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1.
Eplasty ; 24: e27, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38846502

RESUMEN

Background: Intraosseous hemangiomas are rare benign tumors comprising fewer than 1% of all osseous tumors; even more uncommon are intraosseous hemangiomas of the zygomatic bone. This case reports a multidisciplinary approach for excision and reconstruction of an intraosseous hemangioma of the zygomatic bone in a 54-year-old female. Methods: Multidisciplinary approach with both otolaryngology head and neck surgery and oculofacial plastics and reconstructive surgery included right lateral canthotomy and right transconjunctival orbitotomy with en-bloc excision of the zygomatic arch, followed by reconstruction of the orbital rim, orbital floor, and eyelid with Medpor implant. Results: Final surgical pathology was consistent with intraosseous hemangioma of the zygomatic bone. At 4-month follow-up, the patient was healing well with good midface projection and without any visual deficits. Conclusions: A multidisciplinary coordinated case allowed us to meet the standard of maintaining cosmesis and function while undergoing resection of a rare tumor involving a key facial structure-the zygoma. Involvement of oculofacial plastics and reconstructive surgery service allowed for advanced eyelid reconstruction techniques to limit any functional impairment to our patient with deliberate choice of implant material for well-adhered, durable, and aesthetically optimal reconstruction of the right malar eminence, lateral orbital rim, and orbital floor defect. The postoperative result through the multidisciplinary approach was a near symmetrical facial reconstruction without any associated eyelid or globe abnormalities.

2.
J Org Chem ; 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38814738

RESUMEN

Despite the wide utility of hydroxylamines in organic synthesis, relatively few are commercially available, and there is a need for direct, efficient, and selective methods for their synthesis. Herein, we report two complementary methods to accomplish direct oxidation of secondary amines using UHP as an oxidant. The first method uses 2,2,2-trifluoroethanol (TFE) and a large excess of amine. Isolation of hydroxylamine products is enabled by selective salt formation, and recovery of excess amine is demonstrated. The second method uses hexafluoroacetone as an additive and is highlighted by the 1:1 stoichiometry between the oxidant and amine.

3.
JAMA Otolaryngol Head Neck Surg ; 150(3): 277-278, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38236618

RESUMEN

This case report describes a healthy man in his 40s who presented with a 1-year history of snoring, sleep apnea, dysphonia, and dysphagia owing to a large mass of the posterior pharynx and was diagnosed with an inflammatory rhabdomyoblastic tumor.


Asunto(s)
Neoplasias , Síndromes de la Apnea del Sueño , Humanos , Faringe/patología , Ronquido/patología
4.
Org Lett ; 25(17): 3045-3048, 2023 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-37097727

RESUMEN

Aminoboronic acid derivatives can serve as versatile synthetic intermediates and pharmacophores but remain difficult to synthesize. Herein we report a synthesis of the ß-aminoboronic acid motif via anti-Markovnikov hydroamination of vinylboronates. This reaction benefits from the activating effect of the boronate substituent and forms novel BON-containing heterocycles, oxazaborolidine zwitterions. A computational study is included to help determine the effects of alkene boron substitution. Derivatization reactions also support the synthetic utility of the oxazaborolidine adducts.

6.
Chem Sci ; 13(24): 7264-7268, 2022 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-35799811

RESUMEN

Metal- or acid-catalyzed intramolecular hydroamination and Cope-type intramolecular hydroamination, a distinct concerted approach using hydroxylamines, typically suffer from significant synthetic limitations. Herein we report a process for intramolecular hydroamination that uses a redox-enabled strategy relying on efficient in situ generation of hydroxylamines by oxidation, followed by Cope-type hydroamination, then reduction of the resulting pyrrolidine N-oxide. The steps are performed sequentially in a single pot, no catalyst is required, the conditions are mild, the process is highly functional group tolerant, and no chromatography is generally required for isolation. A robustness screen and a gram-scale example further support the practicality of this approach.

7.
Facial Plast Surg ; 37(3): 348-353, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32942313

RESUMEN

Opposing facial features between animated villains and heroes have historically been used to demonstrate contrasting morality between characters, and this could have an impact on how humans view someone as good or evil in everyday life. Studies have been done investigating classic dermatologic features of villainous characters. This principle can be applied to nasal features as well. A search for "top animated characters" was performed. Characters were chosen from American Film Institute's "The Top Tens," Rolling Stone's "25 Best Pixar Movie Characters," and Screenrant's "The 30 Best Animated Movie Characters of All Time." Twenty villains and twenty hero counterparts from respective films were chosen. Classic nasal features were analyzed. Twenty villains (14 male, 6 female) and 20 heroes (12 male, 8 female) were analyzed. Sixteen villains (80%) had greater than normal nasal frontal angle versus 18 heroes (90%). Thirteen villains (65%) had an acute nasolabial angle versus two heroes (10%). Two villains (10%) had excess columellar show versus seven heroes (35%). Seven villains (35%) and one hero (5%) had a dorsal hump. Twelve villains (60%) had an overprojected chin versus three heroes (15%). Villains in pre-2000s films more frequently had a dorsal hump, overprojected chin, ptotic tip, pollybeak deformity, and bulbous tip. Heroes in pre-2000s films more frequently had an overrotated tip. Villains and heroes commonly have a greater than normal nasofrontal angle. Villains more commonly have an acute nasolabial angle, underrotated tip, overprojected chin, dorsal hump, and pollybeak deformity. Heroes more commonly have a large nasolabial angle and overrotated tip. Further research in conjunction with psychologists is required to obtain concrete data on how this affects whether an individual in real life is seen as good or evil, and the impact this has on interactions in society, including in the medical field.


Asunto(s)
Películas Cinematográficas , Tabique Nasal , Femenino , Humanos , Masculino , Estados Unidos
8.
Angew Chem Int Ed Engl ; 59(51): 23188-23197, 2020 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-32767511

RESUMEN

1,3-Dipoles are commonly used in [3+2] cycloadditions, whereas isoelectronic uncharged dipole variants remain underdeveloped. In contrast to conventional 1,3-dipoles, uncharged dipole equivalents form zwitterionic cycloadducts, which can be exploited to build further molecular complexity. In this work, the first cycloadditions of oxygen-substituted isocyanates (O-isocyanates) were studied experimentally and by DFT calculations. This unique cycloaddition strategy provides access to a novel class of heterocycle aza-oxonium ylides through intramolecular and intermolecular cycloadditions with alkenes. This allowed a systematic study of the reactivity of the transient aza-oxonium ylide intermediate, which can undergo N-O bond cleavage followed by nitrene C-H insertion, and the formation of ß-lactams or isoxazolidinones upon varying the structure of the alkene or O-isocyanate reagents.

9.
Chemistry ; 26(1): 171-175, 2020 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-31614052

RESUMEN

Novel oxime-ether tethered cyclopropanes, when exposed to Yb(OTf)3 and heat, annulate to generate hydropyrrolo-oxazines products that can be taken to their respective pyrrolidines via hydrogenative N-O bond cleavage. The hydropyrrolo-oxazines are generated in a diastereoselective manner isolating the cis or trans product based on the temperature of the reaction. 20 examples of selective cis and trans hydropyrrolo-oxazines were generated in high yields by temperature control.

10.
Org Lett ; 19(24): 6574-6577, 2017 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-29166028

RESUMEN

Oxy-carbamate O-isocyanate precursors facilitate access to synthetically valuable N-oxyureas via substitution with amines. This work exploits the reactivity of suitable O-isocyanate precursors, identified by a thorough study highlighting the different reactivity of isocyanate masking groups. This led to bench-stable O-isocyanate precursors, offering improved versatility in the synthesis of N-oxyureas, and demonstrates the controlled reactivity of masked O-isocyanates. Suitable precursors also enabled the first example of Cope-type hydroamination of unsaturated hydroxyureas.

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