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1.
Cell ; 185(22): 4190-4205.e25, 2022 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-36243004

RESUMEN

Neuroepithelial crosstalk is critical for gut physiology. However, the mechanisms by which sensory neurons communicate with epithelial cells to mediate gut barrier protection at homeostasis and during inflammation are not well understood. Here, we find that Nav1.8+CGRP+ nociceptor neurons are juxtaposed with and signal to intestinal goblet cells to drive mucus secretion and gut protection. Nociceptor ablation led to decreased mucus thickness and dysbiosis, while chemogenetic nociceptor activation or capsaicin treatment induced mucus growth. Mouse and human goblet cells expressed Ramp1, receptor for the neuropeptide CGRP. Nociceptors signal via the CGRP-Ramp1 pathway to induce rapid goblet cell emptying and mucus secretion. Notably, commensal microbes activated nociceptors to control homeostatic CGRP release. In the absence of nociceptors or epithelial Ramp1, mice showed increased epithelial stress and susceptibility to colitis. Conversely, CGRP administration protected nociceptor-ablated mice against colitis. Our findings demonstrate a neuron-goblet cell axis that orchestrates gut mucosal barrier protection.


Asunto(s)
Colitis , Células Caliciformes , Ratones , Humanos , Animales , Células Caliciformes/metabolismo , Nociceptores/metabolismo , Péptido Relacionado con Gen de Calcitonina/metabolismo , Colitis/metabolismo , Moco/metabolismo , Proteína 1 Modificadora de la Actividad de Receptores/metabolismo
2.
Cell ; 162(1): 45-58, 2015 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-26095253

RESUMEN

Colorectal cancer is a leading cause of cancer-related deaths. Mutations in the innate immune sensor AIM2 are frequently identified in patients with colorectal cancer, but how AIM2 modulates colonic tumorigenesis is unknown. Here, we found that Aim2-deficient mice were hypersusceptible to colonic tumor development. Production of inflammasome-associated cytokines and other inflammatory mediators was largely intact in Aim2-deficient mice; however, intestinal stem cells were prone to uncontrolled proliferation. Aberrant Wnt signaling expanded a population of tumor-initiating stem cells in the absence of AIM2. Susceptibility of Aim2-deficient mice to colorectal tumorigenesis was enhanced by a dysbiotic gut microbiota, which was reduced by reciprocal exchange of gut microbiota with healthy wild-type mice. These findings uncover a synergy between a specific host genetic factor and gut microbiota in determining the susceptibility to colorectal cancer. Therapeutic modulation of AIM2 expression and microbiota has the potential to prevent colorectal cancer.


Asunto(s)
Proliferación Celular , Neoplasias Colorrectales/metabolismo , Proteínas de Unión al ADN/metabolismo , Células Madre/patología , Animales , Azoximetano , Colitis/inducido químicamente , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/inmunología , Neoplasias Colorrectales/patología , Sulfato de Dextran , Enterocitos/patología , Tracto Gastrointestinal/microbiología , Inflamasomas/metabolismo , Ratones , Mutación , Células Madre/metabolismo
3.
Nature ; 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38768635

RESUMEN

Rare coding variants that significantly impact function provide insights into the biology of a gene1-3. However, ascertaining their frequency requires large sample sizes4-8. Here, we present a catalogue of human protein-coding variation, derived from exome sequencing of 983,578 individuals across diverse populations. 23% of the Regeneron Genetics Center Million Exome data (RGC-ME) comes from non-European individuals of African, East Asian, Indigenous American, Middle Eastern, and South Asian ancestry. This catalogue includes over 10.4 million missense and 1.1 million predicted loss-of-function (pLOF) variants. We identify individuals with rare biallelic pLOF variants in 4,848 genes, 1,751 of which have not been previously reported. From precise quantitative estimates of selection against heterozygous loss-of-function, we identify 3,988 loss-of-function intolerant genes, including 86 that were previously assessed as tolerant and 1,153 lacking established disease annotation. We also define regions of missense depletion at high resolution. Notably, 1,482 genes have regions depleted of missense variants despite being tolerant to pLOF variants. Finally, we estimate that 3% of individuals have a clinically actionable genetic variant, and that 11,773 variants reported in ClinVar with unknown significance are likely to be deleterious cryptic splice sites. To facilitate variant interpretation and genetics-informed precision medicine, we make this important resource of coding variation from the RGC-ME accessible via a public variant allele frequency browser.

4.
Nature ; 623(7989): 1044-1052, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37993709

RESUMEN

All nucleated cells express major histocompatibility complex I and interferon-γ (IFNγ) receptor1, but an epithelial cell-specific function of IFNγ signalling or antigen presentation by means of major histocompatibility complex I has not been explored. We show here that on sensing IFNγ, colonic epithelial cells productively present pathogen and self-derived antigens to cognate intra-epithelial T cells, which are critically located at the epithelial barrier. Antigen presentation by the epithelial cells confers extracellular ATPase expression in cognate intra-epithelial T cells, which limits the accumulation of extracellular adenosine triphosphate and consequent activation of the NLRP3 inflammasome in tissue macrophages. By contrast, antigen presentation by the tissue macrophages alongside inflammasome-associated interleukin-1α and interleukin-1ß production promotes a pathogenic transformation of CD4+ T cells into granulocyte-macrophage colony-stimulating-factor (GM-CSF)-producing T cells in vivo, which promotes colitis and colorectal cancer. Taken together, our study unravels critical checkpoints requiring IFNγ sensing and antigen presentation by epithelial cells that control the development of pathogenic CD4+ T cell responses in vivo.


Asunto(s)
Presentación de Antígeno , Colon , Células Epiteliales , Interferón gamma , Adenosina Trifosfatasas/metabolismo , Adenosina Trifosfato/metabolismo , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/patología , Colitis/inmunología , Colitis/patología , Colitis/prevención & control , Colon/citología , Colon/inmunología , Colon/patología , Neoplasias Colorrectales/inmunología , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/prevención & control , Células Epiteliales/inmunología , Células Epiteliales/metabolismo , Factor Estimulante de Colonias de Granulocitos y Macrófagos/inmunología , Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Inflamasomas/inmunología , Inflamasomas/metabolismo , Interferón gamma/inmunología , Interferón gamma/metabolismo , Interleucina-1alfa/inmunología , Interleucina-1beta/inmunología , Macrófagos/inmunología , Macrófagos/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo
5.
Immunity ; 49(3): 515-530.e5, 2018 09 18.
Artículo en Inglés | MEDLINE | ID: mdl-30231985

RESUMEN

Fungi represent a significant proportion of the gut microbiota. Aberrant immune responses to fungi are frequently observed in inflammatory bowel diseases (IBD) and colorectal cancer (CRC), and mutations in the fungal-sensing pathways are associated with the pathogenesis of IBD. Fungal recognition receptors trigger downstream signaling via the common adaptor protein CARD9 and the kinase SYK. Here we found that commensal gut fungi promoted inflammasome activation during AOM-DSS-induced colitis. Myeloid cell-specific deletion of Card9 or Syk reduced inflammasome activation and interleukin (IL)-18 maturation and increased susceptibility to colitis and CRC. IL-18 promoted epithelial barrier restitution and interferon-γ production by intestinal CD8+ T cells. Supplementation of IL-18 or transfer of wild-type myeloid cells reduced tumor burden in AOM-DSS-treated Card9-/- and Sykfl/flLysMCre/+ mice, whereas treatment with anti-fungal agents exacerbated colitis and CRC. CARD9 deletion changes the gut microbial landscape, suggesting that SYK-CARD9 signaling maintains a microbial ecology that promotes inflammasome activation and thereby restrains colitis and colon tumorigenesis.


Asunto(s)
Proteínas Adaptadoras de Señalización CARD/metabolismo , Colitis/inmunología , Neoplasias del Colon/inmunología , Hongos/inmunología , Microbioma Gastrointestinal/inmunología , Inflamasomas/metabolismo , Enfermedades Inflamatorias del Intestino/inmunología , Mucosa Intestinal/fisiología , Células Mieloides/fisiología , Quinasa Syk/metabolismo , Animales , Proteínas Adaptadoras de Señalización CARD/genética , Células Cultivadas , Colitis/inducido químicamente , Modelos Animales de Enfermedad , Humanos , Interleucina-18/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Transducción de Señal , Dodecil Sulfato de Sodio , Quinasa Syk/genética
6.
Am J Hum Genet ; 108(7): 1350-1355, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-34115965

RESUMEN

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19), a respiratory illness that can result in hospitalization or death. We used exome sequence data to investigate associations between rare genetic variants and seven COVID-19 outcomes in 586,157 individuals, including 20,952 with COVID-19. After accounting for multiple testing, we did not identify any clear associations with rare variants either exome wide or when specifically focusing on (1) 13 interferon pathway genes in which rare deleterious variants have been reported in individuals with severe COVID-19, (2) 281 genes located in susceptibility loci identified by the COVID-19 Host Genetics Initiative, or (3) 32 additional genes of immunologic relevance and/or therapeutic potential. Our analyses indicate there are no significant associations with rare protein-coding variants with detectable effect sizes at our current sample sizes. Analyses will be updated as additional data become available, and results are publicly available through the Regeneron Genetics Center COVID-19 Results Browser.


Asunto(s)
COVID-19/diagnóstico , COVID-19/genética , Secuenciación del Exoma , Exoma/genética , Predisposición Genética a la Enfermedad , Hospitalización/estadística & datos numéricos , COVID-19/inmunología , COVID-19/terapia , Femenino , Humanos , Interferones/genética , Masculino , Pronóstico , SARS-CoV-2 , Tamaño de la Muestra
7.
Bioorg Med Chem ; 97: 117515, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-38043245

RESUMEN

Over-expression of sigma-2 receptor in cancer cells provides an opportunity to develop molecular probes for diagnosis, even for non-receptor specific malignancies like triple negative breast cancers. In this work, a novel sigma-2 receptor ligand [THQ-DTPA] has been synthesized and characterized using 6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline (THQ) and diethylenetriaminepentaacetic acid (DTPA). The ligand is further chelated with 99mTc for application as metal based radiotracer [99mTc-THQ-DTPA]. Radiolabelling with 99mTc was achieved in an excellent yield of 98.0 ± 0.5% using stannous chloride as a reducing agent. The radioligand was found to be stable in human serum up-to 24 h, bio-compatible with less than 4% hemolysis, and exhibited high binding with sigma receptors isolated from rat liver membrane (Kd of 16.32 ± 4.93 nM and Bmax of 0.5232 ± 0.06 pmol/mg). Bio-distribution studies in triple-negative breast tumor bearing nude mice showed high tumor uptake after 30 min of injection with tumor/muscle (T/M) ratio of 3.58 ± 0.09. At 240 min, the T/M ratio (2.84 ± 0.20) decreased by 35% when administered in sigma blocked tumor bearing mice (1.81 ± 0.16) suggesting the selectivity of the ligand. Tumor imaging in gamma camera indicated a contrast of 3.56 at 30 min p.i. The above findings indicate that the ligand 99mTc-THQ-DTPA binds to sigma-2 receptors with high affinity and has potential for triple-negative breast tumor imaging.


Asunto(s)
Receptores sigma , Neoplasias de la Mama Triple Negativas , Ratas , Ratones , Humanos , Animales , Ligandos , Neoplasias de la Mama Triple Negativas/diagnóstico por imagen , Ratones Desnudos , Ácido Pentético , Receptores sigma/metabolismo , Radiofármacos , Línea Celular Tumoral , Tomografía Computarizada de Emisión de Fotón Único
8.
BMC Pregnancy Childbirth ; 24(1): 239, 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38575944

RESUMEN

BACKGROUND: Poor intrapartum care in India contributes to high maternal and newborn mortality. India's Labor Room Quality Improvement Initiative (LaQshya) launched in 2017, aims to improve intrapartum care by minimizing complications, enforcing protocols, and promoting respectful maternity care (RMC). However, limited studies pose a challenge to fully examine its potential to assess quality of maternal and newborn care. This study aims to bridge this knowledge gap and reviews LaQshya's ability to assess maternal and newborn care quality. Findings will guide modifications for enhancing LaQshya's effectiveness. METHODS: We reviewed LaQshya's ability to assess the quality of care through a two-step approach: a comprehensive descriptive analysis using document reviews to highlight program attributes, enablers, and challenges affecting LaQshya's quality assessment capability, and a comparison of its measurement parameters with the 352 quality measures outlined in the WHO Standards for Maternal and Newborn Care. Comparing LaQshya with WHO standards offers insights into how its measurement criteria align with global standards for assessing maternity and newborn care quality. RESULTS: LaQshya utilizes several proven catalysts to enhance and measure quality- institutional structures, empirical measures, external validation, certification, and performance incentives for high-quality care. The program also embodies contemporary methods like quality circles, rapid improvement cycles, ongoing facility training, and plan-do-check, and act (PDCA) strategies for sustained quality enhancement. Key drivers of LaQshya's assessment are- leadership, staff mentoring, digital infrastructure and stakeholder engagement from certified facilities. However, governance issues, understaffing, unclear directives, competency gaps, staff reluctance towards new quality improvement approaches inhibit the program, and its capacity to enhance quality of care. LaQshya addresses 76% of WHO's 352 quality measures for maternal and newborn care but lacks comprehensive assessment of crucial elements: harmful labor practices, mistreatment of mothers or newborns, childbirth support, and effective clinical leadership and supervision. CONCLUSION: LaQshya is a powerful model for evaluating quality of care, surpassing other global assessment tools. To achieve its maximum potential, we suggest strengthening district governance structures and offering tailored training programs for RMC and other new quality processes. Furthermore, expanding its quality measurement metrics to effectively assess provider accountability, patient outcomes, rights, staff supervision, and health facility leadership will increase its ability to assess quality improvements.


Asunto(s)
Servicios de Salud Materna , Mejoramiento de la Calidad , Femenino , Humanos , Recién Nacido , Embarazo , Madres , Parto , Calidad de la Atención de Salud
9.
PLoS Genet ; 17(12): e1009982, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34928956

RESUMEN

Sonic Hedgehog/GLI3 signaling is critical in regulating digit number, such that Gli3-deficiency results in polydactyly and Shh-deficiency leads to digit number reductions. SHH/GLI3 signaling regulates cell cycle factors controlling mesenchymal cell proliferation, while simultaneously regulating Grem1 to coordinate BMP-induced chondrogenesis. SHH/GLI3 signaling also coordinates the expression of additional genes, however their importance in digit formation remain unknown. Utilizing genetic and molecular approaches, we identified HES1 as a downstream modifier of the SHH/GLI signaling axis capable of inducing preaxial polydactyly (PPD), required for Gli3-deficient PPD, and capable of overcoming digit number constraints of Shh-deficiency. Our data indicate that HES1, a direct SHH/GLI signaling target, induces mesenchymal cell proliferation via suppression of Cdkn1b, while inhibiting chondrogenic genes and the anterior autopod boundary regulator, Pax9. These findings establish HES1 as a critical downstream effector of SHH/GLI3 signaling in the development of PPD.


Asunto(s)
Proteínas Hedgehog/genética , Proteínas del Tejido Nervioso/genética , Factor de Transcripción PAX9/genética , Polidactilia/genética , Pulgar/anomalías , Factor de Transcripción HES-1/genética , Proteína Gli3 con Dedos de Zinc/genética , Animales , División Celular/genética , Proliferación Celular/genética , Condrogénesis/genética , Cromatina/genética , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/genética , Modelos Animales de Enfermedad , Humanos , Esbozos de los Miembros/crecimiento & desarrollo , Esbozos de los Miembros/metabolismo , Mesodermo/crecimiento & desarrollo , Ratones , Polidactilia/patología , Pulgar/patología
10.
J Hand Ther ; 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38521687

RESUMEN

BACKGROUND: Hand grip strength is an established indicator of individual health status and is used as a biomarker for predicting mortality, disability, and disease risks. GripAble hand grip dynamometer offers a modernized approach to measuring grip strength with its digital and high-accuracy measurement system. PURPOSE: This study aimed to (1) assess the interrater reliability of maximum grip strength (MGS) measurement and (2) establish GripAble's own gender-, age group- and hand-stratified normative MGS reference values of the adult UK population. STUDY DESIGN: Cross-sectional study design. METHODS: Interrater reliability among three raters assessing 30 participants across diverse age groups was measured using the intraclass correlation. In the second study, 11 investigators gathered MGS data from 907 participants across diverse age groups and gender. The average, standard deviation, minimum, median, maximum, and percentiles of MGS were computed for each gender, age group, and hand (L/R). The relationship between MGS and age was examined using quantile regression analysis. Additionally, generalized linear model regression analysis was conducted to explore the influence of participants' demographics (gender, hand [L/R], hand length, hand circumference, age, weight, and height) on MGS. RESULTS: MGS measurements between raters showed excellent agreement (ICC(2,1) = 0.991, 95% confidence interval [0.98, 1.0]). The MGS and age relationship follows a curvilinear pattern, reaching a peak median MGS values of up to 20 kg between 30 and 49 years for females and up to 35 kg between 30 and 59 years for males. Subsequently, MGS declined as age advanced. Gender and hand (L/R) emerged as the primary factors influencing MGS, followed by hand length, hand circumference, age, weight, and height. CONCLUSIONS: The presented normative MGS reference values can be used for interpreting MGS measurements obtained from adults in the United Kingdom using GripAble. This study, along with previous studies on GripAble devices, confirms GripAble as a reliable and valid tool for measuring MGS.

11.
J Cell Sci ; 134(1)2021 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-33262314

RESUMEN

Osteoblasts are the principal bone-forming cells. As such, osteoblasts have enhanced demand for amino acids to sustain high rates of matrix synthesis associated with bone formation. The precise systems utilized by osteoblasts to meet these synthetic demands are not well understood. WNT signaling is known to rapidly stimulate glutamine uptake during osteoblast differentiation. Using a cell biology approach, we identified two amino acid transporters, γ(+)-LAT1 and ASCT2 (encoded by Slc7a7 and Slc1a5, respectively), as the primary transporters of glutamine in response to WNT. ASCT2 mediates the majority of glutamine uptake, whereas γ(+)-LAT1 mediates the rapid increase in glutamine uptake in response to WNT. Mechanistically, WNT signals through the canonical ß-catenin (CTNNB1)-dependent pathway to rapidly induce Slc7a7 expression. Conversely, Slc1a5 expression is regulated by the transcription factor ATF4 downstream of the mTORC1 pathway. Targeting either Slc1a5 or Slc7a7 using shRNA reduced WNT-induced glutamine uptake and prevented osteoblast differentiation. Collectively, these data highlight the critical nature of glutamine transport for WNT-induced osteoblast differentiation.This article has an associated First Person interview with the joint first authors of the paper.


Asunto(s)
Glutamina , Osteogénesis , Diferenciación Celular , Osteoblastos , Vía de Señalización Wnt , beta Catenina
12.
Chemistry ; 29(70): e202302106, 2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-37605950

RESUMEN

N-heterocyclic olefin (NHO) derivatives have an electron-rich as well as highly polarized carabon-carbon (C=C) double bond because of the electron-donating nature of nitrogen and sulphur atoms. While NHOs have been developing as novel organocatalysts and ligands for transition-metal complexes in various organic compound syntheses, different research groups are currently interested in preparing imidazole and triazolium-based chiral NHO catalysts. Some of them have been used for enantioselective organic transformations, but were still elusive. N-heterocyclic olefins, the alkylidene derivatives of N-heterocyclic carbenes (NHC), have shown promising results as effective promoters for numerous organic syntheses such as asymmetric catalysis, hydroborylation, hydrosilylation, reduction, CO2 sequestration, alkylation, cycloaddition, polymerization and the ring-opening reaction of aziridine and epoxides, esterification, C-F bond functionalization, amine coupling, trifluoromethyl thiolation, amination etc. NHOs catalysts with suitable structures can serve as a novel class of Lewis/Bronsted bases with strong basicity and high nucleophilicity properties.These facts strongly suggest their enormous chemical potential as sustainable catalysts for a wide variety of reactions in synthetic chemistry. The synthesis of NHOs and their properties are briefly reviewed in this article, along with a summary of the imidazole and triazole core of NHOs' most recent catalytic uses.

13.
Adv Appl Microbiol ; 123: 91-131, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37400175

RESUMEN

One of the biggest health related issues in the twenty-first century is cancer. The current therapeutic platforms have not advanced enough to keep up with the number of rising cases. The traditional therapeutic approaches frequently fail to produce the desired outcomes. Therefore, developing new and more potent remedies is crucial. Recently, investigating microorganisms as potential anti-cancer treatments have garnered a lot of attention. Tumor-targeting microorganisms are more versatile at inhibiting cancer than the majority of standard therapies. Bacteria preferentially gather and thrive inside tumors, where they can trigger anti-cancer immune responses. They can be further trained to generate and distribute anticancer drugs based on clinical requirements using straightforward genetic engineering approaches. To improve clinical outcomes, therapeutic strategies utilizing live tumor-targeting bacteria can be used either alone or in combination with existing anticancer treatments. On the other hand, oncolytic viruses that target cancer cells, gene therapy via viral vectors, and viral immunotherapy are other popular areas of biotechnological investigation. Therefore, viruses serve as a unique candidate for anti-tumor therapy. This chapter describes the role of microbes, primarily bacteria and viruses in anti-cancer therapeutics. The various approaches to utilizing microbes in cancer therapy are discussed and examples of microorganisms that are now in use or that are undergoing experimental research are briefly discussed. We further point out the hurdles and the prospects of microbes-based remedies for cancer treatment.


Asunto(s)
Antineoplásicos , Neoplasias , Viroterapia Oncolítica , Virus Oncolíticos , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Virus Oncolíticos/genética , Inmunoterapia , Antineoplásicos/uso terapéutico , Bacterias/genética
14.
Org Biomol Chem ; 21(6): 1316-1327, 2023 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-36648399

RESUMEN

Phenolic organochalcogen chain-breaking antioxidants, i.e. 6-bromo-8 (hexadecyltellanyl)-3,3-dimethyl-1,5-dihydro-[1,3]dioxepino[5,6-c]pyridin-9-ol and 2-methyl-2,3-dihydrobenzo[b]selenophene-5-ol, have been investigated in a two-phase (chlorobenzene/water) lipid peroxidation model system as potent inhibitors of lipid peroxyl radicals with various co-antioxidants at various pH values. The pH has a significant effect on the chain-breaking antioxidant activities of phenolic organochalcogens. The key chain-breaking mechanism profile was attributed to the first oxygen atom transfer from the lipid peroxyl radicals to the Se/Te atom, followed by hydrogen atom transfer in a solvent cage from the nearby phenolic group to the resulting alkoxyl radical. Finally, regeneration of organochalcogen antioxidants could take place in the presence of aqueous-soluble co-antioxidants. Also, in the presence of aqueous soluble N-acetylcysteine at pH 1-7, both antioxidants behaved as very good inhibitors of lipid peroxyl radicals. The role of aqueous soluble mild co-antioxidants in the regeneration studies of organochalcogen antioxidants has been investigated in a two-phase lipid peroxidation model system. The importance of the phase transfer catalyst has been explored in the inhibition studies of selenium containing antioxidants using an Fe(II) source. The overall pH-dependent antioxidant activities of organochalcogens depend on their hydrogen atom transfer ability, relative stability, and distribution in the aqueous/lipid phase.

15.
J Appl Microbiol ; 134(3)2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36914211

RESUMEN

AIM: This study was aimed to determine antimicrobial and antiviral activity of a novel lanthipeptide from a Brevibacillus sp. for disinfectant application. METHODS AND RESULTS: The antimicrobial peptide (AMP) was produced by a bacterial strain AF8 identified as a member of the genus Brevibacillus representing a novel species. Whole genome sequence analysis using BAGEL identified a putative complete biosynthetic gene cluster involved in lanthipeptide synthesis. The deduced amino acid sequence of lanthipeptide named as brevicillin, showed >30% similarity with epidermin. Mass determined by MALDI-MS and Q-TOF suggested posttranslational modifications like dehydration of all Ser and Thr amino acids to yield Dha and Dhb, respectively. Amino acid composition determined upon acid hydrolysis is in agreement with core peptide sequence deduced from the putative biosynthetic gene bvrAF8. Biochemical evidence along with stability features ascertained posttranslational modifications during formation of the core peptide. The peptide showed strong activity with 99% killing of pathogens at 12 µg ml-1 within 1 minute. Interestingly, it also showed potent anti-SARS-CoV-2 activity by inhibiting ∼99% virus growth at 10 µg ml-1 in cell culture-based assay. Brevicillin did not show dermal allergic reactions in BALB/c mice. CONCLUSION: This study provides detailed description of a novel lanthipeptide and demonstrates its effective antibacterial, antifungal and anti-SARS-CoV-2 activity.


Asunto(s)
Brevibacillus , COVID-19 , Animales , Ratones , Antifúngicos/farmacología , Antifúngicos/metabolismo , Brevibacillus/genética , Brevibacillus/metabolismo , Antivirales , Péptidos/química
16.
Public Health Nutr ; 26(1): 63-95, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35156607

RESUMEN

OBJECTIVE: To summarise available evidence on the nutritional status of school-age children and adolescents (5-19 years) from seven global regions and on interventions implemented to improve malnutrition in this population. SETTING: Global. DESIGN: Findings were compiled from seven scoping literature reviews, including data from low- and middle-income countries within the following UNICEF-defined global regions: East Asia and Pacific; Europe and Central Asia; South Asia; West and Central Africa; Eastern and Southern Africa; Middle East and North Africa and Latin America and the Caribbean. RESULTS: A double burden of malnutrition was evident across the world regions reviewed: stunting, thinness, anaemia and other micronutrient deficiencies persisted, alongside rising overweight and obesity prevalence. Transitions towards diets increasingly high in energy-dense, processed and micronutrient-poor foods were observed. Evidence from intervention studies was limited, but suggested that providing multiple micronutrient-fortified foods or beverages at school may effectively target micronutrient deficiencies and facilitate weight gain in undernourished populations. Interventions to prevent or manage overweight and obesity were even more limited. There was minimal evidence of using novel technological approaches to engage school-age children and adolescents, or of involving them in designing interventions. CONCLUSION: The limited data available on nutrition of school-age children and adolescents are neither standardised nor comparable. Consensus on methods for assessing nutritional status and its determinants for this age group is urgently needed to set targets and monitor progress. Additionally, strategies are required to ensure that nutritious, safe and sustainable diets are available, affordable and appealing.


Asunto(s)
Desnutrición , Estado Nutricional , Niño , Humanos , Adolescente , Preescolar , Adulto Joven , Adulto , Sobrepeso/epidemiología , Países en Desarrollo , Desnutrición/epidemiología , Desnutrición/prevención & control , Obesidad/epidemiología , Micronutrientes , Prevalencia
17.
J Hum Nutr Diet ; 36(6): 2295-2309, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37728211

RESUMEN

BACKGROUND: Global food systems are failing adolescents. Poor diet quality driving malnutrition among adolescents around the world and the quality of foods eaten by adolescents not only determines their health and development, but also is the foundation of thriving communities. The present study aimed to engage adolescents across low-income, middle-income and high-income countries to determine their lived experience of food, food systems and the challenges they face within their food systems. METHODS: The study used the Distributed Data Generation method pioneered by the Young and Resilient Research Centre, at Western Sydney University, to conduct workshops with adolescents aged 10-19 years across the globe in collaboration with UNICEF. Participatory workshops were designed to capture qualitative data on adolescents lived experiences and perspectives of their food systems, food sustainability and food security, and how improvements can be made. Thematic analysis was undertaken to analyse qualitative data. Descriptive statistics were generated for demographic data captured. RESULTS: Six hundred and forty adolescents across 18 countries participated. Three key themes emerged, which included experiences of food, challenges to food systems and strengthening food systems. Adolescents saw potential in empowering communities to create change and contribute to food system transformation. Adolescents called for inclusion in decision-making from local food practice to large global policy development. CONCLUSIONS: The study results demonstrated how adolescents experience their food systems and want to see sustainable change, although they also want to be a part of the change. Adolescents described that there needs to be an active choice to work with them, listen to their lived experience and across all levels of society strengthen food systems. To achieve this, adolescents need to be involved in decision-making around their food systems for a sustainable future.


Asunto(s)
Abastecimiento de Alimentos , Crecimiento Sostenible , Adolescente , Humanos , Niño , Adulto Joven
18.
AAPS PharmSciTech ; 24(8): 252, 2023 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-38049695

RESUMEN

Tuberculosis (TB) is among the top 10 infectious diseases worldwide. It is categorized among the leading killer diseases that are the reason for the death of millions of people globally. Although a standardized treatment regimen is available, non-adherence to treatment has increased multi-drug resistance (MDR) and extensive drug-resistant (XDR) TB development. Another challenge is targeting the death of TB reservoirs in the alveoli via conventional treatment. TB Drug resistance may emerge as a futuristic restraint of TB with the scarcity of effective Anti-tubercular drugs. The paradigm change towards nano-targeted drug delivery systems is mostly due to the absence of effective therapy and increased TB infection recurrent episodes with MDR. The emerging field of nanotechnology gave an admirable opportunity to combat MDR and XDR via accurate diagnosis with effective treatment. The new strategies targeting the lung via the pulmonary route may overcome the new incidence of MDR and enhance patient compliance. Therefore, this review highlights the importance and recent research on pulmonary drug delivery with nanotechnology along with prevalence, the need for the development of nanotechnology, beneficial aspects of nanomedicine, safety concerns of nanocarriers, and clinical studies.


Asunto(s)
Tuberculosis Extensivamente Resistente a Drogas , Mycobacterium tuberculosis , Tuberculosis Resistente a Múltiples Medicamentos , Humanos , Antituberculosos/uso terapéutico , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Tuberculosis Resistente a Múltiples Medicamentos/epidemiología , Tuberculosis Extensivamente Resistente a Drogas/tratamiento farmacológico , Tuberculosis Extensivamente Resistente a Drogas/epidemiología , Sistemas de Liberación de Medicamentos , Pulmón
19.
Matern Child Nutr ; : e13479, 2023 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-37014175

RESUMEN

The prevalence of overweight/obesity in adolescents has increased globally, including in low- and middle-income countries. Early adolescence provides an opportunity to develop and encourage positive health and behavioural practices, yet it is an understudied age group with limited information to guide and inform appropriate interventions. This study aims to determine the prevalence of overweight/obesity in young adolescents, aged between 10 and 14 years attending public schools in Addis Ababa, Ethiopia, and to explore the contributing factors. A cross-sectional school-based study was conducted. Adolescents completed individual questionnaires. Weight (kg) and height (m) measurements were converted to BMI-for-age and gender z-scores. Multivariate regression analysis was conducted to determine the associated factors. The overall prevalence of overweight/obesity was 8% among adolescents aged 10-14 years and it was significantly higher in females (13%) than males (2%). The diet quality for the majority of the adolescents was inadequate, putting them at risk for poor health outcomes. The contributors to overweight/obesity were different between males and females. Age and no access to a flush toilet were negatively associated with overweight/obesity in males and access to a computer, laptop or tablet was positively associated. In females, menarche was positively associated with overweight/obesity. Living with only their mother or another female adult and an increase in physical activity were negatively associated with overweight/obesity. There is a need to improve the diet quality of young adolescents in Ethiopia and understand the reasons why females are less physically active to limit the risk of poor diet-related health outcomes.

20.
Matern Child Nutr ; : e13492, 2023 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-37014188

RESUMEN

Mental health in adolescence is important for health and well-being throughout the life course, but evidence from Sub-Saharan Africa is sparse. This study aimed to assess the correlates of internalizing, externalizing and cumulative problems among early adolescents. This study used cross-sectional survey data from 3516 school-going adolescents in Ouagadougou, Burkina Faso; Addis Ababa, Ethiopia and Dar es Salaam, Tanzania. We used a 25-item Strengths and Difficulties Questionnaire to measure internalizing, externalizing and cumulative problems. We carried out multi-variable linear regression analyses with the estimation of adjusted mean differences and 95% confidence intervals, to determine the factors associated with internalizing, externalizing and cumulative problems. Overall, 1 in 8 adolescents had internalizing problems, while 1 in 10 had externalizing problems. In two sites, having friends was related to lower internalizing problems, while repeating a grade, physical fights and household food insecurity were related to greater internalizing problems. Household food insecurity and involvement in physical fights were associated with greater externalizing problems across sites, while repeating a grade was linked with greater externalizing problems in two sites. Having a caring adult in school was associated with fewer externalizing problems across sites, while having friends was associated with fewer externalizing problems in two sites. Overall, having friends was related to fewer cumulative problems, while physical fights and household food insecurity were related to higher cumulative problems. School-based mental health and food programs may be useful in addressing social-emotional problems among school-aged adolescents in Burkina Faso, Ethiopia and Tanzania.

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