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1.
Biochemistry ; 62(7): 1321-1329, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-36883372

RESUMO

The Myb transcription factor is involved in the proliferation of hematopoietic cells, and deregulation of its expression can lead to cancers such as leukemia. Myb interacts with various proteins, including the histone acetyltransferases p300 and CBP. Myb binds to a small domain of p300, the KIX domain (p300KIX), and inhibiting this interaction is a potential new drug discovery strategy in oncology. The available structures show that Myb binds to a very shallow pocket of the KIX domain, indicating that it might be challenging to identify inhibitors of this interaction. Here, we report the design of Myb-derived peptides which interact with p300KIX. We show that by mutating only two Myb residues that bind in or near a hotspot at the surface of p300KIX, it is possible to obtain single-digit nanomolar peptidic inhibitors of the Myb/p300KIX interaction that bind 400-fold tighter to p300KIX than wildtype Myb. These findings suggest that it might also be possible to design potent low molecular-weight compounds to disrupt the Myb/p300KIX interaction.


Assuntos
Proteína p300 Associada a E1A , Peptídeos , Proteínas Proto-Oncogênicas c-myb , Peptídeos/farmacologia , Ligação Proteica , Proteínas Proto-Oncogênicas c-myb/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-myb/química , Proteína p300 Associada a E1A/antagonistas & inibidores , Proteína p300 Associada a E1A/química
2.
BMC Genomics ; 23(1): 672, 2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36167494

RESUMO

INTRODUCTION: Infectious diseases are common causes of morbidity and mortality worldwide. Susceptibility to infection is highly heritable; however, little has been done to identify the genetic determinants underlying common infectious diseases. One GWAS was performed using 23andMe information about self-reported infections; we set out to confirm previous loci and identify new ones using medically diagnosed infections. METHODS: We used the electronic health record (EHR)-based biobank at Vanderbilt and diagnosis codes to identify cases of 12 infectious diseases in white patients: urinary tract infection, pneumonia, chronic sinus infections, otitis media, candidiasis, streptococcal pharyngitis, herpes zoster, herpes labialis, hepatitis B, infectious mononucleosis, tuberculosis (TB) or a positive TB test, and hepatitis C. We selected controls from patients with no diagnosis code for the candidate disease and matched by year of birth, sex, and calendar year at first and last EHR visits. We conducted GWAS using SAIGE and transcriptome-wide analysis (TWAS) using S-PrediXcan. We also conducted phenome-wide association study to understand associations between identified genetic variants and clinical phenotypes. RESULTS: We replicated three 23andMe loci (p ≤ 0.05): herpes zoster and rs7047299-A (p = 2.6 × 10-3) and rs2808290-C (p = 9.6 × 10-3;); otitis media and rs114947103-C (p = 0.04). We also identified 2 novel regions (p ≤ 5 × 10-8): rs113235453-G for otitis media (p = 3.04 × 10-8), and rs10422015-T for candidiasis (p = 3.11 × 10-8). In TWAS, four gene-disease associations were significant: SLC30A9 for otitis media (p = 8.06 × 10-7); LRP3 and WDR88 for candidiasis (p = 3.91 × 10-7 and p = 1.95 × 10-6); and AAMDC for hepatitis B (p = 1.51 × 10-6). CONCLUSION: We conducted GWAS and TWAS for 12 infectious diseases and identified novel genetic contributors to the susceptibility of infectious diseases.


Assuntos
Candidíase , Doenças Transmissíveis , Hepatite B , Herpes Zoster , Otite Média , Bancos de Espécimes Biológicos , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Otite Média/genética , Polimorfismo de Nucleotídeo Único
3.
J Am Chem Soc ; 142(9): 4445-4455, 2020 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-32064871

RESUMO

The lipopolysaccharide biosynthesis pathway is considered an attractive drug target against the rising threat of multi-drug-resistant Gram-negative bacteria. Here, we report two novel small-molecule inhibitors (compounds 1 and 2) of the acyltransferase LpxA, the first enzyme in the lipopolysaccharide biosynthesis pathway. We show genetically that the antibacterial activities of the compounds against efflux-deficient Escherichia coli are mediated by LpxA inhibition. Consistently, the compounds inhibited the LpxA enzymatic reaction in vitro. Intriguingly, using biochemical, biophysical, and structural characterization, we reveal two distinct mechanisms of LpxA inhibition; compound 1 is a substrate-competitive inhibitor targeting apo LpxA, and compound 2 is an uncompetitive inhibitor targeting the LpxA/product complex. Compound 2 exhibited more favorable biological and physicochemical properties than compound 1 and was optimized using structural information to achieve improved antibacterial activity against wild-type E. coli. These results show that LpxA is a promising antibacterial target and imply the advantages of targeting enzyme/product complexes in drug discovery.


Assuntos
Aciltransferases/antagonistas & inibidores , Antibacterianos/farmacologia , Inibidores Enzimáticos/farmacologia , Imidazóis/farmacologia , Pirazóis/farmacologia , Aciltransferases/metabolismo , Antibacterianos/metabolismo , Cristalografia por Raios X , Inibidores Enzimáticos/metabolismo , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Imidazóis/metabolismo , Testes de Sensibilidade Microbiana , Ligação Proteica , Pirazóis/metabolismo
4.
Ann Fam Med ; 14(3): 262-6, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27184997

RESUMO

PURPOSE: Although waist circumference can provide important metabolic risk information, logistic issues inhibit its routine use in outpatient practice settings. We assessed whether self-measured waist circumference is sufficiently accurate to replace professionally measured waist circumference for identifying high-risk patients. METHODS: Medical outpatients and research participants self-measured their waist circumference at the same visit during which a professionally measured waist circumference was obtained. Participants were provided with standardized pictorial instructions on how to measure their waist circumference, and professionals underwent standard training. RESULTS: Self- and professionally measured waist circumference data were collected for 585 women (mean ± SD age = 40 ± 14 years, mean ± SD body mass index = 27.7 ± 6.0 kg/m(2)) and 165 men (mean ± SD age = 41 ± 14 years, mean ± SD body mass index = 29.3 ± 4.6 kg/m(2)). Although self- and professionally measured waist circumference did not differ significantly, we found a clinically important false-negative rate for the self-measurements. Eleven percent of normal-weight and 52% of overweight women had a professionally measured waist circumference putting them in a high-risk category for metabolic syndrome (ie, greater than 88 cm); however, 57% and 18% of these women, respectively, undermeasured their waist circumference as falling below that cutoff. Fifteen percent and 84% of overweight and class I obese men, respectively, had a professionally measured waist circumference putting them in the high-risk category (ie, greater than 102 cm); however, 23% and 16% of these men, respectively, undermeasured their waist circumference as falling below that cutoff. CONCLUSIONS: Despite standardized pictorial instructions for self-measured waist circumference, the false-negative rate of self-measurements approached or exceeded 20% for some groups at high risk for poor health outcomes.


Assuntos
Competência Profissional , Autoexame , Circunferência da Cintura , Adulto , Idoso , Índice de Massa Corporal , Reações Falso-Negativas , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Minnesota , Análise Multivariada , Obesidade/diagnóstico
5.
Endocr Pract ; 22(3): 343-9, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26789339

RESUMO

OBJECTIVE: Lingual thyroid (LT) results from a developmental abnormality due to failure of the thyroid gland to descend to its pretracheal position. Given the low incidence of this disease, standardized management recommendations are lacking. We aimed to describe our institution's experience in LT management and to suggest a practice algorithm. METHODS: We conducted a retrospective review of LT diagnosed at Mayo Clinic, Rochester, Minnesota, between 1976 and 2010. Demographics, clinical presentation, laboratory data, treatment received, and outcomes were collected. RESULTS: We identified 29 patients with LT. Eighty-three percent were female; age at diagnosis ranged from 2 weeks to 68 years. Almost one-third of patients were symptomatic, with the most common symptoms being cough and hoarseness. The diagnosis of LT was incidental in 9 patients (31%). Seventy-two percent of patients developed hypothyroidism. Levothyroxine was the treatment of choice, followed by thyroidectomy. Two asymptomatic euthyroid patients were followed without any intervention. CONCLUSION: Management of patients with LT should be individualized and guided by the patient's symptoms and thyroid hormone status.


Assuntos
Tireoide Lingual/epidemiologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Centros de Atenção Terciária , Atenção Terciária à Saúde/estatística & dados numéricos , Adulto Jovem
6.
Endocr Pract ; 22(4): 466-75, 2016 04.
Artigo em Inglês | MEDLINE | ID: mdl-26789343

RESUMO

OBJECTIVE: We conducted a systematic review and meta-analysis to synthesize the evidence about predictors that may affect biochemical remission and recurrence after transsphenoidal surgery (TSS), radiosurgery (RS), and radiotherapy (RT) in Cushing disease. METHODS: We searched multiple databases through December 2014 including original controlled and uncontrolled studies that enrolled patients with Cushing disease who received TSS (first-line), RS, or RT. We extracted data independently, in duplicates. Outcomes of interest were biochemical remission and recurrence. A meta-analysis was conducted using the random-effects model to estimate event rates with 95% confidence intervals (CIs). RESULTS: First-line TSS was associated with high remission (76% [95% CI, 72 to 79%]) and low recurrence rates (10% [95% CI, 6 to 16%]). Remission after TSS was higher in patients with microadenomas or positive-adrenocorticotropic hormone tumor histology. RT was associated with a high remission rate (RS, 68% [95% CI, 61 to 77%]; RT, 66% [95% CI, 58 to 75%]) but also with a high recurrence rate (RS, 32% [95% CI, 16 to 60%]; RT, 26% [95% CI, 14 to 48%]). Remission after RS was higher at short-term follow-up (≤2 years) and with high-dose radiation, while recurrence was higher in women and with lower-dose radiation. Remission was after RT in adults who received TSS prior to RT, and with lower radiation doses. There was heterogeneity (nonstandardization) in the criteria and cutoff points used to define biochemical remission and recurrence. CONCLUSION: First-line TSS is associated with high remission and low recurrence, while RS and RT are associated with reasonable remission rates but important recurrence rates. The current evidence warrants low confidence due to the noncomparative nature of the studies, high heterogeneity, and imprecision.


Assuntos
Adenoma Hipofisário Secretor de ACT/radioterapia , Adenoma Hipofisário Secretor de ACT/cirurgia , Adenoma/radioterapia , Adenoma/cirurgia , Hipersecreção Hipofisária de ACTH/radioterapia , Hipersecreção Hipofisária de ACTH/cirurgia , Adenoma Hipofisário Secretor de ACT/diagnóstico , Adenoma Hipofisário Secretor de ACT/metabolismo , Adenoma/diagnóstico , Adenoma/metabolismo , Adulto , Biomarcadores/sangue , Feminino , Humanos , Procedimentos Neurocirúrgicos/estatística & dados numéricos , Hipersecreção Hipofisária de ACTH/diagnóstico , Hipersecreção Hipofisária de ACTH/epidemiologia , Prognóstico , Recidiva , Indução de Remissão , Osso Esfenoide/cirurgia , Resultado do Tratamento
7.
Ann Intern Med ; 161(9): 639-49, 2014 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-25364885

RESUMO

BACKGROUND: Multiple treatments for painful diabetic peripheral neuropathy are available. PURPOSE: To evaluate the comparative effectiveness of oral and topical analgesics for diabetic neuropathy. DATA SOURCES: Multiple electronic databases between January 2007 and April 2014, without language restriction. STUDY SELECTION: Parallel or crossover randomized, controlled trials that evaluated pharmacologic treatments for adults with painful diabetic peripheral neuropathy. DATA EXTRACTION: Duplicate extraction of study data and assessment of risk of bias. DATA SYNTHESIS: 65 randomized, controlled trials involving 12 632 patients evaluated 27 pharmacologic interventions. Approximately one half of these studies had high or unclear risk of bias. Nine head-to-head trials showed greater pain reduction associated with serotonin-norepinephrine reuptake inhibitors (SNRIs) than anticonvulsants (standardized mean difference [SMD], -0.34 [95% credible interval {CrI}, -0.63 to -0.05]) and with tricyclic antidepressants (TCAs) than topical capsaicin 0.075%. Network meta-analysis showed that SNRIs (SMD, -1.36 [CrI, -1.77 to -0.95]), topical capsaicin (SMD, -0.91 [CrI, -1.18 to -0.08]), TCAs (SMD, -0.78 [CrI, -1.24 to -0.33]), and anticonvulsants (SMD, -0.67 [CrI, -0.97 to -0.37]) were better than placebo for short-term pain control. Specifically, carbamazepine (SMD, -1.57 [CrI, -2.83 to -0.31]), venlafaxine (SMD, -1.53 [CrI, -2.41 to -0.65]), duloxetine (SMD, -1.33 [CrI, -1.82 to -0.86]), and amitriptyline (SMD, -0.72 [CrI, -1.35 to -0.08]) were more effective than placebo. Adverse effects included somnolence and dizziness with TCAs, SNRIs, and anticonvulsants; xerostomia with TCAs; and peripheral edema and burning sensation with pregabalin and capsaicin. LIMITATION: Confidence in findings was limited because most evidence came from indirect comparisons of trials with short (≤3 months) follow-up and unclear or high risk of bias. CONCLUSION: Several medications may be effective for short-term management of painful diabetic neuropathy, although their comparative effectiveness is unclear. PRIMARY FUNDING SOURCE: Mayo Foundation for Medical Education and Research.


Assuntos
Anticonvulsivantes/uso terapêutico , Antidepressivos Tricíclicos/uso terapêutico , Capsaicina/uso terapêutico , Neuropatias Diabéticas/tratamento farmacológico , Dor/tratamento farmacológico , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Analgésicos Opioides/uso terapêutico , Anticonvulsivantes/efeitos adversos , Antidepressivos Tricíclicos/efeitos adversos , Viés , Capsaicina/efeitos adversos , Neuropatias Diabéticas/complicações , Humanos , Dor/etiologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Inibidores Seletivos de Recaptação de Serotonina/efeitos adversos
8.
Med Care ; 52 Suppl 3: S92-S100, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23969592

RESUMO

BACKGROUND: Poor fidelity to practice guidelines in the care of people with multiple chronic conditions (MCC) may result from patients and clinicians struggling to apply recommendations that do not consider the interplay of MCC, socio-personal context, and patient preferences. OBJECTIVE: The objective of the study was to assess the quality of guideline development and the extent to which guidelines take into account 3 important factors: the impact of MCC, patients' socio-personal contexts, and patients' personal values and preferences. RESEARCH DESIGN: We conducted a systematic search of clinical practice guidelines for patients with type 2 diabetes mellitus published between 2006 and 2012. Ovid Medline In-Process & Other Non-Indexed Citations, Ovid MEDLINE, Ovid EMBASE, Scopus, EBSCO CINAHL, and the National Guideline Clearinghouse were searched. Two reviewers working independently selected studies, extracted data, and evaluated the quality of the guidelines. RESULTS: We found 28 eligible guidelines, which, on average, had major methodological limitations (AGREE II mean score 3.8 of 7, SD=1.6). Patients or methodologists were not included in the guideline development process in 20 (71%) and 24 (86%) guidelines, respectively. There was a complete absence of incorporating the impact of MCC, socio-personal context, and patient preferences in 8 (29%), 11 (39%), and 16 (57%) of the 28 guidelines, respectively. When mentioned, MCC were considered biologically, but not as contributors of complexity or patient work or as motivation to focus on patient-centered outcomes. CONCLUSIONS: Extant clinical practice guidelines for one chronic disease sometimes consider the context of the patient with that disease, but only do so narrowly. Guideline panels must remove their contextual blinders if they want to practically guide the care of patients with MCC.


Assuntos
Complicações do Diabetes/prevenção & controle , Diabetes Mellitus Tipo 2/terapia , Promoção da Saúde/estatística & dados numéricos , Assistência Centrada no Paciente/estatística & dados numéricos , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Complicações do Diabetes/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Gerenciamento Clínico , Medicina Baseada em Evidências , Fidelidade a Diretrizes , Educação em Saúde/estatística & dados numéricos , Humanos , Estados Unidos/epidemiologia
9.
Clin Obes ; 14(1): e12616, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37532290

RESUMO

Obesity is known to be associated with numerous ocular manifestations, including but not limited to, diabetic retinopathy (DR), age-related macular degeneration (AMD), cataracts, glaucoma, and dry eye disease. This review aims to provide an overview of the ophthalmological findings in obesity. A literature search was conducted using PubMed and Cochrane databases for studies describing randomized clinical trials, meta-analyses, systematic reviews, and observational studies published from 1 January 2017 to 1 April 2023. The search terms used included relevant keywords such as 'obesity', 'body mass index', 'waist-to-hip ratio', 'bariatric', 'ophthalmology', 'eye disease', 'myopia', 'retinopathy', 'glaucoma', and 'cataract'. This literature search was performed on 1 April 2023. Obesity is associated with increased risk of developing DR, a sight-threatening complication of diabetes mellitus. Similarly, obesity has been shown to increase risk of AMD, cataracts, glaucoma, and ocular surface disease. Multiple mechanisms linking obesity to ophthalmic disease have been proposed. Adipose tissue produces various inflammatory cytokines that can affect ocular tissues, leading to disease progression. Additionally, obesity is associated with systemic metabolic changes that can influence ocular health. Bariatric surgery has been shown to be protective against development of ophthalmic disease. Obesity is a significant risk factor for several ophthalmological diseases. Healthcare providers should encourage weight loss in patients with overweight or obesity to prevent or delay the onset of ocular complications. Further research is needed to better understand the underlying mechanisms of this association, and to identify effective strategies for preventing or managing ophthalmic disease in patients with obesity.


Assuntos
Catarata , Retinopatia Diabética , Glaucoma , Degeneração Macular , Humanos , Catarata/complicações , Glaucoma/complicações , Retinopatia Diabética/complicações , Degeneração Macular/complicações , Obesidade/complicações
10.
ACS Chem Biol ; 19(1): 58-68, 2024 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-38192078

RESUMO

Targeted protein degradation has arisen as a powerful therapeutic modality for eliminating proteins. Thus far, most heterobifunctional proteolysis targeting chimeras (PROTACs) have utilized recruiters against substrate receptors of Cullin RING E3 ubiquitin ligases, such as cereblon and VHL. However, previous studies have surprisingly uncovered molecular glue degraders that exploit a CUL4 adaptor protein DDB1 to degrade neosubstrate proteins. Here, we sought to investigate whether DDB1 recruiters can be discovered that can be exploited for PROTAC applications. We utilized activity-based protein profiling and cysteine chemoproteomic screening to identify a covalent recruiter that targets C173 on DDB1 and exploited this recruiter to develop PROTACs against BRD4 and androgen receptor (AR). We demonstrated that the BRD4 PROTAC results in selective degradation of the short BRD4 isoform over the long isoform in a proteasome, NEDDylation, and DDB1-dependent manner. We also demonstrated degradation of AR with the AR PROTAC in prostate cancer cells. Our study demonstrated that covalent chemoproteomic approaches can be used to discover recruiters against Cullin RING adapter proteins and that these recruiters can be used for PROTAC applications to degrade neo-substrates.


Assuntos
Proteínas Culina , Fatores de Transcrição , Proteólise , Proteínas Culina/metabolismo , Fatores de Transcrição/metabolismo , Proteínas Nucleares/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Isoformas de Proteínas/metabolismo
11.
Artigo em Inglês | MEDLINE | ID: mdl-23295477

RESUMO

Acinetobacter baumannii is a Gram-negative bacterium that is resistant to many currently available antibiotics. The protein LpxD is a component of the biosynthetic pathway for lipopolysaccharides in the outer membrane of this bacterium and is a potential target for new antibacterial agents. This paper describes the structure determination of apo forms of LpxD in space groups P2(1) and P4(3)22. These crystals contained six and three copies of the protein molecule in the asymmetric unit and diffracted to 2.8 and 2.7 Šresolution, respectively. A comparison of the multiple protein copies in the asymmetric units of these crystals reveals a common protein conformation and a conformation in which the relative orientation between the two major domains in the protein is altered.


Assuntos
Acinetobacter baumannii/química , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Cristalografia por Raios X , Modelos Moleculares , Conformação Proteica , Estrutura Terciária de Proteína
12.
bioRxiv ; 2023 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-37614621

RESUMO

Targeted protein degradation has arisen as a powerful therapeutic modality for eliminating proteins. Thus far, most heterobifunctional Proteolysis Targeting Chimeras (PROTACs) have utilized recruiters against substrate receptors of Cullin RING E3 ubiquitin ligases, such as cereblon and VHL. However, previous studies have surprisingly uncovered molecular glue degraders that exploit a CUL4A adaptor protein DDB1 to degrade neosubstrate proteins. Here, we sought to investigate whether DDB1 recruiters can be discovered that can be exploited for PROTAC applications. We utilized activity-based protein profiling and cysteine chemoproteomic screening to identify a covalent recruiter that targets C173 on DDB1 and exploited this recruiter to develop PROTACs against BRD4 and androgen receptor (AR). We demonstrated that the BRD4 PROTAC results in selective degradation of the short BRD4 isoform over the long isoform in a proteasome, NEDDylation, and DDB1-dependent manner. We also demonstrated degradation of AR with the AR PROTAC in prostate cancer cells. Our study demonstrated that covalent chemoproteomic approaches can be used to discover recruiters against Cullin RING adapter proteins and that these recruiters can be used for PROTAC applications to degrade neo-substrates.

13.
Sci Rep ; 13(1): 22088, 2023 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-38086859

RESUMO

The design of cereblon-binding molecular glues (MGs) that selectively recruit a desired protein while excluding teratogenic SALL4 is an area of significant interest when designing therapeutic agents. Previous studies show that SALL4 is degraded in the presence of IKZF1 degraders pomalidomide, and to a lesser extent by CC-220. To expand our understanding of the molecular basis for the interaction of SALL4 with cereblon, we performed biophysical and structural studies demonstrating that SALL4 zinc finger domains one and two (ZF1-2) interact with cereblon (CRBN) in a unique manner. ZF1 interacts with the N-terminal domain of cereblon and ZF2 binds as expected in the C-terminal IMiD-binding domain. Both ZF1 and ZF2 contribute to the potency of the interaction of ZF1-2 with CRBN:MG complexes and the affinities of SALL4 ZF1-2 for the cereblon:CC-220 complex are less potent than for the corresponding pomalidomide complex. Structural analysis provides a rationale for understanding the reduced affinity of SALL4 for cereblon in the presence of CC-220, which engages both ZF1 and ZF2. These studies further our understanding of the molecular glue-mediated interactions of zinc finger-based proteins with cereblon and may provide structural tools for the prospective design of compounds with reduced binding and degradation of SALL4.


Assuntos
Talidomida , Dedos de Zinco , Talidomida/farmacologia , Talidomida/química , Teratogênicos , Ubiquitina-Proteína Ligases/metabolismo
14.
Int J Radiat Oncol Biol Phys ; 116(2): 448-458, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36549348

RESUMO

PURPOSE: Latin America faces a shortage in radiation therapy (RT) units and qualified personnel for timely and high-quality treatment of patients with cancer. Investing in equitable and inclusive access to RT over the next decade would prevent thousands of deaths. Measuring the investment gap and payoff is necessary for stakeholder discussions and capacity planning efforts. METHODS AND MATERIALS: Data were collected from the International Atomic Energy Agency's Directory of Radiotherapy Centers, industry stakeholders, and individual surveys sent to national scientific societies. Nationwide data on available devices and personnel were compiled. The 10 most common cancers in 2020 with RT indication and their respective incidence rates were considered for gap calculations. The gross 2-year financial return on investment was calculated based on an average monthly salary across Latin America. A 10-year cost projection was calculated according to the estimated population dynamics for the period until 2030. RESULTS: Eleven countries were included in the study, accounting for 557,213,447 people in 2020 and 561 RT facilities. Approximately 1,065,684 new cancer cases were diagnosed, and a mean density of 768,469 (standard deviation ±392,778) people per available unit was found. By projecting the currently available treatment fractions to determine those required in 2030, it was found that 62.3% and 130.8% increases in external beam RT and brachytherapy units are needed from the baseline, respectively. An overall regional investment of approximately United States (US) $349,650,480 in 2020 would have covered the existing demand. An investment of US $872,889,949 will be necessary by 2030, with the expectation of a 2-year posttreatment gross return on investment of more than US $2.1 billion from patients treated in 2030 only. CONCLUSIONS: Investment in RT services is lagging in Latin America in terms of the population's needs. An accelerated outlay could save additional lives during the next decade, create a self-sustaining system, and reduce region-wide inequities in cancer care access. Cash flow analyses are warranted to tailor precise national-level intervention strategies.


Assuntos
Braquiterapia , Neoplasias , Radioterapia (Especialidade) , Humanos , América Latina/epidemiologia , Neoplasias/radioterapia , Investimentos em Saúde
15.
Int J Pharm ; 644: 123331, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37597595

RESUMO

Controlled-release formulations for pulmonary delivery are highly desirable for treating chronic diseases such as COPD. However, a limited number of polymers are currently approved for inhalation. The study presents a promising strategy using gelatin as a matrix for inhalable dry powders, allowing the controlled release of ionic drugs. Ionized cromoglicate sodium (CS) and ipratropium bromide (IBr) interacted in solution with charged gelatin before spray drying (SD). Calcium carbonate was used as a crosslinker. The microspheres showed remarkable aerosol performance after optimizing the SD parameters and did not cause cytotoxicity in A549 cells. The microspheres were highly dispersible with âˆ¼ 50-60% of respirable fraction and fine particle fraction 55-70%. Uncrosslinked microspheres increased their size from four to ten times by swelling after 5 min showing potential as a strategy to avoid macrophage clearance and prolong the therapeutic effect of the drug. Crosslinkers prevented particle swelling. Ionic interaction generated a moderate reduction of the drug release. Overall, this study provides a novel approach for developing DPI formulations for treating chronic respiratory diseases using a biopolymer approved by the FDA, potentially enhancing drug activity through controlled release and avoiding macrophage clearance.


Assuntos
Cromolina Sódica , Gelatina , Preparações de Ação Retardada , Ipratrópio , Microesferas
16.
Cell Chem Biol ; 30(3): 235-247.e12, 2023 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-36863346

RESUMO

Malignant tumors can evade destruction by the immune system by attracting immune-suppressive regulatory T cells (Treg) cells. The IKZF2 (Helios) transcription factor plays a crucial role in maintaining function and stability of Treg cells, and IKZF2 deficiency reduces tumor growth in mice. Here we report the discovery of NVP-DKY709, a selective molecular glue degrader of IKZF2 that spares IKZF1/3. We describe the recruitment-guided medicinal chemistry campaign leading to NVP-DKY709 that redirected the degradation selectivity of cereblon (CRBN) binders from IKZF1 toward IKZF2. Selectivity of NVP-DKY709 for IKZF2 was rationalized by analyzing the DDB1:CRBN:NVP-DKY709:IKZF2(ZF2 or ZF2-3) ternary complex X-ray structures. Exposure to NVP-DKY709 reduced the suppressive activity of human Treg cells and rescued cytokine production in exhausted T-effector cells. In vivo, treatment with NVP-DKY709 delayed tumor growth in mice with a humanized immune system and enhanced immunization responses in cynomolgus monkeys. NVP-DKY709 is being investigated in the clinic as an immune-enhancing agent for cancer immunotherapy.


Assuntos
Neoplasias , Fatores de Transcrição , Animais , Humanos , Camundongos , Fator de Transcrição Ikaros , Imunoterapia , Neoplasias/terapia , Neoplasias/metabolismo , Linfócitos T Reguladores/metabolismo , Fatores de Transcrição/metabolismo
17.
Acta Crystallogr Sect F Struct Biol Cryst Commun ; 68(Pt 12): 1477-81, 2012 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-23192027

RESUMO

Acinetobacter baumannii is a Gram-negative pathogenic bacterium which is resistant to most currently available antibiotics and that poses a significant health threat to hospital patients. LpxA is a key enzyme in the biosynthetic pathway of the lipopolysaccharides that are components of the bacterial outer membrane. It is a potential target for antibacterial agents that might be used to fight A. baumannii infections. This paper describes the structure determination of the apo form of LpxA in space groups P2(1)2(1)2(1) and P6(3). These crystal forms contained three and one protein molecules in the asymmetric unit and diffracted to 1.8 and 1.4 Šresolution, respectively. A comparison of the conformations of the independent protein monomers within and between the two crystal asymmetric units revealed very little structural variation across this set of structures. In the P6(3) crystal form the enzymatic site is exposed and is available for the introduction of small molecules of the type used in fragment-based drug discovery and structure-based lead optimization.


Assuntos
Acinetobacter baumannii/enzimologia , Aciltransferases/química , Proteínas da Membrana Bacteriana Externa/química , Proteínas de Bactérias/química , Acinetobacter baumannii/metabolismo , Aciltransferases/metabolismo , Proteínas da Membrana Bacteriana Externa/metabolismo , Proteínas de Bactérias/metabolismo , Cristalografia por Raios X , Modelos Moleculares , Conformação Proteica
18.
Diabetes ; 71(3): 381-393, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34857544

RESUMO

The role of adipose tissue (AT) inflammation in AT function in humans is unclear. We tested whether AT macrophage (ATM) content, cytokine gene expression, and senescent cell burden (markers of AT inflammation) predict AT insulin resistance measured as the insulin concentration that suppresses lipolysis by 50% (IC50). We studied 86 volunteers with normal weight or obesity at baseline and a subgroup of 25 volunteers with obesity before and after weight loss. There was a strong positive relationship between IC50 and abdominal subcutaneous and femoral fat cell size (FCS). The positive, univariate relationships between IC50 and abdominal AT inflammatory markers CD68, CD14, CD206 ATM/100 adipocytes, senescent cells, IL-6, and TNF-α mRNA were not significant after adjustment for FCS. A 10% weight loss significantly reduced IC50; however, there was no reduction in adipose ATM content, senescent cells, or cytokine gene expression. Our study suggests that commonly used markers of AT inflammation are not causally linked to AT insulin resistance, whereas FCS is a strong predictor of AT insulin resistance with respect to lipolysis.


Assuntos
Tecido Adiposo/fisiopatologia , Inflamação/fisiopatologia , Resistência à Insulina/fisiologia , Obesidade/fisiopatologia , Gordura Abdominal/patologia , Gordura Abdominal/fisiopatologia , Adipócitos/patologia , Tecido Adiposo/patologia , Adulto , Glicemia/metabolismo , Tamanho Celular , Senescência Celular , Citocinas/análise , Citocinas/genética , Feminino , Expressão Gênica , Humanos , Inflamação/patologia , Insulina/sangue , Macrófagos/patologia , Masculino , Pessoa de Meia-Idade , Obesidade/patologia , Redução de Peso/fisiologia
19.
Artigo em Inglês | MEDLINE | ID: mdl-21795786

RESUMO

LpxD is a bacterial protein that is part of the biosynthesis pathway of lipid A and is responsible for transferring 3-hydroxymyristic acid from the R-3-hydroxymyristoyl-acyl carrier protein to the 2-OH group of UDP-3-O-(3-hydroxymyristoyl) glucosamine. The crystal structure of LpxD from Pseudomonas aeruginosa has been determined at high resolution (1.3 Å). The crystal belonged to space group H3, with unit-cell parameters a=b=106.19, c=93.38 Å, and contained one molecule in the asymmetric unit. The structure was solved by molecular replacement using the known structure of LpxD from Escherichia coli (PDB entry 3eh0) as a search model and was refined to Rwork=16.4% (Rfree=18.5%) using 91,655 reflections. The final protein model includes 355 amino-acid residues (including 16 amino acids from a 20 amino-acid N-terminal His tag), one chloride ion and two ethylene glycol molecules.


Assuntos
Aciltransferases/química , Pseudomonas aeruginosa/enzimologia , Cristalografia por Raios X , Ligantes , Modelos Moleculares , Estrutura Quaternária de Proteína , Homologia Estrutural de Proteína
20.
Obesity (Silver Spring) ; 29(8): 1320-1327, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34114359

RESUMO

OBJECTIVE: Adipose tissue (AT) senescence is associated with AT dysfunction in rodents, but little is known about human AT senescence. The study goal was to define the distribution of senescent cells in two subcutaneous depots and understand relationships with adiposity and inflammation. METHODS: Sixty-three volunteers (48 females) underwent abdominal and femoral subcutaneous fat biopsies. Fat cell size, senescent cells using senescence-associated ß-galactosidase staining per 100 nucleated cells (percentage), and mRNA expression of four cytokines were measured. RESULTS: There was a larger proportion of senescent cells in femoral than abdominal subcutaneous AT (mean difference 1.6% [95% CI: 0.98%-2.3%], p < 0.001), and the percentage of femoral AT senescent cells was greater in women than men (median 3.9% vs. 2.1%, p < 0.01). There was a positive correlation between senescence and fat cell size in abdominal (rs  = 0.44, p < 0.001) and femoral (rs  = 0.35, p = 0.007) AT depots. Abdominal AT tumor necrosis factor alpha (rs  = 0.49, p < 0.01) and interleukin-1ß (rs  = 0.44, p = 0.01) expression was positively correlated with abdominal, but not femoral, AT senescence. CONCLUSIONS: In human subcutaneous AT, there are more senescent cells in femoral than abdominal depots; abdominal AT senescent cells are more associated with inflammatory signals than femoral AT senescent cells.


Assuntos
Tecido Adiposo , Obesidade , Tecido Adiposo/metabolismo , Adiposidade , Senescência Celular , Estudos Transversais , Feminino , Humanos , Masculino , Obesidade/metabolismo , Gordura Subcutânea Abdominal
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