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1.
Defects of the cystic fibrosis (CF) transmembrane conductance regulator (CFTR) protein affect the homeostasis of chloride, bicarbonate, sodium, and water in the airway surface liquid, influencing the mucus composition and viscosity, which induces a severe condition of infection and inflammation along the whole life of CF patients. The introduction of CFTR modulators, novel drugs directly intervening to rescue the function of CFTR protein, opens a new era of experimental research. The review summarizes the most recent advancements to understand the characteristics of the infective and inflammatory pathology of CF lungs. 相似文献
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Spinster 2 (Spns2) is a transporter that pumps sphingosine-1-phosphate (S1P), a bioactive lipid mediator synthesized in the cytoplasm, out of cells into the inter cellular space. S1P is a signal that modulates cellular behavior during embryonic development, inflammation and tissue repair, etc. A Spns2-null (KO) mouse is born with failure of eyelid closure (eyelid-open-at birth; EOB) and develop corneal fibrosis in adulthood. It remains elusive whether corneal lesion is caused by exposure to keratitis (lagophthalmos) of EOB phenotype or the loss of Spns2 directly perturbs the corneal tissue morphogenesis and intra-eyelid structures. Therefore, we investigated differences between the cornea and ocular adnexa morphogenesis in KO and wild-type (WT) embryos and adults as well.The loss of Spns2 perturbs cornea morphogenesis during embryonic development as early as E16.5 besides EOB phenotype. Histology showed that the corneal stroma was thinner with less extracellular matrix accumulation, e.g., collagen and keratocan in the KO mouse. Epithelial stratification, expression of keratin 12 and formation of desmosomes and hemidesmosomes were also perturbed in these KO corneas. Lacking Spns2 impaired morphogenesis of the Meibomian glands and of orbicularis oculi muscles. KO glands were labeled for ELOVL4 and PPARγ and were Oil-Red O-positive, suggesting KO acinar cells possessed functionality as the glands.This is the first report on the roles of Spns2 in corneal and Meibomian gland morphogenesis. Corneal tissue destruction in an adult KO mouse might be due to not only lagophthalmos but also to an impaired morphogenesis of cornea, Meibomian glands, and orbicularis oculi muscle. 相似文献
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PurposeTo assess the prediction of the response to photodynamic therapy (PDT) in chronic central serous chorioretinopathy (CSCR) based on spectral-domain optical coherence tomography (SD-OCT) images using deep learning (DL).MethodsRetrospective study including 216 eyes of 175 patients with CSCR and persistent subretinal fluid (SRF) who underwent half-fluence PDT. SD-OCT macular examination was performed before (baseline) and 3 months after treatment. Patients were classified into groups by experts based on the response to PDT: Group 1, complete SRF resorption (n = 100); Group 2, partial SRF resorption (n = 66); and Group 3, absence of any SRF resorption (n = 50). This work proposes different computational approaches: 1st approach compares all groups; 2nd compares groups 1 vs. 2 and 3 together; 3rd compares groups 2 vs. 3.ResultsThe mean age was 55.6 ± 10.9 years and 70.3% were males. In the first approach, the algorithm showed a precision of up to 57% to detect the response to treatment in group 1 based on the initial scan, with a mean average accuracy of 0.529 ± 0.035. In the second model, the mean accuracy was higher (0.670 ± 0.046). In the third approach, the algorithm showed a precision of 0.74 ± 0.12 to detect the response to treatment in group 2 (partial SRF resolution) and 0.69 ± 0.15 in group 3 (absence of SRF resolution).ConclusionDespite the high clinical variability in the response of chronic CSCR to PDT, this DL algorithm offers an objective and promising tool to predict the response to PDT treatment in clinical practice. 相似文献
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Salum FG Cherubini K de Figueiredo MA Amado Mde O Rodrigues ET Yurgel LS 《Clinical oral investigations》2006,10(3):211-215
The present study was conducted to investigate the effect of topical thiocyanate (SCN−) application on hamster cheek pouch mucosa. Sixty-six hamsters were divided into two groups. The test substance containing potassium thiocyanate was applied on the hamsters’ cheek pouches at 55 mg/kg dosages. Cheek pouches were grossly examined after 12 weeks. Histometric evaluation included height measurements from the epithelium without stratum corneum, stratum corneum, and full epithelium. Clear cells frequency was compared between groups. Results were analyzed using Student’s t test. The experimental group showed a lower height of the stratum corneum (p=0.035) and higher frequency of clear cells (p<0.001). There was no height difference for the epithelium without stratum corneum (p=0.677) and full epithelium (p=0.904) between groups. SCN− promotes no gross alterations on hamsters’ cheek pouch and does not induce dysplastic features at the epithelium or inflammation at the connective tissue. The ion promotes histologic alterations on mucosa that need to be investigated in further studies. 相似文献
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The aim of this study was to analyse the immunohistochemical differentiation profile of the stratified squamous epithelium of the adult human lip. Full-thickness lower lips taken from 31 cadavers were analysed. Sections were stained with haematoxylin and eosin, periodic acid-Schiff (PAS), cytokeratins (CK), loricrin, involucrin, profilaggrin and filaggrin. The stratified squamous epithelium covering the lip could be divided into: (i) appendage-bearing, orthokeratinised epidermis; (ii) orthokeratinised vermilion which had a more prominent rete pattern than the epidermis; (iii) parakeratinised, PAS-positive intermediate zone; and (iv) non- or parakeratinised labial mucosal epithelium. Epithelial thickness increased gradually from the skin to the mucosal aspect. The CK pattern changed across the intermediate zone, with gradual loss of CK 1 and 10 from the skin, and CK 4, 13 and 19 from the mucosal, aspect. CK 5 and 14 were consistently expressed basally, and variably expressed suprabasally. Apart from labelling Merkel cells, CK 8, 18 and 20 were negative. Involucrin, which was present at all sites, was restricted to the stratum granulosum in skin, but extended into the stratum spinosum, and gradually into parabasal keratinocytes, across the vermilion and mucosa. Loricrin, profilaggrin and filaggrin were present in the stratum granulosum of orthokeratinised sites, but expression was abruptly lost at the junction between the vermilion and the intermediate zone. In conclusion, the phenotype of the stratified squamous epithelium covering the lip changes at, or across, the intermediate zone of the adult vermilion. It is possible that changes in the composition of the stratified squamous epithelium affect the colour of the vermilion. 相似文献
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Keisam Anupama Devi Ningthoujam Damayanti Moirangthem Matum 《Journal of the Anatomical Society of India》2018,67(2):166-170
Introduction
The histological changes during the development of the human uterus throughout the fetal period exhibit varying cellular patterns in the lining epithelium. The present study documents these progressive changes during fetal uterine maturation.Methods
70 fetal uteri whose age varies from 14th to 40th gestational weeks without any external anomalies were studied.Results
At 14 weeks, the uterine lining epithelium is predominantly pseudostratified columnar, the nuclei being arranged at varying levels. However, the lower part of cervix shows epithelium comprising of a mosaic of flat or slightly raised polygonal cells which gradually changes to stratified squamous epithelium with advancing gestation. From 32 weeks onwards, the pseudostratification of uterine epithelium changes to simple columnar epithelium progressively. At 14 weeks, two distinct layers of mesenchymal cells are apparent, elongated cells in abundance at the subserosal layer and sparsely arranged rounded cells towards the lumen. Endometrial glands appear by the 17th week.Discussion
Except for the lower part of cervix, pseudostratified columnar epithelium lines the fetal uterus. As gestation progresses, pseudostratification gradually changes to simple columnar epithelium. The palmate folds of the epithelium appear by 17 weeks in cervical canal. The smooth muscle bundle appears by 24 weeks of gestation. Undifferentiated mesenchymal cells around paramesonephric duct develop into both smooth muscles and endometrial cells. 相似文献8.
目的 应用白细胞介素6(IL-6)作用于人胰腺癌细胞株SW1990、Capan-2和沉默STAT3基因的SW1990细胞,观察细胞上皮间质转换相关基因的变化并探讨其机制.方法 使用IL-6作用人胰腺癌细胞株SW1990、Capan-2和沉默STAT3基因的SW1990细胞.MTT法检测细胞增殖.荧光定量PCR、Real-time PCR、Western blot检测STAT3、p-STAT3、Snail、Twist和E-cadherin基因mRNA和蛋白表达.体外侵袭实验检测细胞的侵袭能力.结果 100μg/L IL-6作用人胰腺癌细胞株后,细胞增殖能力增强(P<0.05).Western blot显示P-STAT3的表达增加;荧光定量PCR、Real-time PCR、Western blot显示Snail mRNA和蛋白表达明显升高(P<0.05);E-cadherinmRNA和蛋白表达明显降低(P<0.05);细胞侵袭能力增强.而IL-6作用沉默STAT3基因的SW1990细胞,Snail和E-cadherin mRNA和蛋白表达均无明显改变.结论 IL-6可能通过激活STAT3信号转导通路,上调Snail和下调E-cadherin基因表达,促进胰腺癌细胞上皮间质转换,进而增强侵袭能力. 相似文献
9.
《Biomaterials》2015
Surgical management of long-gap esophageal defects with autologous gastrointestinal tissues is frequently associated with adverse complications including organ dysmotility, dysphagia, and donor site morbidity. In order to develop alternative graft options, bi-layer silk fibroin (SF) scaffolds were investigated for their potential to support functional tissue regeneration in a rodent model of esophageal repair. Onlay esophagoplasty was performed with SF matrices (N = 40) in adult rats for up to 2 m of implantation. Parallel groups consisted of animals implanted with small intestinal submucosa (SIS) scaffolds (N = 22) or sham controls receiving esophagotomy alone (N = 20). Sham controls exhibited a 100% survival rate while rats implanted with SF and SIS scaffolds displayed respective survival rates of 93% and 91% prior to scheduled euthanasia. Animals in each experimental group were capable of solid food consumption following a 3 d post-op liquid diet and demonstrated similar degrees of weight gain throughout the study period. End-point μ-computed tomography at 2 m post-op revealed no evidence of contrast extravasation, fistulas, strictures, or diverticula in any of the implant groups. Ex vivo tissue bath studies demonstrated that reconstructed esophageal conduits supported by both SF and SIS scaffolds displayed contractile responses to carbachol, KCl and electrical field stimulation while isoproterenol produced tissue relaxation. Histological (Masson's trichrome and hematoxylin and eosin) and immunohistochemical (IHC) evaluations demonstrated both implant groups produced de novo formation of skeletal and smooth muscle bundles positive for contractile protein expression [fast myosin heavy chain (MY32) and α-smooth muscle actin (α-SMA)] within the graft site. However, SF matrices promoted a significant 4-fold increase in MY32+ skeletal muscle and a 2-fold gain in α-SMA+ smooth muscle in comparison to the SIS cohort as determined by histomorphometric analyses. A stratified squamous, keratinized epithelium expressing cytokeratin 5 and involucrin proteins was also present at 2 m post-op in all experimental groups. De novo innervation and vascularization were evident in all regenerated tissues indicated by the presence of synaptophysin (SYP38)+ boutons and vessels lined with CD31 expressing endothelial cells. In respect to SIS, the SF group supported a significant 4-fold increase in the density of SYP38+ boutons within the implant region. Evaluation of host tissue responses revealed that SIS matrices elicited chronic inflammatory reactions and severe fibrosis throughout the neotissues, in contrast to SF scaffolds. The results of this study demonstrate that bi-layer SF scaffolds represent promising biomaterials for onlay esophagoplasty, capable of producing superior regenerative outcomes in comparison to conventional SIS scaffolds. 相似文献
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