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1.
Nature ; 619(7971): 724-732, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37438522

RESUMO

The presence and distribution of preserved organic matter on the surface of Mars can provide key information about the Martian carbon cycle and the potential of the planet to host life throughout its history. Several types of organic molecules have been previously detected in Martian meteorites1 and at Gale crater, Mars2-4. Evaluating the diversity and detectability of organic matter elsewhere on Mars is important for understanding the extent and diversity of Martian surface processes and the potential availability of carbon sources1,5,6. Here we report the detection of Raman and fluorescence spectra consistent with several species of aromatic organic molecules in the Máaz and Séítah formations within the Crater Floor sequences of Jezero crater, Mars. We report specific fluorescence-mineral associations consistent with many classes of organic molecules occurring in different spatial patterns within these compositionally distinct formations, potentially indicating different fates of carbon across environments. Our findings suggest there may be a diversity of aromatic molecules prevalent on the Martian surface, and these materials persist despite exposure to surface conditions. These potential organic molecules are largely found within minerals linked to aqueous processes, indicating that these processes may have had a key role in organic synthesis, transport or preservation.

2.
Cell ; 145(7): 1088-101, 2011 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-21703451

RESUMO

INAD is a scaffolding protein that regulates signaling in Drosophila photoreceptors. One of its PDZ domains, PDZ5, cycles between reduced and oxidized forms in response to light, but it is unclear how light affects its redox potential. Through biochemical and structural studies, we show that the redox potential of PDZ5 is allosterically regulated by its interaction with another INAD domain, PDZ4. Whereas isolated PDZ5 is stable in the oxidized state, formation of a PDZ45 "supramodule" locks PDZ5 in the reduced state by raising the redox potential of its Cys606/Cys645 disulfide bond by ∼330 mV. Acidification, potentially mediated via light and PLCß-mediated hydrolysis of PIP(2), disrupts the interaction between PDZ4 and PDZ5, leading to PDZ5 oxidation and dissociation from the TRP Ca(2+) channel, a key component of fly visual signaling. These results show that scaffolding proteins can actively modulate the intrinsic redox potentials of their disulfide bonds to exert regulatory roles in signaling.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Proteínas do Olho/metabolismo , Sequência de Aminoácidos , Animais , Proteínas de Drosophila/química , Olho/metabolismo , Proteínas do Olho/química , Modelos Moleculares , Oxirredução , Domínios PDZ , Células Fotorreceptoras de Invertebrados/metabolismo , Transdução de Sinais
3.
Proc Natl Acad Sci U S A ; 119(12): e2109717119, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35298337

RESUMO

SignificanceTo move efficiently, animals must continuously work out their x,y,z positions with respect to real-world objects, and many animals have a pair of eyes to achieve this. How photoreceptors actively sample the eyes' optical image disparity is not understood because this fundamental information-limiting step has not been investigated in vivo over the eyes' whole sampling matrix. This integrative multiscale study will advance our current understanding of stereopsis from static image disparity comparison to a morphodynamic active sampling theory. It shows how photomechanical photoreceptor microsaccades enable Drosophila superresolution three-dimensional vision and proposes neural computations for accurately predicting these flies' depth-perception dynamics, limits, and visual behaviors.


Assuntos
Percepção de Profundidade , Drosophila , Animais , Olho , Disparidade Visual , Visão Ocular
4.
J Infect Dis ; 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39189818

RESUMO

BACKGROUND: Mycobacterium abscessus complex (MABC), an opportunistic nontuberculous mycobacteria (NTM), can lead to poor clinical outcomes in pulmonary infections. Conflicting data exist on person-to-person transmission of MABC within and across healthcare facilities. To investigate further, a comprehensive retrospective study across five healthcare institutions on the Island of Montréal was undertaken. METHODS: We analyzed the genomes of 221 MABC isolates obtained from 115 individuals (2010-2018) to identify possible links. Genetic similarity, defined as ≤25 single-nucleotide polymorphisms (SNPs), was investigated through a blinded epidemiological inquiry. RESULTS: Bioinformatics analyses identified 28 sequence types (STs), including globally observed dominant circulating clones (DCCs). Further analysis revealed 210 isolate pairs within the SNP threshold. Among these pairs, there was one possible lab contamination where isolates from different patients processed in the same lab differed by only 2 SNPs. There were 37 isolate pairs from patients who had provided specimens from the same hospital; however, epidemiological analysis found no evidence of healthcare-associated person-to-person transmission between these patients. Additionally, pan-genome analysis showed higher discriminatory power than core genome analysis for examining genomic similarity. CONCLUSIONS: Genomics alone is insufficient to establish MABC transmission, particularly considering the genetic similarity and wide distribution of DCCs, although pan-genome analysis has the potential to add further insight. Our findings indicate that MABC infections in Montréal are unlikely attributable to healthcare-associated person-to-person transmission.

5.
Dev Biol ; 498: 35-48, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36933633

RESUMO

Fibroblasts play an important role in maintaining tissue integrity by secreting components of the extracellular matrix and initiating response to injury. Although the function of fibroblasts has been extensively studied in adults, the embryonic origin and diversification of different fibroblast subtypes during development remain largely unexplored. Using zebrafish as a model, we show that the sclerotome, a sub-compartment of the somite, is the embryonic source of multiple fibroblast subtypes including tenocytes (tendon fibroblasts), blood vessel associated fibroblasts, fin mesenchymal cells, and interstitial fibroblasts. High-resolution imaging shows that different fibroblast subtypes occupy unique anatomical locations with distinct morphologies. Long-term Cre-mediated lineage tracing reveals that the sclerotome also contributes to cells closely associated with the axial skeleton. Ablation of sclerotome progenitors results in extensive skeletal defects. Using photoconversion-based cell lineage analysis, we find that sclerotome progenitors at different dorsal-ventral and anterior-posterior positions display distinct differentiation potentials. Single-cell clonal analysis combined with in vivo imaging suggests that the sclerotome mostly contains unipotent and bipotent progenitors prior to cell migration, and the fate of their daughter cells is biased by their migration paths and relative positions. Together, our work demonstrates that the sclerotome is the embryonic source of trunk fibroblasts as well as the axial skeleton, and local signals likely contribute to the diversification of distinct fibroblast subtypes.


Assuntos
Somitos , Peixe-Zebra , Animais , Diferenciação Celular , Linhagem da Célula , Fibroblastos
6.
BMC Genomics ; 25(1): 541, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38822259

RESUMO

BACKGROUND: Flight can drastically enhance dispersal capacity and is a key trait defining the potential of exotic insect species to spread and invade new habitats. The phytophagous European spongy moths (ESM, Lymantria dispar dispar) and Asian spongy moths (ASM; a multi-species group represented here by L. d. asiatica and L. d. japonica), are globally invasive species that vary in adult female flight capability-female ASM are typically flight capable, whereas female ESM are typically flightless. Genetic markers of flight capability would supply a powerful tool for flight profiling of these species at any intercepted life stage. To assess the functional complexity of spongy moth flight and to identify potential markers of flight capability, we used multiple genetic approaches aimed at capturing complementary signals of putative flight-relevant genetic divergence between ESM and ASM: reduced representation genome-wide association studies, whole genome sequence comparisons, and developmental transcriptomics. We then judged the candidacy of flight-associated genes through functional analyses aimed at addressing the proximate demands of flight and salient features of the ecological context of spongy moth flight evolution. RESULTS: Candidate gene sets were typically non-overlapping across different genetic approaches, with only nine gene annotations shared between any pair of approaches. We detected an array of flight-relevant functional themes across gene sets that collectively suggest divergence in flight capability between European and Asian spongy moth lineages has coincided with evolutionary differentiation in multiple aspects of flight development, execution, and surrounding life history. Overall, our results indicate that spongy moth flight evolution has shaped or been influenced by a large and functionally broad network of traits. CONCLUSIONS: Our study identified a suite of flight-associated genes in spongy moths suited to exploration of the genetic architecture and evolution of flight, or validation for flight profiling purposes. This work illustrates how complementary genetic approaches combined with phenotypically targeted functional analyses can help to characterize genetically complex traits.


Assuntos
Voo Animal , Espécies Introduzidas , Mariposas , Animais , Mariposas/genética , Mariposas/fisiologia , Feminino , Estudo de Associação Genômica Ampla , Fenótipo , Transcriptoma , Complexo de Mariposas do Gênero Lymantria
7.
Drug Metab Rev ; 56(2): 164-174, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38655747

RESUMO

Due to legal, political, and cultural changes, the use of cannabis has rapidly increased in recent years. Research has demonstrated that the cannabinoids cannabidiol (CBD) and Δ9-tetrahydrocannabinol (THC) inhibit and induce cytochrome P450 (CYP450) enzymes. The objective of this review is to evaluate the effect of CBD and THC on the activity of CYP450 enzymes and the implications for drug-drug interactions (DDIs) with psychotropic agents that are CYP substrates. A systematic search was conducted using PubMed, Scopus, Scientific Electronic Library Online (SciELO) and PsychINFO. Search terms included 'cannabidiol', 'tetrahydrocannabinol', and 'cytochrome P450'. A total of seven studies evaluating the interaction of THC and CBD with CYP450 enzymes and psychotropic drugs were included. Both preclinical and clinical studies were included. Results from the included studies indicate that both CBD and THC inhibit several CYP450 enzymes including, but not limited to, CYP1A2, CYP3C19, and CYP2B6. While there are a few known CYP450 enzymes that are induced by THC and CBD, the induction of CYP450 enzymes is an understudied area of research and lacks clinical data. The inhibitory effects observed by CBD and THC on CYP450 enzymes vary in magnitude and may decrease the metabolism of psychotropic agents, cause changes in plasma levels of psychotropic medications, and increase adverse effects. Our findings clearly present interactions between THC and CBD and several CYP450 enzymes, providing clinicians evidence of a high risk of DDIs for patients who consume both cannabis and psychotropic medication. However, more clinical research is necessary before results are applied to clinical settings.


Assuntos
Canabidiol , Sistema Enzimático do Citocromo P-450 , Dronabinol , Interações Medicamentosas , Animais , Humanos , Canabidiol/farmacologia , Inibidores das Enzimas do Citocromo P-450/farmacologia , Sistema Enzimático do Citocromo P-450/metabolismo , Dronabinol/farmacologia , Psicotrópicos/farmacologia
8.
Phys Rev Lett ; 133(5): 053401, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39159118

RESUMO

We demonstrate subrecoil Sisyphus cooling using the long-lived ^{3}P_{0} clock state in alkaline-earth-like ytterbium. A 1388-nm optical standing wave nearly resonant with the ^{3}P_{0}→^{3}D_{1} transition creates a spatially periodic light shift of the ^{3}P_{0} clock state. Following excitation on the ultranarrow clock transition, we observe Sisyphus cooling in this potential, as the light shift is correlated with excitation to ^{3}D_{1} and subsequent spontaneous decay to the ^{1}S_{0} ground state. We observe that cooling enhances the loading efficiency of atoms into a 759-nm magic-wavelength one-dimensional (1D) optical lattice, as compared to standard Doppler cooling on the ^{1}S_{0}→^{3}P_{1} transition. Sisyphus cooling yields temperatures below 200 nK in the weakly confined, transverse dimensions of the 1D optical lattice. These lower temperatures improve optical lattice clocks by facilitating the use of shallow lattices with reduced light shifts while retaining large atom numbers to reduce the quantum projection noise. This Sisyphus cooling can be pulsed or continuous and is applicable to a range of quantum metrology applications.

9.
Cell ; 139(2): 246-64, 2009 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-19837030

RESUMO

Seeing begins in the photoreceptors, where light is absorbed and signaled to the nervous system. Throughout the animal kingdom, photoreceptors are diverse in design and purpose. Nonetheless, phototransduction-the mechanism by which absorbed photons are converted into an electrical response-is highly conserved and based almost exclusively on a single class of photoproteins, the opsins. In this Review, we survey the G protein-coupled signaling cascades downstream from opsins in photoreceptors across vertebrate and invertebrate species, noting their similarities as well as differences.


Assuntos
Transdução de Sinal Luminoso , Receptores Acoplados a Proteínas G/metabolismo , Animais , Humanos , Células Fotorreceptoras de Invertebrados/metabolismo , Células Fotorreceptoras de Vertebrados
10.
Nature ; 554(7691): 183-188, 2018 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-29364874

RESUMO

The fastest and most manoeuvrable terrestrial animals are found in savannah habitats, where predators chase and capture running prey. Hunt outcome and success rate are critical to survival, so both predator and prey should evolve to be faster and/or more manoeuvrable. Here we compare locomotor characteristics in two pursuit predator-prey pairs, lion-zebra and cheetah-impala, in their natural savannah habitat in Botswana. We show that although cheetahs and impalas were universally more athletic than lions and zebras in terms of speed, acceleration and turning, within each predator-prey pair, the predators had 20% higher muscle fibre power than prey, 37% greater acceleration and 72% greater deceleration capacity than their prey. We simulated hunt dynamics with these data and showed that hunts at lower speeds enable prey to use their maximum manoeuvring capacity and favour prey survival, and that the predator needs to be more athletic than its prey to sustain a viable success rate.


Assuntos
Acinonyx/psicologia , Equidae/fisiologia , Leões/fisiologia , Comportamento Predatório/fisiologia , Ruminantes/fisiologia , Aceleração , Animais , Botsuana , Feminino , Masculino , Músculo Esquelético/fisiologia , Corrida/fisiologia
11.
Clin Exp Nephrol ; 28(6): 496-504, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38402504

RESUMO

A critical degree of podocyte depletion causes glomerulosclerosis, and persistent podocyte loss in glomerular diseases drives the progression to end-stage kidney disease. The extent of podocyte injury at a point in time can be histologically assessed by measuring podocyte number, size, and density ("Biopsy podometrics"). However, repeated invasive renal biopsies are associated with increased risk and cost. A noninvasive method for assessing podocyte injury and depletion is required. Albuminuria and proteinuria do not always correlate with disease activity. Podocytes are located on the urinary space side of the glomerular basement membrane, and as they undergo stress or detach, their products can be identified in urine. This raises the possibility that urinary podocyte products can serve as clinically useful markers for monitoring glomerular disease activity and progression ("Urinary podometrics"). We previously reported that urinary sediment podocyte mRNA reflects disease activity in both animal models and human glomerular diseases. This includes diabetes and hypertension which together account for 60% of new-onset dialysis induction patients. Improving approaches to preventing progression is an urgent priority for the renal community. Sufficient evidence now exists to indicate that monitoring urinary podocyte markers could serve as a useful adjunctive strategy for determining the level of current disease activity and response to therapy in progressive glomerular diseases.


Assuntos
Biomarcadores , Podócitos , Podócitos/patologia , Humanos , Biomarcadores/urina , Animais , Insuficiência Renal Crônica/urina , Insuficiência Renal Crônica/patologia , Insuficiência Renal Crônica/diagnóstico , Progressão da Doença , Proteinúria/urina , Proteinúria/etiologia , Injúria Renal Aguda/urina , Injúria Renal Aguda/patologia , Injúria Renal Aguda/terapia , Injúria Renal Aguda/etiologia
12.
Proc Natl Acad Sci U S A ; 118(33)2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34373328

RESUMO

During the last interglacial (LIG) period, global mean sea level (GMSL) was higher than at present, likely driven by greater high-latitude insolation. Past sea-level estimates require elevation measurements and age determination of marine sediments that formed at or near sea level, and those elevations must be corrected for glacial isostatic adjustment (GIA). However, this GIA correction is subject to uncertainties in the GIA model inputs, namely, Earth's rheology and past ice history, which reduces precision and accuracy in estimates of past GMSL. To better constrain the GIA process, we compare our data and existing LIG sea-level data across the Bahamian archipelago with a suite of 576 GIA model predictions. We calculated weights for each GIA model based on how well the model fits spatial trends in the regional sea-level data and then used the weighted GIA corrections to revise estimates of GMSL during the LIG. During the LIG, we find a 95% probability that global sea level peaked at least 1.2 m higher than today, and it is very unlikely (5% probability) to have exceeded 5.3 m. Estimates increase by up to 30% (decrease by up to 20%) for portions of melt that originate from the Greenland ice sheet (West Antarctic ice sheet). Altogether, this work suggests that LIG GMSL may be lower than previously assumed.

13.
Clin J Sport Med ; 34(1): 30-37, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37432349

RESUMO

OBJECTIVE: To determine whether alcohol use leads to prolonged clinical recovery or increased severity of concussion symptoms in National Collegiate Athletic Association (NCAA) athletes. DESIGN: Prospective observational study. SETTING: Clinical institutions. PARTICIPANTS: Athletes from the NCAA Concussion Assessment Research and Education consortium who sustained a concussion from 2014 to 2021. INTERVENTIONS: Athletes were divided into 2 groups, those reporting alcohol use postinjury and those reporting no alcohol use postinjury. MAIN OUTCOME MEASURES: Symptom recovery was evaluated as time (in days) from injury to clearance to return to unrestricted play (days until URTP). Severity of concussion symptoms was assessed using the Standardized Sport Concussion Assessment Tool (SCAT3) symptom severity, headache severity, difficulty concentrating, and difficulty remembering scores. These scores were taken a median of 6.6 [interquartile range (IQR) = 4.0-10] and 6 (IQR = 4.0-9.0) days after injury for those who did and did not consume alcohol postinjury respectively and compared with baseline SCAT3 scores. RESULTS: Four hundred eighty four athletes from the data set had complete data for exposure and outcome. The adjusted mean number of days until URTP for athletes reporting alcohol use postinjury [23.3; 95% confidence interval (CI), 20.0-27.2; days] was incidence rate ratio (IRR) 1.32 (95% CI, 1.12-1.55; P < 0.001) times higher than for athletes who reported no alcohol use postinjury [17.7 (95% CI, 16.1-19.3) days]. Postinjury alcohol was not associated with severity of concussion symptoms ( P 's < 0.05). CONCLUSION: Self-reported postinjury alcohol use is associated with prolonged recovery but not severity of concussion symptoms in collegiate athletes. This may inform future clinical recommendations regarding alcohol consumption after concussion.


Assuntos
Traumatismos em Atletas , Concussão Encefálica , Esportes , Humanos , Traumatismos em Atletas/epidemiologia , Concussão Encefálica/diagnóstico , Concussão Encefálica/etiologia , Atletas , Consumo de Bebidas Alcoólicas , Testes Neuropsicológicos
14.
J Acoust Soc Am ; 155(1): 420-435, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38240669

RESUMO

The Perseverance rover is carrying out an original acoustic experiment on Mars: the SuperCam microphone records the spherical acoustic waves generated by laser sparks at distances from 2 m to more than 8 m. These N-shaped acoustic waves scatter from the multiple local heterogeneities of the turbulent atmosphere. Therefore, large and random fluctuations of sound travel time and intensity develop as the waves cross the medium. The variances of the travel times and the scintillation index (normalized variance of the sound intensity) are studied within the mathematical formalism of the propagation of spherical acoustic waves through thermal turbulence to infer statistical properties of the Mars atmospheric temperature fluctuation field. The comparison with the theory is made by simplifying assumptions that do not include wind fluctuations and diffraction effects. Two Earth years (about one Martian year) of observations acquired during the maximum convective period (10:00-14:00 Mars local time) show a good agreement between the dataset and the formalism: the travel time variance diverges from the linear Chernov solution exactly where the density of occurrence of the first caustic reaches its maximum. Moreover, on average, waves travel faster than the mean speed of sound due to a fast path effect, which is also observed on Earth. To account for the distribution of turbulent eddies, several power spectra are tested and the best match to observation is obtained with a generalized von Karman spectrum with a shallower slope than the Kolmogorov cascade, ϕ(k)∝(1+k2L2)-4/3. It is associated with an outer scale of turbulence, L, of 11 cm at 2 m above the surface and a standard deviation of 6 K over 9 s for the temperature. These near-surface atmospheric properties are consistent with a weak to moderate wave scattering regime around noon with little saturation. Overall, this study presents an innovative and promising methodology to probe the near-surface atmospheric turbulence on Mars.

15.
Cleft Palate Craniofac J ; : 10556656241266464, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39043360

RESUMO

OBJECTIVE: To explore the role of multidisciplinary velopharyngeal dysfunction (VPD) assessment in diagnosing 22q11.2 deletion syndrome (22q) in children. DESIGN: Retrospective cohort study. SETTING: Multidisciplinary VPD clinic at a tertiary pediatric hospital. PATIENTS, PARTICIPANTS: Seventy-five children with genetically confirmed 22q evaluated at the VPD clinic between February 2007 and February 2023, including both previously diagnosed patients and those newly diagnosed as a result of VPD evaluation. INTERVENTIONS: Comprehensive review of medical records, utilizing ICD-10 codes and an institutional tool for keyword searches, to identify patients and collect data on clinical variables and outcomes. MAIN OUTCOME MEASURES: Characteristics of children with 22q, pathways to diagnosis, and clinical presentations that led to genetic testing for 22q. RESULTS: Of the 75 children, 9 were newly diagnosed with 22q following VPD evaluation. Non-cleft VPI was a significant indicator for 22q in children not previously diagnosed, occurring in 100% of newly diagnosed cases compared to 52% of cases with existing 22q diagnosis (P = .008). Additional clinical findings leading to diagnosis included congenital heart disease, craniofacial abnormalities, and developmental delays. CONCLUSIONS: VPD evaluations, particularly the presence of non-cleft VPI, play a crucial role in identifying undiagnosed cases of 22q. This underscores the need for clinicians, including plastic surgeons, otolaryngologists, and speech-language pathologists, to maintain a high degree of suspicion for 22q in children presenting with VPI without a clear etiology. Multidisciplinary approaches are essential for early diagnosis and management of this complex condition.

16.
Mil Psychol ; : 1-14, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38975902

RESUMO

The purpose of the current paper is to explore the influence of the perceived trustworthiness factors of ability, benevolence and integrity on general and specific trust across supervisors, subordinates and peers with the same focal referent. This study used a 360-degree approach to examine how positional power asymmetries influence the relationship between trustworthiness and trust for a general and situation-specific referent. Data were obtained from military supervisors (N = 200), peers (N = 123), and subordinates (N = 85). Measures of trustworthiness and trust of a common military officer were obtained. Supervisors and subordinates differed in their relative weighting of trustworthiness factors (i.e. ability, benevolence, and integrity) when evaluating general and specific trust. Peers evidenced no difference in the relative weighting of trustworthiness factors. The relationship between benevolence and specific trust was stronger for subordinates than for supervisors. One implication of our findings is that trust can develop differently in bottom-up versus top-down organizational relationships. This study provides evidence that supervisors and subordinates emphasize different aspects of trustworthiness when evaluating their trust of a focal officer, and this process was different for general versus specific trust referents. The study also extends previous research by replicating previous findings across raters.

17.
J Infect Dis ; 227(Suppl 1): S30-S37, 2023 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-36930636

RESUMO

In this fifth decade of the human immunodeficiency virus (HIV) epidemic, central nervous system (CNS) complications including cognitive impairment and mental health remain a burden for people with HIV (PWH) on antiretroviral therapy. Despite the persistence of these complications, which often co-occur, the underlying pathophysiology remains elusive and consequently treatments remain limited. To continue to grow our understanding of the underlying mechanisms of CNS complications among PWH, there is a need to reexamine our current approaches, which are now more than 2 decades old. At the 2021 National Institutes of Health-sponsored meeting on Biotypes of CNS Complications in PWH, the Neurobehavioral Working Group addressed the following: (1) challenges inherent to determining CNS complications; (2) heterogeneity in CNS complications; and (3) problems and solutions for examining integrated biotypes. The review below provides a summary of the main points presented and discussed by the Neurobehavioral Working Group at the meeting.


Assuntos
Infecções por HIV , HIV , Humanos , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Sistema Nervoso Central
18.
Am J Physiol Cell Physiol ; 325(1): C172-C185, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37212546

RESUMO

Specific force (SF) has been shown to be reduced in some but not all studies of human aging using chemically skinned single muscle fibers. This may be due, in part, not only to the health status/physical activity levels of different older cohorts, but also from methodological differences in studying skinned fibers. The aim of the present study was to compare SF in fibers from older hip fracture patients (HFP), healthy master cyclists (MC), and healthy nontrained young adults (YA) using two different activating solutions. Quadriceps muscle samples and 316 fibers were obtained from HFPs (74.6 ± 4 years, n = 5), MCs (74.8 ± 1, n = 5), and YA (25.5 ± 2, n = 6). Fibers were activated (pCa 4.5, 15°C) in solutions containing either 60 mM N-tris(hydroxymethyl)methyl-2-aminoethanesulfonic acid pH buffer (TES) or 20 mM imidazole. SF was determined by normalizing force to fiber cross-sectional area (CSA) assuming either an elliptical or circular shape and to fiber myosin heavy chain content. Activation in TES resulted in significantly higher MHC-I SF in all groups and YA MHC-IIA fibers, irrespective of normalization method. Although there were no differences in SF between the participant groups, the ratio of SF between the TES and imidazole solutions was lower in HFPs compared with YAs (MHC-I P < 0.05; MHC-IIA P = 0.055). Activating solution composition, as opposed to donor characteristics, had a more notable effect on single fiber SF. However, this two-solution approach revealed an age-related difference in sensitivity in HFPs, which was not shown in MCs. This suggests further novel approaches may be required to probe age/activity-related differences in muscle contractile quality.NEW & NOTEWORTHY Whether specific force (SF) decreases with advancing age in human single skeletal muscle fibers is uncertain. Equivocal published findings may be due to the different physical activity levels of the elderly cohorts studied and/or different chemical solutions used to measure force. We compared single fiber SF between young adults, elderly cyclists, and hip fracture patients (HFP) using two solutions. The solution used significantly affected force and revealed a difference in sensitivity of HFP muscle fibers.


Assuntos
Contração Muscular , Fibras Musculares Esqueléticas , Adulto Jovem , Humanos , Idoso , Contração Muscular/fisiologia , Cadeias Pesadas de Miosina , Envelhecimento , Músculo Quadríceps , Músculo Esquelético/fisiologia
19.
Mol Microbiol ; 117(4): 770-789, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34942035

RESUMO

Salmonella is a major foodborne pathogen and is responsible for a range of diseases. Not all Salmonella contributes to severe health outcomes as there is a large degree of genetic heterogeneity among the 2,600 serovars within the genus. This variability across Salmonella serovars is linked to numerous genetic elements that dictate virulence. While several genetic elements encode virulence factors with well-documented contributions to pathogenesis, many genetic elements implicated in Salmonella virulence remain uncharacterized. Many pathogens encode a family of E3 ubiquitin ligases that are delivered into the cells that they infect using a Type 3 Secretion System (T3SS). These effectors, known as NEL-domain E3s, were first characterized in Salmonella. Most Salmonella encodes the NEL-effectors sspH2 and slrP, whereas only a subset of Salmonella encodes sspH1. SspH1 has been shown to ubiquitinate the mammalian protein kinase PKN1, which has been reported to negatively regulate the pro-survival program Akt. We discovered that SspH1 mediates the degradation of PKN1 during infection of a macrophage cell line but that this degradation does not impact Akt signaling. Genomic analysis of a large collection of Salmonella genomes identified a putative new gene, sspH3, with homology to sspH1. SspH3 is a novel NEL-domain effector.


Assuntos
Proteínas de Bactérias , Proteínas Proto-Oncogênicas c-akt , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Mamíferos/metabolismo , Salmonella/genética , Salmonella/metabolismo , Sistemas de Secreção Tipo III , Ubiquitina-Proteína Ligases/metabolismo
20.
Ann Surg ; 277(1): 50-56, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33491983

RESUMO

OBJECTIVE: To assess the degree of psychological impact among surgical providers during the COVID-19 pandemic. SUMMARY OF BACKGROUND DATA: The COVID-19 pandemic has extensively impacted global healthcare systems. We hypothesized that the degree of psychological impact would be higher for surgical providers deployed for COVID-19 work, certain surgical specialties, and for those who knew of someone diagnosed with, or who died, of COVID-19. METHODS: We conducted a global web-based survey to investigate the psychological impact of COVID-19. The primary outcomes were the depression anxiety stress scale-21 and Impact of Event Scale-Revised scores. RESULTS: A total of 4283 participants from 101 countries responded. 32.8%, 30.8%, 25.9%, and 24.0% screened positive for depression, anxiety, stress, and PTSD respectively. Respondents who knew someone who died of COVID-19 were more likely to screen positive for depression, anxiety, stress, and PTSD (OR 1.3, 1.6, 1.4, 1.7 respectively, all P < 0.05). Respondents who knew of someone diagnosed with COVID-19 were more likely to screen positive for depression, stress, and PTSD (OR 1.2, 1.2, and 1.3 respectively, all P < 0.05). Surgical specialties that operated in the head and neck region had higher psychological distress among its surgeons. Deployment for COVID- 19-related work was not associated with increased psychological distress. CONCLUSIONS: The COVID-19 pandemic may have a mental health legacy outlasting its course. The long-term impact of this ongoing traumatic event underscores the importance of longitudinal mental health care for healthcare personnel, with particular attention to those who know of someone diagnosed with, or who died of COVID-19.


Assuntos
COVID-19 , Cirurgiões , Humanos , Saúde Mental , SARS-CoV-2 , Pandemias , Depressão/psicologia , Ansiedade/psicologia , Pessoal de Saúde/psicologia , Inquéritos e Questionários , Estresse Psicológico/psicologia
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