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1.
CA Cancer J Clin ; 74(4): 359-367, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38685134

RESUMO

The American Joint Committee on Cancer (AJCC) staging system for all cancer sites, including gastroenteropancreatic neuroendocrine tumors (GEP-NETs), is meant to be dynamic, requiring periodic updates to optimize AJCC staging definitions. This entails the collaboration of experts charged with evaluating new evidence that supports changes to each staging system. GEP-NETs are the second most prevalent neoplasm of gastrointestinal origin after colorectal cancer. Since publication of the AJCC eighth edition, the World Health Organization has updated the classification and separates grade 3 GEP-NETs from poorly differentiated neuroendocrine carcinoma. In addition, because of major advancements in diagnostic and therapeutic technologies for GEP-NETs, AJCC version 9 advocates against the use of serum chromogranin A for the diagnosis and monitoring of GEP-NETs. Furthermore, AJCC version 9 recognizes the increasing role of endoscopy and endoscopic resection in the diagnosis and management of NETs, particularly in the stomach, duodenum, and colorectum. Finally, T1NXM0 has been added to stage I in these disease sites as well as in the appendix.


Assuntos
Neoplasias Intestinais , Estadiamento de Neoplasias , Tumores Neuroendócrinos , Neoplasias Pancreáticas , Neoplasias Gástricas , Humanos , Tumores Neuroendócrinos/patologia , Tumores Neuroendócrinos/diagnóstico , Tumores Neuroendócrinos/terapia , Estadiamento de Neoplasias/métodos , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/diagnóstico , Neoplasias Gástricas/patologia , Neoplasias Gástricas/diagnóstico , Neoplasias Intestinais/patologia , Neoplasias Intestinais/diagnóstico , Neoplasias Intestinais/terapia , Estados Unidos
2.
Nature ; 596(7873): 495-504, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34237771

RESUMO

There is a realistic expectation that the global effort in vaccination will bring the pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) under control. Nonetheless, uncertainties remain about the type of long-term association that the virus will establish with the human population and, in particular, whether coronavirus disease 2019 (COVID-19) will become an endemic disease. Although the trajectory is difficult to predict, the conditions, concepts and variables that influence this transition can be anticipated. Persistence of SARS-CoV-2 as an endemic virus, perhaps with seasonal epidemic peaks, may be fuelled by pockets of susceptible individuals and waning immunity after infection or vaccination, changes in the virus through antigenic drift that diminish protection and re-entries from zoonotic reservoirs. Here we review relevant observations from previous epidemics and discuss the potential evolution of SARS-CoV-2 as it adapts during persistent transmission in the presence of a level of population immunity. Lack of effective surveillance or adequate response could enable the emergence of new epidemic or pandemic patterns from an endemic infection of SARS-CoV-2. There are key pieces of data that are urgently needed in order to make good decisions; we outline these and propose a way forward.


Assuntos
COVID-19/epidemiologia , COVID-19/virologia , Pandemias , SARS-CoV-2/genética , SARS-CoV-2/patogenicidade , Animais , COVID-19/imunologia , COVID-19/transmissão , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/provisão & distribuição , Evolução Molecular , Humanos , Evasão da Resposta Imune , Programas de Imunização , Influenza Humana/imunologia , Influenza Humana/prevenção & controle , Influenza Humana/virologia , SARS-CoV-2/imunologia , Fatores de Tempo
3.
Development ; 150(18)2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37590085

RESUMO

Secondary lissencephaly evolved in mice due to effects on neurogenesis and the tangential distribution of neurons. Signaling pathways that help maintain lissencephaly are still poorly understood. We show that inactivating Twist1 in the primitive meninges causes cortical folding in mice. Cell proliferation in the meninges is reduced, causing loss of arachnoid fibroblasts that express Raldh2, an enzyme required for retinoic acid synthesis. Regionalized loss of Raldh2 in the dorsolateral meninges is first detected when folding begins. The ventricular zone expands and the forebrain lengthens at this time due to expansion of apical radial glia. As the cortex expands, regionalized differences in the levels of neurogenesis are coupled with changes to the tangential distribution of neurons. Consequentially, cortical growth at and adjacent to the midline accelerates with respect to more dorsolateral regions, resulting in cortical buckling and folding. Maternal retinoic acid supplementation suppresses cortical folding by normalizing forebrain length, neurogenesis and the tangential distribution of neurons. These results suggest that Twist1 and balanced retinoic acid signaling from the meninges are required to maintain normal levels of neurogenesis and lissencephaly in mice.


Assuntos
Lisencefalia , Tretinoína , Animais , Camundongos , Córtex Cerebral/metabolismo , Lisencefalia/metabolismo , Meninges , Neurogênese/genética , Neurônios/metabolismo , Tretinoína/metabolismo
4.
Development ; 149(1)2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34908123

RESUMO

Skull malformations are associated with vascular anomalies that can impair fluid balance in the central nervous system. We previously reported that humans with craniosynostosis and mutations in TWIST1 have dural venous sinus malformations. It is still unknown whether meningeal lymphatic networks, which are patterned alongside the venous sinuses, are also affected. We now show that the growth and expansion of meningeal lymphatics are perturbed in Twist1 craniosynostosis models. Changes to the local meningeal environment, including hypoplastic dura and venous malformations, affect the ability of lymphatic networks to sprout and remodel. Dorsal networks along the transverse sinus are hypoplastic with reduced branching. By contrast, basal networks closer to the skull base are more variably affected, showing exuberant growth in some animals, suggesting they are compensating for vessel loss in dorsal networks. Injecting a molecular tracer into cerebrospinal fluid reveals significantly less drainage to the deep cervical lymph nodes, which is indicative of impaired lymphatic function. Collectively, our results show that meningeal lymphatic networks are affected in craniosynostosis, suggesting that the clearance of ß-amyloid and waste from the central nervous system may be impeded.


Assuntos
Craniossinostoses/patologia , Vasos Linfáticos/anormalidades , Meninges/irrigação sanguínea , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Animais , Craniossinostoses/líquido cefalorraquidiano , Craniossinostoses/genética , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Repressoras/genética , Proteína 1 Relacionada a Twist/genética
5.
Development ; 149(22)2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36408946

RESUMO

Craniofacial development requires precise spatiotemporal regulation of multiple signaling pathways that crosstalk to coordinate the growth and patterning of the skull with surrounding tissues. Recent insights into these signaling pathways and previously uncharacterized progenitor cell populations have refined our understanding of skull patterning, bone mineralization and tissue homeostasis. Here, we touch upon classical studies and recent advances with an emphasis on developmental and signaling mechanisms that regulate the osteoblast lineage for the calvaria, which forms the roof of the skull. We highlight studies that illustrate the roles of osteoprogenitor cells and cranial suture-derived stem cells for proper calvarial growth and homeostasis. We also discuss genes and signaling pathways that control suture patency and highlight how perturbing the molecular regulation of these pathways leads to craniosynostosis. Finally, we discuss the recently discovered tissue and signaling interactions that integrate skull and cerebrovascular development, and the potential implications for both cerebrospinal fluid hydrodynamics and brain waste clearance in craniosynostosis.


Assuntos
Craniossinostoses , Crânio , Humanos , Crânio/metabolismo , Suturas Cranianas/metabolismo , Craniossinostoses/genética , Craniossinostoses/metabolismo , Homeostase , Transdução de Sinais
6.
N Engl J Med ; 385(21): 1941-1950, 2021 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-34706189

RESUMO

BACKGROUND: Coronavirus disease 2019 (Covid-19) disproportionately results in hospitalization or death in older patients and those with underlying conditions. Sotrovimab is a pan-sarbecovirus monoclonal antibody that was designed to prevent progression of Covid-19 in high-risk patients early in the course of disease. METHODS: In this ongoing, multicenter, double-blind, phase 3 trial, we randomly assigned, in a 1:1 ratio, nonhospitalized patients with symptomatic Covid-19 (≤5 days after the onset of symptoms) and at least one risk factor for disease progression to receive a single infusion of sotrovimab at a dose of 500 mg or placebo. The primary efficacy outcome was hospitalization (for >24 hours) for any cause or death within 29 days after randomization. RESULTS: In this prespecified interim analysis, which included an intention-to-treat population of 583 patients (291 in the sotrovimab group and 292 in the placebo group), 3 patients (1%) in the sotrovimab group, as compared with 21 patients (7%) in the placebo group, had disease progression leading to hospitalization or death (relative risk reduction, 85%; 97.24% confidence interval, 44 to 96; P = 0.002). In the placebo group, 5 patients were admitted to the intensive care unit, including 1 who died by day 29. Safety was assessed in 868 patients (430 in the sotrovimab group and 438 in the placebo group). Adverse events were reported by 17% of the patients in the sotrovimab group and 19% of those in the placebo group; serious adverse events were less common with sotrovimab than with placebo (in 2% and 6% of the patients, respectively). CONCLUSIONS: Among high-risk patients with mild-to-moderate Covid-19, sotrovimab reduced the risk of disease progression. No safety signals were identified. (Funded by Vir Biotechnology and GlaxoSmithKline; COMET-ICE ClinicalTrials.gov number, NCT04545060.).


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Neutralizantes/uso terapêutico , Tratamento Farmacológico da COVID-19 , Progressão da Doença , SARS-CoV-2/imunologia , Adulto , Idoso , Assistência Ambulatorial , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Neutralizantes/efeitos adversos , Método Duplo-Cego , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Incidência , Infusões Intravenosas , Análise de Intenção de Tratamento , Tempo de Internação , Masculino , Pessoa de Meia-Idade
7.
Plant Physiol ; 191(1): 142-160, 2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-36250895

RESUMO

The Plant-Conserved Region (P-CR) and the Class-Specific Region (CSR) are two plant-unique sequences in the catalytic core of cellulose synthases (CESAs) for which specific functions have not been established. Here, we used site-directed mutagenesis to replace amino acids and motifs within these sequences predicted to be essential for assembly and function of CESAs. We developed an in vivo method to determine the ability of mutated CesA1 transgenes to complement an Arabidopsis (Arabidopsis thaliana) temperature-sensitive root-swelling1 (rsw1) mutant. Replacement of a Cys residue in the CSR, which blocks dimerization in vitro, rendered the AtCesA1 transgene unable to complement the rsw1 mutation. Examination of the CSR sequences from 33 diverse angiosperm species showed domains of high-sequence conservation in a class-specific manner but with variation in the degrees of disorder, indicating a nonredundant role of the CSR structures in different CESA isoform classes. The Cys residue essential for dimerization was not always located in domains of intrinsic disorder. Expression of AtCesA1 transgene constructs, in which Pro417 and Arg453 were substituted for Ala or Lys in the coiled-coil of the P-CR, were also unable to complement the rsw1 mutation. Despite an expected role for Arg457 in trimerization of CESA proteins, AtCesA1 transgenes with Arg457Ala mutations were able to fully restore the wild-type phenotype in rsw1. Our data support that Cys662 within the CSR and Pro417 and Arg453 within the P-CR of Arabidopsis CESA1 are essential residues for functional synthase complex formation, but our data do not support a specific role for Arg457 in trimerization in native CESA complexes.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Aminoácidos Essenciais/genética , Aminoácidos Essenciais/metabolismo , Mutação , Celulose/metabolismo , Glucosiltransferases/metabolismo
8.
J Cardiovasc Electrophysiol ; 35(6): 1185-1195, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38591763

RESUMO

INTRODUCTION: Biventricular pacing (BiVp) improves outcomes in systolic heart failure patients with electrical dyssynchrony. BiVp is delivered from epicardial left ventricular (LV) and endocardial right ventricular (RV) electrodes. Acute electrical activation changes with different LV-RV stimulation offsets can help guide individually optimized BiVp programming. We sought to study the BiVp ventricular activation with different LV-RV offsets and compare with 12-lead ECG. METHODS: In five patients with BiVp (63 ± 17-year-old, 80% male, LV ejection fraction 27 ± 6%), we evaluated acute ventricular epicardial activation, varying LV-RV offsets in 20 ms increments from -40 to 80 ms, using electrocardiographic imaging (ECGI) to obtain absolute ventricular electrical uncoupling (VEUabs, absolute difference in average LV and average RV activation time) and total activation time (TAT). For each patient, we calculated the correlation between ECGI and corresponding ECG (3D-QRS-area and QRS duration) with different LV-RV offsets. RESULTS: The LV-RV offset to attain minimum VEUabs in individual patients ranged 20-60 ms. In all patients, a larger LV-RV offset was required to achieve minimum VEUabs (36 ± 17 ms) or 3D-QRS-area (40 ± 14 ms) than that for minimum TAT (-4 ± 9 ms) or QRS duration (-8 ± 11 ms). In individual patients, 3D-QRS-area correlated with VEUabs (r 0.65 ± 0.24) and QRS duration correlated with TAT (r 0.95 ± 0.02). Minimum VEUabs and minimum 3D-QRS-area were obtained by LV-RV offset within 20 ms of each other in all five patients. CONCLUSIONS: LV-RV electrical uncoupling, as assessed by ECGI, can be minimized by optimizing LV-RV stimulation offset. 3D-QRS-area is a surrogate to identify LV-RV offset that minimizes LV-RV uncoupling.


Assuntos
Potenciais de Ação , Terapia de Ressincronização Cardíaca , Eletrocardiografia , Valor Preditivo dos Testes , Função Ventricular Esquerda , Função Ventricular Direita , Humanos , Masculino , Projetos Piloto , Feminino , Pessoa de Meia-Idade , Idoso , Resultado do Tratamento , Frequência Cardíaca , Fatores de Tempo , Volume Sistólico , Ventrículos do Coração/fisiopatologia , Ventrículos do Coração/diagnóstico por imagem
9.
Chemistry ; 30(2): e202202760, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-37955851

RESUMO

The crystal structures of 4 ligand-rotational isomers of Au25 (PET)18 are presented. Two new ligand-rotational isomers are revealed, and two higher-quality structures (allowing complete solution of the ligand shell) of previously solved Au25 (PET)18 clusters are also presented. One of the structures lacks an inversion center, making it the first chiral Au25 (SR)18 structure solved. These structures combined with previously published Au25 (SR)18 structures enable an analysis of the empirical ligand conformation landscape for Au25 (SR)18 clusters. This analysis shows that the dihedral angles within the PET ligand are restricted to certain observable values, and also that the dihedral angle values are interdependent, in a manner reminiscent of biomolecule dihedral angles such as those in proteins and DNA. The influence of ligand conformational isomerism on optical and electronic properties was calculated, revealing that the ligand conformations affect the nanocluster absorption spectrum, which potentially provides a way to distinguish between isomers at low temperature.

10.
Cell Mol Life Sci ; 80(11): 332, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37872442

RESUMO

Meningeal lymphatic vessels (MLVs) help maintain central nervous system (CNS) homeostasis via their ability to facilitate macromolecule waste clearance and neuroimmune trafficking. Although these vessels were overlooked for centuries, they have now been characterized in humans, non-human primates, and rodents. Recent studies in mice have explored the stereotyped growth and expansion of MLVs in dura mater, the various transcriptional, signaling, and environmental factors regulating their development and long-term maintenance, and the pathological changes these vessels undergo in injury, disease, or with aging. Key insights gained from these studies have also been leveraged to develop therapeutic approaches that help augment or restore MLV functions to improve brain health and cognition. Here, we review fundamental processes that control the development of peripheral lymphatic networks and how these might apply to the growth and expansion of MLVs in their unique meningeal environment. We also emphasize key findings in injury and disease models that may reveal additional insights into the plasticity of these vessels throughout the lifespan. Finally, we highlight unanswered questions and future areas of study that can further reveal the exciting therapeutic potential of meningeal lymphatics.


Assuntos
Vasos Linfáticos , Camundongos , Animais , Vasos Linfáticos/patologia , Meninges/fisiologia , Sistema Nervoso Central , Sistema Linfático , Modelos Animais
11.
Plant Dis ; 108(3): 666-670, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37807093

RESUMO

Green mold (Trichoderma aggressivum) is an invasive disease of commercial mushrooms introduced into the United States from Europe that now has spread to commercial mushrooms throughout North America. We examined potential sources of invasive green mold inoculum and the association with different compost filling technologies on a large actively producing commercial mushroom farm. Green mold foci were sampled bed by bed, which generated 20,906 data points. Logistic regression was used to determine treatment differences. Mechanical filling of compost into the beds reduced green mold incidence over hand filling, apparently due to the reduced incidence of worker contact with the floor and between beds. Lower growing beds located closer to the floor had a higher incidence of green mold for both mechanical and hand-filled beds. We conclude that mechanical filling and generally reducing contact with the floor and between beds will reduce spread of green mold in commercial mushroom production.


Assuntos
Agaricus , Compostagem , Trichoderma , Estados Unidos , Incidência , Europa (Continente)
12.
J Appl Clin Med Phys ; 25(3): e14304, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38368615

RESUMO

BACKGROUND: Artifacts from implantable cardioverter defibrillators (ICDs) are a challenge to magnetic resonance imaging (MRI)-guided radiotherapy (MRgRT). PURPOSE: This study tested an unsupervised generative adversarial network to mitigate ICD artifacts in balanced steady-state free precession (bSSFP) cine MRIs and improve image quality and tracking performance for MRgRT. METHODS: Fourteen healthy volunteers (Group A) were scanned on a 0.35 T MRI-Linac with and without an MR conditional ICD taped to their left pectoral to simulate an implanted ICD. bSSFP MRI data from 12 of the volunteers were used to train a CycleGAN model to reduce ICD artifacts. The data from the remaining two volunteers were used for testing. In addition, the dataset was reorganized three times using a Leave-One-Out scheme. Tracking metrics [Dice similarity coefficient (DSC), target registration error (TRE), and 95 percentile Hausdorff distance (95% HD)] were evaluated for whole-heart contours. Image quality metrics [normalized root mean square error (nRMSE), peak signal-to-noise ratio (PSNR), and multiscale structural similarity (MS-SSIM) scores] were evaluated. The technique was also tested qualitatively on three additional ICD datasets (Group B) including a patient with an implanted ICD. RESULTS: For the whole-heart contour with CycleGAN reconstruction: 1) Mean DSC rose from 0.910 to 0.935; 2) Mean TRE dropped from 4.488 to 2.877 mm; and 3) Mean 95% HD dropped from 10.236 to 7.700 mm. For the whole-body slice with CycleGAN reconstruction: 1) Mean nRMSE dropped from 0.644 to 0.420; 2) Mean MS-SSIM rose from 0.779 to 0.819; and 3) Mean PSNR rose from 18.744 to 22.368. The three Group B datasets evaluated qualitatively displayed a reduction in ICD artifacts in the heart. CONCLUSION: CycleGAN-generated reconstructions significantly improved both tracking and image quality metrics when used to mitigate artifacts from ICDs.


Assuntos
Aprendizado Profundo , Desfibriladores Implantáveis , Radioterapia Guiada por Imagem , Humanos , Artefatos , Imageamento por Ressonância Magnética/métodos , Processamento de Imagem Assistida por Computador/métodos
13.
Clin Diabetes ; 42(2): 232-242, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38694246

RESUMO

The authors trialed a mobile application, DiabetesXcel, which included type 2 diabetes-focused educational videos and modules, in 50 adults of Bronx, NY, a region with a high prevalence of diabetes and diabetes complications. From baseline to 4 months and from baseline to 6 months, there was significantly improved quality of life, self-management, knowledge, self-efficacy, depression, A1C, and LDL cholesterol among those who used DiabetesXcel. There was also a significant decrease in diabetes-related emergency department visits and hospital admissions from baseline to 6 months. This study demonstrates that DiabetesXcel could be beneficial for type 2 diabetes management.

14.
J Stroke Cerebrovasc Dis ; 33(3): 107557, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38198946

RESUMO

OBJECTIVES: Cerebral small vessel disease is a group of pathologies in which alterations of the brain's blood vessels contribute to stroke and neurocognitive changes. Recently, a neurotoxic waste clearance system composed of perivascular spaces abutting the brain's blood vessels, termed the glymphatic system, has been identified as a key player in brain homeostasis. Given that small vessel disease and the glymphatic system share anatomical structures, this review aims to reexamine small vessel disease in the context of the glymphatic system and highlight novel aspects of small vessel disease physiology. MATERIALS AND METHODS: This review was conducted with an emphasis on studies that examined aspects of small vessel disease and on works characterizing the glymphatic system. We searched PubMed for relevant articles using the following keywords: glymphatics, cerebral small vessel disease, arterial pulsatility, hypertension, blood-brain barrier, endothelial dysfunction, stroke, diabetes. RESULTS: Cerebral small vessel disease and glymphatic dysfunction are anatomically connected and significant risk factors are shared between the two. These include hypertension, type 2 diabetes, advanced age, poor sleep, obesity, and neuroinflammation. There is clear evidence that CSVD hinders the effective functioning of glymphatic system. CONCLUSION: These shared risk factors, as well as the model of cerebral amyloid angiopathy pathogenesis, hint at the possibility that glymphatic dysfunction could independently contribute to the pathogenesis of cerebral small vessel disease. However, the current evidence supports a model of cascading dysfunction, wherein concurrent small vessel and glymphatic injury hinder glymphatic-mediated recovery and promote the progression of subclinical to clinical disease.


Assuntos
Doenças de Pequenos Vasos Cerebrais , Diabetes Mellitus Tipo 2 , Sistema Glinfático , Hipertensão , Acidente Vascular Cerebral , Humanos , Sistema Glinfático/fisiologia , Encéfalo , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Doenças de Pequenos Vasos Cerebrais/etiologia , Hipertensão/complicações
15.
J Am Chem Soc ; 145(10): 5855-5863, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36854118

RESUMO

Cationic cyclopropanation involves the γ-elimination at carbocations to form a new σ-C-C bond through proton loss. While exceedingly rare in bulk solution, it is recognized as one of the main biosynthetic cyclopropanation pathways. Despite the rich history of bioinspired synthetic chemistry, cationic cyclopropanation has not been appropriated for the synthetic toolbox, likely due to the preference of carbocations to undergo competing E1 ß-elimination pathways. Here, we present an in-depth synthetic and computational study of cationic cyclopropanation, focusing on the 6,8-cycloeudesmanes as a platform for this investigation. We were able to apply biomimetic cationic cyclopropanation to the synthesis of several 6,8-cycloeudesmanes and non-natural analogues─in doing so, we showcase the power of this transformation in the preparation of complex cyclopropanes.

16.
Mol Microbiol ; 117(4): 937-957, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35072315

RESUMO

Pseudomonas aeruginosa is a significant opportunistic pathogen responsible for numerous human infections. Its high pathogenicity resides in a diverse array of virulence factors and an ability to adapt to hostile environments. We report that these factors are tied to the activity of condensins, SMC and MksBEF, which primarily function in structural chromosome maintenance. This study revealed that both proteins are required for P. aeruginosa virulence during corneal infection. The reduction in virulence was traced to broad changes in gene expression. Transcriptional signatures of smc and mksB mutants were largely dissimilar and non-additive, with the double mutant displaying a distinct gene expression profile. Affected regulons included those responsible for lifestyle control, primary metabolism, surface adhesion and biofilm growth, iron and sulfur assimilation, and numerous virulence factors, including type 3 and type 6 secretion systems. The in vitro phenotypes of condensin mutants mirrored their transcriptional profiles and included impaired production and secretion of multiple virulence factors, growth deficiencies under nutrient limiting conditions, and altered c-di-GMP signaling. Notably, c-di-GMP mediated some but not all transcriptional responses of the mutants. Thus, condensins are integrated into the control of multiple genetic programs related to epigenetic and virulent behavior of P. aeruginosa.


Assuntos
Infecções por Pseudomonas , Pseudomonas aeruginosa , Adenosina Trifosfatases , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biofilmes , Proteínas de Ligação a DNA , Regulação Bacteriana da Expressão Gênica , Humanos , Estilo de Vida , Complexos Multiproteicos , Pseudomonas aeruginosa/metabolismo , Virulência/genética , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
17.
J Hepatol ; 79(4): 924-932, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37290591

RESUMO

BACKGROUND & AIMS: Current therapy for chronic hepatitis B virus (cHBV) infection involves lifelong treatment. New treatments that enable HBV functional cure would represent a clinically meaningful advance. ALN-HBV and VIR-2218 are investigational RNA interference therapeutics that target all major HBV transcripts. METHODS: We report on: i) the safety of single doses of VIR-2218 (modified from ALN-HBV by enhanced stabilization chemistry plus technology to reduce off-target, seed-mediated binding while maintaining on-target antiviral activity) and ALN-HBV in humanized mice; ii) a cross-study comparison of the safety of single doses of VIR-2218 and ALN-HBV in healthy human volunteers (n = 24 and n = 49, respectively); and iii) the antiviral activity of two doses of 20, 50, 100, 200 mg of VIR-2218 (total n = 24) vs. placebo (n = 8), given 4 weeks apart, in participants with cHBV infection. RESULTS: In humanized mice, alanine aminotransferase (ALT) levels were markedly lower following administration of VIR-2218 compared with ALN-HBV. In healthy volunteers, post-treatment ALT elevations occurred in 28% of participants receiving ALN-HBV compared with none in those receiving VIR-2218. In participants with cHBV infection, VIR-2218 was associated with dose-dependent reductions in hepatitis B surface antigen (HBsAg). The greatest mean reduction of HBsAg at Week 20 in participants receiving 200 mg was 1.65 log IU/ml. The HBsAg reduction was maintained at 0.87 log IU/ml at Week 48. No participants had serum HBsAg loss or hepatitis B surface antibody seroconversion. CONCLUSIONS: VIR-2218 demonstrated an encouraging hepatic safety profile in preclinical and clinical studies as well as dose-dependent HBsAg reductions in patients with cHBV infection. These data support future studies with VIR-2218 as part of combination regimens with a goal of HBV functional cure. TRIAL REGISTRATION: ClinicalTrials.gov identifiers: NCT02826018 and NCT03672188. IMPACT AND IMPLICATIONS: A significant unmet need exists for therapies for chronic HBV (cHBV) infection that achieve functional cure. We report clinical and non-clinical data on two investigational small-interfering RNAs that target HBx, ALN-HBV and VIR-2218, demonstrating that incorporation of enhanced stabilization chemistry plus technology in VIR-2218 reduces its propensity to cause ALT elevations relative to its parent compound, ALN-HBV. We also show that VIR-2218 reduces hepatitis B surface antigen levels in a dose-dependent manner in participants with cHBV infection. These studies support the continued development of VIR-2218 as part of therapeutic regimens for cHBV infection, with the goal of a functional cure, and are important for HBV researchers and physicians.


Assuntos
Hepatite B Crônica , Hepatite B , Humanos , Animais , Camundongos , Hepatite B Crônica/tratamento farmacológico , Vírus da Hepatite B , Antígenos de Superfície da Hepatite B , Terapêutica com RNAi , Ensaios Clínicos Controlados Aleatórios como Assunto , Antivirais , DNA Viral , Antígenos E da Hepatite B , Hepatite B/tratamento farmacológico
18.
Ann Surg ; 277(5): 721-726, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36052678

RESUMO

OBJECTIVE: Clinical predictors of pathological complete response have not reliably identified patients for whom an organ-sparing approach following neoadjuvant chemoradiation be undertaken for esophageal cancer patients. We sought to identify high-risk predictors of residual carcinoma that may preclude patients from a selective surgical approach. BACKGROUND: Patients treated with neoadjuvant chemoradiation followed by esophagectomy for esophageal adenocarcinoma were identified. PATIENTS AND METHODS: Correlation between clinical and pathologic complete responses were examined. Regression models and recursive partitioning were utilized to identify features associated with residual carcinoma. External validation of these high-risk factors was performed on a data set from an independent institution. RESULTS: A total of 326 patients were identified, in whom clinical complete response was noted in 104/326 (32%). Pathologic complete response was noted in only 33/104 (32%) of these clinical complete responders. Multivariable analysis identified that the presence of stricture ( P =0.011), positive biopsy ( P =0.010), and signet ring cell histology ( P =0.019) were associated with residual cancer. Recursive partitioning corroborated a 94% probability of residual disease, or greater, for each of these features. The positive predictive value was >90% for these characteristics. A SUV max >5.4 at the esophageal primary in the absence of esophagitis was also a high-risk factor for residual carcinoma. External validation confirmed these high-risk factors to be implicated in the finding of residual carcinoma. CONCLUSIONS: Clinical parameters of response are poor predictors of complete pathologic response leading to challenges in selecting candidates for active surveillance. However, we characterize several high-risk features for residual carcinoma which indicate that esophagectomy should not be delayed.


Assuntos
Adenocarcinoma , Neoplasias Esofágicas , Humanos , Terapia Neoadjuvante , Neoplasias Esofágicas/terapia , Neoplasias Esofágicas/patologia , Adenocarcinoma/terapia , Adenocarcinoma/patologia , Esofagectomia , Estudos Retrospectivos , Estadiamento de Neoplasias
19.
J Pediatr ; 263: 113650, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37536483

RESUMO

OBJECTIVES: To document the case-fatality rate (CFR) of congenital syphilis diagnosed by molecular tools and rabbit infectivity testing (RIT) of clinical specimens in addition to standard evaluation and to compare that with the CFR using the Centers for Disease Control and Prevention (CDC) surveillance case definition. STUDY DESIGN: Prospective, single site, cohort study of all cases of syphilis among mothers and their infants from 1984 to 2002. The diagnosis of congenital syphilis was determined using IgM immunoblotting, polymerase chain reaction, and RIT of fetal or infant specimens in addition to clinical, laboratory, and radiographic criteria. Data were retrospectively reviewed to ascertain fetal and neonatal mortality. RESULTS: During the 18-year study, there were 191 cases of congenital syphilis confirmed by abnormalities on clinical, laboratory, or radiographic evaluation and/or positive serum IgM immunoblot, blood polymerase chain reaction, or blood/cerebrospinal fluid RIT. Of the 191 cases, 59 died for a CFR of 31%. Of the 59 deaths, 53 (90%) were stillborn and 6 (10%) died in the neonatal period. The majority (74%, 39/53) of stillbirths occurred in the third trimester. The CDC surveillance case definition correctly identified all infants with congenital syphilis, but the CDC CFR was 10% which underestimated the CFR by more than 300%. CONCLUSIONS: Our findings corroborate the high sensitivity of the CDC surveillance definition for congenital syphilis but highlight its poor estimation of its associated mortality. The CFR among infected progeny of pregnant women with syphilis was 31%, due mostly to demise in the third trimester and as such highlights the need for detection and appropriate treatment of syphilis during pregnancy.


Assuntos
Complicações Infecciosas na Gravidez , Sífilis Congênita , Sífilis , Lactente , Animais , Humanos , Gravidez , Feminino , Coelhos , Sífilis Congênita/diagnóstico , Estudos de Coortes , Estudos Prospectivos , Estudos Retrospectivos , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/tratamento farmacológico , Imunoglobulina M
20.
Chemistry ; 29(31): e202300261, 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-36849870

RESUMO

Azide-enolate cycloaddition-rearrangements offer potential for rapid access to diverse molecular frameworks from simple precursors. We report here that investigations into the cycloadditions of ester or amide enolates with vinyl azides led to the identification of two reaction processes - direct α-amination of amides and lactams, and the synthesis of ene-γ-lactams from esters. The outcomes of these reactions depended on the fate of key vinyl triazoline intermediates generated in the initial cycloaddition step. Isolation of reaction intermediates in the ene-γ-lactam synthesis revealed the unexpected addition of two enolate equivalents, one of which is later eliminated. Computational studies further suggested an unusual reaction pathway involving direct addition of an enolate to the terminal carbon of the N-vinyl triazoline. In contrast, the α-amination of amides and lactams proceeded by rearrangement of the intermediate triazoline to give an imine, hydrolysis or reduction of which gave access to primary or secondary α-amino amides or lactams.

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