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1.
Int J Gynecol Cancer ; 2022 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-35523443

RESUMEN

For patients diagnosed with ovarian, uterine, or cervical cancer, race impacts expected outcome, with black women suffering worse survival than white women for all three malignancies. Moreover, outcomes for black women have largely worsened since the 1970s. In this narrative review, we first provide an updated summary of the incidence and survival of ovarian, uterine, and cervical cancer, with attention paid to differences between white and black patients. We then offer a theoretical framework detailing how racial disparities in outcomes for each of the gynecologic malignancies can be explained as the sum result of smaller white-black differences in experience of preventive strategies, implementation of screening efforts, early detection of symptomatic disease, and appropriate treatment. Much research has been published regarding racial disparities in each of these domains, and with this review, we seek to curate the relevant literature and present an updated understanding of disparities between black and white women with gynecologic malignancies.

2.
Artículo en Inglés | MEDLINE | ID: mdl-35543458

RESUMEN

The established method of understanding power in dentistry is based on the early Foucauldian discourse that dentistry enforces oral health discipline to the people on behalf of state power. This exhibits the hierarchy between dentists and patients, which clearly appears in clinical dentistry and effectively explains the responsibility of oral care assigned to patients. However, there presents no way to becoming free from the framework in the discourse as a resistance. Beyond the political aspect of the medico-sociological framework, this paper seeks a different way to understand power in dentistry through 'care of the self', a late Foucauldian concept. First, based on the current discussion of the dentist-patient relationship (DPR), the paper examines two trends of clinical dental treatments in South Korea. The high prevalence of dental implant and orthognathic surgery indicates that traditional prejudices including ableism and pursuit of Western beauty still remain in South Korea albeit with the society overcoming paternalism in DPRs. These dental phenomena, however, contain excesses that cannot be explained only by traditional prejudice, and this paper attempts to interpret them as the pursuit of care of the self that appears in the dentist's professionalism and the patient's self-determination. In dentistry, care of the self can be introduced in the form of empowerment, which is implemented through the improvement of oral health literacy and shared decision-making. This paper argues that this interpretation helps surmount the traditional dyadic model of the DPR and revise the understanding of power in dentistry.

3.
Disabil Rehabil ; : 1-13, 2022 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-35574615

RESUMEN

PURPOSE: To identify determinants of spoken language comprehension (SLC) in children with cerebral palsy (CP). MATERIALS AND METHODS: Cross-sectional data of 207 children with CP were included: 82 toddlers (18 months-3;11 years), 59 preschool children (4;0-5;11 years), and 66 schoolchildren (6;0-8;11 years), across all Gross Motor Function Classification System (GMFCS) levels. SLC was assessed using the Computer-Based instrument for Low motor Language Testing (C-BiLLT). Potential determinants were retrieved from medical files and through parental questionnaires. Per developmental stage, multivariable regression analyses were used to assess determinants of SLC. RESULTS: Fifty-nine percent of the children showed below average SLC. Significant determinants for SLC differed per developmental stage. In toddlers: age, motor type, functional communication and speech function (R2 = 0.637); in preschool children: functional communication, speech function and language activities (R2 = 0.820), and in schoolchildren: functional communication, intellectual functioning and arm-hand functioning (R2 = 0.807). For all developmental stages, functional mobility was not a significant determinant. CONCLUSIONS: A large proportion of children with CP across all GMFCS levels have SLC impairments. Findings indicate that SLC is strongly determined by functional communication classified with CFCS. We recommend standardized assessment and monitoring of SLC in all children with CP. IMPLICATIONS FOR REHABILITATIONChildren across all GMFCS levels can experience difficulties in spoken language comprehension.At all developmental stages, functional communication (classified with CFCS) is an important determinant of spoken language comprehension.Standardized assessment and monitoring of spoken language comprehension, language production, speech, and communication of all children with CP, is strongly recommended.When children show below average performances, especially in spoken language comprehension, intervening with speech and language therapy and guidance for parents, is advised.

5.
Radiat Res ; 2022 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-35405740

RESUMEN

Previous epidemiological studies have demonstrated elevated susceptibility to ionizing radiation in some families, thus suggesting the presence of genetic components that conferred increased rate of radiation-associated meningioma (RAM). In this study, we exome-sequenced and investigated the segregation pattern of rare deleterious variants in 11 RAM pedigrees. In addition, we performed a rare-variant association analysis in 92 unrelated familial cases of RAM that were ancestry-matched with 88 meningioma-free controls. In the pedigree analysis, we found that each family carried mostly a unique set of rare deleterious variants. A follow-up pathway analysis of the union of the genes that segregated within each of the 11 pedigrees identified a single statistically significant (q value = 7.90E-04) "ECM receptor interaction" set. In the case-control association analysis, we observed no statistically significant variants or genes after multiple testing correction; however, examination of ontological categories of the genes that associated with RAM at nominal P values <0.01 identified biologically relevant pathways such as DNA repair, cell cycle and apoptosis. These results suggest that it is unlikely that a small number of highly penetrant genes are involved in the pathogenesis of RAM. Substantially larger studies are needed to identify genetic risk variants and genes in RAM.

6.
Osteoporos Int ; 2022 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-35376989

RESUMEN

Follow-up raloxifene therapy after denosumab discontinuation resulted in a decrease in bone mass to the pre-denosumab levels and a rebound increase of bone turnover markers. The decrease in lumbar bone mineral density was particularly evident when the body mass index was low, there were previous vertebral fractures, or lumbar bone mineral density before denosumab administration was low. INTRODUCTION: Selective estrogen receptor modulators may be an alternative to bisphosphonates for treating rebound resorption after discontinuing denosumab. This study aimed to investigate the effects of follow-up raloxifene therapy after denosumab discontinuation in postmenopausal women. METHODS: This retrospective observational study included 61 patients who received 12-month follow-up raloxifene therapy after denosumab discontinuation. The primary endpoint was the bone mineral density change. The secondary endpoints were the changes in bone turnover markers and the incidence of new vertebral fractures. RESULTS: Raloxifene administration for 12 months after denosumab discontinuation resulted in a significantly lower bone mineral density at all sites compared to the level at 6 months after the last denosumab treatment (lumbar spine, - 5.48%; femoral neck, - 2.95%; total hip, - 3.52%; all, p < 0.001). The decrease in lumbar bone mineral density was particularly evident when the body mass index was low, there were previous vertebral fractures, or lumbar bone mineral density before denosumab administration was low. Marked increases in the bone turnover markers from baseline were noted after switching to raloxifene. However, no new vertebral fractures occurred during raloxifene treatment. CONCLUSIONS: Follow-up raloxifene therapy after denosumab discontinuation resulted in a decrease in bone mass to the pre-denosumab levels and a rebound increase of bone turnover markers. Therefore, raloxifene administered sequentially after denosumab discontinuation was not effective in preventing rebound phenomenon.

7.
Environ Pollut ; 305: 119181, 2022 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-35378199

RESUMEN

Arctic marine ecosystems are experiencing rapid change, such as ocean warming and enhanced pollutants. Perfluoroalkyl acids (PFAAs) arriving via long-range transport have been detected in Arctic wildlife, including seabirds which are considered sentinels of marine ecosystem health. There is evidence that PFAA exposure leads to the disruption of thyroid hormones (THs), such as thyroxine (T4) and triiodothyronine (T3), which play important roles in metabolism, incubation, and thermoregulation in seabirds. Here, we investigated relationships between PFAAs and THs [total T4 (TT4), free T4 (FT4), total T3 (TT3) and free T3 (FT3)] in blood plasma collected from 63 thick-billed murres (Uria lomvia) at a colony located in northern Hudson Bay (2016-2018). We then tested if PFAAs and TH levels were related to fitness-associated reproductive traits, such as body mass and hatch dates. PFUdA, PFOS, and PFTrDA were the dominant PFAAs in murre blood, accounting for approximately 77% of ∑PFAA. Females had higher PFAAs than males, possibly due to higher trophic feeding. While FT3 increased with PFOS, PFNA, PFDA, PFDoA, PFTeDA, ∑PFCA7, and ∑PFAA in murres, TT3 decreased with PFOS, PFDoA, and PFTeDA in males, but not females, suggesting thyroid disruption. TT3 increased with body mass, whereas several long-chain PFAAs were negatively correlated with body mass. Negative relationships between PFNA, PFDoA, PFTrDA, PFTeDA, and ∑PFAA with hatch dates may be the result of a disruption in incubation behaviour, resulting in earlier hatch dates. Consequently, TT3 concentrations were highest in males and females in 2018, a year in which PFAAs were lowest and hatch dates were delayed relative to 2017. As an Arctic seabird experiencing several indirect effects of climate change, the interaction of PFAAs on thyroid activity may cause additional stress to murres.

8.
PLoS Pathog ; 18(4): e1010155, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35404959

RESUMEN

Macaques are a commonly used model for studying immunity to human viruses, including for studies of SARS-CoV-2 infection and vaccination. However, it is unknown whether macaque antibody responses resemble the response in humans. To answer this question, we employed a phage-based deep mutational scanning approach (Phage-DMS) to compare which linear epitopes are targeted on the SARS-CoV-2 Spike protein in convalescent humans, convalescent (re-infected) rhesus macaques, mRNA-vaccinated humans, and repRNA-vaccinated pigtail macaques. We also used Phage-DMS to determine antibody escape pathways within each epitope, enabling a granular comparison of antibody binding specificities at the locus level. Overall, we identified some common epitope targets in both macaques and humans, including in the fusion peptide (FP) and stem helix-heptad repeat 2 (SH-H) regions. Differences between groups included a response to epitopes in the N-terminal domain (NTD) and C-terminal domain (CTD) in vaccinated humans but not vaccinated macaques, as well as recognition of a CTD epitope and epitopes flanking the FP in convalescent macaques but not convalescent humans. There was also considerable variability in the escape pathways among individuals within each group. Sera from convalescent macaques showed the least variability in escape overall and converged on a common response with vaccinated humans in the SH-H epitope region, suggesting highly similar antibodies were elicited. Collectively, these findings suggest that the antibody response to SARS-CoV-2 in macaques shares many features with humans, but with substantial differences in the recognition of certain epitopes and considerable individual variability in antibody escape profiles, suggesting a diverse repertoire of antibodies that can respond to major epitopes in both humans and macaques. Differences in macaque species and exposure type may also contribute to these findings.


Asunto(s)
COVID-19 , SARS-CoV-2 , Animales , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Formación de Anticuerpos , COVID-19/prevención & control , Vacunas contra la COVID-19 , Epítopos , Humanos , Macaca mulatta , Glicoproteína de la Espiga del Coronavirus , Vacunación
9.
Sci Data ; 9(1): 175, 2022 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-35440585

RESUMEN

The dopaminergic system undergoes major reorganization during development, a period especially vulnerable to mental disorders. Forebrain neurons expressing dopamine 1 and 2 receptors (D1R and D2R, respectively) play a key role in this system. However, neuroanatomical information about the typical development of these neurons is sparse and scattered across publications investigating one or a few brain regions. We here present a public online collection of microscopic images of immunohistochemically stained serial sections from male and female mice at five stages of development (postnatal day 17 (P17), P25, P35, P49, and adult), showing the distribution of D1R and D2R expressing neurons across the forebrain. All images from adult brains are registered to the Allen Mouse brain Common Coordinate Framework, while images from P17-P35 age groups are registered to spatially modified atlas versions matching the morphology of young brains. This online resource provides microscopic visualization of the developing dopaminergic system in mice, which is suitable as a benchmark reference for performing new experiments and building computational models of the brain.


Asunto(s)
Dopamina , Prosencéfalo , Receptores de Dopamina D1 , Receptores de Dopamina D2 , Animales , Dopamina/metabolismo , Ratones , Neuronas/metabolismo , Neuronas/fisiología , Prosencéfalo/crecimiento & desarrollo , Prosencéfalo/metabolismo , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D2/metabolismo
10.
Nat Immunol ; 23(5): 781-790, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35383307

RESUMEN

Although mRNA vaccine efficacy against severe coronavirus disease 2019 remains high, variant emergence has prompted booster immunizations. However, the effects of repeated exposures to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antigens on memory T cells are poorly understood. Here, we utilize major histocompatibility complex multimers with single-cell RNA sequencing to profile SARS-CoV-2-responsive T cells ex vivo from humans with one, two or three antigen exposures, including vaccination, primary infection and breakthrough infection. Exposure order determined the distribution between spike-specific and non-spike-specific responses, with vaccination after infection leading to expansion of spike-specific T cells and differentiation to CCR7-CD45RA+ effectors. In contrast, individuals after breakthrough infection mount vigorous non-spike-specific responses. Analysis of over 4,000 epitope-specific T cell antigen receptor (TCR) sequences demonstrates that all exposures elicit diverse repertoires characterized by shared TCR motifs, confirmed by monoclonal TCR characterization, with no evidence for repertoire narrowing from repeated exposure. Our findings suggest that breakthrough infections diversify the T cell memory repertoire and current vaccination protocols continue to expand and differentiate spike-specific memory.

11.
Eur Rev Med Pharmacol Sci ; 26(7): 2511-2517, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35442466

RESUMEN

OBJECTIVE: The aim of this study is to compare the risk of venous thromboembolic events (VTE) between patients suspending and continuing estrogen therapy perioperatively, in male to female gender-affirming surgery (vaginoplasty). MATERIALS AND METHODS: The authors conducted a systematic review and meta-analysis of existing research on male to female gender-affirming study, which compared the risk of VTE among the usage of estrogen perioperatively. RESULTS: A total of 209 studies were identified as potentially eligible among PubMed, Embase, and Cochrane library databases. Among the studies, 191 studies were excluded due to their abstract inappropriateness. Out of the remaining 18 studies, only 3 articles were eligible and were finally included. Meta-analysis was performed and showed odds ratio of 0.77 (95% CI: 0.04, 14.01). CONCLUSIONS: Perioperative estrogen therapy does not increase VTE risk on male to female gender-affirming surgery. Therefore, estrogen therapy may be continued perioperatively in vaginoplasty. More prospective studies are needed.


Asunto(s)
Personas Transgénero , Tromboembolia Venosa , Trombosis de la Vena , Estrógenos/efectos adversos , Femenino , Terapia de Reemplazo de Hormonas , Humanos , Masculino , Tromboembolia Venosa/inducido químicamente , Tromboembolia Venosa/epidemiología
12.
Eur Rev Med Pharmacol Sci ; 26(7): 2395-2398, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35442493

RESUMEN

OBJECTIVE: Herein, we introduce the infusion direction manipulation technique and the infusion off technique. These relatively simple methods control intra-vitreal fluid flow direction and turbulence and release negative pressure in the microforceps to facilitate handling of the internal limiting membrane. The aim of this study is to introduce an effective and uncomplicated method to handle the internal limiting membrane (ILM) during the temporal inverted ILM flap and free ILM flap techniques in macular hole surgery by controlling the direction and status of the infusion. MATERIALS AND METHODS: The direction of the infusion flow was controlled with a free finger (usually the 4th finger) during the inverted ILM flap surgery to stabilize the flap location during the fluid-air exchange. A valved trocar was used, and the infusion was discontinued during the free ILM flap surgery. Turbulence was minimized, and negative pressure around the head-shaft junction of the microforceps was released. RESULTS: The ILM flap remained stable in all patients who underwent macular hole surgery with our technique. CONCLUSIONS: Infusion direction manipulation technique and infusion off technique are efficient and simple methods to handle the ILM during ILM surgery.


Asunto(s)
Perforaciones de la Retina , Membrana Basal/cirugía , Humanos , Perforaciones de la Retina/complicaciones , Perforaciones de la Retina/cirugía , Estudios Retrospectivos , Tomografía de Coherencia Óptica/métodos , Agudeza Visual , Vitrectomía/métodos
13.
Vaccine ; 40(21): 2960-2969, 2022 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-35428500

RESUMEN

The enhanced transmissibility and immune evasion associated with emerging SARS-CoV-2 variants demands the development of next-generation vaccines capable of inducing superior protection amid a shifting pandemic landscape. Since a portion of the global population harbors some level of immunity from vaccines based on the original Wuhan-Hu-1 SARS-CoV-2 sequence or natural infection, an important question going forward is whether this immunity can be boosted by next-generation vaccines that target emerging variants while simultaneously maintaining long-term protection against existing strains. Here, we evaluated the immunogenicity of INO-4800, our synthetic DNA vaccine candidate for COVID-19 currently in clinical evaluation, and INO-4802, a next-generation DNA vaccine designed to broadly target emerging SARS-CoV-2 variants, as booster vaccines in nonhuman primates. Rhesus macaques primed over one year prior with the first-generation INO-4800 vaccine were boosted with either INO-4800 or INO-4802 in homologous or heterologous prime-boost regimens. Both boosting schedules led to an expansion of T cells and antibody responses which were characterized by improved neutralizing and ACE2 blocking activity across wild-type SARS-CoV-2 as well as multiple variants of concern. These data illustrate the durability of immunity following vaccination with INO-4800 and additionally support the use of either INO-4800 or INO-4802 in prime-boost regimens.


Asunto(s)
COVID-19 , Vacunas de ADN , Vacunas Virales , Animales , Formación de Anticuerpos , COVID-19/prevención & control , Vacunas contra la COVID-19 , Humanos , Macaca mulatta , Ratones , Ratones Endogámicos BALB C , SARS-CoV-2 , Vacunación
14.
Phys Rev Lett ; 128(13): 131802, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35426701

RESUMEN

Axionlike particles (ALPs) are predicted in many extensions of the standard model, and their masses can naturally be well below the electroweak scale. In the presence of couplings to electroweak bosons, these particles could be emitted in flavor-changing B meson decays. We report herein a search for an ALP, a, in the reaction B^{±}→K^{±}a, a→γγ using data collected by the BABAR experiment at SLAC. No significant signal is observed, and 90% confidence level upper limits on the ALP coupling to electroweak bosons are derived as a function of ALP mass, improving current constraints by several orders of magnitude in the range 0.175 GeV

15.
Environ Res ; 212(Pt A): 113190, 2022 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-35367428

RESUMEN

Arctic species encounter multiple stressors including climate change and environmental contaminants. Some contaminants may disrupt hormones that govern the behavioural responses of wildlife to climatic variation, and thus the capacity of species to respond to climate change. We investigated correlative interactions between legacy and emerging persistent organic pollutants (POPs), mercury (Hg), hormones and behaviours, in thick-billed murres (Uria lomvia) (N = 163) breeding in northern Hudson Bay (2016-2018). The blood profile of the murres was dominated by methylmercury (MeHg), followed by much lower levels of sum (∑) 35 polychlorinated biphenyls (PCBs), hexachlorobenzene (HCB) and p,p'-dichlorodiphenyltrichloroethylene (DDE), polybrominated diphenyl ethers (PBDEs) BDE-47, -99 and BDE-100; all other measured organochlorine pesticides and replacement brominated flame retardants had low concentrations if detected. Inter-annual variations occurred in MeHg, circulating triiodothyronine (T3), thyroxine (T4), and the foraging behaviours of the murres, identified using GPS-accelerometers. Compared to the 50-year mean date (1971-2021) for 50% of sea-ice coverage in Hudson Bay, sea-ice breakup was 1-2 weeks earlier (2016, 2017) or comparable (2018). Indeed, 2017 was the earliest year on record. Consistent with relationships identified individually between MeHg and total T3, and T3 and foraging behaviour, a direct interaction between these three parameters was evident when all possible interactions among measured chemical pollutants, hormones, and behaviours of the murres were considered collectively (path analysis). When murres were likely already stressed due to early sea-ice breakup (2016, 2017), blood MeHg influenced circulating T3 that in turn reduced foraging time underwater. We conclude that when sea-ice breaks up early in the breeding season, Hg may interfere with the ability of murres to adjust their foraging behaviour via T3 in relation to variation in sea-ice.

16.
J Phys Condens Matter ; 34(26)2022 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-35385840

RESUMEN

The nanoscale patterns produced by bombardment of the (100) surface of silicon with a 2 keV Kr ion beam are investigated both experimentally and theoretically. In our experiments, we find that the patterns observed at high ion fluences depend sensitively on the angle of incidence Θ. For Θ values between 74° and 85°, we observe five decidedly different kinds of morphologies, including triangular nanostructures traversed by parallel-mode ripples, long parallel ridges decorated by short-wavelength ripples, and a remarkable mesh-like morphology. In contrast, only parallel-mode ripples are present for low ion fluences except for Θ = 85°. Our simulations show that triangular nanostructures that closely resemble those in our experiments emerge if a linearly dispersive term and a conserved Kuramoto-Sivashinsky nonlinearity are appended to the usual equation of motion. We find ridges traversed by ripples, on the other hand, in simulations of the Harrison-Pearson-Bradley equation (Harrisonet al2017Phys. Rev.E96032804). For Θ = 85°, the solid surface is apparently stable and simulations of an anisotropic Edwards-Wilkinson equation yield surfaces similar to those seen in our experiments. Explaining the other two kinds of patterns we find in our experiments remains a challenge for future theoretical work.

17.
Ann Oncol ; 2022 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-35398288

RESUMEN

BACKGROUND: Pancreatic cancer presents as advanced disease in >80% of patients; yet, appropriate ages to consider prevention and early detection strategies are poorly defined. We investigated age-specific associations and attributable risks of pancreatic cancer for established modifiable and non-modifiable risk factors. PATIENTS AND METHODS: We included 167 483 participants from two prospective US cohort studies with 1190 incident cases of pancreatic cancer during >30 years of follow-up; 5107 pancreatic cancer cases and 8845 control participants of European ancestry from a completed multicenter genome-wide association study (GWAS); and 248 893 pancreatic cancer cases documented in the US Surveillance, Epidemiology, and End Results (SEER) Program. Across different age categories, we investigated cigarette smoking, obesity, diabetes, height, and non-O blood group in the prospective cohorts; weighted polygenic risk score of 22 previously identified single nucleotide polymorphisms in the GWAS; and male sex and black race in the SEER Program. RESULTS: In the prospective cohorts, all five risk factors were more strongly associated with pancreatic cancer risk among younger participants, with associations attenuated among those aged >70 years. The hazard ratios comparing participants with three to five risk factors with those with no risk factors were 9.24 [95% confidence interval (CI) 4.11-20.77] among those aged ≤60 years, 3.00 (95% CI 1.85-4.86) among those aged 61-70 years, and 1.46 (95% CI 1.10-1.94) among those aged >70 years (Pheterogeneity = 3×10-5). These factors together were related to 65.6%, 49.7%, and 17.2% of incident pancreatic cancers in these age groups, respectively. In the GWAS and the SEER Program, the associations with the polygenic risk score, male sex, and black race were all stronger among younger individuals (Pheterogeneity ≤0.01). CONCLUSIONS: Established risk factors are more strongly associated with earlier-onset pancreatic cancer, emphasizing the importance of age at initiation for cancer prevention and control programs targeting this highly lethal malignancy.

18.
Sci Total Environ ; 834: 155221, 2022 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-35427623

RESUMEN

Global climate change has led to profound alterations of the Arctic environment and ecosystems, with potential secondary effects on mercury (Hg) within Arctic biota. This review presents the current scientific evidence for impacts of direct physical climate change and indirect ecosystem change on Hg exposure and accumulation in Arctic terrestrial, freshwater, and marine organisms. As the marine environment is elevated in Hg compared to the terrestrial environment, terrestrial herbivores that now exploit coastal/marine foods when terrestrial plants are iced over may be exposed to higher Hg concentrations. Conversely, certain populations of predators, including Arctic foxes and polar bears, have shown lower Hg concentrations related to reduced sea ice-based foraging and increased land-based foraging. How climate change influences Hg in Arctic freshwater fishes is not clear, but for lacustrine populations it may depend on lake-specific conditions, including interrelated alterations in lake ice duration, turbidity, food web length and energy sources (benthic to pelagic), and growth dilution. In several marine mammal and seabird species, tissue Hg concentrations have shown correlations with climate and weather variables, including climate oscillation indices and sea ice trends; these findings suggest that wind, precipitation, and cryosphere changes that alter Hg transport and deposition are impacting Hg concentrations in Arctic marine organisms. Ecological changes, including northward range shifts of sub-Arctic species and altered body condition, have also been shown to affect Hg levels in some populations of Arctic marine species. Given the limited number of populations and species studied to date, especially within Arctic terrestrial and freshwater systems, further research is needed on climate-driven processes influencing Hg concentrations in Arctic ecosystems and their net effects. Long-term pan-Arctic monitoring programs should consider ancillary datasets on climate, weather, organism ecology and physiology to improve interpretation of spatial variation and time trends of Hg in Arctic biota.

19.
Eur J Appl Physiol ; 2022 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-35303160

RESUMEN

OBJECTIVES: Examine the acute effects (pre-, during, post-intervention) of two different intensities of aerobic exercise or rest on autonomic, oculomotor, and vestibular function and symptom burden in patients with a recent sport-related concussion (SRC) and compare their responses to sex-matched, age-stratified, non-concussed (HEALTHY) student-athletes. METHODS: Student-athletes between the ages of 13 and 18 that presented to the sports medicine clinic within Day 3-7 post-SRC and from local schools were recruited for a randomized controlled trial (RCT). The participants were administered the Vestibular/Ocular Motor Screening (VOMS), King-Devick (K-D), and Post-Concussion Symptom Scale (PCSS) before and after the intervention. Heart rate variability (HRV) and mean arterial pressure (MAP) were collected before, during, and after the intervention. The intervention was either a single, 20-min session of treadmill walking at 40% (40HR) or 60% of age-predicted max heart rate (60HR), or seated, rest (NOEX). RESULTS: 30 participants completed the intervention with the SRC group treated 4.5 ± 1.3 days post-injury. Pre-exercise HRV and MAP were significantly different (p's < 0.001) during treatment but returned to pre-exercise values within 5 min of recovery in both the SRC and HEALTHY groups. Both the SRC and HEALTHY groups exhibited similar reductions pre- to post-intervention for symptom severity and count (p's < 0.05), three VOMS items (p's < 0.05) but not K-D time. CONCLUSIONS: To date, this is the first adolescent RCT to report the acute, systemic effects of aerobic exercise on recently concussed adolescent athletes. The interventions appeared safe in SRC participants, were well-tolerated, and provided brief therapeutic benefit. TRIAL REGISTRATION: Clinicaltrials.gov Identifier NCT03575455.

20.
Phys Rev Lett ; 128(9): 091804, 2022 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-35302790

RESUMEN

We report on the first search for electron-muon lepton flavor violation (LFV) in the decay of a b quark and b antiquark bound state. We look for the LFV decay ϒ(3S)→e^{±}µ^{∓} in a sample of 118 million ϒ(3S) mesons from 27 fb^{-1} of data collected with the BABAR detector at the SLAC PEP-II e^{+}e^{-} collider operating with a 10.36 GeV center-of-mass energy. No evidence for a signal is found, and we set a limit on the branching fraction B[ϒ(3S)→e^{±}µ^{∓}]<3.6×10^{-7} at 90% C. L. This result can be interpreted as a limit Λ_{NP}/g_{NP}^{2}>80 TeV on the energy scale Λ_{NP} divided by the coupling-squared g_{NP}^{2} of relevant new physics (NP).

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