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1.
PurposeTo evaluate in vivo parameters as biomarkers of limbal stem cell function and to establish an objective system that detects and stage limbal stem cell deficiency (LSCD).MethodsA total of 126 patients (172 eyes) with LSCD and 67 normal subjects (99 eyes) were included in this observational cross-sectional comparative study. Slit-lamp biomicroscopy, in vivo laser scanning confocal microscopy (IVCM), and anterior segment optical coherence tomography (AS-OCT) were performed to obtain the following: clinical score, cell morphology score, basal cell density (BCD), central corneal epithelial thickness (CET), limbal epithelial thickness (LET), total corneal nerve fiber length (CNFL), corneal nerve fiber density (CNFD), corneal nerve branch density (CNBD), and tortuosity coefficient. Their potential correlations with the severity of LSCD were investigated, and cutoff values were determined.ResultsAn increase clinical score correlated with a decrease in central cornea BCD, limbal BCD, CET, mean LET, maximum LET, CNFL, CNFD, CNBD, and tortuosity coefficient. Regression analyses showed that central cornea BCD, CET and CNFL were the best parameters to differentiate LSCD from normal eyes (Coef = 3.123, 3.379, and 2.223; all p < 0.05). The rank correlation analysis showed a similar outcome between the clinical scores and the central cornea BCD (ρ = 0.79), CET (ρ = 0.82), and CNFL (ρ = 0.71). A comprehensive LSCD grading formula based on a combination of these parameters was established.ConclusionsA comprehensive staging system combining clinical presentation, central cornea BCD, CET, and CNFL is established to accurately and objectively diagnose LSCD and stage its severity. 相似文献
2.
《Dental materials》2022,38(6):924-934
ObjectivesTo study the oxide layer stability of certified dental implants of system "P", made based on TiO2 alloy with carbon coating. To perform a comparative statistical analysis of the obtained data with the available data for the dental implants of systems "A" and "B".MethodsX-ray microtomography and X-ray fluorescence analysis were used to study soft tissue biopsy specimens. Supernatants were studied by dynamic light scattering and transmission electron microscopy when simulating free emission of nanoscale metal oxide particles from the surface of dental implants as well as when simulating physical loading. A comparative analysis of three parameters of nanoscale particles was performed by statistical data analysis. The surface of the "P" system dental implant with surface treatment was analyzed by scanning electron microscopy.ResultsBoth free emission of nanoscale oxide layer particles and yield of nano- and microscale particles during simulation of physical load were confirmed. Statistically significant differences were noted in a comparative analysis of the size and frequency of occurrence of these particles in the supernatants obtained from the surfaces of three dental implant systems. The elemental composition of the particles and the composition and structure of the "P" system dental implants themselves were analyzed.SignificanceThe developed method of dynamic light scattering can be used to compare the stability of the oxide layer of standardized medical products manufactured on the basis of the TiO2 alloy. 相似文献
3.
目的 研究成型工艺和结构设计对电子束选区熔化技术(SEBM)制备的菱形十二面体Ti6Al4V点阵材料相对密度、形貌和压缩性能的影响。方法 点阵的密度通过测定其尺寸和质量得出,采用电子万能试验机测试点阵结构的压缩性能,采用扫描电子显微镜观察点阵表面形貌。结果 SEBM成形Ti6Al4V支架的相对密度随着熔化功率增加和单胞尺寸减小而增大;以等离子旋转电极雾化技术制备的TC4粉末为原料成型的点阵结构具有优异的塑性,压缩应力—应变曲线平台区域波动小;TC4钛合金菱形十二面体多孔材料的密度与屈服强度和弹性模量的关系满足Gibson-Ashby方程,但指数分别为2.34和2.32。结论 通过调控点阵结构设计和SEBM成型工艺,可控制钛合金的孔隙率和压缩性能,满足骨科植入多孔材料需求。 相似文献
4.
《Clinical Lymphoma, Myeloma & Leukemia》2020,20(11):757-767.e3
BackgroundTreatment of cutaneous T-cell lymphoma (CTCL) with total skin electron beam (TSEB) therapy has been associated with deep responses but short progression-free intervals. Maintenance therapy might prolong the response duration; however, limited data assessing the outcomes with maintenance therapy after TSEB are available. We evaluated the effect of maintenance therapy on the outcomes for patients with CTCL receiving TSEB therapy.Materials and MethodsWe conducted a single-center retrospective analysis of 101 patients with CTCL who had received TSEB therapy from 1998 to 2018 at the Winship Cancer Institute of Emory University and compared the overall survival (OS) and progression-free survival (PFS) for patients had received maintenance therapy, including retinoids, interferon, ultraviolet therapy, nitrogen mustard, and extracorporeal photopheresis compared with those who had not.ResultsWe found that pooled maintenance therapies improved PFS (hazard ratio [HR], 0.60; P = .026) but not OS (median HR, 0.73; P = .264). The median PFS and OS was 7.2 months versus 9.6 months and 2.4 years versus 4.2 years for the no maintenance and maintenance groups, respectively. On exploratory analysis of the individual regimens, ultraviolet therapy was associated with improved OS (HR, 0.21; P = .034) and PFS (HR, 0.26; P = .002) compared with no maintenance.ConclusionAmong the patients with CTCL who had received TSEB therapy, maintenance therapy improved PFS for all patients, and ultraviolet-based maintenance improved both PFS and OS in a subset of patients. 相似文献
5.
6.
Abdol-Mohammad Kajbafzadeh Reza Khorramirouz Seyedeh Maryam Kameli Kiarad Fendereski Seyedeh Sima Daryabari Seyed Mohammad Tavangar Bahram Azizi Garajegayeh 《The Journal of thoracic and cardiovascular surgery》2019,157(4):1494-1502
Background
Various investigations have reported that the internal mammary artery (IMA) is an efficient and functional choice of conduit for vascular graft surgeries, especially for coronary artery bypass grafts; however, the quest to find an ideal vascular substitute remains. We hypothesized that acellular IMA could be an appropriate graft for small-diameter vascular bypasses that could be used in various surgeries including coronary artery bypass grafting.Methods
We decellularized human IMAs and performed histologic evaluations and scanning electron microscopy to confirm the decellularization process and the preservation of the extracellular matrix. Subsequently, we grafted the scaffolds into the superficial femoral arteries of 8 New Zealand rabbits with an end-to-end anastomosis. Computed tomography angiograms were provided at 3, 12, and 36 months postoperatively. Subsequently, the animals were killed, and biopsies were taken for histologic and immunohistochemical assessments.Results
Evaluation of the acellular tissue confirmed the efficacy of the decellularization protocol and the preservation of the extracellular matrix. All 8 animals survived the entire follow-up period. Doppler ultrasonography and computed tomography angiographies verified the conduit's patency. Histologic assessments depicted the recellularization of all 3 layers of the scaffold. Smooth muscle cells were detected in tunica media. Immunohistochemical assessments confirmed these findings.Conclusions
In conclusion, we demonstrated that acellular human IMA could be used as an efficient small-diameter vascular substitute with high patency. These findings could pave the path for future investigations on the clinical application of acellular IMA as a novel vascular graft for small-diameter bypass surgeries. 相似文献7.
Reflectance confocal microscopy may enhance the accuracy of histopathologic diagnosis: A case series
Neda Shahriari Jane M. Grant‐Kels Harold Rabinovitz Margaret Oliviero Alon Scope 《Journal of cutaneous pathology》2019,46(11):830-838
Although histopathology is the time‐honored gold standard diagnostic measure in dermatology, several factors may detract from an accurate microscopic diagnosis. Limiting factors include: human error, suboptimal biopsy‐site selection or biopsy technique, and inherent restrictions of vertical tissue sectioning that lead to incomplete microscopic evaluation of the lesion. Reflectance confocal microscopy (RCM) is a non‐invasive imaging tool that allows for the cellular‐level examination of the lesion, at a horizontal plane, which may complement the subsequent vertical histopathological tissue examination. Herein, we report a case series whereby prebiopsy RCM examination enhanced the accuracy of histopathological diagnosis or allowed for a critical appraisal of initial histopathological misdiagnosis. 相似文献
8.
《Saudi Pharmaceutical Journal》2022,30(6):679-692
Croton stellatopilosus (Plaunoi) leaves accumulate several diterpenes and possess various pharmacological activities. The present study aimed to prepare, characterize and assess the antibacterial activity of inclusion complexes prepared by mixing plaunotol (PL) or plaunoi extract (PE) with cyclodextrins (CD), including α-CD, β-CD, γ-CD, and hydroxypropyl-β-cyclodextrin (HP-β-CD). The inclusion complexes were characterized using SEM, XRD, DSC, and FT-IR and evaluated for aqueous solubility and thermal stability. The PL and PE lyophilized complexes with HP-β-CD were further evaluated for their antibacterial activity against acne-causing bacteria. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of PL, PE, and the inclusion complexes evaluated using the agar dilution method revealed that the MIC and MBC values of the inclusion complexes were lower than those of PL or PE alone. Interestingly, the complexes had a synergistic activity with clindamycin after testing with checkerboard assay. The hydrogel containing the inclusion complex and clindamycin were assessed for antibacterial activity using the agar well diffusion method. The results indicated that the hydrogels showed significant inhibition of bacterial growth. In conclusion, the prepared solid dispersion of PL or PE with HP-β-CD could enhance antibacterial activity by increasing the drug solubility. The hydrogels containing PL or PE complex and clindamycin could be considered as a candidate for the treatment of acne vulgaris. 相似文献
9.
Yan Zhang Xiaoyun Pang Jian Li Jiashu Xu Victor W. Hsu Fei Sun 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(10)
The sorting nexin (SNX) family of proteins deform the membrane to generate transport carriers in endosomal pathways. Here, we elucidate how a prototypic member, SNX1, acts in this process. Performing cryoelectron microscopy, we find that SNX1 assembles into a protein lattice that consists of helical rows of SNX1 dimers wrapped around tubular membranes in a crosslinked fashion. We also visualize the details of this structure, which provides a molecular understanding of how various parts of SNX1 contribute to its ability to deform the membrane. Moreover, we have compared the SNX1 structure with a previously elucidated structure of an endosomal coat complex formed by retromer coupled to a SNX, which reveals how the molecular organization of the SNX in this coat complex is affected by retromer. The comparison also suggests insight into intermediary stages of assembly that results in the formation of the retromer-SNX coat complex on the membrane.Sorting nexins (SNXs) exist as a large family of proteins defined by the presence of a PX (phox homology) domain (1, 2). Members of this family have been found to act as coat proteins in endosomal pathways that include recycling from endosomes to the plasma membrane and retrieval from endosomes to the Golgi complex (3, 4). Defects in these transport processes is associated with various neurologic disorders including Alzheimer’s disease, Parkinson’s disease, and Down’s syndrome (5, 6).Coat proteins assemble into complexes on the membrane to initiate intracellular transport pathways by coupling two main functions: bending the membrane to generate transport carriers and binding to cargoes for their sorting into these carriers (7). Retromer, a trimeric complex consisting of Vps26, Vps29, and Vps35, has been found to couple with different SNXs to form multiple endosomal coat complexes, in which select members of the SNX family act in membrane deformation while retromer acts in cargo recognition (8–17). Recently, a detailed molecular view of this functional cooperation has been achieved by elucidating the structure of a retromer-SNX complex on the membrane (18).Notably, it has been further discovered recently that an endosomal coat complex can be formed with only SNX members. SNX1/2 have been found to heterodimerize with SNX5/6 to form the endosomal SNX–BAR sorting complex for promoting exit 1 (ESCPE-1) complex, in which SNX1/2 are proposed to act in membrane deformation while SNX5/6 act in cargo recognition (19). As such, a key question has become whether SNX that acts in membrane deformation in this type of coat complex would be organized similarly on the membrane, as previously elucidated for SNX in the context of a retromer-SNX complex (18).One of the best characterized mechanisms of membrane deformation involves proteins that possess the BAR (Bin/Amphiphysin/Rvs) domain. This domain has been shown to undergo homodimerization to form a banana-shaped structure, which can impart membrane curvature through a scaffolding mechanism that involves electrostatic interactions between the positive charges lining the concave side of the curved BAR dimer and the negative charges that line the surface of the membrane bilayer. In some cases, the BAR domain can deform the membrane through a second mechanism, which involves the formation of an amphipathic helix that inserts into one leaflet of the membrane bilayer to generate bilayer asymmetry in driving membrane curvature (20, 21).Besides the PX domain, SNX1 also possesses a BAR domain. However, studies have found that its BAR domain is not sufficient in driving membrane deformation. Instead, the PX domain as well as the linker region between the BAR and PX domains are also needed (22, 23). As such, a key goal has been to achieve a better understanding of how the various parts of SNX1 contribute to its ability to deform the membrane.Structural studies, such as those involving crystallography and single-particle electron microscopy (EM), have been advancing a molecular understanding of coat proteins (24), including components of endosomal coats (17, 19, 22, 25–27). Notably, however, these approaches solve protein structures in solution, but the functional form of coat proteins involves their association with the membrane. In this study, we have pursued cryo-EM to reveal how SNX1 is organized on the membrane to explain its ability to deform the membrane. The result advances a molecular understanding of how an endosomal coat that contains only SNXs generates transport carriers. Moreover, by comparing our SNX1 structure to the previously solved retromer-SNX structure (18), we delineate the extent to which the molecular organization of SNX on the membrane is affected by the presence of retromer. This comparison also suggests insight into intermediary stages of coat assembly that form the retromer-SNX complex on the membrane. 相似文献
10.
Xiumei Jiang Xiaowei Zhang Patrick Gray Jiwen Zheng Timothy R. Croley Peter P. Fu 《journal of environmental science and health part c-environmental carcinogenesis & ecotoxicology reviews》2019,37(2):116-131
Gold nanoparticles (Au NPs) hold great promise in food, industrial and biomedical applications due to their unique physicochemical properties. However, influences of the gastrointestinal tract (GIT), a likely route for Au NPs administration, on the physicochemical properties of Au NPs has been rarely evaluated. Here, we investigated the influence of GIT fluids on the physicochemical properties of Au NPs (5, 50, and 100?nm) and their implications on intestinal epithelial permeability in vitro. Au NPs aggregated in fasted gastric fluids and generated hydroxyl radicals in the presence of H2O2. Cell studies showed that GIT fluids incubation of Au NPs affected the cellular uptake of Au NPs but did not induce cytotoxicity or disturb the intestinal epithelial permeability. 相似文献