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1.
N Engl J Med ; 390(16): 1493-1504, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38657245

RESUMEN

BACKGROUND: Most moderate-to-late-preterm infants need nutritional support until they are feeding exclusively on their mother's breast milk. Evidence to guide nutrition strategies for these infants is lacking. METHODS: We conducted a multicenter, factorial, randomized trial involving infants born at 32 weeks 0 days' to 35 weeks 6 days' gestation who had intravenous access and whose mothers intended to breast-feed. Each infant was assigned to three interventions or their comparators: intravenous amino acid solution (parenteral nutrition) or dextrose solution until full feeding with milk was established; milk supplement given when maternal milk was insufficient or mother's breast milk exclusively with no supplementation; and taste and smell exposure before gastric-tube feeding or no taste and smell exposure. The primary outcome for the parenteral nutrition and the milk supplement interventions was the body-fat percentage at 4 months of corrected gestational age, and the primary outcome for the taste and smell intervention was the time to full enteral feeding (150 ml per kilogram of body weight per day or exclusive breast-feeding). RESULTS: A total of 532 infants (291 boys [55%]) were included in the trial. The mean (±SD) body-fat percentage at 4 months was similar among the infants who received parenteral nutrition and those who received dextrose solution (26.0±5.4% vs. 26.2±5.2%; adjusted mean difference, -0.20; 95% confidence interval [CI], -1.32 to 0.92; P = 0.72) and among the infants who received milk supplement and those who received mother's breast milk exclusively (26.3±5.3% vs. 25.8±5.4%; adjusted mean difference, 0.65; 95% CI, -0.45 to 1.74; P = 0.25). The time to full enteral feeding was similar among the infants who were exposed to taste and smell and those who were not (5.8±1.5 vs. 5.7±1.9 days; P = 0.59). Secondary outcomes were similar across interventions. Serious adverse events occurred in one infant. CONCLUSIONS: This trial of routine nutrition interventions to support moderate-to-late-preterm infants until full nutrition with mother's breast milk was possible did not show any effects on the time to full enteral feeding or on body composition at 4 months of corrected gestational age. (Funded by the Health Research Council of New Zealand and others; DIAMOND Australian New Zealand Clinical Trials Registry number, ACTRN12616001199404.).


Asunto(s)
Lactancia Materna , Nutrición Enteral , Recien Nacido Prematuro , Nutrición Parenteral , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Aminoácidos/administración & dosificación , Edad Gestacional , Glucosa/administración & dosificación , Leche Humana , Olfato , Gusto , Apoyo Nutricional , Soluciones para Nutrición Parenteral/uso terapéutico , Adiposidad
2.
J Synchrotron Radiat ; 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39078692

RESUMEN

A 1D imaging soft X-ray spectrometer installed on the small quantum systems (SQS) scientific instrument of the European XFEL is described. It uses movable cylindrical constant-line-spacing gratings in the Rowland configuration for energy dispersion in the vertical plane, and Wolter optics for simultaneous 1D imaging of the source in the horizontal plane. The soft X-ray fluorescence spectro-imaging capability will be exploited in pump-probe measurements and in investigations of propagation effects and other nonlinear phenomena.

3.
Voluntas ; 35(2): 386-396, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38665299

RESUMEN

We investigate how nonprofit organizations (NPOs) construct imaginaries of their premises, their local environment, and beyond. Based on a qualitative analysis of the websites of 209 randomly sampled NPOs in a metropolitan region in Central Europe, we find four distinct spatial imaginaries: (1) The world polity imaginary constructs NPOs as a part of a spatial environment that is neatly divided into nation states, supranational structures, and subnational units. (2) In the world society imaginary, NPOs are active in blurred, fluid, and overlapping spaces such as networks, commercialized spaces, or natural habitats. (3) In a religious imaginary, the material world is complemented by a transcendental realm and categorized into spaces of the sacred and the evil. (4) Finally, in a lococentric imaginary, NPOs construct a dichotomy between "home" and the alien rest of the world. Each of these spatial imaginaries conveys distinctive ways of situating the organization in their spatial environment and implies specific organizational practices and emotional enchantments of space. Supplementary Information: The online version contains supplementary material available at 10.1007/s11266-023-00603-w.

4.
Phys Rev Lett ; 131(25): 253201, 2023 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-38181353

RESUMEN

Excited double-core-hole states of isolated water molecules resulting from the sequential absorption of two x-ray photons have been investigated. These states are formed through an alternative pathway, where the initial step of core ionization is accompanied by the shake-up of a valence electron, leading to the same final states as in the core-ionization followed by core-excitation pathway. The capability of the x-ray free-electron laser to deliver very intense, very short, and tunable light pulses is fully exploited to identify the two different pathways.

5.
Children (Basel) ; 11(3)2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38539380

RESUMEN

Deferred cord clamping (DCC) has been associated with reduced mortality in preterm infants, and a period of at least 30 s has been recommended before clamping. However, preterm infants assessed as being in need of resuscitation have often had earlier cord clamping. In this study, we aimed to compare neonatal outcomes for preterm infants undergoing DCC who established early breathing movements compared to those who were not breathing. After a 5 yr recruitment period, we recently completed the ABC study, in which preterm infants <31 weeks undergoing 50 s of DCC who were not breathing by 15 s of age were randomised into two groups: one received intermittent positive pressure ventilation (IPPV) and the other was a standard group, which received no breathing support. The outcomes in the two groups were similar, and for the present analysis, the groups were combined. Infants in the ABC study were compared with the cohort excluded from the original ABC study because they were breathing by 15 s (called the Breathing Before Clamping or BBC group). There were significant differences in demographics between the ABC and BBC groups. Spontaneous preterm labour was more common in the BBC group, and these infants were more likely to be delivered vaginally. Gestational age and birth weight were significantly higher in the BBC group (p < 0.01). Soon after birth, Apgar scores were significantly higher in the BBC group, with a lower base deficit on first obtained blood gas, and a smaller proportion were intubated in the delivery room. Fewer BBC infants were hypothermic (<36.5 °C) on admission. Multivariate regression analysis indicated whether infants were breathing or not at 15 s of age was linked predominantly to gestation. Important neonatal outcomes and a composite of these outcomes (mortality, severe intraventricular haemorrhage, bronchopulmonary dysplasia) were not significantly different between the ABC and BBC groups (odds ratio for the composite outcome was 1.77 CI 0.84-3.76 corrected for gestation). For very preterm infants undergoing DCC, important neonatal outcomes were related to gestational age and not independently associated with early breathing. There was a small group (7% of total) who were deemed compromised at birth and did not undergo DCC. These infants had significantly worse neonatal outcomes.

6.
J Cardiovasc Med (Hagerstown) ; 25(1): 68-75, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-38079283

RESUMEN

AIMS: Central SBP (cSBP) was shown to be increased already in children with congenital heart disease (CHD). However, its development over time has not yet been investigated. The aim of this study was to evaluate the natural course of cSBP over time from longitudinal assessment in children with CHD. METHODS: In this longitudinal study, 306 children and adolescents (11.3 ±â€Š2.9 years, 34% girls) with various CHD were prospectively examined from July 2014 to May 2022. Over a mean follow-up length of 30.1 ±â€Š18.9 months, 467 follow-up assessments have been conducted. cSBP was noninvasively assessed by oscillometric measurement via Mobil-O-Graph. A linear mixed effect model was performed to examine the course of cSBP. RESULTS: cSBP increased significantly over time by 1.22 mmHg per year of age (P < 0.001). The longitudinal increase in cSBP over time remained significant when including sex (b = 0.68, P < 0.001), BMI (b = 1.12, P < 0.001), hypertensive medication (b = 1.13, P < 0.001), disease severity (b = 1.04, P < 0.001), and CHD type (b = 3.74, P = 0.03) in the model. Patients with transposition of the great arteries (TGA) after arterial switch had a significantly higher cSBP increase over time (b = 1.78, P < 0.001). The longitudinal cSBP increase was significantly higher in obese CHD children (b = 2.52, P = 0.005) and in boys (b = 0.85, P < 0.001). CONCLUSION: This study shows a longitudinal increase in cSBP in children with CHD. Whether observed trajectories of cSBP are normal or abnormal needs to be investigated in further studies. Monitoring of the vascular function with a special focus on patients with TGA and obese CHD children seems indicated.


Asunto(s)
Transposición de los Grandes Vasos , Masculino , Femenino , Adolescente , Niño , Humanos , Presión Sanguínea , Estudios Longitudinales , Obesidad
7.
J Pers Med ; 14(5)2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38793033

RESUMEN

Polymyalgia rheumatica (PMR) is an inflammatory disorder of unknown etiology, sharing symptoms with giant cell arthritis (GCA) and rheumatoid arthritis (RA). The pathogenic inflammatory roots are still not well understood, and there is a lack of extensive biomarker studies to explain the disease debut and post-acute phase. This study aimed to deeply analyze the serum proteome and inflammatory response of PMR patients before and after glucocorticoid treatment. We included treatment-naïve PMR patients, collecting samples before and after 3 months of treatment. For comparison, disease-modifying antirheumatic drug (DMARD)-naïve RA patients were included and matched to healthy controls (CTL). The serum proteome was examined using label-free quantitative mass spectrometry, while inflammation levels were assessed using multiplex inflammatory cytokine and cell-free DNA assays. The serum proteomes of the four groups comprised acute phase reactants, coagulation factors, complement proteins, immunoglobulins, and apolipoproteins. Serum amyloid A (SAA1) was significantly reduced by active PMR treatment. Cell-free DNA levels in PMR and RA groups were significantly higher than in healthy controls due to acute inflammation. Complement factors had minimal changes post-treatment. The individual serum proteome in PMR patients showed over 100 abundantly variable proteins, emphasizing the systemic impact of PMR disease debut and the effect of treatment. Interleukin (IL)-6 and interferon-gamma (IFN-γ) were significantly impacted by glucocorticoid treatment. Our study defines the PMR serum proteome during glucocorticoid treatment and highlights the role of SAA1, IL-6, and IFN-γ in treatment responses. An involvement of PGLYRP2 in acute PMR could indicate a response to bacterial infection, highlighting its role in the acute phase of the immune response. The results suggest that PMR may be an aberrant response to a bacterial infection with an exacerbated IL-6 and acute phase inflammatory response and molecular attempts to limit the inflammation.

8.
JAMA Netw Open ; 7(6): e2415764, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38869900

RESUMEN

Importance: Neonatal hypoglycemia is an important preventable cause of neurodevelopmental impairment, but there is a paucity of evidence to guide treatment. Objective: To evaluate whether early, low-dose oral diazoxide for severe or recurrent neonatal hypoglycemia reduces time to resolution of hypoglycemia. Design, Setting, and Participants: This 2-arm, placebo-controlled randomized clinical trial was conducted from May 2020 to February 2023 in tertiary neonatal units at 2 New Zealand hospitals. Participants were neonates born at 35 or more weeks' gestation and less than 1 week of age with severe hypoglycemia (blood glucose concentration <22 mg/dL or <36 mg/dL despite 2 doses of dextrose gel) or recurrent hypoglycemia (≥3 episodes of a blood glucose concentration <47 mg/dL within 48 hours). Interventions: Newborns were randomized 1:1 to receive diazoxide suspension (loading dose, 5 mg/kg; maintenance, 1.5 mg/kg every 12 hours) or placebo, titrated per protocol. Main Outcome and Measures: The primary outcome was time to resolution of hypoglycemia, defined as enteral bolus feeding without intravenous fluids and normoglycemia (blood glucose concentration of 47-98 mg/dL) for at least 24 hours, compared between groups using adjusted Cox proportional hazards regression. Hazard ratios adjusted for stratification variables and gestation length are reported. Prespecified secondary outcomes, including number of blood glucose tests and episodes of hypoglycemia, duration of hypoglycemia, and time to enteral bolus feeding and weaning from intravenous fluids, were compared by generalized linear models. Newborns were followed up for at least 2 weeks. Results: Of 154 newborns screened, 75 were randomized and 74 with evaluable data were included in the analysis (mean [SD] gestational age for the full cohort, 37.6 [1.6] weeks), 36 in the diazoxide group and 38 in the placebo group. Baseline characteristics were similar: in the diazoxide group, mean (SD) gestational age was 37.9 (1.6) weeks and 26 (72%) were male; in the placebo group, mean (SD) gestational age was 37.4 (1.5) weeks and 27 (71%) were male. There was no significant difference in time to resolution of hypoglycemia (adjusted hazard ratio [AHR], 1.39; 95% CI, 0.84-2.23), possibly due to increased episodes of elevated blood glucose concentration and longer time to normoglycemia in the diazoxide group. Resolution of hypoglycemia, when redefined post hoc as enteral bolus feeding without intravenous fluids for at least 24 hours with no further hypoglycemia, was reached by more newborns in the diazoxide group (AHR, 2.60; 95% CI, 1.53-4.46). Newborns in the diazoxide group had fewer blood glucose tests (adjusted count ratio [ACR], 0.63; 95% CI, 0.56-0.71) and episodes of hypoglycemia (ACR, 0.32; 95% CI, 0.17-0.63), reduced duration of hypoglycemia (adjusted ratio of geometric means [ARGM], 0.18; 95% CI, 0.06-0.53), and reduced time to enteral bolus feeding (ARGM, 0.74; 95% CI, 0.58-0.95) and weaning from intravenous fluids (ARGM, 0.72; 95% CI, 0.60-0.87). Only 2 newborns (6%) treated with diazoxide had hypoglycemia after the loading dose compared with 20 (53%) with placebo. Conclusions and Relevance: In this randomized clinical trial, early treatment of severe or recurrent neonatal hypoglycemia with low-dose oral diazoxide did not reduce time to resolution of hypoglycemia but reduced time to enteral bolus feeding and weaning from intravenous fluids, duration of hypoglycemia, and frequency of blood glucose testing compared with placebo. Trial Registration: ANZCTR.org.au Identifier: ACTRN12620000129987.


Asunto(s)
Diazóxido , Hipoglucemia , Humanos , Diazóxido/uso terapéutico , Diazóxido/administración & dosificación , Recién Nacido , Femenino , Masculino , Nueva Zelanda , Recurrencia , Glucemia/efectos de los fármacos , Glucemia/análisis , Resultado del Tratamiento
9.
Sci Adv ; 10(16): eado0668, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38630815

RESUMEN

Quantum entanglement between the degrees of freedom encountered in the classical world is challenging to observe due to the surrounding environment. To elucidate this issue, we investigate the entanglement generated over ultrafast timescales in a bipartite quantum system comprising two massive particles: a free-moving photoelectron, which expands to a mesoscopic length scale, and a light-dressed atomic ion, which represents a hybrid state of light and matter. Although the photoelectron spectra are measured classically, the entanglement allows us to reveal information about the dressed-state dynamics of the ion and the femtosecond extreme ultraviolet pulses delivered by a seeded free-electron laser. The observed generation of entanglement is interpreted using the time-dependent von Neumann entropy. Our results unveil the potential for using short-wavelength coherent light pulses from free-electron lasers to generate entangled photoelectron and ion systems for studying spooky action at a distance.

10.
Sci Data ; 11(1): 77, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38228637

RESUMEN

Lake trophic state is a key ecosystem property that integrates a lake's physical, chemical, and biological processes. Despite the importance of trophic state as a gauge of lake water quality, standardized and machine-readable observations are uncommon. Remote sensing presents an opportunity to detect and analyze lake trophic state with reproducible, robust methods across time and space. We used Landsat surface reflectance data to create the first compendium of annual lake trophic state for 55,662 lakes of at least 10 ha in area throughout the contiguous United States from 1984 through 2020. The dataset was constructed with FAIR data principles (Findable, Accessible, Interoperable, and Reproducible) in mind, where data are publicly available, relational keys from parent datasets are retained, and all data wrangling and modeling routines are scripted for future reuse. Together, this resource offers critical data to address basic and applied research questions about lake water quality at a suite of spatial and temporal scales.

11.
JAMA Pediatr ; 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39158898

RESUMEN

Importance: There is a recognized unmet need for clinical trials to provide evidence-informed care for infants, children and adolescents. This Special Communication outlines the capacity of 3 distinct trial design strategies, sequential, parallel, and a unified adult-pediatric bayesian adaptive design, to incorporate children into clinical trials and transform this current state of evidence inequity. A unified adult-pediatric whole-of-life clinical trial is demonstrated through the Staphylococcus aureus Network Adaptive Platform (SNAP) trial. Observations: Bayesian methods provide a framework for synthesizing data in the form of a probability model that can be used in the design and analysis of a clinical trial. Three trial design strategies are compared: (1) a sequential adult-pediatric bayesian approach that involves a separate, deferred pediatric trial that incorporates existing adult trial data into the analysis model to potentially reduce the pediatric trial sample size; (2) a parallel adult-pediatric bayesian trial whereby separate pediatric enrollment occurs in a parallel trial, running alongside an adult randomized clinical trial; and (3) a unified adult-pediatric bayesian adaptive design that supports the enrollment of both children and adults simultaneously in a whole-of-life bayesian adaptive randomized clinical trial. The SNAP trial whole-of-life design uses a bayesian hierarchical model that allows information sharing (also known as borrowing) between trial age groups by linking intervention effects of children and adults, thereby improving inference in both groups. Conclusion and Relevance: Bayesian hierarchical models may provide more precision for estimates of safety and efficacy of treatments in trials with heterogenous populations compared to traditional methods of analysis. They facilitate the inclusion of children in clinical trials and a shift from children deemed therapeutic orphans to the vision of no child left behind in clinical trials to ensure evidence for clinical practice exists across the life course. The SNAP trial provides an example of a bayesian adaptive whole-of-life inclusion design that enhances trial population inclusivity and diversity overall, as well as generalizability and translation of findings into clinical practice.

12.
Light Sci Appl ; 13(1): 15, 2024 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-38216563

RESUMEN

The idea of using ultrashort X-ray pulses to obtain images of single proteins frozen in time has fascinated and inspired many. It was one of the arguments for building X-ray free-electron lasers. According to theory, the extremely intense pulses provide sufficient signal to dispense with using crystals as an amplifier, and the ultrashort pulse duration permits capturing the diffraction data before the sample inevitably explodes. This was first demonstrated on biological samples a decade ago on the giant mimivirus. Since then, a large collaboration has been pushing the limit of the smallest sample that can be imaged. The ability to capture snapshots on the timescale of atomic vibrations, while keeping the sample at room temperature, may allow probing the entire conformational phase space of macromolecules. Here we show the first observation of an X-ray diffraction pattern from a single protein, that of Escherichia coli GroEL which at 14 nm in diameter is the smallest biological sample ever imaged by X-rays, and demonstrate that the concept of diffraction before destruction extends to single proteins. From the pattern, it is possible to determine the approximate orientation of the protein. Our experiment demonstrates the feasibility of ultrafast imaging of single proteins, opening the way to single-molecule time-resolved studies on the femtosecond timescale.

14.
Braz. arch. biol. technol ; 58(1): 109-117, Jan-Feb/2015. tab, graf
Artículo en Inglés | LILACS | ID: lil-735825

RESUMEN

This study showed that thermally labile fibrillar collagen could be processed continuously in combination with gelatine as foaming additive by convection drying. The procedure led to stable sponges with similar structural and physical properties as found for freeze-dried collagen samples. The fibrillar collagen remained native, while gelatine acted as foaming additive. The absorbency of the sponges was improved by opening the surface with abrasives. A use as medical device with hemostyptic properties would be possible.

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