Tissue Disintegration Research Articles

Investigation of PRDM10 and PRDM13 Expression in Developing Mouse Embryos by an Optimized PACT-Based Embryo Clearing Method.

Recent developments in tissue clearing methods have significantly advanced the three-dimensional analysis of biological structures in whole, intact tissue, providing a greater understanding of spatial relationships and biological circuits. Nonetheless, studies have reported issues with maintaining structural integrity and preventing tissue disintegration, limiting the wide application of these techniques to fragile tissues such as developing embryos. Here, we present an optimized passive tissue clearing technique (PACT)-based embryo clearing method, initial embedding PACT (IMPACT)-Basic, that improves tissue rigidity without compromising optical transparency. We also present IMPACT-Advance, which is specifically optimized for thin slices of mouse embryos past E13.5. We demonstrate proof-of-concept by investigating the expression of two relatively understudied PR domain (PRDM) proteins, PRDM10 and PRDM13, in intact cleared mouse embryos at various stages of development. We observed strong PRDM10 and PRDM13 expression in the developing nervous system and skeletal cartilage, suggesting a functional role for these proteins in these tissues throughout embryogenesis.

Variations of Structural and Functional Traits of Azolla pinnata R. Br. in Response to Crude Oil Pollution in Arid Regions

In oil-producing countries, water pollution by crude petroleum oil frequently occurs and causes many environmental problems. This study aims to investigate the effect of crude petroleum oil on the growth and functional trails of the economically important freshwater plant Azolla pinnata R. Br. and to report on the plant’s resistance to this abiotic stress. Plants were raised in an open greenhouse experiment under different levels of crude oil pollution ranging from 0.5 to 2.0 g/L. Plant functional traits were monitored over a three-week period. Plant cover of A. pinnata was decreased with the increased levels of oil pollution. The total chlorophyll content decreased from 0.76 mg/g fresh weight under 2 g/L oil treatment after 21 days of growth. The chlorophyll a/b ratio exceeded the unity at crude oil treatments above 1 g/L, with values reaching 2.78 after seven days, while after 21 days, the ratio ranged from 1.14 to 1.31. The carotenoid content ranged from 0.17 mg/g in the control to 0.11 mg/g in the 2 g/L oil treatment. The carotenoid content varied over time in relation to DNA% damage, which increased from 3.63% in the control to 11.36% in the highest oil treatment level of 2 g/L. The crude oil stress caused severe damage in the frond tissues and chloroplast structure of A. pinnata, including a less compacted palisade, the malformation of the epidermis, the disintegration of parenchyma tissue, and the lysis and malformation of the chloroplasts. Since A. pinnata cannot withstand high concentrations of crude oil pollution, it is for use in the remediation of slightly polluted freshwaters up to 0.5 g/L.

Ulcerative lesions a primary aspect

Lesions of the skin or of a mucous membrane which is accompanied by formation of pus and necrosis of surrounding tissue, usually resulting from inflammation or ischemia. A break in skin or mucous membrane with loss of surface tissue, disintegration and necrosis of epithelial tissue and often pus. Ulceration occurs as a result of dermal or subcutaneous tissue loss, and it usually develops on the base of a tumoral or inflammatory nodule. Thus, an important part of the diseases in this chapter were also mentioned in other chapters of the book. Ulcerative lesions may sometimes develop due to trauma.

Tissue-autonomous immune response regulates stress signaling during hypertrophy.

Postmitotic tissues are incapable of replacing damaged cells through proliferation, but need to rely on buffering mechanisms to prevent tissue disintegration. By constitutively activating the Ras/MAPK-pathway via RasV12-overexpression in the postmitotic salivary glands (SGs) of Drosophila larvae, we overrode the glands adaptability to growth signals and induced hypertrophy. The accompanied loss of tissue integrity, recognition by cellular immunity, and cell death are all buffered by blocking stress signaling through a genuine tissue-autonomous immune response. This novel, spatio-temporally tightly regulated mechanism relies on the inhibition of a feedback-loop in the JNK-pathway by the immune effector and antimicrobial peptide Drosomycin. While this interaction might allow growing SGs to cope with temporary stress, continuous Drosomycin expression in RasV12-glands favors unrestricted hypertrophy. These findings indicate the necessity to refine therapeutic approaches that stimulate immune responses by acknowledging their possible, detrimental effects in damaged or stressed tissues.

The effect of a systemic inflammatory response on adaptive mechanisms and the state of homeostasis in patients with respiratory tuberculosis in combination with chronic obstructive pulmonary disease

The influence of the systemic inflammatory response on the adaptive mechanisms and the state of homeostasis of the body in patients with respiratory tuberculosis against the background of chronic obstructive pulmonary disease is considered. It has been established that respiratory tuberculosis and chronic obstructive pulmonary disease are widespread among the population and are important causes of bronchopulmonary morbidity and mortality. Chronic obstructive pulmonary disease is determined in one third of newly diagnosed patients with respiratory tuberculosis. The combined course of respiratory tuberculosis and chronic obstructive pulmonary disease is a mutually aggravating condition. Comorbid pathology is much more difficult, accompanied by severe intoxication, disintegration of lung tissue and bacterial excretion. Biomarkers and the severity of the systemic inflammatory response are of great clinical and diagnostic value in chronic obstructive pulmonary disease. It was determined that the systemic inflammatory response in chronic obstructive pulmonary disease is characterized by endothelial dysfunction of the vascular wall, significant changes in white blood cells, changes in the protein spectrum of the blood, and lipid metabolism disorders. The manifestations of systemic inflammation and endothelial dysfunction, characteristic of chronic obstructive pulmonary disease, in patients with respiratory tuberculosis, aggravate the course of both diseases. The comorbid state is also characterized by a change in the lipid profile of patients, an increase in the content of total cholesterol and atherogenic fractions. These changes are interrelated with the state of adaptive mechanisms, homeostasis and reactivity of the organism. The state of homeostasis largely determines the development, course and outcome of pathological processes characteristic of tuberculous inflammation and inflammation in chronic obstructive pulmonary disease, and the increase in the effectiveness of the treatment is closely related to the restoration of homeostatic balance and reactivity of the body. The availability of methods for determining the homeostatic balance of the body in clinical practice, with their high information content, allows a personalized approach to the management of patients with comorbidity.

Screening and histopathological characterization of sunflower germplasm for resistance to Macrophomina phaseolina

ABSTRACT Twenty-two sunflower germplasms were screened for resistance to Macrophomina phaseolina to select parental genetic resources useful for the development of charcoal rot–resistant sunflower cultivars. Potting soil inoculated with pathogen (10 mL pot−1, 2 × 105 sclerotia mL−1) sown with sunflower seeds was examined for disease severity index (%), disease incidence (%), mortality (%), and growth inhibition index (%) 90 d after inoculation. None of the germplasm was disease-free; four were found to be resistant, five moderately resistant, six moderately susceptible, five susceptible, and two highly susceptible. All inoculated plants exhibited disease symptoms both externally and internally. Mild to severe symptoms included brown lesions on aboveground plant, pith disintegration in stem, and shredded appearance of tap root. Histopathological features exposed different colonization mechanism of the pathogen in the resistant and susceptible cultivars. Physical blockage, tissue disintegration, blackening and rupturing of cortical, pith and vascular regions by fungal mycelia, and sclerotia and pycnidia causing large spaces in the center of stem rendered it a hollow structure in all susceptible germplasm. However, stem and root tissues of the resistant germplasm indicated local infection restricted to few cells. This suggested expression of true resistance genes in resistant germplasm. Therefore, the sunflower lines resistant to the M. phaseolina infection are potential genetic resources for the development of quality sunflower cultivars resistant to charcoal rot disease.

Enzymatic tissue disintegration leads to the loss of immunophenotype of breast cancer stem cells.

e13089 Background: Cancer stem cells (CSC) are a population in the complex hierarchy of tumor tissue responsible for growth, metastasis and resistance to chemotherapy and radiotherapy. The purpose of the study was to reveal the effect of the enzymatic disintegration of breast cancer (BC) tissue on the CSC immunophenotype. Methods: BC tumor samples obtained during surgery were placed for 2 hours in a sterile Hanks’ solution immediately after collection. Samples were fragmented to 1 mm in diameter, the fragments were evenly distributed into 4 Petri dishes with (6 cm diameter) and placed in DMEM medium (Gibco, USA) without collagenase and with the addition of collagenase (Biolot, Russia) to a final concentration of 150, 300 and 450 units/ml. Samples were cultured for 48 hours at 37°C and 5.5% CO2. On day 2, the samples incubated in collagenase were grinded by passing through tips of decreasing diameter; the reference sample was grinded in the Medimachine system (BD, USA). The effect of enzymatic tissue disintegration on the preservation of BC SC immunophenotype (CD24low/-CD44+) was evaluated using the BD FacsCanto II flow cytometer (BD, USA) and PE Mouse Anti-Human CD24 (clone ML5; BD, USA) and FITC Mouse Anti-Human CD44 (clone G44-26; BD, USA) antibodies. Results: The total number of isolated cells increased almost exponentially with increasing collagenase concentration. The trypan blue test showed that cell viability did not change significantly with an increase in collagenase concentration and was approximately 50%, being an order of magnitude higher compared to mechanical dissociation (4%). However, 48 h incubation in a collagenase solution led decreased the number of CD44+ cells in proportion to the enzyme concentration by 3 to 10 times in comparison with the control. Similarly, inhibition of CD24 expression was observed compared with the control, inevitably leading to a decreased purity of the isolated subpopulation with the CD24low/-CD44+ phenotype. Conclusions: Despite an increase in the yield of viable cells, prolonged incubation in a collagenase solution leads to a loss of the immunophenotype of BC SC.

Cell disintegration of apple peels induced by pulsed electric field and efficiency of bio-compound extraction

The pulsed electric field (PEF) assisted extraction of bio-compounds (soluble solids concentration, °Brix, and total polyphenol content, TPC) from apple peels was studied. The aqueous suspensions of apple peels were treated by PEF with different intensities, E (480–1200V/cm), and different treatment times, tPEF (0–2s). The cell disintegration was analyzed using measurement of electrical conductivity (disintegration index, Zc) and microstructure evaluation by confocal laser scanning microscopy (microscopic cell disintegration index, Zd). The near linear Zc (Zd) dependencies were obtained for PEF treatment protocols with different treatment time, tPEF, and electric field intensity, E. The °Brix and TPC extraction efficiencies were dependent upon applied value of E. For example, at the highest PEF intensity, E=1200V/cm, and Zc≈1, the enhancements in values of °Brix and TPC were approximately the same ≈3.15. However, at lower PEF intensities (480, 600 and 800V/cm) and the fixed value of Zc the extraction of soluble matter was more effective compared to TPC. Therefore, the extraction efficiency of different bio-molecules is not only affected by the level of tissue disintegration (by value of Zc). The other details of PEF protocols (e.g., value of E) may be also important.

Новый метод неинвазивного механического разрушения опухолей простаты с помощью импульсного фокусированного ультразвука

of the study: demonstrate the feasibility of non-invasive mechanical disintegration of human prostate tissue using pulsed high-intensity focused ultrasound (pHIFU), a method termed boiling histotripsy. An ultrasound experimental system was developed for producing localized mechanical lesions in ex vivo biological tissue samples under ultrasound guidance. A series of experiments was carried out to create small single-focus lesions (volume < 2 mm3) and one large lesion (volume > 50 mm3) in ex vivo prostate tissue samples. After irradiation, two samples were bisected to visualize the region of destruction; the other tissue samples were examined histologically. During pHIFU irradiation under B-mode ultrasound guidance, a region of increased echogenicity caused by formation of vapor-gas bubbles was visualized in the target region. After exposure, small and large lesions filled with a suspension of liquefied tissue were observed. Histological examination confirmed that the prostate tissue in the focal region was disintegrated into subcellular fragments. A pilot study showed the feasibility of using boiling histotripsy as a non-invasive method for treating prostate diseases.

Investigation of PRDM7 and PRDM12 expression pattern during mouse embryonic development by using a modified passive clearing technique

Recent developments in tissue clearing methods such as CLARITY (Clear Lipid-exchanged Acrylamide-hybridized Rigid Imaging/Immunostaining/In situ hybridization-compatible Tissue hYdrogel) have allowed for the three-dimensional analysis of biological structures in whole, intact tissue, providing greater understanding of spatial relationships and biological circuits. Nonetheless, studies have reported issues with maintaining structural integrity and preventing tissue disintegration, preventing the wide application of these techniques to fragile tissues such as developing embryos. Here, we present optimized passive clearing techniques, mPACT-A, that improve tissue rigidity without the expense of optical transparency. We also present a further modified mPACT-A protocol that is specifically optimized for handling mouse embryos, which are small and fragile, such that they easily dismantle when processed via established tissue clearing methods. We demonstrate proof-of-concept by investigating the expression of two relatively understudied PRDM proteins, PRDM7 and PRDM12, in intact cleared mouse embryos at various stages of development. We observed strong PRDM7 and PRDM12 expression in the developing mouse nervous system, suggestive of potential roles in neural development that will be tested in future functional studies.

Management of azoospermia with special emphasis on microdissection testicular sperm extraction (mTESE) in non obstructive azoospermia prior to IVF/ICSI to optimize sperm retrieval rates, pregnancy, live birth rates–a systematic review

Previously there was no option for infertility due to non obstructive azoospermia (NOA). But with advent of technology NOA has become treatable with the use of testicular sperm extraction and IVF. The most correct approach for sperm retrieval remains microdissection testicular sperm extraction (mTESE). This systematic review discusses and examines the literature in terms of Patient optimization before mTESE, Technique of mTESE, along with post mTESE testicular tissue processing. Preoperative patient medical therapy, data for varicocele repair support increased sperm retrieval, pregnancy and return of sperm in the ejaculate. Post mTESE tissue processing has few studies where comparison has been done, though most studies support the combination of mechanical mincing and use of type 4 collagenase for tissue disintegration along with pentoxifylline in assisting in identification of motile and viable spermatozoa for intractoplamic injection.

Pilot in vivo studies on transcutaneous boiling histotripsy in porcine liver and kidney

Boiling histotripsy (BH) is a High Intensity Focused Ultrasound (HIFU) method for precise mechanical disintegration of target tissue using millisecond-long pulses containing shocks. BH treatments with real-time ultrasound (US) guidance allowed by BH-generated bubbles were previously demonstrated ex vivo and in vivo in exposed porcine liver and small animals. Here, the feasibility of US-guided transabdominal and partially transcostal BH ablation of kidney and liver in an acute in vivo swine model was evaluated for 6 animals. BH parameters were: 1.5 MHz frequency, 5–30 pulses of 1–10 ms duration per focus, 1% duty cycle, peak acoustic powers 0.9–3.8 kW, sonication foci spaced 1–1.5 mm apart in a rectangular grid with 5–15 mm linear dimensions. In kidneys, well-demarcated volumetric BH lesions were generated without respiratory gating and renal medulla and collecting system were more resistant to BH than cortex. The treatment was accelerated 10-fold by using shorter BH pulses of larger peak power without affecting the quality of tissue fractionation. In liver, respiratory motion and aberrations from subcutaneous fat affected the treatment but increasing the peak power provided successful lesion generation. These data indicate BH is a promising technology for transabdominal and transcostal mechanical ablation of tumors in kidney and liver.

The extremely low energy cost of biosynthesis in holometabolous insect larvae

The metabolic cost of growth, which quantifies the amount of energy required to synthesize a unit of biomass, is an important component of an animal’s ontogenetic energy budget. Here we investigated this quantity as well as other energy budget variables of the larvae of a holometabolous insect species, Vanessa cardui (painted lady). We found that the high growth rate of this caterpillar cannot be explained by its metabolic rate and the percentage of the metabolic energy allocated to growth; the key to understanding its fast growth is the extremely low cost of growth, 336 Joules/gram of dry mass.The metabolic cost of growth in caterpillars is 15–65 times lower than that of the endothermic and ectothermic species investigated in previous studies. Our results suggest that the low cost cannot be attributed to its body composition, diet composition, or body size. To explain the “cheap price” of growth in caterpillars, we assumed that a high metabolic cost for biosynthesis resulted in a high “quality” of cells, which have fewer errors during biosynthesis and higher resistance to stressors. Considering the life history of the caterpillars, i.e., tissue disintegration during metamorphosis and a short developmental period and lifespan, we hypothesized that an energy budget that allocates a large amount of energy to biosynthesizing high quality cells would be selected against in this species. As a preliminary test of this hypothesis, we estimated the metabolic cost of growth in larvae of Manduca sexta (tobacco hornworm) and nymphs of Blatta lateralis (Turkestan cockroach). The preliminary data supported our hypothesis.

Effects of palytoxins extracted from Ostreopsis ovata on the oxidative stress and immune responses in Pacific white shrimp Litopenaeus vannamei

Palytoxins (PLTXs) are a group of complex and poisonous marine natural products that are toxic to marine life and even human beings. In the present study, the oxidative stress and immune response in the hepatopancreas and gills of Litopenaeus vannamei were assessed for 72 h after injection with PLTX extracts. Chemical and physiological parameters, e.g., the respiratory burst (O2−), activities of antioxidant enzymes, oxidative damage to lipids, carbonylation of proteins, and immune gene mRNA expression levels, were analysed. The results showed that the PLTX extract was not fatal to the shrimp but could reduce their mobility. The O2− levels in the gills gradually increased after exposure to PLTX extracts and were significantly higher than those in the control from 6 to 72 h. The malondialdehyde content, lipid peroxidation, protein carbonyl levels, and total antioxidant capacity in the gills all peaked at 12 h. At the same time, the gills were loosely connected, there was a clear disintegration of the epithelial tissue, and the stratum corneum disappeared after 12 h. In addition, compared to those in the control group, the PLTX extract treatment increased the O2− content, malondialdehyde content, lipid peroxidation, and protein carbonyl levels from 12 to 72 h, 24–48 h, 12–24 h, and 12–72 h after injection in the hepatopancreas of the shrimp, respectively. Both the Crustin and Toll gene expression levels significantly increased in the hepatopancreas compared to those in the control 6–72 h after injection of the toxin. In parallel, the expression levels of the manganese superoxide dismutase gene gradually decreased from 6 to 48 h and returned to normal levels after 72 h. Interestingly, the total antioxidant capacity also significantly increased compared to that in the control from 6 to 72 h. Our results indicate that although PLTX extracts cause lipid peroxidation and carbonylation of proteins in hepatopancreatic cells, leading to their damage, they did not cause a decrease in the total antioxidant capacity of the hepatopancreas.

Vitamin E but Not GSH Decreases Reactive Oxygen Species Accumulation and Enhances Sperm Production during In Vitro Maturation of Frozen-Thawed Prepubertal Mouse Testicular Tissue.

Freezing–thawing procedures and in vitro culture conditions are considered as a source of stress associated with increased reactive oxygen species (ROS) generation, leading to a damaged cell aerobic metabolism and consequently to oxidative stress. In the present study, we sought to investigate whether vitamin E (Vit E) or reduced glutathione (GSH) enhances sperm production by decreasing ROS accumulation during in vitro maturation of prepubertal mice testes. Testes of prepubertal mice were cryopreserved using a freezing medium supplemented or not supplemented with Vit E and were cultured after thawing. In presence of Rol alone in culture medium, frozen-thawed (F-T) testicular tissues exhibited a higher ROS accumulation than fresh tissue during in vitro culture. However, Vit E supplementation in freezing, thawing, and culture media significantly decreased cytoplasmic ROS accumulation in F-T testicular tissue during in vitro maturation when compared with F-T testicular tissue cultured in the presence of Rol alone, whereas GSH supplementation in culture medium significantly increased ROS accumulation associated with cytolysis and tissue disintegration. Vit E but not GSH promoted a better in vitro sperm production and was a suitable ROS scavenger and effective molecule to improve the yield of in vitro spermatogenesis from F-T prepubertal mice testes. The prevention of oxidative stress in the cytoplasmic compartment should be regarded as a potential strategy for improving testicular tissue viability and functionality during the freeze–thaw procedure and in vitro maturation.

Physiological Adaptations to Extreme Maternal and Allomaternal Care in Spiders

Some semelparous species show terminal investment by suicidal offspring provisioning. This requires internal cellular disintegration for the production of regurgitated food and in preparation for the sacrifice of the female body to the offspring, however, we have limited insights into the extent and costs of such physiological modifications. Extreme provisioning is hypothesized to be limited to reproducing individuals because it requires physiological alterations triggered by reproduction. However, non-reproducing helpers-at-the-nest have been shown to engage in suicidal provisioning, prompting us to ask whether helpers undergo similar physiological alterations to brood provisioning as mothers, which would represent an adaptation to cooperative breeding. Using an experimental approach, we investigated the physiological consequences of extended maternal care in the solitary spider Stegodyphus lineatus and the cooperative breeder S. dumicola, and whether non-reproducing helpers (virgin allomothers) in S. dumicola show physiological adaptations to brood provisioning. To identify costs of offspring provisioning, we determined the energy expenditure (standard metabolic rate; SMR) and tissue disintegration over the course of brood care. In both species, brood care is associated with elevated SMR, which was highest in allomothers. Brood care results in progressive disintegration of midgut tissue, which also occurred in allomothers. On experimental offspring removal, these responses are reversible but only until the onset of regurgitation feeding, marking a physiological “point-of-no-return.” The mechanism underlying the onset of physiological responses is unknown, but based on our finding of mature eggs in mothers and allomothers, as opposed to the undeveloped eggs in virgins of the solitary species, we propose that oocyte maturation is a central adaptation in non-reproducing helpers to provide terminal allomaternal care.

Trichoderma harzianum- and Methyl Jasmonate-Induced Resistance to Bipolaris sorokiniana Through Enhanced Phenylpropanoid Activities in Bread Wheat (Triticum aestivum L.).

The aim of the present study was to evaluate the impact of Trichoderma harzianum UBSTH-501- and methyl jasmonate-induced systemic resistance and their integration on the spot blotch pathogen, Bipolaris sorokiniana through enhanced phenylpropanoid activities in bread wheat (Triticum aestivum L.). It was found that the application of MeJA (>100 mg L–1) inhibits the germination of B. sorokiniana spores under controlled laboratory conditions. To assess the effect of MeJA (150 mg L–1) in combination with the biocontrol agent T. harzianum UBSTH-501 in vivo, a green house experiment was conducted. For this, biocontrol agent T. harzianum UBSTH-501 was applied as seed treatment, whereas MeJA (150 mg L–1) was applied 5 days prior to pathogen inoculation. Results indicated that application of MeJA (150 mg L–1) did not affect the root colonization of wheat by T. harzianum UBSTH-501 in the rhizosphere. The combined application of T. harzianum UBSTH-501 and MeJA also enhanced indole acetic acid production in the rhizosphere (4.92 μg g–1 of soil) which in turn helps in plant growth and development. Further, the combined application found to enhance the activities of defense related enzymes viz. catalase (5.92 EU min–1 g–1 fresh wt.), ascorbate peroxidase [μmol ascorbate oxidized (mg prot)–1 min–1], phenylalanine ammonia lyase (102.25 μmol cinnamic acid h–1 mg–1 fresh wt.) and peroxidase (6.95 Unit mg–1 min–1 fresh wt.) significantly in the plants under treatment which was further confirmed by assessing the transcript level of PAL and peroxidase genes using semi-quantitative PCR approach. The results showed manifold increase in salicylic acid (SA) along with enhanced accumulation of total free phenolics, ferulic acid, caffeic acid, coumaric acid, and chlorogenic acid in the leaves of the plants treated with the biocontrol agent alone or in combination with MeJA. A significant decrease in the disease severity (17.46%) and area under disease progress curve (630.32) were also observed in the treatments with biocontrol agent and MeJA in combination as compared to B. sorokiniana alone treated plant (56.95% and 945.50, respectively). Up-regulation of phenylpropanoid cascades in response to exogenous application of MeJA and the biocontrol agent was observed. It was depicted from the results that PAL is the primary route for lignin production in wheat which reduces cell wall disruption and tissue disintegration and increases suberization and lignification of the plant cell as seen by Scanning Electron microphotographs. These results clearly indicated that exogenous application of MeJA with T. harzianum inducing JA- and/or SA-dependent defense signaling after pathogen challenge may increase the resistance to spot blotch by stimulating enzymatic activities and the accumulation of phenolic compounds in a cooperative manner. This study apparently provides the evidence of biochemical cross-talk and physiological responses in wheat following MeJA and biocontrol agent treatment during the bio-trophic infection.

Influence of Pulsed Electric Field and Ohmic Heating Pretreatments on Enzyme and Antioxidant Activity of Fruit and Vegetable Juices.

The objective of this work was to optimize pulsed electric field (PEF) or ohmic heating (OH) application for carrot and apple mashes treatment at different preheating temperatures (40, 60 or 80 °C). The effect of tissue disintegration on the properties of recovered juices was quantified, taking into account the colour change, the antioxidant activity and the enzyme activity of peroxidase (POD) in both carrot and apple juice and polyphenol oxidase (PPO) in apple juice. Lower ΔE and an increase of the antioxidant activity were obtained for juice samples treated with temperature at 80 °C with or without PEF and OH pretreatment compared with those of untreated samples. The inactivation by 90% for POD and PPO was achieved when a temperature of 80 °C was applied for both carrot and apple mash. A better retention of plant secondary metabolites from carrot and apple mashes could be achieved by additional PEF or OH application. Obtained results are the basis for the development of targeted processing concepts considering the release, inactivation and retention of ingredients.

Histomorphometric analysis of pulp submitted to the action of bromelain associated with irrigation solutions

Aim: The objective of this study was to evaluate the tissue disgregation capacity of pulp in different solutions associated or not with bromelain. Methodology: Fifty bovine mandibular incisors were used, divided into five groups: C: Control, H: sodium hypochlorite 2.5%, B: bromelain, BL: bromelain + L-cysteine, BH: bromelain + sodium hypochlorite 2.5%. The pulp fragments were stored at -20 °C, washed with saline solution and moved to 25°C in eppendorf tubes with 1 ml of each substance. For the histomorphometric evaluation, the pulp fragments were prepared as histological routine, observed with optical microscopy and evaluated using ImageJ 1.49 software. Results: The histomorphometric results showed that, in C: there was no alteration per tissue; H: there was a peripheral and central tissue disintegration; B: there was a protein and cellular degradation pattern, from the peripheral to the central area; BL: there was a central degradation. In BH, showed an effect enhanced by bromelain, when related to sodium hypochlorite, showing greater tissue degradation. Conclusions: The association of bromelain with sodium hypochlorite potentiated the disintegration action of the pulp, opening possibilities for several clinical applications.

Fat body disintegration after freezing stress is a consequence rather than a cause of freezing injury in larvae of Drosophila melanogaster

Extracellular freezing of insect body water may cause lethal injury either by direct mechanical stress exerted by growing ice crystals on cells and tissues or, indirectly, by deleterious physico-chemical effects linked to freeze-induced cell dehydration. Here we present results showing that the macroscopic damage (cell ruptures, tissue disintegration) to fat body of Drosophila melanogaster is not directly caused by mechanical forces linked to growth of ice crystals but rather represents a secondary consequence of other primary freeze injuries occurring at subcellular or microscopic levels. Larvae of D. melanogaster were acclimated to produce variants ranging from freeze susceptible to freeze tolerant. Then, larvae were exposed to supercooling and freezing stresses at different subzero temperatures. The larval survival and macroscopic damage to fat body tissue was scored in 1632 larvae exposed to cold stress. In most cases, fat body damage was not evident immediately following cold stress but developed later. This suggests that the fat body disintegration is a consequence rather than a cause of cold injury. Analysis of fat body membrane phospholipids revealed that increased freeze tolerance was associated with increased relative proportion of phosphatidylethanolamines (PEs) at the expense of phosphatidylcholines (PCs). The PE/PC ratio increased from 1.08 in freeze-susceptible larvae to 2.10 in freeze-tolerant larvae. The potential effects of changing PE/PC ratio on phospholipid bilayer stability upon supercooling and freezing stress are discussed.