Cultured Thymic Epithelium. Its Morphological Characterization and Biological Effect in Vivo in Athymic Nude Rats

Recent studies confirmed that some Hepatozoon-like blood parasites (Apicomplexa) of birds are closely related to the amphibian parasite Lankesterella minima. Little is known about the biology of these pathogens in birds, including their distribution, life cycles, specificity, vectors, and molecular characterization. Using blood samples of 641 birds from 16 species, we (i) determined the prevalence and molecular diversity of Lankesterella parasites in naturally infected birds; (ii) investigated the development of Lankesterella kabeeni in laboratory-reared mosquitoes, Culex pipiens forma molestus and Aedes aegypti; and (iii) tested experimentally the susceptibility of domestic canaries, Serinus canaria, to this parasite. This study combined molecular and morphological diagnostic methods and determined 11% prevalence of Lankesterella parasites in Acrocephalidae birds; 16 Lankesterella lineages with a certain degree of host specificity and two new species (Lankesterella vacuolata n. sp. and Lankesterella macrovacuolata n. sp.) were found and characterized. Lankesterella kabeeni (formerly Hepatozoon kabeeni) was re-described. Serinus canaria were resistant after various experimental exposures. Lankesterella sporozoites rapidly escaped from host cells in vitro. Sporozoites persisted for a long time in infected mosquitoes (up to 42 days post exposure). Our study demonstrated a high diversity of Lankesterella parasites in birds, and showed that several avian Hepatozoon-like parasites, in fact, belong to Lankesterella genus.

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UVA Exposure Combined with Glycation of the Dermis Are Two Catalysts for Skin Aging and Promotes a Favorable Environment to the Appearance of Elastosis

Journal of Aging Research ◽

10.1155/2021/6647773 ◽

2021 ◽

Vol 2021 ◽

pp. 1-13

Author(s):

Hervé Pageon ◽

Hélène Zucchi ◽

Sylvie Ricois ◽

Philippe Bastien ◽

Daniel Asselineau

Keyword(s):

Protein Expression ◽

Biological Effect ◽

Skin Aging ◽

Chronological Aging ◽

Advanced Glycosylation End Products ◽

Uva Irradiation ◽

Inflammatory State ◽

Aged Skin

Skin aging is the result of superimposed intrinsic (individual) and extrinsic (e.g., UV exposure or nutrition) aging. Previous works have reported a relationship between UV irradiation and glycation in the aging process, leading, for example, to modified radical species production and the appearance of AGEs (advanced glycosylation end products) in increasing quantities, particularly glycoxidation products like pentosidine. In addition, the colocalization of AGEs and elastosis has also been observed. We first investigated the combination of the glycation reaction and UVA effects on a reconstructed skin model to explain their cumulative biological effect. We found that UVA exposure combined with glycation had the ability to intensify the response for specific markers: for example, MMP1 or MMP3 mRNA, proteases involved in extracellular matrix degradation, or proinflammatory cytokine, IL1α, protein expression. Moreover, the association of glycation and UVA irradiation is believed to promote an environment that favors the onset of an elastotic-like phenomenon: mRNA coding for elastin, elastase, and tropoelastin expression is increased. Secondly, because the damaging effects of UV radiation in vivo might be more detrimental in aged skin than in young skin due to increased accumulation of pentosidine and the exacerbation of alterations related to chronological aging, we studied the biological effect of soluble pentosidine in fibroblasts grown in monolayers. We found that pentosidine induced upregulation of CXCL2, IL8, and MMP12 mRNA expression (inflammatory and elastotic markers, respectively). Tropoelastin protein expression (elastin precursor) was also increased. In conclusion, fibroblasts in monolayers cultured with soluble pentosidine and tridimensional in vitro skin constructs exposed to the combination of AGEs and UVA promote an inflammatory state and an alteration of the dermal compartment in relation to an elastosis-like environment.

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Non-invasive Clinical Measurement of Ocular Rigidity and Comparison to Biomechanical and Morphological Parameters in Glaucomatous and Healthy Subjects

Frontiers in Medicine ◽

10.3389/fmed.2021.701997 ◽

2021 ◽

Vol 8 ◽

Author(s):

Yanhui Ma ◽

Sayoko E. Moroi ◽

Cynthia J. Roberts

Keyword(s):

Healthy Subjects ◽

High Speed ◽

Morphological Characteristics ◽

Volume Ratio ◽

Pulse Amplitude ◽

Morphological Characterization ◽

Dynamic Contour Tonometry ◽

Stiffness Parameter ◽

Positive Correlation

Purpose: To assess ocular rigidity using dynamic optical coherence tomography (OCT) videos in glaucomatous and healthy subjects, and to evaluate how ocular rigidity correlates with biomechanical and morphological characteristics of the human eye.Methods: Ocular rigidity was calculated using Friedenwald's empirical equation which estimates the change in intraocular pressure (IOP) produced by volumetric changes of the eye due to choroidal pulsations with each heartbeat. High-speed OCT video was utilized to non-invasively measure changes in choroidal volume through time-series analysis. A control-case study design was based on 23 healthy controls and 6 glaucoma cases. Multiple diagnostic modalities were performed during the same visit including Spectralis OCT for nerve head video, Pascal Dynamic Contour Tonometry for IOP and ocular pulse amplitude (OPA) measurement, Corvis ST for measuring dynamic biomechanical response, and Pentacam for morphological characterization.Results: Combining glaucoma and healthy cohorts (n = 29), there were negative correlations between ocular rigidity and axial length (Pearson R = −0.53, p = 0.003), and between ocular rigidity and anterior chamber volume (R = −0.64, p = 0.0002). There was a stronger positive correlation of ocular rigidity and scleral stiffness (i.e., stiffness parameter at the highest concavity [SP-HC]) (R = 0.62, p = 0.0005) compared to ocular rigidity and corneal stiffness (i.e., stiffness parameter at the first applanation [SP-A1]) (R = 0.41, p = 0.033). In addition, there was a positive correlation between ocular rigidity and the static pressure-volume ratio (P/V ratio) (R = 0.72, p < 0.0001).Conclusions: Ocular rigidity was non-invasively assessed using OCT video and OPA in a clinic setting. The significant correlation of ocular rigidity with biomechanical parameters, SP-HC and P/V ratio, demonstrated the validity of the ocular rigidity measurement. Ocular rigidity is driven to a greater extent by scleral stiffness than corneal stiffness. These in vivo methods offer an important approach to investigate the role of ocular biomechanics in glaucoma.

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Synthesis, Characterization and Cytotoxic Activity of N-(5-indanyl(methylene)anthranilic acid(5-indanyl methylene)-hydrazide and Its Pt(II) Complex

Asian Journal of Research in Biochemistry ◽

10.9734/ajrb/2019/v4i330070 ◽

2019 ◽

pp. 1-12

Author(s):

Nasser Mohammed Hosny ◽

Lamiaa A. A. Barakat

Keyword(s):

Cytotoxic Activity ◽

Anthranilic Acid ◽

Platinum Complex ◽

Platinum Complexes ◽

Ehrlich Ascites Carcinoma ◽

Morphological Characterization ◽

Spherical Particles ◽

Spectral Techniques ◽

Average Size

Since the discovery of the platinum based complex, cisplatin, medicinal inorganic chemistry has attracted much more attention and a large number of platinum complexes with promising pharmacological properties have been synthesized. In this work a new platinum complex of N-(5-indanyl(methylene)anthranilic acid(5-indanyl methylene)-hydrazide (HL) has been synthesized and characterized by physical and spectral techniques, as elemental analysis, IR, EI-MS, 1H-NMR, thermal analysis, transmittance electron microscope (TEM) and magnetic moment. The results indicated that the ligand binds to Pt(II) in the enol form. Square-planar stereochemistry was suggested for the Pt(II) complex. The morphological characterization showed nano-sized spherical particles with average size 92 nm of the isolated complex. The synthesized Pt(II) complex exhibited a significant cytotoxic activity against HCT116 and HEPG2. Also in vivo study of the Pt(II) complex showed cytotoxic activity towards Ehrlich ascites carcinoma (EAC).

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