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1.
N Engl J Med ; 387(2): 148-159, 2022 07 14.
Artículo en Inglés | MEDLINE | ID: mdl-35830641

RESUMEN

BACKGROUND: Neonatal hypoxic-ischemic encephalopathy is an important cause of death as well as long-term disability in survivors. Erythropoietin has been hypothesized to have neuroprotective effects in infants with hypoxic-ischemic encephalopathy, but its effects on neurodevelopmental outcomes when given in conjunction with therapeutic hypothermia are unknown. METHODS: In a multicenter, double-blind, randomized, placebo-controlled trial, we assigned 501 infants born at 36 weeks or more of gestation with moderate or severe hypoxic-ischemic encephalopathy to receive erythropoietin or placebo, in conjunction with standard therapeutic hypothermia. Erythropoietin (1000 U per kilogram of body weight) or saline placebo was administered intravenously within 26 hours after birth, as well as at 2, 3, 4, and 7 days of age. The primary outcome was death or neurodevelopmental impairment at 22 to 36 months of age. Neurodevelopmental impairment was defined as cerebral palsy, a Gross Motor Function Classification System level of at least 1 (on a scale of 0 [normal] to 5 [most impaired]), or a cognitive score of less than 90 (which corresponds to 0.67 SD below the mean, with higher scores indicating better performance) on the Bayley Scales of Infant and Toddler Development, third edition. RESULTS: Of 500 infants in the modified intention-to-treat analysis, 257 received erythropoietin and 243 received placebo. The incidence of death or neurodevelopmental impairment was 52.5% in the erythropoietin group and 49.5% in the placebo group (relative risk, 1.03; 95% confidence interval [CI], 0.86 to 1.24; P = 0.74). The mean number of serious adverse events per child was higher in the erythropoietin group than in the placebo group (0.86 vs. 0.67; relative risk, 1.26; 95% CI, 1.01 to 1.57). CONCLUSIONS: The administration of erythropoietin to newborns undergoing therapeutic hypothermia for hypoxic-ischemic encephalopathy did not result in a lower risk of death or neurodevelopmental impairment than placebo and was associated with a higher rate of serious adverse events. (Funded by the National Institute of Neurological Disorders and Stroke; ClinicalTrials.gov number, NCT02811263.).


Asunto(s)
Eritropoyetina , Hipotermia Inducida , Hipoxia-Isquemia Encefálica , Fármacos Neuroprotectores , Administración Intravenosa , Parálisis Cerebral/etiología , Método Doble Ciego , Eritropoyetina/administración & dosificación , Eritropoyetina/efectos adversos , Eritropoyetina/uso terapéutico , Humanos , Hipotermia Inducida/métodos , Hipoxia-Isquemia Encefálica/complicaciones , Hipoxia-Isquemia Encefálica/tratamiento farmacológico , Hipoxia-Isquemia Encefálica/terapia , Lactante , Recién Nacido , Fármacos Neuroprotectores/administración & dosificación , Fármacos Neuroprotectores/efectos adversos , Fármacos Neuroprotectores/uso terapéutico
2.
Proc Natl Acad Sci U S A ; 119(39): e2206292119, 2022 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-36122222

RESUMEN

Understanding the pathways by which simple RNA viruses self-assemble from their coat proteins and RNA is of practical and fundamental interest. Although RNA-protein interactions are thought to play a critical role in the assembly, our understanding of their effects is limited because the assembly process is difficult to observe directly. We address this problem by using interferometric scattering microscopy, a sensitive optical technique with high dynamic range, to follow the in vitro assembly kinetics of more than 500 individual particles of brome mosaic virus (BMV)-for which RNA-protein interactions can be controlled by varying the ionic strength of the buffer. We find that when RNA-protein interactions are weak, BMV assembles by a nucleation-and-growth pathway in which a small cluster of RNA-bound proteins must exceed a critical size before additional proteins can bind. As the strength of RNA-protein interactions increases, the nucleation time becomes shorter and more narrowly distributed, but the time to grow a capsid after nucleation is largely unaffected. These results suggest that the nucleation rate is controlled by RNA-protein interactions, while the growth process is driven less by RNA-protein interactions and more by protein-protein interactions and intraprotein forces. The nucleated pathway observed with the plant virus BMV is strikingly similar to that previously observed with bacteriophage MS2, a phylogenetically distinct virus with a different host kingdom. These results raise the possibility that nucleated assembly pathways might be common to other RNA viruses.


Asunto(s)
Bromovirus , Virus ARN , Bromovirus/genética , Bromovirus/metabolismo , Cápside/metabolismo , Virus ARN/genética , ARN Viral/genética , ARN Viral/metabolismo , Virión/genética , Virión/metabolismo
3.
Clin Infect Dis ; 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38913574

RESUMEN

BACKGROUND: Few antiviral therapies have been studied in patients with COVID-19 and kidney impairment. Herein, efficacy, safety, and pharmacokinetics of remdesivir, its metabolites, and sulfobutylether-beta-cyclodextrin excipient were evaluated in hospitalized patients with COVID-19 and severe kidney impairment. METHODS: In REDPINE, a phase 3, randomized, double-blind, placebo-controlled study, participants aged ≥12 years hospitalized for COVID-19 pneumonia with acute kidney injury (AKI), chronic kidney disease (CKD), or kidney failure were randomized 2:1 to receive intravenous remdesivir (200 mg on Day 1; 100 mg daily up to Day 5) or placebo (enrollment: March 2021-March 2022). The primary efficacy endpoint was the composite of all-cause mortality or invasive mechanical ventilation (IMV) through Day 29. Safety was evaluated through Day 60. RESULTS: Although enrollment concluded early, 243 participants were enrolled and treated (remdesivir, n = 163; placebo, n = 80). At baseline, 90 (37.0%) participants had AKI (remdesivir, 60; placebo, 30), 64 (26.3%) had CKD (remdesivir, 44; placebo, 20), and 89 (36.6%) had kidney failure (remdesivir, 59; placebo, 30); 31 (12.8%) were COVID-19 vaccinated. Composite all-cause mortality or IMV through Day 29 was 29.4% and 32.5% in the remdesivir and placebo group, respectively (P = 0.61). Treatment-emergent adverse events were reported in 80.4% versus 77.5% and serious adverse events in 50.3% versus 50.0% of participants who received remdesivir versus placebo, respectively. Pharmacokinetic plasma exposure to remdesivir was not affected by kidney function. CONCLUSIONS: Although underpowered, no significant difference in efficacy was observed between treatment groups. REDPINE demonstrated that remdesivir is safe in those with COVID-19 and severe kidney impairment. (EudraCT number: 2020-005416-22; Clinical Trials.gov number: NCT04745351). TRIAL REGISTRATION: EudraCT number: 2020-005416-22; Clinical Trials.gov number: NCT04745351.

4.
Br J Haematol ; 204(4): 1507-1514, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38323352

RESUMEN

The occurrence and severity of osteonecrosis in sickle cell anaemia (SCA) vary due to risk factors, including genetic modifiers. Bone morphogenetic proteins (BMPs), particularly BMP6, and the vitamin D receptor (VDR) play key roles in cartilage and bone metabolism, making them potential contributors to orthopaedic outcomes in SCA. Here, we evaluated the association of polymorphisms in BMP6 (rs3812163, rs270393 and rs449853) and VDR (FokI rs2228570 and Cdx2 rs11568820) genes with osteonecrosis risk in a Brazilian SCA cohort. A total of 177 unrelated SCA patients were selected. The AA genotype of BMP6 rs3812163 was independently associated with a lower osteonecrosis risk (p = 0.015; odds ratio (OR): 0.38; 95% confidence interval (CI): 0.18-0.83) and with the long-term cumulative incidence of osteonecrosis (p = 0.029; hazard ratio: 0.56, 95% CI: 0.34-0.94). The VDR rs2228570 TT genotype was independently associated with a lower osteonecrosis risk (p = 0.039; OR: 0.14; 95% CI: 0.02-0.90). In summary, our results provide evidence that BMP6 rs3812163 and the VDR rs2228570 might be implicated in osteonecrosis pathophysiology in SCA and might help identify individuals at high risk.


Asunto(s)
Anemia de Células Falciformes , Osteonecrosis , Humanos , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple , Factores de Riesgo , Osteonecrosis/genética , Anemia de Células Falciformes/complicaciones , Anemia de Células Falciformes/genética , Genotipo , Estudios de Casos y Controles , Proteína Morfogenética Ósea 6/genética , Receptores de Calcitriol/genética
5.
Mamm Genome ; 35(2): 186-200, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38480585

RESUMEN

Approximately 80% of the world's cattle are raised in regions with a high risk of tick-borne diseases, resulting in significant economic losses due to parasitism by Rhipicephalus (Boophilus) microplus. However, the lack of a systemic biology approach hampers a comprehensive understanding of tick-host interactions that mediate tick resistance phenotypes. Here, we conducted a genome-wide association study (GWAS) of 2933 Braford cattle and found 340 single-nucleotide polymorphisms (SNPs) associated with tick counts. Gene expression analyses were performed on skin samples obtained from previously tick-exposed heifers with extremely high or low estimated breeding values for R. microplus counts. Evaluations were performed both before and after artificial infestation with ticks. Differentially expressed genes were found within 1-Mb windows centered at significant SNPs from GWAS. A total of 330 genes were related to the breakdown of homeostasis that was induced by larval attachment to bovine skin. Enrichment analysis pointed to a key role of proteolysis and signal transduction via JAK/STAT, NFKB and WNT/beta catenin signaling pathways. Integrative analysis on matrixEQTL revealed two cis-eQTLs and four significant SNPs in the genes peptidyl arginine deiminase type IV (PADI4) and LOC11449251. The integration of genomic data from QTL maps and transcriptome analyses has identified a set of twelve key genes that show significant associations with tick loads. These genes could be key candidates to improve the accuracy of genomic predictions for tick resistance in Braford cattle.


Asunto(s)
Resistencia a la Enfermedad , Estudio de Asociación del Genoma Completo , Polimorfismo de Nucleótido Simple , Rhipicephalus , Infestaciones por Garrapatas , Animales , Bovinos , Rhipicephalus/genética , Rhipicephalus/fisiología , Infestaciones por Garrapatas/veterinaria , Infestaciones por Garrapatas/genética , Infestaciones por Garrapatas/parasitología , Infestaciones por Garrapatas/inmunología , Resistencia a la Enfermedad/genética , Biología de Sistemas , Enfermedades de los Bovinos/genética , Enfermedades de los Bovinos/inmunología , Enfermedades de los Bovinos/parasitología , Sitios de Carácter Cuantitativo , Femenino , Interacciones Huésped-Parásitos/genética , Interacciones Huésped-Parásitos/inmunología
6.
Planta ; 260(1): 4, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38775846

RESUMEN

MAIN CONCLUSION: Natural selection influenced adaptive divergence between Cereus fernambucensis and Cereus insularis, revealing key genes governing abiotic stress responses and supporting neoteny in C. insularis. Uncovering the molecular mechanisms driving adaptive divergence in traits related to habitat adaptation remains a central challenge. In this study, we focused on the cactus clade, which includes Cereus sericifer F.Ritter, Cereus fernambucensis Lem., and Cereus insularis Hemsley. These allopatric species inhabit distinct relatively drier regions within the Brazilian Atlantic Forest, each facing unique abiotic conditions. We leveraged whole transcriptome data and abiotic variables datasets to explore lineage-specific and environment-specific adaptations in these species. Employing comparative phylogenetic methods, we identified genes under positive selection (PSG) and examined their association with non-synonymous genetic variants and abiotic attributes through a PhyloGWAS approach. Our analysis unveiled signatures of selection in all studied lineages, with C. fernambucensis northern populations and C. insularis showing the most PSGs. These PSGs predominantly govern abiotic stress regulation, encompassing heat tolerance, UV stress response, and soil salinity adaptation. Our exclusive observation of gene expression tied to early developmental stages in C. insularis supports the hypothesis of neoteny in this species. We also identified genes associated with abiotic variables in independent lineages, suggesting their role as environmental filters on genetic diversity. Overall, our findings suggest that natural selection played a pivotal role in the geographic range of these species in response to environmental and biogeographic transitions.


Asunto(s)
Adaptación Fisiológica , Cactaceae , Bosques , Perfilación de la Expresión Génica , Filogenia , Brasil , Cactaceae/genética , Cactaceae/fisiología , Adaptación Fisiológica/genética , Selección Genética , Transcriptoma , Estrés Fisiológico/genética , Regulación de la Expresión Génica de las Plantas
7.
J Pediatr ; 266: 113853, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38006967

RESUMEN

OBJECTIVE: To determine if time to reaching target temperature (TT) is associated with death or neurodevelopmental impairment (NDI) at 2 years of age in infants with hypoxic-ischemic encephalopathy (HIE). STUDY DESIGN: Newborn infants ≥36 weeks of gestation diagnosed with moderate or severe HIE and treated with therapeutic hypothermia were stratified based on time at which TT was reached, defined as early (ie, ≤4 hours of age) or late (>4 hours of age). Primary outcomes were death or NDI. Secondary outcomes included neurodevelopmental assessment with Bayley Scales of Infant and Toddler Development, third edition (BSID-III) at age 2. RESULTS: Among 500 infants, the median time to reaching TT was 4.3 hours (IWR, 3.2-5.7 hours). Infants in early TT group (n = 211 [42%]) compared with the late TT group (n = 289 [58%]) were more likely to be inborn (23% vs 13%; P < .001) and have severe HIE (28% vs 19%; P = .03). The early and late TT groups did not differ in the primary outcome of death or any NDI (adjusted RR, 1.05; 95% CI, 0.85-0.30; P = .62). Among survivors, neurodevelopmental outcomes did not differ significantly in the 2 groups (adjusted mean difference in Bayley Scales of Infant Development-III scores: cognitive, -2.8 [95% CI, -6.1 to 0.5], language -3.3 [95% CI, -7.4 to 0.8], and motor -3.5 [95% CI, -7.3 to 0.3]). CONCLUSIONS: In infants with HIE, time to reach TT is not independently associated with risk of death or NDI at age 2 years. Among survivors, developmental outcomes are similar between those who reached TT at <4 and ≥4 hours of age. TRIAL REGISTRATION: High-dose Erythropoietin for Asphyxia and Encephalopathy (HEAL); NCT02811263; https://beta. CLINICALTRIALS: gov/study/NCT02811263.


Asunto(s)
Hipotermia Inducida , Hipoxia-Isquemia Encefálica , Humanos , Recién Nacido , Frío , Discapacidades del Desarrollo/complicaciones , Hipoxia-Isquemia Encefálica/terapia , Hipoxia-Isquemia Encefálica/complicaciones , Temperatura
8.
PLoS Comput Biol ; 19(6): e1011176, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37343029

RESUMEN

The broad receptive field of the olfactory receptors constitutes the basis of a combinatorial code that allows animals to detect and discriminate many more odorants than the actual number of receptor types that they express. One drawback is that high odor concentrations recruit lower affinity receptors which can lead to the perception of qualitatively different odors. Here we addressed the contribution that signal-processing in the antennal lobe makes to reduce concentration dependence in odor representation. By means of calcium imaging and pharmacological approach we describe the contribution that GABA receptors play in terms of the amplitude and temporal profiles of the signals that convey odor information from the antennal lobes to higher brain centers. We found that GABA reduces the amplitude of odor elicited signals and the number of glomeruli that are recruited in an odor-concentration-dependent manner. Blocking GABA receptors decreases the correlation among glomerular activity patterns elicited by different concentrations of the same odor. In addition, we built a realistic mathematical model of the antennal lobe that was used to test the viability of the proposed mechanisms and to evaluate the processing properties of the AL network under conditions that cannot be achieved in physiology experiments. Interestingly, even though based on a rather simple topology and cell interactions solely mediated by GABAergic lateral inhibitions, the AL model reproduced key features of the AL response upon different odor concentrations and provides plausible solutions for concentration invariant recognition of odors by artificial sensors.


Asunto(s)
Neuronas Receptoras Olfatorias , Receptores Odorantes , Animales , Odorantes , Olfato/fisiología , Neuronas Receptoras Olfatorias/fisiología , Receptores Odorantes/metabolismo , Receptores de GABA , Vías Olfatorias/fisiología
9.
Eur J Haematol ; 113(2): 172-182, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38634725

RESUMEN

OBJECTIVES: Sickle cell disease (SCD) is an inherited disorder that causes lifelong complications, substantially impacting the physical and emotional well-being of patients and their caregivers. Studies investigating the effects of SCD on quality of life (QOL) are often limited to individual countries, lack SCD-specific QOL questionnaires, and exclude the caregiver experience. The SHAPE survey aimed to broaden the understanding of the global burden of SCD on patients and their caregivers and to capture the viewpoint of healthcare providers (HCPs). METHODS: A total of 919 patients, 207 caregivers, and 219 HCPs from 10, 9, and 8 countries, respectively, answered a series of closed-ended questions about their experiences with SCD. RESULTS: The symptoms most frequently reported by patients were fatigue/tiredness (84%) and pain/vaso-occlusive crises (71%). Patients' fatigue/tiredness had one of the greatest impacts on both patients' and caregivers' QOL. On average, patients and caregivers reported missing 7.5 days and 5.0 days per month, respectively, of school or work. HCPs reported a need for effective tools to treat fatigue/tiredness and a desire for more support to educate patients on long-term SCD-related health risks. CONCLUSIONS: The multifaceted challenges identified using the SHAPE survey highlight the global need to improve both patient and caregiver QOL.


Asunto(s)
Anemia de Células Falciformes , Cuidadores , Personal de Salud , Calidad de Vida , Humanos , Anemia de Células Falciformes/psicología , Anemia de Células Falciformes/epidemiología , Anemia de Células Falciformes/terapia , Cuidadores/psicología , Adulto , Personal de Salud/psicología , Adolescente , Masculino , Femenino , Encuestas y Cuestionarios , Adulto Joven , Costo de Enfermedad , Conocimientos, Actitudes y Práctica en Salud , Persona de Mediana Edad
10.
Nanomedicine ; : 102770, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38960365

RESUMEN

Gadolinium-based contrast agents (GBCAs) are used in around 40 % of MRI procedures. Despite initial perceptions of minimal risk, their long-term use has emphasized the need to reduce toxicity and develop more efficient GBCAs with extended blood retention. Advancements in nanomaterials have led to improved GBCAs, enhancing MRI diagnostics. This study synthesizes and characterizes nanostructured gadolinium(III) micelles as superior MRI contrast agents. The complexes, [Gd(L)2], where L is a ligand of the N-alkyl-N-methylglucamine surfactant series (L8, L10 or L12, L10), form nanostructured micelles in aqueous solution. Gd(L8)2 and Gd(L10)2 relaxivities remained stable across concentrations. Compared to Gd-DTPA, Gd(III) micelles showed enhanced T1-weighted MRI contrast. Gd(L12)2 micelles exhibited cytotoxicity against B16F10 melanoma cells (IC50 42.5 ±â€¯2.2 µM) and L292L929 fibroblasts (IC50 52.0 ±â€¯2.5 µM), with a selectivity index of 1.2. In vivo application in mice brain T2-weighted images suggests nanostructured Gd(III) micelles are promising MRI contrast agents for targeting healthy organs or tumors.

11.
An Acad Bras Cienc ; 96(2): e20231145, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38747798

RESUMEN

Elephantgrass stands out for its high potential for forage production in different tropical and subtropical regions. In most properties, it is cultivated intensively with high doses of mineral fertilizers, mainly nitrogen, which makes production expensive and less sustainable. In this context, the mixtures of elephantgrass with forage legumes can make the system more efficient and with less environmental impact. Thus, the objective is to evaluate elephantgrass-based grazing systems,with or without a legume in terms of sward characteristics, herbage accumulation and nutritional value of pastures during one, agricultural year. Two grazing systems (treatments) were analyzed: (i) elephantgrass-based (EG) with mixed spontaneous-growing species (SGE) in the warm-season and ryegrass (R) in the cool-season; and (ii) EG + SGE + R + pinto peanut. The standardization criterion between the systems was the level of nitrogen fertilization (120 kg N/ha/year). The presence of pinto peanut positively affected the botanical composition of the pasture, with a reduction in SGE and dead material, and in the morphology of elephantgrass, with a greater proportion of leaf blades, and less stem + sheath and senescent material. In themixture with pinto peanut, there was an increase in herbage accumulation and greater nutritional value of forage.


Asunto(s)
Arachis , Valor Nutritivo , Estaciones del Año , Arachis/química , Fertilizantes/análisis , Nitrógeno/análisis , Nitrógeno/metabolismo , Agricultura/métodos , Lolium
12.
Chaos ; 34(5)2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38717396

RESUMEN

This study investigates the dynamics of a modified Colpitts oscillator, exhibiting complex periodic and chaotic behaviors. Our research explores the dynamics and synchronization of coupled chaotic Colpitts oscillators, crucial for understanding their potential applications and behaviors. The main discovery is the emergence of a phase in which the systems achieve either complete synchronization or desynchronization. This behavior depends on the values of the coupling parameter. The subsequent challenge involves understanding how the coupling parameter influences the emergence of this synchronization phenomenon.

13.
J Anim Breed Genet ; 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38853664

RESUMEN

This study utilized Bayesian inference in a genome-wide association study (GWAS) to identify genetic markers associated with traits relevant to the adaptation of Hereford and Braford cattle breeds. We focused on eye pigmentation (EP), weaning hair coat (WHC), yearling hair coat (YHC), and breeding standard (BS). Our dataset comprised 126,290 animals in the pedigree. Out of these, 233 sires were genotyped using high-density (HD) chips, and 3750 animals with medium-density (50 K) single-nucleotide polymorphism (SNP) chips. Employing the Bayes B method with a prior probability of π = 0.99, we identified and tagged single nucleotide polymorphisms (Tag SNPs), ranging from 18 to 117 SNPs depending on the trait. These Tag SNPs facilitated the construction of reduced SNP panels. We then evaluated the predictive accuracy of these panels in comparison to traditional medium-density SNP chips. The accuracy of genomic predictions using these reduced panels varied significantly depending on the clustering method, ranging from 0.13 to 0.65. Additionally, we conducted functional enrichment analysis that found genes associated with the most informative SNP markers in the current study, thereby providing biological insights into the genomic basis of these traits.

14.
J Stroke Cerebrovasc Dis ; 33(1): 107474, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38006767

RESUMEN

OBJECTIVES: Stroke is a devastating clinical outcome that significantly contributes to the morbidity and mortality of sickle cell anemia (SCA) patients. Despite its advantages in predicting stroke risk, transcranial Doppler screening has limitations that restrict its applicability, highlighting the need for emerging prognostic tools. Thrombospondin-1 plays a crucial role in endothelial injury, platelet adhesion, and nitric oxide metabolism and may be implicated in stroke pathophysiology. Here, we aimed to evaluate the association of THBS1 genetic variations with the occurrence of stroke in SCA patients MATERIALS AND METHODS: By real-time PCR, 512 SCA patients were fully genotyped for THBS1 A-296G (rs1478605) polymorphism RESULTS: THBS1 GG genotype was associated with a lower risk for stroke occurrence [odds ratio (OR): 0.30; 95% confidence interval (CI): 0.11-0.78; P = 0.011], although these findings were not consistent with multivariate logistic regression analysis (OR: 0.73, 95% CI: 0.12 - 4.37; P = 0.736). In agreement, the cumulative incidence of stroke for patients with AG/AA genotypes was higher when compared to the GG genotype (P = 0.018). However, the association was not maintained in the multivariate proportional hazards model (hazard ratio: 0.67, 95% CI: 0.12-3.61; P = 0.643) CONCLUSIONS: In summary, the present study shows that the THBS1 A-296G (rs1478605) polymorphism may be a potential modifier for stroke in SCA.


Asunto(s)
Anemia de Células Falciformes , Accidente Cerebrovascular , Humanos , Anemia de Células Falciformes/complicaciones , Anemia de Células Falciformes/diagnóstico , Anemia de Células Falciformes/epidemiología , Brasil/epidemiología , Genotipo , Polimorfismo Genético , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/genética
15.
Gut ; 72(5): 896-905, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36881441

RESUMEN

OBJECTIVE: Faecal microbiota transplantation (FMT) in germ-free (GF) mice is a common approach to study the causal role of the gut microbiota in metabolic diseases. Lack of consideration of housing conditions post-FMT may contribute to study heterogeneity. We compared the impact of two housing strategies on the metabolic outcomes of GF mice colonised by gut microbiota from mice treated with a known gut modulator (cranberry proanthocyanidins (PAC)) or vehicle. DESIGN: High-fat high-sucrose diet-fed GF mice underwent FMT-PAC colonisation in sterile individual positive flow ventilated cages under rigorous housing conditions and then maintained for 8 weeks either in the gnotobiotic-axenic sector or in the specific pathogen free (SPF) sector of the same animal facility. RESULTS: Unexpectedly, 8 weeks after colonisation, we observed opposing liver phenotypes dependent on the housing environment of mice. Mice housed in the GF sector receiving the PAC gut microbiota showed a significant decrease in liver weight and hepatic triglyceride accumulation compared with control group. Conversely, exacerbated liver steatosis was observed in the FMT-PAC mice housed in the SPF sector. These phenotypic differences were associated with housing-specific profiles of colonising bacterial in the gut and of faecal metabolites. CONCLUSION: These results suggest that the housing environment in which gnotobiotic mice are maintained post-FMT strongly influences gut microbiota composition and function and can lead to distinctive phenotypes in recipient mice. Better standardisation of FMT experiments is needed to ensure reproducible and translatable results.


Asunto(s)
Vivienda , Microbiota , Animales , Ratones , Calidad de la Vivienda , Obesidad/metabolismo , Trasplante de Microbiota Fecal , Fenotipo , Dieta Alta en Grasa/efectos adversos , Vida Libre de Gérmenes , Ratones Endogámicos C57BL
16.
Gut ; 72(3): 460-471, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36008102

RESUMEN

OBJECTIVE: Bariatric surgery is an effective treatment for type 2 diabetes (T2D) that changes gut microbial composition. We determined whether the gut microbiota in humans after restrictive or malabsorptive bariatric surgery was sufficient to lower blood glucose. DESIGN: Women with obesity and T2D had biliopancreatic diversion with duodenal switch (BPD-DS) or laparoscopic sleeve gastrectomy (LSG). Faecal samples from the same patient before and after each surgery were used to colonise rodents, and determinants of blood glucose control were assessed. RESULTS: Glucose tolerance was improved in germ-free mice orally colonised for 7 weeks with human microbiota after either BPD-DS or LSG, whereas food intake, fat mass, insulin resistance, secretion and clearance were unchanged. Mice colonised with microbiota post-BPD-DS had lower villus height/width and crypt depth in the distal jejunum and lower intestinal glucose absorption. Inhibition of sodium-glucose cotransporter (Sglt)1 abrogated microbiota-transmissible improvements in blood glucose control in mice. In specific pathogen-free (SPF) rats, intrajejunal colonisation for 4 weeks with microbiota post-BPD-DS was sufficient to improve blood glucose control, which was negated after intrajejunal Sglt-1 inhibition. Higher Parabacteroides and lower Blautia coincided with improvements in blood glucose control after colonisation with human bacteria post-BPD-DS and LSG. CONCLUSION: Exposure of rodents to human gut microbiota after restrictive or malabsorptive bariatric surgery improves glycaemic control. The gut microbiota after bariatric surgery is a standalone factor that alters upper gut intestinal morphology and lowers Sglt1-mediated intestinal glucose absorption, which improves blood glucose control independently from changes in obesity, insulin or insulin resistance.


Asunto(s)
Cirugía Bariátrica , Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Resistencia a la Insulina , Obesidad Mórbida , Humanos , Femenino , Ratas , Ratones , Animales , Glucosa , Diabetes Mellitus Tipo 2/cirugía , Obesidad/cirugía , Gastrectomía , Obesidad Mórbida/cirugía
17.
J Am Chem Soc ; 145(18): 10007-10014, 2023 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-37097728

RESUMEN

As part of our exploration of plutonium-containing materials as potential nuclear waste forms, we report the first extended structure Pu(V) material and the first Pu(V) borate. Crystals of Na2(PuO2)(BO3) were grown out of mixed hydroxide/boric acid flux and found to crystallize in the orthorhombic space group Cmcm with lattice parameters of a = 9.9067(4) Å, b = 6.5909(2) Å, and c = 6.9724(2) Å. Na2(PuO2)(BO3) adopts a layered structure in which layers of PuO2(BO3)2- are separated by sodium cations. Plutonium is found in a pentagonal bipyramidal coordination environment, with axial Pu(V)-O plutonyl bond lengths of 1.876(3) Å and equatorial Pu-O bond lengths ranging from 2.325(5) to 2.467(3) Å. We find that the Pu(V)-O plutonyl bond lengths are approximately 0.1 Å longer than the reported Pu(VI)-O plutonyl bond lengths and shorter by approximately 0.033 Å than the corresponding U(V) uranyl bond lengths. Raman spectroscopy on single crystals was used to determine the PuO2+ plutonyl stretching and the equatorial breathing mode frequencies of the pentagonal bipyramidal coordination environment around plutonium. Density functional theory calculations were used to calculate the Raman spectrum to help identify the Raman bands at 690 and 630 cm-1 as corresponding to the plutonyl(V) ν1 stretch and the equatorial PuO5 breathing mode, respectively. UV-vis measurements on single crystals indicate semiconducting behavior with a band gap of ∼2.60 eV.

18.
Br J Haematol ; 202(3): 657-668, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37011913

RESUMEN

Haemoglobin S polymerization in the red blood cells (RBCs) of individuals with sickle cell anaemia (SCA) can cause RBC sickling and cellular alterations. Piezo1 is a mechanosensitive protein that modulates intracellular calcium (Ca2+ ) influx, and its activation has been associated with increased RBC surface membrane phosphatidylserine (PS) exposure. Hypothesizing that Piezo1 activation, and ensuing Gárdos channel activity, alter sickle RBC properties, RBCs from patients with SCA were incubated with the Piezo1 agonist, Yoda1 (0.1-10 µM). Oxygen-gradient ektacytometry and membrane potential measurement showed that Piezo1 activation significantly decreased sickle RBC deformability, augmented sickling propensity, and triggered pronounced membrane hyperpolarization, in association with Gárdos channel activation and Ca2+ influx. Yoda1 induced Ca2+ -dependent adhesion of sickle RBCs to laminin, in microfluidic assays, mediated by increased BCAM binding affinity. Furthermore, RBCs from SCA patients that were homo-/heterozygous for the rs59446030 gain-of-function Piezo1 variant demonstrated enhanced sickling under deoxygenation and increased PS exposure. Thus, Piezo1 stimulation decreases sickle RBC deformability, and increases the propensities of these cells to sickle upon deoxygenation and adhere to laminin. Results support a role of Piezo1 in some of the RBC properties that contribute to SCA vaso-occlusion, indicating that Piezo1 may represent a potential therapeutic target molecule for this disease.


Asunto(s)
Anemia de Células Falciformes , Calcio , Humanos , Calcio/metabolismo , Laminina/metabolismo , Eritrocitos/metabolismo , Eritrocitos Anormales/metabolismo
19.
J Pediatr ; 258: 113400, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37019334

RESUMEN

OBJECTIVE: To assess whether high dose erythropoietin (Epo) treatment of cooled infants with neonatal hypoxic ischemic encephalopathy results in a higher risk of prespecified serious adverse events (SAEs). STUDY DESIGN: Five hundred infants born at ≥36 weeks of gestation with moderate or severe hypoxic ischemic encephalopathy undergoing therapeutic hypothermia were randomized to Epo or placebo on days 1, 2, 3, 4, and 7. Pretreatment and posttreatment SAEs were compared with adjusted generalized linear models, with posttreatment models adjusted for the presence of a pretreatment SAE. Clinical risk factors and potential mechanisms for SAEs were also examined. RESULTS: The rate of experiencing at least one posttreatment SAE did not significantly differ between groups (adjusted relative risk [aRR], 95% CI: 1.17, 0.92-1.49); however, posttreatment thrombosis was identified more often in the Epo group (n = 6, 2.3%) than the placebo group (n = 1, 0.4%; aRR, 95% CI: 5.09, 1.32-19.64). The rate of posttreatment intracranial hemorrhage identified at the treatment sites by either ultrasound or magnetic resonance imaging was slightly elevated in the Epo group (n = 61, 24%) but not significantly different from the placebo group (n = 46, 19%; aRR, 95% CI: 1.21, 0.85, 1.72). CONCLUSIONS: A small increased risk of major thrombotic events was identified in the Epo treatment group. TRIAL REGISTRATION: NCT02811263.


Asunto(s)
Eritropoyetina , Hipotermia Inducida , Hipoxia-Isquemia Encefálica , Recién Nacido , Lactante , Humanos , Hipoxia-Isquemia Encefálica/complicaciones , Eritropoyetina/efectos adversos , Hipotermia Inducida/efectos adversos , Hipotermia Inducida/métodos , Frío
20.
Milbank Q ; 101(3): 975-998, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37082794

RESUMEN

Policy Points There need to be sweeping changes to medical school curricula that addresses structural racism in medicine and how to attend to this in medical practice. The Liaison Committee on Medical Education should develop and promulgate specific learning objectives and curricular offerings that require medical schools to teach about structural racism and antiracist medical practice in ways that are robust and standardized. The federal government, through the Health Resources and Services Administration, should prioritize support for antiracism education in medical schools, residency, and continuing medical education in similar ways and with similar effort in scale and scope to its support for primary care, providing technical assistance and grants for programs across the educational spectrum that provide antiracist training. State governments should mandate, as part of continuing education requirements for physicians, 2 or more hours per recertification cycle of antiracist training. CONTEXT: Since the beginning of COVID-19 and the rise of social justice movements sparked by the murders of George Floyd and Breonna Taylor in the summer of 2020, many medical schools have made public statements committing themselves to become antiracist institutions. The notions that US society generally, and medicine, are rife with structural racism no longer seems as controversial in the academic community. Challenges remain, however, in how this basic understanding gets translated into medical education practice. Understanding where the profession must go should start with understanding where we currently are. METHODS: Prior to the events of 2020, in the spring of 2018, we conducted nine key informant interviews to learn about the challenges and best practices from schools deemed to be positive deviants in teaching about structural racism. FINDINGS: Our interviews showed that even those schools deemed positive deviants in the amount of teaching done about structural racism faced significant barriers in providing a robust education. CONCLUSIONS: Significant structural change, perhaps far beyond what most schools consider themselves willing and able to engage in, will be necessary if future US physicians are to fully understand and address structural racism as it affects their profession, their practice, and their patients.


Asunto(s)
COVID-19 , Educación Médica , Humanos , Facultades de Medicina , Racismo Sistemático , COVID-19/epidemiología , Curriculum
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