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1.
Chem Rev ; 124(9): 6078-6144, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38630862

RESUMO

Alcohols are abundant and attractive feedstock molecules for organic synthesis. Many methods for their functionalization require them to first be converted into a more activated derivative, while recent years have seen a vast increase in the number of complexity-building transformations that directly harness unprotected alcohols. This Review discusses how transition metal catalysis can be used toward this goal. These transformations are broadly classified into three categories. Deoxygenative functionalizations, representing derivatization of the C-O bond, enable the alcohol to act as a leaving group toward the formation of new C-C bonds. Etherifications, characterized by derivatization of the O-H bond, represent classical reactivity that has been modernized to include mild reaction conditions, diverse reaction partners, and high selectivities. Lastly, chain functionalization reactions are described, wherein the alcohol group acts as a mediator in formal C-H functionalization reactions of the alkyl backbone. Each of these three classes of transformation will be discussed in context of intermolecular arylation, alkylation, and related reactions, illustrating how catalysis can enable alcohols to be directly harnessed for organic synthesis.

2.
JAMA ; 329(4): 318-324, 2023 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-36692560

RESUMO

Importance: VEXAS (vacuoles, E1-ubiquitin-activating enzyme, X-linked, autoinflammatory, somatic) syndrome is a disease with rheumatologic and hematologic features caused by somatic variants in UBA1. Pathogenic variants are associated with a broad spectrum of clinical manifestations. Knowledge of prevalence, penetrance, and clinical characteristics of this disease have been limited by ascertainment biases based on known phenotypes. Objective: To determine the prevalence of pathogenic variants in UBA1 and associated clinical manifestations in an unselected population using a genomic ascertainment approach. Design, Setting, and Participants: This retrospective observational study evaluated UBA1 variants in exome data from 163 096 participants within the Geisinger MyCode Community Health Initiative. Clinical phenotypes were determined from Geisinger electronic health record data from January 1, 1996, to January 1, 2022. Exposures: Exome sequencing was performed. Main Outcomes and Measures: Outcome measures included prevalence of somatic UBA1 variation; presence of rheumatologic, hematologic, pulmonary, dermatologic, and other findings in individuals with somatic UBA1 variation on review of the electronic health record; review of laboratory data; bone marrow biopsy pathology analysis; and in vitro enzymatic assays. Results: In 163 096 participants (mean age, 52.8 years; 94% White; 61% women), 11 individuals harbored likely somatic variants at known pathogenic UBA1 positions, with 11 of 11 (100%) having clinical manifestations consistent with VEXAS syndrome (9 male, 2 female). A total of 5 of 11 individuals (45%) did not meet criteria for rheumatologic and/or hematologic diagnoses previously associated with VEXAS syndrome; however, all individuals had anemia (hemoglobin: mean, 7.8 g/dL; median, 7.5 g/dL), which was mostly macrocytic (10/11 [91%]) with concomitant thrombocytopenia (10/11 [91%]). Among the 11 patients identified, there was a pathogenic variant in 1 male participant prior to onset of VEXAS-related signs or symptoms and 2 female participants had disease with heterozygous variants. A previously unreported UBA1 variant (c.1861A>T; p.Ser621Cys) was found in a symptomatic patient, with in vitro data supporting a catalytic defect and pathogenicity. Together, disease-causing UBA1 variants were found in 1 in 13 591 unrelated individuals (95% CI, 1:7775-1:23 758), 1 in 4269 men older than 50 years (95% CI, 1:2319-1:7859), and 1 in 26 238 women older than 50 years (95% CI, 1:7196-1:147 669). Conclusions and Relevance: This study provides an estimate of the prevalence and a description of the clinical manifestations of UBA1 variants associated with VEXAS syndrome within a single regional health system in the US. Additional studies are needed in unselected and genetically diverse populations to better define general population prevalence and phenotypic spectrum.


Assuntos
Síndromes Mielodisplásicas , Dermatopatias Genéticas , Enzimas Ativadoras de Ubiquitina , Feminino , Humanos , Masculino , Biópsia , Registros Eletrônicos de Saúde , Prevalência , Síndromes Mielodisplásicas/complicações , Síndromes Mielodisplásicas/diagnóstico , Síndromes Mielodisplásicas/epidemiologia , Síndromes Mielodisplásicas/genética , Enzimas Ativadoras de Ubiquitina/genética , Mutação , Estudos Retrospectivos , Exoma , Pessoa de Meia-Idade , Dermatopatias Genéticas/complicações , Dermatopatias Genéticas/diagnóstico , Dermatopatias Genéticas/epidemiologia , Dermatopatias Genéticas/genética , Estados Unidos/epidemiologia
3.
Dev Biol ; 455(1): 60-72, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31279726

RESUMO

Salamanders are capable of full-thickness skin regeneration where removal of epidermis, dermis and hypodermis results in scar-free repair. What remains unclear is whether regeneration of these tissues recapitulates the cellular events of skin development or occurs through a process unique to regenerative healing. Unfortunately, information on the post-embryonic development of salamander skin is severely lacking, having focused on compartments or cell types, but never on the skin as a complete organ. By examining coordinated development of the epidermis and dermis in axolotls we establish six distinct stages of skin development (I-VI): I-V for normally paedomorphic adults and a sixth stage following metamorphosis. Raising animals either in isolation (zero density pressure) or in groups (density pressure) we find that skin development progresses as a function of animal size and that density directly effects developmental rate. Using keratins, p63, and proliferative markers, we show that when the dermis transforms into the stratum spongiosum and stratum compactum, keratinocytes differentiate into at least three distinct phenotypes that reveal a cryptic stratification program uncoupled from metamorphosis. Lastly, comparing skin regeneration to skin development, we find that dermal regeneration occurs through a unique process, relying heavily on remodeling of the wound extracellular matrix, rather than proceeding through direct development of a dermal lamella produced by the epidermis. By preventing fibroblast influx into the wound bed using beryllium nitrate, we show that in the absence of fibroblast generated ECM production skin regeneration occurs through an alternate route that recapitulates development.


Assuntos
Desenvolvimento Embrionário/fisiologia , Fibroblastos/fisiologia , Regeneração/fisiologia , Transdução de Sinais/fisiologia , Pele/fisiopatologia , Cicatrização/fisiologia , Ambystoma mexicanum/embriologia , Ambystoma mexicanum/fisiologia , Animais , Derme/embriologia , Derme/metabolismo , Derme/fisiologia , Epiderme/embriologia , Epiderme/metabolismo , Epiderme/fisiologia , Matriz Extracelular/metabolismo , Matriz Extracelular/fisiologia , Queratinócitos/citologia , Queratinócitos/metabolismo , Queratinócitos/fisiologia , Queratinas/metabolismo , Masculino , Pele/embriologia , Pele/lesões , Fatores de Tempo
4.
J Am Chem Soc ; 142(18): 8109-8115, 2020 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-32319766

RESUMO

We report a one-step procedure to directly reduce unactivated aryl esters into their corresponding tolyl derivatives. This is achieved by an organosilane-mediated ester hydrosilylation reaction and subsequent Ni/NHC-catalyzed hydrogenolysis. The resulting conditions provide a direct and efficient alternative to multi-step procedures for this transformation that often require the use of hazardous metal hydrides. Applications in the synthesis of -CD3-containing products, derivatization of bioactive molecules, and chemoselective reduction in the presence of other C-O bonds are demonstrated.

5.
Immunol Cell Biol ; 98(2): 93-113, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31698518

RESUMO

T lymphocytes utilize amoeboid migration to navigate effectively within complex microenvironments. The precise rearrangement of the actin cytoskeleton required for cellular forward propulsion is mediated by actin regulators, including the actin-related protein 2/3 (Arp2/3) complex, a macromolecular machine that nucleates branched actin filaments at the leading edge. The consequences of modulating Arp2/3 activity on the biophysical properties of the actomyosin cortex and downstream T cell function are incompletely understood. We report that even a moderate decrease of Arp3 levels in T cells profoundly affects actin cortex integrity. Reduction in total F-actin content leads to reduced cortical tension and disrupted lamellipodia formation. Instead, in Arp3-knockdown cells, the motility mode is dominated by blebbing migration characterized by transient, balloon-like protrusions at the leading edge. Although this migration mode seems to be compatible with interstitial migration in three-dimensional environments, diminished locomotion kinetics and impaired cytotoxicity interfere with optimal T cell function. These findings define the importance of finely tuned, Arp2/3-dependent mechanophysical membrane integrity in cytotoxic effector T lymphocyte activities.


Assuntos
Citoesqueleto de Actina/metabolismo , Complexo 2-3 de Proteínas Relacionadas à Actina/metabolismo , Proteína 3 Relacionada a Actina/metabolismo , Movimento Celular/genética , Linfócitos T Citotóxicos/metabolismo , Complexo 2-3 de Proteínas Relacionadas à Actina/genética , Proteína 3 Relacionada a Actina/genética , Actinas/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células/genética , Sobrevivência Celular/genética , Regulação para Baixo , Técnicas de Silenciamento de Genes , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , RNA Interferente Pequeno , Análise de Célula Única , Linfócitos T Citotóxicos/citologia , Peixe-Zebra
6.
Development ; 143(19): 3491-3505, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27578793

RESUMO

Epimorphic regeneration proceeds with or without formation of a blastema, as observed for the limb and skin, respectively. Inhibition of epimorphic regeneration provides a means to interrogate the cellular and molecular mechanisms that regulate it. In this study, we show that exposing amputated limbs to beryllium nitrate disrupts blastema formation and causes severe patterning defects in limb regeneration. In contrast, exposing full-thickness skin wounds to beryllium only causes a delay in skin regeneration. By transplanting full-thickness skin from ubiquitous GFP-expressing axolotls to wild-type hosts, we demonstrate that beryllium inhibits fibroblast migration during limb and skin regeneration in vivo Moreover, we show that beryllium also inhibits cell migration in vitro using axolotl and human fibroblasts. Interestingly, beryllium did not act as an immunostimulatory agent as it does in Anurans and mammals, nor did it affect keratinocyte migration, proliferation or re-epithelialization, suggesting that the effect of beryllium is cell type-specific. While we did not detect an increase in cell death during regeneration in response to beryllium, it did disrupt cell proliferation in mesenchymal cells. Taken together, our data show that normal blastema organogenesis cannot occur without timely infiltration of local fibroblasts and highlights the importance of positional information to instruct pattern formation during regeneration. In contrast, non-blastemal-based skin regeneration can occur despite early inhibition of fibroblast migration and cell proliferation.


Assuntos
Berílio/farmacologia , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Nitratos/farmacologia , Ambystoma mexicanum/fisiologia , Animais , Padronização Corporal/efeitos dos fármacos , Padronização Corporal/fisiologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Extremidades/fisiologia , Regeneração/efeitos dos fármacos , Regeneração/fisiologia
7.
Mol Cell ; 44(6): 918-27, 2011 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-22195965

RESUMO

Proper genome packaging requires coordination of both DNA and histone metabolism. While histone gene transcription and RNA processing adequately provide for scheduled needs, how histone supply adjusts to unexpected changes in demand remains unknown. Here, we reveal that the histone chaperone nuclear autoantigenic sperm protein (NASP) protects a reservoir of soluble histones H3-H4. The importance of NASP is revealed upon histone overload, engagement of the reservoir during acute replication stress, and perturbation of Asf1 activity. The reservoir can be fine-tuned, increasing or decreasing depending on the level of NASP. Our data suggest that NASP does so by balancing the activity of the heat shock proteins Hsc70 and Hsp90 to direct H3-H4 for degradation by chaperone-mediated autophagy. These insights into NASP function and the existence of a tunable reservoir in mammalian cells demonstrate that contingency is integrated into the histone supply chain to respond to unexpected changes in demand.


Assuntos
Autoantígenos/metabolismo , Histonas/metabolismo , Chaperonas Moleculares/metabolismo , Proteínas Nucleares/metabolismo , Autofagia , Células HEK293 , Células HeLa , Humanos , Solubilidade , Células Tumorais Cultivadas
8.
BMC Pediatr ; 18(1): 293, 2018 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-30180831

RESUMO

BACKGROUND: Economically disadvantaged families receive care in both clinical and community settings, but this care is rarely coordinated and can result in conflicting educational messaging. WEE Baby Care is a pragmatic randomized clinical trial evaluating a patient-centered responsive parenting (RP) intervention that uses health information technology (HIT) strategies to coordinate care between pediatric primary care providers (PCPs) and the Special Supplemental Nutrition Program for Women, Infant and Children (WIC) community nutritionists to prevent rapid weight gain from birth to 6 months. It is hypothesized that data integration and coordination will improve consistency in RP messaging and parent self-efficacy, promoting shared decision making and infant self-regulation, to reduce infant rapid weight gain from birth to 6 months. METHODS/DESIGN: Two hundred and ninety mothers and their full-term newborns will be recruited and randomized to the "RP intervention" or "standard care control" groups. The RP intervention includes: 1) parenting and nutrition education developed using the American Academy of Pediatrics Healthy Active Living for Families curriculum in conjunction with portions of a previously tested RP curriculum delivered by trained pediatric PCPs and WIC nutritionists during regularly scheduled appointments; 2) parent-reported data using the Early Healthy Lifestyles (EHL) risk assessment tool; and 3) data integration into child's electronic health records with display and documentation features to inform counseling and coordinate care between pediatric PCPs and WIC nutritionists. The primary study outcome is rapid infant weight gain from birth to 6 months derived from sex-specific World Health Organization adjusted weight-for-age z-scores. Additional outcomes include care coordination, messaging consistency, parenting behaviors (e.g., food to soothe), self-efficacy, and infant sleep health. Infant temperament and parent depression will be explored as moderators of RP effects on infant outcomes. DISCUSSION: This pragmatic patient-centered RP intervention integrates and coordinates care across clinical and community sectors, potentially offering a fundamental change in the delivery of pediatric care for prevention and health promotion. Findings from this trial can inform large scale dissemination of obesity prevention programs. TRIAL REGISTRATION: Restrospective Clinical Trial Registration: NCT03482908 . Registered March 29, 2018.


Assuntos
Aconselhamento , Mães/educação , Necessidades Nutricionais , Poder Familiar , Assistência Centrada no Paciente/organização & administração , Obesidade Infantil/prevenção & controle , Serviços de Saúde Comunitária/organização & administração , Tomada de Decisões , Feminino , Assistência Alimentar , Humanos , Lactente , Fenômenos Fisiológicos da Nutrição do Lactente , Recém-Nascido , Informática Médica , Pennsylvania , Ensaios Clínicos Pragmáticos como Assunto , Atenção Primária à Saúde/organização & administração , Autoeficácia , Aumento de Peso
9.
Arterioscler Thromb Vasc Biol ; 35(11): 2443-50, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26359513

RESUMO

OBJECTIVE: Lymphatic endothelial dysfunction underlies the pathogenesis of many chronic inflammatory disorders. The proinflammatory cytokine tumor necrosis factor (TNF) is known for its role in disrupting the function of the lymphatic vasculature. This study investigates the ability of apolipoprotein (apo) A-I, the principal apolipoprotein of high-density lipoproteins, to preserve the normal function of lymphatic endothelial cells treated with TNF. APPROACH AND RESULTS: TNF decreased the ability of lymphatic endothelial cells to form tube-like structures. Preincubation of lymphatic endothelial cells with apoA-I attenuated the TNF-mediated inhibition of tube formation in a concentration-dependent manner. In addition, apoA-I reversed the TNF-mediated suppression of lymphatic endothelial cell migration and lymphatic outgrowth in thoracic duct rings. ApoA-I also abrogated the negative effect of TNF on lymphatic neovascularization in an ATP-binding cassette transporter A1-dependent manner. At the molecular level, this involved downregulation of TNF receptor-1 and the conservation of prospero-related homeobox gene-1 expression, a master regulator of lymphangiogenesis. ApoA-I also re-established the normal phenotype of the lymphatic network in the diaphragms of human TNF transgenic mice. CONCLUSIONS: ApoA-I restores the neovascularization capacity of the lymphatic system during TNF-mediated inflammation. This study provides a proof-of-concept that high-density lipoprotein-based therapeutic strategies may attenuate chronic inflammation via its action on lymphatic vasculature.


Assuntos
Anti-Inflamatórios/farmacologia , Apolipoproteína A-I/farmacologia , Células Endoteliais/efeitos dos fármacos , Inflamação/prevenção & controle , Linfangiogênese/efeitos dos fármacos , Ducto Torácico/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologia , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Animais , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Proteínas de Homeodomínio/metabolismo , Humanos , Inflamação/metabolismo , Inflamação/patologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fenótipo , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Ducto Torácico/metabolismo , Ducto Torácico/patologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Proteínas Supressoras de Tumor/metabolismo
10.
Nat Struct Mol Biol ; 15(9): 972-9, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19172751

RESUMO

The heterochromatin protein 1 (HP1)-rich heterochromatin domains next to centromeres are crucial for chromosome segregation during mitosis. This mitotic function requires their faithful reproduction during the preceding S phase, a process whose mechanism and regulation are current puzzles. Here we show that p150, a subunit of chromatin assembly factor 1, has a key role in the replication of pericentric heterochromatin and S-phase progression in mouse cells, independently of its known function in histone deposition. By a combination of depletion and complementation assays in vivo, we link this unique function of p150 to its ability to interact with HP1. Absence of this functional interaction triggers S-phase arrest at the time of replication of pericentromeric heterochromatin, without eliciting known DNA-based checkpoint pathways. Notably, in cells lacking the histone methylases Suv39h, in which pericentric domains do not show HP1 accumulation, p150 is dispensable for S-phase progression.


Assuntos
Proteínas Cromossômicas não Histona/química , Proteínas Cromossômicas não Histona/metabolismo , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Heterocromatina/metabolismo , Fase S/fisiologia , Animais , Sequência de Bases , Células Cultivadas , Fator 1 de Modelagem da Cromatina , Homólogo 5 da Proteína Cromobox , Proteínas Cromossômicas não Histona/genética , Dano ao DNA , Replicação do DNA , Proteínas de Ligação a DNA/genética , Camundongos , Células NIH 3T3 , Domínios e Motivos de Interação entre Proteínas , RNA Interferente Pequeno/genética
11.
Org Lett ; 25(6): 1030-1034, 2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36749351

RESUMO

A reductive detrifluoromethylation protocol has been developed making use of an earth-abundant alkoxide base and silicon hydride species. A variety of pyridine and quinoline substrates bearing alkyl, aryl, and amino functional groups are reduced in moderate to high yields. The reaction is chemoselective for C(sp2)-CF3 groups located at the 2-position on the pyridine ring, leaving trifluoromethyl groups located elsewhere on the molecule intact. Preliminary mechanistic studies demonstrate that the combination of silane and base generates a strongly reducing system that may transfer an electron to electron-deficient π systems.

12.
ACS Appl Mater Interfaces ; 15(50): 58897-58904, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38084015

RESUMO

Liquid crystal elastomers (LCEs) are a class of active materials that can generate rapid, reversible mechanical actuation in response to external stimuli. Fabrication methods for LCEs have remained a topic of intense research interest in recent years. One promising approach, termed 4D printing, combines the advantages of 3D printing with responsive materials, such as LCEs, to generate smart structures that not only possess user-defined static shapes but also can change their shape over time. To date, 4D-printed LCE structures have been limited to flat objects, restricting shape complexity and associated actuation for smart structure applications. In this work, we report the development of embedded 4D printing to extrude hydrophobic LCE ink into an aqueous, thixotropic gel matrix to produce free-standing, free-form 3D architectures without sacrificing the mechanical actuation properties. The ability to 4D print complex, free-standing 3D LCE architectures opens new avenues for the design and development of functional and responsive systems, such as reconfigurable metamaterials, soft robotics, or biomedical devices.

13.
ACS Med Chem Lett ; 14(12): 1673-1681, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38116446

RESUMO

SHP2 has emerged as an important target for oncology small-molecule drug discovery. As a nonreceptor tyrosine phosphatase within the MAPK pathway, it has been shown to control cell growth, differentiation, and oncogenic transformation. We used structure-based design to find a novel class of potent and orally bioavailable SHP2 inhibitors. Our efforts led to the discovery of the 5-azaquinoxaline as a new core for developing this class of compounds. Optimization of the potency and properties of this scaffold generated compound 30, that exhibited potent in vitro SHP2 inhibition and showed excellent in vivo efficacy and pharmacokinetic profile.

14.
Cancer Discov ; 13(8): 1789-1801, 2023 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-37269335

RESUMO

Rationally targeted therapies have transformed cancer treatment, but many patients develop resistance through bypass signaling pathway activation. PF-07284892 (ARRY-558) is an allosteric SHP2 inhibitor designed to overcome bypass-signaling-mediated resistance when combined with inhibitors of various oncogenic drivers. Activity in this setting was confirmed in diverse tumor models. Patients with ALK fusion-positive lung cancer, BRAFV600E-mutant colorectal cancer, KRASG12D-mutant ovarian cancer, and ROS1 fusion-positive pancreatic cancer who previously developed targeted therapy resistance were treated with PF-07284892 on the first dose level of a first-in-human clinical trial. After progression on PF-07284892 monotherapy, a novel study design allowed the addition of oncogene-directed targeted therapy that had previously failed. Combination therapy led to rapid tumor and circulating tumor DNA (ctDNA) responses and extended the duration of overall clinical benefit. SIGNIFICANCE: PF-07284892-targeted therapy combinations overcame bypass-signaling-mediated resistance in a clinical setting in which neither component was active on its own. This provides proof of concept of the utility of SHP2 inhibitors in overcoming resistance to diverse targeted therapies and provides a paradigm for accelerated testing of novel drug combinations early in clinical development. See related commentary by Hernando-Calvo and Garralda, p. 1762. This article is highlighted in the In This Issue feature, p. 1749.


Assuntos
Neoplasias Pulmonares , Proteínas Tirosina Quinases , Humanos , Proteínas Tirosina Quinases/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Oncogenes , Assistência Centrada no Paciente
15.
Nucleic Acids Res ; 38(22): 8120-30, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20705648

RESUMO

Activation-induced cytidine deaminase (AID) protein initiates Ig gene mutation by deaminating cytosines, converting them into uracils. Excision of AID-induced uracils by uracil-N-glycosylase is responsible for most transversion mutations at G:C base pairs. On the other hand, processing of AID-induced G:U mismatches by mismatch repair factors is responsible for most mutation at Ig A:T base pairs. Why mismatch processing should be error prone is unknown. One theory proposes that long patch excision in G1-phase leads to dUTP-incorporation opposite adenines as a result of the higher G1-phase ratio of nuclear dUTP to dTTP. Subsequent base excision at the A:U base pairs produced could then create non-instructional templates leading to permanent mutations at A:T base pairs (1). This compelling theory has remained untested. We have developed a method to rapidly modify DNA repair pathways in mutating mouse B cells in vivo by transducing Ig knock-in splenic mouse B cells with GFP-tagged retroviruses, then adoptively transferring GFP(+) cells, along with appropriate antigen, into primed congenic hosts. We have used this method to show that dUTP-incorporation is unlikely to be the cause of AID-induced mutation of A:T base pairs, and instead propose that A:T mutations might arise as an indirect consequence of nucleotide paucity during AID-induced DNA repair.


Assuntos
Adenina/química , Nucleotídeos de Desoxiuracil/metabolismo , Genes de Imunoglobulinas , Mutação , Timina/química , Animais , Pareamento de Bases , Expressão Gênica , Centro Germinativo/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Pirofosfatases/metabolismo , Retroviridae/genética , Retroviridae/metabolismo
16.
BMJ Open ; 12(3): e056974, 2022 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-35332044

RESUMO

OBJECTIVE: To improve our understanding of cancer in adults with intellectual disabilities. DESIGN: Population-based study using linked data about deceased adults from the Learning (Intellectual) Disabilities Mortality Review (LeDeR) programme, the national cancer registry and NHS Digital. SETTING: England. PARTICIPANTS: 1096 adults with intellectual disabilities identified by the LeDeR programme who died between 1 January 2017 and 31 December 2019. OUTCOME MEASURE: Any form of cancer listed as a long-term health condition by a LeDeR reviewer or 10th edition of the International Classification of Diseases codes C00-D49 included on Parts I or II of the Medical Certificate of Cause of Death. RESULTS: In decedents with intellectual disabilities and cancer, more than a third (35%; n=162) had cancer diagnosed via emergency presentations. Almost half (45%; n=228) of cancers were at stage IV when diagnosed. More than a third (36%; n=309) of underlying causes of deaths were of cancers of the digestive system; almost half of these (48%; n=147) were cancer of the colon, rectum or anus. Of those who died with colorectal cancer, 43% were below the age threshold for colorectal screening. CONCLUSIONS: In decedents with intellectual disabilities, symptoms suggestive of cancer had tended to be identified most frequently as an emergency and at a late stage. There is a need for greater awareness of symptoms of cancer in this population, a lower threshold for referral by General Practitioners (GPs), accelerated access to diagnosis and treatment and consideration paid to lowering the age for colorectal screening.


Assuntos
Neoplasias Colorretais , Deficiência Intelectual , Adulto , Causas de Morte , Humanos , Deficiência Intelectual/complicações , Deficiência Intelectual/epidemiologia , Sistema de Registros , Web Semântica
17.
Adv Sci (Weinh) ; 9(14): e2200770, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35274480

RESUMO

The development of chemistry is reported to implement selective dual-wavelength olefin metathesis polymerization for continuous additive manufacturing (AM). A resin formulation based on dicyclopentadiene is produced using a latent olefin metathesis catalyst, various photosensitizers (PSs) and photobase generators (PBGs) to achieve efficient initiation at one wavelength (e.g., blue light) and fast catalyst decomposition and polymerization deactivation at a second (e.g., UV-light). This process enables 2D stereolithographic (SLA) printing, either using photomasks or patterned, collimated light. Importantly, the same process is readily adapted for 3D continuous AM, with printing rates of 36 mm h-1 for patterned light and up to 180 mm h-1 using un-patterned, high intensity light.


Assuntos
Alcenos , Impressão Tridimensional , Alcenos/química , Catálise , Luz , Polimerização
18.
J Vasc Surg Venous Lymphat Disord ; 10(2): 382-389.e2, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34358671

RESUMO

OBJECTIVE: The present study sought to determine whether protein-truncating variants (PTVs) in PIEZO1 and CASZ1 genes, previously shown to be associated with varicose veins, were associated with an altered risk of varicose veins. METHODS: An exome sequence database of 131,918 participants from the Geisinger MyCode Community Health Initiative was used to identify individuals with genetic variants in the PIEZO1 or CASZ1 gene. Clinical phenotypes, including varicose vein diagnoses, were determined by analysis of the electronic health record data. RESULTS: We identified 12,531 individuals (9.5%) with a diagnosis of varicose veins. Exome sequence data identified 92 PIEZO1 PTVs in 305 heterozygous carriers. PIEZO1 PTVs were significantly enriched in those with varicose vein (0.37% of cases vs 0.22% of controls; odds ratio [OR], 1.7; P = .0010). Nearly all varicose vein cases were associated with frameshift or stop-gain PTVs (OR, 3.0 for stop-gain [P = .0001]; OR, 2.9 for frameshift variants [P < .0001]). In the varicose vein cases, the PTV carriers were more likely to have an encounter with a vascular surgeon (62.5% for PTV carriers; 36.9% for noncarriers; P = .0003) and more likely to have received vein ablation therapy (OR, 6.9; P < .0001). No association was found between PIEZO1 PTVs and lymphedema, and no association was found for rare missense variants in PIEZO1 with varicose veins. PTVs in CASZ1 were extremely rare (16 total carriers), with none identified in those with varicose vein. CONCLUSIONS: Rare PTVs in PIEZO1 but not CASZ1 were associated with varicose veins and the need for vein ablation therapy. These results have demonstrated that PTVs in the PIEZO1 gene are rare but represent strong genetic risk factors for varicose veins and the need for vein ablation therapy. These results have also identified a potential biologic mechanism and target for the development of novel therapies.


Assuntos
Análise Mutacional de DNA , Sequenciamento do Exoma , Mutação da Fase de Leitura , Canais Iônicos/genética , Varizes/cirurgia , Adulto , Idoso , Registros Eletrônicos de Saúde , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Varizes/diagnóstico por imagem , Varizes/terapia
19.
Front Nutr ; 9: 932514, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35898708

RESUMO

Guidelines recommend primary care providers refer children with obesity to behavioral interventions, but given limited program availability, access, and parental engagement, referrals remain rare. We developed telehealth coaching interventions for families whose children received care at a health system in Pennsylvania, United States in 2019-2020. Intervention referrals were facilitated by the pediatrician and/or project team for 6-12-year-old children with obesity following well-child visits. Participants chose one of three 26-week interventions focused on healthy eating, physical activity, or a hybrid clinical/nutrition intervention. Interventions engaged parents as change agents, enhancing self-efficacy to model and reinforce behavior and providing resources to help create a healthy home environment. We enrolled 77 of 183 eligible parent/child dyads. We used mixed methods to evaluate the interventions. Repeated measures models among participants showed significant reductions in obesogenic nutrition behaviors post-intervention and at 1-year follow-up, including a reduction in sugar-sweetened beverage intake of 2.14 servings/week (95% confidence interval: -3.45, -0.82). There were also improvements in obesoprotective nutrition behaviors (e.g., frequency of family meals, parental self-efficacy related to meal management). One year post-baseline, we observed no significant differences in changes in body mass index (BMI) z-scores comparing child participants with matched controls. Given potential impacts of COVID-19 community restrictions on study outcomes, we conducted qualitative interviews with 13 participants during restrictions, which exemplified how disrupted routines constrained children's healthy behaviors but that intervention participation prepared parents by providing cooking and physical activities at home. Findings support the potential of a telehealth-delivered nutrition intervention to support adoption of healthy weight behaviors.

20.
ACS Appl Mater Interfaces ; 14(40): 45342-45351, 2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36191154

RESUMO

Additive manufacturing can enable the fabrication of batteries in nonconventional form factors, enabling higher practical energy density due to improved material packing efficiency of power sources in devices. Furthermore, energy density can be improved by transitioning from conventional Li-ion battery materials to lithium metal anodes and conversion cathodes. Iron disulfide (FeS2) is a prominent conversion cathode of commercial interest; however, the direct-ink-write (DIW) printing of FeS2 inks for custom-form battery applications has yet to be demonstrated or optimized. In this work, DIW printing of FeS2 inks is used to systematically investigate the impact of ink solid concentration on rheology, film shape retention on arbitrary surfaces, cathode morphology, and electrochemical cell performance. We find that cathodes with a ridged interface, produced from the filamentary extrusion of highly concentrated FeS2 inks (60-70% solids w/w%), exhibit optimal power, uniformity, and stability when cycled at higher rates (in excess of C/10). Meanwhile, cells with custom-form, wave-shaped electrodes (printed FeS2 cathodes and pressed lithium anodes) are demonstrated and shown to exhibit similar performance to comparable cells in planar configurations, demonstrating the feasibility of printing onto complex geometries. Overall, the DIW printing of FeS2 inks is shown to be a viable path toward the making of custom-form conversion lithium batteries. More broadly, ridging is found to optimize rate capability, a finding that may have a broad impact beyond FeS2 and syringe extrusion.

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