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1.
Open Forum Infect Dis ; 11(6): ofae103, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38887478

RESUMO

Combination antifungal therapy for invasive mucormycosis remains controversial and is inconsistently defined in prior studies. In a cohort of patients with immunocompromised status and invasive mucormycosis, we found no difference in 6-week mortality with up-front or salvage combination therapy as compared with monotherapy.

2.
Adv Sci (Weinh) ; 10(30): e2303665, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37718654

RESUMO

A transdermal patch that delivers insulin at high glucose concentrations can offer tremendous advantages to ease the concern of safety and improve the quality of life for people with diabetes. Herein, a novel self-crosslinkable and glucose-responsive polymer-based microneedle patch (MN) is designed to deliver insulin at hyperglycemia. The microneedle patch is made of hyaluronic acid polymers functionalized with dopamine and 4-amino-3-fluorophenylboronic acid (AFBA) that can be quickly crosslinked upon mixing of the polymer solutions in the absence of any chemicalcrosslinking agents or organic solvents. The catechol groups in the dopamine (DA) units form covalent crosslinkages among themselves by auto-oxidation and dynamic crosslink with phenylboronic acid (PBA) via complexation. The reversible crosslinkages between catechol and boronate decrease with increasing glucose concentration leading to higher swelling and faster insulin release at hyperglycemia as compared to euglycemia. Such superior glucose-responsive properties are demonstrated by in vitro analyses and in vivo efficacy studies. The hydrogel polymers also preserve native structure and bioactivity of insulin, attributable to the interaction of hyaluronic acid (HA) with insulin molecules, as revealed by experiments and molecular dynamics simulations. The simplicity in the design and fabrication process, and glucose-responsiveness in insulin delivery impart the matrix microneedle (mMN) patch great potential for clinical translation.


Assuntos
Diabetes Mellitus Experimental , Hiperglicemia , Animais , Humanos , Insulina/química , Glicemia/análise , Ácido Hialurônico/química , Polímeros/química , Dopamina , Qualidade de Vida , Diabetes Mellitus Experimental/tratamento farmacológico , Glucose
3.
Diabetes ; 72(10): 1460-1469, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37494660

RESUMO

Verapamil promotes functional ß-cell mass and improves glucose homeostasis in diabetic mice and humans with type 1 diabetes (T1D). Now, our global proteomics analysis of serum from subjects with T1D at baseline and after 1 year of receiving verapamil or placebo revealed IGF-I as a protein with significantly changed abundance over time. IGF-I, which promotes ß-cell survival and insulin secretion, decreased during disease progression, and this decline was blunted by verapamil. In addition, we found that verapamil reduces ß-cell expression of IGF-binding protein 3 (IGFBP3), whereas IGFBP3 was increased in human islets exposed to T1D-associated cytokines and in diabetic NOD mouse islets. IGFBP3 binds IGF-I and blocks its downstream signaling, which has been associated with increased ß-cell apoptosis and impaired glucose homeostasis. Consistent with the downregulation of IGFBP3, we have now discovered that verapamil increases ß-cell IGF-I signaling and phosphorylation/activation of the IGF-I receptor (IGF1R). Moreover, we found that thioredoxin-interacting protein (TXNIP), a proapoptotic factor downregulated by verapamil, promotes IGFBP3 expression and inhibits the phosphorylation/activation of IGF1R. Thus, our results reveal IGF-I signaling as yet another previously unappreciated pathway affected by verapamil and TXNIP that may contribute to the beneficial verapamil effects in the context of T1D. ARTICLE HIGHLIGHTS: Verapamil prevents the decline of IGF-I in subjects with type 1 diabetes (T1D). Verapamil decreases the expression of ß-cell IGF-binding protein 3 (IGFBP3), whereas IGFBP3 is increased in human and mouse islets under T1D conditions. Verapamil promotes ß-cell IGF-I signaling by increasing phosphorylation of IGF-I receptor and its downstream effector AKT. Thioredoxin-interacting protein (TXNIP) increases IGFBP3 expression and inhibits the phosphorylation/activation of IGF1R in ß-cells. Regulation of IGFBP3 and IGF-I signaling by verapamil and TXNIP may contribute to the beneficial verapamil effects in the context of T1D.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Humanos , Camundongos , Animais , Diabetes Mellitus Tipo 1/tratamento farmacológico , Fator de Crescimento Insulin-Like I/metabolismo , Receptor IGF Tipo 1/metabolismo , Verapamil/farmacologia , Verapamil/uso terapêutico , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Diabetes Mellitus Experimental/metabolismo , Camundongos Endogâmicos NOD , Tiorredoxinas/metabolismo , Glucose
4.
J Neurosurg Spine ; 39(3): 411-418, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37327146

RESUMO

OBJECTIVE: Chordomas are most frequently found in the sacrum, vertebral column, and skull base. Achieving gross-total resection (GTR) has been shown to optimize overall survival (OS); however, the efficacy of radiotherapy (RT) for patients with GTR is currently not well understood. Given that RT may negatively impact patient quality of life, the aim of this study was to evaluate the utility of RT for improving OS in patients who have undergone GTR of spinal chordoma through analysis of the national Surveillance, Epidemiology, and End Results (SEER) database. METHODS: The SEER database (1975-2018) was queried for all adult patients (≥ 21 years) who underwent GTR for spinal chordoma. Bivariate analysis was conducted using chi-square testing for categorical variables, and the log-rank test was performed to find the associations of clinical variables with OS. Cox proportional hazards models were generated for multivariate analyses of the associations among clinical variables and OS. RESULTS: A total of 263 spinal chordomas that underwent GTR were identified. The mean age of all included patients was 58.72 years, and 63.9% of patients were male. In addition, 0.4% had dedifferentiated histology. The mean follow-up was 75.54 months. Of all patients, 152 (57.8%) received no RT and 111 (42.2%) received RT. Patients with sacral tumor location (80.9% vs 51.4%, p < 0.001) were more likely not to undergo RT when compared to patients with vertebral column location. In multivariate analysis, only age ≥ 65 years was associated with poorer OS (HR 3.16, CI 1.54-5.61, p < 0.001). RT did not have a statistically significant association with OS. CONCLUSIONS: RT after GTR of chordoma did not improve OS among SEER chordoma patients to a value that achieved statistical significance. Additional multicenter prospective studies are needed to determine the true efficacy of RT after GTR of spinal chordoma.


Assuntos
Cordoma , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Feminino , Cordoma/radioterapia , Cordoma/cirurgia , Cordoma/patologia , Qualidade de Vida , Radioterapia Adjuvante , Sacro/cirurgia , Sacro/patologia , Estudos Retrospectivos , Resultado do Tratamento
5.
J Antimicrob Chemother ; 78(4): 1009-1014, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-36879495

RESUMO

BACKGROUND: The role of piperacillin/tazobactam for treatment of serious infections due to AmpC-producing organisms remains debatable, particularly in immunocompromised patients. METHODS: This was a retrospective cohort study in immunocompromised patients that investigated the effect of definitive treatment with either piperacillin/tazobactam versus cefepime or carbapenems for bacteraemia caused by cefoxitin-non-susceptible Enterobacterales. The primary endpoint was a composite of clinical and microbiological failure. A logistic regression model was constructed to assess the impact of definitive treatment choice on the primary endpoint. RESULTS: A total of 81 immunocompromised patients with blood cultures positive for cefoxitin-non-susceptible Enterobacterales were included for analysis. There was more microbiological failure in the piperacillin/tazobactam arm compared with the cefepime/carbapenem arm (11.4% versus 0.0%, P = 0.019). Definitive treatment with cefepime or a carbapenem was associated with a decreased odds of clinical or microbiological failure (OR 0.303, 95% CI 0.093-0.991, P = 0.048) when controlling for baseline characteristics. CONCLUSIONS: In immunocompromised patients with bacteraemia due to cefoxitin-non-susceptible Enterobacterales, definitive treatment with piperacillin/tazobactam was associated with an increased risk of microbiological failure and higher odds of clinical or microbiological failure compared with cefepime or carbapenems.


Assuntos
Bacteriemia , Enterobacter aerogenes , Morganella morganii , Humanos , Cefepima/uso terapêutico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Carbapenêmicos/uso terapêutico , Cefoxitina/farmacologia , Cefoxitina/uso terapêutico , Citrobacter freundii , Serratia marcescens , Enterobacter cloacae , Estudos Retrospectivos , Combinação Piperacilina e Tazobactam/uso terapêutico , Bacteriemia/tratamento farmacológico , Bacteriemia/microbiologia , beta-Lactamases , Testes de Sensibilidade Microbiana
6.
J Clin Oncol ; 41(11): 2007-2019, 2023 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-36521097

RESUMO

PURPOSE: This randomized, open-label trial compared the efficacy and safety of adjuvant nab-paclitaxel + gemcitabine with those of gemcitabine for resected pancreatic ductal adenocarcinoma (ClinicalTrials.gov identifier: NCT01964430). METHODS: We assigned 866 treatment-naive patients with pancreatic ductal adenocarcinoma to nab-paclitaxel (125 mg/m2) + gemcitabine (1,000 mg/m2) or gemcitabine alone to one 30-40 infusion on days 1, 8, and 15 of six 28-day cycles. The primary end point was independently assessed disease-free survival (DFS). Additional end points included investigator-assessed DFS, overall survival (OS), and safety. RESULTS: Two hundred eighty-seven of 432 patients and 310 of 434 patients completed nab-paclitaxel + gemcitabine and gemcitabine treatment, respectively. At primary data cutoff (December 31, 2018; median follow-up, 38.5 [interquartile range [IQR], 33.8-43 months), the median independently assessed DFS was 19.4 (nab-paclitaxel + gemcitabine) versus 18.8 months (gemcitabine; hazard ratio [HR], 0.88; 95% CI, 0.729 to 1.063; P = .18). The median investigator-assessed DFS was 16.6 (IQR, 8.4-47.0) and 13.7 (IQR, 8.3-44.1) months, respectively (HR, 0.82; 95% CI, 0.694 to 0.965; P = .02). The median OS (427 events; 68% mature) was 40.5 (IQR, 20.7 to not reached) and 36.2 (IQR, 17.7-53.3) months, respectively (HR, 0.82; 95% CI, 0.680 to 0.996; P = .045). At a 16-month follow-up (cutoff, April 3, 2020; median follow-up, 51.4 months [IQR, 47.0-57.0]), the median OS (511 events; 81% mature) was 41.8 (nab-paclitaxel + gemcitabine) versus 37.7 months (gemcitabine; HR, 0.82; 95% CI, 0.687 to 0.973; P = .0232). At the 5-year follow-up (cutoff, April 9, 2021; median follow-up, 63.2 months [IQR, 60.1-68.7]), the median OS (555 events; 88% mature) was 41.8 versus 37.7 months, respectively (HR, 0.80; 95% CI, 0.678 to 0.947; P = .0091). Eighty-six percent (nab-paclitaxel + gemcitabine) and 68% (gemcitabine) of patients experienced grade ≥ 3 treatment-emergent adverse events. Two patients per study arm died of treatment-emergent adverse events. CONCLUSION: The primary end point (independently assessed DFS) was not met despite favorable OS seen with nab-paclitaxel + gemcitabine.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Gencitabina , Desoxicitidina/efeitos adversos , Carcinoma Ductal Pancreático/tratamento farmacológico , Neoplasias Pancreáticas/tratamento farmacológico , Albuminas/efeitos adversos , Paclitaxel/efeitos adversos , Adjuvantes Imunológicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Pancreáticas
7.
J Neurosurg ; 138(5): 1227-1234, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36208433

RESUMO

OBJECTIVE: Surgical site infections (SSIs) burden patients and healthcare systems, often requiring additional intervention. The objective of this study was to identify the relationship between preoperative predictors inclusive of scalp incision type and postoperative SSI following glioblastoma resection. METHODS: The authors retrospectively reviewed cases of glioblastoma resection performed at their institution from December 2006 to December 2019 and noted preoperative demographic and clinical presentations, excluding patients missing these data. Preoperative nutritional indices were available for a subset of cases. Scalp incisions were categorized as linear/curvilinear, reverse question mark, trapdoor, or frontotemporal. Patients were dichotomized by SSI incidence. Multivariable logistic regression was used to determine predictors of SSI. RESULTS: A total of 911 cases of glioblastoma resection were identified, 30 (3.3%) of which demonstrated postoperative SSI. There were no significant differences in preoperative malnutrition or number of surgeries between SSI and non-SSI cases. The SSI cases had a significantly lower preoperative Karnofsky Performance Status (KPS) than the non-SSI cases (63.0 vs 75.1, p < 0.0001), were more likely to have prior radiation history (43.3% vs 26.4%, p = 0.042), and were more likely to have received steroids both preoperatively and postoperatively (83.3% vs 54.5%, p = 0.002). Linear/curvilinear incisions were more common in non-SSI than in SSI cases (56.9% vs 30.0%, p = 0.004). Trapdoor scalp incisions were more frequent in SSI than non-SSI cases (43.3% vs 24.2%, p = 0.012). On multivariable analysis, a lower preoperative KPS (OR 1.04, 95% CI 1.02-1.06), a trapdoor scalp incision (OR 3.34, 95% CI 1.37-8.49), and combined preoperative and postoperative steroid administration (OR 3.52, 95% CI 1.41-10.7) were independently associated with an elevated risk of postoperative SSI. CONCLUSIONS: The study findings indicated that SSI risk following craniotomy for glioblastoma resection may be elevated in patients with a low preoperative KPS, a trapdoor scalp incision during surgery, and steroid treatment both preoperatively and postoperatively. These data may help guide future operative decision-making for these patients.


Assuntos
Glioblastoma , Infecção da Ferida Cirúrgica , Humanos , Infecção da Ferida Cirúrgica/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Craniotomia
8.
Endocrinology ; 163(11)2022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-35957590

RESUMO

Thioredoxin-interacting protein (TXNIP) has emerged as a key factor in pancreatic beta cell biology, and its upregulation by glucose and diabetes contributes to the impairment in functional beta cell mass and glucose homeostasis. In addition, beta cell deletion of TXNIP protects against diabetes in different mouse models. However, while TXNIP is ubiquitously expressed, its role in pancreatic alpha cells has remained elusive. We generated an alpha cell TXNIP knockout (aTKO) mouse and assessed the effects on glucose homeostasis. While no significant changes were observed on regular chow, after a 30-week high-fat diet, aTKO animals showed improvement in glucose tolerance and lower blood glucose levels compared to their control littermates. Moreover, in the context of streptozotocin (STZ)-induced diabetes, aTKO mice showed significantly lower blood glucose levels compared to controls. While serum insulin levels were reduced in both control and aTKO mice, STZ-induced diabetes significantly increased glucagon levels in control mice, but this effect was blunted in aTKO mice. Moreover, glucagon secretion from aTKO islets was >2-fold lower than from control islets, while insulin secretion was unchanged in aTKO islets. At the same time, no change in alpha cell or beta cell numbers or mass was observed, and glucagon and insulin expression and content were comparable in isolated islets from aTKO and control mice. Thus together the current studies suggest that downregulation of alpha cell TXNIP is associated with reduced glucagon secretion and that this may contribute to the glucose-lowering effects observed in diabetic aTKO mice.


Assuntos
Diabetes Mellitus Experimental , Células Secretoras de Glucagon , Hiperglicemia , Células Secretoras de Insulina , Pancreatopatias , Animais , Glicemia/metabolismo , Proteínas de Transporte , Diabetes Mellitus Experimental/metabolismo , Glucagon/metabolismo , Células Secretoras de Glucagon/metabolismo , Glucose/metabolismo , Hiperglicemia/genética , Hiperglicemia/metabolismo , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Camundongos , Estreptozocina , Tiorredoxinas
10.
Genetics ; 221(4)2022 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-35731216

RESUMO

Parasitic nematodes are major human and agricultural pests, and benzimidazoles are amongst the most important broad-spectrum anthelmintic drug class used for their control. Benzimidazole resistance is now widespread in many species of parasitic nematodes in livestock globally and an emerging concern for the sustainable control of human soil-transmitted helminths. ß-tubulin is the major benzimidazole target, although other genes may influence resistance. Among the 6 Caenorhabditis elegans ß-tubulin genes, loss of ben-1 causes resistance without other apparent defects. Here, we explored the genetics of C. elegans ß-tubulin genes in relation to the response to the benzimidazole derivative albendazole. The most highly expressed ß-tubulin isotypes, encoded by tbb-1 and tbb-2, were known to be redundant with each other for viability, and their products are predicted not to bind benzimidazoles. We found that tbb-2 mutants, and to a lesser extent tbb-1 mutants, were hypersensitive to albendazole. The double mutant tbb-2 ben-1 is uncoordinated and short, resembling the wild type exposed to albendazole, but the tbb-1 ben-1 double mutant did not show the same phenotypes. These results suggest that tbb-2 is a modifier of albendazole sensitivity. To better understand how BEN-1 mutates to cause benzimidazole resistance, we isolated mutants resistant to albendazole and found that 15 of 16 mutations occurred in the ben-1 coding region. Mutations ranged from likely nulls to hypomorphs, and several corresponded to residues that cause resistance in other organisms. Null alleles of ben-1 are albendazole-resistant and BEN-1 shows high sequence identity with tubulins from other organisms, suggesting that many amino acid changes could cause resistance. However, our results suggest that missense mutations conferring resistance are not evenly distributed across all possible conserved sites. Independent of their roles in benzimidazole resistance, tbb-1 and tbb-2 may have specialized functions as null mutants of tbb-1 or tbb-2 were cold or heat sensitive, respectively.


Assuntos
Anti-Helmínticos , Tubulina (Proteína) , Albendazol/metabolismo , Albendazol/farmacologia , Animais , Anti-Helmínticos/farmacologia , Benzimidazóis/farmacologia , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Resistência a Medicamentos/genética , Humanos , Microtúbulos/metabolismo , Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismo , Moduladores de Tubulina
11.
Mol Pharm ; 19(6): 1722-1765, 2022 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-35587783

RESUMO

Globally, a rising burden of complex diseases takes a heavy toll on human lives and poses substantial clinical and economic challenges. This review covers nanomedicine and nanotechnology-enabled advanced drug delivery systems (DDS) designed to address various unmet medical needs. Key nanomedicine and DDSs, currently employed in the clinic to tackle some of these diseases, are discussed focusing on their versatility in diagnostics, anticancer therapy, and diabetes management. First-hand experiences from our own laboratory and the work of others are presented to provide insights into strategies to design and optimize nanomedicine- and nanotechnology-enabled DDS for enhancing therapeutic outcomes. Computational analysis is also briefly reviewed as a technology for rational design of controlled release DDS. Further explorations of DDS have illuminated the interplay of physiological barriers and their impact on DDS. It is demonstrated how such delivery systems can overcome these barriers for enhanced therapeutic efficacy and how new perspectives of next-generation DDS can be applied clinically.


Assuntos
Nanomedicina , Nanopartículas , Sistemas de Liberação de Medicamentos , Humanos , Nanotecnologia
12.
ACS Appl Mater Interfaces ; 14(18): 20576-20590, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35471922

RESUMO

Hypoglycemia is a major complication associated with insulin therapy in people with diabetes that could cause life-threatening conditions if untreated. Glucagon, a counter-acting hormone, is thus administered for rescue of severe hypoglycemia. However, due to the instability of glucagon, only limited medications are available for emergency use, which are unsuitable for patients with hypoglycemia unawareness or with the inability to self-administer, especially during sleep (namely, nocturnal hypoglycemia). To prevent unattended and extended hypoglycemia, we designed a "smart" composite microneedle (cMN) patch capable of stabilizing glucagon, sensing hypoglycemia, and delivering glucagon automatically on demand. In this design, native glucagon was encapsulated in glucose-responsive microgels containing a glucagon-stabilizing component rationally selected by molecular dynamics (MD) simulation. A cMN patch was then prepared by incorporating the glucagon microgels with poly(methyl vinyl ether-alt-maleic anhydride) (PMVE-MAH) and poly(ethylene glycol) (PEG) followed by thermal cross-linking. The rationally designed zwitterionic polymer-based microgels preserved the native structure of glucagon and prevented heat-induced fibrillation evidenced by RP-HPLC, circular dichroism, and transmission electron microscopy. MD simulations suggested that the polymeric microgels stabilized glucagon by inhibition of oligomer formation via peptide-polymer noncovalent interactions. The polymer formed multiple hydrogen bonds with the polar and charged amino acid residues of the glucagon molecule, shielding the peptide surface from aggregation. In vivo efficacy studies using streptozotocin-induced type 1 diabetic (T1D) rats demonstrated that the glucagon-loaded cMN patch could prevent hypoglycemia induced by insulin overdose during a 12 h period. The results suggest that this new glucagon "smart" patch may be a promising system for improving the quality of life of those suffering from nocturnal hypoglycemia and hypoglycemia unawareness.


Assuntos
Hipoglicemia , Microgéis , Animais , Glicemia/metabolismo , Glucagon/efeitos adversos , Glucagon/metabolismo , Humanos , Hipoglicemia/induzido quimicamente , Hipoglicemia/tratamento farmacológico , Hipoglicemia/prevenção & controle , Insulina/química , Insulina/uso terapêutico , Simulação de Dinâmica Molecular , Polímeros/uso terapêutico , Qualidade de Vida , Ratos
13.
Proc Natl Acad Sci U S A ; 119(11): e2116254119, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35254895

RESUMO

SignificanceTranscription-coupled repair (TCR) involves four core proteins: CSA, CSB, USP7, and UVSSA. CSA and CSB are mutated in the severe human neurocutaneous disease Cockayne syndrome. In contrast UVSSA is a mild photosensitive disease in which a mutated protein sequence prevents recruitment of USP7 protease to deubiquitinate and stabilize CSB. We deleted the UVSSA protein using CRISPR-Cas9 in an aneuploid cell line, HEK293, and determined the functional consequences. The knockout cell line was sensitive to transcription-blocking lesions but not sensitive to oxidative agents or PARP inhibitors, unlike CSB. Knockout of UVSSA also activated ATM, like CSB, in transcription-arrested cells. The phenotype of UVSSA, especially its rarity, suggests that many TCR-deficient patients and tumors fail to be recognized clinically.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Proteínas de Transporte/metabolismo , Reparo do DNA , Homeostase , Transdução de Sinais , Transcrição Gênica , Alquilantes/farmacologia , Sequência de Aminoácidos , Proteínas de Transporte/química , Dano ao DNA/efeitos dos fármacos , Dano ao DNA/efeitos da radiação , Células HEK293 , Humanos , Mutagênicos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Raios Ultravioleta
14.
Biophys J ; 121(6): 1105-1114, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35120902

RESUMO

Synthetic ion channels based on benzo(crown-ether) compounds have been previously reported to function as ion-selective channels in planar lipid bilayers, with hydrogen bonding networks implicated in the formation of self-aggregated complexes. Herein, we report the synthesis and characterization of two new families of benzo(crown-ether) compounds, termed monoacylated and monoalkylated benzo(crown-ethers) (MABCE), both of which lack hydrogen bond donors. Depending on the length of alkyl chain substituent and the size of macrocycle, MABCE compounds inhibit bacterial growth and transport ions across biological membranes. Single-channel recordings show that the activity is higher in the presence of K+ as compared with Na+; however, under bionic conditions, open channels do not exhibit any preference between the two ions. These findings reveal that the ionic preference of benzo(crown-ether) compounds is either due to the regulation of assembly of ion-conducting supramolecular complexes or its membrane insertion by cations, as opposed to ion-selective transport through these scaffolds. Furthermore, our data show that the H-bonding network is not needed to form these assemblies in the membrane.


Assuntos
Éteres de Coroa , Cátions , Éteres de Coroa/química , Ligação de Hidrogênio , Canais Iônicos/química , Bicamadas Lipídicas/química
15.
Drug Deliv Transl Res ; 12(4): 792-804, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-33683625

RESUMO

Hypoglycemia is a serious and potentially fatal complication experienced by people with insulin-dependent diabetes. The complication is usually caused by insulin overdose, skipping meals, and/or excessive physical activities. In type 1 diabetes (T1D), on top of impaired pancreatic α-cells, excessive levels of somatostatin from δ-cells further inhibit glucagon secretion to counteract overdosed insulin. Herein, we aimed to develop a microneedle (MN) patch for transdermal delivery of a peptide (PRL-2903) that antagonizes somatostatin receptor type 2 (SSTR2) in α-cells. First, we investigated the efficacy of subcutaneously administered PRL-2903 and identified the optimal dose (i.e., the minimum effective dose) and treatment scheduling (i.e., the best administration time for hypoglycemia prevention) in a T1D rat model. We then designed an MN patch using a hyaluronic acid (HA)-based polymer. The possible effect of the polymer on stabilizing the native structure of PRL-2903 was studied by molecular dynamics (MD) simulations. The results showed that the HA-based polymer could stabilize the PRL-2903 structure by restricting water molecules, promoting intra-molecular H-bonding, and constraining torsional angles of important bonds. In vivo studies with an overdose insulin challenge revealed that the PRL-2903-loaded MN patch effectively increased the plasma glucagon level, restored the counter-regulation of blood glucose concentration, and prevented hypoglycemia. The proposed MN patch is the first demonstration of a transdermal microneedle patch designed to deliver an SSTR2 antagonist for the prevention of hypoglycemia. This counter-regulatory peptide delivery system may be applied alongside with insulin delivery systems to provide a more effective and safer treatment for people with insulin-dependent diabetes.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Hipoglicemia , Animais , Glicemia , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 1/tratamento farmacológico , Sistemas de Liberação de Medicamentos/métodos , Glucagon , Humanos , Hipoglicemia/induzido quimicamente , Hipoglicemia/tratamento farmacológico , Hipoglicemia/prevenção & controle , Insulina/química , Agulhas , Polímeros/uso terapêutico , Ratos , Receptores de Somatostatina , Tecnologia , Adesivo Transdérmico
16.
Front Oncol ; 11: 696512, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34552864

RESUMO

BACKGROUND: Histone deacetylase (HDAC) overexpression has been documented in various cancers and may be associated with worse outcomes. Data from early-phase studies of advanced non-small cell lung cancer (NSCLC) suggest encouraging antitumor activity with the combination of an HDAC inhibitor and either platinum-based chemotherapy or an EGFR inhibitor; however, toxicity is a limiting factor in the use of pan-HDAC inhibitors. Selective inhibition of HDAC6 may represent a potential therapeutic target and preclinical studies revealed immunomodulatory effects with HDAC6 inhibition, suggesting the potential for combination with immune checkpoint inhibitors. This phase Ib, multicenter, single-arm, open-label, dose-escalation study investigated the HDAC6 inhibitor ACY-241 (citarinostat) plus nivolumab in patients with previously treated advanced NSCLC who had not received a prior HDAC or immune checkpoint inhibitor. METHODS: The orally administered ACY-241 dose was escalated (180, 360, or 480 mg once daily). Nivolumab was administered at 240 mg (day 15 of cycle 1, then every 2 weeks thereafter). The primary endpoint was to determine the maximum tolerated dose (MTD) of ACY-241 plus nivolumab. Secondary endpoints included safety, tolerability, and preliminary antitumor activity. Pharmacodynamics was an exploratory endpoint. RESULTS: A total of 18 patients were enrolled, with 17 patients treated. No dose-limiting toxicities (DLTs) occurred with ACY-241 at 180 or 360 mg; 2 DLTs occurred at 480 mg. The MTD of ACY-241 was 360 mg. The most common grade ≥ 3 treatment-emergent adverse events were dyspnea (n = 3; 18%) and pneumonia (n = 3; 18%). At the 180-mg dose, 1 complete response and 2 partial responses (PRs) were observed. At the 360-mg dose, 3 PRs were observed; 1 patient achieved stable disease (SD) and 1 experienced progressive disease (PD). At the 480-mg dose, no responses were observed; 1 patient achieved SD and 3 experienced PD. Acetylation analyses revealed transient increases in histone and tubulin acetylation levels following treatment. An increase in infiltrating total CD3+ T cells was observed following treatment. CONCLUSIONS: The study identified an MTD for ACY-241 plus nivolumab and the data suggest that the combination may be feasible in patients with advanced NSCLC. Responses were observed in patients with advanced NSCLC. CLINICAL TRIAL REGISTRATION: https://clinicaltrials.gov/ct2/show/NCT02635061 (identifier, NCT02635061).

17.
Adv Exp Med Biol ; 1322: 285-312, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34258745

RESUMO

Nowadays, many viral infections have emerged and are taking a huge toll on human lives globally. Meanwhile, viral resistance to current drugs has drastically increased. Hence, there is a pressing need to design potent broad-spectrum antiviral agents to treat a variety of viral infections and overcome viral resistance. Covalent inhibitors have the potential to achieve both goals owing to their biochemical efficiency, prolonged duration of action, and the capability to inhibit shallow, solvent-exposed substrate-binding domains. In this chapter, we review the structures, activities, and inhibition mechanisms of covalent inhibitors against severe acute respiratory syndrome coronavirus 2, dengue virus, enterovirus, hepatitis C virus, human immunodeficiency virus, and influenza viruses. We also discuss the application of in silico study in covalent inhibitor design.


Assuntos
COVID-19 , Hepatite C , Viroses , Antivirais/farmacologia , Antivirais/uso terapêutico , Hepatite C/tratamento farmacológico , Humanos , SARS-CoV-2 , Viroses/tratamento farmacológico
18.
Clin Pharmacol Ther ; 110(3): 733-740, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34114646

RESUMO

The association between the c.521T>C variant allele in SLCO1B1 (reference single nucleotide polymorphism (rs)4149056) and simvastatin-induced myotoxicity was discovered over a decade ago; however, whether this relationship represents a class effect is still not fully known. The aim of this study was to investigate the relationship between rs4149056 genotype and statin-induced myotoxicity in patients taking atorvastatin and lovastatin. Study participants were from the Genetic Epidemiology Research on Adult Health and Aging (GERA) cohort. A total of 233 statin-induced myopathy + rhabdomyolysis cases met the criteria for inclusion and were matched to 2,342 controls. To validate the drug response phenotype, we replicated the previously established association between rs4149056 genotype and simvastatin-induced myotoxicity. In particular, compared with homozygous T allele carriers, there was a significantly increased risk of simvastatin-induced myopathy + rhabdomyolysis in homozygous carriers of the C allele (CC vs. TT, odds ratio [OR] 4.62, 95% confidence interval [CI] 1.58-11.90, P = 0.003). For lovastatin users, homozygous carriers of the C allele were also at increased risk of statin-induced myopathy + rhabdomyolysis (CC vs. TT, OR 4.49, 95% CI 1.68-10.80, P = 0.001). In atorvastatin users, homozygous carriers of the C allele were twice as likely to experience statin-induced myopathy, though this association did not achieve statistical significance (CC vs. TT, OR 2.00, 95% CI 0.44-6.59, P = 0.30). In summary, our findings suggest that the association of rs4149056 with simvastatin-related myotoxicity may also extend to lovastatin. More data is needed to determine the extent of the association in atorvastatin users. Altogether, these data expand the evidence base for informing guidelines of pharmacogenetic-based statin prescribing practices.


Assuntos
Atorvastatina/efeitos adversos , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Transportador 1 de Ânion Orgânico Específico do Fígado/genética , Lovastatina/efeitos adversos , Miotoxicidade/etiologia , Miotoxicidade/genética , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/genética , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , Masculino , Doenças Musculares/induzido quimicamente , Doenças Musculares/genética , Fenótipo , Polimorfismo de Nucleotídeo Único/genética
19.
Ann Surg Oncol ; 28(12): 7545-7554, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33813673

RESUMO

BACKGROUND: Although the European Organisation for Research and Treatment of Cancer (EORTC) QLQ-PAN26 is widely used to assess health-related quality of life (HRQoL), its group-level minimal important difference (MID) and individual-level responder definition (RD) are not established; we calculated MID and RD using HRQoL data from the APACT trial in patients with surgically resected pancreatic cancer who received adjuvant chemotherapy. METHODS: HRQoL was assessed using EORTC QLQ-C30 and QLQ-PAN26 at baseline, during treatment, at end of treatment, and during follow-up. Distribution-based MIDs were estimated using 0.5 × baseline standard deviation (SD) and reliability-based (intraclass correlation) standard error of measurement (SEM). Anchor-based MIDs and RDs (anchor, QLQ-C30 overall health) were estimated using a linear mixed model. RESULTS: Overall, 772 patients completed the baseline assessment. Distribution-based MIDs (0.5 × SD) for QLQ-PAN26 scales ranged from 12 to 13, except hepatic symptoms (≈8), pancreatic pain (≈10), and sexual dysfunction (≈17); those for stand-alone items ranged from 12 to 16. The SEM values were similar. Among scales/items sufficiently correlated (r > 0.30) with the anchor, MIDs ranged from 5 to 9. Within-patient QLQ-PAN26 RD estimates varied by direction (deterioration vs. improvement) and scale/item, but all values were lower than the true possible within-patient change (e.g. 16.7 points for a two-item scale) given a one-category change on the raw scale. CONCLUSIONS: Compared with distribution-based MIDs, anchor-based MIDs were twice as sensitive in detecting group-level changes in QLQ-PAN26 scales/items. For interpreting clinically meaningful change, RDs cannot be less than the true minimum of the scale. The group-level MID may help clinicians/researchers interpret HRQoL changes. TRIAL REGISTRATION: ClinicalTrials.gov NCT01964430; Eudra CT 2013-003398-91.


Assuntos
Adenocarcinoma , Neoplasias Pancreáticas , Adenocarcinoma/cirurgia , Humanos , Neoplasias Pancreáticas/cirurgia , Qualidade de Vida , Reprodutibilidade dos Testes , Inquéritos e Questionários
20.
Front Oncol ; 11: 786120, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35070991

RESUMO

BACKGROUND: Citarinostat (CC-96241; previously ACY-241), an oral inhibitor of histone deacetylases (HDACs) with selectivity for HDAC6, has demonstrated synergistic anticancer activity with paclitaxel in multiple solid tumor models. Combination therapy using citarinostat with paclitaxel was evaluated in this phase Ib 3 + 3 dose-escalation study in patients with advanced solid tumors. METHODS: Patients with previously treated advanced solid tumors received citarinostat 180, 360, or 480 mg once daily on days 1 to 21 plus paclitaxel 80 mg/m2 on days 1, 8, and 15 of 28-day cycles until disease progression or unacceptable toxicity. The primary endpoint was determination of the maximum tolerated dose (MTD). Secondary endpoints included safety, antitumor activity, pharmacokinetics, and pharmacodynamics. RESULTS: Twenty patients were enrolled and received study treatment; 15 had received prior taxane therapy. No dose-limiting toxicities were reported at any dose; therefore, the MTD was not identified. Citarinostat 360 vs 480 mg was associated with reduced incidence and severity of neutropenia. Three patients experienced a confirmed partial response and 13 achieved stable disease. Pharmacokinetic parameters were linear up to citarinostat 360 mg, the dose at which the highest levels of histone and tubulin acetylation were observed in peripheral blood mononuclear cells. CONCLUSIONS: The combination of citarinostat plus paclitaxel showed an acceptable safety profile, with no unexpected or dose-limiting toxicities and potential evidence of antitumor activity in patients with heavily pretreated advanced solid tumors. Citarinostat 360 mg once daily is considered the recommended phase II dose for use in combination with paclitaxel 80 mg/m2 every 3 of 4 weeks. This trial is registered on ClinicalTrials.gov (NCT02551185).

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