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We present the synthesis of amorphous, mesoporous, colloidal magnesium phosphate-citrate nanoparticles (MPCs) from biogenic precursors, resulting in a biocompatible and biodegradable nanocarrier that amplifies the action of the anticancer drug methotrexate (MTX). Synthesis conditions were gradually tuned to investigate the influence of the chelating agent citric acid on the colloidal stability and the mesoporosity of the obtained nanoparticles. With optimized synthesis conditions, a large BET surface area of 560 m 2 /g was achieved. We demonstrate the potential of these biocompatible and biodegradable mesoporous MPCs as a drug delivery system. Lipid-coated MPCs were used to load the fluorescent dye calcein and the chemotherapeutic agent MTX into the mesopores. In vitro experiments show very low premature release of the cargo but efficient stimuli-responsive release in an environment of pH 5.5, in which MPCs degrade. Lipid-coated MPCs are taken up by cancer cells and are nontoxic up to concentrations of 100 μg/mL. When loaded with MTX serving as a representative model drug for in vitro studies, MPCs induced efficient cell death with an IC 50 value of 1.1 μg/mL. Compared to free MTX, its delivery with MPCs enhances its efficiency by an order of magnitude. In summary, we have developed a biodegradable nanomaterial synthesized from biocompatible precursors that are neither toxic by themselves nor in the form of nanoparticles. With these features, MPCs may be applied as drug delivery systems and have the potential to reduce the side effects of current chemotherapies.

The reaction of fumaryl fluoride with the superacidic solutions XF/MF 5 (X=H, D; M=As, Sb) results in the formation of the monoprotonated and diprotonated species, dependent on the stoichiometric ratio of the Lewis acid to fumaryl fluoride. The salts [C 4 H 3 F 2 O 2 ] + [MF 6 ] - (M=As, Sb) and [C 4 H 2 X 2 F 2 O 2 ] 2+ ([MF 6 ] - ) 2 (X=H, D; M=As, Sb) are the first examples with a protonated acyl fluoride moiety. They were characterized by low-temperature vibrational spectroscopy. Low-temperature NMR spectroscopy and single-crystal X-ray structure analyses were carried out for [C 4 H 3 F 2 O 2 ] + [SbF 6 ] - as well as for [C 4 H 4 F 2 O 2 ] 2+ ([MF 6 ] - ) 2 (M=As, Sb). The experimental results are discussed together with quantum chemical calculations of the cations [C 4 H 4 F 2 O 2  ⋅ 2 HF] 2+ and [C 4 H 3 F 2 O 2  ⋅ HF] + at the B3LYP/aug-cc-pVTZ level of theory. In addition, electrostatic potential (ESP) maps combined with natural population analysis (NPA) charges were calculated in order to investigate the electron distribution and the charge-related properties of the diprotonated species. The C-F bond lengths in the protonated dication are considerably reduced on account of the +R effect., (© 2022 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

This study shows that the anomeric effect (negative hyperconjugation) that arises in sulfamide, as a result of the relatively short S-N bonds, can be tuned by the utilization of superacidic media. Sulfamide was reacted in binary superacidic systems XF/MF 5 (M=As, Sb; X=H, D) and HF/BF 3 . The colorless salts formed, [X 2 NSO 2 NX 3 ] + [MF 6 ] - and [H 2 NSO 2 NH 3 ] + [BF 4 ] - were characterized by low-temperature vibrational spectroscopy. In the case of [H 2 NSO 2 NH 3 ] + [BF 4 ] - , a single crystal X-ray diffraction study was performed. The salt crystallizes in the monoclinic space group P2 1 /c with four formula units per unit cell. An exclusive N,N'-diprotonation was observed in the superacidic system HF/SbF 5 when using several equivalents of the Lewis acid. Low-temperature vibrational spectra as well as a single-crystal X-ray structure of [H 3 NSO 2 NH 3 ] 2+ 2 [SbF 6 ] - ⋅2 HF are reported. The salt crystallizes in the orthorhombic space group Pna2 1 with four formula units per unit cell. Upon mono- or diprotonation of sulfamide, remarkable structural changes of the sulfur-nitrogen bond lengths were observed. Herein, these changes are discussed together with quantum chemical calculations., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Purpose: To quantify and compare the in vitro adherence of Staphylococcus epidermidis and Pseudomonas alcaligenes to different intraocular lenses (IOLs)., Methods: Fourteen intraocular lenses were used in the experiment. Four of polymethylmethacrylate (PMMA), four of silicone, four of hydrogel and two of acrylic. Eight intraocular lenses were placed in eight test tubes containing 4 ml of Pseudomonas alcaligenes suspension, and six intraocular lenses were placed in six test tubes containing 4 ml of Staphylococcus epidermidis suspension. The bacterial suspension used for adherence tests was 10(8) colony-forming units per milliliter (CFU/mL) which corresponds to 0.5 in the scale of McFarland. The lenses were incubated at 37 degrees for two hours. After this, intraocular lenses were removed from the test tubes and dried twice with the use of distilled and sterile water. The material was spread on blood-agar for cultivation at 35-37 degrees C and was evaluated every 24 hours up to 72 hours. In the samples where there was bacterial growth, the colonies were counted using the conventional laboratory methods. All assays were performed in duplicate., Results: Adherence of Staphylococcus epidermidis to PMMA intraocular lenses was lower than to hydrogel and silicone intraocular lenses. Adherence of Pseudomonas alcaligenes to hydrogel intraocular lenses was lower than to PMMA, acrylic and silicone intraocular lenses., Conclusions: Results suggest that in vitro adherence of Staphylococcus epidermidis and Pseudomonas alcaligenes to intraocular lenses is influenced by type of material of the lens and by microorganism species. Bacterial adherence may play a role in the pathogenesis of some forms of endophthalmitis after cataract surgery. More in vitro and clinical studies are necessary to elucidate the mechanisms by which Staphylococcus epidermidis and Pseudomonas alcaligenes cause endophthalmitis.

Purpose: To evaluate the efficacy of the laser in situ keratomileusis (LASIK) technique in the reduction of anisometropy in adults, for whom conventional treatment was not successful., Methods: A sequence of cases of three eyes of three adult patients, two females and one male, age ranging from 28 and 49 years (average 38.3 years), who underwent LASIK. Two patients were followed up for eighteen months and one for six months., Results: Comparing the corrected visual acuity before surgery with the non-corrected visual acuity after surgery, one eye gained two lines of vision, one eye remained the same and one eye lost one line of vision. All eyes remained without spheric refraction, and astigmatism did not exceed -0.75 D after surgery. There has been an improvement in the symptoms of asthenopia in the three patients., Conclusion: The LASIK technique proved to be efficient in the correction of anisometropy in adults, improving visual accuity and asthenopia complaints, and leading to a similar refraction in both eyes.

Corticosteroids can increase intraocular pressure when administered topically, systemically and even when inhaled. They are routinely used after refractive surgeries to lower or prevent an inflammatory action. In this case history, we present a 36-year-old patient who had a total myopic regression two weeks after LASIK for low myopia, caused by steroid-induced ocular hypertension. The purpose of this report is to describe how the case was managed, the diagnostic hypothesis, and to stress the importance of intraocular pressure measurement after LASIK.

Presence of fungus in the conjunctiva is a constant threat to the eyes, because these microorganisms, defined as opportunistic, may provoke severe ocular infections, in situations as low organic resistance, use of immunosuppressants, antibiotics and epithelial alteration. Our goal here is to report a case of ocular aspergillosis in an immunosuppressed patient where paroxysmal nocturnal hemoglobinuria was diagnosed. A 51-year-old immunosuppressed, thrombocytopenic patient was hospitalized with a diagnosis of paroxysmal nocturnal hemoglobinuria. On examination, she had a visual acuity of 20/40 in the right eye (RE) and light perception in the left (LE). She presented hyposphagma, bilateral conjunctival edema on biomicroscopy and had some multiple and circumscribed conjunctival abscesses in both eyes; clear cornea in both eyes. Fundoscopy of the RE did show any particularity, in the LE there was a smear hemorrhage. Computed tomograph showed a fat periocular infiltration. Magnetic resonance lead to the same finding, compatible with orbital cellulitis. Hemoculture showed Aspergillus growth and direct smears of conjunctival material was negative. There was great improvement while treating her with amphotericin B, but there was complete remission after using 5% natamicyn eye drops. Orbital infections caused by Aspergillus are uncommon, usually appearing in immunosuppressed patients. Frequently they progress insidiously, and can be confounded with other orbital processes. Immunological impairment can inhibit the expression of local and systemic symptoms, resulting in diagnostic confusion. The diagnosis is established by laboratory tests, but culture can be negative in spite of the classical presentation, making the beginning of treatment difficult. In these cases management starts according to the symptoms.