Subepithelial Thickness Research Articles

The effect of adipose tissue-derived stromal vascular fraction/gel material on wound healing in a rat model of nasal mucosa injury

Background Stromal Vascular fraction/gel (SVF/gel) is prepared mechanically from autologous adipose tissue, and it is known for its regenerative and anti-inflammatory properties. Aims To assess histopathological effects of adipose tissue-derived SVF/gel and nasal steroids on nasal mucosal healing Material and Methods Forty-two Wistar Albino rats with right nasal mucosal injury were randomly divided into three groups: control (saline), Mometasone Furoate (MF), and SVF/gel. Control group (n = 14) received saline for 7 days, while MF group (n = 14) was administered MF to the right nasal cavity for 7 days. SVF/gel group (n = 14) was treated once with SVF/gel in the right nasal cavity. Histological analysis on days 14 and 28 post-injury focused on evaluating epithelial thickness, inflammation, disarray, subepithelial thickness, goblet cell count, subepithelial fibrosis, presence of ciliated cells, lacunae, adhesion, and neo-osteogenesis. Results When comparing the MF and SVF/gel groups, statistically significant differences were found on day 14 in indices of epithelial thickness, subepithelial thickness, goblet cells, subepithelial fibrosis, and ciliated cells. On day 28, SVF/gel group exhibited higher ciliated cell counts and lower subepithelial fibrosis values (p = .027; p = .016). Additionally, epithelial disarray, adhesions, lacunae, and neo-osteogenesis were not observed in the SVF/gel group. Conclusions and Significance SVF/gel accelerates re-epithelialization, reduces fibrosis and adhesions, and enhances cilia formation compared to nasal steroids. These findings suggest that SVF/gel is an autologous and cost-effective treatment for improving nasal mucosal healing post-injury.

Nasal Packing Materials and Placement Duration on Wound Healing in Nasal Mucosa: An Animal Study.

The histological findings of wound healing depending on different nasal packing materials and replacement periods were lacking. Mucosal defects were created in the nasal septum of rabbits and covered with Spongel®, Algoderm®, or Nasopore®, which were cleaned on Day 14. To investigate the effect of replacement durations, Spongel® was removed on Days 3 and 7. All nasal septal specimens were collected on Day 28. Samples without packing material were prepared as controls. Depending on residual packing materials in the regenerated tissue, specimens were classified into the remnant and non-remnant groups, and morphology was compared using epithelium grade score and subepithelial thickness. The epithelium grade score in the Spongel-14d group was lower than that in the other groups (p < 0.05). Subepithelial thickness was higher in the Algoderm-14d and Spongel-14d groups (p < 0.05). Epithelium grade scores were higher and subepithelial thicknesses were lower in the Spongel-3d and -7d groups than in the Spongel-14d group. Epithelium grade score was lower and subepithelial thickness was higher in the remnant group (n = 10) than in the non-remnant group (n = 15; p < 0.05). Differences in packing materials and placement durations affected wound healing of nasal mucosa. The selection of appropriate packing materials and replacement duration was considered essential for ideal wound healing. NA Laryngoscope, 134:562-568, 2024.

A RAS inhibitor reduces allergic airway remodeling via regulating IL-33-derived type 2 innate lymphoid cells

Purpose: IL-33 is known to induce corticosteroid-resistant eosinophilic inflammation and airway remodeling by activating type 2 innate lymphoid cells (ILC2s). Although the RAS signal pathway plays an important role in IL-33-induced ILC2s activation and airway remodeling, it is not known if RAS inhibitors are effective against refractory asthma. We examined the effects of the RAS inhibitor XRP44X in refractory asthma. Methods: RAS activity were examined by BAL fluid and T-cells isolated from spleen cells in Dermatophagoides pteronyssinus (Dp)-sensitized/challenged acute allergic airway inflammation model. A chronic allergic airway inflammation mouse model was generated by challenged with Dp. XRP44X and/or fluticasone were administrated nasally to different experimental groups. The effects of nasal simultaneous administration of XRP44X or fluticasone were assessed in mice administrated with IL-33 or Dp. Results: RAS activity in CD4+ T cells stimulated by Dp were suppressed by XRP44X. Although fluticasone and XRP44X only improved allergic airway inflammation in mice, XRP44X in combination with fluticasone produced further improvement in not only eosinophilic inflammation but also bronchial subepithelial thickness. XRP44X suppressed IL-5 and IL-13 production from ILC2s, although this effect was not suppressed by fluticasone. IL-33-induced airway inflammation resistant to fluticasone was ameliorated by XRP44X via regulating the accumulation of lung ILC2s. Conclusion: The RAS signal pathway plays a crucial role in allergen-induced airway remodeling associated with ILC2s. XRP44X may have therapeutic potential for refractory asthma.

The Effects of Postoperative Astaxanthin Administration on Nasal Mucosa Wound Healing.

Background: Wound healing of the nasal mucosa after endoscopic sinus surgery (ESS) is frequently complicated by scaring and consequently recurrences are encountered. Methods of optimizing results have been sought. In the present study we evaluated the effects of a powerful antioxidant, astaxanthin, on nasal mucosa healing after surgery, comparing it to the extensively studied properties of dexamethasone. Materials and Methods: 63 Wistar rats were used. The nasal mucosa from one side was damaged employing the brushing method. They were randomly divided into three experimental groups, one treated with astaxanthin, the second treated with dexamethasone and the third one acted as the control and was given normal saline. The rats were killed on days 5, 14 and 28 following injury. We observed the temporal evolution of the wound healing process and quantified the results by assessing four parameters: the epithelial thickness index (ETI), the subepithelial thickness index (STI), the goblet cell count and the subepithelial fibrosis index (SFI). Results: At 28 days, the ETI was significantly lower in the astaxanthin group (p < 0.05) compared to the other two groups. The STI was also lower in the astaxanthin group (p < 0.05), but comparable to the dexamethasone group at 28 days. The goblet cell count was higher in the astaxanthin group. The SFI had similar results in both dexamethasone and astaxanthin groups, with lower values compared to the control group. In the astaxanthin group there was no synechia formation. Conclusion: Astaxanthin given in the post injury period significantly decreases fibrosis, inhibits synechia development and significantly decreases subepithelial fibrosis. Moreover, it has no general or local toxic effects.

The Effects of Halofuginone on Wound Healing in the Rat Nasal Mucosa.

Background Halofuginone is an alkaloid febrifugine analogue and bioactive molecule that was isolated incidentally from the Dichroa febrifuga plant. The therapeutic efficacy of halofuginone in parasitic infections, scleroderma, inflammation, and fibrosis-related diseases, as well as in some types of cancer, has been previously reported. The effects of halofuginone on nasal mucosal damage are not yet known. Objective The aim of this study was to investigate the potential effect of topically applied halofuginone on wound healing in the mechanically injured nasal mucosa of rats. Methods A unilateral mucosal wound was created in the nasal cavity of 32 rats (aged 4 weeks) using the brushing technique. These rats were randomly divided into 4 groups. Although the control group did not receive an intervention, a dry pad, a saline-impregnated pad, or a pad impregnated with halofuginone were placed in the rats of the other 3 groups and left for 5 minutes. Rats were sacrificed on the 14th day, and a histological examination was performed. The nasal mucosa was assessed via hematoxylin-eosin and Masson’s trichrome staining. Results There were no statistically significant differences in epithelial thickness, inflammation, goblet cell formation, and epithelial disarray values between the halofuginone group and the control group ( P &gt; .05). The subepithelial thickness was significantly decreased in the saline-treated group and the halofuginone-treated group ( P &lt; .05), but a significantly lower level of subepithelial fibrosis was only observed in the halofuginone group compared to the other groups ( P &lt; .05). Conclusions Topical halofuginone administration reduces the development of fibrosis and subepithelial edema after experimentally induced nasal mucosal injury, but it does not exert therapeutic or preventive effects on epithelial damage, inflammation, and goblet cell hyperplasia.

Effects of Oral Propolis on Mucosal Wound Healing after Endoscopic Nasal Surgery in a Rabbit Model.

If the respiratory nasal mucosa is damaged and the mucosa does not heal properly during nasal or paranasal sinus surgery, a revision surgery may be required. The aim of this study is to investigate the effects of oral propolis application on mucosal wound healing following endoscopic nasal surgery in a rabbit model. Twenty four New Zealand rabbits were randomly divided into three groups, namely the experimental group (EG), the control group (CG), and the negative control group (NCG). Mucosal resection was applied with 3-mm punch forceps in the bilateral ventral nasal concha in the experimental and control groups. 75 mg/kg/day propolis was added to the diet of the rabbits in the EG for 14 days. The CG continued with the standard diet postoperatively. In the NCG, no surgical intervention was made, and no dietary support was given. On postoperative day 14 all rabbits were sacrificed and left nasal specimens were examined histopathologically, hydroxyproline levels were measured in right nasal specimens. There were no statistically significant differences in hydroxyproline level, epithelial and subepithelial thickness, ciliary and goblet cell count, subepithelial fibrosis and collagen density between EG and CG. Neutrophil count was statistically significantly lower in EG, compared to CG (p=0.019, Tamhane test). Although there are many studies that show the positive effects of propolis on wound healing, such effect was not observed in this study. This study is deemed to constitute a unique experimental study that can be a resource for future similar studies to be performed with higher numbers of subjects and higher dosage of propolis.

Herbal dry extract BNO 1011 improves clinical and mucociliary parameters in a rabbit model of chronic rhinosinusitis.

Enhancing chloride (Cl- ) secretion in sinus epithelia represents a novel therapeutic approach to chronic rhinosinusitis (CRS). Herbal dry extract BNO 1011 enhances mucociliary clearance (MCC) via upregulation of Cl- secretion in sinonasal cultures in vitro and murine epithelium in vivo. The objective of this study is to evaluate whether the BNO 1011 improves MCC and clinical parameters in a rabbit model of CRS. After the development of CRS in 30 New Zealand white rabbits, animals were randomly assigned to receive oral placebo (n = 10), BNO 1011 (low dose [LD], 25 mg/kg/daily) (n = 10), or BNO1011 (high dose [HD], 125 mg/kg/daily) (n = 10) for 4 weeks. Outcomes included sinus opacification (Kerschner's rabbit sinus CT grade), maxillary epithelial Cl- secretion (sinus potential difference [PD] assay), airway surface liquid (ASL) depth using micro-optical coherence tomography (μOCT), and submucosal gland density (SMD) on histopathology. Outcome parameters were analyzed by 2 blinded investigators. BNO 1011 significantly cleared sinus opacification (HD = 1.21 ± 0.63, LD = 1.26 ± 0.37,) compared to placebo (4.02 ± 0.92) (p = 0.009). BNO 1011 resulted in markedly greater mean sinus PD polarization (HD = -12.23 ± 1.4 mV, LD = -12.0 ± 3.0 mV) when compared to rabbits treated with placebo (-4.1 ± 1.1 mV) (p = 0.03). ASL depth was significantly improved when treated with HD (4.08 ± 0.06 μm) and LD (4.05 ± 0.06 μm) compared to placebo (3.5 ± 0.05 μm) (post hoc analysis, p < 0.0001). Histologically, epithelial thickness (HD = 10.0 ± 0.7 μm; LD = 13.7 ± 0.9 μm; placebo = 21.1 ± 2.3 μm; p < 0.005), subepithelial thickness (HD = 63.1 ± 6.6 μm; LD = 103.2 ± 6.7 μm; placebo = 113.3 ± 6.0 μm; p < 0.001), and SMD (HD = 22.2 ± 2.9%; LD = 31.8 ± 1.1%; placebo = 43.8 ± 1.7%; p < 0.0001) were noticeably better with the HD. Herbal dry extract BNO 1011 improves radiographic, histologic, and MCC parameters in a rabbit model of CRS.

Potential Curative Role of Hypericum Perforatum in an Experimental Rat Model of Tympanic Membrane Perforation.

Our aim was to investigate the curative role of topical Hypericum perforatum (HP) in a rat model of tympanic membrane perforation in a histopathological manner. This study was conducted on 30 female Sprague-Dawley rats. An HP extract was prepared as a suspension in pure olive oil. In all rats, the right and left tympanic membranes were perforated by a fine puncture under a microscope. Rats were randomly assigned to three groups. The HP extract was given as drops on a daily basis in Group 1, while olive oil alone was given on a daily basis in Group 2. In Group 3, the rats were allowed spontaneous recovery without any intervention. Three rats from each group were sacrificed on days 7, 14, and 21. Temporal bullae were removed for histopathological examination to evaluate fibroblast proliferation, leukocyte infiltration, neovascularization, and subepithelial thickness and to compare these among the groups. In histopathological examination of the rats from each group on days 7, 14, and 21, there were significant differences in leukocyte infiltration, fibroblast proliferation, and subepithelial thickness. No significant difference was observed in neovascularization among the groups. Compared with the spontaneous recovery group, HP was found to be more effective in a wound-healing model of the tympanic membrane. HP may be applied in clinical practice if it is shown to be safe with regard to ototoxicity.

The staphylococcal enterotoxin burden determines the ultrastructure of ciliated epithelia and inflammatory changes in maxillary sinus mucosa of rabbits

To investigate the ultrastructure of ciliated epithelia and inflammatory changes upon repeated exposure to staphylococcal enterotoxin A (SEA) of different concentrations in the maxillary sinus mucosa of rabbits. The rabbits were randomly divided into 2 groups (24 rabbits per group): low-dose SEA group and high-dose SEA group. The low-dose SEA group and high-dose SEA group received daily injections of 0.6 ng of SEA (2 ml) and 60 ng of SEA (2 ml) into the left maxillary sinus of rabbits for 28 days, respectively. Concurrent treatment of the right maxillary sinus with normal saline was used as control. Six rabbits chosen randomly in two groups were examined by computed tomography (CT) scans and then sacrificed to obtain the sinus mucosa from the two-side of maxillary sinuses for histological assessment on days 3, 7, 14 and 28. To characterize the inflammatory changes of the sinus mucosa examined using light microscope, hematoxylin and eosin (HE) and toluidine blue staining was performed. Scanning and transmission electron microscopy were performed to observe ultrastructure of ciliated epithelia in the maxillary sinus mucosa. SPSS 13.0 software was used to analyze the data. On days 14 and 28, CT images showed opacification of the left maxillary sinus in the high-dose SEA group. The percentage of epithelial disruption was (22.73 ± 5.72) % and (30.79 ± 4.30)% in the high-dose SEA group respectively, and were significantly greater than those in the low-dose SEA group (5.12% ± 1.98% and 5.38% ± 1.64%, q value was 10.079 and 19.132) and control group (4.08% ± 1.29% and 4.81% ± 1.62%, q value was 11.016 and 19.592, respectively, all P < 0.01). The subepithelial thickness in the high-dose SEA group was (113.34 ± 14.81)µm and (120.86 ± 12.35) µm respectively, and were significantly different from those of the low-dose SEA group [(71.08 ± 10.39)µm and (81.63 ± 9.32)µm, q value was 8.090 and 8.782] and control group [(37.45 ± 7.67)µm and (38.79 ± 7.68)µm, q value was 15.759 and 19.541, all P < 0.01]. Viewed under the electron microscope, loss of cilia was observed, a few compound cilia and cytoplasmic protrusion were found, an obvious stretching of the endoplasmic reticulum and an obvious turgescence of the mitochondria was also observed. However, in the low-dose SEA group on days 14 and 28, CT scan of the left maxillary sinus showed transparency; light microscopy observations of the maxillary sinus mucosa showed the number of eosinophils was markedly increased as compared with the high-dose SEA and control groups, the differences were significant (q value was 5.871 and 6.766 on day 14, and q value was 7.572 and 8.970 on day 28, respectively, all P < 0.05). But no significant differences were observed in epithelial disruption between the low-dose SEA and the control groups on days 14 and 28 (q value was 1.512 and 0.859 respectively, all P > 0.05); inordinate array and adhesion of cilia was observed, but cilia loss, compound cilia, cytoplasmic protrusions, mitochondrial swelling and endoplasmic reticulum stretching were not found. SEA may induce allergic inflammation of the sinus mucosa without damaging the structure of ciliated epithelia at low concentration. Whereas SEA impairs the structure of mitochondria and endoplasmic reticulum in ciliated epithelial cells at high concentration, and results in cilia loss and epithelial disruption, which may be one of the main reasons to induce acute sinusitis.

Effects of caffeic acid phenethyl ester on wound healing of nasal mucosa in the rat: an experimental study

PurposeWound healing of the nasal mucosa is a highly complex process that restores the anatomical and functional integrity of tissue that has been exposed to trauma. In this experimental study, our aim was to use histopathological examination to investigate the effects of caffeic acid phenethyl ester on the wound healing of rat nasal mucosa after mechanical trauma. Materials and methodsThe rats were randomly divided into 3 experimental groups: a non-treated group (n=7), a control saline group (n=7) and a caffeic acid phenethyl ester group (n=7). The non-treated group received no treatment for 15days. The second group was administered saline (2.5mL/kg, intraperitoneal) once a day for 15days. The third group received caffeic acid phenethyl ester intraperitoneally at a dose of 10μmol/kg once a day for 15days. At the beginning of the study, unilateral mechanical nasal trauma was induced on the right nasal mucosa of all rats in the three groups using a brushing technique. Samples were stained using hematoxylin and eosin solution and were examined by a pathologist using a light microscope. ResultsThe severity of inflammation was milder in the caffeic acid phenethyl ester group compared with that in the non-treated and saline groups (P<0.05). The subepithelial thickness index was lower in the experimental group (P<0.05). Goblet cell and ciliated cell loss was substantially reduced in the experimental group compared with the non-treated and saline groups (P<0.05). ConclusionsCaffeic acid phenethyl ester decreases inflammation and the loss of goblet cells and ciliated cells. Therefore, caffeic acid phenethyl ester has potential beneficial effects on the wound healing of nasal mucosa in the rat.

Extra domain-A fibronectin is necessary for the development of nasal remodeling in chronic allergen-induced rhinitis

BackgroundExtra domain A–containing fibronectin (EDA-FN) is necessary for the development of allergen-induced lower airway fibrosis. The pathogenesis of fibrosis in allergic rhinitis has not been well studied. ObjectivesTo determine whether EDA-fibronectin is necessary for the development of nasal remodeling in a murine model of chronic allergic rhinitis and in human allergic rhinitis. MethodsEDA(-/-) and wild-type (WT) C57Bl/6 mice were sensitized intraperitoneally and then challenged with inhaled ovalbumin (OVA) or saline for 2 and 5 weeks. Clinical signs of rhinitis and histological analysis of nasal tissue were evaluated. Immunohistological staining for EDA-FN was performed in human tissue of inferior nasal conchae from patients with allergic rhinitis and controls. ResultsAfter 2 weeks of allergen exposure, only goblet cell hyperplasia and perivascular eosinophilia were observed. After 5 weeks, goblet cell number, thickening of the subepithelial layer, and extent and area of collagen deposition were increased in the nasal tissue of WT OVA (ovalbumin)-challenged mice as compared with saline controls (P < .0001, P < .0001, P = .018, and P = .03, respectively). Clinical signs of rhinitis were observed only in WT OVA-challenged mice. In the EDA(-/-) mice exposed to OVA, collagen deposition, collagen area, and subepithelial thickness showed no increase and were similar to saline control mice, whereas goblet cell hyperplasia was similar to WT OVA-challenged mice. EDA-FN expression was prominent in inferior conchae from patients with allergic rhinitis but was absent in control patients. ConclusionEDA-containing fibronectin is necessary for the development of nasal tissue fibrotic remodeling process in both murine and human allergic rhinitis.

A Time Course Study on the Development of Allergen-induced Nasal Airway Remodeling in a Rat Model

Only a few studies have investigated the airway remodeling process in allergic rhinitis (AR), and the results reported are conflicting. We established an allergen-induced nasal remodeling model for AR using brown Norway rats and investigated time-dependent histological changes and the reversibility of the epithelial and subepithelial changes. Ovalbumin (OVA)-sensitized rats were exposed to OVA daily and then assigned to one of five groups depending on the duration of the challenge. Groups I, II, III, and IV rats were exposed for 1, 4, 8, and 12 weeks, respectively. Group V rats were exposed for 12 weeks and then protected from challenge for 4 weeks. Matched control rats were exposed to saline. Histological parameters of the nasal mucosa such as epithelial and subepithelial thickness, goblet cell hyperplasia, eosinophil infiltration, submucosal gland hypertrophy, and expression of matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of metalloproteinase-1 (TIMP-1) were compared between groups. Repeated challenges for 12 weeks resulted in the characteristic features of nasal airway remodeling. All parameters except epithelial thickness increased markedly. Goblet cell hyperplasia and eosinophil infiltration decreased to control group levels after cessation of challenge for 4 weeks. Subepithelial changes such as subepithelial thickening, submucosal gland hypertrophy, and increased expression of MMP-9 and TIMP-1 were still observed after 4 weeks without challenge. Our results indicate that prolonged OVA challenge can induce nasal remodeling. Epithelial changes were minimal or absent after cessation of the challenge, but subepithelial changes were resistant to reversal.

Combination therapy with relaxin and methylprednisolone augments the effects of either treatment alone in inhibiting subepithelial fibrosis in an experimental model of allergic airways disease

Although CSs (corticosteroids) demonstrate potent effects in the control of airway inflammation in asthma, many patients continue to experience symptoms and AHR (airway hyper-responsiveness) despite optimal treatment with these agents, probably due to progressive airway remodelling. Identifying novel therapies that can target airway remodelling and/or airway reactivity may improve symptom control in these patients. We have demonstrated previously that the anti-fibrotic hormone RLN (relaxin) can reverse airway remodelling (epithelial thickening and subepithelial fibrosis) and AHR in a murine model of AAD (allergic airways disease). In the present study, we compared the effects of RLN with a CS (methylprednisolone) on airway remodelling and AHR when administered independently or in combination in the mouse AAD model. Female mice at 6-8 weeks of age were sensitized and challenged to OVA (ovalbumin) over a 9-week period and treated with methylprednisolone, RLN, a combination of both treatments or vehicle controls. Methylprednisolone was administered intraperitoneally on the same day as nebulization for 6 weeks, whereas recombinant human RLN-2 was administered via subcutaneously implanted osmotic mini-pumps from weeks 9-11. RLN or methylprednisolone alone were both able to significantly decrease subepithelial thickness and total lung collagen deposition; whereas RLN but not methylprednisolone significantly decreased epithelial thickness and AHR. Additionally, combination therapy with CS and RLN more effectively reduced subepithelial collagen thickness than either therapy alone. These findings demonstrate that RLN can modulate a broader range of airway remodelling changes and AHR than methylprednisolone and the combination of both treatments offers enhanced control of subepithelial fibrosis.

Effect of Dexamethasone on Wound Healing of the Septal Mucosa in the Rat

Postoperative treatment after functional endoscopic sinus surgery (FESS) aims to modulate the wound healing process. Systemic or topically applied corticosteroids have been reported to be beneficial for improving nasal wound healing after FESS. However, few studies have investigated the effects of postoperative systemic steroids on nasal wound healing with regard to histological changes. The aim of this study was to evaluate the effect of systemic dexamethasone on nasal wound healing after mechanical injury in the rat. A unilateral wound in the nasal cavity was induced using the brushing technique in 4-week-old, Sprague-Dawley rats (n = 70). Dexamethasone (0.15 mg/kg daily for 7 days) and normal saline were administered i.p. to the experimental and control groups (n = 35 for each) after the injury. The rats (n = 7 for each) were killed on days 2, 5, 14, 28, and 42 after the injury. Histological changes in the nasal mucosa were examined and compared using hematoxylin and eosin and Masson's trichrome staining. The experimental group showed less subepithelial edema formation and epithelial disarray at the early phase of the wound healing period. There were statistically significant differences in the subepithelial thickness and epithelial thickness indices between the experimental and control groups (p < 0.05). Ciliary and goblet cell indices were lower in the experimental group, which means that ciliary and goblet cell regeneration may be delayed by dexamethasone (p < 0.05). There were no differences in the subepithelial fibrosis index between the two groups. Adhesion formation between the nasal septum and turbinate were found only in the control group. Systemic dexamethasone after mucosal injury may lessen subepithelial edema, goblet cell hyperplasia, and adhesion formation; however, it may cause delayed mucosal ciliary regeneration.

Wound Healing of Nasal Mucosa in a Rat

Postoperative wound healing of the nasal mucosa is a highly organized process. However, this process still has not been fully understood. The present study aimed to establish a wound healing model in a rat and describe histomorphological changes of the nasal mucosa after mechanical injury. Unilateral wound in the nasal cavity was induced using the brushing technique in 4-week-old, Sprague-Dawley rats. Experimental rats were divided into five groups (n = 7 for each group). Animals were killed 1 hour and 2, 5, 14, and 28 days after injury. The histological sections were examined for inflammatory cell infiltration, goblet, and ciliated cell formation in hematoxylin and eosin staining. The subepithelial and epithelial thicknesses were measured and expressed as the subepithelial thickness index (STI) and epithelial thickness index (ETI). Fibrosis was evaluated by subepithelial fibrosis index (SFI) in Masson's trichrome-stained sections. Respiratory epithelial discontinuity and hemorrhage were observed 1 hour after injury. On day 2, edematous subepithelium and infiltration of neutrophils could be found on the injured site. Day 5 was characterized by the infiltration of monocytes and granulation tissue. SFI and ETI values increased significantly at day 14. Goblet cells and ciliated cells began to regenerate from day 14 and restored to near normal at day 28. Using mechanical injury, the wound healing model of the nasal mucosa was established in a rat. The regeneration of respiratory mucosa was completed on day 28 after injury.

Women’s health—what’s new worldwide

Women’s health—what’s new worldwide

Relationship Between Vascularity and Other Remodeling Parameters in Asthmatic Airway

Background The pathological features in asthmatic airway remodeling are diverse. The aim of this study was to examine the degree of airway vascularity in relation to the other remodeling parameters in asthmatics. Methods Bronchial biopsies were done in 34 asthmatic patients, and 6 control subjects. The basement membrane thickness and the subepithelial thickness were measured in the hematoxylin-eosin stained tissue, and the degree of vascularity was measured using type IV collagen immunostaining. Results 1) Compared to the control subjects, the asthmatics showed a significant increase in the basement membrane thickness (6.92±2.01µm vs 9.67±2.84µm, p<0.05) and the subepithelial thickness (44.49±31.92µm vs 121.22±72.79µm, p<0.05). 2) Compared to the control subjects, the asthmatics showed a significant increase in the vascular area per unit submucosal area (4.51±2.13% vs 10.32±6.08%, p<0.05). In addition, the number of vessels per unit submucosal area showed an increased tendency without statistical significance. 3) In the asthmatics, the number of vessels and the vascular area per unit submucosal area showed no correlation with the basement membrane thickness, the subepithelial thickness, the severity, the forced expiratory volume in 1 second(FEV1), and the methacholine provocative concentration 20(PC20). Conclusion This study showed that vascularity was an important parameter in asthmatic airway remodeling but it was not related to the other remodeling parameters such as the basement membrane thickness and the subepithelial thickness. Each of these asthmatic remodeling parameters may have a different clinical significance. Therefore, further studies will be needed.

Effect of cryopreservation period on rat tracheal allografts

Background: The effect of cryopreservation on tracheal allogenicity is still unclear. Therefore, in this study, we assessed the effect of cryopreservation period on tracheal allografts in 62 rats. Methods: Each transplant consisted of a 3-ring segment of the trachea harvested from 8 Lewis rats, immersed in preservation solution, and cryopreserved and stored in a Bicell biofreezing vessel in a deep freezer at −80°C. Six tracheal grafts without cryopreservation that underwent a heterotopically syngeneic transplantation into the omentum served as controls. Forty-eight tracheal segments were randomly assigned to 8 groups according to period of cryopreservation, which ranged from 0 to 12 months (0, 0.5 [2 weeks], 1, 2, 3, 6, 9 and 12 months). The cryopreserved grafts were then thawed and heterotopically implanted into the omentum of recipient Brown-Norway rats. After 28 days, the tracheal segments were then evaluated histologically. Results: All isografts in Group 1 were intact, whereas the allografts undergoing a particularly shorter period of cryopreservation showed a more stenotic lumen. Prolonged periods of cryopreservation tended to show decreasing tendencies of viability of chondrocytes, mononuclear cell infiltration and sub-epithelial thickness, whereas all allografts showed a uniformly denuded epithelium, irrespective of the length of cryopreservation. Conclusions: A longer period of cryopreservation may help to maintain a better patency of tracheal allografts by preventing an allogeneic response. Reduced tracheal allogenicity may be associated with a decreased viability of chondrocytes by cryopreservation.

Balance in asthma between matrix metalloproteinases and their inhibitors

Balance in asthma between matrix metalloproteinases and their inhibitors