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1.
Langmuir ; 40(25): 13010-13016, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38858173

RESUMO

Soft conductive materials are of interest for a wide range of applications, but their syntheses have remained difficult. Herein, we present a convenient route for underwater fabrication of a composite made of carbon nanotubes (CNTs) and mussel-inspired complex coacervates. The key to success of this method is that CNTs were solubilized very effectively in protocoacervates, which are high-concentration solutions of polyelectrolytes at a pH where only one of them is charged, thereby impeding coacervate formation. Composite materials were formed by the simple injection of CNT-dispersed protocoacervate solutions into water under ambient conditions. The method is simple, fast, and ecofriendly, and composites of CNT-complex coacervate in the form of films or bulk materials were obtained. The composites demonstrated electrical conductivity and tunable mechanical properties, which depended on the concentration of polyelectrolytes and the CNT:protocoacervate ratio. Hence, the composites can be manipulated to attain diverse properties, for examples, tunable reduced modulus (15 to 32 GPa) and hardness (0.3 to 0.7 GPa) as well as an electrical conductivity of up to 4 × 103 S m-1.

2.
Glob Health Sci Pract ; 12(3)2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38936961

RESUMO

Countries that are high burden for TB must reverse the COVID-19 pandemic's devastating effects to accelerate progress toward ending TB. Vietnam's Double X (2X) strategy uses chest radiography (CXR) and GeneXpert (Xpert) rapid diagnostic testing to improve early detection of TB disease. Household contacts and vulnerable populations (e.g., individuals aged 60 years and older, smokers, diabetics, those with alcohol use disorders, and those previously treated for TB) with and without TB symptoms were screened in community campaigns using CXRs, followed by Xpert for those with a positive screen. In public non-TB district facilities, diabetics, respiratory outpatients, inpatients with lung disease, and other vulnerable populations underwent 2X evaluation. During COVID-19 restrictions in Vietnam, the 2X strategy improved access to TB services by decentralization to commune health stations, the lowest level of the health system, and enabling self-screening using a quick response mobile application. The number needed to screen (NNS) with CXRs to diagnose 1 person with TB disease was calculated for all 2X models and showed the highest yield among self-screeners (11 NNS with CXR), high yield for vulnerable populations in communities (60 NNS) and facilities (19 NNS), and moderately high yield for household contacts in community campaigns (154 NNS). Computer-aided diagnosis for CXRs was incorporated into community and facility implementation and improved physicians' CXR interpretations and Xpert referral decisions. Integration of TB infection and TB disease evaluation increased eligibility for TB preventive treatment among household contacts, a major challenge during implementation. The 2X strategy increased the rational use of Xpert, employing a health system-wide approach that reached vulnerable populations with and without TB symptoms in communities and facilities for early detection of TB disease. This strategy was effectively adapted to different levels of the health system during COVID-19 restrictions and contributed to post-pandemic TB recovery in Vietnam.


Assuntos
COVID-19 , Humanos , Vietnã/epidemiologia , COVID-19/epidemiologia , COVID-19/prevenção & controle , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/prevenção & controle , Tuberculose Pulmonar/epidemiologia , Programas de Rastreamento/organização & administração , Programas de Rastreamento/métodos , SARS-CoV-2 , Pessoa de Meia-Idade , Radiografia Torácica , Tuberculose/diagnóstico , Tuberculose/prevenção & controle , Tuberculose/epidemiologia , Feminino , Pandemias , Masculino , Populações Vulneráveis
3.
Artigo em Inglês | MEDLINE | ID: mdl-38606649

RESUMO

The COVID-19 pandemic has had a negative impact on the mental health of healthcare workers participating in the prevention and control of the pandemic, thereby reducing their quality of life and affecting the quality of patient outcomes. This study aims to explore and deeply understand the mental health problems among healthcare workers participating in the prevention and control of COVID-19 in Ho Chi Minh City, Vietnam. A mixed methods study was undertaken with a descriptive cross-sectional survey of 2870 healthcare workers who have been participating in the prevention and control of COVID-19 in Ho Chi Minh City in 2021, followed by a qualitative descriptive phenomenological study comprised of in-depth interviews with a purposively sampled subset of 40 healthcare workers. Results showed that of the 2870 survey participants, the majority (60.6%) were female, and the average age was 35.1 (SD = 8.6). The prevalence of stress, anxiety and depression was 17.2%, 20.8%, and 17.6%, respectively. The findings from in-depth interviews revealed that the participants were under extreme mental health issues such as worries, stress, and negative emotions. The worrying was related to risk of infection, being shunned, stigmatised, or assaulted by the community. Stress was due to excessive pressure from work. Negative emotions were identified as sadness, self-pity, feelings of loneliness, entrusting fate, feelings of guilt, anxiety, confusion, obsession, disorientation, physical and mental exhaustion. Promoting mental health among healthcare workers who participated in the crisis is necessary and urgent.

4.
Heliyon ; 10(7): e28949, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38617934

RESUMO

Background: Prostate cancer (PCa) and benign prostatic hyperplasia (BPH) are prevalent conditions affecting a significant portion of the male population, particularly with advancing age. Traditional diagnostic methods, such as digital rectal examination (DRE) and prostate-specific antigen (PSA) tests, have limitations in specificity and sensitivity, leading to potential overdiagnosis and unnecessary biopsies. Significance: This study explores the effectiveness of 1H NMR urine metabolomics in distinguishing PCa from BPH and in differentiating various PCa grades, presenting a non-invasive diagnostic alternative with the potential to enhance early detection and patient-specific treatment strategies. Results: The study demonstrated the capability of 1H NMR urine metabolomics in detecting distinct metabolic profiles between PCa and BPH, as well as among different Gleason grade groups. Notably, this method surpassed the PSA test in distinguishing PCa from BPH. Untargeted metabolomics analysis also revealed several metabolites with varying relative concentrations between PCa and BPH cases, suggesting potential biomarkers for these conditions.

5.
J Org Chem ; 89(5): 3202-3210, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38329896

RESUMO

We report a method for using elemental sulfur to facilitate the cyclization of aryl hydrazones and aryl isothiocyanates, affording biorelated 2-imino-1,3,4-thiadiazoles. Reactions progressed in the presence of elemental sulfur, N-methylmorpholine base, and DMSO solvent, while were tolerant of a wide range of functionalities including halogen, nitro, cyano, methylsulfonyl, and heterocyclic groups. The method appears to offer a general pathway for using simple, cheap, and stable reagents to afford triaryl-substituted 2-imino-1,3,4-thiadiazoles under relatively mild conditions.

6.
Sensors (Basel) ; 24(3)2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38339488

RESUMO

The detection of smoky diesel vehicles is a key step in reducing air pollution from transportation. We propose a new method for identifying smoky vehicles that proceeds in three stages: (1) the detection of vehicle shapes, license plates, and smoke regions; (2) the implementation of the two matching techniques based on the smoke region-vehicle shape and smoke region-license plate relationships; and (3) the refinement of the smoke region detected. The first stage involves the evaluation of various You Only Look Once (YOLO) models to identify the best-fit model for object detection. YOLOv5s was the most effective, particularly for the smoke region prediction, achieving a precision of 91.4% and a mean average precision at 0.5 (mAP@0.5) of 91%. It also had the highest mean mAP@0.5 of 93.9% across all three classes. The application of the two matching techniques significantly reduced the rate of false negatives and enhanced the rate of true positives for the smoky diesel vehicles through the detection of their license plates. Moreover, a refinement process based on image processing theory was implemented, effectively eliminating incorrect smoke region predictions caused by vehicle shadows. As a result, our method achieved a detection rate of 97.45% and a precision of 93.50%, which are higher than that of the two existing popular methods, and produced an acceptable false alarm rate of 5.44%. Particularly, the proposed method substantially reduced the processing time to as low as 85 ms per image, compared to 140.3 and 182.6 ms per image in the two reference studies. In conclusion, the proposed method showed remarkable improvements in the accuracy, robustness, and feasibility of smoky diesel vehicle detection. Therefore, it offers potential to be applied in real-world situations.

7.
Data Brief ; 52: 110004, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38235183

RESUMO

Adjuvant radiotherapy for breast cancer may involve some incidental exposure of the ipsilateral internal mammary artery to ionizing radiation. However, the relevant evidence is limited and inconsistent. The dataset presented in this article contains the information used to assess the effects of accidental radiation exposure on the internal mammary artery in patients with unilateral total mastectomy followed radiotherapy for breast cancer. The study population consists of two groups: the irradiated group and the control group. The left and right internal mammary arteries were assessed through the second intercostal spaces using a computed sonography system (Vivid S6; GE, Tirat Carmel, Israel) equipped with a 5.5 - 11 MHz transducer. The recorded parameters were the diameter, time-averaged maximum velocity, and blood flow of the internal mammary artery. The dataset contains two files of data: a raw and an analyzed data. The raw data file contains the individual information of each participant, including demographic characteristics and the parameters of the internal mammary artery duplex ultrasound imaging. The analyzed data file was made up of R Markdown, a markup language of R. The results of data analysis were presented in the related research article which has been accepted for publication in the Annals of Vascular Surgery. The dataset presented in this article may be reused for further studies in which the internal mammary artery is considered as potential donor or recipient vessels for a vascular bypass or free flap anastomosis.

8.
Ann Vasc Surg ; 100: 15-24, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38110082

RESUMO

BACKGROUND: The effects of incidental radiation exposure on internal mammary arteries remain unclear. The present study was designed to test the hypothesis by comparing diameter and blood flow of the irradiated and nonirradiated internal mammary arteries, using Duplex ultrasound imaging. METHODS: The study was designed as a single-center, transversal, comparative study. The main outcomes were diameter and volumetric blood flow of the internal mammary arteries. The Wilcoxon rank-sum test was used to assess the differences between the irradiated and nonirradiated internal mammary arteries with regard to the diameter and volumetric blood flow. RESULTS: The diameter (median [interquartile range]) of the irradiated internal mammary arteries (0.170 mm [0.160, 0.180]) was smaller than that of the contralateral nonirradiated ones (0.180 mm [0.170, 0.200], P < 0.0001) and that of the internal mammary arteries in the control group (0.180 mm [0.170, 0.190], P < 0.0001). Similarly, blood flow (median [interquartile range]) of the irradiated internal mammary arteries (52.4 ml/min [37.78, 65.57]) was smaller than that of the contralateral nonirradiated ones (62.7 ml/min [46.87, 84.17], P < 0.0001), as well as of the left (56.7 ml/min [46.88, 72.58], P = 0.02) and the right internal mammary arteries in the control group (61.0 ml/min [47.47, 74.52], P = 0 0.0009). CONCLUSIONS: The data indicate that the irradiated internal mammary arteries in patients with a history of total mastectomy followed by radiotherapy for breast cancer had significantly smaller diameter and blood flow compared to the nonirradiated internal mammary arteries.


Assuntos
Neoplasias da Mama , Artéria Torácica Interna , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Artéria Torácica Interna/diagnóstico por imagem , Mastectomia Simples , Mastectomia , Resultado do Tratamento
9.
Nat Med ; 29(10): 2547-2558, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37696935

RESUMO

Inducing antiretroviral therapy (ART)-free virological control is a critical step toward a human immunodeficiency virus type 1 (HIV-1) cure. In this phase 2a, placebo-controlled, double-blinded trial, 43 people (85% males) with HIV-1 on ART were randomized to (1) placebo/placebo, (2) lefitolimod (TLR9 agonist)/placebo, (3) placebo/broadly neutralizing anti-HIV-1 antibodies (bNAbs) or (4) lefitolimod/bNAb. ART interruption (ATI) started at week 3. Lefitolimod was administered once weekly for the first 8 weeks, and bNAbs were administered twice, 1 d before and 3 weeks after ATI. The primary endpoint was time to loss of virologic control after ATI. The median delay in time to loss of virologic control compared to the placebo/placebo group was 0.5 weeks (P = 0.49), 12.5 weeks (P = 0.003) and 9.5 weeks (P = 0.004) in the lefitolimod/placebo, placebo/bNAb and lefitolimod/bNAb groups, respectively. Among secondary endpoints, viral doubling time was slower for bNAb groups compared to non-bNAb groups, and the interventions were overall safe. We observed no added benefit of lefitolimod. Despite subtherapeutic plasma bNAb levels, 36% (4/11) in the placebo/bNAb group compared to 0% (0/10) in the placebo/placebo group maintained virologic control after the 25-week ATI. Although immunotherapy with lefitolimod did not lead to ART-free HIV-1 control, bNAbs may be important components in future HIV-1 curative strategies. ClinicalTrials.gov identifier: NCT03837756 .


Assuntos
Infecções por HIV , HIV-1 , Receptor Toll-Like 9 , Feminino , Humanos , Masculino , Adjuvantes Imunológicos , Anticorpos Neutralizantes , Anticorpos Amplamente Neutralizantes/uso terapêutico , Anticorpos Anti-HIV/uso terapêutico , Receptor Toll-Like 9/antagonistas & inibidores , Receptor Toll-Like 9/imunologia
10.
Sci Total Environ ; 904: 166021, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37543323

RESUMO

In recent years, the COVID-19 pandemic is currently wreaking havoc on the planet. SARS-CoV-2, the Severe Acute Respiratory Syndrome Coronavirus, is the current term for this outbreak. Reports about this novel coronavirus have been presented since the pandemic's breakout, and they have demonstrated that it transmits rapidly from person to person, primarily by droplets in the air. Findings have illustrated that SARS-CoV-2 can survive on surfaces from hours to days. Therefore, it is essential to find practical solutions to reduce the virus's impact on human health and the environment. This work evaluated common sterilization methods that can decontaminate the environment and items. The goal is that healthcare facilities, disease prevention organizations, and local communities can overcome the new challenge of finding eco-friendly solutions. Further, a foundation of information encompassing various sterilization procedures and highlighting their limits to choose the most appropriate method to stop disease-causing viruses in the new context has been presented. The findings of this crucial investigation contribute to gaining insight into the comprehensive sterilization approaches against the coronavirus for human health protection and sustainable environmental development.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/prevenção & controle , Pandemias/prevenção & controle , Descontaminação/métodos , Esterilização
11.
EMBO Rep ; 24(9): e55376, 2023 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-37503678

RESUMO

Bacteria of the genus Brucella cause brucellosis, one of the world's most common zoonotic diseases. A major contributor to Brucella's virulence is the ability to circumvent host immune defense mechanisms. Here, we find that the DNA-binding protein Dps from Brucella is secreted within the macrophage cytosol, modulating host iron homeostasis and mediating intracellular growth of Brucella. In addition to dampening iron-dependent production of reactive oxygen species (ROS), a key immune effector required for immediate bacterial clearance, cytosolic Dps mediates ferritinophagy activation to elevate intracellular free-iron levels, thereby promoting Brucella growth and inducing host cell necrosis. Inactivation of the ferritinophagy pathway by Ncoa4 gene knockout significantly inhibits intracellular growth of Brucella and host cell death. Our study uncovers an unconventional role of bacterial Dps, identifying a crucial virulence mechanism used by Brucella to adapt to the harsh environment inside macrophages.


Assuntos
Brucella , Brucelose , Humanos , Brucelose/metabolismo , Brucelose/microbiologia , Macrófagos/metabolismo , Morte Celular , Ferro/metabolismo
12.
RSC Adv ; 13(26): 18156-18159, 2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37333726

RESUMO

A method for the annulation of 2-nitrophenols with aryl isothiocyanates is reported. The reactions proceeded in the presence of an iron(iii) acetylacetonate catalyst, elemental sulfur, NaOH as a base, and DMSO as a solvent. Derivatives of 2-aminobenzoxazoles bearing nitro, cyano, acetyl, sulfone, secondary amine, and pyrrolyl groups were successfully isolated.

13.
Chempluschem ; 88(2): e202200426, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36700359

RESUMO

Originating from the concept of classical chemical gardens, a new field coined 'chemobrionics' has recently emerged. In the present work, two chemobrionic systems grown from a hydrogel/liquid interface at different time scales (for 1, 7, 14 or 28 days) were investigated, i. e., a calcium-based hydrogel with a phosphate counterion solution (Ca-gel) and a phosphate-based hydrogel with a calcium counterion solution (P-gel). The initial pH changes of the systems were investigated, and the obtained tubular structures were studied using optical microscopy, SEM, AFM, PXRD and TGA. One of the important findings is that the tubes obtained in the Ca-gel system were straight and long, which could be explained by the larger pH difference observed between the hydrogel and the counterion solution in this system (ΔpH∼2.1) compared to the P-gel system (ΔpH∼0). The Ca-gel structures remained overall more amorphous even though increased crystallinity was observed in both systems with increased time spent in counterion solution. Both systems contained hydroxyapatite phases, with additional calcite phases observed for the P-gel structures and traces of κ-carrageenan for the Ca-gel structures. Our study provides a promising method for controlling tubular macrostructures through adjusting the reaction conditions such as maturation time and pH.

14.
Biosens Bioelectron ; 219: 114810, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36272349

RESUMO

Electronic tongues (e-tongues) have been broadly employed in monitoring the quality of food, beverage, cosmetics, and pharmaceutical products, and in diagnosis of diseases, as the e-tongues can discriminate samples of high complexity, reduce interference of the matrix, offer rapid response. Compared to other analytical approaches using expensive and complex instrumentation as well as required sample preparation, the e-tongue is non-destructive, miniaturizable and on-site method with little or no preparation of samples. Even though e-tongues are successfully commercialized, their application in cancer diagnosis from urine samples is underestimated. In this review, we would like to highlight the various analytical techniques such as Raman spectroscopy, infrared spectroscopy, fluorescence spectroscopy, and electrochemical methods (potentiometry and voltammetry) used as e-tongues for urine analysis towards non-invasive cancer diagnosis. Besides, different machine learning approaches, for instance, supervised and unsupervised learning algorithms are introduced to analyze extracted chemical data. Finally, capabilities of e-tongues in distinguishing between patients diagnosed with cancer and healthy controls are highlighted.

16.
Anal Chem ; 94(51): 17819-17826, 2022 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-36512513

RESUMO

Dengue fever is a global mosquito-borne viral infectious disease that has, in recent years, rapidly spread to almost all regions of the world. Lack of vaccination and directed treatment makes detection at the infection's early stages extremely important for disease prevention and clinical care. In this paper, we developed a rapid and highly sensitive dengue detection tool using a novel platform of diagnosis, called spin-enhanced lateral flow immunoassay (SELFIA) with a fluorescent nanodiamond (FND) as a reporter. Taking advantage of the unique magneto-optical properties of negatively charged nitrogen-vacancy centers in the FND, the SELFIA platform utilizes alternating electromagnetic fields to modulate signals from FND's fluorescence to provide sensitive and specific results. With sandwich SELFIA, we could efficiently detect all four dengue non-structural protein (NS1) serotypes (DV1, DV2, DV3, and DV4). The lowest detection concentration of the dengue NS1 antigens varied from 0.1 to 1.3 ng/mL, which is among the lowest limits of detection to date. The FND-based SELFIA technique is up to 500 and 5000 times more sensitive than carbon black and conventional gold nanoparticles, respectively. By using different anti-NS1 antibodies, we could differentiate the NS1 antigen serotypes contained in the tested samples via three simultaneous assays. Proposed SELFIA allows for both qualitative and quantitative differentiation between different NS1 protein serotypes, which will assist in the development of a highly sensitive and specific detection platform for dengue screening that has the potential to detect the disease at its early stages, especially in high-risk and limited-resource areas.


Assuntos
Vírus da Dengue , Dengue , Nanopartículas Metálicas , Animais , Humanos , Sorogrupo , Ouro , Proteínas não Estruturais Virais , Imunoensaio/métodos , Anticorpos Antivirais , Dengue/diagnóstico , Sensibilidade e Especificidade , Ensaio de Imunoadsorção Enzimática/métodos
17.
Vet World ; 15(9): 2302-2308, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36341051

RESUMO

Background and Aim: Probiotic species have been proven to be beneficial on broiler performance; however, most studies have focused on industrial chickens with fast growth, whereas little information concerning the use of these species on native chickens is available. This study aimed to investigate the effects of probiotics Lactobacillus plantarum (LP) and Bacillus subtilis (BS) on the mortality, growth rate, and carcass characteristics in native Noi chickens challenged with Salmonella Typhimurium. Materials and Methods: We divided 420 1-day-old Noi chicks into seven different treatment groups (n = 60): negative control (no S. Typhimurium, no probiotics or antibiotics); positive control (PC, S. Typhimurium infection, no probiotics or antibiotics); and S. Typhimurium infection and supplementation with LP, BS, LP + BS, enrofloxacin, and commercial probiotics, respectively. Treatment was for 96 days, and the chicks were orally challenged with S. Typhimurium at 22 days old. Results: No deaths occurred during the 4 weeks post-infection in the negative control, LP, or LP+BS groups. The PC group had the highest mortality rate (20%). Re-isolation of S. Typhimurium from the liver, spleen, and heart showed reduced bacterial counts at 1 week post-infection in the LP, BS, and LP + BS groups. The lowest body weight gain was observed in the PC group (949 g/bird), and chicks in the LP group gained 1148 g/bird. An improved feed conversion ratio was noted in the groups receiving probiotic supplementation (3.42-3.50 kg feed/kg gain). There was little evidence that probiotics affected carcass percentage and related parameters, such as breast, thigh and drumstick, and wings. Conclusion: Lactobacillus plantarum or BS dietary supplementation to native Noi broilers resulted in a lower mortality rate and improved body weight gain but did not affect carcass characteristics.

18.
Adv Sci (Weinh) ; 9(34): e2203693, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36266981

RESUMO

The design and characterization of spatiotemporal nano-/micro-structural arrangement that enable real-time and wide-spectrum molecular analysis is reported and demonestrated in new horizons of biomedical applications, such as wearable-spectrometry, ultra-fast and onsite biopsy-decision-making for intraoperative surgical oncology, chiral-drug identification, etc. The spatiotemporal sesning arrangement is achieved by scalable, binder-free, functionalized hybrid spin-sensitive (<↑| or <↓|) graphene-ink printed sensing layers on free-standing films made of porous, fibrous, and naturally helical cellulose networks in hierarchically stacked geometrical configuration (HSGC). The HSGC operates according to a time-space-resolved architecture that modulate the mass-transfer rate for separation, eluation and detection of each individual compound within a mixture of the like, hereby providing a mass spectrogram. The HSGC could be used for a wide range of applictions, including fast and real-time spectrogram generator of volatile organic compounds during liquid-biopsy, without the need of any immunochemistry-staining and complex power-hungry cryogenic machines; and wearable spectrometry that provide spectral signature of molecular profiles emiited from skin in the course of various dietry conditions.


Assuntos
Imunoquímica , Análise Espectral
19.
Anal Chim Acta ; 1221: 340114, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35934355

RESUMO

Electronic tongues (e-tongues) are analytical technologies that mimic the biological tongues which are non-specific, low-selective, and cross-sensitive taste systems. The e-tongues consist of an array of sensors, being able to produce electrical signals that correspond to particular chemical compositions of a sample solution. The performance and efficiency of e-tongues have been optimized for many years via the development of novel materials and technologies. Various conjugated polymers (CPs) have been used in e-tongues over the past decades thanks to their fascinating electrical properties and wide-ranging chemistries. In most studies, CPs such as polypyrrole (PPy), polyaniline (PANI), polythiophene (PT), and poly(3,4-ethylenedioxythiophene) (PEDOT), have drawn considerable interest in e-tongues because of their controllable electrical properties, relatively facile and cost-effective preparation, and good environmental stability that can significantly enhance their versatility, compared to other types of e-tongues. This review article reports major conjugated polymer-based e-tongues (CPETs) that have been studied with these aforementioned CPs over the last two decades.


Assuntos
Polímeros , Pirróis , Nariz Eletrônico , Polímeros/química , Pirróis/química
20.
Chemistry ; 28(52): e202201368, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-35700088

RESUMO

Herein, a SnCl4 -catalyzed intramolecular, interrupted homo-Nazarov cascade biscyclization to access angular (hetero)aryl-fused polycycles is reported. Subsequent decarboxylation of the readily enolizable products afforded the angular products in up to 71 % yield over two steps, with the trans-diastereomers as the major products. The cyclopropyl homo-Nazarov cyclization precursors were formed using a scalable and modular synthetic route that, ultimately, offers access to 6,6,6-, 6,6,5-, 6,5,6-, 6,6,5,6-, and 6,6,6,5-fused angular polycyclic products. To showcase the rigor and utility of the method, an 8-step total synthesis of (±)-1-oxoferruginol, an antibacterial aromatic abietane diterpenoid, was disclosed.


Assuntos
Abietanos , Antibacterianos , Catálise , Ciclização
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