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1.
Funct Integr Genomics ; 24(2): 41, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38386088

RESUMO

Plant diseases pose a severe threat to the food security of the global human population. One such disease is Fusarium wilt, which affects many plant species and causes up to 100% yield losses. Fusarium pathogen has high variability in its genetic constitution; therefore, it has evolved into different physiological races to infect different plant species spread across the different geographical regions of the world. The pathogen mainly affects plant roots, leading to colonizing and blocking vascular bundle cells, specifically xylem vessels. This blocking results in chlorosis, vascular discoloration, leaf wilting, shortening of plant, and, in severe cases, premature plant death. Due to the soil-borne nature of the wilt pathogen, neither agronomic nor plant protection measures effectively reduce the incidence of the disease. Therefore, the most cost-effective management strategy for Fusarium wilt is developing varieties resistant to a particular race of the fungus wilt prevalent in a given region. This strategy requires understanding the pathogen, its disease cycle, and epidemiology with climate-changing scenarios. Hence, in the review, we will discuss the pathogenic aspect and genetics of the Fusarium wilt, including molecular interventions for developing climate-smart wilt tolerant/resistant varieties of crops. Overall, this review will add to our knowledge for advancing the breeding of resistance against the wilt pandemic.


Assuntos
Fusarium , Pandemias , Humanos , Melhoramento Vegetal , Agricultura , Mudança Climática
2.
Small ; : e2403156, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38874058

RESUMO

Energy-efficient glass windows are pivotal in modern infrastructure striving toward the "Zero energy" concept. Electrochromic (EC) energy storage devices emerge as a promising alternative to conventional glass, yet their widespread commercialization is impeded by high costs and dependence on external power sources. Addressing this, redox potential-based self-powered electrochromic (RP-SPEC) devices are introduced leveraging established EC materials like tungsten oxide (WO3) and vanadium-doped nickel oxide (V-NiO) along with aluminum (Al) as an anode. These devices produce open circuit voltages (OCV) exceeding ±0.3 V, enabling autonomous operation for multiple cycles. The WO3 film exhibits 1% transmission and 88% modulation in the colored state at 550 nm with a mere 260 nm thickness. The redox interactions facilitate coloring and bleaching cycles without external power, while photo-charging rejuvenates the system. Notably, the inherent voltages of the RP-SPEC device offer dual functionality, powering electronic devices for up to 81 h. Large-area (≈28 cm2) device feasibility is demonstrated, paving the way for industrial adoption. The RP-SPEC device promises to revolutionize smart window technology by offering both energy efficiency and autonomous operation, thus advancing sustainable infrastructure.

3.
FEMS Yeast Res ; 242024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38444195

RESUMO

In this study, we explored the sphingolipid (SL) landscape in Candida auris, which plays pivotal roles in fungal biology and drug susceptibility. The composition of SLs exhibited substantial variations at both the SL class and molecular species levels among clade isolates. Utilizing principal component analysis, we successfully differentiated the five clades based on their SL class composition. While phytoceramide (PCer) was uniformly the most abundant SL class in all the isolates, other classes showed significant variations. These variations were not limited to SL class level only as the proportion of different molecular species containing variable number of carbons in fatty acid chains also differed between the isolates. Also a comparative analysis revealed abundance of ceramides and glucosylceramides in fluconazole susceptible isolates. Furthermore, by comparing drug-resistant and susceptible isolates within clade IV, we uncovered significant intraclade differences in key SL classes such as high PCer and low long chain base (LCB) content in resistant strains, underscoring the impact of SL heterogeneity on drug resistance development in C. auris. These findings shed light on the multifaceted interplay between genomic diversity, SLs, and drug resistance in this emerging fungal pathogen.


Assuntos
Antifúngicos , Candida , Antifúngicos/farmacologia , Candida auris , Esfingolipídeos , Farmacorresistência Fúngica , Testes de Sensibilidade Microbiana
4.
Arch Virol ; 169(5): 102, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38630315

RESUMO

A highly divergent bovine calicivirus was identified in an Indian calf with enteritis. The whole genome of this virus was sequenced, revealing distinct amino acid motifs in the polyprotein encoded by open reading frame 1 (ORF1) that are unique to caliciviruses. Phylogenetic analysis showed that it was related to members of the genus Nebovirus of the family Caliciviridae. Although it showed only 33.7-34.2% sequence identity in the VP1 protein to the nebovirus prototype strains, it showed 90.6% identity in VP1 to Kirklareli virus, a nebovirus detected in calves with enteritis in Turkey in 2012. An in-house-designed and optimized reverse transcription polymerase chain reaction (RT-PCR) assay was used to screen 120 archived bovine diarrhoeic fecal samples, 40 each from the Indian states of Uttar Pradesh, Haryana, and Himachal Pradesh, revealing frequent circulation of these divergent caliciviruses in the bovine population, with an overall positivity rate of 64.17% (77/120). This underscores the importance of conducting a comprehensive investigation of the prevalence of these divergent caliciviruses and assessing their associations with other pathogens responsible for enteritis in India.


Assuntos
Caliciviridae , Enterite , Vírus de RNA , Bovinos , Animais , Filogenia , Caliciviridae/genética , Índia/epidemiologia
5.
J Appl Microbiol ; 135(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38341275

RESUMO

AIMS: The study aims to explore antifungal properties of bacillibactin siderophore produced by the plant growth-promoting rhizobacterium (PGPR) Bacillus subtilis against fungal phytopathogens Alternaria porri and Fusarium equiseti isolated from Solanum lycopersicum and Solanum melongena plants. METHODS AND RESULTS: Alternaria porri and F. equiseti were isolated from infected plants of eggplant and tomato, respectively. A plate assay was employed to assess the effect of bacillibactin against the phytopathogens. The antifungal potential of the PGPR was evaluated by estimation of dry fungal biomass, visualization of cellular deformity using compound and scanning electron microscopy, antioxidative enzyme assay and analysis of membrane damage via using lipid peroxidation. Inductively coupled plasma atomic emission spectroscopy (ICP-AES) analysis was employed to investigate changes in intracellular iron content. The impact of bacillibactin on pathogenesis was evaluated by infecting detached leaves of S. lycopersicum and S. melongena plants with both the pathogens and treating the infected leaves with bacillibactin. Leaves were further investigated for ROS accumulation, extent of necrosis and cell death. Our findings revealed significant damage to the hyphal structure of A. porri and F. equiseti following treatment with bacillibactin. Biomass reduction, elevated antioxidative enzyme levels, and membrane damage further substantiated the inhibitory effects of the siderophore on fungal growth. ICP-AES analysis indicates an increase in intracellular iron content suggesting enhanced iron uptake facilitated by bacillibactin. Moreover, application of 1500 µg ml-1 bacillibactin on infected leaves demonstrated a substantial inhibition of ROS accumulation, necrosis, and cell death upon bacillibactin treatment. CONCLUSIONS: This study confirms the potent antagonistic activity of bacillibactin against both the phytopathogens A. porri and F. equiseti growth, supporting its potential as a promising biological control agent for fungal plant diseases. Bacillibactin-induced morphological, physiological, and biochemical alterations in the isolated fungi and pathogen-infected leaves highlight the prospects of bacillibactin as an effective and sustainable solution to mitigate economic losses associated with fungal infections in vegetable crops.


Assuntos
Alternaria , Solanum lycopersicum , Solanum , Antifúngicos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Solanum/metabolismo , Sideróforos/farmacologia , Produtos Agrícolas/metabolismo , Ferro , Necrose , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia
6.
Nano Lett ; 23(5): 1767-1773, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36827496

RESUMO

Transition-metal dichalcogenides (TMDs) have demonstrated a wide range of novel photonic, optoelectronic, and correlated electron phenomena for more than a decade. However, the coherent dynamics of their excitons, including possibly long dephasing times and their sensitivity to spatial heterogeneities, are still poorly understood. Here we implement adiabatic plasmonic nanofocused four-wave mixing (FWM) to image the coherent electron dynamics in monolayer WSe2. We observe nanoscale heterogeneities at room temperature with dephasing ranging from T2 ≲ 5 to T2 ≳ 60 fs on length scales of 50-100 nm. We further observe a counterintuitive anticorrelation between FWM intensity and T2, with the weakest FWM emission at locations of longest coherence. We interpret this behavior as a nonlocal nano-optical interplay between spatial coherence of the nonlinear polarization and disorder-induced scattering. The results highlight the challenges associated with heterogeneities in TMDs limiting their photophysical properties, yet also the potential of their novel nonlinear optical phenomena.

7.
J Biol Chem ; 298(5): 101898, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35378126

RESUMO

Protein-protein interactions drive various biological processes in healthy as well as disease states. The transcription factor c-Myc plays a crucial role in maintaining cellular homeostasis, and its deregulated expression is linked to various human cancers; therefore, it can be considered a viable target for cancer therapeutics. However, the structural heterogeneity of c-Myc due to its disordered nature poses a major challenge to drug discovery. In the present study, we used an in silico alanine scanning mutagenesis approach to identify "hot spot" residues within the c-Myc/Myc-associated factor X interface, which is highly disordered and has not yet been systematically analyzed for potential small molecule binding sites. We then used the information gained from this analysis to screen potential inhibitors using a conformation ensemble approach. The fluorescence-based biophysical experiments showed that the identified hit molecules displayed noncovalent interactions with these hot spot residues, and further cell-based experiments showed substantial in vitro potency against diverse c-Myc-expressing cancer/stem cells by deregulating c-Myc activity. These biophysical and computational studies demonstrated stable binding of the hit compounds with the disordered c-Myc protein. Collectively, our data indicated effective drug targeting of the disordered c-Myc protein via the determination of hot spot residues in the c-Myc/Myc-associated factor X heterodimer.


Assuntos
Descoberta de Drogas , Fator X , Técnicas Genéticas , Proteínas Proto-Oncogênicas c-myc , Fator X/metabolismo , Humanos , Conformação Molecular , Mutagênese , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Proteínas Proto-Oncogênicas c-myc/química
8.
J Am Chem Soc ; 145(2): 1433-1440, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36580662

RESUMO

The scientific community has found immense difficulty to focus on the generation of chiral intermetallics compared to the chiral molecular structure, probably due to the technical difficulty in producing them as no general controlled protocol is available. Herein, using a conventional metal flux technique, we have discovered a new ternary intermetallic Co3Ni3Ga8, substituting Co at the Ni sublattice in a highly symmetric Ni3Ga4 (Ia3̅d). Co3Ni3Ga8 crystallizes in the I4132 space group, a Sohncke type, and can host the chiral structure. To the best of our knowledge, this is the first report of a ternary intermetallic crystallizing in this space group. The chiral structure of Co3Ni3Ga8 is comprehensively mapped by various techniques such as single-crystal X-ray diffraction (XRD), synchrotron powder XRD, X-ray absorption spectroscopy (XAS), scanning transmission electron microscopy (STEM) and theoretically studied using density functional theory. The discovery of this chiral compound can inspire the researchers to design hidden ternary chiral intermetallics to study the exotic electrical and magnetic properties.

9.
Funct Integr Genomics ; 23(4): 296, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37697159

RESUMO

Given the future demand for food crops, increasing crop productivity in drought-prone rainfed areas has become essential. Drought-tolerant varieties are warranted to solve this problem in major crops, with drought tolerance as a high-priority trait for future research. Maize is one such crop affected by drought stress, which limits production, resulting in substantial economic losses. It became a more serious issue due to global climate change. The most drought sensitive among all stages of maize is the reproductive stages and the most important for overall maize production. The exact molecular basis of reproductive drought sensitivity remains unclear due to genes' complex regulation of drought stress. Understanding the molecular biology and signaling of the unexplored area of reproductive drought tolerance will provide an opportunity to develop climate-smart drought-tolerant next-generation maize cultivars. In recent decades, significant progress has been made in maize to understand the drought tolerance mechanism. However, improving maize drought tolerance through breeding is ineffective due to the complex nature and multigenic control of drought traits. With the help of advanced breeding techniques, molecular genetics, and a precision genome editing approach like CRISPR-Cas, candidate genes for drought-tolerant maize can be identified and targeted. This review summarizes the effects of drought stress on each growth stage of maize, potential genes, and transcription factors that determine drought tolerance. In addition, we discussed drought stress sensing, its molecular mechanisms, different approaches to developing drought-resistant maize varieties, and how molecular breeding and genome editing will help with the current unpredictable climate change.


Assuntos
Secas , Zea mays , Zea mays/genética , Melhoramento Vegetal , Resistência à Seca , Produtos Agrícolas/genética , Percepção
10.
Funct Integr Genomics ; 23(3): 210, 2023 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-37355501

RESUMO

Millets are nutrient-rich (nutri-rich) cereals with climate resilience attributes. However, its full productive potential is not realized due to the lack of a focused yield improvement approach, as evidenced by the available literature. Also, the lack of well-characterized genomic resources significantly limits millet improvement. But the recent availability of genomic data and advancement in omics tools has shown its enormous potential to enhance the efficiency and precision faced by conventional breeding in millet improvement. The development of high throughput genotyping platforms based on next-generation sequencing (NGS) has provided a low-cost method for genomic information, specifically for neglected nutri-rich cereals with the availability of a limited number of reference genome sequences. NGS has created new avenues for millet biotechnological interventions such as mutation-based study, GWAS, GS, and other omics technologies. The simultaneous discovery of high-throughput markers and multiplexed genotyping platform has aggressively aided marker-assisted breeding for millet improvement. Therefore, omics technology offers excellent opportunities to explore and combine useful variations for targeted traits that could impart high nutritional value to high-yielding cultivars under changing climatic conditions. In millet improvement, an in-depth account of NGS, integrating genomics data with different biotechnology tools, is reviewed in this context.


Assuntos
Milhetes , Melhoramento Vegetal , Milhetes/genética , Genômica , Grão Comestível/genética , Fenótipo
11.
Phys Rev Lett ; 131(9): 096902, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37721822

RESUMO

In mirror-symmetric systems, there is a possibility of the realization of extended gapless electronic states characterized as nodal lines or rings. Strain induced modifications to these states lead to the emergence of different classes of nodal rings with qualitatively different physical properties. Here we study optical response and the electromagnetic wave propagation in type I nodal ring semimetals, in which the low-energy quasiparticle dispersion is parabolic in momentum k_{x} and k_{y} and is linear in k_{z}. This leads to a highly anisotropic dielectric permittivity tensor in which the optical response is plasmonic in one spatial direction and dielectric in the other two directions. The resulting normal modes (polaritons) in the bulk material become hyperbolic over a broad frequency range, which is furthermore tunable by the doping level. The propagation, reflection, and polarization properties of the hyperbolic polaritons not only provide valuable information about the electronic structure of these fascinating materials in the most interesting region near the nodal rings but also pave the way to tunable hyperbolic materials with applications ranging from anomalous refraction and waveguiding to perfect absorption in ultrathin subwavelength films.

12.
Langmuir ; 39(13): 4789-4798, 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-36940478

RESUMO

Dynamic wetting by liquids on solid surfaces depends on several aspects such as surface energy, roughness, and interfacial tension, among many others. Copper (Cu), gold (Au), aluminum (Al), and silicon (Si) are a few of the most important metals that are used extensively as substrates in various industrial and biomedical applications. Metals are etched frequently on different crystal planes for fabrication purposes. Etching exposes distinct crystal planes that may come in contact with the liquids when used for different applications. The interaction of the crystal planes with the liquid that comes in contact with the solid dictates the wetting behavior of the surface. This necessitates the importance of understanding how various crystal planes of the same metals behave under similar conditions. Herein, three specific crystal planes, namely, (1 0 0), (1 1 0), and (1 1 1), are investigated at a molecular scale for the above-mentioned metals. The dynamic contact angle and contact diameter trends revealed that the relatively hydrophobic surfaces (Cu, Si) tend to reach their equilibrium contact angle faster compared to the hydrophilic substrates (Al, Au). Molecular kinetic theory is used to estimate the three-phase contact line friction which is found to be higher for (1 1 1) planes. Further, a consistent potential energy distribution variation is observed for the crystal lattice of (1 0 0), (1 1 0), and (1 1 1). These findings can be used as a guideline to determine the factors needed to completely describe a dynamic wetting phenomenon of the droplet over the different crystal planes. The understanding will be of great use in deciding experimental strategies where fabricated different crystal planes would be required to have a liquid contact.

13.
Crit Rev Food Sci Nutr ; 63(14): 2004-2017, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34459296

RESUMO

Fruits and vegetables (F&V) are the second highest recommended foods, rich in antioxidants, vitamins and minerals, vital for building immunity against chronic diseases. F&V processing involves particle size reduction, for which different types of homogenizers, categorized as mechanical homogenizers, pressure homogenizers and ultrasonic homogenizers are used. The review discusses different types of homogenizers, their working mechanism, and application in F&V processing. Among mechanical homogenizers, knife mills are used for primary size reduction, ball mills for the micronization of dried F&V and rotor-stator homogenizers for emulsification. Use of the ultrasonic homogenizer is limited to extraction of bioactive compounds or as a pre-treatment for dehydration of F&V. High-pressure homogenizers are most widely used and reported due to the synergistic effect of homogenization and temperature increase, resulting in longer shelf-life and better physicochemical properties of the product. Additionally, the review also explains the effect of homogenization on the physicochemical, sensory and nutraceutical properties of the product.


Assuntos
Frutas , Verduras , Antioxidantes , Vitaminas
14.
J Oral Pathol Med ; 52(10): 895-903, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37872712

RESUMO

OBJECTIVES: This review aims to analyse the recurrence rate in BRAFv600e+ and BRAFv600e- ameloblastomas and explore its association with clinicopathological variables. METHODS: A comprehensive search was conducted using databases including PubMed, Embase, Cochrane Central Register of Controlled Trials, Clinicaltrials.gov, Google Scholar and grey literature, without any limitation on start date or language up to 20 June 2023. A random effect meta-analysis was conducted and Metaregression analyses were performed based on available clinicopathological factors. RESULTS: Fifteen studies met the criteria for meta-analysis of outcomes. There was no significant difference in overall recurrence rates between the two groups (risk difference = 0.001, p-value = 0.987). Increasing male:female ratio in the BRAFv600e+ group was associated with a lower reported recurrence, suggesting a higher recurrence rate in females. The odds of having mandibular lesion were four times higher in BRAFv600e+ cases compared to BRAFv600e- cases (confidence interval: 2.121-7.870, p < 0.001, I2 = 28.37%). CONCLUSION: Within the BRAFv600e+ group, females showed a higher reported recurrence rate. This specific clinical group may benefit from BRAFv600e mutation investigation and potential upscaled surgical treatment and additional BRAF inhibitor therapy, which needs validation in future studies.


Assuntos
Ameloblastoma , Humanos , Masculino , Feminino , Ameloblastoma/genética , Ameloblastoma/patologia , Proteínas Proto-Oncogênicas B-raf/genética , Mutação , Terapia de Alvo Molecular
15.
Int Urogynecol J ; 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37642668

RESUMO

AIM: Validation of the recently published newer clinical scoring system for bladder pain syndrome/interstitial cystitis and comparison of the results with the pre-existing standard O'Leary-Sant score. INTRODUCTION: The symptoms are our primary guide to disease severity analysis, treatment, and response monitoring. The combined ICSI/ICPI (O'Leary-Sant Interstitial Cystitis Symptom and Problem Index) consist of a four-item symptom and problem index focusing on urgency, frequency, nocturia, and pain. A new scale, assigning more weight to pain and nocturia and adding the domains of sexual dysfunction and psychological impact, has been published by one of the authors (El Khoudary et al. J Women's Health 2002. 18:1361-1368; 7). MATERIAL AND METHODS: This is a prospective study conducted to validate a newer clinical scoring system, namedht e 'Apollo Clinical Scoring' (ACS) system for patients with bladder pain syndrome/ interstitial cystitis (BPS/IC), and to compare its outcome with the simultaneously applied standard O'Leary-Sant (OLS) score. Thirty-five patients of BPS/IC diagnosed using the ESSIC definition were enrolled in the study and followed for 6 months. Intraclass correlation coefficient (ICC) for test-retest reliability, and Cronbach's α for measure of internal consistency, were applied to both scoring systems. RESULTS: Intraclass correlation coefficient for ACS was 0.715 and for OLS was 0.689. Cronbach's α for ACS was 0.736 and for OLS was 0.698. CONCLUSION: The present study suggests that the recently devised Apollo Clinical Scoring (ACS) system for patients of BPS/IC is internally consistent and a reliable scoring system. When compared with OLS in parallel setting, the newer ACS appeared to be marginally better.

16.
Mycoses ; 66(6): 515-526, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36790120

RESUMO

BACKGROUND: The aetiology of the major outbreak of COVID-19-associated mucormycosis (CAM) in India in spring 2021 remains incompletely understood. Herein, we provide a multifaceted and multi-institutional analysis of clinical, pathogen-related, environmental and healthcare-related factors during CAM outbreak in the metropolitan New Delhi area. METHODS: We reviewed medical records of all patients diagnosed with biopsy-proven CAM (n = 50) at 7 hospitals in the New Delhi, and NCR area in April-June 2021. Two multivariate logistic regression models were used to compare clinical characteristics of CAM cases with COVID-19-hospitalised contemporary patients as controls (n = 69). Additionally, meteorological parameters and mould spore concentrations in outdoor air were analysed. Selected hospital fomites were cultured. Mucorales isolates from CAM patients were analysed by ITS sequencing and whole-genome sequencing (WGS). RESULTS: Independent risk factors for CAM identified by multivariate analysis were previously or newly diagnosed diabetes mellitus, active cancer and severe COVID-19 infection. Supplemental oxygen, remdesivir therapy and ICU admission for COVID-19 were associated with reduced CAM risk. The CAM incidence peak was preceded by an uptick in environmental spore concentrations in the preceding 3-4 weeks that correlated with increasing temperature, high evaporation and decreasing relative humidity. Rhizopus was the most common genus isolated, but we also identified two cases of the uncommon Mucorales, Lichtheimia ornata. WGS found no clonal population of patient isolates. No Mucorales were cultured from hospital fomites. CONCLUSIONS: An intersection of host and environmental factors contributed to the emergence of CAM. Surrogates of access to advanced COVID-19 treatment were associated with lower CAM risk.


Assuntos
COVID-19 , Mucormicose , Humanos , Mucormicose/tratamento farmacológico , Tratamento Farmacológico da COVID-19 , COVID-19/epidemiologia , COVID-19/complicações , Fatores de Risco , Surtos de Doenças , Índia/epidemiologia
17.
Entropy (Basel) ; 25(2)2023 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-36832606

RESUMO

The main motivation of this work is to study and obtain some reversible and DNA codes of length n with better parameters. Here, we first investigate the structure of cyclic and skew cyclic codes over the chain ring R:=F4[v]/⟨v3⟩. We show an association between the codons and the elements of R using a Gray map. Under this Gray map, we study reversible and DNA codes of length n. Finally, several new DNA codes are obtained that have improved parameters than previously known codes. We also determine the Hamming and the Edit distances of these codes.

18.
Angew Chem Int Ed Engl ; 62(9): e202216613, 2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36537874

RESUMO

We present surface reconstruction-induced C-C coupling whereby CO2 is converted into ethylene. The wurtzite phase of CuGaS2. undergoes in situ surface reconstruction, leading to the formation of a thin CuO layer over the pristine catalyst, which facilitates selective conversion of CO2 to ethylene (C2 H4 ). Upon illumination, the catalyst efficiently converts CO2 to C2 H4 with 75.1 % selectivity (92.7 % selectivity in terms of Relectron ) and a 20.6 µmol g-1 h-1 evolution rate. Subsequent spectroscopic and microscopic studies supported by theoretical analysis revealed operando-generated Cu2+ , with the assistance of existing Cu+ , functioning as an anchor for the generated *CO and thereby facilitating C-C coupling. This study demonstrates strain-induced in situ surface reconstruction leading to heterojunction formation, which finetunes the oxidation state of Cu and modulates the CO2 reduction reaction pathway to selective formation of ethylene.

19.
Semin Cancer Biol ; 70: 71-84, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32479952

RESUMO

The commensal microbiome of humans has co-evolved for thousands of years. The microbiome regulates human health and is also linked to several diseases, including cancer. The advances in next-generation sequencing have significantly contributed to our understanding of the microbiome and its association with cancer and cancer therapy. Recent studies have highlighted a close relationship of the microbiome to the pharmacological effect of chemotherapy and immunotherapy. The chemo-drugs usually interfere with the host immune system and reduces the microbiome diversity inside the body, which in turn leads to decreased efficacy of these drugs. The human microbiome, specifically the gut microbiome, increases the potency of chemo-drugs through metabolism, enzymatic degradation, ecological differences, and immunomodulation. Recent research exploits the involvement of microbiome to shape the efficacy and decrease the toxicity of these chemo-drugs. In this review, we have highlighted the recent development in understanding the relationship of the human microbiome with cancer and also emphasize on various roles of the microbiome in the modulation of cancer therapy. Additionally, we also summarize the ongoing research focussed on the improved efficacy of chemotherapy and immunotherapy using the host microbiome.


Assuntos
Antineoplásicos/administração & dosagem , Microbioma Gastrointestinal , Interações entre Hospedeiro e Microrganismos , Imunoterapia/métodos , Neoplasias/tratamento farmacológico , Prebióticos/administração & dosagem , Animais , Humanos , Imunomodulação , Neoplasias/imunologia , Neoplasias/microbiologia
20.
J Biol Chem ; 297(1): 100903, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34157284

RESUMO

c-Myc is a transcription factor that plays a crucial role in cellular homeostasis, and its deregulation is associated with highly aggressive and chemotherapy-resistant cancers. After binding with partner MAX, the c-Myc-MAX heterodimer regulates the expression of several genes, leading to an oncogenic phenotype. Although considered a crucial therapeutic target, no clinically approved c-Myc-targeted therapy has yet been discovered. Here, we report the discovery via computer-aided drug discovery of a small molecule, L755507, which functions as a c-Myc inhibitor to efficiently restrict the growth of diverse Myc-expressing cells with low micromolar IC50 values. L755507 successfully disrupts the c-Myc-MAX heterodimer, resulting in decreased expression of c-Myc target genes. Spectroscopic and computational experiments demonstrated that L755507 binds to the c-Myc peptide and thereby stabilizes the helix-loop-helix conformation of the c-Myc transcription factor. Taken together, this study suggests that L755507 effectively inhibits the c-Myc-MAX heterodimerization and may be used for further optimization to develop a c-Myc-targeted antineoplastic drug.


Assuntos
Antineoplásicos/química , Apoptose/efeitos dos fármacos , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/química , Multimerização Proteica/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-myc/química , Antineoplásicos/farmacologia , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Sítios de Ligação , Descoberta de Drogas , Células HT29 , Humanos , Simulação de Acoplamento Molecular , Ligação Proteica/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-myc/metabolismo , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia
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