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1.
Nature ; 629(8010): 80-85, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38693414

RESUMO

Building a fault-tolerant quantum computer will require vast numbers of physical qubits. For qubit technologies based on solid-state electronic devices1-3, integrating millions of qubits in a single processor will require device fabrication to reach a scale comparable to that of the modern complementary metal-oxide-semiconductor (CMOS) industry. Equally important, the scale of cryogenic device testing must keep pace to enable efficient device screening and to improve statistical metrics such as qubit yield and voltage variation. Spin qubits1,4,5 based on electrons in Si have shown impressive control fidelities6-9 but have historically been challenged by yield and process variation10-12. Here we present a testing process using a cryogenic 300-mm wafer prober13 to collect high-volume data on the performance of hundreds of industry-manufactured spin qubit devices at 1.6 K. This testing method provides fast feedback to enable optimization of the CMOS-compatible fabrication process, leading to high yield and low process variation. Using this system, we automate measurements of the operating point of spin qubits and investigate the transitions of single electrons across full wafers. We analyse the random variation in single-electron operating voltages and find that the optimized fabrication process leads to low levels of disorder at the 300-mm scale. Together, these results demonstrate the advances that can be achieved through the application of CMOS-industry techniques to the fabrication and measurement of spin qubit devices.

2.
Immunity ; 49(4): 666-677.e6, 2018 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-30291029

RESUMO

Regulatory T (Treg) cell responses and apoptotic cell clearance (efferocytosis) represent critical arms of the inflammation resolution response. We sought to determine whether these processes might be linked through Treg-cell-mediated enhancement of efferocytosis. In zymosan-induced peritonitis and lipopolysaccharide-induced lung injury, Treg cells increased early in resolution, and Treg cell depletion decreased efferocytosis. In advanced atherosclerosis, where defective efferocytosis drives disease progression, Treg cell expansion improved efferocytosis. Mechanistic studies revealed the following sequence: (1) Treg cells secreted interleukin-13 (IL-13), which stimulated IL-10 production in macrophages; (2) autocrine-paracrine signaling by IL-10 induced Vav1 in macrophages; and (3) Vav1 activated Rac1 to promote apoptotic cell engulfment. In summary, Treg cells promote macrophage efferocytosis during inflammation resolution via a transcellular signaling pathway that enhances apoptotic cell internalization. These findings suggest an expanded role of Treg cells in inflammation resolution and provide a mechanistic basis for Treg-cell-enhancement strategies for non-resolving inflammatory diseases.


Assuntos
Apoptose/imunologia , Inflamação/imunologia , Macrófagos/imunologia , Fagocitose/imunologia , Linfócitos T Reguladores/imunologia , Animais , Linhagem Celular , Células Cultivadas , Humanos , Inflamação/metabolismo , Interleucina-10/genética , Interleucina-10/imunologia , Interleucina-10/metabolismo , Interleucina-13/genética , Interleucina-13/imunologia , Interleucina-13/metabolismo , Células Jurkat , Lipopolissacarídeos , Pneumopatias/induzido quimicamente , Pneumopatias/imunologia , Pneumopatias/metabolismo , Macrófagos/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Peritonite/induzido quimicamente , Peritonite/imunologia , Peritonite/metabolismo , Linfócitos T Reguladores/metabolismo , Zimosan
3.
Development ; 149(14)2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35781558

RESUMO

Formation of highly unique and complex facial structures is controlled by genetic programs that are responsible for the precise coordination of three-dimensional tissue morphogenesis. However, the underlying mechanisms governing these processes remain poorly understood. We combined mouse genetic and genomic approaches to define the mechanisms underlying normal and defective midfacial morphogenesis. Conditional inactivation of the Wnt secretion protein Wls in Pax3-expressing lineage cells disrupted frontonasal primordial patterning, cell survival and directional outgrowth, resulting in altered facial structures, including midfacial hypoplasia and midline facial clefts. Single-cell RNA sequencing revealed unique transcriptomic atlases of mesenchymal subpopulations in the midfacial primordia, which are disrupted in the conditional Wls mutants. Differentially expressed genes and cis-regulatory sequence analyses uncovered that Wls modulates and integrates a core gene regulatory network, consisting of key midfacial regulatory transcription factors (including Msx1, Pax3 and Pax7) and their downstream targets (including Wnt, Shh, Tgfß and retinoic acid signaling components), in a mesenchymal subpopulation of the medial nasal prominences that is responsible for midline facial formation and fusion. These results reveal fundamental mechanisms underlying mammalian midfacial morphogenesis and related defects at single-cell resolution.


Assuntos
Redes Reguladoras de Genes , Transcriptoma , Animais , Face , Mamíferos/genética , Camundongos , Morfogênese/genética , Transcriptoma/genética , Proteínas Wnt/metabolismo
5.
Mol Psychiatry ; 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38486047

RESUMO

Recent studies have sparked renewed interest in the therapeutic potential of psychedelics for treating depression and other mental health conditions. Simultaneously, the novel psychoactive substances (NPS) phenomenon, with a huge number of NPS emerging constantly, has changed remarkably the illicit drug market, being their scientific evaluation an urgent need. Thus, this study aims to elucidate the impact of amino-terminal modifications to the 5-MeO-DMT molecule on its interactions with serotonin receptors and transporters, as well as its psychoactive and thermoregulatory properties. Our findings demonstrated, using radioligand binding methodologies, that all examined 5-MeO-tryptamines exhibited selectivity for 5-HT1AR over 5-HT2AR. In fact, computational docking analyses predicted a better interaction in the 5-HT1AR binding pocket compared to 5-HT2AR. Our investigation also proved the interaction of these compounds with SERT, revealing that the molecular size of the amino group significantly influenced their affinity. Subsequent experiments involving serotonin uptake, electrophysiology, and superfusion release assays confirmed 5-MeO-pyr-T as the most potent partial 5-HT releaser tested. All tested tryptamines elicited, to some degree, the head twitch response (HTR) in mice, indicative of a potential hallucinogenic effect and mainly mediated by 5-HT2AR activation. However, 5-HT1AR was also shown to be implicated in the hallucinogenic effect, and its activation attenuated the HTR. In fact, tryptamines that produced a higher hypothermic response, mediated by 5-HT1AR, tended to exhibit a lower hallucinogenic effect, highlighting the opposite role of both 5-HT receptors. Moreover, although some 5-MeO-tryptamines elicited very low HTR, they still act as potent 5-HT2AR agonists. In summary, this research offers a comprehensive understanding of the psychopharmacological profile of various amino-substituted 5-MeO-tryptamines, keeping structural aspects in focus and accumulating valuable data in the frame of NPS. Moreover, the unique characteristics of some 5-MeO-tryptamines render them intriguing molecules as mixed-action drugs and provide insight within the search of non-hallucinogenic but 5-HT2AR ligands as therapeutical agents.

6.
PLoS Comput Biol ; 20(4): e1012031, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38669236

RESUMO

With the generation of spatially resolved transcriptomics of microbial biofilms, computational tools can be used to integrate this data to elucidate the multi-scale mechanisms controlling heterogeneous biofilm metabolism. This work presents a Multi-scale model of Metabolism In Cellular Systems (MiMICS) which is a computational framework that couples a genome-scale metabolic network reconstruction (GENRE) with Hybrid Automata Library (HAL), an existing agent-based model and reaction-diffusion model platform. A key feature of MiMICS is the ability to incorporate multiple -omics-guided metabolic models, which can represent unique metabolic states that yield different metabolic parameter values passed to the extracellular models. We used MiMICS to simulate Pseudomonas aeruginosa regulation of denitrification and oxidative stress metabolism in hypoxic and nitric oxide (NO) biofilm microenvironments. Integration of P. aeruginosa PA14 biofilm spatial transcriptomic data into a P. aeruginosa PA14 GENRE generated four PA14 metabolic model states that were input into MiMICS. Characteristic of aerobic, denitrification, and oxidative stress metabolism, the four metabolic model states predicted different oxygen, nitrate, and NO exchange fluxes that were passed as inputs to update the agent's local metabolite concentrations in the extracellular reaction-diffusion model. Individual bacterial agents chose a PA14 metabolic model state based on a combination of stochastic rules, and agents sensing local oxygen and NO. Transcriptome-guided MiMICS predictions suggested microscale denitrification and oxidative stress metabolic heterogeneity emerged due to local variability in the NO biofilm microenvironment. MiMICS accurately predicted the biofilm's spatial relationships between denitrification, oxidative stress, and central carbon metabolism. As simulated cells responded to extracellular NO, MiMICS revealed dynamics of cell populations heterogeneously upregulating reactions in the denitrification pathway, which may function to maintain NO levels within non-toxic ranges. We demonstrated that MiMICS is a valuable computational tool to incorporate multiple -omics-guided metabolic models to mechanistically map heterogeneous microbial metabolic states to the biofilm microenvironment.


Assuntos
Biofilmes , Modelos Biológicos , Estresse Oxidativo , Pseudomonas aeruginosa , Transcriptoma , Biofilmes/crescimento & desenvolvimento , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Pseudomonas aeruginosa/fisiologia , Estresse Oxidativo/fisiologia , Transcriptoma/genética , Biologia Computacional , Redes e Vias Metabólicas/genética , Óxido Nítrico/metabolismo , Simulação por Computador , Desnitrificação
7.
PLoS Pathog ; 18(12): e1010952, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36480516

RESUMO

Antibiotic resistance is a leading cause of hospitalization and death worldwide. Heavy metals such as arsenic have been shown to drive co-selection of antibiotic resistance, suggesting arsenic-contaminated drinking water is a risk factor for antibiotic resistance carriage. This study aimed to determine the prevalence and abundance of antibiotic-resistant Escherichia coli (AR-Ec) among people and drinking water in high (Hajiganj, >100 µg/L) and low arsenic-contaminated (Matlab, <20 µg/L) areas in Bangladesh. Drinking water and stool from mothers and their children (<1 year) were collected from 50 households per area. AR-Ec was detected via selective culture plating and isolates were tested for antibiotic resistance, arsenic resistance, and diarrheagenic genes by PCR. Whole-genome sequencing (WGS) analysis was done for 30 E. coli isolates from 10 households. Prevalence of AR-Ec was significantly higher in water in Hajiganj (48%) compared to water in Matlab (22%, p <0.05) and among children in Hajiganj (94%) compared to children in Matlab (76%, p <0.05), but not among mothers. A significantly higher proportion of E. coli isolates from Hajiganj were multidrug-resistant (83%) compared to isolates from Matlab (71%, p <0.05). Co-resistance to arsenic and multiple antibiotics (MAR index >0.2) was observed in a higher proportion of water (78%) and child stool (100%) isolates in Hajiganj than in water (57%) and children (89%) in Matlab (p <0.05). The odds of arsenic-resistant bacteria being resistant to third-generation cephalosporin antibiotics were higher compared to arsenic-sensitive bacteria (odds ratios, OR 1.2-7.0, p <0.01). WGS-based phylogenetic analysis of E. coli isolates did not reveal any clustering based on arsenic exposure and no significant difference in resistome was found among the isolates between the two areas. The positive association detected between arsenic exposure and antibiotic resistance carriage among children in arsenic-affected areas in Bangladesh is an important public health concern that warrants redoubling efforts to reduce arsenic exposure.


Assuntos
Arsênio , Água Potável , Criança , Humanos , Escherichia coli/genética , Antibacterianos/farmacologia , Arsênio/farmacologia , Filogenia
8.
J Pediatr ; 269: 114001, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38432296

RESUMO

OBJECTIVE: To assess the relative risk of mortality in infants born preterm and small for gestational age (SGA) during the first and second months of life in rural Bangladesh. STUDY DESIGN: We analyzed data from a cohort of pregnant women and their babies in Sylhet, Bangladesh, assembled between 2011 and 2014. Community health workers visited enrolled babies up to 10 times from birth to age 59 days. Survival status was recorded at each visit. Gestational age was estimated from mother's reported last menstrual period. Birth weights were measured within 72 hours of delivery. SGA was defined using the INTERGROWTH-21st standard. We estimated unadjusted and adjusted hazard ratios (HRs) and corresponding 95% CIs for babies born preterm and SGA separately for the first and second month of life using bivariate and multivariable weighted Cox regression models. RESULTS: The analysis included 17 643 singleton live birth babies. Compared with infants born at term-appropriate for gestational age, in both unadjusted and adjusted analyses, infants born preterm-SGA had the greatest risk of death in the first (HR 13.25, 95% CI 8.65-20.31; adjusted HR 12.05, 95% CI 7.82-18.57) and second month of life (HR 4.65, 95% CI 1.93-11.23; adjusted HR 4.1, 95% CI 1.66-10.15), followed by infants born preterm-appropriate for gestational age and term-SGA. CONCLUSIONS: The risk of mortality in infants born preterm and/or SGA is increased and extends through the second month of life. Appropriate interventions to prevent and manage complications caused by prematurity and SGA could improve survival during and beyond the neonatal period.


Assuntos
Mortalidade Infantil , Recém-Nascido Prematuro , Recém-Nascido Pequeno para a Idade Gestacional , População Rural , Humanos , Bangladesh/epidemiologia , Recém-Nascido , Feminino , Estudos Prospectivos , População Rural/estatística & dados numéricos , Masculino , Lactente , Adulto , Gravidez , Idade Gestacional , Nascimento Prematuro/epidemiologia , Adulto Jovem , Estudos de Coortes
9.
J Autoimmun ; 147: 103265, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38838452

RESUMO

OBJECTIVES: The aim of the study was to establish an international multicenter registry to collect data on patients with Multisystem Inflammatory Syndrome in Children (MIS-C), in order to highlight a relationship between clinical presentation, age of onset and geographical distribution on the clinical outcome. STUDY DESIGN: Multicenter retrospective study involving different international societies for rare immunological disorders.1009 patients diagnosed with MIS-C between March and September 2022, from 48 centers and 22 countries were collected. Five age groups (<1, 1-4, 5-11, 12-16, >16 years) and four geographic macro-areas, Western Europe, Central-Eastern Europe, Latin America, Asian-African resource-limited countries (LRC), were identified. RESULTS: Time to referral was significantly higher in LRC. Intensive anti-inflammatory treatment, including biologics, respiratory support and mechanic ventilation were more frequently used in older children and in European countries. The mortality rate was higher in very young children (<1 year), in older patients (>16 years of age) and in LRC. Multivariate analysis identified the residence in LRC, presence of severe cardiac involvement, renal hypertension, lymphopenia and non-use of heparin prophylaxis, as the factors most strongly associated with unfavorable outcomes. CONCLUSIONS: The stratification of patients by age and geographic macro-area provided insights into the clinical presentation, treatment and outcome of MIS-C. The mortality and sequelae rates exhibited a correlation with the age and geographical areas. Patients admitted and treated in LRC displayed more severe outcomes, possibly due to delays in hospital admission and limited access to biologic drugs and to intensive care facilities.

10.
Cytokine ; 175: 156499, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38199085

RESUMO

BACKGROUND: Preeclampsia is a serious medical condition that significantly affects expectant mothers. Growing research showed an inconsistent association between TNF-alfa rs1800629 polymorphism and preeclampsia. The current meta-analysis was aimed at examining the potential impact of rs1800629 variant on preeclampsia. METHODS: The Cochrane Library, Google Scholar, PubMed, EMBASE, Web of Science, and other databases were searched extensively to locate and select articles up to October 30, 2023. The PRISMA 2020 recommendations were followed to perform this study. Data analysis was done by using Comprehensive Meta analysis (v 3). RESULTS: We have included 32 articles containing 35 studies with 3,883 patients and 5,821 controls for qualitative and quantitative data analysis. We found a strong relationship between rs1800629 variant with the increased preeclampsia risk in co-dominant model 1 (OR = 1.33, p = 0.019), co-dominant model 2 (OR = 1.43, p = 0.014), dominant model (OR = 1.25, p = 0.044), over-dominant model (OR = 1.31, p = 0.021), and allelic model (OR = 1.24, p = 0.018). This study also revealed a significantly higher risk among the Asian population in the dominant (OR = 2.31, p = 0.036) and allelic model (OR = 2.02, p = 0.028). For the Caucasian population, an increased association between the rs1800629 variant and preeclampsia risk was reported in co-dominant model 1 (OR = 1.37, p = 0.011), co-dominant model 2 (OR = 1.77, p = 0.007), dominant model (OR = 1.32, p = 0.030), recessive (OR = 1.50, p = 0.047), over-dominant (OR = 1.34, p = 0.009), and allelic model (OR = 1.32, p = 0.004). Though our study showed the protective link of the TNF-alfa polymorphism to the preeclampsia risk among the Black population, no significant outcomes were observed in any genetic models (p > 0.05). CONCLUSION: Overall, the present meta-analysis explored a consistent linkage of the TNF-alfa rs1800629 variant to the preeclampsia risk in different ethnic groups. Additional research is required to confirm the precise relationship between the rs1800629 variant and preeclampsia risk.


Assuntos
Predisposição Genética para Doença , Pré-Eclâmpsia , Fator de Necrose Tumoral alfa , Feminino , Humanos , Etnicidade , Polimorfismo de Nucleotídeo Único , Pré-Eclâmpsia/genética , Fator de Necrose Tumoral alfa/genética
11.
BMC Cancer ; 24(1): 660, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816694

RESUMO

BACKGROUND: Breast and cervical cancer are the two leading cancers in terms of incidence and mortality. Previous studies reported different interleukins, including interleukin-17A (IL-17A) to be responsible for the development and progression of these malignancies. Therefore, we speculated that the variants in this gene might be associated with these cancer developments in Bangladeshi population. For evaluating the hypothesis, we investigated the association of IL-17A rs3748067 polymorphism with the susceptibility of both breast and cervical cancer. METHODS: This case-control study was performed on 156 breast cancer patients, 156 cervical cancer patients, and 156 controls using the tetra-primer amplification refractory mutation system-polymerase chain reaction. The statistical software package SPSS (version 25.0) was applied for analyses. The genetic association was measured by the odds ratio (OR) and 95% confidence intervals (CIs). A statistically significant association was considered when p-value ≤ 0.05. Functional analysis was performed using GEPIA and UALCAN databases. RESULTS: From the calculation of the association of IL-17A rs3748067 with breast cancer, it is found that no genotype or allele showed a statistically significant association (p>0.05). On the other hand, the analysis of IL-17A rs3748067 with cervical cancer demonstrated that CT genotype showed a significant association (CT vs. CC: OR=1.79, p=0.021). In the overdominant model, CT genotype also revealed a statistically significant association with cervical cancer, which is found to be statistically significant (OR=1.84, p=0.015). CONCLUSION: Our study summarizes that rs3748067 polymorphism in the IL-17A gene may be associated with cervical cancer but not breast cancer in Bangladeshi patients. However, we suggest studies in the future with a larger sample size.


Assuntos
Neoplasias da Mama , Predisposição Genética para Doença , Interleucina-17 , Polimorfismo de Nucleotídeo Único , Neoplasias do Colo do Útero , Humanos , Feminino , Interleucina-17/genética , Neoplasias da Mama/genética , Neoplasias do Colo do Útero/genética , Estudos de Casos e Controles , Bangladesh/epidemiologia , Pessoa de Meia-Idade , Adulto , Genótipo , Estudos de Associação Genética , Alelos , Razão de Chances , Idoso
12.
PLoS Comput Biol ; 19(12): e1011741, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38127835

RESUMO

The severity of the COVID-19 pandemic has created an emerging need to investigate the long-term effects of infection on patients. Many individuals are at risk of suffering pulmonary fibrosis due to the pathogenesis of lung injury and impairment in the healing mechanism. Fibroblasts are the central mediators of extracellular matrix (ECM) deposition during tissue regeneration, regulated by anti-inflammatory cytokines including transforming growth factor beta (TGF-ß). The TGF-ß-dependent accumulation of fibroblasts at the damaged site and excess fibrillar collagen deposition lead to fibrosis. We developed an open-source, multiscale tissue simulator to investigate the role of TGF-ß sources in the progression of lung fibrosis after SARS-CoV-2 exposure, intracellular viral replication, infection of epithelial cells, and host immune response. Using the model, we predicted the dynamics of fibroblasts, TGF-ß, and collagen deposition for 15 days post-infection in virtual lung tissue. Our results showed variation in collagen area fractions between 2% and 40% depending on the spatial behavior of the sources (stationary or mobile), the rate of activation of TGF-ß, and the duration of TGF-ß sources. We identified M2 macrophages as primary contributors to higher collagen area fraction. Our simulation results also predicted fibrotic outcomes even with lower collagen area fraction when spatially-localized latent TGF-ß sources were active for longer times. We validated our model by comparing simulated dynamics for TGF-ß, collagen area fraction, and macrophage cell population with independent experimental data from mouse models. Our results showed that partial removal of TGF-ß sources changed the fibrotic patterns; in the presence of persistent TGF-ß sources, partial removal of TGF-ß from the ECM significantly increased collagen area fraction due to maintenance of chemotactic gradients driving fibroblast movement. The computational findings are consistent with independent experimental and clinical observations of collagen area fractions and cell population dynamics not used in developing the model. These critical insights into the activity of TGF-ß sources may find applications in the current clinical trials targeting TGF-ß for the resolution of lung fibrosis.


Assuntos
COVID-19 , Fibrose Pulmonar , Animais , Camundongos , Humanos , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/patologia , Pandemias , COVID-19/metabolismo , SARS-CoV-2/metabolismo , Pulmão/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Fibrose , Colágeno/metabolismo , Fibroblastos/metabolismo
13.
Bioorg Med Chem Lett ; 108: 129801, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38777279

RESUMO

Novel saturated 6-(4'-aryloxy phenyl) vinyl 1,2,4-trioxanes 12a(1-3)-12d(1-3) and 13a(1-3)-13d(1-3) have been designed and synthesized, in one single step from diimide reduction of 11a(1-3)-11d(1-3). All the newly synthesized trioxanes were evaluated for their antimalarial activity against multi-drug resistant Plasmodium yoelii nigeriensis via oral route. Cyclopentane-based trioxanes 12b1, 12c1 and 12d1, provided 100 % protection to the infected mice at 24 mg/kg × 4 days. The most active compound of the series, trioxane 12b1, provided 100 % protection even at 12 mg/kg × 4 days and 60 % protection at 6 mg/kg × 4 days. The currently used drug, ß-arteether provides only 20 % protection at 24 mg/kg × 4 days.


Assuntos
Antimaláricos , Resistência a Múltiplos Medicamentos , Compostos Heterocíclicos , Malária , Plasmodium yoelii , Animais , Plasmodium yoelii/efeitos dos fármacos , Antimaláricos/farmacologia , Antimaláricos/química , Antimaláricos/síntese química , Camundongos , Administração Oral , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Malária/tratamento farmacológico , Relação Estrutura-Atividade , Compostos Heterocíclicos/química , Compostos Heterocíclicos/farmacologia , Compostos Heterocíclicos/síntese química , Estrutura Molecular , Modelos Animais de Doenças , Testes de Sensibilidade Parasitária
14.
Org Biomol Chem ; 22(23): 4704-4719, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38775495

RESUMO

A trio of Ir(III) complexes that are held together by a picolinamidato moiety were created. In our earlier research, we demonstrated the catalytic activity of the complexes for producing alpha-alkylated ketones from a ketone or secondary alcohol with a primary alcohol in the presence of a catalytic amount of a Cp*Ir(III) catalyst and tBuOK in toluene at 110 °C using the hydrogen-borrowing technique. Earlier many research groups had synthesized quinoline, pyrrole, and pyridine derivatives using 2-amino alcohol and ketone or secondary alcohol derivatives as starting materials, but in all those cases the reaction conditions are not suitable in terms of green synthesis like more catalyst loading, base loading, long reaction time, and high temperature. In addition, most of the reactions contain phosphine a hazardous by-product, along with the catalyst. Keeping in mind these shortcomings, we tried to expand the use of our catalysts after achieving an excellent result in our previous work, and we were successful in producing quinoline, pyrrole, and pyridine derivatives through acceptor-less dehydrogenative coupling (ADC) procedures at 90-110 °C under neat/solvent-free conditions and achieved good to exceptional yields of those nitrogen-containing heterocycles. This methodology is attractive because it is environmentally benign and allows for the "green" synthesis of nitrogen-containing heterocycles. All that is required is a modest quantity of catalyst and base, and the by-products are merely H2O and H2.

15.
Nanotechnology ; 35(36)2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38848694

RESUMO

Thermal rectifiers are essential in optimizing heat dissipation in solid-state devices to enhance energy efficiency, reliability, and overall performance. In this study, we experimentally investigate the thermal rectification phenomenon in suspended asymmetric graphene ribbons (GRs). The asymmetry within the graphene is introduced by incorporating periodic parallel nanoribbons on one side of the GR while maintaining the other side in a pristine form. Our findings reveal a substantial thermal rectification effect in these asymmetric graphene devices, reaching up to 45% at room temperature and increasing further at lower environmental temperatures. This effect is attributed to a significant thermal conductivity contrast between pristine graphene and nanoribbon graphene within the asymmetric structure. We observe that the incorporation of nanoribbons leads to a notable reduction in thermal conductivity, primarily due to phonon scattering and bottleneck effects near the nanoribbon edges. These findings suggest that graphene structures exhibiting asymmetry, facilitated by parallel nanoribbons, hold promise for effective heat management at the nanoscale level and the development of practical phononic devices.

16.
Epidemiol Infect ; 152: e14, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38178722

RESUMO

Using two rounds of serosurveillance, we aimed to observe the COVID-19 vaccination status and the dynamics of antibody responses to different vaccines among urban slum and non-slum populations of Bangladesh. Adults (>18 years) and children (10-17 years) were enrolled in March and October 2022. Data including COVID-19 vaccine types and dosage uptake were collected. SARS-CoV-2 spike (S)-specific antibodies were measured in blood. The proportion of vaccinated children was significantly lower among slum than non-slum populations. Two doses of vaccines showed an increase in the level of anti-S-antibodies up to 2 months, followed by reduced levels at 2-6 months and a resurgence at 6-12 months. Children showed significantly higher anti-S-antibodies after two doses of the Pfizer-BioNTech vaccine than adults; however, after 6 months, the level of antibodies declined in younger children (10 - < 12 years). In a mixed vaccine approach, mRNA vaccines contributed to the highest antibody response whether given as the first two doses or as the third dose. Our findings emphasized the need for increasing the coverage of COVID-19 vaccination among slum children and booster dosing among all children. The use of mRNA vaccines in the mixed vaccination approach was found to be useful in boosting the antibody response to SARS-CoV-2.


Assuntos
COVID-19 , Áreas de Pobreza , Adulto , Criança , Humanos , Vacinas contra COVID-19 , População Urbana , Bangladesh/epidemiologia , Vacinas de mRNA , COVID-19/epidemiologia , COVID-19/prevenção & controle , SARS-CoV-2
17.
Bioorg Chem ; 150: 107563, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38885547

RESUMO

In this study, seven isoniazid-hydrazone derivatives (3a-g) were synthesized and their structures elucidated by chromatographic techniques, and then the antiproliferative effects of these compounds on various cancer cells were tested. The advanced anticancer mechanism of the most potent compound was then investigated. Antiproliferative activities of the synthesized compounds were evaluated on human breast cancer MCF-7, lung cancer A-549, colon cancer HT-29, and non-cancerous mouse fibroblast 3T3-L1 cell lines by XTT assay. Flow cytometry analysis were carried out to determine cell cycle distribution, apoptosis, mitochondrial membrane potential, multi-caspase activity, and expression of PI3K/AKT signaling pathway. The XTT results showed that all the title molecules displayed cytotoxic activity at varying strengths in different dose ranges, and among them, the strongest cytotoxic effect and high selectivity were exerted by 3d against MCF-7 cells with the IC50 value of 11.35 µM and selectivity index of 8.65. Flow cytometry results revealed that compound 3d induced apoptosis through mitochondrial membrane disruption and multi-caspase activation in MCF-7 cells. It also inhibited the cell proliferation via inhibition of expression of PI3K/AKT and arrested the cell cycle at G0/G1 phase. In conclusion, all these data disclosed that among the synthesized compounds, 3d is notable for in vivo anticancer studies.

18.
Artigo em Inglês | MEDLINE | ID: mdl-38967713

RESUMO

PURPOSE OF REVIEW: The elderly population typically suffer from a variety of diseases that mostly reflect the degenerative changes linked with the aging process. These diseases may be exacerbated by acute pain or by an abrupt aggravation of previously stable chronic pain. RECENT FINDINGS: Physical and psychological changes associated with aging may influence one's experience of pain and, as a result, the severity of pain. Pain treatment in the elderly can be complex and is often a budgetary burden on the nation's health care system. These difficulties arise, in part, because of unanticipated pharmacodynamics, changed pharmacokinetics, and polypharmacy interactions. Therefore, it is critical to integrate a multidisciplinary team to develop a management strategy that incorporates medical, psychological, and surgical methods to control persistent pain conditions. It is in this critical process that pain prediction models can be of great use. The purpose of pain prediction models for the elderly is the use of mathematical models to predict the occurrence and intensity of pain and pain-related conditions. These mathematical models employ a vast quantity of data to ascertain the many risk factors for the development of pain problems in the elderly, whether said risks are adjustable or not. These models will pave the way for more informed medical decision making that are based on the findings of thousands of patients who have previously experienced the same illness and related pain conditions. However, future additional research needs to be undertaken to build prediction models that are not constrained by substantial legal or methodological limitations.

19.
Curr Pain Headache Rep ; 28(4): 211-227, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38214834

RESUMO

PURPOSE OF REVIEW: The combination of ketamine with propofol and dexmedetomidine has gained popularity for sedation and general anesthesia in different populations. In our meta-nalysis, we helped the anesthesiologists to know the efficiency and the efficacy of both combinations in adult and pediatric patients. METHODS: We searched PubMed, CENTRAL, Web of Science, and Scopus from inception to August 1, 2023. Our outcome parameters for efficacy were recovery time, pain score, and physician satisfaction while for safety were the related cardiorespiratory, neurological, and gastrointestinal adverse events. RECENT FINDINGS: Twenty-two trials were included with a total of 1429 patients. We found a significantly longer recovery time in the ketadex group of 7.59 min (95% CI, 4.92, 10.26; I2 = 94%) and a significantly less pain score of - 0.72 (95% CI, - 1.10, - 0.34; I2 = 0%). Adults had a significantly better physician satisfaction score with the ketofol group, odds ratio of 0.29 (95% CI, 0.12, 0.71; I2 = 0%). Recovery agitations were higher in the ketofol group with an odds ratio of 0.48 (95% CI, 0.24, 0.98; I2 = 36%). Furthermore, we found a significant difference between the combinations with a higher incidence in the ketadex group with pooled odds ratio of 1.75 (95% CI, 1.06, 2.88; I2 = 15%). Ketadex was associated with lower pain scores, hypoxic events and airway obstruction, and emergence agitation. At the same time, ketofol had much more clinician satisfaction which might be attributed to the shorter recovery time and lower incidence of nausea and vomiting. Therefore, we suppose that ketadex is the better combination in periprocedural sedation for both adult and pediatric patients who are not at greater risk for postoperative nausea and vomiting.


Assuntos
Dexmedetomidina , Ketamina , Propofol , Adulto , Humanos , Criança , Propofol/efeitos adversos , Ketamina/efeitos adversos , Anestesia Geral , Vômito , Dor , Hipnóticos e Sedativos/efeitos adversos
20.
BMC Pediatr ; 24(1): 336, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750481

RESUMO

BACKGROUND: Pakistan reports a significant burden of neonatal mortality, with infections as one of the major causes. We aim to assess the long-term impact of early infancy infections on neurodevelopmental outcomes during later childhood. METHODS: We conducted a prospective follow-up study of the cohort enrolled at the Karachi site of the Aetiology of Neonatal Infection in South Asia (ANISA) during 2019-2020. Children with a possible serious bacterial infection (based on the WHO IMCI algorithm) at early infancy were assessed for neurodevelopment at 6-9 years of age and compared with healthy controls. The Ten Questions (TQS) questionnaire, Strengths and Difficulties Questionnaire (SDQ), and Parent's Evaluation of Developmental Stage Assessment Level (PEDS: DM-AL) neurodevelopmental assessment tools, were administered and scored by the research staff who were blinded to the child's exposure status. Generalized Structural Equation Modelling (GSEM) was employed to verify relationships and associations among developmental milestones, anthropometry, and sociodemographic variables. RESULTS: A total of 398 children (241 cases and 157 controls) completed neurodevelopmental and growth assessments. Cases had a significantly higher rate of abnormal TQS scores (54.5% vs. 35.0%, p-value 0.001), greater delays in motor milestones (21.2% vs. 12.1%, p-value 0.02), lower fine motor skills (78.4 ± 1.4 vs. 83.2 ± 1.5, p-value 0.02). The receptive language skills were well-developed in both groups. According to the logistic regression model, exposure to infection during the first 59 days of life was associated with delayed TQS milestones (ß = -0.6, 95% CI -1.2,-0.04), TQS hearing domain (ß = -0.3, 95% CI: -1.2 to 0.7), PEDS: DM-AL fine motor domain (ß = -1.3, 95% CI: -4.4 to 1.7), PEDS: DM-AL receptive language development (ß = -1.1, 95% CI: -3.7 to 1.4) and child anthropometric measurements such as weight and height (ß = -0.2, 95% CI: -0.4 to 0.01 and ß = -0.2, 95% CI: -0.4 to -0.01, respectively). Early pSBI exposure was positively associated with PEDS: DM-AL self-help domain (ß = 0.6, 95% CI: -1.2 to 2.4) and SDQ-P overall score (ß = 0.02, 95% CI: -0.3 to 0.3). CONCLUSION: Children exposed to PSBI during early infancy have higher rates of abnormal development, motor delays, and lower fine motor skills during later childhood in Pakistan. Socioeconomic challenges and limited healthcare access contribute to these challenges, highlighting the need for long-term follow-ups with integrated neurodevelopment assessments.


Assuntos
Transtornos do Neurodesenvolvimento , Humanos , Paquistão/epidemiologia , Masculino , Estudos Prospectivos , Feminino , Criança , Lactente , Seguimentos , Recém-Nascido , Transtornos do Neurodesenvolvimento/etiologia , Transtornos do Neurodesenvolvimento/epidemiologia , Infecções Bacterianas/epidemiologia , Desenvolvimento Infantil , Estudos de Casos e Controles
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