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1.
JAMA ; 2024 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-39446318

RESUMO

This JAMA Clinical Guidelines Synopsis summarizes the Wilderness Medical Society's 2024 recommendations on prevention, diagnosis, and treatment of acute altitude illness.

2.
JAMA ; 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39259567

RESUMO

This JAMA Clinical Guidelines Synopsis summarizes the 2022 recommendations on evaluation of suspected antibiotic allergies from the American Academy of Allergy, Asthma & Immunology and American College of Allergy, Asthma & Immunology.

3.
Sci Adv ; 10(39): eadp2426, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39331721

RESUMO

The isotopic compositions of samples returned from Cb-type asteroid Ryugu and Ivuna-type (CI) chondrites are distinct from other carbonaceous chondrites, which has led to the suggestion that Ryugu/CI chondrites formed in a different region of the accretion disk, possibly around the orbits of Uranus and Neptune. We show that, like for Fe, Ryugu and CI chondrites also have indistinguishable Ni isotope anomalies, which differ from those of other carbonaceous chondrites. We propose that this unique Fe and Ni isotopic composition reflects different accretion efficiencies of small FeNi metal grains among the carbonaceous chondrite parent bodies. The CI chondrites incorporated these grains more efficiently, possibly because they formed at the end of the disk's lifetime, when planetesimal formation was also triggered by photoevaporation of the disk. Isotopic variations among carbonaceous chondrites may thus reflect fractionation of distinct dust components from a common reservoir, implying CI chondrites/Ryugu may have formed in the same region of the accretion disk as other carbonaceous chondrites.

4.
JAMA ; 332(12): 1013-1014, 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39207780
6.
J Am Coll Radiol ; 21(6S): S292-S309, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38823951

RESUMO

Sepsis is defined as a life-threatening organ dysfunction caused by a dysregulated host response to infection. A search for the underlying cause of infection typically includes radiological imaging as part of this investigation. This document focuses on thoracic and abdominopelvic causes of sepsis. In 2017, the global incidence of sepsis was estimated to be 48.9 million cases, with 11 million sepsis-related deaths (accounting for nearly 20% of all global deaths); therefore, understanding which imaging modalities and types of studies are acceptable or not acceptable is imperative. The 5 variants provided include the most commonly encountered scenarios in the setting of sepsis along with recommendations and data for each imaging study. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.


Assuntos
Medicina Baseada em Evidências , Sepse , Sociedades Médicas , Humanos , Sepse/diagnóstico por imagem , Estados Unidos , Diagnóstico por Imagem/normas
7.
Sci Adv ; 10(11): eadj6406, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38489355

RESUMO

There is a compelling need to find drugs active against Mycobacterium tuberculosis (Mtb). 4'-Phosphopantetheinyl transferase (PptT) is an essential enzyme in Mtb that has attracted interest as a potential drug target. We optimized a PptT assay, used it to screen 422,740 compounds, and identified raltitrexed, an antineoplastic antimetabolite, as the most potent PptT inhibitor yet reported. While trying unsuccessfully to improve raltitrexed's ability to kill Mtb and remove its ability to kill human cells, we learned three lessons that may help others developing antibiotics. First, binding of raltitrexed substantially changed the configuration of the PptT active site, complicating molecular modeling of analogs based on the unliganded crystal structure or the structure of cocrystals with inhibitors of another class. Second, minor changes in the raltitrexed molecule changed its target in Mtb from PptT to dihydrofolate reductase (DHFR). Third, the structure-activity relationship for over 800 raltitrexed analogs only became interpretable when we quantified and characterized the compounds' intrabacterial accumulation and transformation.


Assuntos
Mycobacterium tuberculosis , Neoplasias , Quinazolinas , Tiofenos , Transferases (Outros Grupos de Fosfato Substituídos) , Humanos , Mycobacterium tuberculosis/metabolismo , Timidilato Sintase/metabolismo , Proteínas de Bactérias/metabolismo
8.
JAMA ; 331(13): 1145-1146, 2024 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-38483370

RESUMO

This JAMA Clinical Guidelines Synopsis summarizes the Endocrine Society's 2023 recommendations on management of outpatients with diabetes and high risk of hypoglycemia.


Assuntos
Assistência Ambulatorial , Diabetes Mellitus , Hipoglicemia , Humanos , Diabetes Mellitus/terapia , Hipoglicemia/induzido quimicamente , Hipoglicemia/etiologia , Risco
9.
JAMA ; 331(12): 1055-1056, 2024 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-38451547

RESUMO

This article summarizes a 2022 clinical practice guideline on the use of disease-modifying antirheumatic drugs (DMARDs) for adults with rheumatoid arthritis from the European League Against Rheumatism (EULAR).


Assuntos
Antirreumáticos , Artrite Reumatoide , Adulto , Humanos , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Resultado do Tratamento , Idade de Início
11.
Antimicrob Agents Chemother ; 68(3): e0106423, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38349161

RESUMO

Screening a library of 1,200 preselected kinase inhibitors for anti-human rhinovirus 2 (HRV-2) activity in HeLa cells identified a class of epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKI) as effective virus blockers. These were based on the 4-anilinoquinazoline-7-oxypiperidine scaffold, with the most potent representative AZ5385 inhibiting the virus with EC50 of 0.35 µM. Several structurally related analogs confirmed activity in the low µM range, while interestingly, other TKIs targeting EGFR lacked anti-HRV-2 activity. To further probe this lack of association between antiviral activity and EGFR inhibition, we stained infected cells with antibodies specific for activated EGFR (Y1068) and did not observe a dependency on EGFR-TK activity. Instead, consecutive passages of HRV-2 in HeLa cells in the presence of a compound and subsequent nucleotide sequence analysis of resistant viral variants identified the S181T and T210A alterations in the major capsid VP1 protein, with both residues located in the vicinity of a known hydrophobic pocket on the viral capsid. Further characterization of the antiviral effects of AZ5385 showed a modest virus-inactivating (virucidal) activity, while anti-HRV-2 activity was still evident when the inhibitor was added as late as 10 h post infection. The RNA copy/infectivity ratio of HRV-2 propagated in AZ5385 presence was substantially higher than that of control HRV indicating that the compound preferentially targeted HRV progeny virions during their maturation in infected cells. Besides HRV, the compound showed anti-respiratory syncytial virus activity, which warrants its further studies as a candidate compound against viral respiratory infections.


Assuntos
Rhinovirus , Humanos , Rhinovirus/química , Rhinovirus/genética , Células HeLa , Proteínas do Capsídeo , Antivirais/química , Receptores ErbB
12.
Anal Chem ; 96(1): 170-178, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38155534

RESUMO

Characterization of the elemental distribution of samples with rough surfaces has been strongly desired for the analysis of various natural and artificial materials. Particularly for pristine and rare analytes with micrometer sizes embedded on specimen surfaces, non-invasive and matrix effect-free analysis is required without surface polishing treatment. To satisfy these requirements, we proposed a new method employing the sequential combination of two imaging modalities, i.e., microenergy-dispersive X-ray fluorescence (micro-XRF) and Raman micro-spectroscopy. The applicability of the developed method is tested by the quantitative analysis of cation composition in micrometer-sized carbonate grains on the surfaces of intact particles sampled directly from the asteroid Ryugu. The first step of micro-XRF imaging enabled a quick search for the sparsely scattered and micrometer-sized carbonates by the codistributions of Ca2+ and Mn2+ on the Mg2+- and Fe2+-rich phyllosilicate matrix. The following step of Raman micro-spectroscopy probed the carbonate grains and analyzed their cation composition (Ca2+, Mg2+, and Fe2+ + Mn2+) in a matrix effect-free manner via the systematic Raman shifts of the lattice modes. The carbonates were basically assigned to ferroan dolomite bearing a considerable amount of Fe2+ + Mn2+ at around 10 atom %. These results are in good accordance with the assignments reported by scanning electron microscopy-energy-dispersive X-ray spectroscopy, where the thin-sectioned and surface-polished Ryugu particles were applicable. The proposed method requires neither sectioning nor surface polishing; hence, it can be applied to the remote sensing apparatus on spacecrafts and planetary rovers. Furthermore, the non-invasive and matrix effect-free characterization will provide a reliable analytical tool for quantitative analysis of the elemental distribution on the samples with surface roughness and chemical heterogeneity at a micrometer scale, such as art paintings, traditional crafts with decorated shapes, as well as sands and rocks with complex morphologies in nature.

13.
JAMA ; 331(4): 352-353, 2024 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-38127327

RESUMO

This JAMA Clinical Guidelines Synopsis summarizes the 2022 American College of Cardiology/American Heart Association guidelines for diagnosis and management of aortic disease.


Assuntos
Doenças da Aorta , Doenças das Valvas Cardíacas , Humanos , Estados Unidos , Doenças da Aorta/diagnóstico , Doenças da Aorta/terapia , Doenças das Valvas Cardíacas/diagnóstico , American Heart Association
15.
Sci Adv ; 9(45): eadi7048, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37939187

RESUMO

Studies of material returned from Cb asteroid Ryugu have revealed considerable mineralogical and chemical heterogeneity, stemming primarily from brecciation and aqueous alteration. Isotopic anomalies could have also been affected by delivery of exogenous clasts and aqueous mobilization of soluble elements. Here, we show that isotopic anomalies for mildly soluble Cr are highly variable in Ryugu and CI chondrites, whereas those of Ti are relatively uniform. This variation in Cr isotope ratios is most likely due to physicochemical fractionation between 54Cr-rich presolar nanoparticles and Cr-bearing secondary minerals at the millimeter-scale in the bulk samples, likely due to extensive aqueous alteration in their parent bodies that occurred [Formula: see text] after Solar System birth. In contrast, Ti isotopes were marginally affected by this process. Our results show that isotopic heterogeneities in asteroids are not all nebular or accretionary in nature but can also reflect element redistribution by water.

16.
JAMA ; 330(17): 1687-1688, 2023 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-37843854

RESUMO

This JAMA Clinical Guidelines Synopsis summarizes the American Association of Clinical Endocrinology's 2022 clinical practice guideline for diagnosis and management of nonalcoholic fatty liver disease.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Fígado , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/terapia
17.
JAMA ; 330(6): 559-560, 2023 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-37471069

RESUMO

This JAMA Clinical Guidelines Synopsis summarizes the 2022 American Urological Association/Sexual Medicine Society of North America guidelines on diagnosis and management of priapism.


Assuntos
Disfunção Erétil , Priapismo , Masculino , Humanos , Priapismo/diagnóstico , Priapismo/etiologia , Priapismo/terapia , Pênis
18.
Sci Adv ; 9(28): eadh1003, 2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37450600

RESUMO

Preliminary analyses of asteroid Ryugu samples show kinship to aqueously altered CI (Ivuna-type) chondrites, suggesting similar origins. We report identification of C-rich, particularly primitive clasts in Ryugu samples that contain preserved presolar silicate grains and exceptional abundances of presolar SiC and isotopically anomalous organic matter. The high presolar silicate abundance (104 ppm) indicates that the clast escaped extensive alteration. The 5 to 10 times higher abundances of presolar SiC (~235 ppm), N-rich organic matter, organics with N isotopic anomalies (1.2%), and organics with C isotopic anomalies (0.2%) in the primitive clasts compared to bulk Ryugu suggest that the clasts formed in a unique part of the protoplanetary disk enriched in presolar materials. These clasts likely represent previously unsampled outer solar system material that accreted onto Ryugu after aqueous alteration ceased, consistent with Ryugu's rubble pile origin.


Assuntos
Carbono , Meteoroides , Carbono/análise , Sistema Solar , Silicatos
19.
JAMA ; 329(21): 1872-1874, 2023 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-37200007

RESUMO

This article summarizes the recent update of guidelines on health care for transgender and gender diverse people, including primary care, gender-affirming care, mental health care, and education of the clinical workforce.


Assuntos
Atenção à Saúde , Assistência ao Paciente , Minorias Sexuais e de Gênero , Padrão de Cuidado , Humanos , Atenção à Saúde/normas , Identidade de Gênero , Pessoas Transgênero , Assistência ao Paciente/normas
20.
Science ; 379(6634): eabn7850, 2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35679354

RESUMO

Carbonaceous meteorites are thought to be fragments of C-type (carbonaceous) asteroids. Samples of the C-type asteroid (162173) Ryugu were retrieved by the Hayabusa2 spacecraft. We measured the mineralogy and bulk chemical and isotopic compositions of Ryugu samples. The samples are mainly composed of materials similar to those of carbonaceous chondrite meteorites, particularly the CI (Ivuna-type) group. The samples consist predominantly of minerals formed in aqueous fluid on a parent planetesimal. The primary minerals were altered by fluids at a temperature of 37° ± 10°C, about [Formula: see text] million (statistical) or [Formula: see text] million (systematic) years after the formation of the first solids in the Solar System. After aqueous alteration, the Ryugu samples were likely never heated above ~100°C. The samples have a chemical composition that more closely resembles that of the Sun's photosphere than other natural samples do.

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