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1.
Mol Pharm ; 21(5): 2223-2237, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38552144

RESUMO

The fibrillation of therapeutic peptides can present significant quality concerns and poses challenges for manufacturing and storage. A fundamental understanding of the mechanisms of fibrillation is critical for the rational design of fibrillation-resistant peptide drugs and can accelerate product development by guiding the selection of solution-stable candidates and formulations. The studies reported here investigated the effects of structural modifications on the fibrillation of a 29-residue peptide (PepA) and two sequence modified variants (PepB, PepC). The C-terminus of PepA was amidated, whereas both PepB and PepC retained the carboxylate, and Ser16 in PepA and PepB was substituted with a helix-stabilizing residue, α-aminoisobutyric acid (Aib), in PepC. In thermal denaturation studies by far-UV CD spectroscopy and fibrillation kinetic studies by fluorescence and turbidity measurements, PepA and PepB showed heat-induced conformational changes and were found to form fibrils, whereas PepC did not fibrillate and showed only minor changes in the CD signal. Pulsed hydrogen-deuterium exchange mass spectrometry (HDX-MS) showed a high degree of protection from HD exchange in mature PepA fibrils and its proteolytic fragments, indicating that most of the sequence had been incorporated into the fibril structure and occurred nearly simultaneously throughout the sequence. The effects of the net peptide charge and formulation pH on fibrillation kinetics were investigated. In real-time stability studies of two formulations of PepA at pH's 7.4 and 8.0, analytical methods detected significant changes in the stability of the formulations at different time points during the study, which were not observed during accelerated studies. Additionally, PepA samples were withdrawn from real-time stability and subjected to additional stress (40 °C, continuous shaking) to induce fibrillation; an approach that successfully amplified oligomers or prefibrillar species previously undetected in a thioflavin T assay. Taken together, these studies present an approach to differentiate and characterize fibrillation risk in structurally related peptides under accelerated and real-time conditions, providing a model for rapid, iterative structural design to optimize the stability of therapeutic peptides.


Assuntos
Desenho de Fármacos , Peptídeos , Peptídeos/química , Dicroísmo Circular/métodos , Estabilidade de Medicamentos , Sequência de Aminoácidos , Cinética , Ácidos Aminoisobutíricos/química , Estabilidade Proteica , Espectrometria de Massas/métodos
2.
Am J Med Genet C Semin Med Genet ; 196(1): e32074, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37946659

RESUMO

Patients with Down syndrome have significant specialized health care needs. Our objective was to understand the needs, satisfaction, and online habits of caregivers as they care for persons with Down syndrome. A mixed-method survey was distributed through REDCap from April 2022 to June 2022 in the United States; a Spanish-translated version was distributed through SurveyMonkey from August 2022 to March 2023 in Mexico. We received 290 completed responses from the United States and 58 from caregivers in Mexico. We found that current health care options are not meeting the needs of many individuals with DS in both the United States (39.7%) and Mexico (46.6%). Caregivers expressed frustrations with the inaccessibility and inapplicability of health care information. In particular, they often found the volume of information overwhelming, given their limited medical background. Additionally, health care recommendations were not customized and lacked practical recommendations. Most caregivers in both the United States (72.1%) and Mexico (82.8%) believe it is not easy to find answers to medical questions about their loved ones with DS. Online platforms with customized, specific health information related to DS could offer innovative solutions to these unmet needs for families and primary care providers.


Assuntos
Cuidadores , Síndrome de Down , Humanos , Estados Unidos , Alfabetização , Atenção à Saúde , Satisfação Pessoal
3.
J Immunother Cancer ; 11(10)2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37857525

RESUMO

Acral melanoma (AM) has distinct characteristics as compared with cutaneous melanoma and exhibits poor response to immune checkpoint inhibitors (ICIs). Tumor-intrinsic mechanisms of immune exclusion have been identified in many cancers but less studied in AM. We characterized clinically annotated tumors from patients diagnosed with AM at our institution in correlation with ICI response using whole transcriptome RNAseq, whole exome sequencing, CD8 immunohistochemistry, and multispectral immunofluorescence imaging. A defined interferon-γ-associated T cell-inflamed gene signature was used to categorize tumors into non-T cell-inflamed and T cell-inflamed phenotypes. In combination with AM tumors from two published studies, we systematically assessed the immune landscape of AM and detected differential gene expression and pathway activation in a non-T cell-inflamed tumor microenvironment (TME). Two single-cell(sc) RNAseq AM cohorts and 11 bulk RNAseq cohorts of various tumor types were used for independent validation on pathways associated with lack of ICI response. In total, 892 specimens were included in this study. 72.5% of AM tumors showed low expression of the T cell-inflamed gene signature, with 23.9% of total tumors categorized as the non-T cell-inflamed phenotype. Patients of low CD3+CD8+PD1+ intratumoral T cell density showed poor prognosis. We identified 11 oncogenic pathways significantly upregulated in non-T cell-inflamed relative to T cell-inflamed TME shared across all three acral cohorts (MYC, HGF, MITF, VEGF, EGFR, SP1, ERBB2, TFEB, SREBF1, SOX2, and CCND1). scRNAseq analysis revealed that tumor cell-expressing pathway scores were significantly higher in low versus high T cell-infiltrated AM tumors. We further demonstrated that the 11 pathways were enriched in ICI non-responders compared with responders across cancers, including AM, cutaneous melanoma, triple-negative breast cancer, and non-small cell lung cancer. Pathway activation was associated with low expression of interferon stimulated genes, suggesting suppression of antigen presentation. Across the 11 pathways, fatty acid synthase and CXCL8 were unifying downstream target molecules suggesting potential nodes for therapeutic intervention. A unique set of pathways is associated with immune exclusion and ICI resistance in AM. These data may inform immunotherapy combinations for immediate clinical translation.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Melanoma , Neoplasias Cutâneas , Humanos , Neoplasias Cutâneas/genética , Microambiente Tumoral , Melanoma Maligno Cutâneo
4.
Res Sq ; 2023 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-37645831

RESUMO

Patients with tumors that do not respond to immune-checkpoint inhibition often harbor a non-T cell-inflamed tumor microenvironment, characterized by the absence of IFN-γ-associated CD8+ T cell and dendritic cell activation. Understanding the molecular mechanisms underlying immune exclusion in non-responding patients may enable the development of novel combination therapies. p38 MAPK is a known regulator of dendritic and myeloid cells however a tumor-intrinsic immunomodulatory role has not been previously described. Here we identify tumor cell p38 signaling as a therapeutic target to potentiate anti-tumor immunity and overcome resistance to immune-checkpoint inhibitors (ICI). Molecular analysis of tumor tissues from patients with human papillomavirus-negative head and neck squamous carcinoma reveals a p38-centered network enriched in non-T cell-inflamed tumors. Pan-cancer single-cell RNA analysis suggests that p38 activation may be an immune-exclusion mechanism across multiple tumor types. P38 knockdown in cancer cell lines increases T cell migration, and p38 inhibition plus ICI in preclinical models shows greater efficacy compared to monotherapies. In a clinical trial of patients refractory to PD1/L1 therapy, pexmetinib, a p38 inhibitor, plus nivolumab demonstrated deep and durable clinical responses. Targeting of p38 with anti-PD1 has the potential to induce the T cell-inflamed phenotype and overcome immunotherapy resistance.

6.
Ann Surg Oncol ; 30(12): 7517-7526, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37314541

RESUMO

BACKGROUND: Appendiceal mucinous neoplasms (AMNs) with disseminated disease (pseudomyxoma peritonei) are heterogeneous tumors with variable clinicopathologic behavior. Despite the development of prognostic systems, objective biomarkers are needed to stratify patients. With the advent of next-generation sequencing (NGS), it remains unclear if molecular testing can improve the evaluation of disseminated AMN patients. METHODS: Targeted NGS was performed for 183 patients and correlated with clinicopathologic features to include American Joint Committee on Cancer/World Health Organization (AJCC/WHO) histologic grade, peritoneal cancer index (PCI), completeness of cytoreduction (CC) score, and overall survival (OS). RESULTS: Genomic alterations were identified for 179 (98%) disseminated AMNs. Excluding mitogen-activated protein kinase genes and GNAS due to their ubiquitous nature, collective genomic alterations in TP53, SMAD4, CDKN2A, and the mTOR genes were associated with older mean age, higher AJCC/WHO histologic grade, lymphovascular invasion, perineural invasion, regional lymph node metastasis, and lower mean PCI (p < 0.040). Patients harboring TP53, SMAD4, ATM, CDKN2A, and/or mTOR gene alterations were found to have lower OS rates of 55% at 5 years and 14% at 10 years, compared with 88% at 5 years and 88% at 10 years for patients without the aforementioned alterations (p < 0.001). Based on univariate and multivariate analyses, genomic alterations in TP53, SMAD4, ATM, CDKN2A, and/or the mTOR genes in disseminated AMNs were a negative prognostic factor for OS and independent of AJCC/WHO histologic grade, PCI, CC score, and hyperthermic intraperitoneal chemotherapy treatment (p = 0.006). CONCLUSIONS: Targeted NGS improves the prognostic assessment of patients with disseminated AMNs and identifies patients who may require increased surveillance and/or aggressive management.


Assuntos
Adenocarcinoma Mucinoso , Neoplasias do Apêndice , Neoplasias Peritoneais , Pseudomixoma Peritoneal , Humanos , Pseudomixoma Peritoneal/genética , Pseudomixoma Peritoneal/terapia , Pseudomixoma Peritoneal/metabolismo , Adenocarcinoma Mucinoso/genética , Adenocarcinoma Mucinoso/terapia , Neoplasias do Apêndice/genética , Neoplasias do Apêndice/terapia , Neoplasias Peritoneais/genética , Neoplasias Peritoneais/terapia , Neoplasias Peritoneais/patologia , Sequenciamento de Nucleotídeos em Larga Escala , Serina-Treonina Quinases TOR/genética , Procedimentos Cirúrgicos de Citorredução
7.
Ann Surg ; 278(4): e789-e797, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37212422

RESUMO

OBJECTIVE: We report the development and validation of a combined DNA/RNA next-generation sequencing (NGS) platform to improve the evaluation of pancreatic cysts. BACKGROUND AND AIMS: Despite a multidisciplinary approach, pancreatic cyst classification, such as a cystic precursor neoplasm, and the detection of high-grade dysplasia and early adenocarcinoma (advanced neoplasia) can be challenging. NGS of preoperative pancreatic cyst fluid improves the clinical evaluation of pancreatic cysts, but the recent identification of novel genomic alterations necessitates the creation of a comprehensive panel and the development of a genomic classifier to integrate the complex molecular results. METHODS: An updated and unique 74-gene DNA/RNA-targeted NGS panel (PancreaSeq Genomic Classifier) was created to evaluate 5 classes of genomic alterations to include gene mutations (e.g., KRAS, GNAS, etc.), gene fusions and gene expression. Further, CEA mRNA ( CEACAM5 ) was integrated into the assay using RT-qPCR. Separate multi-institutional cohorts for training (n=108) and validation (n=77) were tested, and diagnostic performance was compared to clinical, imaging, cytopathologic, and guideline data. RESULTS: Upon creation of a genomic classifier system, PancreaSeq GC yielded a 95% sensitivity and 100% specificity for a cystic precursor neoplasm, and the sensitivity and specificity for advanced neoplasia were 82% and 100%, respectively. Associated symptoms, cyst size, duct dilatation, a mural nodule, increasing cyst size, and malignant cytopathology had lower sensitivities (41-59%) and lower specificities (56-96%) for advanced neoplasia. This test also increased the sensitivity of current pancreatic cyst guidelines (IAP/Fukuoka and AGA) by >10% and maintained their inherent specificity. CONCLUSIONS: PancreaSeq GC was not only accurate in predicting pancreatic cyst type and advanced neoplasia but also improved the sensitivity of current pancreatic cyst guidelines.


Assuntos
Cisto Pancreático , Neoplasias Pancreáticas , Humanos , RNA , Detecção Precoce de Câncer , Cisto Pancreático/diagnóstico , Cisto Pancreático/genética , Cisto Pancreático/patologia , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , DNA , Sequenciamento de Nucleotídeos em Larga Escala , Neoplasias Pancreáticas
8.
Cell Rep Med ; 4(4): 101013, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-37044094

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) has been left behind in the evolution of personalized medicine. Predictive markers of response to therapy are lacking in PDAC despite various histological and transcriptional classification schemes. We report an artificial intelligence (AI) approach to histologic feature examination that extracts a signature predictive of disease-specific survival (DSS) in patients with PDAC receiving adjuvant gemcitabine. We demonstrate that this AI-generated histologic signature is associated with outcomes following adjuvant gemcitabine, while three previously developed transcriptomic classification systems are not (n = 47). We externally validate this signature in an independent cohort of patients treated with adjuvant gemcitabine (n = 46). Finally, we demonstrate that the signature does not stratify survival outcomes in a third cohort of untreated patients (n = 161), suggesting that the signature is specifically predictive of treatment-related outcomes but is not generally prognostic. This imaging analysis pipeline has promise in the development of actionable markers in other clinical settings where few biomarkers currently exist.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Gencitabina , Inteligência Artificial , Desoxicitidina/uso terapêutico , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , Resultado do Tratamento , Biomarcadores , Neoplasias Pancreáticas
9.
Pharm Res ; 40(3): 701-710, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36797504

RESUMO

PURPOSE OR OBJECTIVE: Chemical and physical stabilities are two key features considered in pharmaceutical development. Chemical stability is typically reported as a combination of potency and degradation product. Moreover, fluorescent reporter Thioflavin-T is commonly used to measure physical stability. Executing stability studies is a lengthy process and requires extensive resources. To reduce the resources and shorten the process for stability studies during the development of a drug product, we introduce a machine learning-based model for predicting the chemical stability over time using both formulation conditions as well as aggregation curves. METHODS: In this work, we develop the relationships between the formulation, stability timepoint, and the chemical stability measurements and evaluated the performance on a random test set. We have developed a multilayer perceptron (MLP) for total degradation prediction and a random forest (RF) model for potency. RESULTS: The coefficient of determination (R2) of 0.945 and a mean absolute error (MAE) of 0.421 were achieved on the test set when using MLP for total degradation. Similarly, we achieved a R2 of 0.908 and MAE of 1.435 when predicting potency using the RF model. When physical stability measurements are included into the MLP model, the MAE of predicting TD decreases to 0.148. Using a similar strategy for potency prediction, the MAE decreases to 0.705 for the RF model. CONCLUSIONS: We conclude two important points: first, chemical stability can be modeled using machine learning techniques and second there is a relationship between the physical stability of a peptide and its chemical stability.


Assuntos
Aprendizado de Máquina , Redes Neurais de Computação , Algoritmo Florestas Aleatórias , Máquina de Vetores de Suporte
10.
Matrix Biol Plus ; 17: 100127, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36632559

RESUMO

Although most work has focused on resolution of collagen ECM, fibrosis resolution involves changes to several ECM proteins. The purpose of the current study was twofold: 1) to examine the role of MMP12 and elastin; and 2) to investigate the changes in degraded proteins in plasma (i.e., the "degradome") in a preclinical model of fibrosis resolution. Fibrosis was induced by 4 weeks carbon tetrachloride (CCl4) exposure, and recovery was monitored for an additional 4 weeks. Some mice were treated with daily MMP12 inhibitor (MMP408) during the resolution phase. Liver injury and fibrosis was monitored by clinical chemistry, histology and gene expression. The release of degraded ECM peptides in the plasma was analyzed using by 1D-LC-MS/MS, coupled with PEAKS Studio (v10) peptide identification. Hepatic fibrosis and liver injury rapidly resolved in this mouse model. However, some collagen fibrils were still present 28d after cessation of CCl4. Despite this persistent collagen presence, expression of canonical markers of fibrosis were also normalized. The inhibition of MMP12 dramatically delayed fibrosis resolution under these conditions. LC-MS/MS analysis identified that several proteins were being degraded even at late stages of fibrosis resolution. Calpains 1/2 were identified as potential new proteases involved in fibrosis resolution. CONCLUSION. The results of this study indicate that remodeling of the liver during recovery from fibrosis is a complex and highly coordinated process that extends well beyond the degradation of the collagenous scar. These results also indicate that analysis of the plasma degradome may yield new insight into the mechanisms of fibrosis recovery, and by extension, new "theragnostic" targets. Lastly, a novel potential role for calpain activation in the degradation and turnover of proteins was identified.

11.
Adv Physiol Educ ; 46(1): 179-189, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34914564

RESUMO

Professional skill development has emerged as an increasingly important facet of undergraduate training, specifically within science curricula. The primarily agreed on professional skills for a well-rounded scientist include teamwork, oral communication, written communication, and quantitative skills. The demand for these skills has been driven by employers and graduate/professional schools. To this end, instructors in higher education have begun to integrate professional skill development into their course design and student learning goals. However, the attitudes of students themselves toward the importance of different professional skills, the inclusion of these skills in their coursework, level of improvement, and end confidence has yet to be thoroughly characterized. It was the aim of this study to ascertain students' desire for the aforementioned professional skills within their undergraduate science programs by exploring student perceptions of professional skills inclusion, importance, improvement, and confidence and identify the local courses students recognize as utilizing "teamwork activities." Here we detail these attitudes in biomedical science undergraduates at Michigan State University. By using the Science Student Skills Inventory (SSSI), a previously validated assessment tool, we observed differences in student perceptions of professional skills when compared to previous SSSI studies. We also observed significant differences in attitudes between age groups in respect to writing and communication skills, differing perceptions of what constitutes teamwork, as well as gender differences in respect to attitudes around communication and ethical thinking skills. Our results give valuable insight into student perspectives on how professional skills are developed in their program. These data may be used to inform curriculum development within and across institutions.


Assuntos
Currículo , Estudantes , Comunicação , Humanos , Michigan , Pensamento
12.
J Pharm Sci ; 111(3): 655-662, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34666046

RESUMO

The presence of subvisible or visible particles in mAb formulations can pose significant challenges to pharmaceutical development as it can lead to reduced shelf life, batch rejection, and recalls. Among all type of particles, proteinaceous particles are the most concerning due to their potential role in immunogenicity. Nevertheless, the underlying mechanism for protein particle formation remains poorly understood. Past research highlighted the importance of interfaces and mechanical agitation in causing protein particle formation. Current research suggests that fatty acids, as impurities present in excipients or as a result of polysorbate degradation, can also induce protein assembly and promote particle formation. In this work, we assessed oleic and lauric acid for their impact on particle formation as each represents the main hydrolysis product of PS80 or PS20, respectively. It was found that co-existence of either fatty acids with 10 mg/mL mAb A can cause protein particles, with a similar morphology to those observed previously in mAb formulations. FTIR spectra showed that the particles are proteinaceous, heterogeneous in its composition, but contain corresponding fatty acids. Interestingly, it was found that oleic acid is significantly more effective in causing protein particles than lauric acid in these experiments. This suggests that PS20 containing formulations might have a lower likelihood to have protein particles compared to PS80 containing mAb formulations if hydrolysis of polysorbate were to occur. Lastly, the presence of 0.01% polysorbate in the mAb A formulation was able to fully mitigate the effect of fatty acids and reduce the protein particles significantly, suggesting a potential mechanism where interfacial action is involved. The present study can help to understand the root cause for protein particles in a mAb formulation where fatty acids are introduced because of polysorbate hydrolysis. With further work, it will help to shed light into product control strategy as well as design approaches for robust mAb products.


Assuntos
Ácidos Graxos , Polissorbatos , Anticorpos Monoclonais , Química Farmacêutica , Ácidos Láuricos , Tensoativos
13.
J Pharm Pract ; 35(5): 747-751, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33813934

RESUMO

BACKGROUND: Although strategies for optimization of pharmacologic therapy in patients with heart failure with reduced ejection fraction (HFrEF) are scripted by guidelines, data from HF registries suggests that guideline-directed medical therapies (GDMT) are underutilized among eligible patients. Whether this discrepancy reflects medication intolerance, contraindications, or a quality of care issue remains unclear. OBJECTIVE: The objective of this initiative was to identify reasons for underutilization and under-dosing of HFrEF therapy in patients at a large, academic medical center. METHODS: Among 500 patients with HFrEF enrolled in a quality improvement project at a tertiary center, we evaluated usage and dosing of 4 categories of GDMT: ACE inhibitors/Angiotensin Receptor Blockers (ACE-i/ARB), Angiotensin Receptor-Neprilysin Inhibitors (ARNi), beta blockers, and Mineralocorticoid Receptor Antagonists (MRA). Reasons for nonprescription and usage of suboptimal doses were abstracted from notes in the chart and from telephone review of previous medication trials with the patient. RESULTS: Of 500 patients identified, 472 subjects had complete data for analysis. Among eligible patients, ACE-i/ARB were prescribed in 81.4% (293 of 360) and beta blockers in 94.4% (442 of 468). Of these patients, 10.6% were prescribed target doses of ACE-i/ARB and 12.4% were prescribed target doses of beta blockers. Utilization of other categories of GDMT was lower, with 54% of eligible patients prescribed MRAs and 27% prescribed an ARNi. In most cases, the reasons for nonprescription or under-dosing of GDMT were not apparent on review of the health record or discussion with the patient. CONCLUSION: Clear rationale for nonprescription and under-dosing of GDMT often cannot be ascertained from detailed review and is only rarely related to documented medication intolerance or contraindications, suggesting an opportunity for quality improvement.


Assuntos
Insuficiência Cardíaca , Antagonistas Adrenérgicos beta/uso terapêutico , Antagonistas de Receptores de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina , Insuficiência Cardíaca/tratamento farmacológico , Humanos , Antagonistas de Receptores de Mineralocorticoides/uso terapêutico , Neprilisina/farmacologia , Neprilisina/uso terapêutico , Receptores de Angiotensina/uso terapêutico , Volume Sistólico
14.
Clin Gastroenterol Hepatol ; 20(4): 886-897, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-33278573

RESUMO

BACKGROUND & AIMS: The assessment of therapeutic response after neoadjuvant treatment and pancreatectomy for pancreatic ductal adenocarcinoma (PDAC) has been an ongoing challenge. Several limitations have been encountered when employing current grading systems for residual tumor. Considering endoscopic ultrasound (EUS) represents a sensitive imaging technique for PDAC, differences in tumor size between preoperative EUS and postoperative pathology after neoadjuvant therapy were hypothesized to represent an improved marker of treatment response. METHODS: For 340 treatment-naïve and 365 neoadjuvant-treated PDACs, EUS and pathologic findings were analyzed and correlated with patient overall survival (OS). A separate group of 200 neoadjuvant-treated PDACs served as a validation cohort for further analysis. RESULTS: Among treatment-naïve PDACs, there was a moderate concordance between EUS imaging and postoperative pathology for tumor size (r = 0.726, P < .001) and AJCC 8th edition T-stage (r = 0.586, P < .001). In the setting of neoadjuvant therapy, a decrease in T-stage correlated with improved 3-year OS rates (50% vs 31%, P < .001). Through recursive partitioning, a cutoff of ≥47% tumor size reduction was also found to be associated with improved OS (67% vs 32%, P < .001). Improved OS using a ≥47% threshold was validated using a separate cohort of neoadjuvant-treated PDACs (72% vs 36%, P < .001). By multivariate analysis, a reduction in tumor size by ≥47% was an independent prognostic factor for improved OS (P = .007). CONCLUSIONS: The difference in tumor size between preoperative EUS imaging and postoperative pathology among neoadjuvant-treated PDAC patients is an important prognostic indicator and may guide subsequent chemotherapeutic management.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Carcinoma Ductal Pancreático/diagnóstico por imagem , Carcinoma Ductal Pancreático/cirurgia , Endossonografia , Humanos , Terapia Neoadjuvante/métodos , Estadiamento de Neoplasias , Pancreatectomia , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/cirurgia , Prognóstico , Estudos Retrospectivos
15.
Artigo em Inglês | MEDLINE | ID: mdl-34741934

RESUMO

The potential of lipid nanoparticles (LNPs) as nucleic acid delivery vehicles has been demonstrated in recent years, culminating in the emergency use approval of LNP-based mRNA SARS-CoV-2 vaccines in late 2020. The determination of RNA content relative to LNP size can be important to the understanding of efficacy and adverse effects. This work presents the first description of a facile and rapid analytical method for online, size-dependent RNA payload distribution measurement using data from multi-angle light scattering, ultraviolet and refractive index detectors following separation of the LNPs by size-exclusion chromatography. The analysis was validated by size-based fractionation of the LNPs with subsequent offline analysis of the fractions. Four LNPs formulated with different PEG-lipids and different lipid compositions were tested. Good agreement was observed between the online and offline size-based RNA distributions among all four LNPs, demonstrating the utility of the online method for LNP-encapsulated RNA in general, and suggesting a means for simplified biophysical quantitation of a dosing-related critical quality attribute.


Assuntos
Vacinas contra COVID-19/química , Cromatografia em Gel/métodos , Portadores de Fármacos/química , Nanopartículas/química , RNA Mensageiro/química , RNA Viral/química , SARS-CoV-2/genética , COVID-19/virologia , Vacinas contra COVID-19/imunologia , Sistemas de Liberação de Medicamentos , Humanos , Lipídeos/química , Tamanho da Partícula , RNA Mensageiro/imunologia , RNA Viral/imunologia , SARS-CoV-2/química , SARS-CoV-2/imunologia
16.
J Surg Oncol ; 124(3): 308-316, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33893740

RESUMO

BACKGROUND AND OBJECTIVES: Neoadjuvant chemotherapy (NAT) for pancreatic adenocarcinoma (PDAC) is increasingly being utilized. However, a significant number of patients will experience early recurrence, possibly negating the benefit of surgery. We aimed to identify factors implicated in early disease recurrence. METHODS: A retrospective review of pancreaticoduodenectomies performed between 2005 and 2017 at our institution for PDAC following NAT was performed. A 6-month cut-off was used to stratify patients into early/late recurrence groups. Multivariate analysis was performed to identify predictors of recurrence. RESULTS: Of 273 patients, 64 (23%) developed early recurrence or died within 90 days of surgery. The median time to recurrence was 4 months (95% confidence interval [CI]: 2.2-4.3) in the early group versus 16 months (95% CI: 13.7-19.9) in the late group. The former had higher baseline and post-NAT Ca19-9 levels than the latter (472 vs. 153 IU/ml, p = 0.001 and 71 vs. 39 IU/ml, p = 0.005, respectively). A higher positive lymph node ratio significantly increased the risk of early recurrence (hazard ratio [HR]: 15.9, p < 0.001) while adjuvant chemotherapy was protective (HR: 0.4, p < 0.001). CONCLUSION: Our findings acknowledge the limitations of clinically measured factors used to ascertain response to NAT and underline the need for individualized molecular markers that take into consideration the specific tumor biology.


Assuntos
Recidiva Local de Neoplasia/patologia , Idoso , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/mortalidade , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Recidiva Local de Neoplasia/mortalidade , Estadiamento de Neoplasias , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Estudos Retrospectivos , Taxa de Sobrevida
17.
JAMA Cardiol ; 5(12): 1430-1434, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32936209

RESUMO

Importance: Optimal treatment of heart failure with reduced ejection fraction (HFrEF) is scripted by treatment guidelines, but many eligible patients do not receive guideline-directed medical therapy (GDMT) in clinical practice. Objective: To determine whether a remote, algorithm-driven, navigator-administered medication optimization program could enhance implementation of GDMT in HFrEF. Design, Setting, and Participants: In this case-control study, a population-based sample of patients with HFrEF was offered participation in a quality improvement program directed at GDMT optimization. Treating clinicians in a tertiary academic medical center who were caring for patients with heart failure and an ejection fraction of 40% or less (identified through an electronic health record-based search) were approached for permission to adjust medical therapy according to a sequential titration algorithm modeled on the current American College of Cardiology/American Heart Association heart failure guidelines. Navigators contacted participants by telephone to direct medication adjustment and conduct longitudinal surveillance of laboratory tests, blood pressure, and symptoms under supervision of a pharmacist, nurse practitioner, and heart failure cardiologist. Patients and clinicians declining to participate served as a control group. Exposures: Navigator-led remote optimization of GDMT compared with usual care. Main Outcomes and Measures: Proportion of patients receiving GDMT in the intervention and control groups at 3 months. Results: Of 1028 eligible patients (mean [SD] values: age, 68 [14] years; ejection fraction, 32% [8%]; and systolic blood pressure, 122 [18] mm Hg; 305 women (30.0%); 892 individuals [86.8%] in New York Heart Association class I and II), 197 (19.2%) participated in the medication optimization program, and 831 (80.8%) continued with usual care as directed by their treating clinicians (585 [56.9%] general cardiologists; 443 [43.1%] heart failure specialists). At 3 months, patients participating in the remote intervention experienced significant increases from baseline in use of renin-angiotensin system antagonists (138 [70.1%] to 170 [86.3%]; P < .001) and ß-blockers (152 [77.2%] to 181 [91.9%]; P < .001) but not mineralocorticoid receptor antagonists (51 [25.9%] to 60 [30.5%]; P = .14). Doses for each category of GDMT also increased from baseline in the intervention group. Among the usual-care group, there were no changes from baseline in the proportion of patients receiving GDMT or the dose of GDMT in any category. Conclusions and Relevance: Remote titration of GDMT by navigators using encoded algorithms may represent an efficient, population-level strategy for rapidly closing the gap between guidelines and clinical practice in patients with HFrEF.


Assuntos
Insuficiência Cardíaca/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Estudos de Casos e Controles , Feminino , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Volume Sistólico , Telemedicina
18.
J Gastrointest Surg ; 24(7): 1581-1589, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32410174

RESUMO

BACKGROUND: Long-term complications following pancreatoduodenectomy (PD) can significantly impact quality of life and healthcare utilization. Most reports focus on short-term (within 90 days) PD outcomes; however, the incidence and risk factors for long-term complications (> 90 days) remain to be evaluated. We sought to identify the incidence, outcomes, and risk factors for long-term complications post-PD. METHODS: All PD survivors between 2010 and 2017 were identified from a single-institutional database. Long-term complications (> 90 days post-PD and not resulting from cancer recurrence), including biliary stricture, cholangitis, pancreatitis, peptic ulcer, small bowel obstruction, and incisional hernia, were identified. Logistic regression was used to identify perioperative predictors of long-term complications. RESULTS: Of 906 PDs, 628 long-term survivors met criteria for analysis (mean age of 65.3 years, 47% female). Median follow-up and overall survival were 51.1 months (95% CI 47.6, 55.7) and 68.5 months (95% CI 57.9, 81.4), respectively. A total of 198 (31.5%) experienced at least one long-term complication. Complications included incisional hernia (17.7%), biliary stricture or cholangitis (8.0%), pancreatitis (5.7%), small bowel obstruction (4.3%), and peptic ulcer (3.2%). In total, 108 (17.2%) of the complications required an intervention, nearly half of which were surgical. On multivariable analysis, several predictors of long-term complications were identified: obesity (BMI ≥ 30 kg/m2), postoperative wound infection, prolonged index length of stay, readmission (< 90 days), operative approach (open vs. robotic), and pylorus-preservation. CONCLUSION: Long-term complications occur in nearly a third of PDs and nearly one-fifth of all PDs require re-intervention. Several modifiable predictors of long-term complications were identified.


Assuntos
Hérnia Incisional , Pancreaticoduodenectomia , Idoso , Feminino , Humanos , Incidência , Masculino , Pancreaticoduodenectomia/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Qualidade de Vida , Estudos Retrospectivos , Fatores de Risco
19.
Clin Cardiol ; 43(1): 4-13, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31725920

RESUMO

Although optimal pharmacological therapy for heart failure with reduced ejection fraction (HFrEF) is carefully scripted by treatment guidelines, many eligible patients are not treated with guideline-directed medical therapy (GDMT) in clinical practice. We designed a strategy for remote optimization of GDMT on a population scale in patients with HFrEF leveraging nonphysician providers. An electronic health record-based algorithm was used to identify a cohort of patients with a diagnosis of heart failure (HF) and ejection fraction (EF) ≤ 40% receiving longitudinal follow-up at our center. Those with end-stage HF requiring inotropic support, mechanical circulatory support, or transplantation and those enrolled in hospice or palliative care were excluded. Treating providers were approached for consent to adjust medical therapy according to a sequential, stepped titration algorithm modeled on the current American College of Cardiology (ACC)/American Heart Association (AHA) HF Guidelines within a collaborative care agreement. The program was approved by the institutional review board at Brigham and Women's Hospital with a waiver of written informed consent. All patients provided verbal consent to participate. A navigator then facilitated medication adjustments by telephone and conducted longitudinal surveillance of laboratories, blood pressure, and symptoms. Each titration step was reviewed by a pharmacist with supervision as needed from a nurse practitioner and HF cardiologist. Patients were discharged from the program to their primary cardiologist after achievement of an optimal or maximally tolerated regimen. A navigator-led remote management strategy for optimization of GDMT may represent a scalable population-level strategy for closing the gap between guidelines and clinical practice in patients with HFrEF.


Assuntos
Insuficiência Cardíaca/tratamento farmacológico , Navegação de Pacientes/métodos , Telemedicina/métodos , Idoso , Algoritmos , Feminino , Seguimentos , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/terapia , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Projetos de Pesquisa , Volume Sistólico
20.
Nat Struct Mol Biol ; 26(7): 592-598, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31235909

RESUMO

Glucagon and insulin maintain blood glucose homeostasis and are used to treat hypoglycemia and hyperglycemia, respectively, in patients with diabetes. Whereas insulin is stable for weeks in its solution formulation, glucagon fibrillizes rapidly at the acidic pH required for solubility and is therefore formulated as a lyophilized powder that is reconstituted in an acidic solution immediately before use. Here we use solid-state NMR to determine the atomic-resolution structure of fibrils of synthetic human glucagon grown at pharmaceutically relevant low pH. Unexpectedly, two sets of chemical shifts are observed, indicating the coexistence of two ß-strand conformations. The two conformations have distinct water accessibilities and intermolecular contacts, indicating that they alternate and hydrogen bond in an antiparallel fashion along the fibril axis. Two antiparallel ß-sheets assemble with symmetric homodimer cross sections. This amyloid structure is stabilized by numerous aromatic, cation-π, polar and hydrophobic interactions, suggesting mutagenesis approaches to inhibit fibrillization could improve this important drug.


Assuntos
Amiloide/química , Glucagon/química , Sequência de Aminoácidos , Amiloide/ultraestrutura , Humanos , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Ressonância Magnética Nuclear Biomolecular , Fragmentos de Peptídeos/química , Conformação Proteica em Folha beta , Multimerização Proteica , Solubilidade
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