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1.
Ann Card Anaesth ; 26(2): 211-214, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37706390

RESUMO

The role of extracorporeal membrane oxygenation (ECMO) and its indications in stage I Norwood palliation are controversial. The decision to initiate ECMO and its timing remains difficult with no definitive cut-off points or evidence-based guidelines. It varies on a case-to-case basis. We report a case where the use of ECMO was beneficial after stage I Norwood palliation with severe ventricular dysfunction. The systemic-to-pulmonary artery shunt was kept open to balance the systemic and pulmonary circulations. Cerebral oximetry can be useful as an additional monitoring modality to guide management, monitor cerebral perfusion, and help detect cerebral steal.


Assuntos
Oxigenação por Membrana Extracorpórea , Síndrome do Coração Esquerdo Hipoplásico , Humanos , Síndrome do Coração Esquerdo Hipoplásico/cirurgia , Síndrome do Coração Esquerdo Hipoplásico/diagnóstico , Oximetria , Circulação Cerebrovascular , Procedimentos Cirúrgicos Vasculares , Resultado do Tratamento
2.
J Org Chem ; 88(13): 7988-7997, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37222447

RESUMO

A rhodium-catalyzed oxidative C-H/N-H dehydrogenative [3 + 2] annulation strategy has been reported between anilines and N-allylbenzimidazole for the synthesis of 2-methylindole scaffolds. An N-allylbenzimidazole has been used as a 2C synthon for the synthesis of indole, and more importantly, this transformation involves the cleavage of the thermodynamically stable C-N bond of allylamine. Detailed mechanistic studies have been performed and a key intermediate was detected in HRMS. This transformation proceeds through a cascade of C(sp2)-H allylation followed by intramolecular cyclization.


Assuntos
Ródio , Ródio/química , Catálise , Indóis , Oxirredução
3.
J Org Chem ; 88(2): 952-959, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36606375

RESUMO

Herein, we report the annulation of indole-2-carboxamides with bicycloalkenes, to synthesize ß-carboline-1-one derivatives under mild conditions. The commercially available ruthenium catalyst was used for the reaction. This reaction tolerates a wide range of functional groups and affords a good yield of ß-carboline-1-one derivatives. A reversible cyclometalation pathway was found to be operative in the mechanistic study.

4.
Chem Commun (Camb) ; 59(2): 199-202, 2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36476727

RESUMO

A Rh-catalyzed C(sp2)-H propenylation has been reported by taking N-allyl benzimidazole as an allylamine congener. This transformation has been observed for the first time, where a tandem process of C-H allylation followed by alkene isomerization delivers a highly stereoselective trans-propenylated product. Detailed mechanistic studies including the characterization of rhodacycle-intermediates have been conducted to understand the mechanism.


Assuntos
Alilamina , Ródio , Ródio/química , Catálise , Alcenos/química
5.
Org Lett ; 24(33): 6122-6127, 2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-35952663

RESUMO

A Ni-catalyzed C6 followed by C5 cascade C-H activation/[2 + 2 + 2] annulation of 2-pyridone with alkynes has been achieved. A change in the reaction pathway was achieved by tuning the reaction conditions and incorporating a directing group. A wide variety of substrates and alkynes are amenable to this transformation. The key to success for this transformation is the use of sodium iodide as an additive. More importantly, we detected the five-membered metallacycle intermediate through HRMS wherein iodide is ligated to the metal.

6.
J Org Chem ; 87(9): 6189-6201, 2022 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-35467333

RESUMO

Herein, the ruthenium-catalyzed regioselective sp2(C-H) monoalkenylation of N-arylpyridones has been demonstrated, where the pyridone was utilized as a weakly coordinating directing group. Importantly, the current methodology has been effectively applied to the synthesis of many drug analogues such as pirfenidone, naproxen, ibuprofen, geraniol, umbelliferone, pregnenolone, and estrone. This methodology tolerates a wide range of functional groups and yields up to 93% yield. A six-membered ruthenium complex was also detected by HRMS.


Assuntos
Compostos Heterocíclicos , Rutênio , Catálise , Piridonas , Rutênio/química
7.
Aesthetic Plast Surg ; 46(5): 2248-2257, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35106655

RESUMO

INTRODUCTION: The superior labial artery (SLA) is a facial artery (FA) that drains into the peri-oral region (dangerous area of face). Owing to the recent rise in the demand for reconstructive procedures and filler injections in this region, it is important to understand its arterial topography. This paper aims to study the embranchment pattern of the labial arteries in the eastern Indian population. METHOD: An observational study using conventional dissection and dry dye injection methods was conducted to visualize the facial and superior labial arteries in 56 hemifaces. The origin, morphometry (length and diameter), branching pattern, and termination of the arteries were recorded and compared with the existing data. RESULTS: Two hemifaces were excluded from analysis (vessels damaged in dissection); in the remaining 54, a single SLA was present in all samples originating at a mean distance of 1.29 ± 0.32 cm from oral commissure (68.51% originating above). Lee type II (independent SLA giving off alar branch) was the predominant pattern (56.2%), followed by type I (independent SLA and alar branches, 33%) and type III (FA terminating as SLA, 10.8%). The average length of SLA was 4.75 ± 1.28 cm and 4.56 ± 0.78 cm on the right and left sides, respectively. CONCLUSION: The SLA is highly variable in occurrence, course, and depth, sometimes even occurring unilaterally; therefore, any intervention in this region should be done with caution. Since the SLA was not found subcutaneously at the vermillion border, the intradermal and the subcutaneous injections used here are relatively safer. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Assuntos
Artérias , Lábio , Humanos , Lábio/cirurgia , Cadáver , Artérias/anatomia & histologia , Face/irrigação sanguínea , Injeções Subcutâneas
8.
Org Lett ; 24(3): 848-852, 2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35040656

RESUMO

An earth-abundant and inexpensive Mn(I)-catalyzed alkylation of 2-pyridone with maleimide has been reported for the first time, in contrast to previously reported Diels-Alder products. Notably, an unexpected rearrangement has been discovered in the presence of acetic acid, which also provides a unique class of compounds bearing three different N-heterocycles with an all-carbon quaternary center. Furthermore, single crystal X-ray and HRMS revealed a five-membered manganacycle intermediate. This methodology tolerates a wide variety of functional groups delivering the alkylated products in moderate to excellent yields.

9.
ACS Nano ; 15(12): 20203-20213, 2021 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-34878256

RESUMO

We map spatially correlated electrical current on the stacking boundaries of pristine and doped hexagonal boron nitride (hBN) to distinguish from its insulating bulk via conductive atomic force microscopy (CAFM). While the pristine edges of hBN show an insulating nature, the O-doped edges reveal a current 2 orders of higher even for bulk layers where the direct transmission through tunnel barrier is implausible. Instead, the nonlinear current-voltage characteristics (I-V) at the edges of O-doped hBN can be explained by trap-assisted lowering of the tunnel barrier by adopting a Poole-Frenkel (PF) model. However, in the stacked heterostructure with multilayer graphene (MLG) on top, the buried edge of pristine hBN shows a signature of electron conduction in the scanning mode which contradicts the first-principle calculation of spatial distribution of local density of states (LDOS) data. Enhancement of friction between the Pt-tip and MLG at the step-edge of the heterostructure while scanning in the contact mode has prompted us to construct a phenomenological model where the localization of opposite surface charges on two conducting plates (MLG and Si substrate) containing a dielectric film (hBN) with negatively charged defects creates an internal electric field opposite to the external electric field due to the applied voltage bias in the CAFM setup. An equivalent circuit with a parallel resistor network based on a vertical conducting channel through the MLG/hBN edge and an in-plane surface carrier transport through MLG can successfully analyze the current maps on pristine/doped hBN and the related heterostructures. These results yield fundamental insight into the emerging field of insulatronics in which defect-induced electron transport along the edge can be manipulated in an 1D-2D synergized insulator.

10.
Org Lett ; 23(23): 9041-9046, 2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34788053

RESUMO

Herein, nickel-catalyzed synthesis of polyarylcarbazole through sequential C-H bond activations has been described. Regioselective indole C2/C3 functionalization has been achieved in the presence of indole C7-H, which is quite challenging. In addition, this approach also gives easy access to building a heteropolycyclic motif through C6/C7 C-H functionalization of indoline. This methodology is not limited to aromatic internal alkynes as coupling partners; aliphatic alkynes have also shown good tolerance. Notably, during the optimization the catalytic enhancement with sodium iodide as an additive has been observed. We have also studied the photophysical properties of these highly conjugated molecules.

11.
Indian J Thorac Cardiovasc Surg ; 37(5): 619, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34515693

RESUMO

[This corrects the article DOI: 10.1007/s12055-021-01161-w.].

12.
Indian J Thorac Cardiovasc Surg ; 37(5): 521-525, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34511758

RESUMO

Arterial switch operation for transposition of great arteries (TGA) is the choice of surgical treatment for this condition. Conventional "open" coronary transfer technique has been commonly employed with good results in experienced hands. A modified "closed" technique of coronary transfer, with a more accurate coronary artery placement taking into account a distended aorta, along with anterior interrupted sutures to reduce purse stringing and other advantages is described.

13.
J Org Chem ; 86(14): 9444-9454, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34227380

RESUMO

Co(III)-catalyzed alkenylation of 2-pyridones by using terminal alkyne as a reaction partner with high regioselectivity has been demonstrated for the first time. The reaction conditions are mild and compatible with a wide range of substrate combinations. It also shows good functional group tolerance. It proceeds through cyclometalation followed by alkyne insertion and protodemetalation steps. The formation of five- and seven-membered cobaltacycle intermediates was also detected through high-resolution mass spectrometry.


Assuntos
Alcinos , Cobalto , Catálise , Piridonas
14.
Ann Gastroenterol ; 34(3): 316-322, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33948055

RESUMO

BACKGROUND: Publication history is a key factor in securing academic promotion, but historical underrepresentation of women in gastroenterology may be an ongoing obstacle to achieving gender parity in leadership positions. METHODS: We carried out a cross-sectional study of gastroenterology programs in the United States, with data including faculty and trainee names, leadership positions, Hirsch indices, and year of first gastroenterology certification gathered from 1 February 2020 to 1 March 2020. Our outcomes of interest were: 1) sex representation in various leadership positions in academic gastroenterology departments; and 2) mean difference in Hirsch indices between men and women, for which we used univariate and multivariate regression models. RESULTS: Our cohort included 3655 faculty members and trainees across 163 academic gastroenterology programs in the United States. Women comprised 28.7% (1049/3655) of the cohort, including 713/2657 (26.8%) of faculty and 56/289 (19.4%) of all fellowship program directors and divisional/departmental chairs and chiefs. Male faculty had higher mean Hirsch indices compared to women (11.4 vs. 5.5, P<0.001), and when adjusted for year of first gastroenterology certification, men had a larger Hirsch index by 2.8 (95% confidence interval 1.3-4.1, P<0.001). Women were also underrepresented in various subspecialties of gastroenterology, particularly advanced endoscopy. CONCLUSIONS: Women in academic gastroenterology remain underrepresented in leadership positions and have lower Hirsch indices than men. Our findings may stem not only from differences in mentorship and career goals, but also from underlying structural factors that disadvantage women.

15.
Indian Heart J ; 73(2): 196-204, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33865518

RESUMO

BACKGROUND: Potts shunt has been suggested as an effective palliative therapy for patients with pulmonary artery hypertension (PAH) not associated with congenital heart disease. MATERIALS AND METHODS: This is a prospective single-center study performed to assess outcomes of Potts shunt in patients with PAH who are in functional class III or IV. RESULTS: 52 patients in functional class III/IV with pulmonary arterial hypertension without significant intra or extracardiac shunt on maximal medical therapy were evaluated and counseled for undergoing Potts shunt/patent ductus arteriosus (PDA) stenting. 16/52 patients (13 females) consented for the procedure; 14 patients underwent surgical creation of Potts, and 2 underwent transcatheter stenting of PDA, which physiologically acted like a Potts shunt. Standard medical therapy was continued in patients who did not consent for the procedure. 12/16 patients survived the procedure. Patients who did not survive the procedure were older, with severe right ventricular systolic dysfunction, and functional class IV. Patients who survived the procedure were followed up in the pulmonary hypertension clinic. The Median follow-up was 17 months (1-40 months). 11/13 patients discharged after the operation showed sustained clinical, echocardiographic, and biochemical improvement, which reduced need for pulmonary vasodilator therapy in 10/13 patients. There was one death in the follow-up period 16 months post-surgery due to lower respiratory tract infection. CONCLUSION: Potts shunt is feasible in patients with PAH without significant intra or extracardiac shunts. It can be done safely with an acceptable success rate. Patient selection, preoperative stabilization, and meticulous postoperative management are essential. It should be performed at the earliest sign of clinical, echocardiographic, or laboratory deterioation for optimal outcomes. Long-term follow-up is required to see a sustained improvement in functional class and the need for a lung transplant in the future.


Assuntos
Hipertensão Arterial Pulmonar , Artéria Pulmonar , Anastomose Cirúrgica , Feminino , Humanos , Cuidados Paliativos , Estudos Prospectivos , Artéria Pulmonar/cirurgia , Resultado do Tratamento
16.
J Org Chem ; 86(9): 6551-6565, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33900753

RESUMO

A ruthenium(II)-catalyzed cross dehydrogenative annulation of N-(7-azaindole)benzamides with maleimides has been demonstrated. Herein, we have explored the use of N-amino-7-azaindole as a new bidentate directing group for dehydrogenative [4 + 2] annulation. This method works efficiently, affording a variety of pharmacologically useful 7-azaindole-based isoquinolones and showing a wide functional group tolerance.


Assuntos
Rutênio , Benzamidas , Catálise , Indóis , Maleimidas
17.
Indian J Thorac Cardiovasc Surg ; 37(Suppl 1): 26-35, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33584025

RESUMO

Hypoplastic left heart syndrome is a constellation of malformations which result from the severe underdevelopment of any left-sided cardiac structures. Once considered to be universally fatal, the prognosis for this condition has tremendously improved over the past four decades since the work of William Norwood in the early 1980s. Today, a staged surgical approach is applied for palliating this distinctive cohort of patients, in which they undergo three operative procedures in the first 10 years of their life. Advancements in medical technologies, surgical techniques, and our growing experience in the management of HLHS have made survival into adulthood a possibility. Through this review, we present the different phases of the staged approach with primary focus on stage 1-its modifications, current technique, alternatives, and latest outcomes.

18.
J Racial Ethn Health Disparities ; 8(5): 1161-1167, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-32946070

RESUMO

OBJECTIVES: Investigate whether or not race is associated with differences in hospitalization and survival to discharge among patients with coronavirus disease-2019 (COVID-19) at the height of the pandemic in New York City (NYC). METHODS: Single-center retrospective cohort study of COVID-19 patients hospitalized at our university-affiliated NYC hospital from 3/10/20 through 4/13/20 with follow-up to 5/1/20. Our primary endpoint was hospitalization rate among patients with confirmed COVID-19 compared with the regional population based on race. Our secondary endpoint survival to discharge among hospitalized COVID-19 patients. NYC Department of Health data were used to calculate hospitalization odds ratios. Chi-square and t tests were used to compare categorial and continuous variables, respectively. Cox proportional hazards regression and predictive analysis were used to investigate our endpoints further. RESULTS: Our cohort of 734 patients included 355 women (48.4%), 372 Blacks (50.7%), 214 Whites (29.2%), and 92 Hispanics (12.5%) in our analysis. Blacks were nearly twice as likely as Whites to require hospitalization for COVID-19 (OR 1.89, 95% CI, 1.59-2.24, p < 0.001). Hispanics were also more likely to suffer in-hospital mortality from COVID-19 compared with Whites (HR 1.84; 95% CI 1.21-2.80; p = 0.005). There was a non-significant increased hazard of in-hospital mortality among Blacks when compared with Whites (HR, 1.30; 95% CI, 0.95-1.78; p = 0.09). CONCLUSIONS AND RELEVANCE: Blacks were more likely than Whites to require hospitalization for COVID-19 while Hispanics were more likely to experience in-hospital mortality. Further investigation into the socioeconomic factors underlying racial disparities in COVID-19 survival and severity requiring hospitalization is needed on a national scale.


Assuntos
Negro ou Afro-Americano/estatística & dados numéricos , COVID-19/etnologia , Disparidades nos Níveis de Saúde , Hispânico ou Latino/estatística & dados numéricos , Mortalidade Hospitalar/etnologia , Hospitalização/estatística & dados numéricos , Pandemias , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/mortalidade , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cidade de Nova Iorque/epidemiologia , População Branca/estatística & dados numéricos , Adulto Jovem
19.
J Org Chem ; 86(1): 1108-1117, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33332119

RESUMO

A Rh-catalyzed pot and step economic synthesis of aza-polycyclic aromatic hydrocarbons (N-PAHs) from readily available aryl ketones and alkynes has been disclosed. Additionally, a novel synthetic application of the well-known aminating reagent hydroxylamine-O-sulfonic acid (HOSA) has been explored as an in situ redox-neutral directing group for the formation of N-PAHs via isoquinoline. Multiple bond formation in a single operation through a cascade of triple C-H bond activations is the beauty of this protocol. The challenging annulations of two different alkynes in a regioselective fashion have been demonstrated effectively. Mechanistic studies reveal that 3,4-diphenyl-1-methylisoquinoline is an active intermediate for this one-pot transformation.

20.
J Org Chem ; 86(1): 1074-1083, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33351628

RESUMO

A redox neutral Co(III)-catalyzed annulation of α,ß-unsaturated oxime ether with alkyne has been reported. Multisubstituted pyridines were synthesized in good yields without the use of any heavy metal oxidants. The developed methodology tolerates a variety of functional groups. Notably, this transformation has been applied to the late-stage modification of the bioactive molecule dehydropregnenolone.

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