Formation Of Necrotic Tissue Research Articles

Reconstruction after inappropriate lower limb open degloving injury management resulting in the necrotic wound: a case report

Background: Trauma with shear mechanisms, which are typically the result of after trauma regarding traffic incidents, is the primary cause of degloving injuries. The condition is typified by the avulsion of skin and subcutaneous tissue, resulting in a deficiency in coverage and, in extreme situations, the loss of the limb involved. Case Presentation: A 58-year-old male was struck by a car and sustained a direct blow to his right lower leg from a rubber tire. The patient was hospitalized and did primary wound closure. A week later, the patient sought a second opinion in a different hospital due to necrotic tissue formation in his lower limb due to previous primary closure disregarding tissue vitality through split-thickness skin excision (STSE). Conclusion: This case reported management of necrotic tissue and reconstruction defect closure by skin graft through surgical cleaning and debridement. After establishing a viable grafting bed, split-thickness skin grafts were applied as covering.

Assessment of active constituents and total flavonoids of Ammi majus plant extracts on immunological and kidney protective activities in mice

The Ammi majus (Kella) plant is frequently used to cure various health issues. This study aimed to investigate the most important phytochemical compounds of Kella seeds and evaluate the effect of its aqueous and alcoholic extracts on CCl4-induced nephrotoxicity in mice using a count of white blood cells (WBC) test and some biochemical markers for renal functions besides the histopathological study of kidney tissue. According to secondary metabolite analysis, the seeds contained tannins, alkaloids, saponins, flavonoids, and polyphenols at varying levels depending on the solvent utilized. Regarding total flavonoids, the alcoholic extract showed the highest concentration (193.2±25.7 mg/g) compared to the aqueous extract (176.3±19.2 mg/g). The WBC count test in the in vivo study showed an improved immune system by increasing the number of WBCs in mice treated with plant extracts and reducing the toxic effects of the CCl4 compound compared with a negative control group. In the positive control group (treated mice with CCl4), the biochemical analysis and histological study of the kidney sections revealed that CCl4 causes nephrotoxicity through increasing urea and creatinine concentrations in the blood and lowering total protein content, as well as the formation of necrotic tissue in the kidney sections. In contrast, these markers decreased in groups of mice treated with plant extracts, particularly alcoholic extract. In conclusion, the A. majus plant can improve kidney function during CCl4 doses. Consequently, it could be a promising treatment for nephrotoxicity caused by certain drugs. Keywords: Ammi majus; kidney markers; nephrotoxicity

Investigation of reversible histone acetylation and dynamics in gene expression regulation using 3D liver spheroid model

BackgroundThree-dimensional (3D) cell culture has emerged as an alternative approach to 2D flat culture to model more accurately the phenotype of solid tissue in laboratories. Culturing cells in 3D more precisely recapitulates physiological conditions of tissues, as these cells reduce activities related to proliferation, focusing their energy consumption toward metabolism and homeostasis.ResultsHere, we demonstrate that 3D liver spheroids are a suitable system to model chromatin dynamics and response to epigenetics inhibitors. To delay necrotic tissue formation despite proliferation arrest, we utilize rotating bioreactors that apply active media diffusion and low shearing forces. We demonstrate that the proteome and the metabolome of our model resemble typical liver functions. We prove that spheroids respond to sodium butyrate (NaBut) treatment, an inhibitor of histone deacetylases (HDACi), by upregulating histone acetylation and transcriptional activation. As expected, NaBut treatment impaired specific cellular functions, including the energy metabolism. More importantly, we demonstrate that spheroids reestablish their original proteome and transcriptome, including pre-treatment levels of histone acetylation, metabolism, and protein expression once the standard culture condition is restored after treatment. Given the slow replication rate (> 40 days) of cells in 3D spheroids, our model enables to monitor the recovery of approximately the same cells that underwent treatment, demonstrating that NaBut does not have long-lasting effects on histone acetylation and gene expression. These results suggest that our model system can be used to quantify molecular memory on chromatin.ConclusionTogether, we established an innovative cell culture system that can be used to model anomalously decondensing chromatin in physiological cell growth and rule out epigenetics inheritance if cells recover the original phenotype after treatment. The transient epigenetics effects demonstrated here highlight the relevance of using a 3D culture model system that could be very useful in studies requiring long-term drug treatment conditions that would not be possible using a 2D cell monolayer system.

Clinical and Histological Effects of N-acetyl Cysteine Intraperitoneal Injection on Primary Wound Healing in Rabbits.

Aims: This study aims to investigate the effect of ten days of intraperitoneal injection of N-acetyl cysteine (NAC) on full thickness wound healing of the skin, using a rabbit model. Materials and Methods: Thirty - male rabbits were used to conduct this study. A full – thickness linear incision, (10 mm) was induced on the back of each rabbit and divided into two groups. Group 1: no treatment (control group) and group 2 (NAC-treated group) was injected intraperitoneally ten days before wound induction. Animals were randomly divided into three groups according to sacrificing date (1, 3 and 7) days. The site of intervention was assessed clinically and histopathologically on the 1st, 3rd, and 7th day of the experimental procedure. Results: The clinical observation of tissue type revealed that there were significant differences in type of tissue at 1 and 3 days at p-value ≤ 0.05, and the wound healing was converted to granulation tissue without slough and necrotic tissue formation. There was no significant difference at 7 days compared to the control group. The histopathological finding showed that there were significant differences in angiogenesis and granulation tissue formation between the two groups at 1 and 3 days at p-value ≤ 0.05, while there was no significant difference at 7 days. There was a significant difference of reepithelization at 3 and 7 days at p-value ≤ 0.05., Conclusions: Ten days of intraperitoneally N-acetyl cysteine injection before surgical procedures will significantly enhance the process of primary wound healing of rabbit skin.on secondary wounds.

Characterization and quantification of necrotic tissues and morphology in multicellular ovarian cancer tumor spheroids using optical coherence tomography.

The three-dimensional (3D) tumor spheroid model is a critical tool for high-throughput ovarian cancer research and anticancer drug development in vitro. However, the 3D structure prevents high-resolution imaging of the inner side of the spheroids. We aim to visualize and characterize 3D morphological and physiological information of the contact multicellular ovarian tumor spheroids growing over time. We intend to further evaluate the distinctive evolutions of the tumor spheroid and necrotic tissue volumes in different cell numbers and determine the most appropriate mathematical model for fitting the growth of tumor spheroids and necrotic tissues. A label-free and noninvasive swept-source optical coherence tomography (SS-OCT) imaging platform was applied to obtain two-dimensional (2D) and 3D morphologies of ovarian tumor spheroids over 18 days. Ovarian tumor spheroids of two different initial cell numbers (5,000- and 50,000- cells) were cultured and imaged (each day) over the time of growth in 18 days. Four mathematical models (Exponential-Linear, Gompertz, logistic, and Boltzmann) were employed to describe the growth kinetics of the tumor spheroids volume and necrotic tissues. Ovarian tumor spheroids have different growth curves with different initial cell numbers and their growths contain different stages with various growth rates over 18 days. The volumes of 50,000-cells spheroids and the corresponding necrotic tissues are larger than that of the 5,000-cells spheroids. The formation of necrotic tissue in 5,000-cells numbers is slower than that in the 50,000-cells ones. Moreover, the Boltzmann model exhibits the best fitting performance for the growth of tumor spheroids and necrotic tissues. Optical coherence tomography (OCT) can serve as a promising imaging modality to visualize and characterize morphological and physiological features of multicellular ovarian tumor spheroids. The Boltzmann model integrating with 3D OCT data of ovarian tumor spheroids provides great potential for high-throughput cancer research in vitro and aiding in drug development.

Pictorial essay of vestibular incision outcomes from transoral endoscopic thyroidectomy.

The transoral endoscopic thyroidectomy vestibular approach (TOETVA) has emerged as a new treatment option for patients with selected thyroid disease requiring surgery. The aim of this pictorial essay is to illustrate the healing outcomes of the vestibular incisions. TOETVA patients were recruited at two Centers in China and Italy. TOETVA is initiated with one 10-20-mm median incision in the center of the oral vestibule 10 mm above the inferior labial frenulum, and two 5-mm lateral incisions, just below the lower lip near the labial commissure. Healing of the vestibular incision was monitored through serial photographs 1, 3, 7, 30, and 90 days after surgery. Outcomes were evaluated by Landry's score, time to healing, issues affecting wound outcomes, scar, fibrin, granulation, necrotic tissue formation, and infections. Results of TOETVA were monitored in 52 patients. There were no postoperative infections. All lateral incisions demonstrated favorable surgical outcomes. Landry's criteria scores indicated worse outcomes for the median incisions vs. the lateral ones (p<0.05). Median incisions healed well in 65.4% of patients, but 34.6% of patients had visible scars from the median incision 90 days after surgery. Eight (15.4%) had cicatricial diathesis, seven (13.5%) experienced displacement of the stitches, and three (5.8%) developed synechia with gingiva. When the central vestibular incision was <10mm from the gingiva, patients tended to form synechia (60%). There were no significant differences in wound healing between the Chinese and Italian patients. Knowledge of vestibular incision healing is essential to provide practical TOETVA clinical guide and to define optimal outcomes evaluation for transoral surgeons. Vestibular wound problems were confined only to the central incision.

Garlic burn injuries- a systematic review of reported cases.

Medicinal plants have many beneficial effects on human health. Garlic (Allium sativum, Alliaceae) is one of the most famous herbal species, used for various diseases and conditions. Unfortunately, garlic is also associated with adverse effects, including cutaneous manifestations. In this review, burn injuries caused by application of raw garlic are reported. Searching through PubMed, Google Scholar and ResearchGate, a total of 32 articles with 39 patients were found. Demographics of patients, reasons for garlic use, details on garlic application, as well as description of burns and its treatment are thoroughly described and discussed. In most of the cases, garlic caused second-degree burns, although some circumstances can cause formation of necrotic tissue. Various body parts were affected, legs being most common. The chemistry of garlic is also presented, with focus on volatile organic sulfur compounds, which also seem to be responsible for burns formation. Treatment of garlic burns was mainly symptomatic, and various types of drugs were used. Although not commonly expected, garlic should be taken into consideration as causative agents of burns by treating doctors, and patients should be advised against application of fresh garlic onto skin and mucosa.

Comparative evaluation of pulpal repair after direct pulp capping using stem cell therapy and biodentine: An animal study.

The response of the dentin-pulp complex in rat teeth was investigated after direct capping with biodentine with or without bone marrow-derived stem cells (BMDSCs). Following mechanical exposure, pulps were randomly capped with one of the followings materials: calcium hydroxide, biodentine or 1×105 BMDSCs mL-1 + biodentine. Histological examination was performed by light microscopy after 1, 3 and 5weeks. Inflammatory reaction, necrotic tissue formation and calcific bridge formation were scored. Analysis showed that compared with the effects of calcium hydroxide or biodentine, BMDSCs+biodentine substantially reduced inflammatory reaction and necrotic tissue while promoting calcified tissue formation. Therefore, the combination of biodentine and BMDSCs could potentially stimulate pulp tissue regeneration after direct pulp capping.

Mango cut incision for pressure ulcer necrotic tissue clearance: An easier and safer method to facilitate chemical debridement in severely-comorbid patients

Abstract Background Treatment of pressure ulcer with necrotic tissue formation is challenging in old patients with severe comorbidities. Although indicated and recommended, surgical debridement cannot always be applied because of general conditions. Simple, convenient, and minimally invasive intervention is required to facilitate chemical debridement of necrotic tissue. Methods Seventeen patients suffering from intractable pressure ulcer complicated with necrotic tissue formation underwent conventional debridement (CD) or mango cut incision (MCI). Feasibility of MCI method was evaluated by comparing clinical outcomes between patients who underwent CD and MCI. Results Between patients undergoing CD and MCI, there was no significant difference in time for necrotic tissue clearance (3.1 ± 2.0 vs. 4.0 ± 1.5 weeks, P = 0.366), nor in time for pressure ulcer cure (14.7 ± 6.2 vs. 12.7 ± 5.6 weeks, P = 0.566). Time required for intervention was significantly longer in CD than that in MCI (173.8 ± 44.5 vs. 29.4 ± 13.3 s, P Conclusions MCI allows minimally invasive clearance of necrotic tissue with clinically acceptable outcomes compatible to CD, and can be a choice of method for necrosis-complicated pressure ulcers in patients with severe comorbidities.

Plasmin Is Essential in Preventing Periodontitis in Mice

Periodontitis involves bacterial infection, inflammation of the periodontium, degradation of gum tissue, and alveolar bone resorption, which eventually leads to loss of teeth. To study the role of the broad-spectrum protease plasmin in periodontitis, we examined the oral health of plasminogen (Plg)-deficient mice. In wild-type mice, the periodontium was unaffected at all time points studied; in Plg-deficient mice, periodontitis progressed rapidly, within 20 weeks. Morphological study results of Plg-deficient mice revealed detachment of gingival tissue, resorption of the cementum layer, formation of necrotic tissue, and severe alveolar bone degradation. IHC staining showed massive infiltration of neutrophils in the periodontal tissues. Interestingly, doubly deficient mice, lacking both tissue- and urokinase-type plasminogen activators, developed periodontal disease similar to that in Plg-deficient mice; however, mice lacking only tissue- or urokinase-type plasminogen activator remained healthy. Supplementation by injection of Plg-deficient mice with human plasminogen for 10 days led to necrotic tissue absorption, inflammation subsidence, and full regeneration of gum tissues. Notably, there was also partial regrowth of degraded alveolar bone. Taken together, our results show that plasminogen is essential for the maintenance of a healthy periodontium and plays an important role in combating the spontaneous development of chronic periodontitis. Moreover, reversal to healthy status after supplementation of Plg-deficient mice with plasminogen suggests the possibility of using plasminogen for therapy of periodontal diseases.

A comparative study of myostatin, follistatin and decorin expression in muscle of different origin

Muscle regeneration supports muscle function in aging, and plays a role in the functional impairment caused by progressive neuromuscular diseases. Major substances controlling this process are growth factors and the extracellular matrix (ECM). Thus, follistatin is known to antagonize the function of several members of the TGF-β family of secreted signaling factors, including myostatin-the most powerful inhibitor of muscle growth characterized to date. Decorin-a small leucine-rich proteoglycan-traps myostatin and modulates its activity towards myogenic cells in the ECM. In addition, there are few reports concerning the regenerative muscle process of masseter muscles, which are of branchial arch origin, in mdx mice. Thus, in order to clarify the muscle regenerative process of masseter muscle, gene and protein expression of myostatin, follistatin and decorin were examined using the tibialis anterior (TA)muscle as a positive control. In both muscles, a gradual increase in mRNA myostatin, follistatin and decorin expression was detected, with the increase being greater in TA muscle than in masseter muscle. At 2weeks, both muscles exhibited normal skeletal muscle cells. At 3weeks, masseter muscle demonstrated scant areas of necrosis, whereas large necrotic zones were seen in TA muscle. At 4weeks, the formation of necrotic tissue and presence of follistatin protein was observed clearly in masseter muscle. This result indicates that follistatin production is stimulated in the presence of necrosis. Interestingly, both muscles showed the same process of muscular formation, but with different time frames, which could be related to muscle origin.

Advanced Mechanical Properties of Porous Hydroxyapatite Ceramics Prepared Using Hydroxyapatite Slip and its Slurry Synthesis

There is a clinical need for synthetic scaffolds that will promote bone regeneration. Important factors include obtaining an optimal porosity and size of interconnecting macropores whilst maintaining scaffold mechanical strength, enabling complete penetration of cells and nutrients throughout the scaffold, preventing the formation of necrotic tissue in the centre of the scaffold. To address this we investigated flexural strength of bimodal porous apatite ceramics prepared using apatite slurry and its slurry synthesis was studied. Slips with different contents of HAp (K-HAp and T-HAp) and deflocculant were prepared by milling in a pot mill. The viscosity of slurries made of commercial T-HAp powder showed a drop after 3 hours’ milling, but the viscosity of slurry with high solid content of k-HAp and 2.0 wt% deflocculant increased with an increase of milling time after 2 hours’ milling. The porosity and flexural strength of the porous HAp prepared by heating the foam dipped in K-HAp slip with 2.0 wt% of deflocculant and 0.5wt% of foaming regent heated at 1200°C were 62.4 % and 14.7 MPa, and those in T-HAp were 59.7 % and 15.2 MPa with 1.5 wt% of deflocculant and 0.5wt% of foaming regent heated at 1200°C.

Thermal imaging of cucumber leaves affected by downy mildew and environmental conditions

Pathogenesis of Pseudoperonospora cubensis causing downy mildew of cucumber resulted in changes in the metabolic processes within cucumber leaves including the transpiration rate. Due to the negative correlation between transpiration rate and leaf temperature, digital infrared thermography permitted a non-invasive monitoring and an indirect visualization of downy mildew development. Depending on the stage of pathogenesis and the topology of chloroses and necroses, infection resulted in a typical temperature pattern. Spatial heterogeneity of the leaf temperature could be quantified by the maximum temperature difference (MTD) within a leaf. The MTD increased during pathogenesis with the formation of necrotic tissue and was related to disease severity as described by linear and quadratic regression curves. Under controlled conditions, changes in temperature of infected leaves allowed the discrimination between healthy and infected areas in thermograms, even before visible symptoms of downy mildew appeared. Environmental conditions during thermographic measurement, in particular air temperature and humidity, as well as water content and age of the leaf influenced the temperature of its surface. Conditions enhancing the transpiration rate facilitated the detection of changes in leaf temperature of infected leaves at early stages of infection. As modified by environmental conditions, MTD alone is not suitable for the quantification of downy mildew severity in the field.

Sclerotinia sclerotiorum: When “to be or not to be” a pathogen?

Sclerotinia sclerotiorum is unusual among necrotrophic pathogens in its requirement for senescent tissues to establish an infection and to complete the life cycle. A model for the infection process has emerged whereby the pathogenic phase is bounded by saprophytic phases; the distinction being that the dead tissues in the latter are generated by the actions of the pathogen. Initial colonization of dead tissue provides nutrients for pathogen establishment and resources to infect healthy plant tissue. The early pathogenicity stage involves production of oxalic acid and the expression of cell wall degrading enzymes, such as specific isoforms of polygalacturonase (SSPG1) and protease (ASPS), at the expanding edge of the lesion. Such activities release small molecules (oligo-galacturonides and peptides) that serve to induce the expression of a second wave of degradative enzymes that collectively bring about the total dissolution of the plant tissue. Oxalic acid and other metabolites and enzymes suppress host defences during the pathogenic phase, while other components initiate host cell death responses leading to the formation of necrotic tissue. The pathogenic phase is followed by a second saprophytic phase, the transition to which is effected by declining cAMP levels as glucose becomes available and further hydrolytic enzyme synthesis is repressed. Low cAMP levels and an acidic environment generated by the secretion of oxalic acid promote sclerotial development and completion of the life cycle. This review brings together histological, biochemical and molecular information gathered over the past several decades to develop this tri-phasic model for infection. In several instances, studies with Botrytis species are drawn upon for supplemental and supportive evidence for this model. In this process, we attempt to outline how the interplay between glucose levels, cAMP and ambient pH serves to coordinate the transition between these phases and dictate the biochemical and developmental events that define them.

The influence of dispersant concentration on the pore morphology of hydroxyapatite ceramics for bone tissue engineering

There is a clinical need for synthetic scaffolds that will promote bone regeneration. Important factors include obtaining an optimal porosity and size of interconnecting windows whilst maintaining scaffold mechanical strength, enabling complete penetration of cells and nutrients throughout the scaffold, preventing the formation of necrotic tissue in the centre of the scaffold. To address this we investigated varying slip deflocculation in order to control the resulting porosity, pore size and interconnecting window size whilst maintaining mechanical strength. Hydroxyapatite (HA) porous ceramics were prepared using a modified slip casting process. Rheological measurements of the HA slips were used to identify deflocculation conditions which resulted in changes in the cell and window sizes of the resulting ceramics. Sintered ceramics were characterised by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Pore and window size distribution was determined by SEM. XRD analysis confirmed that the crystal structure remained HA after the sintering process. SEM showed that HA porous ceramics presented a highly interconnected porous network with average pore sizes ranging from 391±39 to 495±25 μm. The average window size varied from 73±5 to 135±7 μm. Pore diameters obtained were controllable in the range 200–500 μm. Window sizes were in the range 30–250 μm. The use of dispersant concentration allows pore and window size to be modified whilst maintaining control over porosity demonstrated by a porosity of 85% for seven different dispersant concentrations. The advantage of this approach allows the correlation between the rheological conditions of the slip and the resultant sintered ceramic properties. In particular, optimising the ceramic strength by controlling the agglomeration during the casting process.

Induction of plant responses to oviposition and feeding by herbivorous arthropods: a comparison

AbstractPlants may respond both to feeding and oviposition by herbivorous insects. While responses of plants to feeding damage by herbivores have been studied intensively during the past decades, only a few, but growing number of studies consider the reactions of plants towards egg deposition by herbivorous insects. Plants showing defensive response to oviposition by herbivores do not ‘wait’ until being damaged by feeding, but may instead react towards one of the initial steps of herbivore attack, the egg deposition. Direct plant defensive responses to feeding act directly against the feeding stages of the herbivores. However, a plant may also show direct defensive responses to egg deposition by (a) formation of neoplasms, (b) formation of necrotic tissue (= hypersensitive response), and (c) production of oviposition deterrents. All these plant reactions have directly negative effects on the eggs, hatching larvae, or on the ovipositing females. Indirect plant defensive responses to feeding result in the emission of volatiles (= synomones) that attract predators or parasitoids of the feeding stages. A few recent studies have shown that plants are able to emit volatiles also in response to egg deposition and that these volatiles attract egg parasitoids. Studies on the mechanisms of induction of synomones by egg deposition show several parallels to the mechanisms of induction of plant responses by feeding damage. When considering induced plant defence against herbivores from an evolutionary point of view, the question arises whether herbivores evolved the ability to circumvent or even to exploit the plant's defensive responses. The reactions of herbivores to oviposition induced plant responses are compared with their reactions to feeding induced plant responses.

Invasion of rust ( Puccinia poarum) pycnia and aecia on coltsfoot ( Tussilago farfara) by secondary pathogens: death of host leaves

Necrotrophic fungi were cultured after isolation from rust (Puccinia poarum) pustules on leaves of Tussilago farfara, collected in the field. Healthy and rusted (P. poarum) leaves of T. farfara were re-inoculated in a greenhouse with these potential secondary invaders and development of necrosis and death of leaves was determined. Alternaria alternata, Fusarium sp., Phoma exigua and Phoma glomerata caused formation of necrotic tissue and (non-systemic) death of leaves, whereas leaves inoculated with Cladosporium herbarum and Epicoccum nigrum were similar to leaves inoculated with sterile water. Greater necrosis developed when aecia rather than pycnia were inoculated and at both stages secondary damage increased with increasing pustule density. Comparison with other host-rust systems and aspects of biological weed control are discussed.

An Electron Spin Resonance Investigation of Internal Rust Spot, A Physiological Disorder of the Potato Tuber

ESR spectroscopy has been used to investigate the formation of paramagnetic species during the development of internal rust spot (IRS) in the potato tuber. Production of free radicals and oxidation of metal ions such as Fe(II) and Mn(II) occur when necrotic tissue is formed. However, since IRS develops in periods of calcium stress (low calcium supply), it is suggested that the principal cause of the disorder is a loss of cell membrane integrity which is brought about by a lack of calcium. Cell senescence and the formation of necrotic tissue may then result either from increased oxygen radical production within the cell or from oxidation of metal complexes in the extracellular regions of the tissue.