Mechanisms in the Synthesis of S-Alcohols with 1,4-NADH Biomimetic Co-factor N-Benzyl-1,4-dihydronicotinamide using Horse Liver Alcohol Dehydrogenase: A Hybrid Computational Study.

The enantioselective reduction of prochiral ketones catalyzed by horse liver alcohol dehydrogenase (HLADH), was investigated via a hybrid computational approach, for molecular reactions involved in chiral synthesis of S-alcohols, when the natural co-factor, 1,4-dihyronicotinamide adenine dinucleotide, 1,4-NADH, was replaced with biomimetic co-factor, N-benzyl-1,4-dihydronicotinamide, 1. We surmised that different hydride and proton transfer mechanisms were involved using co-factor, 1. An alternative mechanism, where the hydride transfer step occurred, via an η-keto-S-η-5,6-1,4-dihydronicotinamide-Zn(II) complex, was previously investigated with a model of the HLADH-Zn(II) catalytic site (J.

MANAGEMENT OF LARGE FULL-THICKNESS MACULAR HOLES: Long-Term Outcomes of Internal Limiting Membrane Flaps and Internal Limiting Membrane Peels.

Background/purpose: To determine and compare the efficacy of a surgical internal limiting membrane (ILM) flap technique with the traditional ILM peel on long-term visual and anatomical outcomes for large (>400 µm) full-thickness macular holes.

Methods: From October 2016 to July 2022, patients undergoing initial full-thickness macular hole repair with the ILM flap or ILM peel technique were reviewed. Final outcomes were recorded and based on size in microns: 401 to 800, 801 to 1,200, and >1,200.

Rebuttal to the article Pathological crystal structures.

A section in the Acta Crystallographica Section C article by Raymond & Girolami [Acta Cryst. (2023), C79, 445-455] stated that the product of the reaction of [(Cp*Rh)(μ-OH)] (Cp* is 1,2,3,4,5-pentamethylcyclopentadiene) with 1-methylthymine (1-MT) at pH 10 and 60 °C, to synthesize the anionic component [Rh(η-N-1-MT)], was not an Rh complex, but rather an Ag complex, due to the use of silver triflate (AgOTf) to remove Cl from [Cp*RhCl] to synthesize [Cp*Rh(HO)](OTf), a water-soluble crystalline complex. We will clearly show that this premise, as stated, is invalid, while the authors have simply avoided several important facts, including that Cp*OH, a reductive elimination product, at pH 10 and 60 °C, was unequivocally identified, thus leading to the Rh anionic component [Rh(η-N-1-MT)].

Demographic and Socioeconomic Factors in Prospective Retina-Focused Clinical Trial Screening and Enrollment.

Historically marginalized populations are disproportionately affected by many diseases that commonly affect the retina, yet they have been traditionally underrepresented in prospective clinical trials. This study explores whether this disparity affects the clinical trial enrollment process in the retina field and aims to inform future trial recruitment and enrollment. Age, gender, race, ethnicity, preferred language, insurance status, social security number (SSN) status, and median household income (estimated using street address and zip code) for patients referred to at least one prospective, retina-focused clinical trial at a large, urban, retina-based practice were retrospectively extracted using electronic medical records.

Loss to Follow-Up Among Patients With Proliferative Diabetic Retinopathy in Clinical Practice.

Purpose: To determine the proportion of patients with proliferative diabetic retinopathy (PDR) who were counted as loss to follow-up (LTFU) patients and to investigate predictive factors.

Design: Retrospective cohort study.

Methods: Information was collected for 4,423 patients with PDR between April 30, 2012, and April 30, 2017.

ENDOPHTHALMITIS AFTER INTRAVITREAL INJECTION: Role of Prophylactic Topical Ophthalmic Antibiotics.

Purpose: To determine the rate of postintravitreal injection endophthalmitis and to assess microbiological features and outcomes with and without the use of peri-intravitreal injection topical ophthalmic antibiotics.

Methods: Consecutive series of endophthalmitis cases retrospectively identified after intravitreal injection at a multicenter, retina-only referral practice (Retina Consultants of Houston) from January 1, 2011 to December 31, 2014. Prophylactic peri-intravitreal injection topical antibiotics were routinely used during the initial 12-month period (January 1, 2011-December 31, 2011) and not used in the final 24-month period (January 1, 2013-December 31, 2014).

CHOROIDAL NEOVASCULARIZATION SECONDARY TO ALEXANDRITE LASER EXPOSURE.

Purpose: To report macular photic trauma after accidental occupational exposure to a 750-nm Alexandrite laser and management of secondary choroidal neovascularization.

Methods: Institutional review board-approved retrospective case report.

Results: A 30-year-old woman presented with immediate vision loss in her left eye after direct inadvertent exposure to a single discharge from an occupational 750-nm Alexandrite laser used for laser hair removal.

The chemoselective reactions of tyrosine-containing G-protein-coupled receptor peptides with [Cp*Rh(H2O)3](OTf)2, including 2D NMR structures and the biological consequences.

The bioconjugation of organometallic complexes with peptides has proven to be a novel approach for drug discovery. We report the facile and chemoselective reaction of tyrosine-containing G-protein-coupled receptor (GPCR) peptides with [Cp*Rh(H(2)O)(3)](OTf)(2), in water, at room temperature, and at pH 5-6. We have focused on three important GPCR peptides; namely, [Tyr(1)]-leu-enkephalin, [Tyr(4)]-neurotensin(8-13), and [Tyr(3)]-octreotide, each of which has a different position for the tyrosine residue, together with competing functionalities.

Fluoroponytailed crown ethers and quaternary ammonium salts as solid-liquid phase transfer catalysts in organic synthesis.

Fluorous derivatives of dibenzo-18-crown-6 ether were prepared, and then successfully applied in representative solid-liquid phase transfer catalysis reactions, which were performed in standard organic solvents, such as chlorobenzene and toluene, as well as in fluorous solvents, such as perfluoro-1,3-dimethylcyclohexane. It was clearly shown that properly designed fluoroponytailed crown ethers could promote the disintegration of the crystal lattice of alkali salts, and transfer anions from the solid surface into an apolar, non-coordinating perfluorocarbon phase, for phase transfer catalysis reactions in organic synthesis. Furthermore, 3,5-bis(perfluorooctyl)benzyl bromide and triethylamine were reacted under mild conditions to provide an analogue of the versatile phase transfer catalyst, benzyltriethylammonium chloride, containing two fluoroponytails.

Use of nepafenac (Nevanac) in combination with intravitreal anti-VEGF agents in the treatment of recalcitrant exudative macular degeneration requiring monthly injections.

Purpose: The purpose of this study is to determine the efficacy of combining topical nepafenac with monthly intravitreal injections of ranibizumab or bevacizumab in the treatment of recalcitrant exudative macular degeneration.

Methods: This was a retrospective, consecutive case series of patients with exudative macular degeneration requiring maintenance therapy of antivascular endothelial growth factor ( anti-VEGF) injections at least every 6 weeks, who were started on topical nepafenac. Despite frequent anti-VEGF dosing, all patients included in the study had persistence of any combination of the following: intraretinal cysts, subretinal fluid, and/or pigment epithelial detachment.

Synthetic and mechanistic pathways of cis and trans-hydroxytamoxifen drug derivatives reacting with Cp*Rh complexes that involve η1-N, η2-N,O, η1-O, and η6 bonding modes, via a novel N-π rearrangement; relative binding affinities and computer docking studies of cis and trans-η6-Cp*Rh-hydroxytamoxifen complexes at the estrogen, ERα and ERβ receptors, and growth inhibition to breast cancer cells.

The reactions of the breast cancer drug metabolite derivatives of tamoxifen, cis and trans-hydroxytamoxifen, cis-1 and trans-2, with [Cp*Rh(L)(3)](2+) complexes (L = H(2)O or MeOH), in CH(2)Cl(2) and CH(3)OH solvents, initially provided the kinetic η(1)-N complexes, cis-4 (OTf(-), CH(3)OH) and trans-5 (OTf(-), CH(3)OH), which underwent a novel, regioselective, intramolecular N-π rearrangement to give the cis and trans-η(6)-phenol substituted complexes, cis-6 and trans-7, via η(2)-N,O, η(1)-O, and ether aromatic ring η(6) intermediates. Recent density functional theory (DFT) calculations showed a preferred ground state for η(1)-N; η(2)-N,O; η(1)-O; and the η(6) complexes, including the prominent roles of the triflate anion (OTf(-)), and solvent molecules (CH(2)Cl(2) and CH(3)OH), and provided further steric, electronic, and thermodynamic data on the mechanism of the N-π rearrangement. The η(6) complex, cis-6, was shown to be an antagonist for ERα estrogen receptor binding, in a competition experiment with the female hormone, estradiol; therefore, computer docking studies of this biologically active complex at the estrogen receptors, ERα and ERβ, also provided information on the binding modes and thermodynamic parameters, while bioassay results provided growth inhibition data on both hormone dependent and independent breast cancer cell lines.

Spectral domain optical coherence tomography as an effective screening test for hydroxychloroquine retinopathy (the "flying saucer" sign).

Purpose: While the long-term incidence of hydroxychloroquine (HCQ) retinopathy is low, there remains no definitive clinical screening test to recognize HCQ toxicity before ophthalmoscopic fundus changes or visual symptoms. Patients receiving HCQ were evaluated with spectral domain optical coherence tomography (SD OCT) to assess the feasibility of identifying HCQ retinopathy at an early stage.

Methods: Twenty-five patients referred for the evaluation of hydroxychloroquine toxicity underwent a comprehensive ocular examination, Humphrey visual field (HVF) perimetry, time domain OCT, and SD OCT.

Lucentis using Visudyne study: determining the threshold-dose fluence of verteporfin photodynamic therapy combined with intravitreal ranibizumab for exudative macular degeneration.

Purpose: Combination verteporfin photodynamic therapy (vPDT) and antivascular endothelial growth factor (anti-VEGF) therapy may decrease the need for injections while maintaining visual acuity in exudative age-related macular degeneration. This pilot study was designed to determine the threshold fluence dose of vPDT (the dose required to demonstrate an effect on choroidal perfusion) combined with ranibizumab.

Methods: Seven patients were randomized to sham vPDT (two patients), 20% fluence vPDT (two patients), or 40% fluence vPDT (three patients) in combination with three-monthly intravitreal 0.

A DFT study on the mechanism of a novel, regioselective, intramolecular N-pi rearrangement of cis and trans-eta1-N-Cp*Rh-hydroxytamoxifen complexes to their eta6 derivatives; potential breast cancer pharmaceuticals, and fluorescent probes.

The previously reported reactions of cis and trans-hydroxytamoxifen drug derivatives, 1 and 2, with [Cp*Rh(L)(3)](2+) complexes (L = H(2)O, CH(3)OH), initially provided the kinetically controled eta(1)-N complexes, 4(OTf, CH(3)OH) and 5(OTf, CH(3)OH), which underwent a novel, intramolecular, regioselective N-pi rearrangement to provide the eta(6) complexes, 6 and 7. A dramatic solvent effect was also observed on the rate of this N-pi rearrangement in CH(3)OH or CH(2)Cl(2). Therefore, a DFT study was conducted that provided further mechanistic and thermodynamic data on this N-pi rearrangement.

Selected clinical comparisons of spectral domain and time domain optical coherence tomography.

The authors report four cases where spectral domain optical coherence tomography (SD-OCT) imaged pathology not captured by time domain optical coherence tomography (TD-OCT). These cases include one of angioid streaks, two of juxtafoveal telangiectasia, and one of age-related macular degeneration. In each case, the improved images provided by SD-OCT changed either the management of the patient or the counseling of their disease process.

Studies on the reactivity of organometallic Ru-, Rh- and Os-pta complexes with DNA model compounds.

The reactions of arene-metal complexes (arene=p-cymene, benzene or pentamethylcyclopentadienyl, metal=Ru, Rh or Os), including 1,3,5-triaza-7-phosphatricyclo-[3.3.1.

Long-term stability of circumferential silicone sponge scleral buckling exoplants.

Purpose: The historical extrusion/explantation rate of silicone sponge scleral buckle exoplants is 3.5 to 24.4%.

Fluorocarbon soluble copper(II) carboxylate complexes with nonfluoroponytailed nitrogen ligands as precatalysts for the oxidation of alkenols and alcohols under fluorous biphasic or thermomorphic modes: structural and mechanistic aspects.

This fluorous biphasic catalysis (FBC) contribution was focused on the synthesis and characterization of new fluorous soluble R(f)-Cu(II) carboxylate complexes containing nonfluoroponytailed ligands and defines their role as precatalysts for the FBC oxidation of alkenols and alcohols in the presence of 2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPO)/O(2). In this FBC approach, we have utilized the phase-switching technique of Vincent et al. (J.

Polyfluorinated quaternary ammonium salts of polyoxometalate anions: fluorous biphasic oxidation catalysis with and without fluorous solvents.

[reaction: see text] Polyfluorinated quaternary ammonium cations, [CF(3)(CF(2))(7)(CH(2))(3)](3)CH(3)N(+) (R(F)N(+)), were synthesized and used as countercations for the [WZnM(2)(H(2)O)(2)(ZnW(9)O(34))(2)](12)(-) (M = Mn(II), Zn(II)) polyoxometalate. The (R(F)N(+))(12)[WZnM(2)(H(2)O)(2)(ZnW(9)O(34))(2)] compounds were fluorous biphasic catalysts for alcohol and alkenol oxidation, and alkene epoxidation with aqueous hydrogen peroxide. Reaction protocols with or without a fluorous solvent were tested.

Fluorous biphasic catalysis: synthesis and characterization of copper(I) and copper(II) fluoroponytailed 1,4,7-Rf-TACN and 2,2'-Rf-bipyridine complexes--their catalytic activity in the oxidation of hydrocarbons, olefins, and alcohols, including mechanistic implications.

In this contribution on fluorous biphasic catalysis (FBC), we present the synthesis and characterization of new copper complexes, and define their role, as precatalysts, in the FBC oxidation of hydrocarbons, olefins, and alcohols. Thus the previously reported, but poorly characterized, fluoroponytailed ligand, 2,2'-R(f)-bipyridine (R(f)=-(CH(2))(3)C(8)F(17)) 2, as well as the new Cu(II) fluoroponytailed carboxylate synthon complex [Cu(C(8)F(17)(CH(2))(2)CO(2))(2)] 3, will be addressed. Moreover, the reaction of previously described ligands, 1,4,7-R(f)-TACN 1, or 2,2'-R(f)-bipyridine 2 with 3 afforded new perfluoroheptane-soluble Cu(II) complexes, [Cu(C(8)F(17)(CH(2))(2)CO(2))(2)(R(f)-tacn)] 4 and [Cu(C(8)F(17)(CH(2))(2)CO(2))(2)(R(f)-bpy)] 5, respectively.

A New, Aqueous (1)H NMR Shift Reagent Based on Host-Guest Molecular Recognition Principles for Organic Compound Structural Analysis: Non-covalent pi-pi and Hydrophobic Interactions Using a Supramolecular Host, [CpRh(2'-deoxyadenosine)](3)(OTf)(3).

We have discovered that the supramolecular host [CpRh(2'-deoxyadenosine)](3)(OTf)(3) (1, Cp = eta(5)-C(5)Me(5), OTf = CF(3)SO(3)(-)) has utility as a new, aqueous (1)H NMR shift reagent, via a host-guest molecular recognition process that occurs by non-covalent pi-pi and hydrophobic interactions, with a wide variety of H(2)O-soluble organic substrates. These organic compound guests that we present, to illustrate the utility of host 1 as a novel, aqueous (1)H NMR shift reagent, encompass examples such as aromatic carboxylic acids, phenylacetic acid (G1), 1-naphthoic acid (G2), and 2-naphthoic acid (G3), an aliphatic carboxylic acid, cyclohexylacetic acid (G4), as well as biological compounds, a di- and a tetrapeptide containing terminal L-tryptophan (Trp) or L-phenylalanine (Phe) groups, L-Trp-L-Phe (G5) and L-Trp-L-Met-L-Asp-L-Phe amide (G6) in the pH range 5-10. A discussion of the molecular recognition parameters that effect the (1)H NMR shifts of the organic guests and a comparison with the water-soluble lanthanide shift reagents (LSRs) will be presented to demonstrate the usefulness of this aqueous molecular receptor as an aid for organic compound structural analysis.

Biomimetic Oxidation Studies. 11. Alkane Functionalization in Aqueous Solution Utilizing in Situ Formed [Fe(2)O(eta(1)-H(2)O)(eta(1)-OAc)(TPA)(2)](3+), as an MMO Model Precatalyst, Embedded in Surface-Derivatized Silica and Contained in Micelles.

The biomimetic, methane monooxygenase enzyme (MMO) precatalyst, [Fe(2)O(eta(1)-H(2)O)(eta(1)-OAc)(TPA)(2)](3+) (TPA = tris[(2-pyridyl)methyl]amine), 1, formed in situ at pH 4.2 from [Fe(2)O(&mgr;-OAc)(TPA)(2)](3+), 2, was embedded in an amorphous silicate surface modified by a combination of hydrophilic poly(ethylene oxide) and hydrophobic poly(propylene oxide). The resulting catalytic assembly was found to be a biomimetic model for the MMO active site within a hydrophobic macroenvironment, allowing alkane functionalization with tert-butyl hydroperoxide (TBHP)/O(2) in an aqueous reaction medium (pH 4.

Regioselective Reduction of NAD Models with [Cp*Rh(bpy)H] : Structure-Activity Relationships and Mechanistic Aspects in the Formation of the 1,4-NADH Derivatives.

The hydride transfer mechanism of the NAD model compound 1 to its 1,4-NADH derivative 3 [Eq. (1)] is proposed to be a consequence of the critical role of the carbonyl group of the amide to coordinate to the ring-slipped η - to η -Cp*Rh metal center of the catalyst [Cp*Rh(bpy)H] , prepared in situ from 2, while a steric effect of a substituent in the 3 position, for example, C(O)NEt , was found to totally inhibit this regioselective reduction. bpy=2,2'-bipyridine, Cp*=C Me , OTf=trifluoromethanesulfanate.