, we explored first the prevalence of physiological root resorption and then asked whether this prevalence changed as a result of an osteoporotic phenotype. The cellular mechanisms of resorption were characterized using a combination of finite element modeling coupled with in-vivo histologic, molecular, and cellular analyses in rats. A potential molecular mechanism for cementum repair was uncovered using a strain of transgenic mice in which Wnt-responsive cells could be labeled and followed over time. In rats, most resorption lacunae were concentrated on the distal surfaces of the roots. Rat molars undergo a physiological tooth drift distally, and using finite element modeling, we calculated the magnitude of the compressive strains that accumulated on these surfaces in response to mastication. Although the overall strain magnitudes were low, they were constant and coincided with the presence of resorption lacunae. Where resorption lacunae were present, progeny from a Wnt-responsive population of stem cells, embedded in the periodontal ligament, directly contributed to the repair of the lacunae. Despite the fact that both are clastic conditions, an osteoporotic phenotype in rats was not associated with an increase in the prevalence of physiological root resorption. The location of the resorption lacunae corresponded to sites of low but constant compressive strains produced by physiological distal drift. At least 1 mechanism responsible for physiological cementum repair involved the contribution of Wnt-responsive stem or progenitor cells originating in the periodontal ligament. These data point toward a potential Wnt-based strategy to regenerate cementum in subjects with disease or damage.

Abstract A16: Understanding the principles of tissue repair that accelerate tumor initiation

Abstract Cancer development depends on the capacity of malignant cells to boost growth-promoting signals and restrain growth-inhibiting mechanisms, thus resulting in unbalanced homeostasis. Among growth-promoting mechanisms, sustained proliferation has been described as a fundamental trait of cancer cells. Hyperproliferative behavior is usually acquired in cancer by the constitutive activation of oncogenes such as H-Ras (G12V activating mutation). Previous work showed that H-Ras-G12V promotes epithelial cell hyperproliferation, a feature required but not sufficient to trigger cancer formation. Interestingly, injury has been linked to skin cancer emergence across several mutations. Yet it remains elusive how wound-triggered behaviors lead to cancer. Wound repair process increases cell proliferation, a key event to re-establish epithelial integrity. This observation suggests a possible cooperation between wound-induced and H-Ras-driven proliferation to reach the homeostatic breaking point that promotes cancer. To understand if enhanced proliferation during wound repair could contribute to cancer emergence, I tested the sufficiency of this behavior in promoting tumor in H-RasG12V-model in comparison to other hyperproliferative models, loss of function of the cell cycle inhibitor p21 (p21-/-) and loss of function of Tgf-beta Receptor I (Tgf-beta-RI-/-). Interestingly, in both Tgf-beta-RI-/- and p21-/- models, despite wound-increased cell proliferation, the tissue repairs normally without emergence of tumor. Surprisingly, in H-RasG12V-model wound repair does not increase significantly proliferation, yet tumors consistently develop in the wounded area after two weeks, in line with previous studies. These results indicate that wound-induced proliferation is insufficient to promote tumor initiation. To determine how differences in H-RasG12V cell numbers affect the wound repair outcome, I have activated H-RasG12V mutation in a mosaic fashion, conditions under which H-Ras cells outcompete wild-type neighboring cells via hyperproliferation during homeostatic conditions (Pineda and Greco, in revision). Unexpectedly, the repaired epithelium does not develop tumor after two weeks. Analyses of cellular behaviors show that wild-type cells display an hyperproliferative behaviors in response to the wound settings and they appear to outcompete the H-Ras cells, reversing the relationship established in homeostatic conditions. These data show that wound-induced proliferation seems to provide homeostatic protection against tumor formation. Wild-type cells force Hras-mutant cells to follow physiologic wound repair process suppressing their tumorigenic potential. In conclusion, my discoveries suggest that hyperproliferation is dispensable for tumor initiation. Furthermore, enhanced proliferation of the wild-type population through wounding may help eliminate oncogenic mutant cells that would otherwise integrate and expand into the tissue. Citation Format: Sara Gallini, Valentina Greco. Understanding the principles of tissue repair that accelerate tumor initiation [abstract]. In: Proceedings of the AACR Special Conference on Targeting RAS-Driven Cancers; 2018 Dec 9-12; San Diego, CA. Philadelphia (PA): AACR; Mol Cancer Res 2020;18(5_Suppl):Abstract nr A16.

The protective effect of beclomethasone dipropionate in the modeling of chronic obstructive pulmonary disease

The purpose of the study was to evaluate the protective effect of the inhaled glucocorticosteroids of beclomethasone dipropionate (BDP) using the experimental model of chronic obstructive pulmonary disease (COPD). Materials and Methods . The COPD model was reproduced in rats ( n = 30) during a discrete 60-day exposure to nitrogen dioxide, 9 individuals formed an intact group. Inhalation of BDP (50 micrograms per day) and control ( n = 15) placebo inhalation were performed for 60 days in the rats in the experimental group ( n = 15). The cell composition and cytokine enzymatic profile of bronchoalveolar lavage fluid (BALF), its content of secretory immunoglobulin A (sIgA) and surfactant protein D (SP-D) were determined by ELISA. Histological and morphometric lungs examination was performed. Results . Typical for COPD pathomorphological changes in the lungs were determined in the placebo group, the content of inflammatory cells and pro-inflammatory mediators in BALF increased, the functional activity of bronchoalveolar epithelium (SP-D, sIgA) deteriorated. There was a clear trend in the activity of neutrophilic-lymphocytic inflammation decrease with normalization of the profile of pro-inflammatory cytokines and enzymes in BALF In the group of animals receiving BDP; there was also a restoration of the morphological structure of the bronchoalveolar epithelium and improvement of its functional activity. Conclusion . The using of BDP in rats with the experimental COPD model had an expressed anti-inflammatory effect associated with the activation of physiological repair processes in the lungs, manifested by the restoration of structural, immune barrier integrity and functional activity of the bronchoalveolar epithelium.

Nitric Oxide in Dental Pulp Tissue: From Molecular Understanding to Clinical Application in Regenerative Endodontic Procedures.

Nitric oxide (NO), which is synthesized by the enzyme NO synthase (NOS), is a versatile endogenous molecule with multiple biological effects on many tissues and organs. In dental pulp tissue, NO has been found to play multifaceted roles in regulating physiological activities, inflammation processes, and tissue repair events, such as cell proliferation, neuronal degeneration, angiogenesis, and odontoblastic differentiation. However, there is a deficiency of detailed discussion on the NO-mediated interactions between inflammation and reparative/regenerative responses in wounded dental pulp tissue, which is a central determinant of ultimate clinical outcomes. Thus, the purpose of this review is to outline the current molecular understanding on the roles of Janus-faced molecule NO in dental pulp physiology, inflammation, and reparative activities. Based on this knowledge, advanced physicochemical techniques designed to manipulate the therapeutic potential of NOS and NO production in endodontic regeneration procedures are further discussed. Impact statement The interaction between inflammation and reparative/regenerative responses is very important for regenerative endodontic procedures, which are biologically based approaches intended to replace damaged tissues. Inside dental pulp tissue, endogenous nitric oxide (NO) is generated mainly by immunocompetent cells and dental pulp cells and mediates not only inflammatory/immune activities but also signaling cascades that regulate tissue repair and reconstruction, indicating its involvement in both tissue destruction and regeneration. Thus, it is feasible that NO acts as one of the indicators and modulators in dental pulp repair or regeneration under physiological and pathological conditions.

Advanced gelatin-based vascularization bioinks for extrusion-based bioprinting of vascularized bone equivalents

Bone tissue is highly vascularized. The crosstalk of vascular and osteogenic cells is not only responsible for the formation of the strongly divergent tissue types but also for their physiological maintenance and repair. Extrusion-based bioprinting presents a promising fabrication method for bone replacement. It allows for the production of large-volume constructs, which can be tailored to individual tissue defect geometries. In this study, we used the all-gelatin-based toolbox of methacryl-modified gelatin (GM), non-modified gelatin (G) and acetylated GM (GMA) to tailor both the properties of the bioink towards improved printability, and the properties of the crosslinked hydrogel towards enhanced support of vascular network formation by simple blending. The vasculogenic behavior of human dermal microvascular endothelial cells (HDMECs) and human adipose-derived stem cells (ASCs) was evaluated in the different hydrogel formulations for 14 days. Co-culture constructs including a vascular component and an osteogenic component (i.e. a bone bioink based on GM, hydroxyapatite and ASCs) were fabricated via extrusion-based bioprinting. Bioprinted co-culture constructs exhibited functional tissue-specific cells whose interplay positively affected the formation and maintenance of vascular-like structures. The setup further enabled the deposition of bone matrix associated proteins like collagen type I, fibronectin and alkaline phosphatase within the 30-day culture.

An alternative to skin graft for superficial surgical defect in oral cancer surgery

IntroductionAfter surgery for oral cavity cancer, superficial surgical defects are usually covered with a skin graft that can be harvested with different thicknesses depending on the reconstructive need. Despite its popularity and efficacy, this solution has the disadvantage of excessive harvesting times and scarring of the donor site. Other surgeons have proposed the use of bovine pericardium as a reconstructive solution. Its use in otorhinolaryngology especially after oral cavity surgery has never been reported. ObjectiveThe aim of this manuscript is to present our preliminary experience with the use of a collagen membrane obtained from bovine pericardium in the reconstruction of small and superficial defects after transoral resection of oral cavity tumors. MethodsA bovine collagen membrane was used to cover surgical defects in 19 consecutive patients undergoing transoral resection of small/superficial oral cancers. Photographs were obtained in the postoperative period to follow the healing process. We analyzed the pro and cons of this tool, recorded data on postoperative chewing-, speech- and taste-related quality of life, and tested the most appropriate settings providing the best reconstructive result. ResultsThe bovine collagen membrane allowed us to cover surgical defects of varying size in different oral sites. Shaping and placement proved to be simple. The membrane facilitated physiologic tissue repair: after one month it was completely absorbed and replaced by the patient’s own mucosa. No adverse features were observed in the cohort. ConclusionA bovine collagen membrane can represent a fast and easy solution in cases of split-thickness defect. Unlike a skin graft, it is not associated with donor site morbidity and allows the patient’s own mucosa to be restored with a more physiological result.

POSSIBILITIES OF IMMUNOLOGY STUDIES IN ESTIMATION OF VALIDITY OF BURN WOUNDS FOR SKIN PLASTICITY

Immunological features of burn disease largely reflect the state of general and local changes caused by the action of thermal factors. They are fundamental in formation of physiological repair of damaged tissue and disorders of the local immune system, lead to disruption of protective mechanisms with increased risk of occurrence and progression of local and systemic complications. It is the period of burn shock that is one of the main ones in the course and consequences of burn disease. In patients, the burn septicemia period even starting from the third day is characterized by severe immune changes, frequent generalization of inflammation and infection. Since one of the main tasks in treatment of patients with thermal trauma is the earliest possible recovery of lost skin, which consists in early surgical treatment (excision of necrotized tissues followed by simultaneous or delayed autodermoplasty), it is necessary to take into account metabolic disorders and changes in immune reactivity, affecting reparation of damaged tissues. To study the main immunological parameters in treatment of skin burn defects and their impact on the results of skin grafting, 17 patients with deep burns were examined. The main indices of metabolic status and immune reactivity in t surgical treatment of skin lesions, namely, innate immunity, humoral and cell components of immunity, metabolism (phagocytic activity of neutrophils, oxygen−dependent metabolism of neutrophils, concentration of peptides) differentiation clusters CD22 +, CD25 +, HLA−DR +) were examined. It is established that the corresponding changes in the indices can be the markers to predict the results of skin grafting. In this research it was found that with an unfavorable result of autodermoplasty in the patients with deep burns significant changes in immune reactivity and metabolic disorders were revealed. Altered immune reactivity due to increased circulating immune complexes and medium molecular weight peptides that provide opsonization and elimination of cytotoxic antigens in patients with deep burns may affect the results of skin grafting in surgical treatment of skin defects. Key words: burns, immune reactivity, dermatoplasty, metabolic state, autological skin transplantation.

The “adductome”: A limited repertoire of adducted proteins in human cells

Proteins form adducts with nucleic acids in a variety of contexts, and these adducts may be cytotoxic if not repaired. Here we apply a proteomic approach to identification of proteins adducted to DNA or RNA in normally proliferating cells. This approach combines RADAR fractionation of proteins covalently bound to nucleic acids with quantitative mass spectrometry (MS). We demonstrate that “RADAR-MS” can quantify induction of TOP1- or TOP2-DNA adducts in cells treated with topotecan or etoposide, respectively, and also identify intermediates in physiological adduct repair. We validate RADAR-MS for discovery of previously unknown adducts by determining the repertoires of adducted proteins in two different normally proliferating human cell lines, CCRF-CEM T cells and GM639 fibroblasts. These repertoires are significantly similar with one another and exhibit robust correlations in their quantitative profiles (Spearman r = 0.52). A very similar repertoire is identified by the classical approach of CsCl buoyant density gradient centrifugation. We find that in normally proliferating human cells, the repertoire of adducted proteins — the “adductome” — is comprised of a limited number of proteins belonging to specific functional groups, and that it is greatly enriched for histones, HMG proteins and proteins involved in RNA splicing. Treatment with low concentrations of formaldehyde caused little change in the composition of the repertoire of adducted proteins, suggesting that reactive aldehydes generated by ongoing metabolic processes may contribute to protein adduction in normally proliferating cells. The identification of an endogenous adductome highlights the importance of adduct repair in maintaining genomic structure and the potential for deficiencies in adduct repair to contribute to cancer.

Truncus Arteriosus with Anomalous Origin and Intramural Course of the Right Coronary Arterie: A Surgical Challenge

The truncus arteriosus communis is a very complex congenital cardiac malformation occurring in less than 1% of all congenital heart disease patients. Early repair remains one of the most challenging procedures in congenital cardiac surgery. Due to improvement in surgical reconstruction strategies over the past years, there is an acceptable short and long-term survival for those patients. However, each new case represents a “high mountain to climb” in ambition to achieve physiological repair with acceptable hemodynamic and a good long-term survival. We therefore present a very special case with anomalous origin and intramural course of the right coronary artery.

Circulating angiogenic cells in glioblastoma: toward defining crucial functional differences in CAC-induced neoplastic versus reactive neovascularization.

BackgroundIn order to identify suitable therapeutic targets for glioma anti-angiogenic therapy, the process of neovascularization mediated by circulating angiogenic cells (CACs) needs to be scrutinized.MethodsIn the present study, we compared the expression of neovascularization-related genes by 3 circulating CAC subsets (hematopoietic progenitor cells [HPCs], CD34+, and KDR+ cells; internal controls: peripheral blood mononuclear cells and circulating endothelial cells) of treatment-naïve patients with glioblastoma (GBM) to those of patients undergoing reactive neovascularization (myocardial infarction (MI). CACs from umbilical cord (representing developmental neovascularization) and healthy subjects served as controls. Fluorescent-activated cell sorting was used to isolate CACs, RT-PCR to determine the expression levels of a panel of 48 neovascularization-related genes, and Luminex assays to measure plasma levels of 21 CAC-related circulating molecules.ResultsWe found essential differences in gene expression between GBM and MI CACs. GBM CACs had a higher expression of proangiogenic factors (especially, KITL, CXCL12, and JAG1), growth factor and chemotactic receptors (IGF1R, TGFBR2, CXCR4, and CCR2), adhesion receptor monomers (ITGA5 and ITGA6), and matricellular factor POSTN. In addition, we found major differences in the levels of neovascularization-related plasma factors. A strong positive correlation between plasma MMP9 levels and expression of CXCR4 in the CAC subset of HPCs was found in GBM patients.ConclusionsOur findings indicate that CAC-mediated neovascularization in GBM is characterized by more efficient CAC homing to target tissue and a more potent proangiogenic response than in physiologic tissue repair in MI. Our findings can aid in selecting targets for therapeutic strategies acting against GBM-specific CACs.