Tissue Collapse Research Articles

Metformin Attenuates Cyclosporine A-induced Renal Fibrosis in Rats.

The aim of the present study was to investigate the therapeutic potential of metformin in preventing cyclosporine A (CsA)-induced nephrotoxicity. Three groups of adult male Sprague-Dawley rats were treated with vehicle, CsA, and CsA + metformin for 4 weeks following 1 week on low sodium diet, respectively. At the end of treatment, all animals were euthanized, and the samples of kidney, urine, and blood were collected for functional, morphological, and molecular biological evaluation. Metformin effectively prevented CsA-induced renal dysfunction with increased creatinine clearance rate and reduced blood urea nitrogen and serum creatinine, as well as less proteinuria in comparison to the CsA group. Morphologically, metformin ameliorated CsA-induced renal fibrosis and tissue collapse in the areas of arteries, glomeruli, and proximal tubules. We further demonstrated that the antifibrotic effects of metformin in kidneys treated with CsA were associated with decreased phosphorylation of extracellular signal-regulated kinase1/2 (ERK1/2). In conclusion, our study revealed new therapeutic potential of metformin to attenuate calcineurin inhibitor-induced renal fibrosis, which was closely related to the suppression of MEK/ERK1/2 pathway.

RETRACTED: The role of laryngeal ultrasound in diagnosis of infant laryngomalacia

The purpose of this study was to evaluate the role of laryngeal ultrasound in diagnosis of infant laryngomalacia. Forty consecutive infant patients with inspiratory stridor or other laryngeal symptoms underwent flexible fiberoptic nasopharyngolaryngoscopy and laryngeal ultrasound examination from January 2014 to May 2014. The curling angle of the epiglottis and/or arytenoid tissue collapses on laryngeal ultrasound during inspiration were used to diagnose infant laryngomalacia. The value of laryngeal ultrasound in diagnosis of infant laryngomalacia was evaluated and further compared to that of flexible fiberoptic nasopharyngolaryngoscopy. The mean angle of the curling epiglottis in 26 patients with laryngomalacia was 69.1 ± 8.1 degrees, while the mean angle of the slightly curling epiglottis in 12 patients without laryngomalacia was 89.6 ± 9.7 degrees (p < 0.0001). Arytenoid tissue collapses were found in 24 patients with laryngomalacia and only one patient without laryngomalacia had a local collapse of arytenoid tissue (p < 0.0001). Twenty six of the 28 patients with laryngomalacia diagnosed by flexible fiberoptic nasopharyngolaryngoscopy were detected by laryngeal ultrasound. There was an excellent consistency between laryngeal ultrasound and flexible fiberoptic nasopharyngolaryngoscopy in the detection of infant laryngomalacia (κ = 0.826). Laryngeal ultrasound had a sensitivity of 96.3%, a specificity of 84.6%, a positive predictive value of 92.9%, and a negative predictive value of 91.7% in diagnosing infant laryngomalacia. Laryngeal ultrasound can help diagnose infant laryngomalacia through visualizing omega-shaped epiglottis and/or arytenoid tissue collapse during inspiration. The modality has an excellent consistency with flexible fiberoptic nasopharyngolaryngoscopy in diagnosis of the disease.

Condutividade elétrica como indicador de danos por temperaturas baixas em folhas de feijão

The electrical conductivity test indirectly evaluates cell membrane disorganization by quantifying the electrolytes released into the water after tissue imbibing. The objective of this work was to evaluate methodological variations in the electrical conductivity test, for it to serve as an indicator of low temperature-induced damages and estimate the cold tolerance of bean plants. Cultivar IPR Uirapuru plants were subjected to minimum temperatures of 4 °C, 2 °C, 0 °C, -1 °C, -2 °C, -3 °C, and -4 °C for 1 h in a growth chamber under controlled conditions. After the treatment period, the response of plants to cold stress was evaluated by determination of the total protein content, and catalase (CAT) and ascorbate peroxidase (APX) enzymatic activities, and evaluation of photosystem II (Fm/Fv) efficiency and leaf anatomy. These results were compared with those obtained in the electrical conductivity test, which was performed in plants under cold stress as well as under a non-stress environment, with 2, 4, 6, and 8 leaf discs immersed in 30 mL of distilled water for 24 h in BOD, at temperatures of 25 °C, 30 °C, and 35°C. Analysis of variance was performed using a completely randomized design, and for electrical conductivity, a number of discs × cold stress temperature combinations were used for each soak temperature. The averages were compared using the Turkey's test at 5% and 10% probability. Pearson correlation coefficient (r) between the conductivity averages and other cold stress evaluation data was also performed. The results showed a marked reduction in the ratio (Fv/Fm) only in the treatments at -3 °C and -4°C, which indicated tissue death. At temperatures below 0°C, there was a collapse of the leaf blade tissues, and it was not possible to differentiate the palisade parenchyma from the spongy parenchyma in the treatments at -2°C, -3°C, and -4°C. There was an increase in the protein content since the temperature -3°C. The enzyme activity of CAT decrease at -4°C whereas that of APX increased. In the electrical conductivity test, there was a significant interaction between soak temperature and the number of discs, and an increase in conductivity of the solution with a decrease in temperature was verified in several treatments, among which, the combination that best correlated with the other tests was 25°C with six leaf discs. It was concluded that the electrical conductivity test presents results similar to those obtained from other physiological, biochemical, and anatomical tests, and therefore, it can be used to evaluate the damage caused by low temperatures in bean plants.

Functions and mechanisms: polygalacturonases from plant pathogenic fungi as pathogenicity and virulence factors

Polygalacturonases (PGs) are widely distributed pectic enzymes in microorganisms that are plant pathogens, and those that are not plant pathogens, and in plants themselves. PGs degrade the adhesive pectic substances of the middle lamella and cell wall, contributing to fungal penetration, plant tissue collapse and nutrient acquisition. Not all PGs that are produced by plant pathogens are required for pathogenicity or virulence, and PGs are present in nonpathogens. This review provides an overview of the functions and mechanisms of PGs in the pathogenicity and virulence of fungi and interpretations of the keys to PG involvement in pathogenesis.

How Sliding and Hydrodynamics Contribute to Articular Cartilage Fluid and Lubrication Recovery

The tribological functions of cartilage are governed primarily by its interstitial fluid content, but the means by which cartilage recovers and retains interstitial fluid during articulation following periods of static loading remain unclear. Recently, we demonstrated a phenomenon in which articular cartilage recovers fluid at the loaded contact interface; we refer to this as ‘tribological rehydration’. Our findings were consistent with two competing hypotheses: (1) that hydrodynamic pressures exceeded local interstitial pressures; (2) that fluid from the trailing wedge squeezed into the porous surface during direction reversals (reciprocal wedging). In this paper, we use unidirectional sliding to eliminate the potential effects of reciprocal wedging on tribological rehydration. We observed the same tribological rehydration effects from speed as in our previous reciprocating studies; thus, any effects of reciprocation are secondary to those of sliding itself. Tribological rehydration was enhanced by increased speeds, decreased loads, increased lubricant viscosity, and increased sample diameter. Although our results are generally consistent with a hydrodynamic interpretation of tribological rehydration, our attempts to eliminate the convergence zone by systematically decreasing the sample diameter failed to extinguish tribological rehydration. This final observation reveals an extremely robust mechanism for preventing tissue collapse and highlights some of the remaining challenges in modeling cartilage as a mechanical and tribological material.

Alterations of root architecture and cell wall modifications in Tilia cordata Miller (Linden) growing on mining sludge

Trees are considered good candidates for phytoremediation of soils contaminated with trace elements (TE), e.g. mine tailings. Using two year-old Tilia cordata plants, we demonstrated the nature and the scale of root architecture, especially root apices, as an indicator of mining sludge toxicity and plant capability to cope with these stress conditions. The novelty of our research is the analysis of the root response to substrate with extremely high concentrations of numerous toxic TE, and the 3D illustration of the disorders in root apex architecture using a clarity technique for confocal microscopy.The analysis demonstrates (1) a marked reduction in the size of the root apex zones (2) the occurrence of vascular tissues abnormally close to the root apex (3) collapse of the internal tissues in many root apices. Simultaneously, at the cellular level we observed some signs of a defensive response - such as a common increase of cell wall (CW) thickness and the formation of local CW thickenings - that enlarge the CW capacity for TE sequestration. However, we also detected harmful effects. Among others, a massive deposition of TE in the middle lamella which caused major damage - probably one of the reasons why the inner tissues of the root apex often collapsed – and the formation of incomplete CWs resulting in the occurrence of extremely large cells. Moreover, many cells of the root apex exhibited degenerated protoplasts.All these alterations indicate the harsh conditions for lime growth and survival and simultaneously, the manifestation of a defensive response.The obtained results allowed us to conclude that analysis of the nature and scale of structural alterations in roots can be useful indicators of plant ability to cope with stress conditions, e.g. in prospect of using the examined plants for reclamation of soils contaminated with TE.

The role of KDEL-tailed cysteine endopeptidases of Arabidopsis (AtCEP2 and AtCEP1) in root development.

Plants encode a unique group of papain-type cysteine endopeptidases (CysEP) characterized by a C-terminal KDEL endoplasmic reticulum retention signal (KDEL-CysEP) and an unusually broad substrate specificity. The three Arabidopsis KDEL-CysEPs (AtCEP1, AtCEP2, and AtCEP3) are differentially expressed in vegetative and generative tissues undergoing programmed cell death (PCD). While KDEL-CysEPs have been shown to be implicated in the collapse of tissues during PCD, roles of these peptidases in processes other than PCD are unknown. Using mCherry-AtCEP2 and EGFP-AtCEP1 reporter proteins in wild type versus atcep2 or atcep1 mutant plants, we explored the participation of AtCEP in young root development. Loss of AtCEP2, but not AtCEP1 resulted in shorter primary roots due to a decrease in cell length in the lateral root (LR) cap, and impairs extension of primary root epidermis cells such as trichoblasts in the elongation zone. AtCEP2 was localized to root cap corpses adherent to epidermal cells in the rapid elongation zone. AtCEP1 and AtCEP2 are expressed in root epidermis cells that are separated for LR emergence. Loss of AtCEP1 or AtCEP2 caused delayed emergence of LR primordia. KDEL-CysEPs might be involved in developmental tissue remodeling by supporting cell wall elongation and cell separation.

Early Experience with Local Custom Made Synthetic Bone Construct for the Treatment of Bone Defect

Introduction: Segmental bone defect can be treated with autologous bone graft and bone transport. Synthetic bone graft has successfully been used for the treatment of metaphyseal fracture or bone cyst. However, their use for the treatment of segmental bone defect has not been establish. Recently, a local company has produced a biodegradable custom made synthetic bone construct phosphate-based materials that is used to treat fractures and bone defect. Materials and Methods: After getting approval from Medical Device Agency, we used SBC to treat segmental bone defect in our patients. A case series review was conducted in these cases. Results: Three patients underwent surgery using SBC as a spacer to fill the defect at the docking site to prevent soft tissue collapse in one patient and as a replacement for bone autologous bone grafting in two patients. In our observation granules resorbtion ranged from 40-80% by 6 months with no radiological evidence of new bone formation. SBC mixed with bone marrow aspirate failed to harden into a palette. Although no new bone formation was seen at the docking site, insertion of SBC prevents soft tissue invagination and reduced the need of a second surgery to remove other conventional spacers. Conclusion: SBC may be used as a spacer to prevent soft tissue interposition and skin invagination in bone transport. However mixing it with bone marrow aspirate resulted in failure to form beads and does not form bone.

Inhibitory Effect of Standardized Curcuma xanthorrhiza Supercritical Extract on LPS-Induced Periodontitis in Rats.

Periodontitis, which is a severe inflammatory disease caused by endotoxins secreted from oral pathogens, destructs gingival tissue and alveolar bone. Curcuma xanthorrhiza, commonly called Java turmeric, has been shown to possess anti-bacterial and anti-inflammatory activities. The present study evaluated the inhibitory effect of C. xanthorrhiza supercritical extract (CXS) standardized with xanthorrhizol on lipopolysaccharide (LPS)-induced periodontitis in an animal model. LPS was topically injected into the periodontium of Sprague-Dawley rats to induce periodontitis and CXS (30 and 100 mg·kg-1·day-1) was orally administered after day 12. Histologically, CXS inhibited the collapse of gingival tissue by preventing cell infiltration. CXS significantly downregulated the expression of matrix metalloproteases (MMPs) and inflammation-related biomarkers, such as nuclear factor-kappa B (NF-κB) and interleukin-1 beta (IL-1β) in gingival tissue. CXS also improved bone remodeling by downregulating osteoclastic transcription factors, such as nuclear factor of activated T-cells c1 (NFATc1), tartrate-resistant acid phosphatase (TRAP), and cathepsin K. In addition, CXS upregulated osteoblast differentiation-related markers, alkaline phosphate (ALP) and collagen type I alpha (COLA1). Thus, CXS can ameliorate periodontitis by inhibiting inflammation and improving bone remodeling.

Intra-annual dynamics of phloem formation and ultrastructural changes in sieve tubes in Fagus sylvatica.

Despite increased interest in the timing and dynamics of phloem formation, seasonal changes in the structure of phloem sieve elements remain largely unexplored. To understand better the dynamics of phloem formation and the functioning of sieve tubes in the youngest phloem in Fagus sylvatica L., we investigated repeatedly taken phloem samples during the growing season of 2017 by means of light microscopy, and transmission and scanning electron microscopy. Phloem formation started with the expansion of the overwintered early phloem sieve tubes adjacent to the cambium and concurrent cambial cell production. The highest phloem growth rate was observed in general 1 week after the onset of cambial cell production, whereas the transition from early to late phloem occurred at the end of May. Cambial cell production ceased at the end of July. The final width of the phloem increment was 184 ± 10 μm, with an early phloem proportion of 59%. Collapse of older phloem tissue is a progressive process, which continuously occurred during the sampling period. Collapse of early phloem sieve tubes started shortly after the cessation of cambial cell production. Prior to the onset of radial growth, late phloem from the previous year represented 80% of the total non-collapsed part; during the growth period, this percentage decreased to 20%. Differences were observed in both sieve tube ultrastructure and sieve plate geometry between the youngest and older phloem. However, sieve plates were never completely occluded by callose, suggesting that processes affecting the functionality of sieve tubes may differ in the case of regular collapse or injury. The youngest parts of the phloem increment from the previous year (i.e., previous late phloem) continue functioning for some time in the current growing season, but the two-step development of overwintered phloem cells also ensures a sufficient translocation pathway for photosynthates to the actively growing tissues.

Depigmentation efficacy of galacturonic acid through tyrosinase regulation in B16 murine melanoma cells and a three-dimensional human skin equivalent.

Sugar is a well-known cosmetic ingredient for moisturizing skin with minimal side-effects. Several reports have demonstrated an antimelanogenic effect of sugar in melanocytes. We evaluated the whitening efficacy of galacturonic acid (GA), the main component of pectin, as an anti-melanogenic agent. GA significantly suppressed melanin synthesis and secretion in a concentration-dependent manner in α-melanocyte stimulating hormone-treated B16 melanoma cells, and inhibited tyrosinase activity and expression at a dose of 10 mmol/L. In a three-dimensional human skin equivalent (MelanoDerm), GA clearly brightened tissue colour. Haematoxylin and eosin and Fontana-Masson (F&M) staining of tissue sections revealed decreased melanin production without skin tissue collapse in the presence of GA. Interestingly, GA dramatically suppressed gene expression of the melanogenic proteins tyrosinase, tyrosinase-related protein (TYRP)-1 and microphthalmia-associated transcription factor, but not TYRP-2. The results support the utility of GA as an effective candidate antimelanogenic agent.

A New Papilla Preservation Technique for Periodontal Regeneration of Severely Compromised Teeth

IntroductionPeriodontal regeneration of hopeless teeth represents a major concern for clinicians, especially when these teeth are associated with the esthetic zone.Case PresentationThe case presented describes a non‐incised papillae surgical approach (NIPSA) to improve regenerative parameters in hopeless teeth. After treatment of a mandibular right canine with severe periodontal bone loss, clinical attachment loss to the apex, minimal keratinized tissue, and Class III mobility, there were important clinical improvements with no marginal soft tissue shrinkage and minimal morbidity for the patient.ConclusionNIPSA represents a promising minimally invasive technique even in hopeless teeth, facilitating the treatment of deep intrabony defects associated with high risk of soft tissue collapse and post‐surgical soft tissue shrinkage.

Reduced Bacterial Wilt in Tomato Plants by Bactericidal Peroxyacetic Acid Mixture Treatment.

Peroxyacetic acid mixture Perosan, composed of peroxyacetic acid, hydrogen peroxide and acetic acid, was evaluated for eco-friendly management of tomato bacterial wilt by Ralstonia pseudosolanacearum. Perosan drastically suppressed in vitro growth of R. pseudosolanacearum in liquid cultures in dose- and incubation time-dependent manners. Higher perosan doses (0.1 and 1%) caused lowered pH and phytotoxicity to detached leaves of two tomato cultivars Cupirang and Benekia 220 in aqueous solution. Treatment with 0.01% of Perosan delayed wilting symptom significantly in the detached leaves of two cultivars inoculated with R. pseudosolanacearum (107 cfu/ml). Soil drenching of 5% Perosan solution in pots caused severe tissue collapse of tomato seedlings at the four-week-old stage of two tomato cultivars. Treatment with 1% Perosan by soil-drenching significantly reduced bacterial wilt in the tomato seedlings of two cultivars. These findings suggest that Perosan treatment can be applied to suppress bacterial wilt during tomato production.

Antioxidant and proliferative activity of the fruit extract of Lycium chinense in regenerating liver after partial hepatectomy in rats

Objective: This study was carried out to evaluate the antioxidant activity and effect of a hot water extract of Lycium chinense fruit (LFE) on liver regeneration induced by Partial Hepatectomy (PH) in rats. Methods: Antioxidant activity of LFE was determined. Rats were divided into three groups; laparotomized (sham, n=15), 70% PH (control, n=25), and LFE-treated after PH (experimental, n=35). Starting 7 days before PH, rats received DW or LFE (500 mg/kg in DW) orally once a day until sacrifice. Rats were sacrificed on d 0.5, 1, 2, 3, and 7 after surgery. Liver regeneration ratio and Proliferating Cell Nuclear Antigen (PCNA) expression were determined through immunohistochemistry and western blotting. Results: Final extraction yield of LFE was 36.0%. LFE scavenged the DPPH and the ABTS radicals in a concentration-dependent manner. The IC50 of LFE on DPPH and ABTS antioxidant activity was 5.97 mg/ml and 2.53 mg/ml, respectively. The extent of liver regeneration seen in the experimental group (91.29%) at 7 d after PH was greater than that in the control group (89.43%). After PH, the liver reconstruction process involving collapse, re-arrangement and re-modelling of hepatic tissue was observed to happen sooner in the experimental group. The number of PCNA-positive hepatocytes obviously increased in the experimental group. PCNA-positive hepatocyte ratio peaked at 2 and 3 d in the experimental and control groups, respectively. Conclusions: Administration of LFE had beneficial effects on the regenerative capacity of remnant liver tissue after 70% PH in rats, probably owing to its antioxidant and proliferative properties.

Hyperhydricity-induced ultrastructural and physiological changes in blueberry (vaccinium spp.)

Hyperhydricity can cause significant economic loss for the micro-propagation industry that produces blueberry. In order to predict and control the occurrence of hyperhydricity, better understanding of the anatomical and physiological features of hyperhydric plantlets is required. In this study, we investigated the ultrastructural and physiological changes associated with hyperhydric blueberry plantlets. Compared to normal plantlets, hyperhydric plantlets exhibited reduced cell wall thickness, damaged membrane and guard cell structure, decreased number of mitochondria and starch granule, higher cell vacuolation, more intercellular spaces, and collapse of vascular tissues. In addition, excessive accumulation of reactive oxygen species (ROS) and ethylene, decreased stomatal aperture and water loss, as well as abnormity of stomatal movement were also evident in the hyperhydric plantlets. The results suggested that excessive ethylene and ROS produced in response to the stress arising from in vitro culture could lead to abnormal stomatal closure, causing the accumulation of water in the tissues. This would lead to subsequent induction of oxidative stress (due to hypoxia) and cell damage, especially guard cell structure, eventually giving rise to the symptoms of hyperhydricity. Reducing the content of ethylene and ROS, and protecting the structure and function of the stomata could be considered as potential strategies for inhibiting hyperhydricity or restoring the hyperhydric plants to their normal state.

First Report of Phytophthora Aerial Blight Caused by Phytophthora nicotianae on Vinca, Lobelia, and Calibrachoa in Ohio

Vinca (Catharanthus roseus), lobelia (Lobelia erinus), and calibrachoa (Calibrachoa × hybrida) are important edging and bedding plants to Ohio’s floriculture industry. In July 2015, Ohio State University’s C. Wayne Ellett Plant and Pest Diagnostic Clinic received plant samples of vinca cultivars Dark Red and Titan Burgundy, calibrachoa cultivar Konga Rose Kiss, and an unknown lobelia cultivar from a botanical garden in Hamilton County, Ohio, exhibiting symptoms of foliar blight, stem dieback, and collapse of the aboveground tissues. The samples were collected from spatially separated beds within the same garden, and disease incidence in each bed varied between 30 and 60%. The samples tested positive for Phytophthora using an ImmunoStrip test (Agdia). Isolations from the edge of leaf lesions onto pimaricin, ampicillin, rifampicin, and pentachloronitrobenzene-V8 medium (Ferguson and Jeffers 1999) consistently yielded typical Phytophthora spp. isolates. All subcultured isolates produced a nondescript growth pattern on lima bean agar (LBA) but a stoloniferous one on potato dextrose agar. Morphological characteristics of one representative isolate from each plant species were determined using 18-day-old colonies on LBA incubated at 22 to 23°C under continuous florescent light. Cultures were heterothallic and produced abundant chlamydospores, which were intercalary or terminal and measured 25.66 to 54 × 27.2 to 67.76 μm (n = 128). Sporangiophores were unbranched. Sporangia varied in shape from globose to ovoid, ellipsoid, or pyriform measuring 29.03 to 55.96 × 33.6 to 69.08 μm (n = 137), were papillate, occasionally bipapillate, and noncaducous. Papillae measured 5.06 to 7.88 × 7.17 to 11.67 μm (n = 90). Based on morphological characteristics, the pathogen was identified as Phytophthora nicotianae Breda de Haan (Erwin and Ribeiro 1996). The identity of isolates was confirmed through BLAST searches of their internal transcribed spacer region (ITS1-5.8S-ITS2) sequences (GenBank accession nos. MF471219, MF784254, and MF784255) in the Phytophthora-ID database, all resulting in 99% similarity with 100% coverage to P. nicotianae (accession no. AF266776). Pathogenicity of the three isolates was determined by spraying a 1 × 10⁴ to 9 × 10⁴ zoospores/ml solution until run-off, directly on the foliage of three of each of the respective hosts (10-week-old vinca cultivar Titan Burgundy, calibrachoa cultivar Crave Sunset, and 12-week-old lobelia cultivar Riviera Blue Eyes). Three control plants per species were sprayed with sterile distilled water. Following inoculation, plants were individually placed in plastic bags for 48 h and were kept in a greenhouse at a temperature of 23 to 24°C during the day and 19 to 22°C during the night. Leaf spots were observed on all inoculated plants in as little as 2 days. Leaf and shoot blight were observed after 4 to 5 days, whereas wilting developed after 10 days. Control plants remained asymptomatic. The pathogen was successfully reisolated and identified morphologically as described above, therefore fulfilling Koch’s postulates. Phytophthora nicotianae is one of the most common Phytophthora species attacking ornamental plants (Olson et al. 2013). The pathogen has been reported on vinca throughout the eastern United States and on calibrachoa in North Carolina (Lamour et. al. 2003; Olson and Benson 2011), but it has never been reported on lobelia in the United States. This is the first reported case of P. nicotianae infecting all three hosts in Ohio. Due to environmental characteristics, incidence of Phytophthora diseases is high in Ohio. This report contributes to increased awareness of the potential of new hosts for the pathogen to thrive on.

Barbed expansion sphincter pharyngoplasty for the treatment of oropharyngeal collapse in obstructive sleep apnoea syndrome: A retrospective study on 17 patients.

Expansion Sphincter Pharyngoplasty (ESP) was introduced in 2007 and represents a promising surgical technique to treat patients with oropharyngeal walls collapse with reduced morbidity and high success rates. Between December 2012 and January 2015 17 patients underwent ESP at the department of Otorhinolaryngology of the University of Brescia (Italy), using barbed knotless sutures to improve the biomechanical effect of sutures on tissue collapse (BESP). Patients with moderate to severe OSAS and BMI < 30 kg/m2, who did not tolerate or refused ventilation therapy, were selected for BESP based on the presence of oropharyngeal collapse, as determined by upper airway examination and drug-induced sleep endoscopy. Overall success of BESP was 94,1%. Postoperative oxygen desaturation index (ODI) showed significant improvement (P<0.01). Likewise, Epworth Sleepiness Scale score was significantly reduced (P<0.05). No patient complained of uncontrolled pain after the procedure and/or reported unsatisfactory analgesia at follow-up visits. Albeit limited by the sample size and duration of follow-up, our experience confirms the validity of BESP in this selected patient population. This article is protected by copyright. All rights reserved.

Phenotypic variation of thymic epithelial cells and partial spontaneous regression in thymoma of a cow

Thymoma was recognized in a 12-year-old Holstein dairy cow presenting with no significant clinical signs. The animal was conventionally slaughtered at an abattoir and, on postmortem examination, a spherical tumor mass was found in the anterior region of the mediastinum. Histologically, the tumor was fibrously encapsulated and exhibiting varying-sized cystoid cavities containing serous fluid and necrotic and hemorrhagic foci. No architectural features showing distinct characteristics to a sufficient degree to allow identification of the thymus or other organs could be seen. The tumor showed diffuse solid sheet-like or nodular patterns of proliferation and consisted of a dual cell population: one was neoplastic epithelial cells that were immunohistochemically positive for cytokeratin, and the other was T lymphocytes that exhibited positive immunohistochemical staining with CD3. This finding enabled a diagnosis of mixed thymoma to be made. Neoplastic epithelial cells represented a wide spectrum of phenotypic expression, including (1) spindle shaped cells with a chiasmus-like, interlacing fascicular, or storiform growth pattern; (2) small, round to oval cells with scant cytoplasm showing indistinct boundary of cells; (3) large cells arranged in a solid sheet-like pattern; (4) vacuolated cells similar to signet ring cells; (5) clear cells that had defined cell membranes; and (6) occasional formation of micronodules composed of neoplastic epithelial cells. In addition, some areas of the tumor exhibited features of partial spontaneous regression characterized by collapse or disintegration of tumor tissues in close association with fibrocollagenous connective tissue deposition. Even if the morphology of thymic epithelial cells in thymoma is known to display variable appearance, it is likely to be unusual that, in the current bovine case, such thymic epithelial cells exhibited a wider spectrum of phenotypic expression within a single tumor. This salient histomorphological heterogeneity shown by thymic epithelial cells might have presumably been associated with innate characteristics specific to pluripotent thymic epithelial cells during thymoma tumorigenesis.

Increased microRNA-93-5p inhibits osteogenic differentiation by targeting bone morphogenetic protein-2.

Background and purposeTrauma-induced osteonecrosis of the femoral head (TIONFH) is a major complication of femoral neck fractures. Degeneration and necrosis of subchondral bone can cause collapse, which results in hip joint dysfunction in patients. The destruction of bone metabolism homeostasis is an important factor for osteonecrosis. MicroRNAs (miRNAs) have an important role in regulating osteogenic differentiation, but the mechanisms underlying abnormal bone metabolism of TIONFH are poorly understood. In this study, we screened specific miRNAs in TIONFH by microarray and further explored the mechanism of osteogenic differentiation.DesignBlood samples from patients with TIONFH and patients without necrosis after trauma were compared by microarray, and bone collapse of necrotic bone tissue was evaluated by micro-CT and immunohistochemistry. To confirm the relationship between miRNA and osteogenic differentiation, we conducted cell culture experiments. We found that many miRNAs were significantly different, including miR-93-5p; the increase in this miRNA was verified by Q-PCR. Comparison of the tissue samples showed that miR-93-5p expression increased, and alkaline phosphatase (ALP) and osteopontin (OPN) levels decreased, suggesting miR-93-5p may be involved in osteogenic differentiation. Further bioinformatics analysis indicated that miR-93-5p can target bone morphogenetic protein 2 (BMP-2). A luciferase gene reporter assay was performed to confirm these findings. By simulating and/or inhibiting miR-93-5p expression in human bone marrow mesenchymal stem cells, we confirmed that osteogenic differentiation-related indictors, including BMP-2, Osterix, Runt-related transcription factor, ALP and OPN, were decreased by miR-93-5p.ConclusionOur study showed that increased miR-93-5p in TIONFH patients inhibited osteogenic differentiation, which may be associated with BMP-2 reduction. Therefore, miR-93-5p may be a potential target for prevention of TIONFH.

Alveolar Bone Preservation. Biological Basis and Techniques

Tooth extraction or tooth loss can often result in both alveolar ridge resorption and soft tissue collapse. Preservation of bone volume and soft tissue height at the time of tooth extraction is an important procedure that can facilitate various treatment approaches specially implant placement and ensure that proper restorative goals are met. Proper management of extraction sites at the time of tooth extraction can reduce or eliminate the future need for advanced ridge augmentation procedures prior to implant placement. In addition, poor extraction site management may lead to esthetic and functional prosthetic complications.