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1.
Plant Cell ; 35(3): 1134-1159, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36585808

RESUMO

Fungal pathogens deploy a barrage of secreted effectors to subvert host immunity, often by evading, disrupting, or altering key components of transcription, defense signaling, and metabolic pathways. However, the underlying mechanisms of effectors and their host targets are largely unexplored in necrotrophic fungal pathogens. Here, we describe the effector protein Ascochyta rabiei PEXEL-like Effector Candidate 25 (ArPEC25), which is secreted by the necrotroph A. rabiei, the causal agent of Ascochyta blight disease in chickpea (Cicer arietinum), and is indispensable for virulence. After entering host cells, ArPEC25 localizes to the nucleus and targets the host LIM transcription factor CaßLIM1a. CaßLIM1a is a transcriptional regulator of CaPAL1, which encodes phenylalanine ammonia lyase (PAL), the regulatory, gatekeeping enzyme of the phenylpropanoid pathway. ArPEC25 inhibits the transactivation of CaßLIM1a by interfering with its DNA-binding ability, resulting in negative regulation of the phenylpropanoid pathway and decreased levels of intermediates of lignin biosynthesis, thereby suppressing lignin production. Our findings illustrate the role of fungal effectors in enhancing virulence by targeting a key defense pathway that leads to the biosynthesis of various secondary metabolites and antifungal compounds. This study provides a template for the study of less explored necrotrophic effectors and their host target functions.


Assuntos
Ascomicetos , Cicer , Fatores de Transcrição , Ascomicetos/genética , Ascomicetos/metabolismo , Cicer/genética , Cicer/metabolismo , Cicer/microbiologia , Lignina/metabolismo , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
2.
Mol Microbiol ; 121(5): 1063-1078, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38558112

RESUMO

Metalloprotease-gp63 is a virulence factor secreted by Leishmania. However, secretory pathway in Leishmania is not well defined. Here, we cloned and expressed the GRASP homolog from Leishmania. We found that Leishmania expresses one GRASP homolog of 58 kDa protein (LdGRASP) which localizes in LdRab1- and LPG2-positive Golgi compartment in Leishmania. LdGRASP was found to bind with COPII complex, LdARF1, LdRab1 and LdRab11 indicating its role in ER and Golgi transport in Leishmania. To determine the function of LdGRASP, we generated LdGRASP knockout parasites using CRISPR-Cas9. We found fragmentation of Golgi in Ld:GRASPKO parasites. Our results showed enhanced transport of non-GPI-anchored gp63 to the cell surface leading to higher secretion of this form of gp63 in Ld:GRASPKO parasites in comparison to Ld:WT cells. In contrast, we found that transport of GPI-anchored gp63 to the cell surface is blocked in Ld:GRASPKO parasites and thereby inhibits its secretion. The overexpression of dominant-negative mutant of LdRab1 or LdSar1 in Ld:GRASPKO parasites significantly blocked the secretion of non-GPI-anchored gp63. Interestingly, we found that survival of transgenic parasites overexpressing Ld:GRASP-GFP is significantly compromised in macrophages in comparison to Ld:WT and Ld:GRASPKO parasites. These results demonstrated that LdGRASP differentially regulates Ldgp63 secretory pathway in Leishmania.


Assuntos
Metaloendopeptidases , Proteínas de Protozoários , Fatores de Virulência , Fatores de Virulência/metabolismo , Fatores de Virulência/genética , Proteínas de Protozoários/metabolismo , Proteínas de Protozoários/genética , Metaloendopeptidases/metabolismo , Metaloendopeptidases/genética , Complexo de Golgi/metabolismo , Retículo Endoplasmático/metabolismo , Macrófagos/parasitologia , Macrófagos/metabolismo , Animais , Leishmania/metabolismo , Leishmania/genética , Transporte Proteico , Sistemas CRISPR-Cas , Proteínas da Matriz do Complexo de Golgi/metabolismo , Proteínas da Matriz do Complexo de Golgi/genética
3.
J Chem Phys ; 160(22)2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38856070

RESUMO

We present an experimental study of multiple-electron capture-induced fragmentation dynamics of Ar2m+ (4 ≤m≤ 7) dimer ions in 4 keV/u Ar8+-Ar2 collisions. The fragment recoil ion pairs and the charge-changing projectiles are coincidentally measured using a double coincidence technique. The branching ratios between the different charge-sharing fragmentation channels show an inherent enhancement of the asymmetric channels. The kinetic energy release (KER) distributions for the associated electron capture process show a shift in the mean KER values toward the higher side with increasing capture stabilization. The interplay between the different projectile autoionization processes sheds light on the energy depositions to the system during collisions. The Coulomb potential energy curves give a physical insight into the role of the projectile final states in the dimer fragmentation dynamics. The dimer-axis orientation-dependent cross sections for the asymmetric fragmentation channels reveal a forward-backward asymmetry that arises from the geometry of the collision system. Our findings thus give insight into the impact parameter-controlled fragmentation dynamics of multiply charged Ar2m+ dimer ions in highly charged ion-dimer slow collisions.

4.
PLoS Genet ; 17(5): e1009137, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33999937

RESUMO

Polarized hyphal growth of filamentous pathogenic fungi is an essential event for host penetration and colonization. The long-range early endosomal trafficking during hyphal growth is crucial for nutrient uptake, sensing of host-specific cues, and regulation of effector production. Bin1/Amphiphysin/Rvs167 (BAR) domain-containing proteins mediate fundamental cellular processes, including membrane remodeling and endocytosis. Here, we identified a F-BAR domain protein (ArF-BAR) in the necrotrophic fungus Ascochyta rabiei and demonstrate its involvement in endosome-dependent fungal virulence on the host plant Cicer arietinum. We show that ArF-BAR regulates endocytosis at the hyphal tip, localizes to the early endosomes, and is involved in actin dynamics. Functional studies involving gene knockout and complementation experiments reveal that ArF-BAR is necessary for virulence. The loss-of-function of ArF-BAR gene results in delayed formation of apical septum in fungal cells near growing hyphal tip that is crucial for host penetration, and impaired secretion of a candidate effector having secretory signal peptide for translocation across the endoplasmic reticulum membrane. The mRNA transcripts of ArF-BAR were induced in response to oxidative stress and infection. We also show that ArF-BAR is able to tubulate synthetic liposomes, suggesting the functional role of F-BAR domain in membrane tubule formation in vivo. Further, our studies identified a stress-induced transcription factor, ArCRZ1 (Calcineurin-responsive zinc finger 1), as key transcriptional regulator of ArF-BAR expression. We propose a model in which ArCRZ1 functions upstream of ArF-BAR to regulate A. rabiei virulence through a mechanism that involves endocytosis, effector secretion, and actin cytoskeleton regulation.


Assuntos
Actinas/metabolismo , Ascomicetos/citologia , Ascomicetos/patogenicidade , Cicer/microbiologia , Endocitose , Proteínas Fúngicas/metabolismo , Ascomicetos/genética , Ascomicetos/metabolismo , Núcleo Celular/metabolismo , Citoesqueleto/metabolismo , Endocitose/genética , Endossomos/metabolismo , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica , Lipossomos/metabolismo , Mutação , Estresse Oxidativo , Doenças das Plantas/microbiologia , Regiões Promotoras Genéticas/genética , Virulência/genética
5.
Fungal Genet Biol ; 166: 103798, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37059379

RESUMO

The Spot Blotch (SB) caused by hemibiotrophic fungal pathogen Bipolaris sorokiniana is one of the most devastating wheat diseases leading to 15-100% crop loss. However, the biology of Triticum-Bipolaris interactions and host immunity modulation by secreted effector proteins remain underexplored. Here, we identified a total of 692 secretory proteins including 186 predicted effectors encoded by B. sorokiniana genome. Gene Ontology categorization showed that these proteins belong to cellular, metabolic and signaling processes, and exhibit catalytic and binding activities. Further, we functionally characterized a cysteine-rich, B. sorokiniana Candidate Effector 66 (BsCE66) that was induced at 24-96 hpi during host colonization. The Δbsce66 mutant did not show vegetative growth defects or stress sensitivity compared to wild-type, but developed drastically reduced necrotic lesions upon infection in wheat plants. The loss-of-virulence phenotype was rescued upon complementing the Δbsce66 mutant with BsCE66 gene. Moreover, BsCE66 does not form homodimer and conserved cysteine residues form intra-molecular disulphide bonds. BsCE66 localizes to the host nucleus and cytosol, and triggers a strong oxidative burst and cell death in Nicotiana benthamiana. Overall, our findings demonstrate that BsCE66 is a key virulence factor that is necessary for host immunity modulation and SB disease progression. These findings would significantly improve our understanding of Triticum-Bipolaris interactions and assist in the development of SB resistant wheat varieties.


Assuntos
Ascomicetos , Bipolaris , Virulência/genética , Triticum/microbiologia , Cisteína/genética , Doenças das Plantas/microbiologia
6.
J Assoc Physicians India ; 71(9): 95-100, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38700308

RESUMO

ß-adrenergic blocker group of medicines has been traditionally used to control high blood pressure since propranolol was discovered by Sir James Black almost 50 years ago. They were the drug of choice in hypertension (HTN) associated with ischemic heart disease, tachyarrhythmias including atrial fibrillation (AF), and anxiety. Congestive cardiac failure was a relative contraindication, but with major advances in science, it became an absolute indication. However, with the advent of newer antihypertensives, especially calcium channel blocker (CCBs) and renin-angiotensin-aldosterone inhibitors, comparative studies were done, and depending on the outcomes of these trials, ß-blockers (BBs) were downgraded to fourth or fifth-line therapy, except in the conditions mentioned above, along with HTN in pregnancy. But clinicians never rejected BBs as important antihypertensives, as evidenced by various real-world data. Also, many investigators found the unfairness of the trial designs where BBs were poor performers. The fact that all BBs are not similar, and differ widely in various properties, added to the question of downgrading all BBs on the basis of trials mostly with atenolol, which is also used once daily. Moreover, trials like ASCOT could not show the reduction of most of the events after long-term follow-up with the use of newer antihypertensives. Added to the issue is the fact that the majority of the trials used BBs with diuretics, and selecting BBs as the sole nonperformer appears to be unjustified and illogical. The recent European Society of HTN (ESH) guideline reemphasized the fact that all the five major classes of antihypertensives, including BBs, can be used as first-line medicine and also can be used interchangeably. Moreover, apart from the traditional indications of BBs, this guideline listed nineteen other conditions, including high heart rate (HR), chronic obstructive pulmonary disease (COPD), and obstructive sleep apnoea, as the conditions where BBs are preferred agents as antihypertensive. So, the life history of BBs in HTN has completed a full cycle, and they are ready now for prime time again. How to cite this article: Ray S, Saboo B, Joshi S, et al. ß-blockers as the First Line of Treatment for Hypertension Management. J Assoc Physicians India 2023;71(9):95-100.


Assuntos
Antagonistas Adrenérgicos beta , Anti-Hipertensivos , Hipertensão , Humanos , Antagonistas Adrenérgicos beta/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Hipertensão/tratamento farmacológico , Medicina Baseada em Evidências , Guias de Prática Clínica como Assunto
7.
Mol Plant Microbe Interact ; 35(11): 1034-1047, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35939621

RESUMO

Ascochyta blight (AB) caused by the filamentous fungus Ascochyta rabiei is a major threat to global chickpea production. The mechanisms underlying chickpea response to A. rabiei remain elusive to date. Here, we investigated the comparative transcriptional dynamics of AB-resistant and -susceptible chickpea genotypes upon A. rabiei infection, to understand the early host defense response. Our findings revealed that AB-resistant plants underwent rapid and extensive transcriptional reprogramming compared with a susceptible host. At the early stage (24 h postinoculation [hpi]), mainly cell-wall remodeling and secondary metabolite pathways were highly activated, while differentially expressed genes related to signaling components, such as protein kinases, transcription factors, and hormonal pathways, show a remarkable upsurge at 72 hpi, especially in the resistant genotype. Notably, our data suggest an imperative role of jasmonic acid, ethylene, and abscisic acid signaling in providing immunity against A. rabiei. Furthermore, gene co-expression networks and modules corroborated the importance of cell-wall remodeling, signal transduction, and phytohormone pathways. Hub genes such as MYB14, PRE6, and MADS-SOC1 discovered in these modules might be the master regulators governing chickpea immunity. Overall, we not only provide novel insights for comprehensive understanding of immune signaling components mediating AB resistance and susceptibility at early Cicer-Ascochyta interactions but, also, offer a valuable resource for developing AB-resistant chickpea. [Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Assuntos
Cicer , Cicer/genética , Cicer/microbiologia , Transcriptoma/genética , Doenças das Plantas/microbiologia
8.
Planta ; 255(2): 46, 2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-35076815

RESUMO

MAIN CONCLUSION: Advancements in sequencing, genotyping, and computational technologies during the last decade (2011-2020) enabled new forward-genetic approaches, which subdue the impediments of precise gene mapping in varied crops. The modern crop improvement programs rely heavily on two major steps-trait-associated QTL/gene/marker's identification and molecular breeding. Thus, it is vital for basic and translational crop research to identify genomic regions that govern the phenotype of interest. Until the advent of next-generation sequencing, the forward-genetic techniques were laborious and time-consuming. Over the last 10 years, advancements in the area of genome assembly, genotyping, large-scale data analysis, and statistical algorithms have led faster identification of genomic variations regulating the complex agronomic traits and pathogen resistance. In this review, we describe the latest developments in genome sequencing and genotyping along with a comprehensive evaluation of the last 10-year headways in forward-genetic techniques that have shifted the focus of plant research from model plants to diverse crops. We have classified the available molecular genetic methods under bulk-segregant analysis-based (QTL-seq, GradedPool-Seq, QTG-Seq, Exome QTL-seq, and RapMap), target sequence enrichment-based (RenSeq, AgRenSeq, and TACCA), and mutation-based groups (MutMap, NIKS algorithm, MutRenSeq, MutChromSeq), alongside improvements in classical mapping and genome-wide association analyses. Newer methods for outcrossing, heterozygous, and polyploid plant genetics have also been discussed. The use of k-mers has enriched the nature of genetic variants which can be utilized to identify the phenotype-causing genes, independent of reference genomes. We envisage that the recent methods discussed herein will expand the repertoire of useful alleles and help in developing high-yielding and climate-resilient crops.


Assuntos
Estudo de Associação Genômica Ampla , Locos de Características Quantitativas , Mapeamento Cromossômico , Genoma de Planta/genética , Biologia Molecular , Fenótipo , Melhoramento Vegetal , Locos de Características Quantitativas/genética
9.
J Med Internet Res ; 24(1): e29595, 2022 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-35084336

RESUMO

BACKGROUND: One-third of the US population experiences sleep loss, with the potential to impair physical and cognitive performance, reduce productivity, and imperil safety during work and daily activities. Computer-based fatigue-management systems with the ability to predict the effects of sleep schedules on alertness and identify safe and effective caffeine interventions that maximize its stimulating benefits could help mitigate cognitive impairment due to limited sleep. To provide these capabilities to broad communities, we previously released 2B-Alert Web, a publicly available tool for predicting the average alertness level of a group of individuals as a function of time of day, sleep history, and caffeine consumption. OBJECTIVE: In this study, we aim to enhance the capability of the 2B-Alert Web tool by providing the means for it to automatically recommend safe and effective caffeine interventions (time and dose) that lead to optimal alertness levels at user-specified times under any sleep-loss condition. METHODS: We incorporated a recently developed caffeine-optimization algorithm into the predictive models of the original 2B-Alert Web tool, allowing the system to search for and identify viable caffeine interventions that result in user-specified alertness levels at desired times of the day. To assess the potential benefits of this new capability, we simulated four sleep-deprivation conditions (sustained operations, restricted sleep with morning or evening shift, and night shift with daytime sleep) and compared the alertness levels resulting from the algorithm's recommendations with those based on the US Army caffeine-countermeasure guidelines. In addition, we enhanced the usability of the tool by adopting a drag-and-drop graphical interface for the creation of sleep and caffeine schedules. RESULTS: For the 4 simulated conditions, the 2B-Alert Web-proposed interventions increased mean alertness by 36% to 94% and decreased peak alertness impairment by 31% to 71% while using equivalent or smaller doses of caffeine as the corresponding US Army guidelines. CONCLUSIONS: The enhanced capability of this evidence-based, publicly available tool increases the efficiency by which diverse communities of users can identify safe and effective caffeine interventions to mitigate the effects of sleep loss in the design of research studies and work and rest schedules.


Assuntos
Cafeína , Mídias Sociais , Atenção , Cafeína/farmacologia , Humanos , Desempenho Psicomotor , Sono , Vigília
10.
Angew Chem Int Ed Engl ; 61(40): e202209374, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-35959923

RESUMO

Natural product (NP)-inspired design principles provide invaluable guidance for bioactive compound discovery. Pseudo-natural products (PNPs) are de novo combinations of NP fragments to target biologically relevant chemical space not covered by NPs. We describe the design and synthesis of apoxidoles, a novel pseudo-NP class, whereby indole- and tetrahydropyridine fragments are linked in monopodal connectivity not found in nature. Apoxidoles are efficiently accessible by an enantioselective [4+2] annulation reaction. Biological evaluation revealed that apoxidoles define a new potent type IV inhibitor chemotype of indoleamine 2,3-dioxygenase 1 (IDO1), a heme-containing enzyme considered a target for the treatment of neurodegeneration, autoimmunity and cancer. Apoxidoles target apo-IDO1, prevent heme binding and induce unique amino acid positioning as revealed by crystal structure analysis. Novel type IV apo-IDO1 inhibitors are in high demand, and apoxidoles may provide new opportunities for chemical biology and medicinal chemistry research.


Assuntos
Produtos Biológicos , Aminoácidos , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Inibidores Enzimáticos/química , Heme , Indolamina-Pirrol 2,3,-Dioxigenase , Indóis , Pirrolidinas , Relação Estrutura-Atividade
11.
Int J Mol Sci ; 22(16)2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34445728

RESUMO

Phytopathogens, such as biotrophs, hemibiotrophs and necrotrophs, pose serious stress on the development of their host plants, compromising their yields. Plants are in constant interaction with such phytopathogens and hence are vulnerable to their attack. In order to counter these attacks, plants need to develop immunity against them. Consequently, plants have developed strategies of recognizing and countering pathogenesis through pattern-triggered immunity (PTI) and effector-triggered immunity (ETI). Pathogen perception and surveillance is mediated through receptor proteins that trigger signal transduction, initiated in the cytoplasm or at the plasma membrane (PM) surfaces. Plant hosts possess microbe-associated molecular patterns (P/MAMPs), which trigger a complex set of mechanisms through the pattern recognition receptors (PRRs) and resistance (R) genes. These interactions lead to the stimulation of cytoplasmic kinases by many phosphorylating proteins that may also be transcription factors. Furthermore, phytohormones, such as salicylic acid, jasmonic acid and ethylene, are also effective in triggering defense responses. Closure of stomata, limiting the transfer of nutrients through apoplast and symplastic movements, production of antimicrobial compounds, programmed cell death (PCD) are some of the primary defense-related mechanisms. The current article highlights the molecular processes involved in plant innate immunity (PII) and discusses the most recent and plausible scientific interventions that could be useful in augmenting PII.


Assuntos
Interações Hospedeiro-Patógeno , Imunidade Inata , Plantas/imunologia , Transdução de Sinais , Cromatina/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Plantas/metabolismo
12.
J Pak Med Assoc ; 71(8): 1980-1983, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34418014

RESUMO

OBJECTIVE: To compare efficacy of intravenous paracetamol and fentanyl for intra-operative and post-operative analgesia in patients undergoing rigid hysteroscopy. METHOD: The prospective randomised control trial was conducted at Aga Khan University Hospital, Karachi, from October 2016 to June 2017, and comprised patients aged 18-65 years with American Society of Anesthesiologists grade I or II undergoing hysteroscopy who were randomised into paracetamol group P and fentanyl group F. Anaesthesia induction technique was standardised and analgesia in group P was paracetamol 15mg/Kg administered 15-30 minutes pre-surgery, and in group F, it was fentanyl 2mcg/kg administered at induction of anaesthesia. Intra-operative pain was assessed by changes in heart rate, systolic, diastolic and mean arterial blood pressure, and post-operative pain was assessed using the visual analogue scale. Data was analysed using SPSS 19. RESULTS: Of the 60 patients, there were 30(50%) in each of the two groups. Baseline parameters were similar in the groups except for age differences (p<0.011). In group P, mean systolic blood pressure at 10,15, 20, 25 and 30 minutes, mean diastolic blood pressure at 20, 25 minutes, and mean arterial blood pressure at 20 minutes were statistically significant (p<0.05) compared to group F. The mean heart rate was not significant between the groups (p>0.05). Post-operative pain scores were similar at 0, 15 and 30 minutes (p>0.05). Rescue analgesia was needed in 3(10%) patients in each group on arrival in the recovery room. CONCLUSIONS: Intravenous paracetamol offered analgesic efficacy similar to fentanyl for rigid hysteroscopy in ambulatory surgery.


Assuntos
Acetaminofen , Analgesia , Método Duplo-Cego , Feminino , Fentanila , Humanos , Histeroscopia , Gravidez , Estudos Prospectivos
13.
Opt Express ; 28(8): 11806-11821, 2020 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-32403684

RESUMO

In this paper, we demonstrate via Finite-difference time-domain (FDTD) simulations that the performance of indium-rich InxGa1-xN (x = 0.6) p-n junction thin-film solar cells is improved by incorporating an integrated structure of a 2-dimensional (2D) array of ITO nanodiscs on the top surface and a 2D array of Ag nanodiscs in the active layer above the Ag back reflector of the solar cell. The bottom Ag nanodiscs primarily enhance the absorption of longer wavelengths by coupling incident light into surface plasmon resonance (SPR) and waveguide modes. The top ITO nanodiscs enhance the middle wavelengths (400 nm to 800 nm) by coupling the incident light to photonic modes in the active layer. Thus, the integrated structure of nanodisc arrays leads to a very high absorption in the active region in broad spectral range (> 0.85 for wavelengths lying between 350 nm and 800 nm), significantly increasing the short circuit current density (Jsc) and power conversion efficiency (PCE) of the solar cell. In the proposed solar cells, the geometries of the silver and ITO nanodiscs were optimized to obtain the maximum possible values of the Jsc. The highest enhancements in Jsc and PCE of ∼25% and ∼26%, respectively, were obtained in a solar cell containing the integrated structure of ITO and Ag nanodisc arrays. Moreover, the performance of these cells was examined under oblique light incidence and it was observed that the solar cells containing the integrated structure of nanodisc arrays have a significantly larger value of Jsc when compared to the cells having no nanostructures or having only the top ITO nanodisc array or only the bottom Ag nanodisc array.

14.
BMC Anesthesiol ; 20(1): 214, 2020 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-32847522

RESUMO

BACKGROUND: Shivering is a common side effect in women having cesarean delivery (CD) under spinal anesthesia, which can be bothersome to the patient, and it can also interfere with perioperative monitoring. In several studies, the intrathecal (IT) addition of a lipophilic opioid to local anesthetics has been shown to decrease the incidence of shivering. OBJECTIVE: We performed this network meta-analysis to evaluate the effects of intrathecal lipophilic opioids in preventing the incidence of shivering in patients undergoing CD. METHODS: This review was planned according to the PRISMA for Network Meta-Analysis (PRISMA-NMA) guidelines. An English literature search of multiple electronic databases was conducted. We included randomized controlled trials (RCTs) that reported on the incidence of shivering, with study groups receiving either IT fentanyl, sufentanil, or meperidine in women undergoing CD under spinal anesthesia. Quality of the studies was assessed using the modified Oxford scoring system. Using random-effects modeling, dichotomous data were extracted and summarized using odds ratio (OR) with a 95% credible interval (CrI). Statistical analysis was conducted using R studio version 1.0.153 - Inc. RESULTS: Twenty-one studies consisting of 1433 patients (Control group: 590 patients in twenty-one studies; Fentanyl group:199 patients in seven studies; Sufentanil group: 156 patients in five studies; Meperidine group: 488 patients in ten studies) met the inclusion criteria for this systematic review investigating the effect of intrathecal lipophilic opioids in preventing the incidence of shivering in women undergoing cesarean delivery under spinal anesthesia. Methodological validity scores ranged from 3 to 7. The Bayesian mixed network estimate showed the incidence of shivering was significantly lower with IT fentanyl (pooled odds ratio (OR): 0.13; 95% credible interval (CrI): 0.04 to 0.35; P = 0.0004) and IT meperidine (OR: 0.12; 95% CrI: 0.05 to 0.29; P < 0.00001), but not with IT sufentanil (OR: 0.37; 95% CrI: 0.11 to 1.22; P = 0.23). The IT fentanyl group had a significantly lower incidence of intraoperative discomfort [Risk Ratio (RR): 0.19; 95% CI: 0.10-0.35; P < 0.00001], the IT sufentanil group had a significantly higher incidence of pruritus (RR: 6.18; 95% CI: 1.18-32.46; P = 0.03) The IT meperidine group had a significantly lower incidence of intraoperative discomfort (2.7% vs. 13.6%; RR: 0.22; 95% CI: 0.09-0.55; P = 0.001), but there was a significant increase in nausea and vomiting (IT meperidine group vs. Control group: 42.7% vs. 19.4%; RR: 2.56; 95% CI: 1.14-5.75; P = 0.02). Meta-regression analysis based on the opioid dose and quality of the study did not impact the final inference of our result. CONCLUSION: IT fentanyl significantly decreased the incidence of shivering in women undergoing CD under spinal anesthesia without increasing maternal adverse events, confirming that routine use in this patient population is a good choice. IT sufentanil did not decrease the incidence of shivering. IT meperidine decreased the incidence and severity of shivering, but its use was also associated with significant nausea and vomiting.


Assuntos
Analgésicos Opioides/administração & dosagem , Raquianestesia/métodos , Cesárea/métodos , Injeções Espinhais/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Estremecimento/efeitos dos fármacos , Analgésicos Opioides/efeitos adversos , Anestesia Obstétrica/efeitos adversos , Anestesia Obstétrica/métodos , Raquianestesia/efeitos adversos , Teorema de Bayes , Feminino , Fentanila/administração & dosagem , Fentanila/efeitos adversos , Humanos , Incidência , Injeções Espinhais/efeitos adversos , Metanálise em Rede , Náusea e Vômito Pós-Operatórios/induzido quimicamente , Gravidez , Estremecimento/fisiologia , Sufentanil/administração & dosagem , Sufentanil/efeitos adversos
15.
Environ Monit Assess ; 192(6): 368, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32415400

RESUMO

Located in the eastern lap of the Karakoram Range, the Siachen Glacier is the second longest glacier in the non-polar areas of the world. High altitude, extreme climate and frequent military conflicts on this glacier create antagonistic surroundings for conventional field studies. Although recent advancements in geodetic technique have helped in the estimation of Siachen mass budget (MB), these geodetic estimates have been observed only for short time periods ranging 6 to 10 years. Hence, current study presents a comprehensive assessment of the Siachen long-term MB (32 years) based on temperature index (TI) model. Annual surface MB variability was modelled between 1986 and 2018 by forcing daily air temperature and precipitation from multiple ground stations distributed well across accumulation/ablation zone of the glacier. Mean annual temperature lapse rate (LR) was found midway between dry adiabatic and moist adiabatic LRs. Precipitation gradient (PG) was observed remarkably different below and above 4800 m.a.s.l. glacier altitude. Furthermore, snowmelt factor (SMF) was also estimated using snow thickness and positive degree days (PDDs) information over the glacier surface. Model results showed a nearly balanced condition (- 0.02 ± 0.05 m.w.e./year) during 1986-2006 followed by an accelerated rate of mass loss during 2007-2018 (- 0.11 ± 0.05 m.w.e./year), thus making the overall condition of Siachen MB negative during the period 1986-2018 (- 0.05 ± 0.05 m.w.e./year). Comparison of modelled MB was made with few geodetic studies conducted for the Siachen Glacier at different time scales (mainly after year 2000). Further, the sensitivity of the modelled glacier-wide MB was - 0.24 m.w.e./year for a temperature rise by 1 °C, while the sensitivity towards 10% increase in precipitation was estimated to be + 0.16 m.w.e./year. A relationship of the annual MB with accumulation area ratio (AAR) and equilibrium line altitude (ELA) was also established for Siachen glacier.


Assuntos
Monitoramento Ambiental , Camada de Gelo , Modelos Teóricos , Altitude , Clima , Neve
16.
Opt Express ; 27(22): 31599-31620, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31684391

RESUMO

In this paper, we propose double junction tandem organic solar cells with PTB7:PC70BM and PDPPSDTPS:PC60BM as the polymeric active materials to cover the wide solar spectrum from 300 nm to 1150 nm. We present novel designs and finite-difference time-domain (FDTD) simulation results of plasmonic double junction tandem OSCs in which Ag nanospheres are present over the top surface of the OSC and Ag nanostars are present in the bottom subcell which substantially enhance the absorption, short circuit current density, and efficiency of the OSC as compared to the reference tandem OSCs that do not contain any nanoparticles. Different geometries of the plasmonic nanoparticles such as nanospheres and nanostars were used in the top subcell and the bottom subcell, respectively, so that the absorption in the different spectral regimes - corresponding to the bandgaps of the active layers in the two subcells (PTB7:PC70BM in the top subcell and LBG:PC60BM in the bottom subcell) - could be enhanced. The thickness of the bottom subcell active layer as well as the geometries of the plasmonic nanoparticles were optimized such that the short circuit current densities in the two subcells could be matched in the tandem OSC. An overall enhancement of 26% in the short circuit current density was achieved in a tandem OSC containing the optimized Ag nanospheres over the top surface and Ag nanostars inside the bottom subcell active layer. The presence of plasmonic nanoparticles along with the wide spectrum absorption band of the active materials in the tandem OSC leads to a typical power conversion efficiency of ∼ 15.4%, which is higher than that of a reference tandem organic solar cell (12.25%) that does not contain any nanoparticles.

17.
Chemistry ; 25(68): 15498-15503, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31518018

RESUMO

A "branching-folding" synthetic strategy that affords a range of diverse cyclic benzo-sulfonamide scaffolds is presented. Whereas different annulation reactions on common ketimine substrates build the branching phase of the scaffold synthesis, a common hydrogenative ring-expansion method, facilitated by an increase of the ring-strain during the branching phase, led to sulfonamides bearing medium-sized rings in a folding pathway. Cell painting assay was successfully employed to identify tubulin targeting sulfonamides as novel mitotic inhibitors.


Assuntos
Sulfonamidas/síntese química , Ciclização , Sulfonamidas/química
18.
Chemistry ; 25(11): 2717-2722, 2019 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-30474890

RESUMO

The first synthetic access to stable and acyclic 1,3-butadienes with two electron-withdrawing carbonyl groups and their potential to deliver new molecular scaffolds through intriguing endo-selective Diels-Alder cycloadditions are presented. The bicyclic scaffolds produced through the cycloaddition chemistry of electron-deficient dienes afforded potent Hedgehog signaling pathway inhibitors.

19.
J Sleep Res ; 28(2): e12725, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30033688

RESUMO

Knowing how an individual responds to sleep deprivation is a requirement for developing personalized fatigue management strategies. Here we describe and validate the 2B-Alert App, the first mobile application that progressively learns an individual's trait-like response to sleep deprivation in real time, to generate increasingly more accurate individualized predictions of alertness. We incorporated a Bayesian learning algorithm within the validated Unified Model of Performance to automatically and gradually adapt the model parameters to an individual after each psychomotor vigilance test. We implemented the resulting model and the psychomotor vigilance test as a smartphone application (2B-Alert App), and prospectively validated its performance in a 62-hr total sleep deprivation study in which 21 participants used the app to perform psychomotor vigilance tests every 3 hr and obtain real-time individualized predictions after each test. The temporal profiles of reaction times on the app-conducted psychomotor vigilance tests were well correlated with and as sensitive as those obtained with a previously characterized psychomotor vigilance test device. The app progressively learned each individual's trait-like response to sleep deprivation throughout the study, yielding increasingly more accurate predictions of alertness for the last 24 hr of total sleep deprivation as the number of psychomotor vigilance tests increased. After only 12 psychomotor vigilance tests, the accuracy of the model predictions was comparable to the peak accuracy obtained using all psychomotor vigilance tests. With the ability to make real-time individualized predictions of the effects of sleep deprivation on future alertness, the 2B-Alert App can be used to tailor personalized fatigue management strategies, facilitating self-management of alertness and safety in operational and non-operational settings.


Assuntos
Atenção/fisiologia , Aplicativos Móveis/tendências , Tempo de Reação/fisiologia , Vigília/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
20.
Org Biomol Chem ; 17(3): 413-431, 2019 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-30516778

RESUMO

Indole polycycles are common structural frameworks of biologically intriguing small molecules of natural and synthetic origin and therefore remain interesting and challenging synthetic targets. Cascade reactions wherein a number of reactions occur in a sequential manner in the same reaction apparatus are highly efficient chemical processes which quickly build up molecular complexity. Synthetic approaches based on cascade reactions are highly useful as they tend to avoid multiple reaction work-up steps as well as purifications of all intermediary products. Therefore, in the last decade, a number of cascade reaction based approaches to build various molecular scaffolds of biological interest have been reported. However, a relatively smaller number of cascade reaction based synthetic strategies have targeted the indole polycycles. In this article, we have summarized some interesting cascade reaction based synthesis designs leading to complex indole polycycles including some biologically intriguing and natural product inspired indole frameworks.


Assuntos
Produtos Biológicos/síntese química , Indóis/síntese química , Compostos Policíclicos/síntese química , Produtos Biológicos/química , Indóis/química , Estrutura Molecular , Compostos Policíclicos/química
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