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1.
J Am Chem Soc ; 146(22): 15286-15292, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38776105

RESUMO

Architecture underlies the thermomechanical properties of polymers. Yet, few strategies are available to tune a polymer's architecture after it is prepared without altering its chemical composition. The ability to edit the architecture of a polymer would dramatically expand the accessible architecture-property space of polymeric materials. Herein, we disclose a backbone rearrangement approach to tune the short-chain branching of polymers. Specifically, we demonstrate that palladium(II)-catalyzed [3,3]-sigmatropic oxo-rearrangements can transform branched polyesters and polyurethanes to their linear counterparts. While the effects on materials properties are generally subtle in the case of polyesters, more dramatic changes are observed in the case of polyurethanes: two polyurethanes undergo a soluble-to-insoluble transition, and one exhibits a dramatic increase in both strain at break and toughness after rearrangement. Additionally, the incorporation of alkenes in the polymer backbone through the rearrangement enables facile deconstruction via ethenolysis. In all, we disclose a powerful and broad-scope strategy to edit the architecture of polymer backbones and thereby tune their physical and chemical properties.

2.
PLoS Biol ; 19(3): e3001081, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33705380

RESUMO

The apical complex is the instrument of invasion used by apicomplexan parasites, and the conoid is a conspicuous feature of this apparatus found throughout this phylum. The conoid, however, is believed to be heavily reduced or missing from Plasmodium species and other members of the class Aconoidasida. Relatively few conoid proteins have previously been identified, making it difficult to address how conserved this feature is throughout the phylum, and whether it is genuinely missing from some major groups. Moreover, parasites such as Plasmodium species cycle through 3 invasive forms, and there is the possibility of differential presence of the conoid between these stages. We have applied spatial proteomics and high-resolution microscopy to develop a more complete molecular inventory and understanding of the organisation of conoid-associated proteins in the model apicomplexan Toxoplasma gondii. These data revealed molecular conservation of all conoid substructures throughout Apicomplexa, including Plasmodium, and even in allied Myzozoa such as Chromera and dinoflagellates. We reporter-tagged and observed the expression and location of several conoid complex proteins in the malaria model P. berghei and revealed equivalent structures in all of its zoite forms, as well as evidence of molecular differentiation between blood-stage merozoites and the ookinetes and sporozoites of the mosquito vector. Collectively, we show that the conoid is a conserved apicomplexan element at the heart of the invasion mechanisms of these highly successful and often devastating parasites.


Assuntos
Apicomplexa/metabolismo , Plasmodium/metabolismo , Evolução Biológica , Citoesqueleto/metabolismo , Evolução Molecular , Malária/parasitologia , Mosquitos Vetores/metabolismo , Plasmodium/patogenicidade , Proteínas de Protozoários/metabolismo , Toxoplasma/metabolismo , Toxoplasma/patogenicidade
3.
Arterioscler Thromb Vasc Biol ; 43(7): e231-e237, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37128914

RESUMO

BACKGROUND: The goal of this study was to identify and characterize cell-cell interactions that facilitate endothelial tip cell fusion downstream of BMP (bone morphogenic protein)-mediated venous plexus formation. METHODS: High resolution and time-lapse imaging of transgenic reporter lines and loss-of-function studies were carried out to study the involvement of mesenchymal stromal cells during venous angiogenesis. RESULTS: BMP-responsive stromal cells facilitate timely and precise fusion of venous tip cells during developmental angiogenesis. CONCLUSIONS: Stromal cells are required for anastomosis of venous tip cells in the embryonic caudal hematopoietic tissue.


Assuntos
Proteínas Morfogenéticas Ósseas , Células-Tronco Mesenquimais , Animais , Fusão Celular , Proteínas Morfogenéticas Ósseas/genética , Proteínas Morfogenéticas Ósseas/metabolismo , Células-Tronco Mesenquimais/metabolismo , Animais Geneticamente Modificados , Comunicação Celular , Células Estromais/metabolismo
4.
Nutr Neurosci ; : 1-19, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38287652

RESUMO

Many epidemiological studies have shown the beneficial effects of a largely plant-based diet, and the strong association between the consumption of a Mediterranean-type diet with healthy aging including a lower risk of cognitive decline. The Mediterranean diet is characterized by a high intake of olive oil, fruits and vegetables and is rich in dietary fiber and polyphenols - both of which have been postulated to act as important mediators of these benefits. Polyphenols are large molecules produced by plants to protect them from environmental threats and injury. When ingested by humans, as little as 5% of these molecules are absorbed in the small intestine with the majority metabolized by the gut microbiota into absorbable simple phenolic compounds. Flavan-3-ols, a type of flavonoid, contained in grapes, berries, pome fruits, tea, and cocoa have been associated with many beneficial effects on several risk factors for cardiovascular disease, cognitive function and brain regions involved in memory formation. Both preclinical and clinical studies suggest that these brain and heart benefits can be attributed to endothelial vascular effects and anti-inflammatory properties among others. More recently the gut microbiota has emerged as a potential modulator of the aging brain and intriguingly polyphenols have been shown to alter microbiota composition and be metabolized by different microbial species. However, there is a need for well controlled studies in large populations to identify predictors of response, particularly given the vast inter-individual variation of human gut microbiota.

5.
Mol Biol Evol ; 39(10)2022 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-36108082

RESUMO

Mitochondrial genomes of apicomplexans, dinoflagellates, and chrompodellids that collectively make up the Myzozoa, encode only three proteins (Cytochrome b [COB], Cytochrome c oxidase subunit 1 [COX1], Cytochrome c oxidase subunit 3 [COX3]), contain fragmented ribosomal RNAs, and display extensive recombination, RNA trans-splicing, and RNA-editing. The early-diverging Perkinsozoa is the final major myzozoan lineage whose mitochondrial genomes remained poorly characterized. Previous reports of Perkinsus genes indicated independent acquisition of non-canonical features, namely the occurrence of multiple frameshifts. To determine both ancestral myzozoan and novel perkinsozoan mitochondrial genome features, we sequenced and assembled mitochondrial genomes of four Perkinsus species. These data show a simple ancestral genome with the common reduced coding capacity but disposition for rearrangement. We identified 75 frameshifts across the four species that occur as distinct types and that are highly conserved in gene location. A decoding mechanism apparently employs unused codons at the frameshift sites that advance translation either +1 or +2 frames to the next used codon. The locations of frameshifts are seemingly positioned to regulate protein folding of the nascent protein as it emerges from the ribosome. The cox3 gene is distinct in containing only one frameshift and showing strong selection against residues that are otherwise frequently encoded at the frameshift positions in cox1 and cob. All genes lack cysteine codons implying a reduction to 19 amino acids in these genomes. Furthermore, mitochondrion-encoded rRNA fragment complements are incomplete in Perkinsus spp. but some are found in the nuclear DNA suggesting import into the organelle. Perkinsus demonstrates further remarkable trajectories of organelle genome evolution including pervasive integration of frameshift translation into genome expression.


Assuntos
Genoma Mitocondrial , Códon , Cisteína/genética , Citocromos b/genética , DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética
6.
Surg Endosc ; 37(10): 7642-7648, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37491660

RESUMO

INTRODUCTION: Obesity is an increasingly prevalent public health problem often associated with poorly controlled gastroesophageal reflux disease. Fundoplication has been shown to have limited long-term efficacy in patients with morbid obesity and does not address additional weight-related co-morbidities. Roux-en-Y gastric bypass (RYGB) is the gold standard operation for durable resolution of GERD in patients with obesity, and is also used as a salvage operation for GERD after prior foregut surgery. Surgeons report access to RYGB as surgical treatment for GERD is often limited by RYGB-specific benefit exclusions embedded within insurance policies, but the magnitude and scope of this problem is unknown. METHODS: A 9-item survey evaluating surgeon practice and experience with insurance coverage for RYGB for GERD was developed and piloted by a SAGES Foregut Taskforce working group. This survey was then administered to surgeon members of the SAGES Foregut Taskforce and to surgeons participating in the SAGES Bariatrics and/or Foregut Facebook groups. RESULTS: 187 surgeons completed the survey. 89% reported using the RYGB as an anti-reflux procedure. 44% and 26% used a BMI of 35 kg/m2 and 30 kg/m2 respectively as cutoff for the RYGB. 89% viewed RYGB as the procedure of choice for GERD after bariatric surgery. 69% reported using RYGB to address recurrent reflux secondary to failed fundoplication. 74% of responders experienced trouble with insurance coverage at least half the time RYGB was offered for GERD, and 8% reported they were never able to get approval for RYGB for GERD indications in their patient populations. CONCLUSION: For many patients, GERD and obesity are related diseases that are best addressed with RYGB. However, insurance coverage for RYGB for GERD is often limited by policies which run contrary to evidence-based medicine. Advocacy is critical to improve access to appropriate surgical care for GERD in patients with obesity.


Assuntos
Derivação Gástrica , Refluxo Gastroesofágico , Seguro , Obesidade Mórbida , Cirurgiões , Humanos , Derivação Gástrica/métodos , Refluxo Gastroesofágico/cirurgia , Refluxo Gastroesofágico/complicações , Obesidade Mórbida/cirurgia , Obesidade Mórbida/complicações , Estudos Retrospectivos , Resultado do Tratamento
7.
Hum Mol Genet ; 29(16): 2723-2735, 2020 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-32720677

RESUMO

The Forkhead Box C1 (FOXC1) gene encodes a forkhead/winged helix transcription factor involved in embryonic development. Mutations in this gene cause dysgenesis of the anterior segment of the eye, most commonly Axenfeld-Rieger syndrome (ARS), often with other systemic features. The developmental mechanisms and pathways regulated by FOXC1 remain largely unknown. There are two conserved orthologs of FOXC1 in zebrafish, foxc1a and foxc1b. To further examine the role of FOXC1 in vertebrates, we generated foxc1a and foxc1b single knockout zebrafish lines and bred them to obtain various allelic combinations. Three genotypes demonstrated visible phenotypes: foxc1a-/- single homozygous and foxc1-/- double knockout homozygous embryos presented with similar characteristics comprised of severe global vascular defects and early lethality, as well as microphthalmia, periocular edema and absence of the anterior chamber of the eye; additionally, fish with heterozygous loss of foxc1a combined with homozygosity for foxc1b (foxc1a+/-;foxc1b-/-) demonstrated craniofacial defects, heart anomalies and scoliosis. All other single and combined genotypes appeared normal. Analysis of foxc1 expression detected a significant increase in foxc1a levels in homozygous and heterozygous mutant eyes, suggesting a mechanism for foxc1a upregulation when its function is compromised; interestingly, the expression of another ARS-associated gene, pitx2, was responsive to the estimated level of wild-type Foxc1a, indicating a possible role for this protein in the regulation of pitx2 expression. Altogether, our results support a conserved role for foxc1 in the formation of many organs, consistent with the features observed in human patients, and highlight the importance of correct FOXC1/foxc1 dosage for vertebrate development.


Assuntos
Segmento Anterior do Olho/anormalidades , Anormalidades do Olho/genética , Oftalmopatias Hereditárias/genética , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição/genética , Proteínas de Peixe-Zebra/genética , Alelos , Animais , Segmento Anterior do Olho/patologia , Desenvolvimento Embrionário/genética , Anormalidades do Olho/patologia , Oftalmopatias Hereditárias/patologia , Dosagem de Genes/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Genótipo , Cardiopatias Congênitas/genética , Cardiopatias Congênitas/patologia , Heterozigoto , Homozigoto , Humanos , Mutação/genética , Escoliose/genética , Escoliose/patologia , Peixe-Zebra/genética
8.
J Cell Sci ; 134(5)2020 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-32501284

RESUMO

Eukaryotic cell proliferation requires chromosome replication and precise segregation to ensure daughter cells have identical genomic copies. Species of the genus Plasmodium, the causative agents of malaria, display remarkable aspects of nuclear division throughout their life cycle to meet some peculiar and unique challenges to DNA replication and chromosome segregation. The parasite undergoes atypical endomitosis and endoreduplication with an intact nuclear membrane and intranuclear mitotic spindle. To understand these diverse modes of Plasmodium cell division, we have studied the behaviour and composition of the outer kinetochore NDC80 complex, a key part of the mitotic apparatus that attaches the centromere of chromosomes to microtubules of the mitotic spindle. Using NDC80-GFP live-cell imaging in Plasmodium berghei, we observe dynamic spatiotemporal changes during proliferation, including highly unusual kinetochore arrangements during sexual stages. We identify a very divergent candidate for the SPC24 subunit of the NDC80 complex, previously thought to be missing in Plasmodium, which completes a canonical, albeit unusual, NDC80 complex structure. Altogether, our studies reveal the kinetochore to be an ideal tool to investigate the non-canonical modes of chromosome segregation and cell division in Plasmodium.


Assuntos
Parasitos , Plasmodium , Animais , Divisão Celular , Segregação de Cromossomos/genética , Cinetocoros , Microtúbulos , Mitose/genética , Plasmodium/genética , Fuso Acromático/genética
9.
Exp Eye Res ; 225: 109219, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35985530

RESUMO

Children that undergo intraocular surgery have an exaggerated postoperative response compared to adults that can result in significant postoperative challenges and reduced post-operative visual acuity. Rabbits were used as an animal model for investigating aging differences, treatment options, and surgical techniques for anterior chamber surgical interventions due to similarities in anterior chamber size and decreasing postoperative response with age. In our study, juvenile and adult rabbits underwent lensectomy with intraocular lens (IOL) insertion to determine how ocular RNA transcripts and proteins change with age. Rabbits underwent lensectomy with IOL insertion, and aqueous humor (AH) was collected immediately prior to surgery and at the peak of the postoperative response on post-operative day 3. Proteins related to coagulation and inflammation were assessed using targeted mass spectrometry. In addition, the cornea and iris/ciliary body tissues were dissected, and transcripts analyzed using RNA sequencing. While clinically, juvenile rabbits have greater fibrin formation following intraocular surgery compared to older rabbits, this change does not appear to be related to relative abundance levels of coagulation and inflammatory proteins in the AH. Gene transcript levels from a variety of immune response and inflammatory pathways reflected significant increases when comparing operated to unoperated ocular tissues, indicating the significant impact that surgery has on each ocular structure. This work further advances our understanding of how the rabbit eye proteomic and transcriptomic changes in response to surgery with aging, as we seek to ultimately identify the mechanisms for the exaggerated postoperative responses after pediatric intraocular surgery.


Assuntos
Lentes Intraoculares , Transcriptoma , Animais , Coelhos , Proteômica , Corpo Ciliar , Envelhecimento
10.
Catheter Cardiovasc Interv ; 99(1): 19-26, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33871159

RESUMO

BACKGROUND: Among acute myocardial infarction patients with cardiogenic shock (AMICS), a number of key variables predict mortality, including cardiac arrest (CA) and shock classification as proposed by Society for Cardiovascular Angiography and Intervention (SCAI). Given this prognostic importance, we examined the frequency of reporting of high risk variables in published randomized controlled trials (RCTs) of AMICS patients. METHODS: We identified 15 RCTs enrolling 2,500 AMICS patients and then reviewed rates of CA, baseline neurologic status, right heart catheterization data, lactate levels, inotrope and vasopressor requirement, hypothermia, mechanical ventilation, left ventricular ejection fraction (LVEF), mechanical circulatory support, and specific cause of death based on the primary manuscript and Data in S1. RESULTS: A total of 2,500 AMICS patients have been enrolled in 15 clinical trials over 21 years with only four trials enrolling >80 patients. The reporting frequency and range for key prognostic factors was: neurologic status (0% reported), hypothermia (28% reported, prevalence 33-75%), specific cause of death (33% reported), cardiac index and wedge pressure (47% reported, range 1.6-2.3 L min-1  m-2 and 15-24 mmHg), lactate (60% reported, range 4-7.7 mmol/L), LVEF (73% reported, range 25-45%), CA (80% reported, prevalence 0-92%), MCS (80% reported, prevalence 13-100%), and mechanical ventilation (93% reported, prevalence 35-100%). This variability was reflected in the 30-day mortality which ranged from 20-73%. CONCLUSIONS: In a comprehensive review of seminal RCTs in AMICS, important predictors of outcome were frequently not reported. Future efforts to standardize CS trial data collection and reporting may allow for better assessment of novel therapies for AMICS.


Assuntos
Coração Auxiliar , Infarto do Miocárdio , Humanos , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/terapia , Choque Cardiogênico/diagnóstico , Choque Cardiogênico/etiologia , Choque Cardiogênico/terapia , Volume Sistólico , Resultado do Tratamento
11.
Exerc Sport Sci Rev ; 50(3): 137-144, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35522248

RESUMO

Aging induces physiological and molecular changes in the heart that increase the risk for heart disease. Several of these changes are targetable by exercise. We hypothesize that the mechanisms by which exercise improves cardiac function in the aged heart differ from those in the young exercised heart.


Assuntos
Miocárdio , Remodelação Ventricular , Idoso , Envelhecimento/fisiologia , Coração , Humanos , Remodelação Ventricular/fisiologia
12.
BMC Gastroenterol ; 22(1): 300, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35725375

RESUMO

BACKGROUND: Small intestinal bacterial overgrowth (SIBO) is a condition of unknown prevalence characterized by an excessive amount of bacteria in the small bowel, typically resulting in vague gastrointestinal symptoms with bloating being most commonly reported. Here we describe a severe case of SIBO leading to small bowel necrosis requiring surgical intervention. CASE PRESENTATION: A 55-year-old Hispanic female with gastric outlet obstruction secondary to a newly diagnosed gastric adenocarcinoma, receiving neoadjuvant chemotherapy, developed bloody gastrostomy output and rapidly progressing nausea and abdominal distention 3 days after jejunostomy tube placement and initiation of jejunal enteral nutrition. Imaging revealed diffuse pneumatosis and portal venous gas. Surgical exploration confirmed segmental bowel necrosis requiring resection. Histologic findings were consistent with SIBO. CONCLUSIONS: Presentation of severe SIBO in the setting of intestinal stasis secondary to gastric outlet after initiation of enteral feeds is a rare phenomenon. Early recognition and diagnosis of SIBO is critical in minimizing patient morbidity and mortality.


Assuntos
Síndrome da Alça Cega , Gastroenteropatias , Enteropatias , Síndrome da Alça Cega/etiologia , Feminino , Gastroenteropatias/patologia , Humanos , Jejunostomia , Jejuno/patologia , Pessoa de Meia-Idade , Necrose
13.
Clin Radiol ; 77(4): 291-298, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35177228

RESUMO

AIM: To prospectively analyse patients undergoing magnetic seed (Magseed) localisation (MSL) to evaluate the outcome, and to retrospectively compare re-excision rates for MSL with previous wire-guided localisation (WGL) to assess the hypothesis that the introduction of MSL may lead to a lower re-excision rate. MATERIALS AND METHODS: MSL commenced at University Hospital Crosshouse in December 2017. No other changes were made to radiological or surgical practice during this time. Data were collected prospectively on all patients undergoing MSL between December 2017 and December 2019, in a single breast unit. Data were gathered retrospectively on patients who had undergone localised breast procedures between January 2016 and December 2019 for comparison of re-excision rates. RESULTS: Two hundred and fifty-five patients underwent MSL surgery between December 2017 and December 2019. Of those, 98% (n=250) patients underwent successful MSL at the first attempt. The Magseed was identified intraoperatively in 100% patients and surgical excision was performed. The re-excision rate reduced from 18.9% in 2016/2017, to 11.6% in 2018/2019 (p=0.098). CONCLUSION: In conclusion, Magseed localisation has proved to be a safe and effective way of localising breast lesions, with the advantage of high accuracy. The reduction in re-excision rates at University Hospital Crosshouse with the introduction of Magseed® localisation is a potential benefit, which requires further study.


Assuntos
Procedimentos de Cirurgia Plástica , Radiologia , Hospitais Universitários , Humanos , Estudos Retrospectivos
14.
Chemistry ; 27(31): 8195-8202, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33793976

RESUMO

Without solvents present, the often far-from-equilibrium environment in a mechanochemically driven synthesis can generate high-energy, non-stoichiometric products not observed from the same ratio of reagents used in solution. Ball milling 2 equiv. K[A'] (A'=[1,3-(SiMe3 )2 C3 H3 ]- ) with CaI2 yields a non-stoichiometric calciate, K[CaA'3 ], which initially forms a structure (1) likely containing a mixture of pi- and sigma-bound allyl ligands. Dissolved in arenes, the compound rearranges over the course of several days to a structure (2) with only η3 -bound allyl ligands, and that can be crystallized as a coordination polymer. If dissolved in alkanes, however, the rearrangement of 1 to 2 occurs within minutes. The structures of 1 and 2 have been modeled with DFT calculations, and 2 initiates the anionic polymerization of methyl methacrylate and isoprene; for the latter, under the mildest conditions yet reported for a heavy Group 2 species (one-atm pressure and room temperature).

15.
PLoS Biol ; 16(9): e2005642, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30208022

RESUMO

The phylum Apicomplexa comprises a group of obligate intracellular parasites that alternate between intracellular replicating stages and actively motile extracellular forms that move through tissue. Parasite cytosolic Ca2+ signalling activates motility, but how this is switched off after invasion is complete to allow for replication to begin is not understood. Here, we show that the cyclic adenosine monophosphate (cAMP)-dependent protein kinase A catalytic subunit 1 (PKAc1) of Toxoplasma is responsible for suppression of Ca2+ signalling upon host cell invasion. We demonstrate that PKAc1 is sequestered to the parasite periphery by dual acylation of PKA regulatory subunit 1 (PKAr1). Upon genetic depletion of PKAc1 we show that newly invaded parasites exit host cells shortly thereafter, in a perforin-like protein 1 (PLP-1)-dependent fashion. Furthermore, we demonstrate that loss of PKAc1 prevents rapid down-regulation of cytosolic [Ca2+] levels shortly after invasion. We also provide evidence that loss of PKAc1 sensitises parasites to cyclic GMP (cGMP)-induced Ca2+ signalling, thus demonstrating a functional link between cAMP and these other signalling modalities. Together, this work provides a new paradigm in understanding how Toxoplasma and related apicomplexan parasites regulate infectivity.


Assuntos
Sinalização do Cálcio , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Toxoplasma/enzimologia , Acilação , Animais , Cálcio/metabolismo , AMP Cíclico/metabolismo , Citosol/metabolismo , Fibroblastos/parasitologia , Interações Hospedeiro-Parasita , Humanos , Estágios do Ciclo de Vida , Camundongos , Parasitos/enzimologia , Parasitos/crescimento & desenvolvimento , Subunidades Proteicas/metabolismo , Proteínas de Protozoários , Transdução de Sinais , Toxoplasma/crescimento & desenvolvimento
16.
PLoS Biol ; 16(7): e2006333, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29965960

RESUMO

Our current understanding of biology is heavily based on a small number of genetically tractable model organisms. Most eukaryotic phyla lack such experimental models, and this limits our ability to explore the molecular mechanisms that ultimately define their biology, ecology, and diversity. In particular, marine protists suffer from a paucity of model organisms despite playing critical roles in global nutrient cycles, food webs, and climate. To address this deficit, an initiative was launched in 2015 to foster the development of ecologically and taxonomically diverse marine protist genetic models. The development of new models faces many barriers, some technical and others institutional, and this often discourages the risky, long-term effort that may be required. To lower these barriers and tackle the complexity of this effort, a highly collaborative community-based approach was taken. Herein, we describe this approach, the advances achieved, and the lessons learned by participants in this novel community-based model for research.


Assuntos
Comportamento Cooperativo , Modelos Teóricos , Organismos Aquáticos/fisiologia , Eucariotos/classificação , Filogenia , Transformação Genética
17.
Gynecol Oncol ; 161(1): 56-62, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33536126

RESUMO

OBJECTIVE: To determine if laparoscopy is a cost-effective way to assess disease resectability in patients with newly diagnosed advanced ovarian cancer. METHODS: A cost-effectiveness analysis from a health care payer perspective was performed comparing two strategies: (1) a standard evaluation strategy, where a conventional approach to treatment planning was used to assign patients to either primary cytoreduction (PCS) or neoadjuvant chemotherapy with interval cytoreduction (NACT), and (2) a laparoscopy strategy, where patients considered candidates for PCS would undergo laparoscopy to triage between PCS or NACT based on the laparoscopy-predicted likelihood of complete gross resection. A microsimulation model was developed that included diagnostic work-up, surgical and adjuvant treatment, perioperative complications, and progression-free survival (PFS). Model parameters were derived from the literature and our published data. Effectiveness was defined in quality-adjusted PFS years. Results were tested with deterministic and probabilistic sensitivity analysis (PSA). The willingness-to-pay (WTP) threshold was set at $50,000 per year of quality-adjusted PFS. RESULTS: The laparoscopy strategy led to additional costs (average additional cost $7034) but was also more effective (average 4.1 months of additional quality-adjusted PFS). The incremental cost-effectiveness ratio (ICER) of laparoscopy was $20,376 per additional year of quality-adjusted PFS. The laparoscopy strategy remained cost-effective even as the cost added by laparoscopy increased. The benefit of laparoscopy was influenced by mitigation of serious complications and their associated costs. The laparoscopy strategy was cost-effective across a range of WTP thresholds. CONCLUSIONS: Performing laparoscopy is a cost-effective way to improve primary treatment planning for patients with untreated advanced ovarian cancer.


Assuntos
Laparoscopia/economia , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/cirurgia , Análise Custo-Benefício , Procedimentos Cirúrgicos de Citorredução/economia , Procedimentos Cirúrgicos de Citorredução/métodos , Feminino , Humanos , Laparoscopia/métodos , Modelos Econômicos , Modelos Estatísticos , Neoplasias Ovarianas/economia , Estados Unidos
18.
Am J Obstet Gynecol ; 225(1): 68.e1-68.e11, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33549538

RESUMO

BACKGROUND: More patients with ovarian cancer are being treated with poly(adenosine diphosphate-ribose) polymerase inhibitors because regulatory agencies have granted these drugs new approvals for a variety of treatment indications. However, poly(adenosine diphosphate-ribose) polymerase inhibitors are expensive. When administered as a maintenance therapy, these drugs may be administered for months or years. How much of this cost patients experience as out-of-pocket spending is unknown. OBJECTIVE: This study aimed to estimate the out-of-pocket spending that patients experience during poly(adenosine diphosphate-ribose) polymerase inhibitor treatment and to characterize which healthcare services account for that spending. STUDY DESIGN: A retrospective cohort study was performed with a sample of patients with ovarian cancer treated between 2014 and 2017 with olaparib, niraparib, or rucaparib. Patients were identified using MarketScan, a health insurance claims database. All insurance claims during poly(adenosine diphosphate-ribose) polymerase inhibitor treatment were collected. The primary outcome variable was the patients' out-of-pocket spending (copayment, coinsurance, and deductibles) during poly(adenosine diphosphate-ribose) polymerase inhibitor treatment for the medication itself. Other outcomes of interest included out-of-pocket spending for other healthcare services, the types and frequency of other healthcare services used, health plan spending, the estimated proportion of patients' household income used each month for healthcare, and patients' out-of-pocket spending immediately before poly(adenosine diphosphate-ribose) polymerase inhibitor treatment. RESULTS: We identified 503 patients with ovarian cancer with a median age of 55 years (interquartile range, 50-62 years); 83% of those had out-of-pocket spendings during poly(adenosine diphosphate-ribose) polymerase inhibitor treatment. The median treatment duration was 124 days (interquartile range, 66-240 days). The mean out-of-pocket spending for poly(adenosine diphosphate-ribose) polymerase inhibitors was $305 (standard deviation, $2275) per month. On average, this accounted for 44.8% (standard deviation, 34.8%) of the patients' overall monthly out-of-pocket spending. The mean out-of-pocket spending for other healthcare services was $165 (standard deviation, $769) per month. Health plans spent, on average, $12,661 (standard deviation, $15,668) per month for poly(adenosine diphosphate-ribose) polymerase inhibitors and $7108 (standard deviation, $15,254) per month for all other healthcare services. The cost sharing for office visits, laboratory tests, and imaging studies represented the majority of non-poly(adenosine diphosphate-ribose) polymerase inhibitor treatment out-of-pocket spending. The average amount patients paid for all healthcare services per month during poly(adenosine diphosphate-ribose) polymerase inhibitor treatment was $470 (standard deviation, $2407), which was estimated to be 8.7% of the patients' monthly household income. The mean out-of-pocket spending in the 12 months before poly(adenosine diphosphate-ribose) polymerase inhibitor treatment was $3110 (standard deviation, $6987). CONCLUSION: Patients can face high out-of-pocket costs for poly(adenosine diphosphate-ribose) polymerase inhibitors, although the sum of cost sharing for other healthcare services used during poly(adenosine diphosphate-ribose) polymerase inhibitor treatment is often higher. The spending on healthcare costs consumes a large proportion of these patients' household income. Patients with ovarian cancer experience high out-of-pocket costs for healthcare, both before and during poly(adenosine diphosphate-ribose) polymerase inhibitor treatment.


Assuntos
Custo Compartilhado de Seguro , Neoplasias Ovarianas/tratamento farmacológico , Inibidores de Poli(ADP-Ribose) Polimerases/economia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Estudos de Coortes , Feminino , Gastos em Saúde , Humanos , Revisão da Utilização de Seguros/economia , Reembolso de Seguro de Saúde/economia , Pessoa de Meia-Idade , Ftalazinas/economia , Ftalazinas/uso terapêutico , Piperazinas/economia , Piperazinas/uso terapêutico , Estudos Retrospectivos , Fatores de Tempo
19.
Circ Res ; 124(5): 769-778, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30602360

RESUMO

RATIONALE: Postconditioning at the time of primary percutaneous coronary intervention (PCI) for ST-segment-elevation myocardial infarction may reduce infarct size and improve myocardial salvage. However, clinical trials have shown inconsistent benefit. OBJECTIVE: We performed the first National Heart, Lung, and Blood Institute-sponsored trial of postconditioning in the United States using strict enrollment criteria to optimize the early benefits of postconditioning and assess its long-term effects on left ventricular (LV) function. METHODS AND RESULTS: We randomized 122 ST-segment-elevation myocardial infarction patients to postconditioning (4, 30 seconds PTCA [percutaneous transluminal coronary angioplasty] inflations/deflations)+PCI (n=65) versus routine PCI (n=57). All subjects had an occluded major epicardial artery (thrombolysis in myocardial infarction=0) with ischemic times between 1 and 6 hours with no evidence of preinfarction angina or collateral blood flow. Cardiac magnetic resonance imaging measured at 2 days post-PCI showed no difference between the postconditioning group and control in regards to infarct size (22.5±14.5 versus 24.0±18.5 g), myocardial salvage index (30.3±15.6% versus 31.5±23.6%), or mean LV ejection fraction. Magnetic resonance imaging at 12 months showed a significant recovery of LV ejection fraction in both groups (61.0±11.4% and 61.4±9.1%; P<0.01). Subjects randomized to postconditioning experienced more favorable remodeling over 1 year (LV end-diastolic volume =157±34 to 150±38 mL) compared with the control group (157±40 to 165±45 mL; P<0.03) and reduced microvascular obstruction ( P=0.05) on baseline magnetic resonance imaging and significantly less adverse LV remodeling compared with control subjects with microvascular obstruction ( P<0.05). No significant adverse events were associated with the postconditioning protocol and all patients but one (hemorrhagic stroke) survived through 1 year of follow-up. CONCLUSIONS: We found no early benefit of postconditioning on infarct size, myocardial salvage index, and LV function compared with routine PCI. However, postconditioning was associated with improved LV remodeling at 1 year of follow-up, especially in subjects with microvascular obstruction. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov . Unique identifier: NCT01324453.


Assuntos
Circulação Coronária , Pós-Condicionamento Isquêmico/métodos , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Idoso , Feminino , Humanos , Pós-Condicionamento Isquêmico/efeitos adversos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Minnesota , Miocárdio/patologia , National Heart, Lung, and Blood Institute (U.S.) , Intervenção Coronária Percutânea/efeitos adversos , Recuperação de Função Fisiológica , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem , Infarto do Miocárdio com Supradesnível do Segmento ST/fisiopatologia , Volume Sistólico , Fatores de Tempo , Sobrevivência de Tecidos , Resultado do Tratamento , Estados Unidos , Função Ventricular Esquerda , Remodelação Ventricular
20.
BMC Biol ; 18(1): 139, 2020 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-33050904

RESUMO

BACKGROUND: Some dinoflagellates cause harmful algal blooms, releasing toxic secondary metabolites, to the detriment of marine ecosystems and human health. Our understanding of dinoflagellate toxin biosynthesis has been hampered by their unusually large genomes. To overcome this challenge, for the first time, we sequenced the genome, microRNAs, and mRNA isoforms of a basal dinoflagellate, Amphidinium gibbosum, and employed an integrated omics approach to understand its secondary metabolite biosynthesis. RESULTS: We assembled the ~ 6.4-Gb A. gibbosum genome, and by probing decoded dinoflagellate genomes and transcriptomes, we identified the non-ribosomal peptide synthetase adenylation domain as essential for generation of specialized metabolites. Upon starving the cells of phosphate and nitrogen, we observed pronounced shifts in metabolite biosynthesis, suggestive of post-transcriptional regulation by microRNAs. Using Iso-Seq and RNA-seq data, we found that alternative splicing and polycistronic expression generate different transcripts for secondary metabolism. CONCLUSIONS: Our genomic findings suggest intricate integration of various metabolic enzymes that function iteratively to synthesize metabolites, providing mechanistic insights into how dinoflagellates synthesize secondary metabolites, depending upon nutrient availability. This study provides insights into toxin production associated with dinoflagellate blooms. The genome of this basal dinoflagellate provides important clues about dinoflagellate evolution and overcomes the large genome size, which has been a challenge previously.


Assuntos
Dinoflagellida/metabolismo , Genoma de Protozoário , MicroRNAs/análise , Isoformas de RNA/análise , RNA de Protozoário/análise , Metabolismo Secundário , Dinoflagellida/genética , RNA de Algas/análise
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