[Sleep apnea and ocular diseases]

Sleep apnea presents as recurrent respiratory arrests or shallow breathing during sleep, resulting in decreased oxygen saturation and sleep disruption. Among its various types, obstructive sleep apnea is the most common. Over the past few decades, the prevalence of sleep apnea has been on the rise, drawing increasing attention, particularly with the growing obesity and aging population. Prolonged exposure to a hypoxic environment due to sleep apnea not only damages multiple systems throughout the body but may also pose a threat to vision. Examining the relationship between sleep apnea and ocular diseases, along with exploring its pathogenesis, has become a prominent research topic in recent years. This article provides a comprehensive review of the existing literature concerning the correlation between sleep apnea and ocular diseases such as glaucoma, optic nerve diseases, retinal and choroidal diseases, and anterior eye segment diseases. In clinical practice, prioritizing early screening and treatment for sleep apnea is crucial to prevent the worsening of associated ophthalmic conditions.

New ursolic acid derivatives bearing 1,2,3-triazole moieties: design, synthesis and anti-inflammatory activity in vitro and in vivo

In order to discover novel anti-inflammatory agents, three series of compounds obtained by appending 1,2,3-triazole moieties on ursolic acid were designed and synthesized. All compounds have been screened for their anti-inflammatory activity by using an ear edema model. The potent anti-inflammatory compound was subjected to in vitro cyclooxygenase COX-1/COX-2 inhibition assays. In general, the derivatives were found to be potent anti-inflammatory activity. Especially, the compound 11b exhibited the strongest activity of all of the compounds prepared, with 82.81% inhibition after intraperitoneal administration, which was better than celecoxib as a positive control. Molecular docking results unclose the rationale for the interaction of the compound 11b with COX-2 enzyme. Further studies revealed that compound 11b exhibited effective COX-2 inhibitory activity, with half-maximal inhibitor concentration (IC50) value of 1.16 µM and selectivity index (SI = 64.66) value close to that of celecoxib (IC50 = 0.93 µM, SI = 65.47). Taken together, these results could suggest a promising chemotype for development of new COX-2-targeting anti-inflammatory agent.

Synthesis and evaluation of ursolic acid-based 1,2,4-triazolo[1,5-a]pyrimidines derivatives as anti-inflammatory agents

Here, two series of novel ursolic acid-based 1,2,4-triazolo[1,5-a]pyrimidines derivatives were synthesized and screened for their anti-inflammatory activity by evaluating their inhibition effect of using LPS-induced inflammatory response in RAW 264.7 macrophages in vitro; the effects of different concentrations of the compounds on the secretion of nitric oxide (NO) and inflammatory cytokines including TNF-α and IL-6 were evaluated. Their toxicity was also assessed in vitro. Results showed that the most prominent compound 3 could significantly decrease production of the above inflammatory factors. Docking study was performed for the representative compounds 3, UA, and Celecoxib to explain their interaction with cyclooxygenase-2 (COX-2) receptor active site. In vitro enzyme study implied that compound 3 exerted its anti-inflammatory activity through COX-2 inhibition.

Synthesis, biological evaluation of benzothiazole derivatives bearing a 1,3,4-oxadiazole moiety as potential anti-oxidant and anti-inflammatory agents

Twenty benzothiazole derivatives bearing a 1,3,4-oxadiazole moiety were synthesized and evaluated for their anti-oxidant and anti-inflammatory activities. Among these compounds, 8h and 8l were appeared to have high radical scavenging efficacies as 0.05 ± 0.02 and 0.07 ± 0.03 mmol/L of IC₅₀ values in ABTS⁺ bioassay, respectively. In anti-inflammatory tests, compound 8h displayed good activity with 57.35% inhibition after intraperitoneal administration, which was more potent than the reference drug (indomethacin). Molecular modeling studies were performed to investigate the binding mode of the representative compound 8h into COX-2 enzyme. In vitro enzyme study implied that compound 8h exerted its anti-inflammatory activity through COX-2 inhibition.

Design, synthesis and evaluation of dihydrotriazine derivatives-bearing 5-aryloxypyrazole moieties as antibacterial agents

In the present investigation, a series of dihydrotriazine derivatives-bearing 5-aryloxypyrazole moieties were synthesized and their structures were confirmed by different spectral tools. The biological evaluation in vitro revealed that some of the target compounds exerted good antibacterial and antifungal activity in comparison with the reference drugs. Among these novel hybrids, compound 10d showed the most potent activity with minimum inhibitory concentration values (MIC) of 0.5 µg/mL against S. aureus 4220, MRSA 3506 and E. coli 1924 strain. The cytotoxic activity of the compounds 6d, 6m, 10d and 10g was assessed in MCF-7 and HeLa cells. Growth kinetics study showed significant inhibition of bacterial growth when treated with different conc. of 10d. In vitro enzyme study implied that compound 10d exerted its antibacterial activity through DHFR inhibition. Moreover, significant inhibition of biofilm formation was observed in bacterial cells treated with MIC conc. of 10d as visualized by SEM micrographs. Twenty-nine target compounds were designed, synthesized and evaluated in terms of their antibacterial and antifungal activities.

Synthesis and molecular docking studies of novel pyrimidine derivatives as potential antibacterial agents

The present work describes the in vitro antibacterial evaluation of some new pyrimidine derivatives. Twenty-two target compounds were designed, synthesized and preliminarily explored for their antimicrobial activities. The antimicrobial assay revealed that some target compounds exhibited significantly inhibitory efficiencies toward bacteria and fungal including drug-resistant pathogens. Compound 7c presented the most potent inhibitory activities against Gram-positive bacteria (e.g., Staphylococcus aureus 4220), Gram-negative bacteria (e.g., Escherichia coli 1924) and the fungus Candida albicans 7535, with an MIC of 2.4 μmol/L. Compound 7c was also the most potent, with MICs of 2.4 or 4.8 μmol/L against four multidrug-resistant, Gram-positive bacterial strains. The toxicity evaluation of the compounds 7c, 10a, 19d and 26b was assessed in human normal liver cells (L02 cells). Molecular docking simulation and analysis suggested that compound 7c has a good interaction with the active cavities of dihydrofolate reductase (DHFR). In vitro enzyme study implied that compound 7c also displayed DHFR inhibition.

Whispering-gallery-mode excitation in a microsphere by use of an etched cavity on a multimode fiber end

In this Letter, we demonstrate a whispering-gallery-mode (WGM) microsphere resonator. The device is fabricated by fusion splicing a section of no-core fiber with multimode fiber (MMF) and single-mode fiber at its two ends. The open end of the MMF is etched to create an arc-shaped cavity, with a microsphere glued at its bottom. When the arc of the cavity bottom and microsphere surface are tangent, part of the incident light is coupled into the microsphere and travels exactly one circle before being directed back to the MMF core along the tangent line and exciting the WGM. The device has a Q-factor of 1.21×10⁴, and is robust in structure and low in cost.

[Clinical characteristics and treatment of congenital fibrovascular pupillary membranes]

Objective: To investigate the clinical characteristics, surgical approaches and postoperative effects associated with congenital fibrovascular pupillary membranes. Methods: A retrospective study design was used. Thirteen children (13 eyes) with congenital fibrovascular pupillary membranes, treated in Beijing Children's Hospital from January 2014 to December 2017 were included. The morphology of the membrane and the anterior chamber was evaluated using a digital wide-area fundus imaging system. The ophthalmic signs, examination results, operation methods, intraocular pressure and ocular position were analyzed. Results: There were 13 children (13 eyes) were enrolled, including 9 males and 4 females. The age at surgery ranged from 2.0 months to 34.5 months, with an median of 5.1 months. According to the degree of obstruction of the pupil and the intraocular pressure, the eyes were divided into three groups. In the 5 eyes of group A, the pupil membrane did not completely cover the pupil, and the depth of the anterior chamber was normal. Among them, 4 eyes had normal intraocular pressure (9-12 mmHg) (1 mmHg=0.133kPa), and 1 eye had elevated intraocular pressure (18 mmHg). In the 5 eyes of group B, the pupillary membrane completely covered the pupil into a pinhole, the anterior chamber was normal or slightly shallow, and the intraocular pressure was normal (6-16 mmHg). In the 3 eyes of group C, the pupillary membrane completely covered the pupil, the anterior chamber was shallow or disappeared, and the intraocular pressure was high (24-45 mmHg). Membranectomy and pupilloplasty were performed in group A, and trabeculectomy was combined when there was glaucoma; postoperative intraocular pressure was normal (4-10 mmHg). Membranectomy, pupilloplasty and iridectomy were performed in group B; postoperative intraocular pressure was normal (7-13 mmHg). Membranectomy, pupilloplasty, iridectomy and goniosychialysis were performed in group C; after surgery, intraocular pressure was normal in 2 eyes (10 mmHg and 13 mmHg) and 25 mmHg in 1 eye. All eyes were orthophoric before and after operation in group A. In group B, 1 eye was esotropic, 2 eyes were exotropic (worse after surgery in 1 eye), and 2 eyes were orthophoric before surgery. In group C, one eye was esotropic, one eye was exotropic, and one eye was orthophoric before surgery, and all eyes were exotropic after operation. Conclusions: Congenital fibrovascular pupillary membranes are unilaterally a continuation of the iris covering the pupil at different degrees, with or without glaucoma. Surgical treatment should be performed promptly when there is obscuring of the visual axis or incorporating of glaucoma. The main surgical procedures are membranectomy and pupilloplasty and iridectomy. Postoperative intraocular pressure can be well controlled, and strabismus has no improvement. (Chin J Ophthalmol, 2018, 54:849-854).

Effects of infection by HIV-1, cytomegalovirus, and human measles virus on cultured human thymic epithelial cells

A tissue culture system for the growth of human fetal and infantile thymic epithelial (TE) cells has been established and characterized. We have investigated the effects of infection of these cells by human cytomegalovirus (CMV), measles virus, and human immunodeficiency virus type-1 (HIV-1). In the case of CMV, morphological changes were apparent by 2-4 days after viral inoculation of infantile TE cells. CMV-related antigens were detected by immunofluorescence after 12 days, and progeny infectious CMV was recovered from culture media after 18 days. Following infection by measles virus, distinctive, multinucleated giant TE cells appeared in both cultures of fetal and infantile TE cells. Measles virus-inoculated TE cells displayed an altered phenotype, as revealed by reaction with monoclonal antibodies with specificity for a variety of TE markers. Finally, infection of TE cells by HIV-1 resulted in cellular disarrangement, increased numbers of Hassall's corpuscles, and multinucleated giant cells. An increase in the number of cells reactive with monoclonal antibodies, specific for Hassall's corpuscles, was observed in the case of cells infected by either measles virus or HIV-1. These findings suggest that a variety of different viruses can successfully infect thymic epithelial tissue. Because of the important role of the thymus in development of the immune system, it is reasonable to conclude that viral infection of thymic tissue might play an important role in virus-mediated suppression of immune responsiveness.

Infection of cultured human thymic epithelial cells by human immunodeficiency virus

We have succeeded in growing the HTLV-IIIB strain of human immunodeficiency virus type 1 (HIV-1) in cultured human thymic epithelial (TE) cells. Expression of the HIV-1 proteins p17 and p24 was detected by immunofluorescence and reached a peak at 3 days after infection. Antigen capture and reverse transcriptase assays were used to detect HIV-1 in culture fluids, with positive results also being realized. The infection was cytolytic; cellular disarrangement, increased numbers of Hassall's corpuscles, and giant cells first appeared in monolayers of TE cells at 2 days after inoculation. By 4 days these changes were increased, and by 7 days, retraction and involution of TE cells were evident. The infection of TE cells by HIV-1 was blocked by preincubation with monoclonal OKT4A antibodies directed against CD4 target molecules.