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1.
Photochem Photobiol ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38597042

RESUMO

In this manuscript, we demonstrate a visible-light driven dimerization of para-quinone methides using eosin Y catalyst via a reductive homocoupling process. This mild and operationally simple methodology was found to be compatible with a variety of differently substituted para-quinone methides and a broad range of tetra-arylethane derivatives were obtained in moderate to good yields (47%-87%).

2.
PLoS One ; 19(3): e0285650, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38451887

RESUMO

College students with more emotional support experience lower levels of anxiety and other psychosocial and behavioral problems. During the COVID-19 pandemic, the emotional well-being of college students was additionally challenged by an abrupt shift to distance learning followed by a return to face-to-face classes. In this exploratory study, we compared the levels of perceived emotional support and anxiety among incoming first-year undergraduate students, prior to starting classes, which included different learning modes in five semesters of instruction from 2021-2023 (three distance semesters and two face-to-face semesters). Data from 8659 undergraduate students were extracted from a Mexican state university database, corresponding to students' responses collected during new student orientation week. Participants were students in the arts and humanities (9.7%), social and legal sciences (38%), life and health sciences (28.9%), and engineering and architecture (23.4%). Anxiety levels were measured with the GAD-7 scale, and emotional support was measured using a subscale of the PERACT-R (To go through with resilience) inventory. Comparisons of emotional support and anxiety scores among semesters revealed highly significant differences with small effect sizes. Anxiety levels increased significantly with mean average of 6.65 SD(5.52) during the baseline measure to the highest in 2022-2 to 7.53 SD(5.3) and Emotional Support decreased systematically each semester from baseline mean = 8.03 SD(2.0) to the lowest 7.52 SD(1.8) in 2022-2. The results show that a return to face-to-face classes was associated with increased anxiety levels, whereas levels of emotional support systematically decreased across the five semesters. MANOVA analysis revealed significant differences in anxiety and emotional support scores between semesters, with peaks during the learning mode semester that students returned to face-to-face classes after distance learning even after adjusting for gender. Given that the effect of emotional support on anxiety may be related to success in future educational and professional activities, it is important to develop interventions to restore and increase college students' emotional support levels and develop anxiety management strategies.


Assuntos
COVID-19 , Pandemias , Humanos , COVID-19/epidemiologia , Ansiedade , Transtornos de Ansiedade , Estudantes
3.
Curr Oncol ; 31(1): 436-446, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38248114

RESUMO

The COVID-19 pandemic precipitated drastic changes in cancer care. Its impact on the U.S. head and neck cancer population has yet to be fully understood. This study aims to understand the impact of pandemic-related changes on the head and neck cancer population. An observational study of head and neck cancer patients at a single institution during the spring of 2020 and 2019 was performed. Clinical characteristics and survival outcomes were analyzed. In 2020, 54 head and neck cancer patients were evaluated in the department of radiation oncology vs. 74 patients seen in 2019; 42% of the patients were female in 2019 versus 24% in 2020 (p = 0.036). The median follow-up time was 19.4 and 31 months for 2020 and 2019, respectively. After adjusting for stage, the relapse-free survival probability at 6 and 12 months was 79% and 69% in 2020 vs. 96% and 89% in 2019, respectively (p = 0.036). There was no significant difference in the overall survival, with 94% and 89% in 2020 and 2019, respectively (p = 0.61). Twenty-one percent of patients received induction chemotherapy in 2020 versus 5% in 2019 (p = 0.011); significantly more treatment incompletions occurred in 2020, 9% vs. 0% in 2019 (p = 0.012). Moreover, the stage-adjusted RFS differed between cohorts, suggesting head and neck cancer patients seen during the initial wave of COVID-19 may experience worse oncologic outcomes.


Assuntos
COVID-19 , Neoplasias de Cabeça e Pescoço , Radioterapia (Especialidade) , Humanos , Feminino , Masculino , COVID-19/epidemiologia , Pandemias , Oncologia , Neoplasias de Cabeça e Pescoço/terapia
4.
PLoS One ; 18(11): e0293605, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37939153

RESUMO

Vancomycin, is widely used against methicillin-resistant bacterial infections. However, Vancomycin accumulation causes nephrotoxicity which leads to an impairment in the filtration mechanisms of kidney. Traditional herbal medicines hold potential for treatment of drug-induced nephrotoxicity. Herein, we investigated protective properties of plant-based medicine Renogrit against Vancomycin-induced kidney injury. Phytometabolite analysis of Renogrit was performed by UHPLC. Spheroids formed from human proximal tubular cell (HK-2) were used for in vitro evaluation of Vancomycin-induced alterations in cell viability, P-gp functionality, NAG, KIM-1 levels, and mRNA expression of NGAL and MMP-7. The in vivo efficacy of Renogrit against Vancomycin-induced nephrotoxicity was further evaluated in Sprague-Dawley (SD) rats by measurement of BUN, serum creatinine, and their respective clearances. Moreover, eGFR, kidney-to-body weight ratio, GSH/GSSG ratio, KIM-1, NAG levels and mRNA expression of KIM-1 and osteopontin were also analyzed. Changes in histopathology of kidney and hematological parameters were also observed. Renogrit treatment led to an increase in cell viability, normalization of P-gp functionality, decrease in levels of NAG, KIM-1, and reduction in mRNA expression of NGAL and MMP-7. In Vancomycin-challenged SD rats, Renogrit treatment normalized altered kidney functions, histological, and hematological parameters. Our findings revealed that Renogrit holds a clinico-therapeutic potential for alleviating Vancomycin-associated nephrotoxicity.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Vancomicina , Ratos , Animais , Humanos , Ratos Sprague-Dawley , Creatinina , Metaloproteinase 7 da Matriz/metabolismo , Lipocalina-2/metabolismo , Nitrogênio da Ureia Sanguínea , Ureia/metabolismo , Rim/patologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , RNA Mensageiro/metabolismo , Biomarcadores
5.
Org Biomol Chem ; 21(30): 6218-6224, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37482765

RESUMO

Herein, we demonstrate a redox-neutral, operationally simple, atom-economical, and additive-free approach for the synthesis of indolyl diarylmethanes via a radical reaction of indoles with para-quinone methides (p-QMs) under visible-light mediated reaction conditions using eosin Y as an organophotoredox catalyst. This protocol was found to be compatible with a wide range of differently substituted p-QMs and indoles in organic as well as in aqueous media under visible-light irradiation, furnishing the desired products in good to excellent yields.

6.
Org Biomol Chem ; 21(24): 5072-5078, 2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37273009

RESUMO

We describe here an acid-mediated one-pot approach to access substituted xanthene and thioxanthane derivatives from ortho-heteroaryl phenyl-substituted para-quinone methides via 1,6 intramolecular arylation. The scope of this work was further elaborated to the synthesis of 10H-indolo[1,2-a]indole-based heterocyclic systems using indole based para-quinone methides.

7.
Biomed Pharmacother ; 163: 114785, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37137183

RESUMO

Obesity has become an unprecedented epidemic worldwide owing to a prolonged imbalance between energy intake and expenditure. Available therapies primarily suppress energy intake but often fail to produce sustained fat loss, necessitating a more efficacious strategy to combat obesity. In this study, a polyherbal formulation, Divya-WeightGo (DWG) has been investigated for its anti-obesity activity using in-vitro and in-vivo assays. Ultra-high performance liquid chromatography (UHPLC) analysis revealed the presence of phytocompounds including gallic acid, methyl gallate, corilagin, ellagic acid, pentagalloyl glucose, withaferin A and hydroxycitric acid, proven to aid in weight loss. The exposure of 3T3-L1 cells to DWG at cytosafe concentrations inhibited lipid and triglyceride accumulation and downregulated the expression of several adipogenic and lipogenic markers like PPARy, C/EBPα, C/EBPß, SREBP-1c, FASN and DGAT1. DWG reduced LPS-induced pro-inflammatory cytokine release and NF-κB activity in THP-1 cells. The in-vivo anti-obesity activity of DWG, both alone and in combination with moderate aerobic exercise, was assessed in a high fat diet-induced obese mouse model. DWG mitigated the obesity associated increased body weight gain, feed efficiency ratio, glucose intolerance, diminished insulin sensitivity, dyslipidemia, altered liver function profile, lipid accumulation and adiposopathy in obese mice, alone as well as in combination intervention, with better efficacy in the combination approach. Thus, the findings of this study suggest that DWG could be a promising therapeutic avenue to treat obesity through attenuation of lipid and fat accumulation in liver and adipose tissues and could be utilized as an adjunct with lifestyle interventions to combat obesity and associated complications.


Assuntos
Fármacos Antiobesidade , Resistência à Insulina , Camundongos , Animais , Camundongos Obesos , Dieta Hiperlipídica/efeitos adversos , Fármacos Antiobesidade/farmacologia , Fármacos Antiobesidade/uso terapêutico , Obesidade/metabolismo , Fígado , Triglicerídeos , Biomarcadores/metabolismo , Camundongos Endogâmicos C57BL , Células 3T3-L1
8.
Org Biomol Chem ; 21(12): 2493-2498, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36880335

RESUMO

A metal-free approach for the synthesis of tetrahydroindolo[2,3-b]carbazoles has been developed through an acid-mediated one-pot [3 + 3]-annulation of 2-indolylmethanols and 3-indolyl-substituted para-quinone methides. This operationally simple protocol allowed us to prepare many unsymmetrical tetrahydroindolo[2,3-b]carbazoles in good to excellent yields with a broad substrate scope. This concept was also elaborated to the synthesis of tetrahydrothieno[2,3-b]carbazoles and tetrahydrothieno[3,2-b]carbazoles.

9.
J Audiol Otol ; 27(2): 63-70, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36791798

RESUMO

BACKGROUND AND OBJECTIVES: Cochlear implantation in late implanted prelinguals necessitates a complex decision-making process for clinicians and patients due to the uncertainty of achieving adequate benefit in auditory and speech perception. This study longitudinally evaluated clinical and social outcomes of prelingually deaf children with implantation in their late childhood. Subjects and. METHODS: A total of 113 (49 females and 64 males) participants, with an age range of 5-15 years, were assessed for the pre-implant parameters such as hearing loss etiology, aided responses, anatomical aspects, and psychological evaluation. The Category of Auditory Performance, Speech Awareness Threshold, Speech Reception Threshold, and Speech Discrimination Score were administered to assess the patient's auditory skills. Further, the Speech Intelligibility Rating scale was administered to evaluate the patient's speech intelligibility at 3, 6, 9, 12, 18, and 24 months post-surgery. Subjectively perceived benefits were evaluated using the satisfaction rating scale and a questionnaire. RESULTS: The statistical results showed a significant impact of cochlear implantation in all domains. Positive impact and improvement post-implantation were noted in all the spheres, including auditory, linguistic, social, and educational. CONCLUSIONS: The study highlighted that the outcomes of a cochlear implant at a later age might not parallel with the implantation at a younger age. However, this still provides measurable benefits even after a longer period of auditory deprivation.

10.
Int J Radiat Oncol Biol Phys ; 116(4): 858-868, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-36690161

RESUMO

PURPOSE: Stereotactic radiosurgery (SRS) and immune checkpoint inhibitors (ICI) are highly effective treatments for brain metastases, particularly when these therapies are administered concurrently. However, there are limited data reporting the risk of radiation necrosis (RN) in this setting. METHODS AND MATERIALS: Patients with brain metastases from primary non-small cell lung cancer, renal cell carcinoma, or melanoma treated with SRS and ICI were considered. Time-to-event analyses were conducted for any grade RN and symptomatic RN (SRN) with death incorporated as a competing risk. As a secondary analysis, recursive partitioning analysis (RPA) was used for model development, and a loop of potential models was analyzed, with the highest-fidelity model selected. Brain V12 Gy thresholds identified on RPA were then incorporated into the competing risks analysis. Concurrent SRS and ICI administration. RESULTS: Six hundred fifty-seven patients with 4182 brain metastases across 11 international institutions were analyzed. The median follow-up for all patients was 13.4 months. The median follow-up was 12.8 months and 14.1 months for the concurrent and nonconcurrent groups, respectively (P = .03). The median patient age was 66 years, and the median Karnofsky Performance Status was 90. In patients with any grade RN, 1- and 2-year rates were 6.4% and 9.9%, respectively. In patients with SRN, 1- and 2-year rates were 4.8% and 7.2%, respectively. On RPA, the highest-fidelity models consistently identified V12 Gy as the dominant variable predictive of RN. Three risk groups were identified by V12 Gy: (1) < 12 cm3; (2) 20 cm3 ≥ V12 Gy ≥ 12 cm3; (3) V12 Gy > 20 cm3. In patients with any grade RN, 1-year rates were 3.7% (V12 Gy < 12 cm3), 10.3% (20 cm3 ≥ V12 Gy ≥ 12 cm3), and 12.6% (V12 Gy > 20 cm3); the 2-year rates were 7.5% (V12 Gy < 12 cm3), 13.8% (20 cm3 ≥ V12 Gy ≥ 12 cm3), and 15.4% (V12 Gy > 20 cm3) (P < 0.001). In patients with any SRN, 1-year rates were 2.4% (V12 Gy < 12 cm3), 8.9% (20 cm3 ≥ V12 Gy ≥ 12 cm3), and 10.3% (V12 Gy > 20 cm3); the 2-year rates were 4.4% (V12 Gy < 12 cm3), 12.4% (20 cm3 ≥ V12 Gy ≥ 12 cm3), and 13.1% (V12 Gy > 20 cm3; P < 0.001). There were no statistically significant differences in rates of any grade RN or SRN when accounting for therapy timing for all patients and by V12 risk group identified on RPA. CONCLUSIONS: The use of SRS and ICI results in a low risk of any grade RN and SRN. This risk is not increased with concurrent administration. Therefore, ICI can safely be administered within 4-weeks of SRS. Three risk groups based on V12 Gy were identified, which clinicians may consider to further reduce rates of RN.


Assuntos
Neoplasias Encefálicas , Carcinoma Pulmonar de Células não Pequenas , Carcinoma de Células Renais , Neoplasias Renais , Neoplasias Pulmonares , Melanoma , Radiocirurgia , Humanos , Idoso , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Inibidores de Checkpoint Imunológico/uso terapêutico , Carcinoma de Células Renais/radioterapia , Radiocirurgia/efeitos adversos , Radiocirurgia/métodos , Neoplasias Pulmonares/cirurgia , Estudos Retrospectivos , Neoplasias Encefálicas/patologia , Melanoma/radioterapia , Neoplasias Renais/cirurgia
11.
Laryngoscope ; 133(5): 1110-1121, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-35716359

RESUMO

OBJECTIVE(S): There has been a disproportionate increase in the incidence of young patients with squamous cell carcinoma of the oral tongue (SCCOT). The purpose of this study was to compare young patients to older patients with SCCOT without prior drinking or smoking history as this population is poorly characterized in the literature. METHODS: A retrospective review of patients presenting to our institution with SCCOT was performed. The clinical and pathologic characteristics, as well as, outcomes were compared between younger patients (age ≤45) and older patients (age >45). Outcome analysis was performed using Kaplan Meier method. Multivariable Cox proportional hazard models were performed for age and stage. RESULTS: Eighty-two patients (38 young, 44 old) were included in this study. Median follow-up was 29.4 months. When compared to the older cohort (age >45), the younger cohort (age ≤45) demonstrated lower rates of 5-year locoregional control (LC) (79.6% vs. 52.5%, p = 0.043) and distant metastasis-free survival (88.1% vs. 61.8%, p = 0.006). Both cohorts demonstrated similar overall survival rates (55.5% vs. 58.1%) and disease-specific survival (66.2% vs. 58.1%). Of patients experiencing locoregional failure with available radiation therapy plans and PET scans in younger cohorts (n = 7), 100% demonstrated in-field failures. Multivariable Cox proportional hazards demonstrated age was an independent predictor of DMFS (p = 0.004) and the advanced stage was a predictor of DSS (p = 0.03). CONCLUSIONS: Young, nondrinker, nonsmokers with SCCOT demonstrate high rates of locoregional recurrence, distant metastasis, and in-field failures. Future studies are warranted to determine underlying mechanisms driving pathogenesis in this unique cohort. LEVEL OF EVIDENCE: 3 Laryngoscope, 133:1110-1121, 2023.


Assuntos
Carcinoma de Células Escamosas , Neoplasias da Língua , Humanos , não Fumantes , Estadiamento de Neoplasias , Recidiva Local de Neoplasia/patologia , Carcinoma de Células Escamosas/patologia , Estudos Retrospectivos , Língua/patologia , Prognóstico
12.
Cancers (Basel) ; 14(11)2022 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-35681789

RESUMO

Thirty percent of patients with head and neck squamous cell carcinoma (HNSCC) are at least 70 years of age. This number continues to rise as life expectancy continues to increase. Still, older adults with HNSCC remain underrepresented in clinical trials, resulting in ambiguity on optimal management. Older adults are a complex patient population, often requiring increased support due to issues relating to functional and performance status, medical comorbidities, and medication management. Furthermore, in older adults with HNSCC, many of these conditions are independently associated with increased toxicity and worse outcomes. Toxicity in the older adult remains difficult to predict and to understand, and as treatment decisions are based on treatment tolerability, it is essential to understand the toxicities and how to minimize them. Novel predictive scores are being developed specifically for older adults with HNSCC to understand toxicity and to assist in personalized treatment decisions. There are clinical trials presently underway that are investigating shortened radiation courses and novel, less toxic systemic treatments in this population. In the forthcoming sections, we provide a detailed overview of the clinical data, treatment paradigms, and considerations in this population. This review provides a comprehensive overview of existing clinical data and clinical considerations in the older adult head and neck cancer population. Additionally, we provide a detailed overview of pertinent current and ongoing clinical trials, as well as future areas for investigation.

14.
J Audiol Otol ; 26(4): 202-207, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35405064

RESUMO

BACKGROUND AND OBJECTIVES: Single-sided deafness (SSD) leads to non-participation of the diseased ear in generating adequate auditory input, which results in poor speech discrimination in noisy surroundings. The present study objectively compared the audiological benefits rendered by contralateral routing of signal (CROS) hearing aid and bone conduction device (BCD) in patients with SSD >70 dB HL using the modified hearing in noise test (HINT). MATERIALS AND METHODS: Patients with SSD >70 dB HL in poor and clinically normal hearing in the better ear were enrolled. Patients aged <18 or >70 years, with a history of neurological insult or ear infection in the last 3 months, mental retardation, psychiatric or developmental disorders, and diabetes were excluded. Modified HINT was performed with the affected ear unaided, aided with CROS hearing aid, and with BCD, generating three groups. Noise signal was presented at a fixed intensity of 65 dB at the neutral position in the center and speech signal was presented to either ear sequentially. The test was repeated with the speech signal fixed at the neutral position and the noise signal presented to either ear. RESULTS: BCD led to a better signal-to-noise ratio (SNR) than CROS hearing aid in all situations except when noise was centralized and speech was presented to the affected ear. CONCLUSIONS: A benefit was observed when auditory rehabilitation was used for the affected ear as demonstrated by better SNR scores. The results showed that BCD performed better than CROS hearing aid.

15.
J Am Coll Radiol ; 19(4): 542-551, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35247326

RESUMO

PURPOSE: Patient experience scores are increasingly important in measuring quality of care and determining reimbursement from payers, including the Hospital Value-Based Purchasing Program and the Radiation Oncology Model. However, the role of bias in patient experience scores in oncology is unknown, raising the possibility that such payment structures may inadvertently perpetuate bias in reimbursement. Therefore, the authors characterized patient-, physician-, and practice-level predictors of patient experience scores in patients undergoing radiation therapy. METHODS: The authors retrospectively reviewed patient experience surveys for radiation oncology patients treated at two large multisite academic cancer centers. The outcome was responses on four survey questions. Covariates included self-reported patient demographics, physician characteristics, practice setting characteristics, and wait-time rating linked to each survey. Multivariable ordinal regression models were fitted to identify predictors of receiving a higher score on each of the survey questions. RESULTS: In total, 2,868 patients completed surveys and were included in the analysis. Patient experience scores were generally high, with >90% of respondents answering 5 of 5 on the four survey items. Physician gender was not associated with any measured patient experience outcomes (P > 0.40 for all). Independent predictors of higher score included a wait-time experience classified as "good" compared with "not good" (q < .001 for all). CONCLUSIONS: Oncology practices aiming to improve patient experience scores may wish to focus their attention on improving wait times for patients. Although a difference in patient experience scores on the basis of physician gender was not observed, such bias is likely to be complex, and further research is needed to characterize its effects.


Assuntos
Radioterapia (Especialidade) , Humanos , Avaliação de Resultados da Assistência ao Paciente , Satisfação do Paciente , Estudos Retrospectivos , Inquéritos e Questionários
16.
Cancer ; 128(7): 1429-1438, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35077586

RESUMO

BACKGROUND: Patients with renal cell carcinoma (RCC) brain metastases are frequently treated with immune checkpoint inhibitors (ICIs) and stereotactic radiosurgery (SRS). However, data reporting on the risk of developing radiation necrosis (RN) are limited. METHODS: RN rates were compared for concurrent therapy (ICI/SRS administration within 4 weeks of one another) and nonconcurrent therapy with the χ2 test. Univariable logistic regression was used to identify factors associated with developing RN. RESULTS: Fifty patients (23 concurrent and 27 nonconcurrent) with 395 brain metastases were analyzed. The median follow-up was 12.1 months; the median age was 65 years. The median margin dose was 20 Gy, and 4% underwent prior whole-brain radiation therapy (WBRT). The median treated tumor volume was 3.32 cm3 (range, 0.06-42.38 cm3 ); the median volume of normal brain tissue receiving a dose of 12 Gy or higher (V12 Gy) was 8.42 cm3 (range, 0.27-111.22 cm3 ). Any-grade RN occurred in 17.4% and 22.2% in the concurrent and nonconcurrent groups, respectively (P = .67). Symptomatic RN occurred in 4.3% and 14.8% in the concurrent and nonconcurrent groups, respectively (P = .23). Increased tumor volume during SRS (odds ratio [OR], 1.08; 95% confidence interval [CI], 1.01-1.19; P = .04) was associated with developing RN, although V12 Gy (OR, 1.03; 95% CI, 0.99-1.06; P = .06), concurrent therapy (OR, 0.74; 95% CI, 0.17-2.30; P = .76), prior WBRT, and ICI agents were not statistically significant. CONCLUSIONS: Symptomatic RN occurs in a minority of patients with RCC brain metastases treated with ICI/SRS. The majority of events were grade 1 to 3 and were managed medically. Concurrent ICI/SRS does not appear to increase this risk. Attempts to improve dose conformality (reduce V12) may be the most successful mitigation strategy in single-fraction SRS.


Assuntos
Neoplasias Encefálicas , Carcinoma de Células Renais , Neoplasias Renais , Radiocirurgia , Idoso , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundário , Carcinoma de Células Renais/radioterapia , Irradiação Craniana , Humanos , Neoplasias Renais/etiologia , Neoplasias Renais/radioterapia , Necrose/etiologia , Radiocirurgia/efeitos adversos , Estudos Retrospectivos
17.
ACS Org Inorg Au ; 2(2): 186-196, 2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-36855457

RESUMO

Carbocation catalysis is emerging as an important subarea of Lewis acid catalysis. Some stable and isolable carbocations have been successfully utilized as Lewis acid catalysts and promoters in many synthetic transformations. In this manuscript, we report a tropylium cation-promoted vinylogous aza-Michael addition of carbamates to para-quinone methides (QMs) to access a wide range of unsymmetrical α,α'-diarylmethyl carbamates. This mild protocol was effective for the vinylogous conjugate addition of (-)-menthyl carbamate to p-QMs, and the respective diastereomerically pure α,α'-diarylmethyl carbamate derivatives could be obtained in excellent yields and diastereoselectivities (up to >20:1 de).

18.
Concurr Comput ; 34(28): e7390, 2022 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-36718458

RESUMO

The coronavirus (COVID-19) started in China in 2019, has spread rapidly in every single country and has spread in millions of cases worldwide. This paper presents a proposed approach that involves identifying the relative impact of COVID-19 on a specific gender, the mortality rate in specific age, investigating different safety measures adopted by each country and their impact on the virus growth rate. Our study proposes data-driven analysis and prediction modeling by investigating three aspects of the pandemic (gender of patients, global growth rate, and social distancing). Several machine learning and ensemble models have been used and compared to obtain the best accuracy. Experiments have been demonstrated on three large public datasets. The motivation of this study is to propose an analytical machine learning based model to explore three significant aspects of COVID-19 pandemic as gender, global growth rate, and social distancing. The proposed analytical model includes classic classifiers, distinctive ensemble methods such as bagging, feature based ensemble, voting and stacking. The results show a superior prediction performance comparing with the related approaches.

19.
Br J Neurosurg ; 36(1): 79-85, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32538686

RESUMO

OBJECT: The authors performed an extensive comparison between patients treated with open versus an endoscopic approach for skull base malignancy with emphasis on surgical outcomes. METHODS: A single-institution retrospective review of 60 patients who underwent surgery for skull base malignancy between 2009 and 2018 was performed. Disease features, surgical resection, post-operative morbidities, adjuvant treatment, recurrence, and survival rates were compared between 30 patients who received purely open surgery and 30 patients who underwent purely endoscopic resection for a skull base malignancy. RESULTS: Of the 60 patients with skull base malignancy, 30 underwent open resection and 30 underwent endoscopic resection. The most common hisotype for endoscopic resection was squamous cell carcinoma (26.7%), olfactory neuroblastoma (16.7%), and sarcoma (10.0%), and 43.3%, 13.3%, and 10.0% for the open resection cohort, respectively. There were no statistical differences in gross total resection, surgical-associated cranial neuropathy, or ability to achieve negative margins between the groups (p > 0.1, all comparisons). Patients who underwent endoscopic resection had shorter surgeries (320.3 ± 158.5 minutes vs. 495.3 ± 187.6 minutes (p = 0.0003), less intraoperative blood loss (282.2 ± 333.6 ml vs. 696.7 ± 500.2 ml (p < 0.0001), and shorter length of stay (3.5 ± 3.7 days vs. 8.8 ± 6.0 days (p < 0.0001). Additionally, patients treated endoscopically initiated adjuvant radiation treatment more quickly (48.0 ± 20.3 days vs. 72.0 ± 20.5 days (p = 0.01). CONCLUSIONS: An endoscopic endonasal approach facilitates a clinically meaningful improvement in surgical outcomes for skull base malignancies.


Assuntos
Neoplasias Nasais , Neoplasias da Base do Crânio , Endoscopia , Humanos , Cavidade Nasal/cirurgia , Neoplasias Nasais/cirurgia , Estudos Retrospectivos , Base do Crânio/cirurgia , Neoplasias da Base do Crânio/patologia , Neoplasias da Base do Crânio/cirurgia , Resultado do Tratamento
20.
Cureus ; 13(7): e16310, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34405069

RESUMO

Objectives Chemoradiation therapy (CRT) has been established as a standard treatment for locally advanced hypopharynx/larynx squamous cell carcinoma (SCC) but the role of induction chemotherapy (IC) remains unclear. The primary outcome of this study is to determine whether functional larynx-preservation survival (FLPS) is improved with the addition of IC in these patients. Secondary outcomes were overall survival (OS), progression-free survival (PFS), distant metastasis-free survival (DMFS), and laryngectomy rates. Methods Records for patients with AJCC 8th edition clinical stage III-IVB laryngeal and hypopharyngeal SCC treated with CRT +/- IC from 2005-2019 were reviewed. FLPS was defined as time until death, progression, laryngectomy, or non-functional larynx. Kaplan-Meier curves were generated for FLPS, OS, PFS, and DMFS. Outcomes were compared using the stratified log-rank test. Laryngectomy rates were compared using Fisher's exact test. Results We included 52 patients with laryngeal and 38 with hypopharyngeal SCC (n=90); 19 patients with laryngeal SCC and 19 with hypopharyngeal SCC received IC (median three cycles). There were no differences in the three-year FLPS (61% vs 67.8%; p=0.88), OS (73.9% vs 86.2%; p=0.42), PFS (53.6% vs 62.6%; p=0.44), or DMFS (65.2% vs 71.5%, p= 0.85) between patients who did and did not receive IC all patients. Laryngectomy rates did not differ with and without IC (18.4 % vs 7.7%; p=0.19). Conclusion In this study of advanced laryngeal and hypopharyngeal SCC, IC did not improve three-year FLPS, OS, PFS, or laryngectomy rates compared to CRT alone. A large prospective series would provide a more robust understanding of the role of IC in this group of patients.

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