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1.
J Plast Surg Hand Surg ; 59: 40-45, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566324

RESUMO

AIM: The purpose of this study was to evaluate clinical, patient rated and radiological outcome of the scaphoid trapezium pyrocarbon implant (STPI) at a minimum of three years follow-up. METHODS: Consecutive patients operated with the STPI due to scaphotrapeziotrapezoidal (STT) arthritis between 2012 and 2019 were included. Patients were evaluated preoperatively and annually after surgery for range of motion, grip strength, key pinch, quick-DASH, pain, and satisfaction. Radiographs were evaluated for implant position, signs of dorsal intercalated segment instability (DISI), capitolunate (CL) angle, scapholunate (SL) distance, and presence of osteophytes. RESULTS: Twenty-six patients (29 implants) were included. Seven implants were revised during the follow up, mainly due to pain: three implants were removed, four patients received a new STPI of a different size, leaving 22 implants in 20 patients available for follow up, 9 males and 11 females. Median age was 61.7 years (51-78 years). Median follow-up time was 68 months (37-105 months). Comparing preoperative status to the last follow-up, wrist extension and deviation, thumb abduction, and grip strength did not change. Key Pinch, quick DASH, pain, and patient satisfaction improved significantly at last follow-up. Radiographic signs of DISI were seen in six cases preoperatively and in 12 cases at last follow-up. CONLUSION: At a minimum of three years follow-up, the STPI used for STT-arthritis improve pain, quick-DASH result, and patient satisfaction significantly. ROM and grip strength did not change compared to preoperative values. Radiographic signs of carpal instability were common at the follow-up and the revision rate was high.


Assuntos
Artrite , Carbono , Osso Escafoide , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Seguimentos , Estudos Retrospectivos , Osso Escafoide/diagnóstico por imagem , Osso Escafoide/cirurgia , Dor , Amplitude de Movimento Articular , Força da Mão
2.
J Gambl Stud ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38592615

RESUMO

Problem gambling (PG) is a public health concern with severe repercussions for the individual, concerned significant others and the society. Foreign borns generally gamble less but are overrepresented among those with PG. Previous research has suggested that other factors, such as socio-economic status, might explain this, but also that cultural factors might play a role in the relationship to gambling and the development of PG. This qualitative study using content analysis investigates the experiences of and opinions about gambling and PG among 12 males living in Sweden with a migrant background in Afghanistan, the Middle East and North Africa. The results were show that the acculturation process could be a factor in developing PG, as well as a cultural values regarding money and wealth. PG was seen as more stigmatized in the origin country, and the family played a more important role in the rehabilitation of PG compared to the general population. The results of this study could be used to inform preventive and clinical programs to better reach people with a migrant background.

3.
Clin Nutr ; 43(5): 1162-1170, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38603973

RESUMO

BACKGROUND & AIM: Clinical trials supplementing the long-chain polyunsaturated fatty acids (LCPUFAs) docosahexaenoic acid (DHA) and arachidonic acid (AA) to preterm infants have shown positive effects on inflammation-related morbidities, but the molecular mechanisms underlying these effects are not fully elucidated. This study aimed to determine associations between DHA, AA, and inflammation-related proteins during the neonatal period in extremely preterm infants. METHODS: A retrospective exploratory study of infants (n = 183) born below 28 weeks gestation from the Mega Donna Mega trial, a randomized multicenter trial designed to study the effect of DHA and AA on retinopathy of prematurity. Serial serum samples were collected after birth until postnatal day 100 (median 7 samples per infant) and analyzed for phospholipid fatty acids and proteins using targeted proteomics covering 538 proteins. Associations over time between LCPUFAs and proteins were explored using mixed effect modeling with splines, including an interaction term for time, and adjusted for gestational age, sex, and center. RESULTS: On postnatal day one, 55 proteins correlated with DHA levels and 10 proteins with AA levels. Five proteins were related to both fatty acids, all with a positive correlation. Over the first 100 days after birth, we identified 57 proteins to be associated with DHA and/or AA. Of these proteins, 41 (72%) related to inflammation. Thirty-eight proteins were associated with both fatty acids and the overall direction of association did not differ between DHA and AA, indicating that both LCPUFAs similarly contribute to up- and down-regulation of the preterm neonate inflammatory proteome. Primary examples of this were the inflammation-modulating cytokines IL-6 and CCL7, both being negatively related to levels of DHA and AA in the postnatal period. CONCLUSIONS: This study supports postnatal non-antagonistic and potentially synergistic effects of DHA and AA on the inflammation proteome in preterm infants, indicating that supplementation with both fatty acids may contribute to limiting the disease burden in this vulnerable population. CLINICAL REGISTRATION NUMBER: ClinicalTrials.gov (NCT03201588).

4.
Prostaglandins Leukot Essent Fatty Acids ; 201: 102613, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38377640

RESUMO

Enteral supplementation with arachidonic acid (AA) and docosahexaenoic acid (DHA) in extremely preterm infants has shown beneficial effects on retinopathy of prematurity and pulmonary outcome whereas exclusive DHA supplementation has been associated with increased pulmonary morbidity. This secondary analysis evaluates pulmonary outcome in 204 extremely preterm infants, randomized to receive AA (100 mg/kg/day) and DHA (50 mg/kg/day) enterally from birth until term age or standard care. Pulmonary morbidity was primarily assessed based on severity of bronchopulmonary dysplasia (BPD). Serum levels of AA and DHA during the first 28 days were analysed in relation to BPD. Supplementation with AA:DHA was not associated with increased BPD severity, adjusted OR 1.48 (95 % CI 0.85-2.61), nor with increased need for respiratory support at post menstrual age 36 weeks or duration of oxygen supplementation. Every 1 % increase in AA was associated with a reduction of BPD severity, adjusted OR 0.73 (95 % CI 0.58-0.92). In conclusion, in this study, with limited statistical power, enteral supplementation with AA:DHA was not associated with an increased risk of pulmonary morbidity, but higher levels of AA were associated with less severe BPD. Whether AA or the combination of AA and DHA have beneficial roles in the immature lung needs further research.

5.
Nature ; 625(7994): 282-286, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38200297

RESUMO

The large-scale conversion of N2 and H2 into NH3 (refs. 1,2) over Fe and Ru catalysts3 for fertilizer production occurs through the Haber-Bosch process, which has been considered the most important scientific invention of the twentieth century4. The active component of the catalyst enabling the conversion was variously considered to be the oxide5, nitride2, metallic phase or surface nitride6, and the rate-limiting step has been associated with N2 dissociation7-9, reaction of the adsorbed nitrogen10 and also NH3 desorption11. This range of views reflects that the Haber-Bosch process operates at high temperatures and pressures, whereas surface-sensitive techniques that might differentiate between different mechanistic proposals require vacuum conditions. Mechanistic studies have accordingly long been limited to theoretical calculations12. Here we use X-ray photoelectron spectroscopy-capable of revealing the chemical state of catalytic surfaces and recently adapted to operando investigations13 of methanol14 and Fischer-Tropsch synthesis15-to determine the surface composition of Fe and Ru catalysts during NH3 production at pressures up to 1 bar and temperatures as high as 723 K. We find that, although flat and stepped Fe surfaces and Ru single-crystal surfaces all remain metallic, the latter are almost adsorbate free, whereas Fe catalysts retain a small amount of adsorbed N and develop at lower temperatures high amine (NHx) coverages on the stepped surfaces. These observations indicate that the rate-limiting step on Ru is always N2 dissociation. On Fe catalysts, by contrast and as predicted by theory16, hydrogenation of adsorbed N atoms is less efficient to the extent that the rate-limiting step switches following temperature lowering from N2 dissociation to the hydrogenation of surface species.

6.
Chemphyschem ; 25(1): e202300523, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37877432

RESUMO

Operando probing by x-ray photoelectron spectroscopy (XPS) of certain hydrogenation reactions are often limited by the scattering of photoelectrons in the gas phase. This work describes a method designed to partially circumvent this so called pressure gap. By performing a rapid switch from a high pressure (where acquisition is impossible) to a lower pressure we can for a short while probe a "remnant" of the high pressure surface as well as the time dynamics during the re-equilibration to the new pressure. This methodology is demonstrated using the CO2 and the CO hydrogenation reaction over Rh(211). In the CO2 hydrogenation reaction, the remnant surface of a 2 bar pressure shows an adsorbate distribution which favors chemisorbed CHx adsorbates over chemisorbed CO. This contrasts against previous static operando spectra acquired at lower pressures. Furthermore, the pressure jumping method yields a faster acquisition and more detailed spectra than static operando measurements above 1 bar. In the CO hydrogenation reaction, we observe that CHx accumulated faster during the 275 mbar low pressure regime, and different hypotheses are presented regarding this observation.

7.
JCPP Adv ; 3(4): e12179, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38054048

RESUMO

Background: Gaming is a popular past-time activity among children and adolescents, but it there is also a possible link to negative consequences such as psychological distress and lowered academic achievement. However, there are fundamental knowledge gaps remaining regarding central characteristics of gaming such as heritability, stability over time, and sex differences. We examined the genetic and environmental contribution to gaming behavior, including sex differences, continuity and change, in a longitudinal cohort of twins. Methods: This is the first longitudinal twin study on gaming, involving 32,006 twins in Sweden. Parents were asked about the twins' gaming at ages 9, 15 and 18. We used univariate and multivariate twin analyses to estimate the relative contribution of genetic and environmental influences at each time-point as well as across time. Sex-differences were also explored. Results: The results showed large sex differences, where genetics explained more of the variance for boys (31.3%-62.5% depending on age) than for girls (19.4%-23.4%). Genetic factors explained an increasing amount of the variance for boys (31.3% at age 9, 62.5% at age 15 and 53.9% at age 18). Shared environmental factors explained a larger proportion of the variance among girls, which remained relatively stable over time (70.5% at age 9, 61.8% at age 15 and 60.5% at age 18). The results also indicated that most of the variance came from genetic and environmental sources specific to each age. Conclusions: Compared to many other behavioral phenotypes, such as gambling, gaming was relatively unstable with a large degree of genetic innovation. There were large sex differences in the contribution of genetic and environmental factors. This suggests that excessive gaming could be the result of age- and sex-specific genetic and environmental factors, and should be taken into account when mapping gaming behaviors, since these behaviors might be under continual etiological transformation.

8.
Sci Rep ; 13(1): 19476, 2023 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-37945638

RESUMO

Numerous in vivo studies on the ketogenic diet, a diet that can induce metabolic conditions resembling those following extended starvation, demonstrate strong outcomes on cancer survival, particularly when combined with chemo-, radio- or immunological treatments. However, the therapeutic application of ketogenic diets requires strict dietary adherence from well-informed and motivated patients, and it has recently been proposed that hemodialysis might be utilized to boost ketosis and further destabilize the environment for cancer cells. Yet, plasma ketones may be lost in the dialysate-lowering blood ketone levels. Here we performed a single 180-min experimental hemodialysis (HD) session in six anesthetized Sprague-Dawley rats given ketogenic diet for five days. Median blood ketone levels pre-dialysis were 3.5 mmol/L (IQR 2.2 to 5.6) and 3.8 mmol/L (IQR 2.2 to 5.1) after 180 min HD, p = 0.54 (95% CI - 0.6 to 1.2). Plasma glucose levels were reduced by 36% (- 4.5 mmol/L), p < 0.05 (95% CI - 6.7 to - 2.5). Standard base excess was increased from - 3.5 mmol/L (IQR - 4 to - 2) to 0.5 mmol/L (IQR - 1 to 3), p < 0.01 (95% CI 2.0 to 5.0). A theoretical model was applied confirming that intra-dialytic glucose levels decrease, and ketone levels slightly increase since hepatic ketone production far exceeds dialytic removal. Our experimental data and in-silico modeling indicate that elevated blood ketone levels during ketosis are maintained during hemodialysis despite dialytic removal.


Assuntos
Dieta Cetogênica , Cetose , Neoplasias , Humanos , Ratos , Animais , Diálise , Ratos Sprague-Dawley , Dieta , Cetonas/efeitos adversos , Diálise Renal , Adjuvantes Imunológicos/efeitos adversos , Neoplasias/terapia
9.
iScience ; 26(10): 108021, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37841591

RESUMO

Nutritional deprivation occurring in most preterm infants postnatally can induce hyperglycemia, a significant and independent risk factor for suppressing physiological retinal vascularization (Phase I retinopathy of prematurity (ROP)), leading to compensatory but pathological neovascularization. Amino acid supplementation reduces retinal neovascularization in mice. Little is known about amino acid contribution to Phase I ROP. In mice modeling hyperglycemia-associated Phase I ROP, we found significant changes in retinal amino acids (including most decreased L-leucine, L-isoleucine, and L-valine). Parenteral L-isoleucine suppressed physiological retinal vascularization. In premature infants, severe ROP was associated with a higher mean intake of parenteral versus enteral amino acids in the first two weeks of life after adjustment for treatment group, gestational age at birth, birth weight, and sex. The number of days with parenteral amino acids support independently predicted severe ROP. Further understanding and modulating amino acids may help improve nutritional intervention and prevent Phase I ROP.

10.
Lancet Reg Health Eur ; 32: 100696, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37671123

RESUMO

Background: We investigated ophthalmological outcomes at 2.5 years of corrected age in children born extremely preterm (EPT) to evaluate the effects of postnatal enteral supplementation with ω-3 and ω-6 long-chain polyunsaturated fatty acids. Methods: In the Mega Donna Mega clinical trial, EPT infants born at less than 28 weeks of gestation were randomized to receive an enteral supplementation of docosahexaenoic acid (DHA) and arachidonic acid (AA) from birth to 40 weeks postmenstrual age. In this exploratory follow-up at 2.5 years of corrected age, we assessed visual acuity (VA), refraction, manifest strabismus, and nystagmus. Satisfactory VA was defined as ≥20/63. Multiple imputation (MI) was used to address the issue of missing data. Findings: Of 178 children in the trial, 115 (with median gestational age (GA) of 25 + 4/7 weeks and median birth weights of 790 g) were ophthalmologically assessed at a median corrected age of 2.7 years (range 2.0-3.9 years). VA assessment was missing in 42.1% (75/178), in 41.7% (35/84) of the AA/DHA supplemented infants, and in 42.6% (40/94) of the control infants. After MI and adjustments for GA, study center, plurality, and corrected age at VA exam, no significant effect of AA/DHA supplementation was detected in VA outcome (≥20/63) (odds ratio 2.16, confidence interval 95% 0.99-4.69, p = 0.053). Interpretation: In this randomized controlled trial follow-up, postnatal supplementation with enteral AA/DHA to EPT children did not significantly alter VA at 2.5 years of corrected age. Due to the high loss to follow-up rate and the limited statistical power, additional studies are needed. Funding: The Swedish Medical Research Council #2020-01092, The Gothenburg Medical Society, Government grants under the ALF agreement ALFGBG-717971 and ALFGBG-971188, De Blindas Vänner, Knut and Alice Wallenberg Foundation - Wallenberg Clinical Scholars, NIHEY017017, EY030904BCHIDDRC (1U54HD090255 Massachusetts Lions Eye Foundation) supported the study.

11.
Eur J Surg Oncol ; 49(11): 107046, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37716017

RESUMO

INTRODUCTION: A nationwide multicenter study was performed to examine short- and long-term effects of irreversible electroporation (IRE) for hepatocellular carcinoma (HCC) and colorectal cancer liver metastases (CRCLM). IRE is an alternative method when thermal ablation is contraindicated because of risk for serious thermal complications. METHODS: All consecutive patients in Sweden treated with IRE because of HCC or CRCLM, were included between 2011 and 2018. We evaluated medical records and radiological imaging to obtain information regarding patient-, tumor-, and treatment characteristics. We also assessed local tumor progression, and survival. RESULTS: In total 206 tumors in 149 patients were treated with IRE. Eighty-seven patients (58.4%) had colorectal cancer liver metastases, and 62 patients (41.6%) had hepatocellular carcinoma. Median tumor size was 20 mm (i.q.r. 14-26 mm). Median overall survival for CRCLM and HCC, were 27.0 months (95% CI 22.2-31.8 months), and 35.0 months (95% CI 13.8-56.2 months), respectively. Median follow-up time was 58 months (95% CI 50.6-65.4). Local ablation success at six and twelve months for HCC was 58.3% and 40.3%, and for CRCLM 37.7% and 25.4%. The median time to local tumor progression (LTP) for HCC was 21.0 months (95% CI: 9.5-32.5 months), and for CRCLM 6.0 months (95% CI: 4.5-7.5 months). At 30-day follow-up, 15.4% (n = 23) of patients suffered from a complication rated as Clavien-Dindo grade 1-3a. Three patients (2.0%) had grade 3b-5 with one death in a thromboembolic event. CONCLUSION: IRE is a safe ablation modality for patients with liver tumors that are located in such a way that other treatment options are unsuitable.


Assuntos
Carcinoma Hepatocelular , Neoplasias Colorretais , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/secundário , Seguimentos , Eletroporação/métodos , Neoplasias Colorretais/patologia , Resultado do Tratamento
12.
Commun Med (Lond) ; 3(1): 107, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37532738

RESUMO

BACKGROUND: Preterm birth is the leading cause of neonatal mortality and morbidity. Early diagnosis and interventions are critical to improving the clinical outcomes of extremely premature infants. Blood protein profiling during the first months of life in preterm infants can shed light on the role of early extrauterine development and provide an increased understanding of maturation after extremely preterm birth and the underlying mechanisms of prematurity-related disorders. METHODS: We have investigated the blood protein profiles during the first months of life in preterm infants on the role of early extrauterine development. The blood protein levels were analyzed using next generation blood profiling on 1335 serum samples, collected longitudinally at nine time points from birth to full-term from 182 extremely preterm infants. RESULTS: The protein analysis reveals evident predestined serum evolution patterns common for all included infants. The majority of the variations in blood protein expression are associated with the postnatal age of the preterm infants rather than any other factors. There is a uniform protein pattern on postnatal day 1 and after 30 weeks postmenstrual age (PMA), independent of gestational age (GA). However, during the first month of life, GA had a significant impact on protein variability. CONCLUSIONS: The unified pattern of protein development for all included infants suggests an age-dependent stereotypic development of blood proteins after birth. This knowledge should be considered in neonatal settings and might alter the clinical approach within neonatology, where PMA is today the most dominant age variable.


Being born too early can affect a baby's health. We looked at how babies born extremely preterm, meaning more than 12 weeks earlier than a full-term baby, develop. We looked at the proteins present in their blood from the day they were born until their original due date. Our study of 182 extremely preterm babies born at different points in the pregnancy (gestational ages) found that the proteins present in their blood changed in a similar way over time. This means that the age of a baby after birth, and not how early they were born, mostly affects the proteins in their blood. These findings help us understand how extremely preterm babies develop after birth, which could lead to improvements to their healthcare during the first few weeks of their life.

13.
iScience ; 26(7): 107217, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37496672

RESUMO

Staphylococcus (S.) epidermidis is the most common nosocomial coagulase-negative staphylococci infection in preterm infants. Clinical signs of infection are often unspecific and novel markers to complement diagnosis are needed. We investigated proteomic alterations in mouse brain after S. epidermidis infection and in preterm infant blood. We identified lipocalin-2 (LCN2) as a crucial protein associated with cerebrovascular changes and astrocyte reactivity in mice. We further proved that LCN2 protein expression was associated with endothelial cells but not astrocyte reactivity. By combining network analysis and differential expression approaches, we identified LCN2 linked to blood C-reactive protein levels in preterm infants born <28 weeks of gestation. Blood LCN2 levels were associated with similar alterations of cytokines and chemokines in both infected mice and human preterm infants with increased levels of C-reactive protein. This experimental and clinical study suggests that LCN2 may be a marker of preterm infection/inflammation associated with cerebrovascular changes and neuroinflammation.

14.
Nat Commun ; 14(1): 3313, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37316494

RESUMO

The phase transition between water and ice is ubiquitous and one of the most important phenomena in nature. Here, we performed time-resolved x-ray scattering experiments capturing the melting and recrystallization dynamics of ice. The ultrafast heating of ice I is induced by an IR laser pulse and probed with an intense x-ray pulse which provided us with direct structural information on different length scales. From the wide-angle x-ray scattering (WAXS) patterns, the molten fraction, as well as the corresponding temperature at each delay, were determined. The small-angle x-ray scattering (SAXS) patterns, together with the information extracted from the WAXS analysis, provided the time-dependent change of the size and the number of liquid domains. The results show partial melting (~13%) and superheating of ice occurring at around 20 ns. After 100 ns, the average size of the liquid domains grows from about 2.5 nm to 4.5 nm by the coalescence of approximately six adjacent domains. Subsequently, we capture the recrystallization of the liquid domains, which occurs on microsecond timescales due to the cooling by heat dissipation and results to a decrease of the average liquid domain size.

15.
Clin Nutr ; 42(6): 962-971, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37120902

RESUMO

BACKGROUND & AIM: Preterm infants risk deficits of long-chain polyunsaturated fatty acids (LCPUFAs) that may contribute to morbidities and hamper neurodevelopment. We aimed to determine longitudinal serum fatty acid profiles in preterm infants and how the profiles are affected by enteral and parenteral lipid sources. METHODS: Cohort study analyzing fatty acid data from the Mega Donna Mega study, a randomized control trial with infants born <28 weeks of gestation (n = 204) receiving standard nutrition or daily enteral lipid supplementation with arachidonic acid (AA):docosahexaenoic acid (DHA) (100:50 mg/kg/day). Infants received an intravenous lipid emulsion containing olive oil:soybean oil (4:1). Infants were followed from birth to postmenstrual age 40 weeks. Levels of 31 different fatty acids from serum phospholipids were determined by GC-MS and reported in relative (mol%) and absolute concentration (µmol l-1) units. RESULTS: Higher parenteral lipid administration resulted in lower serum proportion of AA and DHA relative to other fatty acids during the first 13 weeks of life (p < 0.001 for the 25th vs the 75th percentile). The enteral AA:DHA supplement increased the target fatty acids with little impact on other fatty acids. The absolute concentration of total phospholipid fatty acids changed rapidly in the first weeks of life, peaking at day 3, median (Q1-Q3) 4452 (3645-5466) µmol l-1, and was positively correlated to the intake of parenteral lipids. Overall, infants displayed common fatty acid trajectories over the study period. However, remarkable differences in fatty acid patterns were observed depending on whether levels were expressed in relative or absolute units. For example, the relative levels of many LCPUFAs, including DHA and AA, declined rapidly after birth while their absolute concentrations increased in the first week of life. For DHA, absolute levels were significantly higher compared to cord blood from day 1 until postnatal week 16 (p < 0.001). For AA, absolute postnatal levels were lower compared to cord blood from week 4 throughout the study period (p < 0.05). CONCLUSIONS: Our data show that parenteral lipids aggravate the postnatal loss of LCPUFAs seen in preterm infants and that serum AA available for accretion is below that in utero. Further research is needed to establish optimal postnatal fatty acid supplementation and profiles in extremely preterm infants to promote development and long-term health. CLINICAL TRIAL REGISTRY: ClinicalTrials.gov, identifier: NCT03201588.


Assuntos
Ácidos Docosa-Hexaenoicos , Ácidos Graxos , Lactente , Recém-Nascido , Humanos , Ácido Araquidônico , Estudos de Coortes , Lactente Extremamente Prematuro , Fosfolipídeos
17.
Sci Total Environ ; 875: 162604, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36878298

RESUMO

Herbicide pollution poses a worldwide threat to plants and freshwater ecosystems. However, the understanding of how organisms develop tolerance to these chemicals and the associated trade-off expenses are largely unknown. This study aims to investigate the physiological and transcriptional mechanisms underlying the acclimation of the green microalgal model species Raphidocelis subcapitata (Selenastraceae) towards the herbicide diflufenican, and the fitness costs associated with tolerance development. Algae were exposed for 12 weeks (corresponding to 100 generations) to diflufenican at the two environmental concentrations 10 and 310 ng/L. The monitoring of growth, pigment composition, and photosynthetic performance throughout the experiment revealed an initial dose-dependent stress phase (week 1) with an EC50 of 397 ng/L, followed by a time-dependent recovery phase during weeks 2 to 4. After week 4, R. subcapitata was acclimated to diflufenican exposure with a similar growth rate, content of carotenoids, and photosynthetic performance as the unexposed control algae. This acclimation state of the algae was explored in terms of tolerance acquisition, changes in the fatty acids composition, diflufenican removal rate, cell size, and changes in mRNA gene expression profile, revealing potential fitness costs associated with acclimation, such as up-regulation of genes related to cell division, structure, morphology, and reduction of cell size. Overall, this study demonstrates that R. subcapitata can quickly acclimate to environmental but toxic levels of diflufenican; however, the acclimation is associated with trade-off expenses that result in smaller cell size.


Assuntos
Clorofíceas , Herbicidas , Microalgas , Poluentes Químicos da Água , Ecossistema , Transcriptoma , Herbicidas/toxicidade , Aclimatação , Poluentes Químicos da Água/toxicidade
18.
Nat Commun ; 14(1): 442, 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36707522

RESUMO

Recent experiments continue to find evidence for a liquid-liquid phase transition (LLPT) in supercooled water, which would unify our understanding of the anomalous properties of liquid water and amorphous ice. These experiments are challenging because the proposed LLPT occurs under extreme metastable conditions where the liquid freezes to a crystal on a very short time scale. Here, we analyze models for the LLPT to show that coexistence of distinct high-density and low-density liquid phases may be observed by subjecting low-density amorphous (LDA) ice to ultrafast heating. We then describe experiments in which we heat LDA ice to near the predicted critical point of the LLPT by an ultrafast infrared laser pulse, following which we measure the structure factor using femtosecond x-ray laser pulses. Consistent with our predictions, we observe a LLPT occurring on a time scale < 100 ns and widely separated from ice formation, which begins at times >1 µs.

19.
Environ Sci Atmos ; 2(6): 1314-1323, 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36561555

RESUMO

Amorphous solid water plays an important role in our overall understanding of water's phase diagram. X-ray scattering is an important tool for characterising the different states of water, and modern storage ring and XFEL facilities have opened up new pathways to simultaneously study structure and dynamics. Here, X-ray photon correlation spectroscopy (XPCS) was used to study the dynamics of high-density amorphous (HDA) ice upon heating. We follow the structural transition from HDA to low-density amorphous (LDA) ice, by using wide-angle X-ray scattering (WAXS), for different heating rates. We used a new type of sample preparation, which allowed us to study µm-sized ice layers rather than powdered bulk samples. The study focuses on the non-equilibrium dynamics during fast heating, spontaneous transformation and crystallization. Performing the XPCS study at ultra-small angle (USAXS) geometry allows us to characterize the transition dynamics at length scales ranging from 60 nm-800 nm. For the HDA-LDA transition we observe a clear separation in three dynamical regimes, which show different dynamical crossovers at different length scales. The crystallization from LDA, instead, is observed to appear homogenously throughout the studied length scales.

20.
Addict Sci Clin Pract ; 17(1): 70, 2022 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-36494857

RESUMO

BACKGROUND: Despite their crucial role in bridging science and practice, not much is known about counselors offering treatment for Problem Gambling (PG). This study maps current treatment, the type of change techniques that are prioritized in treatment and how counselors perceive their clinical competence in their work with PG clients. METHODS: A sample of PG counselors from the healthcare and social services (N = 188, mean age: 49 years, 67% women) completed an online survey. A principal component analysis was conducted to map prioritized types of change techniques, and a multiple regression analysis was carried out to analyze predictors of counselors' role adequacy in their clinical work. RESULTS: There was a large variation in the type of treatments offered for PG (mean 3.6). Cognitive Behavioral Therapy (CBT) and Motivational Interviewing were the most common treatments offered and motivation was rated as the most important type of change technique prioritized in the treatment of PG. A principal component analysis identified four components reflecting different types of change techniques prioritized by the counselors: (1) standard CBT, e.g., gambling cognitions, craving management, and finding alternative activities, (2) assessment of PG, (3) family orientation, i.e., involvement of concerned significant others in treatment, and (4) focus on exposure strategies. Counseling more clients monthly was associated with higher levels of willingness, adequacy and legitimacy in their clinical work with clients with PG. Additionally, offering CBT was a predictor for higher role adequacy and providing counseling on the origins of and consequences of PG. CONCLUSION: There was a large heterogeneity among the treatments offered and what change techniques that were prioritized among the PG counselors. Clinical experience is of importance for developing competence in treating clients with PG. This finding suggests there could be benefits to establishing specialized, more visible treatment units where PG counselors could gain adequate clinical experience, thus increasing clinical competence for treating PG.


Assuntos
Terapia Cognitivo-Comportamental , Entrevista Motivacional , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Competência Clínica , Entrevista Motivacional/métodos , Aconselhamento/métodos , Terapia Cognitivo-Comportamental/métodos , Percepção
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