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1.
Artigo em Inglês | MEDLINE | ID: mdl-38643423

RESUMO

PURPOSE: To assess whether oculoplastic surgeries can be performed without any topical and systemic antibiotics, in a "100% antibiotic free" fashion. METHOD: We conducted a multicenter retrospective study between November 2017 and December 2022. Patients who underwent an oculoplastic procedure were screened. Patients who received preoperative or postoperative systemic antibiotics were excluded. Intraoperative IV antibiotics were allowed. Patients were divided into two groups: those who were treated with local antibiotics ointments (LATB group) and those who were treated without local antibiotics ointments (LATB free group) postoperatively. The primary outcome was the incidence of surgical site infections (SSI). The relationship between the use of local antibiotics and the occurrence of SSI was assessed using Fisher's exact test. The alpha risk was set to 5% and two-tailed tests were used. RESULTS: Among the 947 procedures included, 617 were included in the LATB group and 330 in the LATB free group. 853 and 80 procedures were classified Altemeier class 1 (clean) and class 2 (clean-contaminated) surgeries, respectively. Overall, 310 (32.73%) procedures were performed without any systemic nor topical antibiotics (100% antibiotic free fashion). SSI occured in four (4/617; 0.65%) and five (5/330; 1.52%) procedures in the LATB and LATB free group respectively, without any statistical difference between the groups (p = 0.290). A subgroup analysis was carried out by excluding the procedures performed under prophylactic intraoperative intravenous antibiotics and did not reveal any statistical difference between the two groups (p = 0.144). All SSI patients were treated with systemic antibiotics with favorable outcomes. Postoperative wound dehiscence was the only risk factor associated with postoperative SSI (p = 0.002). CONCLUSION: This study suggests that performing a "100% antibiotic free" oculoplastic surgery without systemic and topical antibiotics is reasonable in Altemeier class 1 and class 2 procedures.

2.
J Org Chem ; 88(3): 1469-1492, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36690446

RESUMO

An improvement in the catalytic enantioselective allylboration of isatins with 2-allyl-1,3,2-dioxaborolane in the presence of chiral BINOL derivatives is reported, offering an efficient one-step access to enantioenriched N-unprotected 3-allyl-3-hydroxy-2-oxindoles. This catalytic process is also effective for the crotylboration reaction with enantiomeric ratios (er) up to 97:3, as well as for the asymmetric synthesis of homopropargylic alcohols via an allenyl addition to indoline-2,3-diones. Origins of the high enantioselectivity in chiral BINOL-catalyzed allylboration of isatins were examined by DFT calculations. A hypothetical scenario suggested a crucial internal hydrogen bonding between the amide group (C═O···H-O) and the ethylene hydroxyl of the transient chiral mixed boronate ester, generating a rigid and stabilized system that favors the addition of the allylboron species to the Re face of the ketone function. The key role of the alcohol additive (t-BuOH or t-AmOH) in the enantioselective allylboration reaction of isatins has also been shown on the basis of a kinetics study and computational calculations by favoring the transesterification of the 2-allyl-1,3,2-dioxaborolane with BINOL via proton transfer processes.

3.
J Phys Chem A ; 127(50): 10555-10569, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38086177

RESUMO

In this work, five novel A-π-D-π-A type molecules D1-D5 were designed by adding unusual benzothiadiazole derivatives as π-spacer blocks to the efficient reference molecule DRCN5T for application as donor materials in organic solar cells (OSCs). Based on a density functional theory approach, a comprehensive theoretical study was performed with different functionals (B3LYP, B3LYP-GD3, B3LYP-GD3BJ, CAM-B3LYP, M06, M062X, and wB97XD) and with different solvent types (PCM and SMD) at the extended basis set 6-311+g(d,p) to evaluate the structural, optoelectronic, and intramolecular charge transfer properties of these molecules. The B3LYP-GD3BJ hybrid functional was used to optimize the studied molecules in CHCl3 solution with the SMD model solvent as it provided the best results compared to experimental data. Transition density matrix maps were simulated to examine the hole-electron localization and the electronic excitation processes in the excited state, and photovoltaic parameters including open-circuit photovoltage and fill factor were investigated to predict the efficiency of these materials. All the designed materials showed promising optoelectronic and photovoltaic characteristics, and for most of them, a red shift. Out of the proposed molecules, [1,2,5]thiadiazolo[3,4-d]pyridazine was selected as a promising π-spacer block to evaluate its interaction with PC61BM in a composite to understand the charge transfer between the donor and acceptor subparts. Overall, this study showed that adding π-spacer building blocks to the molecular structure is undoubtedly a potential strategy to further enhance the performance of donor materials for OSC applications.

4.
Int J Mol Sci ; 24(13)2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37446253

RESUMO

Liquid biopsy and circulating tumor cell (CTC) screening has gained interest over the last two decades for detecting almost all solid malignancies. To date, the major limitation in terms of the applicability of CTC screening in daily clinical practice is the lack of reproducibility due to the high number of platforms available that use various technologies (e.g., label-dependent versus label-free detection). Only a few studies have compared different CTC platforms. The aim of this study was to compare the efficiency of four commercially available CTC platforms (Vortex (VTX-1), ClearCell FX, ISET, and Cellsearch) for the detection and identification of uveal melanoma cells (OMM 2.3 cell line). Tumor cells were seeded in RPMI medium and venous blood from healthy donors, and then processed similarly using these four platforms. Melan-A immunochemistry was performed to identify tumor cells, except when the Cellsearch device was used (automated identification). The mean overall recovery rates (with mean recovered cells) were 39.2% (19.92), 22.2% (11.31), 8.9% (4.85), and 1.1% (0.20) for the ISET, Vortex (VTX-1), ClearCell FX, and CellSearch platforms, respectively. Although paramount, the recovery rate is not sufficient to assess a CTC platform. Other parameters, such as the purpose for using a platform (diagnosis, genetics, drug sensitivity, or patient-derived xenograft models), reproducibility, purity, user-friendliness, cost-effectiveness, and ergonomics, should also be considered before they can be used in daily clinical practice and are discussed in this article.


Assuntos
Melanoma , Células Neoplásicas Circulantes , Neoplasias Uveais , Humanos , Células Neoplásicas Circulantes/patologia , Reprodutibilidade dos Testes , Melanoma/patologia , Neoplasias Uveais/diagnóstico , Neoplasias Uveais/patologia , Biomarcadores Tumorais/metabolismo
5.
Undersea Hyperb Med ; 49(4): 495-505, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36446295

RESUMO

Introduction: We aimed to assess the efficacy and safety of a standardized hyperbaric oxygen (HBO2) therapy protocol in patients with retinal artery occlusion (RAO). Methods: A retrospective study was conducted in our tertiary care center from July 2016 to September 2019. Patients experiencing central RAO and branch RAO for less than seven days were included. Once the diagnosis was made, patients were urgently referred to the HBO2 department to receive a first 90-minute HBO2 session at a pressure of 2.5 ATA. Patients underwent two daily sessions seven days a week for at least 15 days. If no reperfusion was seen on fluorescein angiography on Day 15, treatment was continued for an additional week with an assessment on Day 21. The primary endpoint was BCVA improvement defined as a decrease by 0.3 logMAR at one month. Results: Twenty-eight patients were included during the study period. Fifty-seven percent of patients were treated more than 12 hours after the onset of the first symptoms. The mean BCVA was 1.5 logMAR at the time of referral and improved to 0.9 logMAR after HBO2 (p=0.001). A multivariate analysis identified a high blood pressure (p=0.039) and a low initial BCVA (p=0.005) as poor prognostic factors. Conclusion: Performing HBO2 sessions twice daily at a pressure of 2.5 ATA appears to be an effective and safe treatment for RAO.


Assuntos
Oxigenoterapia Hiperbárica , Oclusão da Artéria Retiniana , Humanos , Oxigenoterapia Hiperbárica/efeitos adversos , Estudos Retrospectivos , Oclusão da Artéria Retiniana/terapia , Oxigênio , Angiofluoresceinografia
6.
J Org Chem ; 86(7): 4917-4931, 2021 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-33725439

RESUMO

Aldol addition of α-triisopropylsilyl-α-diazoacetone (TIPS-diazoacetone), promoted by excess lithium diisopropylamide (LDA), was developed and applied to the synthesis of original C-TIPS diazoaldols, C-TIPS diazoketols, and a related Mannich-type product. An unprecedented mechanistic pathway has been proposed, involving a lithiated triazene intermediate resulting from the nucleophilic addition of LDA on the diazo moiety, supported by experimental results and DFT calculations.

7.
J Org Chem ; 86(12): 8041-8055, 2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-33960779

RESUMO

Enantiopure (R) and (S) cyclic α,α-disubstituted amino acid derivatives displaying a δ-valerolactam side chain were prepared from a common isoxazolidine precursor. The (R)-configured δ-valerolactam 11 was converted into diastereoisomeric pseudopeptides to investigate its ability to induce secondary structures in peptidomimetics. Conformational studies of these pseudopeptides were carried out in the solid state (X-ray diffraction), in solution (NMR analyses), and in silico (computer-aided conformational analysis), which demonstrated that such quaternary amino acids induce ß-turn conformations stable enough to be retained in polar media (DMSO). Incorporation of this new type of α,α-disubstituted amino acid into a representative pseudopeptidic sequence by N- then C-elongation and N-debenzylation is also described herein and could serve for the synthesis of various structured peptidomimetics.


Assuntos
Aminoácidos , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Estrutura Secundária de Proteína , Difração de Raios X
8.
Graefes Arch Clin Exp Ophthalmol ; 259(9): 2827-2835, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33770270

RESUMO

PURPOSE: The purpose of this study is to report our experience with the use of artificial dermis grafts for orbital socket reconstruction following orbital exenteration (OE). METHOD: A retrospective study was conducted in our ocular oncology centre from May 2018 to June 2020 in patients undergoing OE for orbital malignancies in whom an artificial dermis device (Integra® template, 2 layers) was used for reconstruction. Data recorded included demographics, previous and adjuvant treatments, aetiologies, surgical procedure, surgical reconstruction, complications and follow-up. The main outcome measure was the time between OE and the full granulation of the cavity. RESULTS: Ten patients (mean age, 71.3 years [43-92]) were included. Tumours originated from the conjunctiva (n = 5, 50%), eyelid (n = 3, 30%) and orbit (n = 2, 20%). Nine patients underwent total OE, and one required enlarged OE. Orbital reconstruction was performed using an artificial dermis alone (n = 9, 90%) or combined with regional flaps (n = 1, 10%). The mean granulation time was 3.3 weeks (2-4). Three (30%) patients received adjuvant radiotherapy 1 month post-surgery. The mean time to spontaneous epithelialization was 9.4 weeks (6-12). Preoperative and postoperative radiotherapy was not associated with a delayed epithelialization of the socket (p = 0.463 and p = 0.236, respectively). One (10%) and 2 (20%) patients experienced postoperative socket infection and an ethmoidal fistula, respectively. The mean follow-up was 11.6 months (6-16). CONCLUSION: Using artificial dermis grafts alone or with regional flaps appears to be a viable surgical procedure for orbital socket reconstruction. They reduce surgical morbidity and hospital stay. Preoperative and postoperative radiotherapy does not seem to delay socket healing.


Assuntos
Procedimentos de Cirurgia Plástica , Idoso , Olho Artificial , Humanos , Órbita/cirurgia , Exenteração Orbitária , Estudos Retrospectivos , Retalhos Cirúrgicos
9.
Org Biomol Chem ; 17(37): 8467-8485, 2019 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-31498368

RESUMO

This review provides an overview of the applications of α-halogenoacetamides in domino and cycloaddition reactions. α-Halogenoacetamides are versatile building blocks that can lead to a wide variety of complex aza-heterocycles of biological interest when engaged in domino and/or cycloaddition reactions. The reactivity and the reaction conditions involved for these species (solvent, base, etc.) are closely related to the substituent onto the nitrogen atom of the amide: N-alkyl α-halogenoacetamides usually act as formal 1,3-dipoles in domino processes whereas N-alkoxy derivatives often react as real 1,3-dipoles via the formation of aza-oxyallyl cation species. This important modulation of the reactivity of these compounds opens the way to a large panel of reactions and therefore to a large diversity of aza-heterocycles.

10.
Chemistry ; 24(53): 14069-14074, 2018 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-30035833

RESUMO

A stereospecific Mizoroki-Heck cross-coupling of differently substituted glycals with haloarenes resulting in the exclusive formation of either α- or ß-aryl-C-glycosides depending solely on the configuration at C3 was achieved. The reaction was easy to set up because no specific precautions were required concerning moisture or oxygen, and it proceeded by a chirality transfer from C3 to C1. After optimization of cross-coupling conditions, various prepared glycals (7 examples) and arenes (10 examples) were tested, leading stereospecifically to the corresponding aryl-C-glycosides with a carbonyl group at C3, thus opening up new horizons for the total synthesis of glycosylated natural products.

11.
Orbit ; 37(2): 94-96, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29040036

RESUMO

An 86-year-old patient was hospitalized for fever and left acute orbital syndrome (red eye with moderate visual impairment, chemosis, ophthalmoplegia without proptosis, or any fundus involvement). CT scan showed superior ophthalmic vein and cavernous sinus enlargement complicating ipsilateral sphenoidal sinusitis. Magnetic resonance imaging (MRI) demonstrated the left cavernous sinus thrombosis extended to the ipsilateral jugular vein and transversal sinus (Lemierre syndrome). Intravenous broad-spectrum antibiotics and curative anticoagulation were prescribed. Blood cultures allowed the identification of Streptococcus intermedius and Staphylococcus warneri species. Evolution was favorable and the patient was discharged 3 weeks after. Antibiotics and anticoagulation were carried out for a total duration of 4 and 12 weeks, respectively. Lemierre syndrome is a potentially life-threatening emergency rarely encountered; thus, ophthalmologists should be cognizant of clinical and radiological features. Broad-spectrum antibiotics are the mainstay of treatment. Curative anticoagulation may be added if no blood coagulation disorder nor bleeding on neuroimaging has been identified.


Assuntos
Trombose do Corpo Cavernoso/diagnóstico por imagem , Veias Jugulares/patologia , Síndrome de Lemierre/diagnóstico por imagem , Doenças dos Seios Paranasais/diagnóstico por imagem , Infecções Estafilocócicas/diagnóstico por imagem , Infecções Estreptocócicas/diagnóstico por imagem , Idoso de 80 Anos ou mais , Antibacterianos/uso terapêutico , Anticoagulantes/uso terapêutico , Trombose do Corpo Cavernoso/tratamento farmacológico , Trombose do Corpo Cavernoso/microbiologia , Humanos , Síndrome de Lemierre/tratamento farmacológico , Síndrome de Lemierre/microbiologia , Imageamento por Ressonância Magnética , Masculino , Doenças dos Seios Paranasais/tratamento farmacológico , Doenças dos Seios Paranasais/microbiologia , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Staphylococcus/isolamento & purificação , Infecções Estreptocócicas/tratamento farmacológico , Infecções Estreptocócicas/microbiologia , Streptococcus intermedius/isolamento & purificação , Tomografia Computadorizada por Raios X
12.
Beilstein J Org Chem ; 14: 2949-2955, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30546479

RESUMO

In this paper, a new access to several chiral 3-aminoglycals as potential precursors for glycosylated natural products is reported from a common starting material, (-)-methyl-L-lactate. The stereodivergent strategy is based on the implementation of a ring-closing metathesis of vinyl ethers as key step of reaction sequences developed.

13.
J Org Chem ; 82(11): 5798-5809, 2017 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-28467063

RESUMO

The access to new oxazolo[3,2-d][1,4]oxazepin-5(3H)-ones starting from α-bromoamido alcohols and Michael acceptors under mild conditions is presented. This domino process proved to be chemo-, regio-, and stereoselective and allows the formation of a large diversity of highly functional 7-membered rings in good yields up to 95%. The complete shift of the regioselectivity of the intermediate enolate from a C-C to a C-O bond formation, contrary to the already known alkylations of such ambident nucleophiles, is mostly triggered by steric effects. The last step of the sequence was modeled by DFT giving some important insights for this C-C vs C-O bond shift.

14.
Angew Chem Int Ed Engl ; 56(41): 12424-12458, 2017 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-28436571

RESUMO

The Robinson annulation is a reaction that has been useful for numerous syntheses since its discovery in 1935, especially in the field of steroid synthesis. The products are usually obtained after three consecutive steps: the formation of an enolate (or derivative), a conjugate addition, and an aldol reaction. Over the years, several methodological improvements have been made for each individual step or alternative routes have been devised to access the Robinson annulation products. The first part of this Review outlines the most relevant developments towards the formation of monocarbonyl-derived Robinson annulation products (MRA products, MRAPs) and activated monocarbonyl-derived Robinson annulation products (AMRA products, AMRAPs). The following sections are then devoted to the diastereoselective and enantioselective synthesis of these products, while the last section describes the enantiomeric resolution of racemic mixtures.

17.
Chemistry ; 21(7): 2966-79, 2015 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-25524225

RESUMO

This paper describes the synthesis of both polysubstituted oxazolo-pyrrolidinones and -piperidinones by a domino process. The methodology is based on the reaction between hydroxyl halogenoamides and Michael acceptors, which leads efficiently to bicyclic lactams. The process is compatible with unsymmetrical electron-withdrawing groups on the Michael acceptor, which allows the formation of two contiguous and fully controlled tertiary and quaternary stereocenters. In the case of tetrasubstituted Michael acceptors, two adjacent quaternary stereocenters are formed in good yield. Starting from (R)-phenylglycinol derived amides results in the formation of enantioenriched bicyclic lactams in low to good yields and with high levels of stereoselectivity, thus greatly increasing the scope and interest of this strategy. The origins of chirality transfer and diastereoselectivity were studied by DFT calculations and have been attributed to a kinetic control in one of the last two steps of the reaction sequence. This selectivity is dependent upon both the substituents on the Michael acceptor and the sodium cation chelation.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes/síntese química , Lactamas/síntese química , Compostos Bicíclicos Heterocíclicos com Pontes/química , Ligação de Hidrogênio , Lactamas/química , Modelos Moleculares , Conformação Molecular , Oxazóis/síntese química , Oxazóis/química , Piperidinas/síntese química , Piperidinas/química , Pirrolidinonas/síntese química , Pirrolidinonas/química , Estereoisomerismo
18.
J Org Chem ; 79(8): 3414-26, 2014 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-24605848

RESUMO

A catalytic 1,3-dipolar cycloaddition between carboalkoxy ketonitrones and methacrolein under the effect of chiral ruthenium Lewis acid (R,R-1) was developed with high regio-, diastereo-, and enantiocontrol. The diastereochemical outcome of the cycloaddition reaction is marked by a significant solvent effect, and a divergent endo or exo control can be tuned by an appropriate choice of both the solvent and the N- and O-substituents of the ketonitrone. A rationale of the solvent effect, based on the computational study of the interactions between the methacrolein-Ru complex and its counteranion (SbF6(-)), is proposed to explain the selectivities obtained.

19.
ChemistryOpen ; : e202400115, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38752792

RESUMO

The synthesis of polycyclic γ- and δ-lactams bearing up to four contiguous fully controlled stereocenters is presented. For that purpose, we developed an original approach based on the use of 2,3-epoxyamides in domino reactions by taking advantage of the nucleophilic nitrogen atom and electrophilic epoxide. In reaction with enol ethers bearing gem bis-electrophiles on the double bond as Michael acceptors, four different reaction pathways were observed. They all started with a domino oxa-Michael/aza-Michael/epoxide opening sequence and depending on substrates engaged could be followed either by a lactonization or a hemiketalization/retro-aldol cascade. Thus, four original fully-substituted piperidine- or pyrrolidine-2-one scaffolds were selectively synthesized in good to high yields. Moreover, these polycyclic lactams were obtained in high stereo- and chemo-selectively highlighting the efficiency and molecular diversity offered by this new methodology that should offer various synthetic opportunities in the future.

20.
Semin Ophthalmol ; : 1-9, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38661124

RESUMO

PURPOSE: To report new indications for deep temporalis fascia (DTF) grafts in the ophthalmic field. METHODS: Monocentric retrospective interventional case series study. All the patients who underwent a DTF graft in an unpublished new indication over the study period (May 2020-October 2023) were included. For each patient, gender, age, graft indication, outcomes, complications, and follow-up duration were collected. In most cases, the DTF graft was covered by a vascularized flap. RESULTS: Eight patients underwent a DTF graft over the study period. The indications were: radiotherapy-induced scleral necrosis in three cases, tendinoplasty to replace the inferior rectus muscle tendon invaded by a locally advanced conjunctival carcinoma in one case, Ahmed glaucoma valve tube exposure in one case, intraocular lens with scleral fixation exposure in one case, orbital cerebrospinal fluid fistula (orbitorrhea) in one case, and post-traumatic complete corneal graft loss in one case. The DTF graft was successful in 87.5% of cases after a mean follow-up of 11.4 months. No complications were observed. CONCLUSIONS: DTF graft is a highly versatile graft that can be easily harvested. New indications for DTF grafts may include the repair of radiotherapy-induced scleral necrosis, the creation of oculomotor tendon and the temporary packing of large ocular tissue loss in an emergency context. Further studies with a longer follow-up are needed to confirm our preliminary results.

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