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1.
Nat Chem Biol ; 20(7): 906-915, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38831036

RESUMO

Natural photosystems couple light harvesting to charge separation using a 'special pair' of chlorophyll molecules that accepts excitation energy from the antenna and initiates an electron-transfer cascade. To investigate the photophysics of special pairs independently of the complexities of native photosynthetic proteins, and as a first step toward creating synthetic photosystems for new energy conversion technologies, we designed C2-symmetric proteins that hold two chlorophyll molecules in closely juxtaposed arrangements. X-ray crystallography confirmed that one designed protein binds two chlorophylls in the same orientation as native special pairs, whereas a second designed protein positions them in a previously unseen geometry. Spectroscopy revealed that the chlorophylls are excitonically coupled, and fluorescence lifetime imaging demonstrated energy transfer. The cryo-electron microscopy structure of a designed 24-chlorophyll octahedral nanocage with a special pair on each edge closely matched the design model. The results suggest that the de novo design of artificial photosynthetic systems is within reach of current computational methods.


Assuntos
Clorofila , Clorofila/química , Clorofila/metabolismo , Cristalografia por Raios X , Modelos Moleculares , Fotossíntese , Transferência de Energia , Microscopia Crioeletrônica , Conformação Proteica , Complexos de Proteínas Captadores de Luz/química , Complexos de Proteínas Captadores de Luz/metabolismo
2.
Plant Cell Environ ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38924477

RESUMO

Predicting soil water status remotely is appealing due to its low cost and large-scale application. During drought, plants can disconnect from the soil, causing disequilibrium between soil and plant water potentials at pre-dawn. The impact of this disequilibrium on plant drought response and recovery is not well understood, potentially complicating soil water status predictions from plant spectral reflectance. This study aimed to quantify drought-induced disequilibrium, evaluate plant responses and recovery, and determine the potential for predicting soil water status from plant spectral reflectance. Two species were tested: sweet corn (Zea mays), which disconnected from the soil during intense drought, and peanut (Arachis hypogaea), which did not. Sweet corn's hydraulic disconnection led to an extended 'hydrated' phase, but its recovery was slower than peanut's, which remained connected to the soil even at lower water potentials (-5 MPa). Leaf hyperspectral reflectance successfully predicted the soil water status of peanut consistently, but only until disequilibrium occurred in sweet corn. Our results reveal different hydraulic strategies for plants coping with extreme drought and provide the first example of using spectral reflectance to quantify rhizosphere water status, emphasizing the need for species-specific considerations in soil water status predictions from canopy reflectance.

4.
Front Immunol ; 15: 1371706, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38650935

RESUMO

Pulmonary hypertension (PH) pathogenesis is driven by inflammatory and metabolic derangements as well as glycolytic reprogramming. Induction of both interleukin 6 (IL6) and transglutaminase 2 (TG2) expression participates in human and experimental cardiovascular diseases. However, little is known about the role of TG2 in these pathologic processes. The current study aimed to investigate the molecular interactions between TG2 and IL6 in mediation of tissue remodeling in PH. A lung-specific IL6 over-expressing transgenic mouse strain showed elevated right ventricular (RV) systolic pressure as well as increased wet and dry tissue weights and tissue fibrosis in both lungs and RVs compared to age-matched wild-type littermates. In addition, IL6 over-expression induced the glycolytic and fibrogenic markers, hypoxia-inducible factor 1α, pyruvate kinase M2 (PKM2), and TG2. Consistent with these findings, IL6 induced the expression of both glycolytic and pro-fibrogenic markers in cultured lung fibroblasts. IL6 also induced TG2 activation and the accumulation of TG2 in the extracellular matrix. Pharmacologic inhibition of the glycolytic enzyme, PKM2 significantly attenuated IL6-induced TG2 activity and fibrogenesis. Thus, we conclude that IL6-induced TG2 activity and cardiopulmonary remodeling associated with tissue fibrosis are under regulatory control of the glycolytic enzyme, PKM2.


Assuntos
Fibroblastos , Proteínas de Ligação ao GTP , Hipertensão Pulmonar , Interleucina-6 , Pulmão , Camundongos Transgênicos , Proteína 2 Glutamina gama-Glutamiltransferase , Piruvato Quinase , Transglutaminases , Animais , Humanos , Camundongos , Modelos Animais de Doenças , Fibroblastos/metabolismo , Fibrose , Proteínas de Ligação ao GTP/metabolismo , Proteínas de Ligação ao GTP/genética , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/patologia , Hipertensão Pulmonar/etiologia , Interleucina-6/metabolismo , Pulmão/patologia , Pulmão/imunologia , Pulmão/metabolismo , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/patologia , Piruvato Quinase/metabolismo , Piruvato Quinase/genética , Transglutaminases/metabolismo , Transglutaminases/genética
5.
J Infect Public Health ; 17(6): 1007-1012, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38636311

RESUMO

BACKGROUND: When it comes to pandemic response, preparation can be the key. Between 2020 and 2024, the fast-paced development of COVID-19-often compounded by pubic policies' failures to reflect the latest reality and the public's divergent reactions to the pandemic and the policies-means that society should prepare for exit strategies that can reflect the reality of the pandemic and the interests of the people. Yet oftentimes societies only have one exit strategy with limited scope. This paper investigates the dangers of having only one pandemic exit strategy for pandemics like COVID-19. METHODS: Analyses were based on a review of the literature on COVID-19 exit strategies and our own research. The PubMed literature search focused on two concepts-"COVID-19″ and "exit strategy"-and was limited to peer-reviewed papers published between 2020 and 2024 in English. RESULTS: A total of 31 articles were included in the final review. Analyses showed that existing studies on COVID-19 exit strategies often focused on using the modelling method to gauge one exit strategy. Exit strategies were often discussed in the context of implementing, easing, or lifting specific pharmaceutical or non-pharmaceutical interventions. Staged and country-wide coordinated exit strategies were also discussed in the literature, both of which were often deemed as comparatively rigorous options compared to single or stand-alone exit strategies. Drawing on the overall development of COVID-19 and our own research, we presented and discussed the importance of having multiple exit strategies that are considerate of all possible pandemic trajectories, diverse interests of the public, and the communication challenges officials might face in introducing or implementing pandemic policies. CONCLUSION: This paper underscored the importance of having multiple exit strategies for societies to prepare for pandemics. The insights of this study can help inform health policies so that they can more comprehensively and compassionately protect the needs and wants of the "public" in public health, particularly in grave times like COVID-19.


Assuntos
COVID-19 , Pandemias , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Pandemias/prevenção & controle , SARS-CoV-2 , Saúde Pública , Política de Saúde , Controle de Doenças Transmissíveis/métodos
6.
Artigo em Inglês | MEDLINE | ID: mdl-38640067

RESUMO

We critically evaluate the current status of portable mass spectrometry (pMS), particularly where this aligns with ambient ionization. Assessing the field of pMS can be quite subjective, especially in relation to the portable aspects of design, deployment, and operation. In this review, we discuss what it means to be portable and introduce a set of criteria by which pMS and ambient ionization sources can be assessed. Moreover, we consider the recent literature in terms of the most popular and significant advances in portable instrumentation for ambient ionization and miniature mass spectrometers. Finally, emerging trends and exciting future prospects are discussed and some recommendations are offered.

7.
Ann Burns Fire Disasters ; 37(1): 64-78, 2024 Mar.
Artigo em Francês | MEDLINE | ID: mdl-38680834

RESUMO

The acute management of deep burns to the dorsum of the hand and fingers represents a challenge for the reconstructive surgeon. The exposure of osteo-tendinous structures often requires flap coverage, in a context where loco-regional or free flaps are not always feasible. The aims of reconstruction are to preserve a maximum of digital length, provide supple tissue, obtain protective sensitivity, and achieve a functional hand at 1 year. We report here on a series of 8 deep burns to the dorsum of the hand. Six hands were covered by Colson abdominal flap-graft and two by pedicled inguinal flap. Four out of 6 patients were reviewed in consultation, 1 patient was lost to follow-up, and 1 patient died. Clinical evaluation was performed by a surgeon other than the operator. Functional results are highly variable. Coverage time varies according to lesion depth and patient severity. Flap weaning took place at an average of 30 days. DASH scores ranged from 17.5 to 93/100, with average to poor total active motion (TAM) scores. The aesthetic result was satisfactory, with a Vancouver score of 4.5/13 on average, and an overall patient opinion of 3.75/10 on the POSAS scale. For deep burns to the dorsum of the hand and fingers, local flaps are rarely possible, and loco-regional flaps are not feasible in cases of associated upper limb damage. For medium to large surface areas, pedicled inguinal flaps and pocketing are two reliable techniques. Nevertheless, they require relative immobilization of the upper limb, which leads to stiffness. The question of digital pinning in the intrinsic or straight position remains unresolved, and does not appear to prevent secondary deformities. There is also a learning curve for these two flaps, even though they are reputed to be easy to lift. McGregor's flap or pocketing can be weighed against free flaps. However, the operating time is long, the surgical technique is complex, and vascular damage is common in the burn patient population. Although there have been enormous technical advances since their descriptions, the pedicled inguinal flap and pocketing remain alternatives to be considered in the acute management of deep burns to the dorsum of the hand. In this presentation, we propose a surgical management algorithm to situate these two techniques in the plastic surgeon's therapeutic armament.

8.
Neurooncol Adv ; 6(1): vdae056, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38680989

RESUMO

Background: [11C]-Methionine positron emission tomography (PET; [11C]-MET-PET) is principally used for the evaluation of brain tumors in adults. Although amino acid PET tracers are more commonly used in the evaluation of pediatric brain tumors, data on [11C]-MET-PET imaging of pediatric low-grade gliomas (pLGG) is scarce. This study aimed to investigate the roles of [11C]-MET-PET in the evaluation of pLGGs. Methods: Eighteen patients with newly diagnosed pLGG and 26 previously treated pLGG patients underwent [11C]-MET-PET met the inclusion and exclusion criteria. Tumor-to-brain uptake ratio (TBR) and metabolic tumor volumes were assessed for diagnostic performances (newly diagnosed, 15; previously treated 26), change with therapy (newly diagnosed, 9; previously treated 7), and variability among different histology (n = 12) and molecular markers (n = 7) of pLGGs. Results: The sensitivity of [11C]-MET-PET for diagnosing pLGG, newly diagnosed, and previously treated combined was 93% for both TBRmax and TBRpeak, 76% for TBRmean, and 95% for qualitative evaluation. TBRmax showed a statistically significant reduction after treatment, while other PET parameters showed a tendency to decrease. Median TBRmax, TBRpeak, and TBRmean values were slightly higher in the BRAFV600E mutated tumors compared to the BRAF fused tumors. Median TBRmax, and TBRpeak in diffuse astrocytomas were higher compared to pilocytic astrocytomas, but median TBRmean, was slightly higher in pilocytic astrocytomas. However, formal statistical analysis was not done due to the small sample size. Conclusions: Our study shows that [11C]-MET-PET reliably characterizes new and previously treated pLGGs. Our study also shows that quantitative parameters tend to decrease with treatment, and differences may exist between various pLGG types.

9.
Psychotherapy (Chic) ; 61(2): 101-109, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38635213

RESUMO

There have been great strides in psychology regarding diversity, equity, inclusion, and multicultural competence, but a need remains to translate these values into actionable practices in psychotherapy. While the case has been made that measurement-based care is an evidence-based intervention that improves outcomes and reduces dropouts (de Jong et al., 2021) and recently that it provides a transparent collaborative process to engage clients in treatment (Boswell et al., 2023), it has not been widely considered as a methodology for multicultural competence. We trace the evolution of what was once called "patient-focused research" (Lambert, 2001) and identify a significant change in recent writings to include important clinical and collaborative processes, a transition from a strictly normative or nomothetic understanding of the value of feedback to an appreciation of its communicative or idiographic processes. We propose that systematic client feedback promotes a "multicultural orientation" (Owen, 2013) at the individual therapist-client level and that client responses to outcome and process measures can foster cultural humility and create cultural opportunities (Hook et al., 2017) to address marginalization and other sociocultural factors relevant to treatment. Using one system to illustrate what is possible for all feedback approaches, we present client examples that demonstrate an integration of a multicultural orientation. We suggest that systematic client feedback can provide a structure to address diversity, marginalization, and privilege in psychotherapy. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Assuntos
Diversidade Cultural , Relações Profissional-Paciente , Psicoterapia , Humanos , Psicoterapia/métodos , Competência Cultural/psicologia , Retroalimentação
10.
Pediatr Surg Int ; 40(1): 68, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38441654

RESUMO

PURPOSE: To assess the prognostic and therapeutic significance of sentinel lymph node biopsy (SLNB) and completion lymph node dissection (CLND) in pediatric conventional melanoma (CM), while evaluating potential predictive factors for outcomes. METHODS: We conducted a retrospective analysis of medical records spanning 2009-2020, focusing on patients aged 18 or younger with localized cutaneous conventional melanoma. RESULTS: Among the 33 patients, SLNB detected metastasis in 57.6% of cases, with 52.6% undergoing CLND. Positive SLN patients had higher relapse risk (HR 5.92; 95% CI 1.27-27.7; P = 0.024) but similar overall survival (HR 3.19; 95% CI 0.31-33.1, P = 0.33). No significant differences in disease-free survival (DFS) and OS were found between patients who underwent CLND and those who did not (HR 1.91; 95% CI 0.49-7.43, P = 0.35, and HR 0.52; 95% CI 0.03-8.32, P = 0.64, respectively). Univariate analysis showed age at diagnosis (P = 0.02) correlated with higher recurrence risk, with a 21% hazard increase per additional year of age. CONCLUSIONS: Positive SLN status and age at diagnosis were associated with worse DFS in CM patients. Our study did not find any prognostic or therapeutic value in CLND for pediatric melanoma. Further multicenter trials are needed to confirm our single-institution experience. LEVEL OF EVIDENCE: Level IV.


Assuntos
Melanoma , Neoplasias Cutâneas , Humanos , Criança , Melanoma/cirurgia , Estudos Retrospectivos , Linfonodos , Neoplasias Cutâneas/cirurgia , Intervalo Livre de Doença
12.
Global Health ; 20(1): 24, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38528528

RESUMO

The culling of animals that are infected, or suspected to be infected, with COVID-19 has fuelled outcry. What might have contributed to the ongoing debates and discussions about animal rights protection amid global health crises is the lack of a unified understanding and internationally agreed-upon definition of "One Health". The term One Health is often utilised to describe the imperative to protect the health of humans, animals, and plants, along with the overarching ecosystem in an increasingly connected and globalized world. However, to date, there is a dearth of research on how to balance public health decisions that could impact all key stakeholders under the umbrella of One Health, particularly in contexts where human suffering has been immense. To shed light on the issue, this paper discusses whether One Health means "human-centred connected health" in a largely human-dominated planet, particularly amid crises like COVID-19. The insights of this study could help policymakers make more informed decisions that could effectively and efficiently protect human health while balancing the health and well-being of the rest of the inhabitants of our shared planet Earth.


Assuntos
COVID-19 , Saúde Única , Humanos , COVID-19/prevenção & controle , Saúde Global , Saúde Pública
14.
IUCrdata ; 9(Pt 2): x240122, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38455111

RESUMO

The structure of the title complex, [Zn2(C2H3O2)4(C11H9N3O)2], is triclinic containing half of the mol-ecule in the asymmetric unit. Each zinc atom is coordinated to a pyridyl and oxime nitro-gen from one di-2-pyridyl ketone oxime (dpko) ligand and a third nitro-gen from the other dpko pyridyl ring. Additionally, each zinc is coordinated to two acetato anions, one of which is bidentate and the other monodentate. The uncoordinated oxygen of the monodentate acetato group is involved in a hydrogen bond with the oxime hydrogen. The packing in the crystal is assisted by weak C-H⋯O inter-actions between acetato groups and neighboring pyridyl rings.

15.
Nat Commun ; 15(1): 1918, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429271

RESUMO

The combination of a geometrically frustrated lattice, and similar energy scales between degrees of freedom endows two-dimensional Kagome metals with a rich array of quantum phases and renders them ideal for studying strong electron correlations and band topology. The Kagome metal, FeGe is a noted example of this, exhibiting A-type collinear antiferromagnetic (AFM) order at TN ≈ 400 K, then establishes a charge density wave (CDW) phase coupled with AFM ordered moment below TCDW ≈ 110 K, and finally forms a c-axis double cone AFM structure around TCanting ≈ 60 K. Here we use neutron scattering to demonstrate the presence of gapless incommensurate spin excitations associated with the double cone AFM structure of FeGe at temperatures well above TCanting and TCDW that merge into gapped commensurate spin waves from the A-type AFM order. Commensurate spin waves follow the Bose factor and fit the Heisenberg Hamiltonian, while the incommensurate spin excitations, emerging below TN where AFM order is commensurate, start to deviate from the Bose factor around TCDW, and peaks at TCanting. This is consistent with a critical scattering of a second order magnetic phase transition with decreasing temperature. By comparing these results with density functional theory calculations, we conclude that the incommensurate magnetic structure arises from the nested Fermi surfaces of itinerant electrons and the formation of a spin density wave order.

16.
Clin Infect Dis ; 78(5): 1148-1153, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38441140

RESUMO

Fever of unknown origin (FUO) is a clinical conundrum for patients and clinicians alike, and imaging studies are often performed as part of the diagnostic workup of these patients. Recently, the Society of Nuclear Medicine and Molecular Imaging convened and approved a guideline on the use of nuclear medicine tools for FUO. The guidelines support the use of 2-18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) in adults and children with FUO. 18F-FDG PET/CT allows detection and localization of foci of hypermetabolic lesions with high sensitivity because of the 18F-FDG uptake in glycolytically active cells that may represent inflammation, infection, or neoplasia. Clinicians should consider and insurers should cover 18F-FDG PET/CT when evaluating patients with FUO, particularly when other clinical clues and preliminary studies are unrevealing.


Assuntos
Febre de Causa Desconhecida , Fluordesoxiglucose F18 , Medicina Nuclear , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Humanos , Febre de Causa Desconhecida/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Medicina Nuclear/métodos , Adulto , Compostos Radiofarmacêuticos , Criança , Guias de Prática Clínica como Assunto
18.
Semin Nucl Med ; 54(3): 313-331, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38423851

RESUMO

Soft tissue sarcomas account for 6%-8% of pediatric cancers. The rhabdomyosarcoma family is the most frequent soft tissue sarcoma in this age group accounting for 3% of pediatric cancers. Rhabdomyosarcomas are high-grade tumors with a high propensity to metastasize. The risk-adapted, multimodal therapeutic approach for rhabdomyosarcomas incorporates a combination of surgery, radiotherapy, and multi-agent cytotoxic chemotherapy. Soft tissue sarcomas other than rhabdomyosarcoma account for 3%-4% of pediatric cancers. The nonrhabdomyosarcoma soft tissue sarcomas include both low-grade and high-grade tumors. While surgery is the mainstay of therapy in most non-rhabdomyosarcoma soft tissue sarcomas, many cases require a multimodal therapeutic approach including radiotherapy and chemotherapy. In North America, most pediatric patients with soft tissue sarcomas are treated in Children's Oncology Group clinical trials. In this article, we will primarily focus on the staging, risk stratification, imaging recommendations, and interpretations in accordance with the Children's Oncology Group trials. We will review the results and recommendations of International Soft Tissue Sarcoma Database Consortium and European trials in relevant sections where they provide complementary guidelines.


Assuntos
Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Sarcoma , Humanos , Sarcoma/diagnóstico por imagem , Sarcoma/terapia
20.
Psychother Res ; 34(3): 311-322, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37523612

RESUMO

OBJECTIVE: The culturally salient fear of losing face might influence Chinese therapists' attitudes toward and use of routine outcome monitoring (ROM). We tested a model wherein self-face concern is associated with ROM use by way of attitudes toward ROM, and whether this process is weakened when therapists report high counseling self-efficacy and perspective-taking. METHOD: A national sample of Chinese mental health professionals (N = 371) completed questionnaires on their fear of losing face, attitudes toward ROM, ROM use, counseling self-efficacy, and perspective-taking. RESULTS: Regression-based analyses showed that fear of losing face was linked to greater negative attitudes toward ROM and lower ROM use. Greater negative attitudes mediated the relationship between fear of losing face and ROM use. However, neither counseling self-efficacy nor perspective-taking mitigated the relationship between self-face concern and ROM use; instead, they exacerbated this relationship through different paths. In the mediated pathway, counseling self-efficacy in coping with clients with difficult problems interacted with self-face concern to predict negative attitudes toward ROM. Perspective-taking served as a moderator that exacerbated the direct relationship between self-face concern and ROM use. CONCLUSIONS: Findings suggest the importance of considering culturally salient factors in implementing ROM in China and other non-Western contexts.


Assuntos
Pessoal de Saúde , Saúde Mental , Humanos , Atitude do Pessoal de Saúde , China , Medo
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