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1.
Nature ; 633(8030): 560-566, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39261726

RESUMO

Artificial Intelligence (AI) is the domain of large resource-intensive data centres that limit access to a small community of developers1,2. Neuromorphic hardware promises greatly improved space and energy efficiency for AI but is presently only capable of low-accuracy operations, such as inferencing in neural networks3-5. Core computing tasks of signal processing, neural network training and natural language processing demand far higher computing resolution, beyond that of individual neuromorphic circuit elements6-8. Here we introduce an analog molecular memristor based on a Ru-complex of an azo-aromatic ligand with 14-bit resolution. Precise kinetic control over a transition between two thermodynamically stable molecular electronic states facilitates 16,520 distinct analog conductance levels, which can be linearly and symmetrically updated or written individually in one time step, substantially simplifying the weight update procedure over existing neuromorphic platforms3. The circuit elements are unidirectional, facilitating a selector-less 64 × 64 crossbar-based dot-product engine that enables vector-matrix multiplication, including Fourier transform, in a single time step. We achieved more than 73 dB signal-to-noise-ratio, four orders of magnitude improvement over the state-of-the-art methods9-11, while consuming 460× less energy than digital computers12,13. Accelerators leveraging these molecular crossbars could transform neuromorphic computing, extending it beyond niche applications and augmenting the core of digital electronics from the cloud to the edge12,13.


Assuntos
Redes Neurais de Computação , Cinética , Inteligência Artificial , Razão Sinal-Ruído , Ligantes , Termodinâmica , Análise de Fourier , Processamento de Sinais Assistido por Computador/instrumentação
2.
Nature ; 591(7848): 152-156, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33568810

RESUMO

Gene expression in higher eukaryotic cells orchestrates interactions between thousands of RNA-binding proteins (RBPs) and tens of thousands of RNAs1. The kinetics by which RBPs bind to and dissociate from their RNA sites are critical for the coordination of cellular RNA-protein interactions2. However, these kinetic parameters have not been experimentally measured in cells. Here we show that time-resolved RNA-protein cross-linking with a pulsed femtosecond ultraviolet laser, followed by immunoprecipitation and high-throughput sequencing, allows the determination of binding and dissociation kinetics of the RBP DAZL for thousands of individual RNA-binding sites in cells. This kinetic cross-linking and immunoprecipitation (KIN-CLIP) approach reveals that DAZL resides at individual binding sites for time periods of only seconds or shorter, whereas the binding sites remain DAZL-free for markedly longer. The data also indicate that DAZL binds to many RNAs in clusters of multiple proximal sites. The effect of DAZL on mRNA levels and ribosome association correlates with the cumulative probability of DAZL binding in these clusters. Integrating kinetic data with mRNA features quantitatively connects DAZL-RNA binding to DAZL function. Our results show how kinetic parameters for RNA-protein interactions can be measured in cells, and how these data link RBP-RNA binding to the cellular function of RBPs.


Assuntos
Proteínas de Ligação a RNA/metabolismo , RNA/metabolismo , Regiões 3' não Traduzidas/genética , Animais , Sítios de Ligação/genética , Linhagem Celular , Cinética , Lasers , Camundongos , Ligação Proteica , RNA/genética , Proteínas de Ligação a RNA/genética , Ribossomos/metabolismo
3.
Plant Physiol ; 195(4): 2551-2565, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-38739546

RESUMO

Rhamnogalacturonan II (RG-II) is a structurally complex and conserved domain of the pectin present in the primary cell walls of vascular plants. Borate cross-linking of RG-II is required for plants to grow and develop normally. Mutations that alter RG-II structure also affect cross-linking and are lethal or severely impair growth. Thus, few genes involved in RG-II synthesis have been identified. Here, we developed a method to generate viable loss-of-function Arabidopsis (Arabidopsis thaliana) mutants in callus tissue via CRISPR/Cas9-mediated gene editing. We combined this with a candidate gene approach to characterize the male gametophyte defective 2 (MGP2) gene that encodes a putative family GT29 glycosyltransferase. Plants homozygous for this mutation do not survive. We showed that in the callus mutant cell walls, RG-II does not cross-link normally because it lacks 3-deoxy-D-manno-octulosonic acid (Kdo) and thus cannot form the α-L-Rhap-(1→5)-α-D-kdop-(1→sidechain). We suggest that MGP2 encodes an inverting RG-II CMP-ß-Kdo transferase (RCKT1). Our discovery provides further insight into the role of sidechains in RG-II dimerization. Our method also provides a viable strategy for further identifying proteins involved in the biosynthesis of RG-II.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Edição de Genes , Glicosiltransferases , Pectinas , Arabidopsis/genética , Arabidopsis/metabolismo , Pectinas/metabolismo , Edição de Genes/métodos , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Glicosiltransferases/genética , Glicosiltransferases/metabolismo , Sementes/genética , Sementes/metabolismo , Sementes/crescimento & desenvolvimento , Parede Celular/metabolismo , Parede Celular/genética , Sistemas CRISPR-Cas , Mutação/genética
4.
PLoS Genet ; 18(11): e1010442, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36350833

RESUMO

Hsp90 constitutes one of the major chaperone machinery in the cell. The Hsp70 assists Hsp90 in its client maturation though the underlying basis of the Hsp70 role remains to be explored. In the present study, using S. cerevisiae strain expressing Ssa1 as sole Ssa Hsp70, we identified novel mutations in the nucleotide-binding domain of yeast Ssa1 Hsp70 (Ssa1-T175N and Ssa1-D158N) that adversely affect the maturation of Hsp90 clients v-Src and Ste11. The identified Ssa1 amino acids critical for Hsp90 function were also found to be conserved across species such as in E.coli DnaK and the constitutive Hsp70 isoform (HspA8) in humans. These mutations are distal to the C-terminus of Hsp70, that primarily mediates Hsp90 interaction through the bridge protein Sti1, and proximal to Ydj1 (Hsp40 co-chaperone of Hsp70 family) binding region. Intriguingly, we found that the bridge protein Sti1 is critical for cellular viability in cells expressing Ssa1-T175N (A1-T175N) or Ssa1-D158N (A1-D158N) as sole Ssa Hsp70. The growth defect was specific for sti1Δ, as deletion of none of the other Hsp90 co-chaperones showed lethality in A1-T175N or A1-D158N. Mass-spectrometry based whole proteome analysis of A1-T175N cells lacking Sti1 showed an altered abundance of various kinases and transcription factors suggesting compromised Hsp90 activity. Further proteomic analysis showed that pathways involved in signaling, signal transduction, and protein phosphorylation are markedly downregulated in the A1-T175N upon repressing Sti1 expression using doxycycline regulatable promoter. In contrast to Ssa1, the homologous mutations in Ssa4 (Ssa4-T175N/D158N), the stress inducible Hsp70 isoform, supported cell growth even in the absence of Sti1. Overall, our data suggest that Ydj1 competes with Hsp90 for binding to Hsp70, and thus regulates Hsp90 interaction with the nucleotide-binding domain of Hsp70. The study thus provides new insight into the Hsp70-mediated regulation of Hsp90 and broadens our understanding of the intricate complexities of the Hsp70-Hsp90 network.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Humanos , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteômica , Proteínas de Choque Térmico HSP90/genética , Proteínas de Choque Térmico HSP90/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico HSP40/metabolismo , Chaperonas Moleculares/genética , Nucleotídeos/metabolismo , Ligação Proteica , Adenosina Trifosfatases/metabolismo , MAP Quinase Quinase Quinases/metabolismo
5.
Toxicol Appl Pharmacol ; 482: 116792, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38142783

RESUMO

Radiotherapy is a common modality for cancer treatment. However, it is often associated with normal tissue toxicity in 20-80% of the patients. Radioprotectors can improve the outcome of radiotherapy by selectively protecting normal cells against radiation toxicity. In the present study, compound libraries containing 54 kinase inhibitors and 80 FDA-approved drugs were screened for radioprotection of lymphocytes using high throughput cell analysis. A second-generation FDA-approved kinase inhibitor, bosutinib, was identified as a potential radioprotector for normal cells. The radioprotective efficacy of bosutinib was evinced from a reduction in radiation induced DNA damage, caspase-3 activation, DNA fragmentation and apoptosis. Oral administration of bosutinib protected mice against whole body irradiation (WBI) induced morbidity and mortality. Bosutinib also reduced radiation induced bone-marrow aplasia and hematopoietic damage in mice exposed to 4 Gy and 6 Gy dose of WBI. Mechanistic studies revealed that the radioprotective action of bosutinib involved interaction with cellular thiols and modulation of JNK pathway. The addition of glutathione and N-acetyl cysteine significantly reduced the radioprotective efficacy of bosutinib. Moreover, bosutinib did not protect cancer cells against radiation induced toxicity. On the contrary, bosutinib per se exhibited anticancer activity against human cancer cell lines. The results highlight possible use of bosutinib as a repurposable radioprotective agent for mitigation of radiation toxicity in cancer patients undergoing radiotherapy.


Assuntos
Compostos de Anilina , Antineoplásicos , Reposicionamento de Medicamentos , Nitrilas , Quinolinas , Lesões por Radiação , Protetores contra Radiação , Animais , Humanos , Camundongos , Compostos de Anilina/farmacologia , Compostos de Anilina/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Dano ao DNA , Sistema de Sinalização das MAP Quinases , Nitrilas/farmacologia , Nitrilas/uso terapêutico , Quinolinas/farmacologia , Quinolinas/uso terapêutico , Lesões por Radiação/prevenção & controle , Protetores contra Radiação/farmacologia , Protetores contra Radiação/uso terapêutico
6.
Mol Pharm ; 21(5): 2097-2117, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38440998

RESUMO

Currently, one of the most significant and rapidly growing unmet medical challenges is the treatment of neurodegenerative diseases such as Alzheimer's disease (AD) and Parkinson's disease (PD). This challenge encompasses the imperative development of efficacious therapeutic agents and overcoming the intricacies of the blood-brain barrier for successful drug delivery. Here we focus on the delivery aspect with particular emphasis on cell-penetrating peptides (CPPs), widely used in basic and translational research as they enhance drug delivery to challenging targets such as tissue and cellular compartments and thus increase therapeutic efficacy. The combination of CPPs with nanomaterials such as nanoparticles (NPs) improves the performance, accuracy, and stability of drug delivery and enables higher drug loads. Our review presents and discusses research that utilizes CPPs, either alone or in conjugation with NPs, to mitigate the pathogenic effects of neurodegenerative diseases with particular reference to AD and PD.


Assuntos
Barreira Hematoencefálica , Peptídeos Penetradores de Células , Sistemas de Liberação de Medicamentos , Nanopartículas , Doenças Neurodegenerativas , Doença de Parkinson , Peptídeos Penetradores de Células/química , Peptídeos Penetradores de Células/administração & dosagem , Humanos , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/química , Doenças Neurodegenerativas/tratamento farmacológico , Animais , Doença de Parkinson/tratamento farmacológico , Doença de Alzheimer/tratamento farmacológico
7.
J Org Chem ; 89(1): 701-709, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38084730

RESUMO

NHC-Pd(II) pincer catalyzed oxidative amination and hydroamination of olefins is developed under solvent-free aerobic conditions. Reaction offered a temperature-controlled synthesis of (Z)-enamine and ß-amino esters to provide easy access and remarkable functional group tolerance for a variety of enamines. The developed approach renders an opportunity of scalability and flexibility, and besides this, the produced enamines can be transformed into many N-containing heterocycles, underscoring its potential usage in synthetic and pharmaceutical chemistry. Moreover, it is the first report for coupling of aniline with styrene.

8.
J Org Chem ; 89(17): 11983-11993, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39155442

RESUMO

Sustainable and highly economical iron-catalyzed chemoselective reduction of C═C of α,ß-unsaturated ketones has been established under mild reaction protocols. Water is used as a green and abundant surrogate of hydrogen and is scarcely used in organic synthetic transformations as a source of hydrogen. The developed protocol offers a broad spectrum for chemoselective transfer hydrogenation of α,ß-unsaturated ketones. Moreover, the method was found to be highly effective for aryl and ferrocenyl α,ß-unsaturated ketones consisting of one or two double bonds and with multiple functionalities. Moreover, the present method avoids prolonged reaction time, provides a wide range of substrates with excellent yield, and circumvents the tedious chromatographic workup.

9.
Pharm Res ; 2024 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-39419926

RESUMO

BACKGROUND: Favipiravir is administered orally, even against airborne RNA viruses, in a loading-dose/maintenance dose regimen. We investigated whether-(a) pulmonary delivery of favipiravir would generate high concentrations in the luminal side of the respiratory tract; and (b) avoiding first-pass metabolism by the liver by inhaled drug would generate comparable pharmacokinetics (PK) with doses significantly smaller than the oral maintenance dose. METHODS: A dry powder inhalation (DPI) of favipiravir formulated by mixing with Inhalac 400® was prepared and characterized. Inhalations of ~ 120 µg dose strength, with or without a prior oral loading dose were administered to mice. Comparator mice received human-equivalent oral doses (3 mg). Three mice per sampling time point were sacrificed and favipiravir concentrations in the blood plasma, bronchio-alveolar lavage fluid (BALF) and lung tissue homogenate determined by HPLC. RESULTS: One-compartment PK modeling of concentration-time data indicated that the area under the curve (AUC0-24 h) generated in the BALF recovered from mice receiving inhalations of ~ 1/25th of the oral dose subsequent to an oral loading dose was 86.72 ± 4.48 µg⋅mL-1⋅h. This was consistently higher than the AUC observed in the BALF of orally-dosed mice (56.71 ± 53.89 µg mL-1⋅h). In blood serum, the respective values of AUC were 321.55 ± 124.91 and 354.71 ± 99.60 µg⋅mL-1⋅h. CONCLUSION: Pulmonary delivery of significantly smaller doses of favipiravir generates meaningful drug disposition and pharmacokinetics at the site of respiratory viral infections. We provide the rationale for designing a self-administered, non-invasive, low-cost, targeted drug delivery system against airborne RNA virus infection.

10.
Bioorg Med Chem Lett ; 107: 129795, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750906

RESUMO

Chalcones are chemical scaffolds found in natural products, particularly in plants, and are considered for structural diversity in medicinal chemistry for drug development. Herein, we designed and synthesised novel acetamide derivatives of chalcone, characterizing them using 1H NMR, 13C NMR, HRMS, and IR spectroscopic methods. These derivatives were then screened against human cancer cells for cytotoxicity using the SRB assay. Among the tested derivatives, 7g, with a pyrrolidine group, exhibited better cell growth inhibition activity against triple-negative breast cancer (TNBC) cells. Further assays, including SRB, colony formation, and fluorescent dye-based microscopic analysis, confirmed that 7g significantly inhibited MDA-MB-231 cell proliferation. Furthermore, 7g promoted apoptosis by upregulating cellular reactive oxygen species (ROS) levels and disrupting mitochondrial membrane potential (MMP). Elevated expression of pro-apoptotic proteins (Bax and caspase-3) and a higher Bax/Bcl-2 ratio with downregulation of anti-apoptotic (Bcl-2) protein levels were observed in TNBC cells. The above results suggest that 7g can promote cellular death through apoptotic mechanisms in TNBC cells.


Assuntos
Acetamidas , Antineoplásicos , Apoptose , Proliferação de Células , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Relação Estrutura-Atividade , Proliferação de Células/efeitos dos fármacos , Acetamidas/farmacologia , Acetamidas/síntese química , Acetamidas/química , Apoptose/efeitos dos fármacos , Estrutura Molecular , Linhagem Celular Tumoral , Chalconas/farmacologia , Chalconas/química , Chalconas/síntese química , Relação Dose-Resposta a Droga , Chalcona/farmacologia , Chalcona/química , Chalcona/síntese química , Espécies Reativas de Oxigênio/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos
11.
Org Biomol Chem ; 22(36): 7332-7336, 2024 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-39177499

RESUMO

Azacoumarins are a relatively unexplored group of coumarin fluorophores, despite their excellent light-emitting properties. In this report, we detail the creation and production of a fluorescent probe (PYCB) based on azacoumarin for detecting H2O2. The probe utilizes a carboxy benzyl boronic pinacol ester as the recognition unit and displays a turn-on fluorescence response at 460 nm upon exposure to H2O2. The probe shows excellent sensitivity and selectivity to H2O2, with a detection limit of 0.385 µM. PYCB also exhibited strong pH stability and selectivity for H2O2 over other reactive oxygen species (ROS). Additionally, MTT assay results demonstrated the excellent biocompatibility of PYCB in MCF-7 cell lines. Fluorescence imaging of PYCB-treated MCF-7 cells revealed enhanced blue fluorescence corresponding to varying concentrations of exogenous H2O2.


Assuntos
Cumarínicos , Corantes Fluorescentes , Peróxido de Hidrogênio , Imagem Óptica , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Peróxido de Hidrogênio/análise , Humanos , Cumarínicos/química , Cumarínicos/síntese química , Células MCF-7 , Estrutura Molecular , Sobrevivência Celular/efeitos dos fármacos , Compostos Aza/química , Compostos Aza/síntese química
12.
Org Biomol Chem ; 22(34): 7039-7051, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39145468

RESUMO

A transition metal-free approach has been devised for the synthesis of a variety of bis(indolyl)propyne (BIP) derivatives. The strategy involves an iodine-catalyzed cascade condensation of α,ß-unsaturated acetylenic aldehydes with diversely substituted indoles. The strategy was applicable to gram scale synthesis and a library of 50 molecules, which were afforded in good to excellent yields (up to 96%), was developed. The salient features of the reaction involve the synthesis of indole based privileged scaffolds in a short reaction time under transition metal-free conditions, with a wide substrate scope and excellent yields under ambient conditions.

13.
Epidemiol Infect ; 152: e18, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38204334

RESUMO

Legionellosis is a disease caused by the bacterium Legionella that most commonly presents as Legionnaires' disease (LD), a severe form of pneumonia. From 2015 to 2019, an average of 438 LD cases per year were reported in Canada. However, it is believed that the actual number of cases is much higher, since LD may be underdiagnosed and underreported. The purpose of this study was to develop an estimate of the true incidence of illnesses, hospitalizations, and deaths associated with LD in Canada. Values were derived using a stochastic model, based on Canadian surveillance data from 2015 to 2019, which were scaled up to account for underdiagnosis and underreporting. Overall, there were an estimated 1,113 (90% CrI: 737-1,730) illnesses, 1,008 (90% CrI: 271-2,244) hospitalizations, and 34 (90% CrI: 4-86) deaths due to domestically acquired waterborne LD annually in Canada from 2015 to 2019. It was further estimated that only 36% of illnesses and 39% of hospitalizations and deaths were captured in surveillance, and that 22% of illnesses were caused by Legionella serogroups and species other than Legionella pneumophila serogroup 1 (non-Lp1). This study highlights the true burden and areas for improvement in Canada's surveillance and detection of LD.


Assuntos
Legionella pneumophila , Legionella , Legionelose , Doença dos Legionários , Humanos , Doença dos Legionários/epidemiologia , Doença dos Legionários/microbiologia , Canadá/epidemiologia , Legionelose/epidemiologia , Legionelose/microbiologia , Efeitos Psicossociais da Doença
14.
BMC Geriatr ; 24(1): 20, 2024 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-38178009

RESUMO

BACKGROUND: Nepal's low fertility rate and increasing life expectancy have resulted in a burgeoning older population. For millennia, filial piety shaped family cohesion and helped Nepali older adults achieve positive outcomes, but recently, it has been eroding. Furthermore, there are not enough institutional support options or alternatives to family-based care to deal with the biosocial needs of older adults. This study explored the association between family support and self-rated health among Nepali older adults. METHODS: A community-based cross-sectional survey in eastern Nepal's two districts, Sunsari and Morang, interviewed 847 older adults (≥ 60 years). The final analytical sample was 844. Participants were asked whether they received assistance with various aspects of daily life and activities of daily living from their families. Multivariable logistic regression examined the association between family support and self-rated health. RESULTS: Participants who received support with various aspects of daily life had 43% higher odds of good health, but after adjusting for control variables, the result only approached statistical significance (p = 0.087). Those who received family assistance with activities of daily living had nearly four times higher odds (OR: 3.93; 95% CI: 2.58 - 5.98) of reporting good health than participants who lacked this support. CONCLUSIONS: Given the important role of family support in Nepali older adults' health, government programs and policies should create a conducive environment to foster family-based care until more comprehensive policies for older adults' care can be put into effect. The results of this study can also help shape the global aging environment by highlighting the need for family support in older care, particularly in low-income nations with declining traditional care systems and weak social security policies.


Assuntos
Atividades Cotidianas , Apoio Familiar , Humanos , Idoso , Estudos Transversais , Nepal/epidemiologia , Envelhecimento
15.
Phytother Res ; 38(3): 1555-1573, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38281735

RESUMO

Anti-inflammatory and immune suppressive agents are required to moderate hyper-activation of lymphocytes under disease conditions or organ transplantation. However, selective disruption of mitochondrial redox has not been evaluated as a therapeutic strategy for suppression of T-cell-mediated pathologies. Using mitochondrial targeted curcumin (MitoC), we studied the effect of mitochondrial redox modulation on T-cell responses by flow cytometry, transmission electron microscopy, transcriptomics, and proteomics, and the role of Nrf2 was studied using Nrf2- /- mice. MitoC decreased mitochondrial TrxR activity, enhanced mitochondrial ROS (mROS) production, depleted mitochondrial glutathione, and suppressed activation-induced increase in mitochondrial biomass. This led to suppression of T-cell responses and metabolic reprogramming towards Treg differentiation. MitoC induced nuclear translocation and DNA binding of Nrf2, leading to upregulation of Nrf2-dependent genes and proteins. MitoC-mediated changes in mitochondrial redox and modulation of T-cell responses are abolished in Nrf2- /- mice. Restoration of mitochondrial thiols abrogated inhibition of T-cell responses. MitoC suppressed alloantigen-induced lymphoblast formation, inflammatory cytokines, morbidity, and mortality in acute graft-versus-host disease mice. Disruption of mitochondrial thiols but not mROS increase inculcates an Nrf2-dependent immune-suppressive disposition in T cells for the propitious treatment of graft-versus-host disease.


Assuntos
Curcumina , Curcumina/análogos & derivados , Doença Enxerto-Hospedeiro , Animais , Camundongos , Curcumina/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Linfócitos T , Modelos Animais de Doenças , Doença Enxerto-Hospedeiro/metabolismo , Doença Enxerto-Hospedeiro/patologia , Compostos de Sulfidrila/metabolismo , Compostos de Sulfidrila/farmacologia
16.
J Clin Monit Comput ; 38(5): 1101-1115, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39150462

RESUMO

Blood velocities measured by Transcranial Doppler (TCD) are dependent on the angle between the incident ultrasound beam and the direction of blood flow (known as the Doppler angle). However, when TCD examinations are performed without imaging the Doppler angle for each vessel segment is not known. We have measured Doppler angles in the basal cerebral arteries examined with TCD using three-dimensional (3D) vessel models generated from computed tomography angiography (CTA) scans. This approach produces angle statistics that are not accessible during non-imaging TCD studies. We created 3D models of the basal cerebral arteries for 24 vasospasm patients. Standard acoustic windows were mapped to the specific anatomy of each patient. Virtual ultrasound transmit beams were generated that originated from the acoustic window and intersected the centerline of each arterial segment. Doppler angle measurements were calculated and compiled for each vessel segment. Doppler angles were smallest for the middle cerebral artery M1 segment (median 24.6°) and ophthalmic artery (median 25.0°), and largest for the anterior cerebral artery A2 segment (median 76.4°) and posterior cerebral artery P2 segment (median 75.8°). The ophthalmic artery had the highest proportion of Doppler angles that were less than 60° (99%) while the anterior cerebral artery A2 segment had the lowest proportion of Doppler angles that were less than 60° (10%). These angle measurements indicate the expected deviation between measured and true velocities in the cerebral arteries, highlighting specific segments that may be prone to underestimation of velocity.


Assuntos
Circulação Cerebrovascular , Angiografia por Tomografia Computadorizada , Imageamento Tridimensional , Ultrassonografia Doppler Transcraniana , Humanos , Ultrassonografia Doppler Transcraniana/métodos , Angiografia por Tomografia Computadorizada/métodos , Imageamento Tridimensional/métodos , Feminino , Masculino , Velocidade do Fluxo Sanguíneo , Artérias Cerebrais/diagnóstico por imagem , Pessoa de Meia-Idade , Vasoespasmo Intracraniano/diagnóstico por imagem , Idoso , Adulto , Angiografia Cerebral/métodos , Artéria Oftálmica/diagnóstico por imagem
17.
Artigo em Inglês | MEDLINE | ID: mdl-38497194

RESUMO

Transbronchial lung cryobiopsy (TBLC) with flexible bronchoscope represents an encouraging modality to obtain a larger size specimen without crush artifact, and a higher diagnostic yield in patients with diffuse parenchymal lung lesions/diseases as compared to conventional transbronchial lung biopsy, and fewer complications as opposed to surgical lung biopsy. Artificial airway is preferred as it provides better airway protection in cases of severe bleeding. Although various researchers have published data on different modalities, the data is not sufficient to standardize a single technique. This study describes the procedural technique, safety, and yield of TBLC using a flexible bronchoscope with an endobronchial blocker. We performed a retrospective analysis of 100 consecutive patients who underwent TBLC using flexible bronchoscopy from May 2018 to June 2022. TBLC samples were obtained under moderate sedation without the use of artificial airway or fluoroscopy. Among the 100 patients, the majority were male (63%). The mean age of the enrolled patients was 44.43±15.92 years. The predominant diagnoses in our study were hypersensitivity pneumonitis (27%), followed by sarcoidosis (12%) and tuberculosis (10%). We obtained alveolated lung tissue in 90 out of 100 cases with a median biopsy size of 5 mm (in greatest dimension, interquartile range 5-4 mm), resulting in a specific histopathological diagnosis in 82 cases. The most frequent complications were bleeding and pneumothorax (13%). Mild bleeding occurred in 58% of the patients, and moderate bleeding occurred in 20% of the patients. There was no episode of severe/life-threatening bleeding. None of the patients required intensive care unit admission or endotracheal intubation. In conclusion, the use of TBLC through flexible bronchoscopy with an endobronchial blocker emerges as a minimally invasive, secure, time-efficient, and readily reproducible technique. Significantly, this procedure can be seamlessly executed in the bronchoscopy suite, eliminating the requirement for an artificial airway or general anesthesia.

18.
AAPS PharmSciTech ; 25(1): 14, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38191830

RESUMO

Vemurafenib (VMF) is a practically insoluble (< 0.1 µg/mL) and least bioavailable (1%) drug. To enhance its oral bioavailability and solubility, we formulated a reliable self-nano emulsifying drug delivery system (SNEDDS). A Quality by Design (QbD) approach was used to optimize the ratio of Capryol 90, Tween 80, and Transcutol HP. VMF-loaded SNEDDS was characterized for its size, polydispersity index (PDI), zeta potential, drug content, and transmittance. The in vitro release profile of the drug loaded in SNEDDS was compared to the free drug in two media, pH 6.8 and 1.2, and the data obtained were analyzed with different mathematical models. A reverse-phase ultra-pressure liquid chromatography (UPLC) technique with high sensitivity and selectivity was developed and validated for the quantification of VMF in analytical and bioanalytical samples. Dissolution efficiency for SNEDDS was estimated using different models, which proved that the developed novel SNEDDS formulation had a better in vitro dissolution profile than the free drug. A 2.13-fold enhanced oral bioavailability of VMF-loaded SNEDDS compared to the free drug demonstrates the superiority of the developed formulation. This work thus presents an overview of VMF-loaded SNEDDS as a promising alternative to improve the oral bioavailability of the drug.


Assuntos
Cromatografia de Fase Reversa , Polissorbatos , Disponibilidade Biológica , Vemurafenib , Solubilidade
19.
Trop Anim Health Prod ; 56(2): 91, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38430331

RESUMO

Salmonella species (spp) is the most important gastrointestinal pathogen present ubiquitously. Non typhoidal Salmonella (NTS) is commonly associated with gastroenteritis in humans. Layer birds once get infection with NTS, can become persistently infected with Salmonella Typhimurium and intermittently shed the bacteria. It results in a high risk of potential exposure of eggs to the bacteria. The current study was conducted to determine the serotype diversity, presence of virulence genes, antibiotic resistance pattern, and genes of NTS from poultry enteritis. Out of 151 intestinal swabs from poultry total 118 NTS were isolated, which were characterized serologically as S. Typhimurium (51 strains), S. Weltevreden (57 strains) and untypable (10 strains). Most effective antibiotics were amikacin, gentamycin and ceftriaxone (33.05%) followed by ampicillin, azithromycin and ciprofloxacin (16.69%), co-trimoxazole (13.55%), and tetracycline (6.78%). Multidrug resistance recorded in 17.70% (N = 21/118) strains. Antimicrobial-resistant genes i.e. blaTEM, blaSHV, blaCTX-M, tet(A), tet(B), tet(C), sul1, sul2, sul3. blaTEM and tet(A) were present in 95% (20/21). Eleven virulence genes i.e. invA, hilA, sivH, tolC, agfA, lpfA, spaN, pagC, spiA, iroN and fliC 2 were present in all the 30 isolates. While, sopE was present in only 2 isolates, NTS strains with characteristics of pathogenicity and multidrug resistance from poultry enteritis were detected. Multidrug resistance showed the necessity of prudent use of antibiotics in the poultry industry.


Assuntos
Enterite , Aves Domésticas , Animais , Humanos , Virulência/genética , Óvulo , Enterite/epidemiologia , Enterite/veterinária , Salmonella , Antibacterianos/farmacologia , Índia/epidemiologia , Resistência Microbiana a Medicamentos
20.
Trop Anim Health Prod ; 56(7): 226, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39093442

RESUMO

Since 2019, Lumpy skin disease (LSD) has suddenly spread in many Asian countries, including India. LSD primarily occurs in cattle. However, recent LSD outbreaks in India have also revealed significant morbidity and production losses in buffaloes. This has raised concerns about the role of buffaloes in the epidemiology and transmission of LSD and necessitates the inclusion of buffaloes in the mass vaccination program for the prevention and control of the disease in the country. However, there is no significant data on the immune response in buffaloes following vaccination with the LSD vaccine. In this study, we evaluated antibody- and cell-mediated immune responses following vaccination with a newly developed live-attenuated LSD vaccine (Lumpi-ProVacInd). The detectable amount of anti-LSDV antibodies was observed at 1-2 months following vaccination, with a peak antibody titer at 3 months. Upon stimulation of the peripheral blood mononuclear cells (PBMCs) with the UV-inactivated LSDV antigen, there was a significant increase in CD8 + T cell counts in vaccinated animals as compared to the unvaccinated animals. Besides, vaccinated animals also showed a significant increase in IFN-γ levels upon antigenic stimulation of their PBMCs with LSDV antigen. In conclusion, the buffaloes also mount a potent antibody- and cell-mediated immune response following vaccination with Lumpi-ProVacInd.


Assuntos
Búfalos , Doença Nodular Cutânea , Vírus da Doença Nodular Cutânea , Vacinas Atenuadas , Vacinas Virais , Animais , Búfalos/imunologia , Doença Nodular Cutânea/prevenção & controle , Doença Nodular Cutânea/imunologia , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/imunologia , Vírus da Doença Nodular Cutânea/imunologia , Vacinas Virais/administração & dosagem , Vacinas Virais/imunologia , Índia , Imunidade Celular , Anticorpos Antivirais/sangue , Vacinação/veterinária , Leucócitos Mononucleares/imunologia , Feminino
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