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1.
N Engl J Med ; 390(1): 32-43, 2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38169488

RESUMEN

BACKGROUND: Exposure to household air pollution is a risk factor for severe pneumonia. The effect of replacing biomass cookstoves with liquefied petroleum gas (LPG) cookstoves on the incidence of severe infant pneumonia is uncertain. METHODS: We conducted a randomized, controlled trial involving pregnant women 18 to 34 years of age and between 9 to less than 20 weeks' gestation in India, Guatemala, Peru, and Rwanda from May 2018 through September 2021. The women were assigned to cook with unvented LPG stoves and fuel (intervention group) or to continue cooking with biomass fuel (control group). In each trial group, we monitored adherence to the use of the assigned cookstove and measured 24-hour personal exposure to fine particulate matter (particles with an aerodynamic diameter of ≤2.5 µm [PM2.5]) in the women and their offspring. The trial had four primary outcomes; the primary outcome for which data are presented in the current report was severe pneumonia in the first year of life, as identified through facility surveillance or on verbal autopsy. RESULTS: Among 3200 pregnant women who had undergone randomization, 3195 remained eligible and gave birth to 3061 infants (1536 in the intervention group and 1525 in the control group). High uptake of the intervention led to a reduction in personal exposure to PM2.5 among the children, with a median exposure of 24.2 µg per cubic meter (interquartile range, 17.8 to 36.4) in the intervention group and 66.0 µg per cubic meter (interquartile range, 35.2 to 132.0) in the control group. A total of 175 episodes of severe pneumonia were identified during the first year of life, with an incidence of 5.67 cases per 100 child-years (95% confidence interval [CI], 4.55 to 7.07) in the intervention group and 6.06 cases per 100 child-years (95% CI, 4.81 to 7.62) in the control group (incidence rate ratio, 0.96; 98.75% CI, 0.64 to 1.44; P = 0.81). No severe adverse events were reported to be associated with the intervention, as determined by the trial investigators. CONCLUSIONS: The incidence of severe pneumonia among infants did not differ significantly between those whose mothers were assigned to cook with LPG stoves and fuel and those whose mothers were assigned to continue cooking with biomass stoves. (Funded by the National Institutes of Health and the Bill and Melinda Gates Foundation; HAPIN ClinicalTrials.gov number, NCT02944682.).


Asunto(s)
Contaminación del Aire Interior , Biomasa , Culinaria , Exposición por Inhalación , Petróleo , Neumonía , Femenino , Humanos , Lactante , Embarazo , Contaminación del Aire Interior/efectos adversos , Contaminación del Aire Interior/análisis , Culinaria/métodos , Material Particulado/efectos adversos , Material Particulado/análisis , Petróleo/efectos adversos , Neumonía/etiología , Adolescente , Adulto Joven , Adulto , Internacionalidad , Exposición por Inhalación/efectos adversos , Exposición por Inhalación/análisis , Exposición Materna/efectos adversos , Efectos Tardíos de la Exposición Prenatal/etiología
2.
N Engl J Med ; 390(1): 44-54, 2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38169489

RESUMEN

BACKGROUND: Household air pollution is associated with stunted growth in infants. Whether the replacement of biomass fuel (e.g., wood, dung, or agricultural crop waste) with liquefied petroleum gas (LPG) for cooking can reduce the risk of stunting is unknown. METHODS: We conducted a randomized trial involving 3200 pregnant women 18 to 34 years of age in four low- and middle-income countries. Women at 9 to less than 20 weeks' gestation were randomly assigned to use a free LPG cookstove with continuous free fuel delivery for 18 months (intervention group) or to continue using a biomass cookstove (control group). The length of each infant was measured at 12 months of age, and personal exposures to fine particulate matter (particles with an aerodynamic diameter of ≤2.5 µm) were monitored starting at pregnancy and continuing until the infants were 1 year of age. The primary outcome for which data are presented in the current report - stunting (defined as a length-for-age z score that was more than two standard deviations below the median of a growth standard) at 12 months of age - was one of four primary outcomes of the trial. Intention-to-treat analyses were performed to estimate the relative risk of stunting. RESULTS: Adherence to the intervention was high, and the intervention resulted in lower prenatal and postnatal 24-hour personal exposures to fine particulate matter than the control (mean prenatal exposure, 35.0 µg per cubic meter vs. 103.3 µg per cubic meter; mean postnatal exposure, 37.9 µg per cubic meter vs. 109.2 µg per cubic meter). Among 3061 live births, 1171 (76.2%) of the 1536 infants born to women in the intervention group and 1186 (77.8%) of the 1525 infants born to women in the control group had a valid length measurement at 12 months of age. Stunting occurred in 321 of the 1171 infants included in the analysis (27.4%) of the infants born to women in the intervention group and in 299 of the 1186 infants included in the analysis (25.2%) of those born to women in the control group (relative risk, 1.10; 98.75% confidence interval, 0.94 to 1.29; P = 0.12). CONCLUSIONS: An intervention strategy starting in pregnancy and aimed at mitigating household air pollution by replacing biomass fuel with LPG for cooking did not reduce the risk of stunting in infants. (Funded by the National Institutes of Health and the Bill and Melinda Gates Foundation; HAPIN ClinicalTrials.gov number, NCT02944682.).


Asunto(s)
Contaminación del Aire Interior , Petróleo , Lactante , Femenino , Humanos , Embarazo , Contaminación del Aire Interior/efectos adversos , Contaminación del Aire Interior/análisis , Biomasa , Material Particulado/efectos adversos , Material Particulado/análisis , Culinaria , Trastornos del Crecimiento/epidemiología , Trastornos del Crecimiento/etiología , Trastornos del Crecimiento/prevención & control
3.
Nature ; 587(7835): 605-609, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33177710

RESUMEN

Expansion of anthropogenic noise and night lighting across our planet1,2 is of increasing conservation concern3-6. Despite growing knowledge of physiological and behavioural responses to these stimuli from single-species and local-scale studies, whether these pollutants affect fitness is less clear, as is how and why species vary in their sensitivity to these anthropic stressors. Here we leverage a large citizen science dataset paired with high-resolution noise and light data from across the contiguous United States to assess how these stimuli affect reproductive success in 142 bird species. We find responses to both sensory pollutants linked to the functional traits and habitat affiliations of species. For example, overall nest success was negatively correlated with noise among birds in closed environments. Species-specific changes in reproductive timing and hatching success in response to noise exposure were explained by vocalization frequency, nesting location and diet. Additionally, increased light-gathering ability of species' eyes was associated with stronger advancements in reproductive timing in response to light exposure, potentially creating phenological mismatches7. Unexpectedly, better light-gathering ability was linked to reduced clutch failure and increased overall nest success in response to light exposure, raising important questions about how responses to sensory pollutants counteract or exacerbate responses to other aspects of global change, such as climate warming. These findings demonstrate that anthropogenic noise and light can substantially affect breeding bird phenology and fitness, and underscore the need to consider sensory pollutants alongside traditional dimensions of the environment that typically inform biodiversity conservation.


Asunto(s)
Aves/fisiología , Iluminación/efectos adversos , Ruido/efectos adversos , Reproducción/efectos de la radiación , Animales , Aves/clasificación , Ciencia Ciudadana , Tamaño de la Nidada/efectos de la radiación , Espacios Confinados , Conjuntos de Datos como Asunto , Dieta/veterinaria , Ecosistema , Femenino , Mapeo Geográfico , Masculino , Comportamiento de Nidificación/fisiología , Comportamiento de Nidificación/efectos de la radiación , Fenómenos Fisiológicos Oculares/efectos de la radiación , Reproducción/fisiología , Especificidad de la Especie , Estados Unidos , Vocalización Animal/efectos de la radiación
4.
N Engl J Med ; 387(19): 1735-1746, 2022 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-36214599

RESUMEN

BACKGROUND: Exposure during pregnancy to household air pollution caused by the burning of solid biomass fuel is associated with adverse health outcomes, including low birth weight. Whether the replacement of a biomass cookstove with a liquefied petroleum gas (LPG) cookstove would result in an increase in birth weight is unclear. METHODS: We performed a randomized, controlled trial involving pregnant women (18 to <35 years of age and at 9 to <20 weeks' gestation as confirmed on ultrasonography) in Guatemala, India, Peru, and Rwanda. The women were assigned in a 1:1 ratio to use a free LPG cookstove and fuel (intervention group) or to continue using a biomass cookstove (control group). Birth weight, one of four prespecified primary outcomes, was the primary outcome for this report; data for the other three outcomes are not yet available. Birth weight was measured within 24 hours after birth. In addition, 24-hour personal exposures to fine particulate matter (particles with a diameter of ≤2.5 µm [PM2.5]), black carbon, and carbon monoxide were measured at baseline and twice during pregnancy. RESULTS: A total of 3200 women underwent randomization; 1593 were assigned to the intervention group, and 1607 to the control group. Uptake of the intervention was nearly complete, with traditional biomass cookstoves being used at a median rate of less than 1 day per month. After randomization, the median 24-hour personal exposure to fine particulate matter was 23.9 µg per cubic meter in the intervention group and 70.7 µg per cubic meter in the control group. Among 3061 live births, a valid birth weight was available for 94.9% of the infants born to women in the intervention group and for 92.7% of infants born to those in the control group. The mean (±SD) birth weight was 2921±474.3 g in the intervention group and 2898±467.9 g in the control group, for an adjusted mean difference of 19.6 g (95% confidence interval, -10.1 to 49.2). CONCLUSIONS: The birth weight of infants did not differ significantly between those born to women who used LPG cookstoves and those born to women who used biomass cookstoves. (Funded by the National Institutes of Health and the Bill and Melinda Gates Foundation; HAPIN ClinicalTrials.gov number, NCT02944682.).


Asunto(s)
Contaminación del Aire Interior , Peso al Nacer , Culinaria , Material Particulado , Petróleo , Femenino , Humanos , Embarazo , Contaminación del Aire Interior/efectos adversos , Contaminación del Aire Interior/análisis , Biomasa , Culinaria/métodos , Material Particulado/efectos adversos , Material Particulado/análisis , Petróleo/efectos adversos , Petróleo/análisis , Recién Nacido , Adolescente , Adulto Joven , Adulto
5.
Circ Res ; 133(12): 1040-1055, 2023 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-37961889

RESUMEN

BACKGROUND: Nitric oxide (NO) has been identified as a signaling molecule generated during ß-adrenergic receptor stimulation in the heart. Furthermore, a role for NO in triggering spontaneous Ca2+ release via S-nitrosylation of CaMKIIδ (Ca2+/calmodulin kinase II delta) is emerging. NO donors are routinely used clinically for their cardioprotective effects on the heart, but it is unknown how NO donors modulate the proarrhythmic CaMKII to alter cardiac arrhythmia incidence. We test the role of S-nitrosylation of CaMKIIδ at the Cysteine-273 inhibitory site and cysteine-290 activating site in cardiac Ca2+ handling and arrhythmogenesis before and during ß-adrenergic receptor stimulation. METHODS: We measured Ca2+-handling in isolated cardiomyocytes from C57BL/6J wild-type (WT) mice and mice lacking CaMKIIδ expression (CaMKIIδ-KO) or with deletion of the S-nitrosylation site on CaMKIIδ at cysteine-273 or cysteine-290 (CaMKIIδ-C273S and -C290A knock-in mice). Cardiomyocytes were exposed to NO donors, S-nitrosoglutathione (GSNO; 150 µM), sodium nitroprusside (200 µM), and ß-adrenergic agonist isoproterenol (100 nmol/L). RESULTS: Both WT and CaMKIIδ-KO cardiomyocytes responded to isoproterenol with a full inotropic and lusitropic Ca2+ transient response as well as increased Ca2+ spark frequency. However, the increase in Ca2+ spark frequency was significantly attenuated in CaMKIIδ-KO cardiomyocytes. The protection from isoproterenol-induced Ca2+ sparks and waves was mimicked by GSNO pretreatment in WT cardiomyocytes but lost in CaMKIIδ-C273S cardiomyocytes. When GSNO was applied after isoproterenol, this protection was not observed in WT or CaMKIIδ-C273S but was apparent in CaMKIIδ-C290A. In Langendorff-perfused isolated hearts, GSNO pretreatment limited isoproterenol-induced arrhythmias in WT but not CaMKIIδ-C273S hearts, while GSNO exposure after isoproterenol sustained or exacerbated arrhythmic events. CONCLUSIONS: We conclude that prior S-nitrosylation of CaMKIIδ at cysteine-273 can limit subsequent ß-adrenergic receptor-induced arrhythmias, but that S-nitrosylation at cysteine-290 might worsen or sustain ß-adrenergic receptor-induced arrhythmias. This has important implications for the administration of NO donors in the clinical setting.


Asunto(s)
Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina , Óxido Nítrico , Ratones , Animales , Isoproterenol/farmacología , Óxido Nítrico/metabolismo , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Cisteína/metabolismo , Ratones Endogámicos C57BL , Arritmias Cardíacas/inducido químicamente , Arritmias Cardíacas/metabolismo , Miocitos Cardíacos/metabolismo , Fosforilación , Receptores Adrenérgicos beta/metabolismo , Calcio/metabolismo , Retículo Sarcoplasmático/metabolismo
6.
Nano Lett ; 24(21): 6433-6440, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38747334

RESUMEN

Soap bubbles exhibit abundant fascinating phenomena throughout the entire life of evolution with different fundamental physics governing them. Nevertheless, the complicated dynamics of small objects in soap films are still unrevealed. Here, we report the first observation of spontaneous particle ordering in a complicated galaxy of soap films without any external energy. The balance of interfacial tension at two liquid-gas interfaces is theoretically predicted to govern belted wetted particles (BWPs) traveling along a specified path spontaneously. Such spontaneous particle path-finding is found to depend on the particle size and hydrophilic properties. Spontaneous particle sorting is directly realized via these discrete and distinctive paths for different particles. The deformation of the soap membrane facilitates 1D/2D particle organization along the path. This observation represents the discovery of a new spontaneous order phenomenon in soap film systems and provides a new energy-free approach for particle separation and soft colloidal crystal assembly.

7.
Nano Lett ; 24(5): 1738-1745, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38286020

RESUMEN

Rapid, sensitive, inexpensive point-of-care molecular diagnostics are crucial for the efficient control of spreading viral diseases and biosecurity of global health. However, the gold standard, polymerase chain reaction (PCR) is time-consuming and expensive and needs specialized testing laboratories. Here, we report a low-cost yet fast, selective, and sensitive Plasmonic Optical Wells-Based Enhanced Rate PCR: POWER-PCR. We optimized the efficient optofluidic design of 3D plasmonic optical wells via the computational simulation of light-to-heat conversion and thermophoretic convection in a self-created plasmonic cavity. The POWER-PCR chamber with a self-passivation layer can concentrate incident light to accumulate molecules, generate rapid heat transfer and thermophoretic flow, and minimize the quenching effect on the naked Au surface. Notably, we achieved swift photothermal cycling of nucleic acid amplification in POWER-PCR on-a-chip in 4 min 24 s. The POWER-PCR will provide an excellent solution for affordable and sensitive molecular diagnostics for precision medicine and preventive global healthcare.


Asunto(s)
Calor , Pruebas en el Punto de Atención , Simulación por Computador , Reacción en Cadena de la Polimerasa
8.
BMC Med ; 22(1): 157, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38609939

RESUMEN

BACKGROUND: Autism spectrum disorder (hereafter referred to as autism) is characterised by difficulties with (i) social communication, social interaction, and (ii) restricted and repetitive interests and behaviours. Estimates of autism prevalence within the criminal justice system (CJS) vary considerably, but there is evidence to suggest that the condition can be missed or misidentified within this population. Autism has implications for an individual's journey through the CJS, from police questioning and engagement in court proceedings through to risk assessment, formulation, therapeutic approaches, engagement with support services, and long-term social and legal outcomes. METHODS: This consensus based on professional opinion with input from lived experience aims to provide general principles for consideration by United Kingdom (UK) CJS personnel when working with autistic individuals, focusing on autistic offenders and those suspected of offences. Principles may be transferable to countries beyond the UK. Multidisciplinary professionals and two service users were approached for their input to address the effective identification and support strategies for autistic individuals within the CJS. RESULTS: The authors provide a consensus statement including recommendations on the general principles of effective identification, and support strategies for autistic individuals across different levels of the CJS. CONCLUSION: Greater attention needs to be given to this population as they navigate the CJS.


Asunto(s)
Trastorno del Espectro Autista , Trastorno Autístico , Humanos , Trastorno Autístico/diagnóstico , Trastorno Autístico/epidemiología , Trastorno Autístico/terapia , Trastorno del Espectro Autista/diagnóstico , Trastorno del Espectro Autista/epidemiología , Trastorno del Espectro Autista/terapia , Derecho Penal , Comunicación , Reino Unido/epidemiología
9.
Nat Methods ; 18(2): 212-218, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33432243

RESUMEN

Exosomes have shown great potential in disease diagnostics and therapeutics. However, current isolation approaches are burdensome and suffer from low speed, yield and purity, limiting basic research and clinical applications. Here, we describe an efficient exosome detection method via the ultrafast-isolation system (EXODUS) that allows automated label-free purification of exosomes from varied biofluids. We obtained the ultra-efficient purification of exosomes by negative pressure oscillation and double coupled harmonic oscillator-enabled membrane vibration. Our two coupled oscillators generate dual-frequency transverse waves on the membranes, enabling EXODUS to outperform other isolation techniques in speed, purity and yield. We demonstrated EXODUS by purifying exosomes from urine samples of 113 patients and validated the practical relevance in exosomal RNA profiling with the high-resolution capability and high-throughput analysis.


Asunto(s)
Exosomas , Automatización , Ensayos Analíticos de Alto Rendimiento/métodos , Humanos , ARN/aislamiento & purificación
10.
Ann Bot ; 133(1): 29-40, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-37463436

RESUMEN

BACKGROUND AND AIMS: The increased likelihood and severity of storm events has brought into focus the role of coastal ecosystems in provision of shoreline protection by attenuating wave energy. Canopy-forming kelps, including giant kelp (Macrocystis pyrifera), are thought to provide this ecosystem service, but supporting data are extremely limited. Previous in situ examinations relied mostly on comparisons between nominally similar sites with and without kelp. Given that other factors (especially seafloor bathymetry and topographic features) often differ across sites, efforts to isolate the effects of kelp on wave energy propagation confront challenges. In particular, it can be difficult to distinguish wave energy dissipation attributable to kelp from frictional processes at the seabed that often covary with the presence of kelp. Here, we use an ecological transition from no kelp to a full forest, at a single site with static bathymetry, to resolve unambiguously the capacity of giant kelp to damp waves. METHODS: We measured waves within and outside rocky reef habitat, in both the absence and the presence of giant kelp, at Marguerite Reef, Palos Verdes, CA, USA. Nested within a broader kelp restoration project, this site transitioned from a bare state to one supporting a fully formed forest (density of 8 stipes m-2). We quantified, as a function of incident wave conditions, the decline in wave energy flux attributable to the presence of kelp, as waves propagated from outside and into reef habitat. KEY RESULTS: The kelp forest damped wave energy detectably, but to a modest extent. Interactions with the seabed alone reduced wave energy flux, on average, by 12 ±â€…1.4 % over 180 m of travel. The kelp forest induced an additional 7 ±â€…1.2 % decrease. Kelp-associated declines in wave energy flux were slightly greater for waves of longer periods and smaller wave heights. CONCLUSIONS: Macrocystis pyrifera forests have a limited, albeit measurable, capacity to enhance shoreline protection from nearshore waves. Expectations that giant kelp forests, whether extant or enhanced through restoration, have substantial impacts on wave-induced coastal erosion might require re-evaluation.


Asunto(s)
Kelp , Macrocystis , Ecosistema , Bosques , Reproducción
11.
J Surg Res ; 294: 220-227, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-37913729

RESUMEN

INTRODUCTION: Clinical publications use mortality as a hard end point. It is unknown how many patient deaths are under-reported in institutional databases. The objective of this study was to query mortality in our patient cohort from our data warehouse and compare these deaths to those identified in different databases. METHODS: We passed the first/last name and date of birth of 134 patients through online mortality search engines (Find a Grave Index, US Cemetery and Funeral Home Collection, etc.) to assess their ability to capture patient deaths and compared that to deaths recorded from our institutional data warehouse. RESULTS: Our institutional data warehouse found approximately one-third of the total patient mortalities. After the Social Security Death Index, we found that the Find a Grave Index captured the most mortalities missed by the institutional data warehouse. These results highlight the advantages of incorporating readily available search engines into institutional data warehouses for the accurate collection of patient mortalities, particularly those that occur outside of index operative admission. CONCLUSIONS: The incorporation of the mortality search engines significantly augmented the capture of patient deaths. Our approach may be useful for tailored patient outreach and reporting mortalities with institutional data.


Asunto(s)
Data Warehousing , Motor de Búsqueda , Humanos , Bases de Datos Factuales
12.
Org Biomol Chem ; 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38957899

RESUMEN

Phosphatidic acid and phosphatidylserine are anionic phospholipids with emerging signalling roles in cells. Determination of how phosphatidic acid and phosphatidylserine change location and quantity in cells over time requires selective fluorescent sensors that can distinguish these two anionic phospholipids. However, the design of such synthetic sensors that can selectively bind and respond to a single phospholipid within the complex membrane milieu remains challenging. In this work, we present a simple and robust strategy to control the selectivity of synthetic sensors for phosphatidic acid and phosphatidylserine. By changing the coordination metal of a dipicolylamine (DPA) ligand from Zn(II) to Ni(II) on the same synthetic sensor with a peptide backbone, we achieve a complete switch in selectivity from phosphatidic acid to phosphatidylserine in model lipid membranes. Furthermore, this strategy was largely unaffected by the choice and the position of the fluorophores. We envision that this strategy will provide a platform for the rational design of targeted synthetic phospholipid sensors to probe plasma and intracellular membranes.

13.
Environ Sci Technol ; 58(23): 10162-10174, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38810212

RESUMEN

Residential biomass burning is an important source of black carbon (BC) exposure among rural communities in low- and middle-income countries. We collected 7165 personal BC samples and individual/household level information from 3103 pregnant women enrolled in the Household Air Pollution Intervention Network trial. Women in the intervention arm received free liquefied petroleum gas stoves and fuel throughout pregnancy; women in the control arm continued the use of biomass stoves. Median (IQR) postintervention BC exposures were 9.6 µg/m3 (5.2-14.0) for controls and 2.8 µg/m3 (1.6-4.8) for the intervention group. Using mixed models, we characterized predictors of BC exposure and assessed how exposure contrasts differed between arms by select predictors. Primary stove type was the strongest predictor (R2 = 0.42); the models including kerosene use, kitchen location, education, occupation, or stove use hours also provided additional explanatory power from the base model adjusted only for the study site. Our full, trial-wide, model explained 48% of the variation in BC exposures. We found evidence that the BC exposure contrast between arms differed by study site, adherence to the assigned study stove, and whether the participant cooked. Our findings highlight factors that may be addressed before and during studies to implement more impactful cookstove intervention trials.


Asunto(s)
Culinaria , Humanos , Femenino , Embarazo , Adulto , Contaminación del Aire Interior , Hollín , Carbono , Contaminantes Atmosféricos , Exposición a Riesgos Ambientales
14.
Nucleic Acids Res ; 50(1): 227-243, 2022 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-34928327

RESUMEN

Pseudomonas aeruginosa uses three type six secretion systems (H1-, H2- and H3-T6SS) to manipulate its environment, subvert host cells and for microbial competition. These T6SS machines are loaded with a variety of effectors/toxins, many being associated with a specific VgrG. How P. aeruginosa transcriptionally coordinates the main T6SS clusters and the multiple vgrG islands spread through the genome is unknown. Here we show an unprecedented level of control with RsmA repressing most known T6SS-related genes. Moreover, each of the H2- and H3-T6SS clusters encodes a sigma factor activator (SFA) protein called, Sfa2 and Sfa3, respectively. SFA proteins are enhancer binding proteins necessary for the sigma factor RpoN. Using a combination of RNA-seq, ChIP-seq and molecular biology approaches, we demonstrate that RpoN coordinates the T6SSs of P. aeruginosa by activating the H2-T6SS but repressing the H1- and H3-T6SS. Furthermore, RpoN and Sfa2 control the expression of the H2-T6SS-linked VgrGs and their effector arsenal to enable very effective interbacterial killing. Sfa2 is specific as Sfa3 from the H3-T6SS cannot complement loss of Sfa2. Our study further delineates the regulatory mechanisms that modulate the deployment of an arsenal of T6SS effectors likely enabling P. aeruginosa to adapt to a range of environmental conditions.


Asunto(s)
Sistemas de Secreción Bacterianos/genética , Pseudomonas aeruginosa/metabolismo , ARN Polimerasa Sigma 54/metabolismo , Sistemas de Secreción Bacterianos/metabolismo , Toxinas Bacterianas/genética , Toxinas Bacterianas/metabolismo , Regulación Bacteriana de la Expresión Génica , Pseudomonas aeruginosa/genética , ARN Polimerasa Sigma 54/genética
15.
Proc Natl Acad Sci U S A ; 118(43)2021 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-34663731

RESUMEN

The genetic origins of nanoscale extracellular vesicles in our body fluids remains unclear. Here, we perform a tracking analysis of urinary exosomes via RNA sequencing, revealing that urine exosomes mostly express tissue-specific genes for the bladder and have close cell-genetic relationships to the endothelial cell, basal cell, monocyte, and dendritic cell. Tracking the differentially expressed genes of cancers and corresponding enrichment analysis show urine exosomes are intensively involved in immune activities, indicating that they may be harnessed as reliable biomarkers of noninvasive liquid biopsy in cancer genomic diagnostics and precision medicine.


Asunto(s)
Exosomas/metabolismo , Neoplasias/patología , Orina , Humanos , Biopsia Líquida , Neoplasias/metabolismo
16.
Facial Plast Surg ; 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38052417

RESUMEN

Powered scooters, including electric scooters (e-scooters), have become an increasingly available and popular mode of personal transportation, but the health risks of these devices are poorly explored. We aim to quantify the increase in frequency of powered scooter-associated head and neck region injuries occurring yearly from 2010 to 2019, and to compare the frequency and severity of injury with those involving unpowered scooters. Here we present a retrospective cross-sectional study of all patients with head and neck injuries associated with powered and unpowered scooters seen in emergency departments reporting to the National Electronic Injury Surveillance System (NEISS) database from January 1, 2010 to December 31, 2019. During this time frame, a total of 1,620 injuries associated with powered scooters and a total of 5,675 injuries associated with unpowered scooters were reported to the NEISS. The database estimates these to reflect a nationwide total of 54,036 powered scooter-related injuries and 168,265 unpowered scooter-related injuries. Powered scooter injuries have increased for both children and adults since 2014, and estimated powered scooter injuries (16,243) surpassed estimated unpowered scooter injuries (14,124) when including all age groups for the first time in 2019. In 2019, adults are estimated to have nearly twice as many powered scooter-related head and neck injuries as children (10,884 vs. 5,359, respectively). In 2019, a higher proportion of powered scooter-related injuries involving adults were severe injuries when compared with those involving children (13.3 vs. 5.2%, respectively). Interestingly, unpowered scooters still cause many more estimated injuries in children than powered scooters did during 2019 (11,953 vs. 5,083). We find that powered scooters are now associated with a greater number and severity of head and neck injuries among the adult population than the pediatric population. But unpowered scooters still cause more head and neck injuries than powered scooters in the pediatric population.

17.
J Am Chem Soc ; 145(33): 18447-18454, 2023 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-37552123

RESUMEN

Molecular electronic spin qubits have great potential for use in quantum information science applications because their structure can be rationally tuned using synthetic chemistry. Their integration into a new class of materials, ion-paired frameworks, allows for the formation of ordered arrays of these molecular spin qubits. Three ion-paired frameworks with varying densities of paramagnetic Cu(II) porphyrins were isolated as micron-sized crystals suitable for characterization by single-crystal X-ray diffraction. Pulse-electron paramagnetic resonance (EPR) spectroscopy probed the spin coherence of these materials at temperatures up to 140 K. The crystals with the longest Cu-Cu distances had a spin-spin relaxation time (Tm) of 207 ns and a spin-lattice relaxation time (T1) of 1.8 ms at 5 K, which decreased at elevated temperature because of spin-phonon coupling. Crystals with shorter Cu-Cu distances also had lower T1 values because of enhanced cross-relaxation from qubit-qubit dipolar coupling. Frameworks with shorter Cu-Cu distances exhibited lower Tm values because of the increased interactions between qubits within the frameworks. Incorporating molecular electronic spin qubits in ion-paired frameworks enables control of composition, spacing, and interqubit interactions, providing a rational means to extend spin relaxation times.

18.
Microbiology (Reading) ; 169(7)2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37490402

RESUMEN

The life of bacteria is challenging, to endure bacteria employ a range of mechanisms to optimize their environment, including deploying the type VI secretion system (T6SS). Acting as a bacterial crossbow, this system delivers effectors responsible for subverting host cells, killing competitors and facilitating general secretion to access common goods. Due to its importance, this lethal machine has been evolutionarily maintained, disseminated and specialized to fulfil these vital functions. In fact, T6SS structural clusters are present in over 25 % of Gram-negative bacteria, varying in number from one to six different genetic clusters per organism. Since its discovery in 2006, research on the T6SS has rapidly progressed, yielding remarkable breakthroughs. The identification and characterization of novel components of the T6SS, combined with biochemical and structural studies, have revealed fascinating mechanisms governing its assembly, loading, firing and disassembly processes. Recent findings have also demonstrated the efficacy of this system against fungal and Gram-positive cells, expanding its scope. Ongoing research continues to uncover an extensive and expanding repertoire of T6SS effectors, the genuine mediators of T6SS function. These studies are shedding light on new aspects of the biology of prokaryotic and eukaryotic organisms. This review provides a comprehensive overview of the T6SS, highlighting recent discoveries of its structure and the diversity of its effectors. Additionally, it injects a personal perspective on avenues for future research, aiming to deepen our understanding of this combative system.


Asunto(s)
Proteínas Bacterianas , Sistemas de Secreción Tipo VI , Proteínas Bacterianas/genética , Bacterias/genética , Sistemas de Secreción Tipo VI/genética , Bacterias Gramnegativas/genética , Eucariontes
19.
Nat Mater ; 21(5): 540-546, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35332292

RESUMEN

Precise and selective manipulation of colloids and biological cells has long been motivated by applications in materials science, physics and the life sciences. Here we introduce our harmonic acoustics for a non-contact, dynamic, selective (HANDS) particle manipulation platform, which enables the reversible assembly of colloidal crystals or cells via the modulation of acoustic trapping positions with subwavelength resolution. We compose Fourier-synthesized harmonic waves to create soft acoustic lattices and colloidal crystals without using surface treatment or modifying their material properties. We have achieved active control of the lattice constant to dynamically modulate the interparticle distance in a high-throughput (>100 pairs), precise, selective and reversible manner. Furthermore, we apply this HANDS platform to quantify the intercellular adhesion forces among various cancer cell lines. Our biocompatible HANDS platform provides a highly versatile particle manipulation method that can handle soft matter and measure the interaction forces between living cells with high sensitivity.


Asunto(s)
Acústica , Coloides , Coloides/química , Ciencia de los Materiales
20.
Mol Cell Biochem ; 478(8): 1825-1833, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36574099

RESUMEN

Diabetic patients often have impaired heart rate (HR) control. HR is regulated both intrinsically within the sinoatrial node (SAN) and via neuronal input. Previously, we found lower ex vivo HR in type 2 diabetic rat hearts, suggesting impaired HR generation within the SAN. The major driver of pacemaking within the SAN is the activity of hyperpolarisation-activated cyclic nucleotide-gated 4 (HCN(4)) channels. This study aimed to investigate whether the lower intrinsic HR in the type 2 diabetic heart is due to changes in HCN4 function, protein expression and/ or distribution. The intrinsic HR response to HCN4 blockade was determined in isolated Langendorff-perfused hearts of Zucker type 2 Diabetic Fatty (ZDF) rats (DM) and their non-diabetic ZDF littermates (nDM). HCN4 protein expression and membrane localisation were determined using western blot and immunofluorescence, respectively. We found that the intrinsic HR was lower in DM compared to nDM hearts. The change in intrinsic HR in response to HCN4 blockade with ivabradine was diminished in DM hearts, which normalised the intrinsic HR between the groups. HCN4 protein expression was decreased in the SAN of DM compared to nDM controls with no change in the fraction of HCN4 localised to the membrane of SAN cardiomyocytes. The lower intrinsic HR in DM is likely due to decreased HCN4 expression and depressed HCN4 function. Our study provides a novel understanding into the intrinsic mechanisms underlying altered HR control in type 2 diabetes.


Asunto(s)
Diabetes Mellitus Tipo 2 , Nodo Sinoatrial , Ratas , Animales , Nodo Sinoatrial/metabolismo , Canales Regulados por Nucleótidos Cíclicos Activados por Hiperpolarización/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Ratas Zucker , Miocitos Cardíacos/metabolismo , Canales de Potasio/metabolismo
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