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1.
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
3.
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
4.
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
5.
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
6.
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
7.
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.

9.
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.

10.
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
11.
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
12.
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
13.
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
14.
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.

15.
Sci Adv ; 8(50): eade2067, 2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36525483

RESUMO

The extraterrestrial materials returned from asteroid (162173) Ryugu consist predominantly of low-temperature aqueously formed secondary minerals and are chemically and mineralogically similar to CI (Ivuna-type) carbonaceous chondrites. Here, we show that high-temperature anhydrous primary minerals in Ryugu and CI chondrites exhibit a bimodal distribution of oxygen isotopic compositions: 16O-rich (associated with refractory inclusions) and 16O-poor (associated with chondrules). Both the 16O-rich and 16O-poor minerals probably formed in the inner solar protoplanetary disk and were subsequently transported outward. The abundance ratios of the 16O-rich to 16O-poor minerals in Ryugu and CI chondrites are higher than in other carbonaceous chondrite groups but are similar to that of comet 81P/Wild2, suggesting that Ryugu and CI chondrites accreted in the outer Solar System closer to the accretion region of comets.

16.
JAMA ; 328(20): 2056-2057, 2022 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-36413249

RESUMO

This article summarizes guidelines on identifying and addressing infertility in men from the American Urological Association and American Society for Reproductive Medicine.


Assuntos
Infertilidade Masculina , Humanos , Masculino , Infertilidade Masculina/diagnóstico , Infertilidade Masculina/etiologia , Infertilidade Masculina/terapia
17.
Sci Adv ; 8(46): eadd8141, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36264823

RESUMO

Little is known about the origin of the spectral diversity of asteroids and what it says about conditions in the protoplanetary disk. Here, we show that samples returned from Cb-type asteroid Ryugu have Fe isotopic anomalies indistinguishable from Ivuna-type (CI) chondrites, which are distinct from all other carbonaceous chondrites. Iron isotopes, therefore, demonstrate that Ryugu and CI chondrites formed in a reservoir that was different from the source regions of other carbonaceous asteroids. Growth and migration of the giant planets destabilized nearby planetesimals and ejected some inward to be implanted into the Main Belt. In this framework, most carbonaceous chondrites may have originated from regions around the birthplaces of Jupiter and Saturn, while the distinct isotopic composition of CI chondrites and Ryugu may reflect their formation further away in the disk, owing their presence in the inner Solar System to excitation by Uranus and Neptune.

18.
ACS Synth Biol ; 11(10): 3182-3189, 2022 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-36223492

RESUMO

The heterodimeric transcription factor, hypoxia inducible factor-1 (HIF-1), is an important anticancer target as it supports the adaptation and response of tumors to hypoxia. Here, we optimized the repressed transactivator yeast two-hybrid system to further develop it as part of a versatile yeast-based drug discovery platform and validated it using HIF-1. We demonstrate both fluorescence-based and auxotrophy-based selections that could detect HIF-1α/HIF-1ß dimerization inhibition. The engineered genetic selection is tunable and able to differentiate between strong and weak interactions, shows a large dynamic range, and is stable over different growth phases. Furthermore, we engineered mechanisms to control for cellular activity and off-target drug effects. We thoroughly characterized all parts of the biosensor system and argue this tool will be generally applicable to a wide array of protein-protein interaction targets. We anticipate this biosensor will be useful as part of a drug discovery platform, particularly when screening DNA-encoded new modality drugs.


Assuntos
Técnicas Biossensoriais , Fator 1 Induzível por Hipóxia , Humanos , Hipóxia , Descoberta de Drogas , Transativadores
19.
Biochem Pharmacol ; 204: 115226, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36027928

RESUMO

LAS200813 is a novel bicyclic lipopeptide that activates Nrf2 by binding to Keap1, thereby antagonising the Keap1-Nrf2 protein-protein interaction. In this work we report the pharmacological characterization of LAS200813 in Nrf2-dependent translational preclinical models. LAS200813 binds to Keap1 with high affinity (IC50: 0.73 nM) and is able to induce the translocation of Nrf2 to the nucleus. Furthermore, LAS200813 increases the expression of Nrf2 target genes in human bronchial epithelial cells (EC50 of 96 and 70 nM for srxn1 and nqo1, respectively). Similarly, the intratracheal administration of LAS200813 to rats increases the expression of Nrf2-dependent genes in lung tissue, an effect that lasts for a few hours. Moreover, in cells exposed to cigarette smoke, LAS200813 shows an antioxidant effect by increasing the production of glutathione and prevents cellular apoptosis. In conclusion, the results described herein demonstrate that LAS200813 is a potent non-electrophilic Nrf2-activating peptide designed to be administered by inhaled route which may be a potential therapeutic strategy for respiratory diseases driven by oxidative stress.


Assuntos
Antioxidantes , Proteína 1 Associada a ECH Semelhante a Kelch , Lipopeptídeos , Fator 2 Relacionado a NF-E2 , Animais , Antioxidantes/farmacologia , Glutationa/metabolismo , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Lipopeptídeos/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Ratos
20.
Clin Diabetes ; 40(3): 366-369, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35983427

RESUMO

Quality Improvement Success Stories are published by the American Diabetes Association in collaboration with the American College of Physicians and the National Diabetes Education Program. This series is intended to highlight best practices and strategies from programs and clinics that have successfully improved the quality of care for people with diabetes or related conditions. Each article in the series is reviewed and follows a standard format developed by the editors of Clinical Diabetes. The following article describes an effort to reduce iatrogenic insulin-associated hypoglycemia at the University of Chicago Medical Center in Chicago, IL.

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