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1.
Nat Chem Biol ; 19(10): 1205-1214, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37248411

RESUMO

The microbiota generates diverse metabolites to modulate host physiology and disease, but their protein targets and mechanisms of action have not been fully elucidated. To address this challenge, we explored microbiota-derived indole metabolites and developed photoaffinity chemical reporters for proteomic studies. We identified many potential indole metabolite-interacting proteins, including metabolic enzymes, transporters, immune sensors and G protein-coupled receptors. Notably, we discovered that aromatic monoamines can bind the orphan receptor GPRC5A and stimulate ß-arrestin recruitment. Metabolomic and functional profiling also revealed specific amino acid decarboxylase-expressing microbiota species that produce aromatic monoamine agonists for GPRC5A-ß-arrestin recruitment. Our analysis of synthetic aromatic monoamine derivatives identified 7-fluorotryptamine as a more potent agonist of GPRC5A. These results highlight the utility of chemoproteomics to identify microbiota metabolite-interacting proteins and the development of small-molecule agonists for orphan receptors.


Assuntos
Microbiota , Proteômica , Receptores Acoplados a Proteínas G/metabolismo , beta-Arrestinas/metabolismo , Indóis
2.
EMBO Rep ; 24(1): e55640, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36397732

RESUMO

Understanding the interplay between phenotypic and genetic adaptation is a focus of evolutionary biology. In bacteria, the oxidative stress response prevents mutagenesis by reactive oxygen species (ROS). We hypothesise that the stress response dynamics can therefore affect the timing of the mutation supply that fuels genetic adaptation to oxidative stress. We uncover that sudden hydrogen peroxide stress causes a burst of mutations. By developing single-molecule and single-cell microscopy methods, we determine how these mutation dynamics arise from phenotypic adaptation mechanisms. H2 O2 signalling by the transcription factor OxyR rapidly induces ROS-scavenging enzymes. However, an adaptation delay leaves cells vulnerable to the mutagenic and toxic effects of hydroxyl radicals generated by the Fenton reaction. Resulting DNA damage is counteracted by a spike in DNA repair activities during the adaptation delay. Absence of a mutation burst in cells with prior stress exposure or constitutive OxyR activation shows that the timing of phenotypic adaptation directly controls stress-induced mutagenesis. Similar observations for alkylation stress show that mutation bursts are a general phenomenon associated with adaptation delays.


Assuntos
Peróxido de Hidrogênio , Estresse Oxidativo , Espécies Reativas de Oxigênio , Mutação , Mutagênese , Peróxido de Hidrogênio/toxicidade , Bactérias
3.
Proc Natl Acad Sci U S A ; 119(32): e2200879119, 2022 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-35925889

RESUMO

The value of anti-CTLA-4 antibodies in cancer therapy is well established. However, the broad application of currently available anti-CTLA-4 therapeutic antibodies is hampered by their narrow therapeutic index. It is therefore challenging and attractive to develop the next generation of anti-CTLA-4 therapeutics with improved safety and efficacy. To this end, we generated fully human heavy chain-only antibodies (HCAbs) against CTLA-4. The hIgG1 Fc domain of the top candidate, HCAb 4003-1, was further engineered to enhance its regulatory T (Treg) cell depletion effect and to decrease its half-life, resulting in HCAb 4003-2. We tested these HCAbs in in vitro and in vivo experiments in comparison with ipilimumab and other anti-CTLA4 antibodies. The results show that human HCAb 4003-2 binds human CTLA-4 with high affinity and potently blocks the binding of B7-1 (CD80) and B7-2 (CD86) to CTLA-4. The results also show efficient tumor penetration. HCAb 4003-2 exhibits enhanced antibody-dependent cellular cytotoxicity function, lower serum exposure, and more potent anti-tumor activity than ipilimumab in murine tumor models, which is partly driven by a substantial depletion of intratumoral Tregs. Importantly, the enhanced efficacy combined with the shorter serum half-life and less systemic drug exposure in vivo potentially provides an improved therapeutic window in cynomolgus monkeys and preliminary clinical applications. With its augmented efficacy via Treg depletion and improved safety profile, HCAb 4003-2 is a promising candidate for the development of next generation anti-CTLA-4 therapy.


Assuntos
Cadeias Pesadas de Imunoglobulinas , Imunoterapia , Neoplasias , Linfócitos T Reguladores , Animais , Citotoxicidade Celular Dependente de Anticorpos , Antígeno CTLA-4/imunologia , Humanos , Cadeias Pesadas de Imunoglobulinas/farmacologia , Ipilimumab/farmacologia , Camundongos , Neoplasias/patologia , Neoplasias/terapia
4.
Prostate ; 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38946139

RESUMO

BACKGROUND: The link between the prostate microbiome and prostate cancer remains unclear. Few studies have analyzed the microbiota of prostate tissue, and these have been limited by potential contamination by transrectal biopsy. Transperineal prostate biopsy offers an alternative and avoids fecal cross-contamination. We aim to characterize the prostate microbiome using transperineal biopsy. METHODS: Patients with clinical suspicion for prostate cancer who were to undergo transperineal prostate biopsy with magnetic resonance imaging (MRI) fusion guidance were prospectively enrolled from 2022 to 2023. Patients were excluded if they had Prostate Imaging Reporting and Data System lesions with scores ≤ 3, a history of prostate biopsy within 1 year, a history of prostate cancer, or antibiotic use within 30 days of biopsy. Tissue was collected from the MRI target lesions and nonneoplastic transitional zone. Bacteria were identified using 16S ribosomal RNA gene sequencing. RESULTS: Across the 42 patients, 76% were found to have prostate cancer. Beta diversity indices differed significantly between the perineum, voided urine, and prostate tissue. There were no beta diversity differences between cancerous or benign tissue, or between pre- and postbiopsy urines. There appear to be unique genera more abundant in cancerous versus benign tissue. There were no differences in alpha diversity indices relative to clinical findings including cancer status, grade, and risk group. CONCLUSIONS: We demonstrate a rigorous method to better characterize the prostate microbiome using transperineal biopsy and to limit contamination. These findings provide a framework for future large-scale studies of the microbiome of prostate cancer.

5.
Am J Hum Genet ; 108(1): 163-175, 2021 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-33357406

RESUMO

The lack of functional evidence for the majority of missense variants limits their clinical interpretability and poses a key barrier to the broad utility of carrier screening. In Lynch syndrome (LS), one of the most highly prevalent cancer syndromes, nearly 90% of clinically observed missense variants are deemed "variants of uncertain significance" (VUS). To systematically resolve their functional status, we performed a massively parallel screen in human cells to identify loss-of-function missense variants in the key DNA mismatch repair factor MSH2. The resulting functional effect map is substantially complete, covering 94% of the 17,746 possible variants, and is highly concordant (96%) with existing functional data and expert clinicians' interpretations. The large majority (89%) of missense variants were functionally neutral, perhaps unexpectedly in light of its evolutionary conservation. These data provide ready-to-use functional evidence to resolve the ∼1,300 extant missense VUSs in MSH2 and may facilitate the prospective classification of newly discovered variants in the clinic.


Assuntos
Predisposição Genética para Doença/genética , Proteína 2 Homóloga a MutS/genética , Mutação de Sentido Incorreto/genética , Neoplasias Colorretais Hereditárias sem Polipose/genética , Reparo de Erro de Pareamento de DNA/genética , Células HEK293 , Humanos
6.
J Acoust Soc Am ; 153(1): 40, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36732239

RESUMO

Nanofiber-porous systems comprising a porous substrate overlaid with nanofiber weave offer the potential for higher acoustic absorption than the substrate alone with negligible increase in thickness. The characterization of nanofibers from acoustic measurements is investigated in this work, and a regression model for predicting their acoustic properties from a single physical parameter is proposed to enable the design of nanofiber-porous systems directly from fabrication parameters. Characterization as a resistive screen via Johnson-Champoux-Allard and lumped element models for transfer matrix computations of absorption coefficient for nanofiber-porous systems exhibited good agreement with the measured spectra. The lumped element model was chosen as it was defined by fewer parameters and did not require nanofiber layer thickness measurements, eliminating the associated uncertainty. A regression model for lumped element parameters vs areal density established a design tool based on a single, easily measured physical property for optimized absorption at target frequencies without prior acoustic characterization of the nanofiber layer, enabling the analysis of complex acoustic networks incorporating nanofiber-porous systems. Practical considerations of applying adhesives at the nanofiber-porous interface were studied to evaluate possible enhancement of acoustic performance. For comparison with prior work by others, flow resistances from physical measurement and acoustic characterization were compared.

8.
IEEE Sens J ; 23(10): 10998-11006, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37547101

RESUMO

Abnormal gait is a significant non-cognitive biomarker for Alzheimer's disease (AD) and AD-related dementia (ADRD). Micro-Doppler radar, a non-wearable technology, can capture human gait movements for potential early ADRD risk assessment. In this research, we propose to design STRIDE integrating micro-Doppler radar sensors with advanced artificial intelligence (AI) technologies. STRIDE embeds a new deep learning (DL) classification framework. As a proof of concept, we develop a "digital-twin" of STRIDE, consisting of a human walking simulation model and a micro-Doppler radar simulation model, to generate a gait signature dataset. Taking established human walking parameters, the walking model simulates individuals with ADRD under various conditions. The radar model based on electromagnetic scattering and the Doppler frequency shift model is employed to generate micro-Doppler signatures from different moving body parts (e.g., foot, limb, joint, torso, shoulder, etc.). A band-dependent DL framework is developed to predict ADRD risks. The experimental results demonstrate the effectiveness and feasibility of STRIDE for evaluating ADRD risk.

9.
Qatar Med J ; 2023(4): 36, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38187991

RESUMO

The opioid crisis has become a significant public health concern in recent years. Although respiratory depression and overdose are the most reported side effects of fentanyl, there have been rare cases of cerebellar leukoencephalopathy (CLE) following fentanyl intoxication. A 29-year-old man with a history of opioid use disorder and intravenous drug use presented to the emergency room with significant ataxia and dysarthria following fentanyl intoxication. According to the patient, the symptoms began four days prior after "chasing the dragon" with "pure fentanyl", and he reported experiencing nausea and dizziness, particularly during ambulation. Neurological examination revealed a positive Romberg test, ataxia, and delayed speech. Brain magnetic resonance imaging (MRI) indicated there was toxic degeneration of the cerebellar white matter that extended into the posterior limbs of the internal capsule. Urine drug screening was positive for opioids, making fentanyl-induced cerebellar leukoencephalopathy the most likely diagnosis in this case. This case of opioid-induced CLE underscores the critical significance of early recognition, which is vital for enhancing a patient's recovery and averting the development of severe neurological complications.

10.
Anal Chem ; 94(34): 11723-11727, 2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-35981215

RESUMO

Adeno-associated viral (AAV) vectors have emerged as gene therapy and vaccine delivery systems. Differential scanning fluorimetry or differential scanning calorimetry is commonly used to measure the thermal stability of AAVs, but these global methods are unable to distinguish the stabilities of different AAV subpopulations in the same sample. To address this challenge, we combined charge detection-mass spectrometry (CD-MS) with a variable temperature (VT) electrospray source that controls the temperature of the solution prior to electrospray. Using VT-CD-MS, we measured the thermal stabilities of empty and filled capsids. We found that filled AAVs ejected their cargo first and formed intermediate empty capsids before completely dissociating. Finally, we observed that pH stress caused a major decrease in thermal stability. This new approach better characterizes the thermal dissociation of AAVs, providing the simultaneous measurement of the stabilities and dissociation pathways of different subpopulations.


Assuntos
Capsídeo , Dependovirus , Capsídeo/química , Proteínas do Capsídeo/química , Dependovirus/química , Espectrometria de Massas , Temperatura
11.
J Urol ; 207(1): 77-85, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34445890

RESUMO

PURPOSE: The ideal number of neoadjuvant chemotherapy (NAC) cycles for muscle-invasive bladder cancer is uncertain with 3 to 4 representing the standard of care (SOC). We compared ypT0 rates and survival between patients receiving 4 versus 3 cycles of NAC with evaluation of chemotherapy-related toxicity for correlation with tumor chemosensitivity and pathological response. MATERIALS AND METHODS: Patients receiving NAC followed by radical cystectomy for cT2-4N0M0 urothelial carcinoma from 2 institutions were included. Primary study groups included 4 cisplatin-based NAC cycles, 3 cisplatin-based NAC cycles, and nonSOC NAC (1-2 cycles or noncisplatin-based) to compare ypT0/≤ypT1 rates and survival. A cohort of patients not receiving NAC was included for pathological reference. RESULTS: Of 693 total patients, 318 (45.9%) received NAC. ypT0 and ≤ypT1 rates were 42/157 (26.8%) and 86/157 (54.8%) for 4 cycles, 38/114 (33.3%) and 71/114 (62.3%) for 3 cycles, and 6/47 (12.8%) and 13/47 (27.7%) for nonSOC (p=0.03 and p <0.01, respectively). Pathological response appeared higher among patients receiving 3 cycles due to toxicity (ypT0: 29/77 [37.7%]; ≤ypT1: 51/77 [66.2%]) but did not reach statistical significance. Toxicities leading to treatment modifications were thrombocytopenia (32.1%), neutropenia (27.2%), renal insufficiency (22.2%), and constitutional symptoms (18.5%). NonSOC patients had lower Kaplan-Meier survival (cT2-cT4N0M0: log-rank p=0.07; cT2N0M0: log-rank p=0.02). There were no statistically significant differences in survival between 4 and 3 cycles (HR 1.00 [95% CI 0.57-1.74], p=0.99). CONCLUSIONS: Patients completing 3 cycles of cisplatin-based NAC have similar pathologic response and short-term survival compared to 4 cycles. Further evaluation of patients experiencing toxicity as a potential marker of tumor chemosensitivity is needed.


Assuntos
Antineoplásicos/administração & dosagem , Cisplatino/administração & dosagem , Terapia Neoadjuvante/estatística & dados numéricos , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/mortalidade , Idoso , Cistectomia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/cirurgia
12.
Anal Chem ; 93(44): 14722-14729, 2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34705424

RESUMO

Native mass spectrometry (MS) has become a versatile tool for characterizing high-mass complexes and measuring biomolecular interactions. Native MS usually requires the resolution of different charge states produced by electrospray ionization to measure the mass, which is difficult for highly heterogeneous samples that have overlapping and unresolvable charge states. Charge detection-mass spectrometry (CD-MS) seeks to address this challenge by simultaneously measuring the charge and m/z for isolated ions. However, CD-MS often shows uncertainty in the charge measurement that limits the resolution. To overcome this charge state uncertainty, we developed UniDecCD (UCD) software for computational deconvolution of CD-MS data, which significantly improves the resolution of CD-MS data. Here, we describe the UCD algorithm and demonstrate its ability to improve the CD-MS resolution of proteins, megadalton viral capsids, and heterogeneous nanodiscs made from natural lipid extracts. UCD provides a user-friendly interface that will increase the accessibility of CD-MS technology and provide a valuable new computational tool for CD-MS data analysis.


Assuntos
Proteínas , Espectrometria de Massas por Ionização por Electrospray , Algoritmos , Íons , Software
13.
Appl Environ Microbiol ; 87(18): e0084421, 2021 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-34232061

RESUMO

Enterococcus faecium is a ubiquitous Gram-positive bacterium that has been recovered from the environment, food, and microbiota of mammals. Commensal strains of E. faecium can confer beneficial effects on host physiology and immunity, but antibiotic usage has afforded antibiotic-resistant and pathogenic isolates from livestock and humans. However, the dissection of E. faecium functions and mechanisms has been restricted by inefficient gene-editing methods. To address these limitations, here, we report that the expression of E. faecium RecT recombinase significantly improves the efficiency of recombineering technologies in both commensal and antibiotic-resistant strains of E. faecium and other Enterococcus species such as E. durans and E. hirae. Notably, the expression of RecT in combination with clustered regularly interspaced short palindromic repeat (CRISPR)-Cas9 and guide RNAs (gRNAs) enabled highly efficient scarless single-stranded DNA recombineering to generate specific gene-editing mutants in E. faecium. Moreover, we demonstrate that E. faecium RecT expression facilitated chromosomal insertions of double-stranded DNA templates encoding antibiotic-selectable markers to generate gene deletion mutants. As a further proof of principle, we use CRISPR-Cas9-mediated recombineering to knock out both sortase A genes in E. faecium for downstream functional characterization. The general RecT-mediated recombineering methods described here should significantly enhance genetic studies of E. faecium and other closely related species for functional and mechanistic studies. IMPORTANCE Enterococcus faecium is widely recognized as an emerging public health threat with the rise of drug resistance and nosocomial infections. Nevertheless, commensal Enterococcus strains possess beneficial health functions in mammals to upregulate host immunity and prevent microbial infections. This functional dichotomy of Enterococcus species and strains highlights the need for in-depth studies to discover and characterize the genetic components underlying its diverse activities. However, current genetic engineering methods in E. faecium still require passive homologous recombination from plasmid DNA. This involves the successful cloning of multiple homologous fragments into a plasmid, introducing the plasmid into E. faecium, and screening for double-crossover events that can collectively take up to multiple weeks to perform. To alleviate these challenges, we show that RecT recombinase enables the rapid and efficient integration of mutagenic DNA templates to generate substitutions, deletions, and insertions in the genomic DNA of E. faecium. These improved recombineering methods should facilitate functional and mechanistic studies of Enterococcus.


Assuntos
Proteínas de Bactérias/genética , Enterococcus faecium/genética , Edição de Genes , Recombinases/genética , Proteína 9 Associada à CRISPR/genética , Sistemas CRISPR-Cas , Streptococcus pyogenes/genética
14.
J Environ Manage ; 295: 113095, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34157541

RESUMO

Effective solutions for efficient carbon dioxide (CO2) capture in air at room temperature are in high demand due to the major impacts CO2 has on global climatic changes. Solid adsorbents materials for CO2 capture received great attention over the past years, among them, magnesium-based sorbents have been identified as a promising solution for CO2 capture at intermediate temperatures. This study reports for the first time (1) the synthesis of monoclinic magnesium malate tetrahydrate by combining electrospinning and aging processes, and (2) its room temperature CO2 adsorption and mineralization in air. Commercial magnesium hydroxide (Mg(OH)2) powder was used as raw material in the synthesis of magnesium carbonate hydrates (MCH), by three processes; (1) direct calcination, (2) electrospinning and calcination, and (3) electrospinning, calcination, and aging (at room temperature and in air to incubate CO2 mineralization). The synthesized powder samples were characterized thoroughly using XRD, SEM, EDS, and TGA analyses. Effects of calcination temperature/aging time on CO2 adsorption (at room temperature), crystallization, and mineralization of MCH were studied. Interestingly, the results showed that the 6-month aged samples (via the third synthesis process above), recorded a CO2 adsorption capacity of 15.5 wt% within 90 min at 30 °C. Subsequently, three novel mechanisms of thermal decomposition CO2 adsorption/mineralization were proposed, and a theoretical upper limit of carbon saving potentials was estimated, i.e., 8 mol CO2 per 1 mol MgO. This work provides a novel CO2 mineralization approach that results in (1) effective and practical solutions of carbon dioxide (CO2) emission management and which holds (2) great potential for novel carbon-based fuels development.


Assuntos
Dióxido de Carbono , Óxido de Magnésio , Adsorção , Hidróxido de Magnésio , Pós
15.
Chemistry ; 26(43): 9459-9465, 2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-32167602

RESUMO

Protein folding quality control in cells requires the activity of a class of proteins known as molecular chaperones. Heat shock protein-90 (Hsp90), a multidomain ATP driven molecular machine, is a prime representative of this family of proteins. Interactions between Hsp90, its co-chaperones, and client proteins have been shown to be important in facilitating the correct folding and activation of clients. Hsp90 levels and functions are elevated in tumor cells. Here, we computationally predict the regions on the native structures of clients c-Abl, c-Src, Cdk4, B-Raf and Glucocorticoid Receptor, that have the highest probability of undergoing local unfolding, despite being ordered in their native structures. Such regions represent potential ideal interaction points with the Hsp90-system. We synthesize mimics spanning these regions and confirm their interaction with partners of the Hsp90 complex (Hsp90, Cdc37 and Aha1) by Nuclear Magnetic Resonance (NMR). Designed mimics selectively disrupt the association of their respective clients with the Hsp90 machinery, leaving unrelated clients unperturbed and causing apoptosis in cancer cells. Overall, selective targeting of Hsp90 protein-protein interactions is achieved without causing indiscriminate degradation of all clients, setting the stage for the development of therapeutics based on specific chaperone:client perturbation.


Assuntos
Carcinógenos/química , Proteínas de Ciclo Celular/química , Chaperoninas/química , Proteínas de Choque Térmico HSP90/química , Chaperonas Moleculares/química , Carcinógenos/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Dobramento de Proteína
16.
Clin Infect Dis ; 68(6): 913-918, 2019 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-29986091

RESUMO

BACKGROUND: Treponemal immunoassays are increasingly used for syphilis screening with the reverse sequence algorithm. There are few data describing performance of treponemal immunoassays compared to traditional treponemal tests in patients with and without syphilis. METHODS: We calculated sensitivity and specificity of 7 treponemal assays: (1) ADVIA Centaur (chemiluminescence immunoassay [CIA]); (2) Bioplex 2200 (microbead immunoassay); (3) fluorescent treponemal antibody absorption test (FTA-ABS); (4) INNO-LIA (line immunoassay); (5) LIAISON CIA; (6) Treponema pallidum particle agglutination assay (TPPA); and (7) Trep-Sure (enzyme immunoassay [EIA]), using a reference standard combining clinical diagnosis and serology results. Sera were collected between May 2012-January 2013. Cases were characterized as: (1) current clinical diagnosis of syphilis: primary, secondary, early latent, late latent; (2) prior treated syphilis only; (3) no evidence of current syphilis, no prior history of syphilis, and at least 4 of 7 treponemal tests negative. RESULTS: Among 959 participants, 262 had current syphilis, 294 had prior syphilis, and 403 did not have syphilis. FTA-ABS was less sensitive for primary syphilis (78.2%) than the immunoassays or TPPA (94.5%-96.4%) (all P ≤ .01). All immunoassays were 100% sensitive for secondary syphilis, 95.2%-100% sensitive for early latent disease, and 86.8%-98.5% sensitive in late latent disease. TPPA had 100% specificity. CONCLUSIONS: Treponemal immunoassays demonstrated excellent sensitivity for secondary, early latent, and seropositive primary syphilis. Sensitivity of FTA-ABS in primary syphilis was poor. Given its high specificity and superior sensitivity, TPPA is preferred to adjudicate discordant results with the reverse sequence algorithm over the FTA-ABS.


Assuntos
Imunoensaio , Sorodiagnóstico da Sífilis , Sífilis/diagnóstico , Sífilis/microbiologia , Treponema pallidum , Adulto , Algoritmos , Coinfecção , Feminino , Humanos , Imunoensaio/métodos , Imunoensaio/normas , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Sífilis/epidemiologia , Sorodiagnóstico da Sífilis/métodos , Sorodiagnóstico da Sífilis/normas , Treponema pallidum/imunologia
17.
Curr Opin Infect Dis ; 32(5): 407-412, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31305490

RESUMO

PURPOSE OF REVIEW: This is a review of tafenoquine, a new antimalarial drug. Here we examine the recent literature supporting the use of tafenoquine and summarize the opportunities and challenges for its well tolerated use worldwide. RECENT FINDINGS: Tafenoquine was recently approved by the US Food and Drug Administration for the treatment of dormant liver stage (hypnozoite) in Plasmodium vivax and for malaria prophylaxis. Single-dose tafenoquine provides equivalent efficacy to 14 days of primaquine for radical cure in P. vivax, and it can be dosed weekly to prevent malaria. However, tafenoquine can only be used in patients with normal G6PD activity and is contraindicated in children and during pregnancy or in lactating mothers with infants of deficient or unknown G6PD status. SUMMARY: Tafenoquine's long half-life allows a single dose to achieve radical cure, and weekly dosing for chemoprophylaxis to provide an exciting therapeutic option for patient care and as a new weapon for malaria control/eradication programs. Global implementation of tafenoquine will require the development and validation of a robust, low-cost diagnostic to reliably identify G6PD-deficient individuals. In addition, studies on tafenoquine safety in children are needed.


Assuntos
Aminoquinolinas/administração & dosagem , Antimaláricos/administração & dosagem , Quimioprevenção/métodos , Tratamento Farmacológico/métodos , Malária Vivax/tratamento farmacológico , Malária Vivax/prevenção & controle , Aminoquinolinas/efeitos adversos , Aminoquinolinas/farmacocinética , Antimaláricos/efeitos adversos , Antimaláricos/farmacocinética , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Humanos
18.
World J Urol ; 37(10): 2099-2108, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30671637

RESUMO

PURPOSE: Although prediction tools for prostate cancer (PCa) are essential for high-quality treatment decision-making, little is known about the degree of confidence in existing tools and whether they are used in clinical practice from radiation oncologists (RO) and urologists (URO). Herein, we performed a national survey of specialists about perceived attitudes and use of prediction tools. METHODS: In 2017, we invited 940 URO and 911 RO in a national survey to query their confidence in and use of the D'Amico criteria, Kattan Nomogram, and CAPRA score. The statistical analysis involved bivariate association and multivariable logistic regression analyses to identify physician characteristics (age, gender, race, practice affiliation, specialty, access to robotic surgery, ownership of linear accelerator and number of prostate cancer per week) associated with survey responses and use of active surveillance (AS) for low-risk PCa. RESULTS: Overall, 691 (37.3%) specialists completed the surveys. Two-thirds (range 65.6-68.4%) of respondents reported being "somewhat confident", but only a fifth selected "very confident" for each prediction tool (18.0-20.1%). 19.1% of specialists in the survey reported not using any prediction tools in clinical practice, which was higher amongst URO than RO (23.9 vs. 13.4%; p < 0.001). Respondents who reported not using prediction tools were also associated with low utilization of AS in their low-risk PCa patients (adjusted OR 2.47; p = 0.01). CONCLUSIONS: While a majority of RO and URO view existing prediction tools for localized PCa with some degree of confidence, a fifth of specialists reported not using any such tools in clinical practice. Lack of using such tools was associated with low utilization of AS for low-risk PCa.


Assuntos
Atitude do Pessoal de Saúde , Oncologia , Nomogramas , Neoplasias da Próstata/terapia , Radiologia , Urologia , Adulto , Idoso , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Estados Unidos
20.
Invest New Drugs ; 32(5): 955-68, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24942404

RESUMO

LY2603618 is an inhibitor of checkpoint kinase 1 (CHK1), an important regulator of the DNA damage checkpoints. Preclinical experiments analyzed NCI-H2122 and NCI-H441 NSCLC cell lines and in vitro/in vivo models treated with pemetrexed and LY2603618 to provide rationale for evaluating this combination in a clinical setting. Combination treatment of LY2603618 with pemetrexed arrested DNA synthesis following initiation of S-phase in cells. Experiments with tumor-bearing mice administered the combination of LY2603618 and pemetrexed demonstrated a significant increase of growth inhibition of NCI-H2122 (H2122) and NCI-H441 (H441) xenograft tumors. These data informed the clinical assessment of LY2603618 in a seamless phase I/II study, which administered pemetrexed (500 mg/m(2)) and cisplatin (75 mg/m(2)) and escalating doses of LY2603618: 130-275 mg. Patients were assessed for safety, toxicity, and pharmacokinetics. In phase I, 14 patients were enrolled, and the most frequently reported adverse events included fatigue, nausea, pyrexia, neutropenia, and vomiting. No DLTs were reported at the tested doses. The systemic exposure of LY2603618 increased in a dose-dependent manner. Pharmacokinetic parameters that correlate with the maximal pharmacodynamic effect in nonclinical xenograft models were achieved at doses ≥240 mg. The pharmacokinetics of LY2603618, pemetrexed, and cisplatin were not altered when used in combination. Two patients achieved a confirmed partial response (both non-small cell lung cancer), and 8 patients had stable disease. LY2603618 administered in combination with pemetrexed and cisplatin demonstrated an acceptable safety profile. The recommended phase II dose of LY2603618 was 275 mg.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias/tratamento farmacológico , Adulto , Idoso , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/sangue , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Linhagem Celular Tumoral , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Cisplatino/sangue , Cisplatino/farmacocinética , DNA/metabolismo , Feminino , Glutamatos/administração & dosagem , Glutamatos/efeitos adversos , Glutamatos/sangue , Glutamatos/farmacocinética , Guanina/administração & dosagem , Guanina/efeitos adversos , Guanina/análogos & derivados , Guanina/sangue , Guanina/farmacocinética , Humanos , Masculino , Camundongos Nus , Pessoa de Meia-Idade , Neoplasias/sangue , Neoplasias/patologia , Pemetrexede , Compostos de Fenilureia/administração & dosagem , Compostos de Fenilureia/efeitos adversos , Compostos de Fenilureia/sangue , Compostos de Fenilureia/farmacocinética , Pirazinas/administração & dosagem , Pirazinas/efeitos adversos , Pirazinas/sangue , Pirazinas/farmacocinética , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
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