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1.
Z Orthop Unfall ; 162(4): 429-443, 2024 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-39116860

RESUMO

Around a third of all cervical spine injuries occur in the upper cervical spine in the area between the occiput and the second cervical vertebra. The latter being the most common location of the injury with around 70%. But also atlas fractures, occipital condyle fractures, traumatic spondylolisthesis of C2, atypical fractures in the corpus area as well as atlantooccipital and atlantoaxial ligamentous lesions should be mentioned in connection with injuries in this area. In many cases, conservative therapy regimen is possible. In unstable or displaced injuries, however, surgical intervention is required, with various surgical procedures being used. The frequency, diagnostics, classification, and standard therapy of the individual entities are presented in detail in this continuing medical education article.


Assuntos
Vértebras Cervicais , Fraturas da Coluna Vertebral , Humanos , Vértebras Cervicais/lesões , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/cirurgia , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/classificação , Fraturas da Coluna Vertebral/cirurgia , Fraturas da Coluna Vertebral/terapia , Fraturas da Coluna Vertebral/diagnóstico , Fusão Vertebral/métodos , Traumatismos da Coluna Vertebral/classificação , Traumatismos da Coluna Vertebral/diagnóstico por imagem , Traumatismos da Coluna Vertebral/diagnóstico , Traumatismos da Coluna Vertebral/cirurgia , Traumatismos da Coluna Vertebral/terapia , Espondilolistese/cirurgia , Espondilolistese/diagnóstico por imagem , Espondilolistese/classificação
2.
ACS Nano ; 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39133043

RESUMO

Cylindrical vector (CV) beams exhibit spatially varying polarization important in optical communication, super-resolution microscopy, and high-throughput information processing. Compared to radially or azimuthally polarized CV beams that are cylindrically symmetric, hybrid-electric (HE) beams offer increased optical tunability because of their polygonally symmetric polarizations. However, efforts to generate and isolate HE beams have relied on bulky optical assemblies or devices with complex and stringent fabrication requirements. Here, we report a moiré-based metasurface approach to engineer HE polarization states with high degrees of rotational symmetry. Importantly, polarization symmetries can be tailored based only on the reciprocal lattice of the metasurface and not the real-space patterns. Our modular method outlines important design principles for shaping light at the nanoscale.

3.
Front Physiol ; 15: 1379739, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39129753

RESUMO

Physical inactivity and sedentary behaviour are important risk factors for cardiovascular disease. Knowledge about the impact of everyday movements on cardiac autonomic regulation is sparse. This study aims to provide evidence that typical everyday movements show a clear impact on heart rate regulation. 40 healthy participants performed two everyday movements: (1) calmly kneeling down ("tie one's shoes") and standing up again and (2) raising the arms to the horizontal ("expressive yawning"). Both movements elicited reproducible pattern in the sequence of heart periods. Local minima and local maxima appeared in the transient period of approx. 30 s. The regulatory response for ergometer cycling, which was used as control, did not show a pattern formation. Calmly performed everyday movements are able to elicit rich cardiac regulatory responses including specific patterns in heart rate. These newly described patterns have multiple implications for clinical and rehabilitative medicine, basic research, digital health data processing, and public health. If carried out regularly these regulatory responses may help to mitigate the burden of physical inactivity and enrich cardiovascular regulation.

4.
Br J Haematol ; 2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38973132

RESUMO

Management of immune thrombocytopenia (ITP) beyond initial glucocorticoid therapy is challenging. In this retrospective single-centre cohort study, we compared all ITP patients relapsed or non-responsive to glucocorticoid therapy treated with either continuous TPO-RAs (n = 35) or rituximab induction (n = 20) between 2015 and 2022. While both groups showed high initial complete response rates (CR, 68.6 vs. 80.0%, ns), the overall rate of progression to the next therapy was higher after time-limited rituximab (75.0 vs. 42.9%), resulting in a lower relapse-free survival (median 16.6 vs. 25.8 months, log-rank; p < 0.05). We conclude that both treatments show similar initial efficacy and their ideal duration of therapy warrants further investigation.

6.
Orphanet J Rare Dis ; 19(1): 259, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982319

RESUMO

BACKGROUND: Fabry disease (FD), an X-linked lysosomal storage disorder, is caused by mutations in the gene encoding α-galactosidase A, resulting in lysosomal accumulation of globotriaosylceramide and other glycosphingolipids. Early detection of FD is challenging, accounting for delayed diagnosis and treatment initiation. This study aimed to develop an algorithm using a logistic regression model to facilitate early identification of patients based on ICD-10-GM coding using a German Sickness Fund Database. METHODS: The logistic regression model was fitted on a binary outcome variable based on either a treated FD cohort or a control cohort (without FD). Comorbidities specific to the involved organs were used as covariates to identify potential FD patients with ICD-10-GM E75.2 diagnosis but without any FD-specific medication. Specificity and sensitivity of the model were optimized to determine a likely threshold. The cut-point with the largest values for the Youden index and concordance probability method and the lowest value for closest to (0,1) was identified as 0.08 for each respective value. The sensitivity and specificity for this cut-point were 80.4% and 79.8%, respectively. Additionally, a sensitivity analysis of the potential FD patients with at least two codes of E75.2 diagnoses was performed. RESULTS: A total of 284 patients were identified in the potential FD cohort using the logistic regression model. Most potential FD patients were < 30 years old and female. The identification and incidence rates of FD in the potential FD cohort were markedly higher than those of the treated FD cohort. CONCLUSIONS: This model serves as a tool to identify potential FD patients using German insurance claims data.


Assuntos
Algoritmos , Doença de Fabry , Doença de Fabry/diagnóstico , Doença de Fabry/genética , Doença de Fabry/epidemiologia , Humanos , Alemanha , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Modelos Logísticos , Bases de Dados Factuais , Adolescente , Idoso
7.
Chem Res Toxicol ; 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39053905

RESUMO

Over several years, e-liquids with "nicotine salts" have gained considerable popularity. These e-liquids have a low pH, at which nicotine occurs mostly in its monoprotonated form. Manufacturers usually accomplish this by the addition of an organic acid, such as levulinic acid, benzoic acid, or lactic acid. Nicotine in its protonated form can be more easily inhaled, enhancing the addictiveness and attractiveness of products. Several techniques have been described for measuring the protonation state of nicotine in e-liquids. However, nuclear magnetic resonance (NMR) spectroscopy is particularly suited for this purpose because it can be performed on unaltered e-liquids. In this article, we demonstrate the suitability of a benchtop NMR (60 MHz) instrument for determining the protonation state of nicotine in e-liquids. The method is subsequently applied to measure the protonation state of 33 commercially available e-liquids and to investigate whether the vaping process alters the protonation state of nicotine. For this purpose, the protonation state in the condensed aerosol obtained by automated vaping of different e-liquids was compared with that of the original e-liquids. Two distinct populations were observed in the protonation state of nicotine in commercial e-liquids: free-base (fraction of free-base nicotine αfb > 0.80) and protonated (αfb < 0.40). For 30 e-liquids out of 33, the information on the packaging regarding the presence of nicotine salt was in agreement with the observed protonation state. Three e-liquids contained nicotine salt, even though this was not stated on the packaging. Measuring the protonation state of nicotine before and after (machine) vaping revealed that the protonation state of e-liquids is not affected by vaping. In conclusion, it is possible to determine the nicotine protonation state with the described method. Two clusters can be distinguished in the protonation state of commercial e-liquids, and the protonation state of nicotine remains unchanged after vaping.

8.
Ann Hematol ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39020041

RESUMO

Further line treatment of patients with advanced stage AL amyloidosis with cardiac involvement is challenging. Venetoclax is a promising option, especially in t(11;14) and BCL2 expression.In our multicentre observational study, we report the 3-year follow-up of Venetoclax treatment in 9 patients with advanced, relapsed or refractory AL amyloidosis with t(11;14) and BCL-2 expression in > 50% of plasma cells. At baseline, all patients had been previously treated with daratumumab, all had cardiac involvement with revised Mayo stage III or IV/ European modification of Mayo 2004 IIIA or IIIB (1/9 unclassified due to missing troponin T), 5/9 patients had renal involvement.After a median of 35 months (range 25-49) since the start of Venetoclax, 8/9 patients were still alive (OS 89%). First and best hematological responses were observed after a median of 26 days (11-125) and 106 days (35-659), overall response rate was 100% (7/9 CR, 2/9 VGPR). Where observed, organ response was documented within the first 6 months of therapy, including cardiac (6/9) and renal (3/5) improvements. Venetoclax was discontinued in 6/9 patients after a median of 15 months (11-48) due to toxicity (2/9), disease progression (2/9), fixed treatment duration (1/9), or safety concerns (1/9).In conclusion, Venetoclax induces a rapid and deep hematologic response with consistent improvement in organ function with an acceptable safety profile in patients with pretreated, advanced stage AL amyloidosis with cardiac involvement and BCL2 expression with and potentially without detected t(11:14), which warrants further investigation.

9.
J Am Chem Soc ; 146(31): 22027-22035, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39052634

RESUMO

The development of a flow chemistry platform for the generation of modified protein targets via expressed protein ligation (EPL) is described. The flow EPL platform enables efficient ligation reactions with high recoveries of target protein products and superior reaction rates compared to corresponding batch processes. The utility of the flow EPL technology was first demonstrated through the semisynthesis of the tick-derived chemokine-binding protein ACA-01 containing two tyrosine sulfate modifications. Full-length, sulfated ACA-01 could be efficiently assembled by ligating a recombinantly expressed C-terminal protein fragment and a synthetic sulfopeptide thioester in flow. Following folding, the semisynthetic sulfoprotein was shown to exhibit potent binding to a variety of pro-inflammatory chemokines. In a second modified protein target, we employed an in-line flow EPL-photodesulfurization strategy to generate both unmodified and phosphorylated forms of human ß-synuclein by fusing a recombinant protein thioester, generated through cleavage of an intein fusion protein, and a synthetic (phospho)peptide. The semisynthetic proteins were assembled in 90 min in flow, a significant improvement over corresponding batch protein assembly, and enabled access to tens of milligrams of high purity material. Flow EPL has the potential to serve as a robust technology to streamline access to homogeneously modified proteins for a variety of applications in both academia, as well as in the pharmaceutical and biotechnology sector.


Assuntos
Humanos
10.
bioRxiv ; 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38826346

RESUMO

The paenilamicins are a group of hybrid non-ribosomal peptide-polyketide compounds produced by the honey bee pathogen Paenibacillus larvae that display activity against Gram-positive pathogens, such as Staphylococcus aureus. While paenilamicins have been shown to inhibit protein synthesis, their mechanism of action has remained unclear. Here, we have determined structures of the paenilamicin PamB2 stalled ribosomes, revealing a unique binding site on the small 30S subunit located between the A- and P-site tRNAs. In addition to providing a precise description of interactions of PamB2 with the ribosome, the structures also rationalize the resistance mechanisms utilized by P. larvae. We could further demonstrate that PamB2 interferes with the translocation of mRNA and tRNAs through the ribosome during translation elongation, and that this inhibitory activity is influenced by the presence of modifications at position 37 of the A-site tRNA. Collectively, our study defines the paenilamicins as a new class of context-specific translocation inhibitors.

11.
Chemistry ; : e202401674, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38839567

RESUMO

Nitrile-aminothiol conjugation (NATC) stands out as a promising biocompatible ligation technique due to its high chemo-selectivity. Herein we investigated the reactivity and substrate scope of NAT conjugation chemistry, thus developing a novel pH dependent orthogonal NATC as a valuable tool for chemical biology. The study of reaction kinetics elucidated that the combination of heteroaromatic nitrile and aminothiol groups led to the formation of an optimal bioorthogonal pairing, which is pH dependent. This pairing system was effectively utilized for sequential and dual conjugation. Subsequently, these rapid (≈1 h) and high yield (>90 %) conjugation strategies were successfully applied to a broad range of complex biomolecules, including oligonucleotides, chelates, small molecules and peptides. The effectiveness of this conjugation chemistry was demonstrated by synthesizing a fluorescently labelled antimicrobial peptide-oligonucleotide complex as a dual conjugate to imaging in live cells. This first-of-its-kind sequential NATC approach unveils unprecedented opportunities in modern chemical biology, showcasing exceptional adaptability in rapidly creating structurally complex bioconjugates. Furthermore, the results highlight its potential for versatile applications across fundamental and translational biomedical research.

12.
Waste Manag ; 186: 86-93, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38865908

RESUMO

As part of its commitment to the United Nations Framework Convention on Climate Change, the U.S. annually develops a national estimate of methane emissions from municipal solid waste (MSW) landfills by aggregating activity data from each facility. Since 2010, the U.S. has reported a 20 % decrease in MSW landfill emissions despite a 21 % increase in tons disposed. Operator-submitted data were investigated to understand the causes of this decline. In the U.S., operators of landfills with a gas collection and control system (GCCS) calculate their facility's emissions via two separate approaches - (1) first-order decay (FOD) and (2) collection efficiency assumption (CEA) - and select either result to feed into the annual inventory. The FOD model predicts methane generation proportional to waste disposal and that approach calculated a 19 % increase in total methane generated from 2010 to 2022, whereas generation via the CEA approach decreased by 8.9 %. The amount of measured methane collected has increased 7.5 % for the same years. Discrepancies between the two models' generated methane, assumed gas collection efficiencies, and oxidized methane compound into substantive differences in national estimates. Operators more frequently select the CEA method, which results in decreased national estimates. If only the FOD method was used, U.S. MSW landfill emissions would be 1.3-1.7 times greater than current estimates which is similar to recent extrapolations from remote sensing campaigns in the U.S. Both models contain parameters with large inherent uncertainty. Without measurement methods that continuously quantify both point-source and diffuse emissions, an assessment of either equation's accuracy cannot be made.


Assuntos
Poluentes Atmosféricos , Metano , Modelos Teóricos , Eliminação de Resíduos , Instalações de Eliminação de Resíduos , Metano/análise , Estados Unidos , Poluentes Atmosféricos/análise , Eliminação de Resíduos/métodos , Gases de Efeito Estufa/análise , Monitoramento Ambiental/métodos , Resíduos Sólidos/análise
13.
ACS Chem Biol ; 19(7): 1426-1432, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-38941516

RESUMO

Chemokines are an important family of small proteins integral to leukocyte recruitment during inflammation. Dysregulation of the chemokine-chemokine receptor axis is implicated in many diseases, and both chemokines and their cognate receptors have been the targets of therapeutic development. Analysis of the antigen-binding regions of chemokine-binding nanobodies revealed a sequence motif suggestive of tyrosine sulfation. Given the well-established importance of post-translational tyrosine sulfation of receptors for chemokine affinity, it was hypothesized that the sulfation of these nanobodies may contribute to chemokine binding and selectivity. Four nanobodies (16C1, 9F1, 11B1, and 11F2) were expressed using amber codon suppression to incorporate tyrosine sulfation. The sulfated variant of 16C1 demonstrated significantly improved chemokine binding compared to the non-sulfated counterpart, while the other nanobodies displayed equipotent or reduced affinity upon sulfation. The ability of tyrosine sulfation to modulate chemokine binding, both positively and negatively, could be leveraged for chemokine-targeted sulfo-nanobody therapeutics in the future.


Assuntos
Quimiocinas , Anticorpos de Domínio Único , Tirosina , Tirosina/metabolismo , Tirosina/química , Tirosina/análogos & derivados , Anticorpos de Domínio Único/química , Anticorpos de Domínio Único/metabolismo , Quimiocinas/metabolismo , Quimiocinas/química , Humanos , Ligação Proteica , Sulfatos/metabolismo , Sulfatos/química
14.
Nano Lett ; 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38847791

RESUMO

This work reports in situ (active) electrochemical control over the coupling strength between semiconducting nanoplatelets and a plasmonic cavity. We found that by applying a reductive bias to an Al nanoparticle lattice working electrode the number of CdSe nanoplatelet emitters that can couple to the cavity is decreased. Strong coupling can be reversibly recovered by discharging the lattice at oxidative potentials relative to the conduction band edge reduction potential of the emitters. By correlating the number of electrons added or removed with the measured coupling strength, we identified that loss and recovery of strong coupling are likely hindered by side processes that trap and/or inhibit electrons from populating the nanoplatelet conduction band. These findings demonstrate tunable, external control of strong coupling and offer prospects to tune selectivity in chemical reactions.

16.
Biology (Basel) ; 13(6)2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38927256

RESUMO

Increased intake of dietary antioxidants such as anthocyanins, which are enriched in colourful fruits, is a promising alternative to reduce the risk of degenerative diseases such as Alzheimer's Disease (AD). Since Amyloid ß (Aß) is one of the key components contributing to AD pathology, probably by reactive oxygen species (ROS) induction, this study investigated the preventive effect of anthocyanin-rich bilberry extract (BE) and its anthocyanin fraction (ACN) on ROS generation and cell toxicity. The results showed a significant and concentration-dependent decrease in neuroblastoma cell (SH-SY5Y) viability by BE or ACN, whereas no cell toxicity was observed in HeLa cells. Incubation with BE and ACN for 24 h diminished the generation of induced ROS levels in SH-SY5Y and HeLa cells. In addition, low concentrations of BE (1-5 µg/mL) showed protective effects against Aß-induced cytotoxicity in SH-SY5Y cells. In conclusion, our results suggest antioxidant and protective effects of BE and ACN, which could potentially be used to delay the course of neurodegenerative diseases such as AD. Further studies are needed to clarify the high potential of anthocyanins and their in vivo metabolites on neuronal function.

17.
Nano Lett ; 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38833415

RESUMO

We implement circuit quantum electrodynamics (cQED) with quantum dots in bilayer graphene, a maturing material platform that can host long-lived spin and valley states. Our device combines a high-impedance (Zr ≈ 1 kΩ) superconducting microwave resonator with a double quantum dot electrostatically defined in a graphene-based van der Waals heterostructure. Electric dipole coupling between the subsystems allows the resonator to sense the electric susceptibility of the double quantum dot from which we reconstruct its charge stability diagram. We achieve sensitive and fast detection of the interdot transition with a signal-to-noise ratio of 3.5 within 1 µs integration time. The charge-photon interaction is quantified in the dispersive and resonant regimes by comparing the resonator response to input-output theory, yielding a coupling strength of g/2π = 49.7 MHz. Our results introduce cQED as a probe for quantum dots in van der Waals materials and indicate a path toward coherent charge-photon coupling with bilayer graphene quantum dots.

18.
Oncologist ; 29(7): e918-e921, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38739017

RESUMO

Prescription drug costs within oncology remain a challenge for many patients with cancer. The Mark Cuban Cost Plus Drug Company (MCCPDC) launched in 2022, aiming to provide transparently priced medications at reduced costs. In this study, we sought to describe the potential impact of MCCPDC on Medicare Part-D oncology spending related to cancer-directed (n = 7) and supportive care (n = 26) drugs. We extracted data for drug-specific Part-D claims and spending for 2021. Using 90-count purchases from MCCPDC, we found potential Part-D savings of $857.8 million (91% savings) across the 7 cancer-directed drugs and $28.7 million (67% savings) across 21/26 (5/26 did not demonstrate savings) supportive care drugs. Collectively, our findings support that alternative purchasing models like MCCPDC may promote substantial health care savings.


Assuntos
Antineoplásicos , Medicare Part D , Neoplasias , Medicamentos sob Prescrição , Medicamentos sob Prescrição/economia , Antineoplásicos/economia , Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Redução de Custos
19.
Chemistry ; 30(38): e202400988, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38712638

RESUMO

The structure of the sidechain crosslinked Tyr-Leu-Trp peptide produced by the biarylitide crosslinking cytochrome P450Blt from Micromonospora sp. MW-13 has been reanalysed by a series of NMR, computational and isotope labelling experiments and shown to contain a C-N rather than a C-O bond. Additional in vivo experiments using such a modified peptide show there is a general tolerance of biarylitide crosslinking P450 enzymes for histidine to tryptophan mutations within their minimal peptide substrate sequences despite the lack of such residues noted in natural biarylitide gene clusters. This work further highlights the impressive ability of P450s from biarylitide biosynthesis pathways to act as biocatalysts for the formation of a range of sidechain crosslinked tripeptides.


Assuntos
Sistema Enzimático do Citocromo P-450 , Peptídeos Cíclicos , Triptofano , Triptofano/química , Triptofano/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Sistema Enzimático do Citocromo P-450/química , Peptídeos Cíclicos/química , Micromonospora/química , Micromonospora/metabolismo , Reagentes de Ligações Cruzadas/química , Biocatálise
20.
Chemistry ; 30(44): e202401606, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-38801240

RESUMO

The development of novel antivirals is crucial not only for managing current COVID-19 infections but for addressing potential future zoonotic outbreaks. SARS-CoV-2 main protease (Mpro) is vital for viral replication and viability and therefore serves as an attractive target for antiviral intervention. Herein, we report the optimization of a cyclic peptide inhibitor that emerged from an mRNA display selection against the SARS-CoV-2 Mpro to enhance its cell permeability and in vitro antiviral activity. By identifying mutation-tolerant amino acid residues within the peptide sequence, we describe the development of a second-generation Mpro inhibitor bearing five cyclohexylalanine residues. This cyclic peptide analogue exhibited significantly improved cell permeability and antiviral activity compared to the parent peptide. This approach highlights the importance of optimizing cyclic peptide hits for activity against intracellular targets such as the SARS-CoV-2 Mpro.


Assuntos
Antivirais , Proteases 3C de Coronavírus , Interações Hidrofóbicas e Hidrofílicas , Peptídeos Cíclicos , SARS-CoV-2 , Peptídeos Cíclicos/química , Peptídeos Cíclicos/farmacologia , Antivirais/química , Antivirais/farmacologia , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/enzimologia , Proteases 3C de Coronavírus/antagonistas & inibidores , Proteases 3C de Coronavírus/metabolismo , Proteases 3C de Coronavírus/química , Humanos , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Aminoácidos/química , Tratamento Farmacológico da COVID-19
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