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1.
Circulation ; 149(13): 1033-1052, 2024 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-38527130

RESUMO

The use of venoarterial extracorporeal membrane oxygenation (VA-ECMO) for temporary mechanical circulatory support in various clinical scenarios has been increasing consistently, despite the lack of sufficient evidence regarding its benefit and safety from adequately powered randomized controlled trials. Although the ARREST trial (Advanced Reperfusion Strategies for Patients with Out-of-Hospital Cardiac Arrest and Refractory Ventricular Fibrillation) and a secondary analysis of the PRAGUE OHCA trial (Prague Out-of-Hospital Cardiac Arrest) provided some evidence in favor of VA-ECMO in the setting of out-of-hospital cardiac arrest, the INCEPTION trial (Early Initiation of Extracorporeal Life Support in Refractory Out-of-Hospital Cardiac Arrest) has not found a relevant improvement of short-term mortality with extracorporeal cardiopulmonary resuscitation. In addition, the results of the recently published ECLS-SHOCK trial (Extracorporeal Life Support in Cardiogenic Shock) and ECMO-CS trial (Extracorporeal Membrane Oxygenation in the Therapy of Cardiogenic Shock) discourage the routine use of VA-ECMO in patients with infarct-related cardiogenic shock. Ongoing clinical trials (ANCHOR [Assessment of ECMO in Acute Myocardial Infarction Cardiogenic Shock, NCT04184635], REVERSE [Impella CP With VA ECMO for Cardiogenic Shock, NCT03431467], UNLOAD ECMO [Left Ventricular Unloading to Improve Outcome in Cardiogenic Shock Patients on VA-ECMO, NCT05577195], PIONEER [Hemodynamic Support With ECMO and IABP in Elective Complex High-risk PCI, NCT04045873]) may clarify the usefulness of VA-ECMO in specific patient subpopulations and the efficacy of combined mechanical circulatory support strategies. Pending further data to refine patient selection and management recommendations for VA-ECMO, it remains uncertain whether the present usage of this device improves outcomes.


Assuntos
Oxigenação por Membrana Extracorpórea , Infarto do Miocárdio , Parada Cardíaca Extra-Hospitalar , Intervenção Coronária Percutânea , Humanos , Oxigenação por Membrana Extracorpórea/métodos , Infarto do Miocárdio/etiologia , Parada Cardíaca Extra-Hospitalar/terapia , Parada Cardíaca Extra-Hospitalar/etiologia , Choque Cardiogênico/diagnóstico , Choque Cardiogênico/terapia , Ensaios Clínicos como Assunto
2.
Nature ; 572(7768): 194-198, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31341281

RESUMO

Soil organisms are a crucial part of the terrestrial biosphere. Despite their importance for ecosystem functioning, few quantitative, spatially explicit models of the active belowground community currently exist. In particular, nematodes are the most abundant animals on Earth, filling all trophic levels in the soil food web. Here we use 6,759 georeferenced samples to generate a mechanistic understanding of the patterns of the global abundance of nematodes in the soil and the composition of their functional groups. The resulting maps show that 4.4 ± 0.64 × 1020 nematodes (with a total biomass of approximately 0.3 gigatonnes) inhabit surface soils across the world, with higher abundances in sub-Arctic regions (38% of total) than in temperate (24%) or tropical (21%) regions. Regional variations in these global trends also provide insights into local patterns of soil fertility and functioning. These high-resolution models provide the first steps towards representing soil ecological processes in global biogeochemical models and will enable the prediction of elemental cycling under current and future climate scenarios.


Assuntos
Mapeamento Geográfico , Nematoides/classificação , Nematoides/isolamento & purificação , Solo/parasitologia , Animais , Biomassa , Carbono/metabolismo , Nematoides/química , Filogeografia , Reprodutibilidade dos Testes , Incerteza
3.
Proc Natl Acad Sci U S A ; 119(29): e2207020119, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35858345

RESUMO

Changes in Ca2+ influx during proinflammatory stimulation modulates cellular responses, including the subsequent activation of inflammation. Whereas the involvement of Ca2+ has been widely acknowledged, little is known about the role of Na+. Ranolazine, a piperazine derivative and established antianginal drug, is known to reduce intracellular Na+ as well as Ca2+ levels. In stable coronary artery disease patients (n = 51) we observed reduced levels of high-sensitive C-reactive protein (CRP) 3 mo after the start of ranolazine treatment (n = 25) as compared to the control group. Furthermore, we found that in 3,808 acute coronary syndrome patients of the MERLIN-TIMI 36 trial, individuals treated with ranolazine (1,934 patients) showed reduced CRP values compared to placebo-treated patients. The antiinflammatory effects of sodium modulation were further confirmed in an atherosclerotic mouse model. LDL-/- mice on a high-fat diet were treated with ranolazine, resulting in a reduced atherosclerotic plaque burden, increased plaque stability, and reduced activation of the immune system. Pharmacological Na+ inhibition by ranolazine led to reduced express of adhesion molecules and proinflammatory cytokines and reduced adhesion of leukocytes to activated endothelium both in vitro and in vivo. We demonstrate that functional Na+ shuttling is required for a full cellular response to inflammation and that inhibition of Na+ influx results in an attenuated inflammatory reaction. In conclusion, we demonstrate that inhibition of Na+-Ca2+ exchange during inflammation reduces the inflammatory response in human endothelial cells in vitro, in a mouse atherosclerotic disease model, and in human patients.


Assuntos
Síndrome Coronariana Aguda , Proteína C-Reativa , Fármacos Cardiovasculares , Doença da Artéria Coronariana , Ranolazina , Bloqueadores dos Canais de Sódio , Sódio , Síndrome Coronariana Aguda/tratamento farmacológico , Animais , Proteína C-Reativa/análise , Proteína C-Reativa/metabolismo , Fármacos Cardiovasculares/farmacologia , Fármacos Cardiovasculares/uso terapêutico , Doença da Artéria Coronariana/tratamento farmacológico , Células Endoteliais/metabolismo , Humanos , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Camundongos , Ranolazina/farmacologia , Ranolazina/uso terapêutico , Sódio/metabolismo , Bloqueadores dos Canais de Sódio/farmacologia , Bloqueadores dos Canais de Sódio/uso terapêutico
4.
Nat Mater ; 22(7): 848-852, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37106132

RESUMO

Solid-state electrolytes overcome many challenges of present-day lithium ion batteries, such as safety hazards and dendrite formation1,2. However, detailed understanding of the involved lithium dynamics is missing due to a lack of in operando measurements with chemical and interfacial specificity. Here we investigate a prototypical solid-state electrolyte using linear and nonlinear extreme-ultraviolet spectroscopies. Leveraging the surface sensitivity of extreme-ultraviolet-second-harmonic-generation spectroscopy, we obtained a direct spectral signature of surface lithium ions, showing a distinct blueshift relative to bulk absorption spectra. First-principles simulations attributed the shift to transitions from the lithium 1 s state to hybridized Li-s/Ti-d orbitals at the surface. Our calculations further suggest a reduction in lithium interfacial mobility due to suppressed low-frequency rattling modes, which is the fundamental origin of the large interfacial resistance in this material. Our findings pave the way for new optimization strategies to develop these electrochemical devices via interfacial engineering of lithium ions.


Assuntos
Eletrólitos , Lítio , Fontes de Energia Elétrica , Engenharia , Software
5.
Theor Appl Genet ; 137(5): 99, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38598016

RESUMO

KEY MESSAGE: We find evidence of selection for local adaptation and extensive genotype-by-environment interaction in the potato National Chip Processing Trial (NCPT). We present a novel method for dissecting the interplay between selection, local adaptation and environmental response in plant breeding schemes. Balancing local adaptation and the desire for widely adapted cultivars is challenging for plant breeders and makes genotype-by-environment interactions (GxE) an important target of selection. Selecting for GxE requires plant breeders to evaluate plants across multiple environments. One way breeders have accomplished this is to test advanced materials across many locations. Public potato breeders test advanced breeding material in the National Chip Processing Trial (NCPT), a public-private partnership where breeders from ten institutions submit advanced chip lines to be evaluated in up to ten locations across the country. These clones are genotyped and phenotyped for important agronomic traits. We used these data to interrogate the NCPT for GxE. Further, because breeders submitting clones to the NCPT select in a relatively small geographic range for the first 3 years of selection, we examined these data for evidence of incidental selection for local adaptation, and the alleles underlying it, using an environmental genome-wide association study (envGWAS). We found genomic regions associated with continuous environmental variables and discrete breeding programs, as well as regions of the genome potentially underlying GxE for yield.


Assuntos
Interação Gene-Ambiente , Estudo de Associação Genômica Ampla , Melhoramento Vegetal , Genótipo , Fenótipo
6.
Phys Chem Chem Phys ; 26(15): 11980-11987, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38573245

RESUMO

The L2,3-edge X-ray absorption spectra of late transition metals such as Cu, Ag, and Au exhibit absorption onsets lower in energy for higher oxidation states, which is at odds with the measured spectra of earlier transition metals. Time-dependent density functional theory calculations for Cu2+/Cu+ reveal a larger 2p core-exciton binding energy for Cu2+, overshadowing shifts in single-particle excitation energies with respect to Cu+. We explore this phenomenon in a Cu+ metal-organic framework with ∼12% Cu2+ defects and find that corrections with self-consistent excited-state total energy differences provide accurate XAS peak alignment.

7.
J Minim Invasive Gynecol ; 31(5): 364, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38307223

RESUMO

STUDY OBJECTIVE: To demonstrate reproducible procedures for efficient single-incision sling insertion and troubleshooting. DESIGN: Narrated video footage with stepwise demonstration of single-incision sling insertion technique with anchor system. SETTING: The mesh midurethral sling is a highly effective and safe procedure that is considered the gold standard for surgical treatment of stress urinary incontinence. Retropubic and transobturator approaches for midurethral slings have similar subjective cure rates with differing surgical risk profiles [1,2]. The retropubic route has a higher risk of injury to the bladder, nerves, and vascular structures, whereas the obturator approach carries a risk of groin or thigh pain [3-5]. Use of a single-incision sling decreases these risks and allows flexibility to perform the procedure without sedation or general anesthesia. Recent literature demonstrates similar subjective and objective success and safety of single-incision slings compared with both retropubic and transobturator approaches, although long-term data are forthcoming [5]. INTERVENTIONS: We demonstrate a stepwise approach for the insertion of a single-incision sling using a helical trocar. Easily reproducible procedures for setup and sling anchor management allow for efficient placement without assistance. In addition, we outline hand positioning, trocar management, and anchor deployment with troubleshooting techniques for potential placement difficulties. Finally, we review methods for sling tensioning to prevent complications such as voiding dysfunction and mesh or suture exposures. CONCLUSION: Given that single-incision slings are more likely to be performed under local anesthesia and are less invasive with decreased recovery time, it has the potential to become the preferred approach in the future. This video demonstrates clear and detailed steps to facilitate successful placement of the single-incision mesh midurethral sling.


Assuntos
Slings Suburetrais , Incontinência Urinária por Estresse , Humanos , Incontinência Urinária por Estresse/cirurgia , Feminino , Procedimentos Cirúrgicos em Ginecologia/métodos , Procedimentos Cirúrgicos em Ginecologia/instrumentação
8.
J Am Pharm Assoc (2003) ; : 102131, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38796160

RESUMO

BACKGROUND: Pharmacy accessibility is crucial for equity in healthcare access because community pharmacists may reach individuals who do not have access to other healthcare providers. OBJECTIVE: To determine whether spatial access to pharmacies differs among racial/ethnic groups across the rural-urban continuum. METHODS: We obtained a 30% random sample of the Research Triangle Institute (RTI) synthetic population, sampled at the census block level. For each individual, we defined optimal pharmacy access as having a driving distance ≤2 miles to the closest pharmacy in urban counties, ≤5 miles in suburban counties, and ≤10 miles in rural counties. We used a logistic regression model to measure the association between race/ethnicity and pharmacy access, while controlling for racial/ethnic composition of the census tract, Area Deprivation Index, income, age, gender, and US region. The model included an interaction between race/ethnicity and urbanicity to evaluate whether racial/ethnic inequities differed across the rural-urban continuum. RESULTS: The sample included 90,749,446 individuals of whom 80.6% had optimal pharmacy access. Racial/ethnic inequities in pharmacy access differed across the rural-urban continuum (p-value for interaction= <0.0001). In rural areas, Black (OR 0.87; 95%CI 0.86-0.87), Hispanic (OR 0.80; 95%CI 0.79-0.80), and Indigenous (OR 0.47; 95%CI 0.47-0.48) individuals had lower odds of optimal pharmacy access, compared to White individuals. Hispanic (OR 0.96; 95%CI 0.96-0.97) and Indigenous individuals (OR 0.75; 95%CI 0.75-0.76) had lower odds of optimal pharmacy access compared to White individuals in suburban areas. In Western states, Asian had lower odds of optimal pharmacy access in suburban (OR 0.88; 95%CI 0.86-0.90) and rural areas (OR 0.91; 95%CI 0.87-0.95) compared to White Individuals. CONCLUSIONS: Racial/ethnic inequities in spatial access to community pharmacies vary between urban and rural communities. Underrepresented racial/ethnic groups have significantly lower pharmacy access in rural and some suburban areas, but not in urban areas.

9.
FASEB J ; 36(10): e22532, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36063138

RESUMO

Interleukin-4 (IL-4) and its receptors (IL-4R) promote the proliferation and polarization of macrophages. However, it is unknown if IL-4R also influences monocyte homeostasis and if steady state IL-4 levels are sufficient to affect monocytes. Employing full IL-4 receptor alpha knockout mice (IL-4Rα-/- ) and mice with a myeloid-specific deletion of IL-4Rα (IL-4Rαf/f LysMcre ), we show that IL-4 acts as a homeostatic factor regulating circulating monocyte numbers. In the absence of IL-4Rα, murine monocytes in blood were reduced by 50% without altering monocytopoiesis in the bone marrow. This reduction was accompanied by a decrease in monocyte-derived inflammatory cytokines in the plasma. RNA sequencing analysis and immunohistochemical staining of splenic monocytes revealed changes in mRNA and protein levels of anti-apoptotic factors including BIRC6 in IL-4Rα-/- knockout animals. Furthermore, assessment of monocyte lifespan in vivo measuring BrdU+ cells revealed that the lifespan of circulating monocytes was reduced by 55% in IL-4Rα-/- mice, whereas subcutaneously applied IL-4 prolonged it by 75%. Treatment of human monocytes with IL-4 reduced the amount of dying monocytes in vitro. Furthermore, IL-4 stimulation reduced the phosphorylation of proteins involved in the apoptosis pathway, including the phosphorylation of the NFκBp65 protein. In a cohort of human patients, serum IL-4 levels were significantly associated with monocyte counts. In a sterile peritonitis model, reduced monocyte counts resulted in an attenuated recruitment of monocytes upon inflammatory stimulation in IL-4Rαf/f LysMcre mice without changes in overall migratory function. Thus, we identified a homeostatic role of IL-4Rα in regulating the lifespan of monocytes in vivo.


Assuntos
Interleucina-4/metabolismo , Monócitos , Receptores de Superfície Celular/metabolismo , Transdução de Sinais , Animais , Homeostase , Humanos , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Monócitos/metabolismo
10.
Surg Endosc ; 37(6): 4651-4657, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36869264

RESUMO

INTRODUCTION: In patients with history of cancer adrenal metastases can be found in up to 70% of adrenal tumors detected during follow-up. Currently, laparoscopic adrenalectomy (LA) is considered the gold standard approach for benign adrenal tumors but is still controversial in malignant disease. Depending on the patient's oncological status, adrenalectomy might be a possible treatment option. Our objective was to analyze the results of LA for adrenal metastasis from solid tumors in two referral centers. METHODS: Retrospective analysis of 17 patients with non-primary adrenal malignancy treated with LA between 2007 and 2019 was performed. Demographic and primary tumor data, type of metastasis, morbidity, disease recurrence and evolution were evaluated. Patients were compared according to type of metastases: synchronous (< 6 months) vs metachronous (≥ 6 months). RESULTS: 17 patients were included. Median metastatic adrenal tumor size was 4 cm (IQR, 3-5.4). We had one conversion to open surgery. Recurrence was found in 6 patients with one recurring in the adrenal bed. The median OS was 24 (IQR, 10.5-60.5) months and 5-year OS was 61.4% (95%CI: 36.7%-81.4%). Patients with metachronous metastases had better overall survival vs. patients with synchronous metastases (87% vs. 14%, p = 0.0037). CONCLUSION: LA for adrenal metastases is a procedure associated with low morbidity and acceptable oncologic outcomes. Based on our results, seems reasonable to offer this procedure to carefully selected patients, mainly those with metachronous presentation. Indication of LA must be done on a case by case evaluation in the context of a multidisciplinary tumor board.


Assuntos
Neoplasias das Glândulas Suprarrenais , Laparoscopia , Humanos , Adrenalectomia/métodos , Estudos Retrospectivos , Resultado do Tratamento , Recidiva Local de Neoplasia/cirurgia , Neoplasias das Glândulas Suprarrenais/cirurgia
11.
BMC Vet Res ; 19(1): 121, 2023 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-37573333

RESUMO

BACKGROUND: Hard ticks infesting cattle are vectors of Tick-borne diseases that causes major public health problems and considerable socioeconomic losses to the livestock industry in tropical and subtropical countries. A repeated cross-sectional study was carried out by collecting ticks on cattle during the wet and dry seasons from January to August 2021 in order to determine hard tick prevalence, distribution, and abundance on cattle in Kilombero and Iringa Districts of Tanzania. The collected ticks were identified morphologically using published morphological keys under a stereomicroscope and confirmed by polymerase chain reaction (PCR) and sequencing. RESULTS: Out of 740 examined cattle, 304, (41.08%) were infested with ticks. In total, 1,780 ticks were counted on one side of the animal's body and doubled, whereby resulting in a total of 3,560 ticks were recorded. Individual tick burden ranged from n = 2 to 82 ticks per animal, with a mean tick burden of n = 11.7 ± 0.68 per animal. A total of 1,889 ticks were collected from infected cattle including 109 additional ticks observed while collecting ticks based on the animal's posture when restrained to the ground. Out of 1,889 ticks, nine species from three genera were identified morphologically: 1,377 fit in the genus Rhipicephalus, 459 to the genus of Amblyomma, and 53 to the genus Hyalomma. Rhipicephalus microplus was the most prevalent (n = 909, 48.1%), followed by Rhipicephalus evertsi (n = 310, 16.4%), Amblyomma lepidum (n = 310, 16.4%), Rhipicephalus appendiculatus (n = 140, 7.4%), Amblyomma gemma (n = 120, 6.4%), Hyalomma rufipes (n = 50, 2.6%), Amblyomma variegatum (n = 29, 1.5%), Rhipicephalus decoloratus (n = 18, 1.0%), while the least common was Hyalomma albiparmatum (n = 3, 0.2%). Tick diversity was higher in Iringa compared to Kilombero District. Tick prevalence was higher in wet season (n = 148, 41.11%). Ticks were widely distributed in different parts of the host body, with the highest distribution on zone 4 (n = 1,060, 56.11%), which includes groin, flank, abdomen, and around inner thigh of the hind legs and the lowest distribution on zone 2 (n = 14, 0.74%), which includes the back surface of the body. Both Amblyomma lepidum and Rhipicephalus microplus species were found in all the five body zones, and with the highest proportions recorded on zone 4: A. lepidum (n = 209, 67.42%) and R. microplus (n = 714, 78.55%). The nine tick species identified morphologically were also confirmed using molecular methods. However, during sequencing, two species (Rhipicephalus appendiculatus and R. decoloratus) had poor quality sequences and were excluded from the sequence analysis. Sequencing results indicated high nucleotide identity (96-100%) with sequences available in GenBank and Barcode of Life Database (BOLD). The phylogenetic analysis of partial mitochondrial COI and 16S rRNA gene sequences of ticks were used to confirm the morphological identification. CONCLUSION: The results showed a high burden of tick infestation on cattle, which could reduce animal production and potentially increase the risk of tick-borne diseases. Therefore, it is necessary to explore the epidemiological and molecular aspects of various tick species in other regions of Tanzania.


Assuntos
Doenças dos Bovinos , Ixodidae , Rhipicephalus , Infestações por Carrapato , Doenças Transmitidas por Carrapatos , Animais , Bovinos , RNA Ribossômico 16S , Tanzânia/epidemiologia , Estudos Transversais , Filogenia , Doenças dos Bovinos/epidemiologia , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/veterinária , Amblyomma , Doenças Transmitidas por Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/veterinária
12.
Med Vet Entomol ; 37(2): 316-329, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36543747

RESUMO

Triatoma maculata (Hemiptera, Reduviidae, Triatominae) occurs across dry-to-semiarid ecoregions of northern South America, where it transmits Trypanosoma cruzi, causative agent of Chagas disease. Using 207 field-caught specimens from throughout the species' range, mitochondrial(mt) DNA sequence data, and cytogenetics, we investigated inter-population genetic diversity and the phylogenetic affinities of T. maculata. Mitochondrial DNA sequence analyses (cytb and nd4) disclosed a monophyletic T. maculata clade encompassing three distinct geographic groups: Roraima formation (Guiana shield), Orinoco basin, and Magdalena basin (trans-Andean). Between-group cytb distances (11.0-12.8%) were larger than the ~7.5% expected for sister Triatoma species; the most recent common ancestor of these T. maculata groups may date back to the late Miocene. C-heterochromatin distribution and the sex-chromosome location of 45S ribosomal DNA clusters both distinguished Roraima bugs from Orinoco and Magdalena specimens. Cytb genealogies reinforced that T. maculata is not sister to Triatoma pseudomaculata and probably represents an early (middle-late Miocene) offshoot of the 'South American Triatomini lineage'. In sum, we report extensive genetic diversity and deep phylogeographic structuring in T. maculata, suggesting that it may consist of a complex of at least three sibling taxa. These findings have implications for the systematics, population biology, and perhaps medical relevance of T. maculata sensu lato.


Assuntos
Doença de Chagas , Triatoma , Trypanosoma cruzi , Animais , Triatoma/genética , Filogenia , Doença de Chagas/veterinária , Trypanosoma cruzi/genética , DNA Mitocondrial/genética , Análise Citogenética/veterinária
13.
Community Ment Health J ; 59(7): 1330-1340, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37014585

RESUMO

Individuals with serious mental illness are vulnerable to extreme heat due to biological, social, and place-based factors. We examine the spatial correlation of prevalence of individuals treated at a community mental health center to heat vulnerability. We applied a heat vulnerability index (HVI) to the catchment of the Connecticut Mental Health Center in New Haven, Connecticut. Geocoded addresses were mapped to correlate patient prevalence with heat vulnerability of census tracts. Census tracts closer to the city center had elevated vulnerability scores. Patient prevalence was positively correlated with HVI score (Pearson's r(44) = 0.67, p < 0.01). Statistical significance persists after correction for spatial autocorrelation (modified t-test p < 0.01). The study indicates that individuals treated at this community mental health center are more likely to live in census tracts with high heat vulnerability. Heat mapping strategies can help communicate risk and target resources at the local scale.


Assuntos
Calor Extremo , Temperatura Alta , Humanos , Fatores de Risco , Connecticut/epidemiologia , Centros Comunitários de Saúde Mental
14.
J Am Chem Soc ; 144(44): 20372-20384, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36283038

RESUMO

The poor durability of Pt-based nanoparticles dispersed on carbon black is the challenge for the application of long-life polymer electrolyte fuel cells. Recent work suggests that Fe- and N-codoped carbon (Fe-N-C) might be a better support than conventional high-surface-area carbon. In this work, we find that the electrochemical surface area retention of Pt/Fe-N-C is much better than that of commercial Pt/C during potential cycling in both acidic and basic media. In situ inductively coupled plasma mass spectrometry studies indicate that the Pt dissolution rate of Pt/Fe-N-C is 3 times smaller than that of Pt/C during cycling. Density functional theory calculations further illustrate that the Fe-N-C substrate can provide strong and stable support to the Pt nanoparticles and alleviate the oxide formation by adjusting the electronic structure. The strong metal-substrate interaction, together with a lower metal dissolution rate and highly stable support, may be the reason for the significantly enhanced stability of Pt/Fe-N-C. This finding highlights the importance of carbon support selection to achieve a more durable Pt-based electrocatalyst for fuel cells.

15.
Biochem Biophys Res Commun ; 609: 156-162, 2022 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-35430419

RESUMO

The insect repellent methyl salicylate elicits excitatory responses upon interaction with CquiOR32, an odorant receptor (OR) from the southern house mosquito, Culex quinquefasciatus. By contrast, eucalyptol binds to CquiOR32 to generate electrophysiological and behavioral inhibitory responses. In an attempt to identify CquiOR32 variants displaying more robust inhibitory responses for more accurate current-voltage analysis, we sequenced 31 CquiOR32 clones. In the Xenopus oocyte recording system, CquiOR32V2/CquiOrco-expressing oocytes yielded eucalyptol-elicited outward (inhibitory) currents relatively larger than methyl salicylate-generated inward (excitatory) currents. Rescuing experiments showed that two of the amino acid substitutions in CquiOR32V2 located in a predicted transmembrane helix of the receptor are determinants of the outward/inward ratios. These findings, along with co-stimulus assays, suggest that odorant and inhibitor may bind to the same binding pocket. Current-voltage relationships obtained with standard perfusion buffer and those devoid of Na+ or Cl- indicated that both excitatory and inhibitory currents are mediated, at least in part, by cation. We then concluded that eucalyptol is an inverse agonist, which shifts the open ⇔ closed equilibrium of the receptor toward the closed conformation, thus reducing the spontaneous activity. By contrast, the binding of methyl salicylate shifts the equilibrium towards the open conformation and, consequently, leads to an increase in cation influx.


Assuntos
Culicidae , Receptores Odorantes , Animais , Eucaliptol/farmacologia , Odorantes , Receptores Odorantes/metabolismo , Olfato/fisiologia
16.
BMC Cancer ; 22(1): 645, 2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35692047

RESUMO

BACKGROUND: Given the young age of patients with CNS WHO grade 2 and 3 oligodendrogliomas and the relevant risk of neurocognitive, functional, and quality-of-life impairment with the current aggressive standard of care treatment, chemoradiation with PCV, of the tumour located in the brain optimizing care is the major challenge. METHODS: NOA-18 aims at improving qualified overall survival (qOS) for adult patients with CNS WHO grade 2 and 3 oligodendrogliomas by randomizing between standard chemoradiation with up to six six-weekly cycles with PCV and six six-weekly cycles with lomustine and temozolomide (CETEG) (n = 182 patients per group accrued over 4 years) thereby delaying radiotherapy and adding the chemoradiotherapy concept at progression after initial radiation-free chemotherapy, allowing for effective salvage treatment and delaying potentially deleterious side effects. QOS represents a new concept and is defined as OS without functional and/or cognitive and/or quality of life deterioration regardless of whether tumour progression or toxicity is the main cause. The primary objective is to show superiority of an initial CETEG treatment followed by partial brain radiotherapy (RT) plus PCV (RT-PCV) at progression over partial brain radiotherapy (RT) followed by procarbazine, lomustine, and vincristine (PCV) chemotherapy (RT-PCV) and best investigators choice (BIC) at progression for sustained qOS. An event concerning a sustained qOS is then defined as a functional and/or cognitive and/or quality of life deterioration after completion of primary therapy on two consecutive study visits with an interval of 3 months, tolerating a deviation of at most 1 month. Assessments are done with a 3-monthly MRI, assessment of the NANO scale, HRQoL, and KPS, and annual cognitive testing. Secondary objectives are evaluation and comparison of the two groups regarding secondary endpoints (short-term qOS, PFS, OS, complete and partial response rate). The trial is planned to be conducted at a minimum of 18 NOA study sites in Germany. DISCUSSION: qOS represents a new concept. The present NOA trial aims at showing the superiority of CETEG plus RT-PCV over RT-PCV plus BIC as determined at the level of OS without sustained functional deterioration for all patients with oligodendroglioma diagnosed according to the most recent WHO classification. TRIAL REGISTRATION: Clinicaltrials.gov NCT05331521 . EudraCT 2018-005027-16.


Assuntos
Neoplasias Encefálicas , Oligodendroglioma , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Humanos , Lomustina/uso terapêutico , Gradação de Tumores , Oligodendroglioma/tratamento farmacológico , Oligodendroglioma/genética , Oligodendroglioma/patologia , Procarbazina/uso terapêutico , Qualidade de Vida , Resultado do Tratamento , Vincristina/uso terapêutico
17.
Eur Cell Mater ; 43: 98-111, 2022 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-35298024

RESUMO

Knee joint osteoarthritis is a complex immunological and degenerative disease. Current treatment strategies fail to alter its progression. Mesenchymal stromal cell (MSC) therapy for osteoarthritis has been object of research for more than 30 years. The aim of MSC therapy is intended to be holistic, with regeneration of all affected knee joint structures. The paracrine effect of the MSC secretome has been shown to be central for the regenerative capacity of MSCs. Activation of local knee-joint-specific MSCs leads to an immunomodulatory, anti-catabolic, anti-apoptotic and chondrogenic stimulus. Preclinical models have demonstrated the symptom- and disease-modifying effects of MSC therapy. At the bedside, there is evidence that autologous and allogeneic MSC therapy shows significant improvement in symptom-modifying and functional outcome. Despite this, a variety of contradictory clinical outcomes are available in the literature. The effectiveness of MSC therapy is still unclear, although there have been promising results. Regarding the diversity of cell sources, isolation, culture protocols and other factors, a comparison of different studies is difficult. Clinical translation of disease-modifying effects has not yet been shown. This narrative review presents a controversial overview of the current preclinical and clinical studies on MSC therapy in knee joint osteoarthritis.


Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Osteoartrite , Humanos , Articulação do Joelho , Osteoartrite/terapia , Medicina Regenerativa/métodos
18.
BMC Med Res Methodol ; 22(1): 317, 2022 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-36513998

RESUMO

BACKGROUND: Subconcussive blast exposure during military training has been the subject of both anecdotal concerns and reports in the medical literature, but prior studies have often been small and have used inconsistent methods. METHODS: This paper presents the methodology employed in INVestigating traIning assoCiated blasT pAthology (INVICTA) to assess a wide range of aspects of brain function, including immediate and delayed recall, gait and balance, audiologic and oculomotor function, cerebral blood flow, brain electrical activity and neuroimaging and blood biomarkers. RESULTS: A number of the methods employed in INVICTA are relatively easy to reproducibly utilize, and can be completed efficiently, while other measures require greater technical expertise, take longer to complete, or may have logistical challenges. CONCLUSIONS: This presentation of methods used to assess the impact of blast exposure on the brain is intended to facilitate greater uniformity of data collection in this setting, which would enable comparison between different types of blast exposure and environmental circumstances, as well as to facilitate meta-analyses and syntheses across studies.


Assuntos
Traumatismos por Explosões , Concussão Encefálica , Militares , Humanos , Traumatismos por Explosões/patologia , Concussão Encefálica/patologia , Biomarcadores
19.
Curr Opin Ophthalmol ; 33(3): 174-187, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35266894

RESUMO

PURPOSE OF REVIEW: The application of artificial intelligence (AI) in medicine and ophthalmology has experienced exponential breakthroughs in recent years in diagnosis, prognosis, and aiding clinical decision-making. The use of digital data has also heralded the need for privacy-preserving technology to protect patient confidentiality and to guard against threats such as adversarial attacks. Hence, this review aims to outline novel AI-based systems for ophthalmology use, privacy-preserving measures, potential challenges, and future directions of each. RECENT FINDINGS: Several key AI algorithms used to improve disease detection and outcomes include: Data-driven, imagedriven, natural language processing (NLP)-driven, genomics-driven, and multimodality algorithms. However, deep learning systems are susceptible to adversarial attacks, and use of data for training models is associated with privacy concerns. Several data protection methods address these concerns in the form of blockchain technology, federated learning, and generative adversarial networks. SUMMARY: AI-applications have vast potential to meet many eyecare needs, consequently reducing burden on scarce healthcare resources. A pertinent challenge would be to maintain data privacy and confidentiality while supporting AI endeavors, where data protection methods would need to rapidly evolve with AI technology needs. Ultimately, for AI to succeed in medicine and ophthalmology, a balance would need to be found between innovation and privacy.


Assuntos
Inteligência Artificial , Oftalmologia , Humanos , Processamento de Linguagem Natural , Privacidade , Tecnologia
20.
Am J Primatol ; 84(8): e23413, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35700318

RESUMO

Robust capuchin monkeys (Sapajus spp.) are distributed widely in the Neotropics and may be able to survive in modified landscapes because of their omnivorous, opportunistic diet. The poorly known and endangered crested capuchin monkey (Sapajus robustus) is endemic to the Atlantic Forest in Bahia, Minas Gerais and Espírito Santo states, Brazil. We collected data on diet and home range for a crested capuchin group with access to forest and cultivated areas. We hypothesized that with access to cultivated exotic fruit, capuchins would use cultivated areas more for feeding during the season of fruit scarcity in the surrounding forest and have a small home range size because of higher fruit availability. Both the forest and the cultivated areas peaked in fruit availability in the wet season, with a low proportion of trees producing fruit in the dry season; cultivated areas had a higher proportion of trees in fruit compared to the forest throughout the study. While monkeys consumed exotic fruits like jackfruit and oil palm, we recorded more samples of them eating forest fruits than exotic fruits in all but 1 month, and they consumed a more diverse array of forest fruits (56 species) but only six exotic species. Home range size was relatively small compared with other studies: 120.5 ha across the year (wet season 102 ha, dry season 111.5 ha). Natural and human-intensified fruit sources in a protected area without hunting may have allowed monkeys to maintain a smaller home range size. The group composition changed during the study; this also likely influenced home range use. Studies focused on robust capuchin groups that utilize agricultural or cultivated foods may underestimate home range needs for groups without access to human-intensified food sources. Studying crested capuchin ecology in additional locations will be important for establishing a sound species conservation program.


Assuntos
Cebinae , Cebus , Animais , Brasil , Dieta/veterinária , Comportamento Alimentar , Florestas , Frutas , Comportamento de Retorno ao Território Vital , Humanos
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