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2.
Nature ; 583(7818): 801-806, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32699418

RESUMO

Decades of overexploitation have devastated shark populations, leaving considerable doubt as to their ecological status1,2. Yet much of what is known about sharks has been inferred from catch records in industrial fisheries, whereas far less information is available about sharks that live in coastal habitats3. Here we address this knowledge gap using data from more than 15,000 standardized baited remote underwater video stations that were deployed on 371 reefs in 58 nations to estimate the conservation status of reef sharks globally. Our results reveal the profound impact that fishing has had on reef shark populations: we observed no sharks on almost 20% of the surveyed reefs. Reef sharks were almost completely absent from reefs in several nations, and shark depletion was strongly related to socio-economic conditions such as the size and proximity of the nearest market, poor governance and the density of the human population. However, opportunities for the conservation of reef sharks remain: shark sanctuaries, closed areas, catch limits and an absence of gillnets and longlines were associated with a substantially higher relative abundance of reef sharks. These results reveal several policy pathways for the restoration and management of reef shark populations, from direct top-down management of fishing to indirect improvement of governance conditions. Reef shark populations will only have a high chance of recovery by engaging key socio-economic aspects of tropical fisheries.


Assuntos
Conservação dos Recursos Naturais/estatística & dados numéricos , Recifes de Corais , Ecossistema , Pesqueiros/economia , Pesqueiros/estatística & dados numéricos , Tubarões/fisiologia , Animais , Mapeamento Geográfico , Densidade Demográfica , Fatores Socioeconômicos
3.
Clin Infect Dis ; 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38465901

RESUMO

BACKGROUND: The purpose of this study was to evaluate whether the 2023-2024 formulation of the COVID-19 mRNA vaccine protects against COVID-19. METHODS: Employees of Cleveland Clinic in employment when the 2023-2024 formulation of the COVID-19 mRNA vaccine became available to employees, were included. Cumulative incidence of COVID-19 over the following 17 weeks was examined prospectively. Protection provided by vaccination (analyzed as a time-dependent covariate) was evaluated using Cox proportional hazards regression, with time-dependent coefficients used to separate effects before and after the JN.1 lineage became dominant. The analysis was adjusted for the propensity to get tested, age, sex, pandemic phase when the last prior COVID-19 episode occurred, and the number of prior vaccine doses. RESULTS: Among 48210 employees, COVID-19 occurred in 2462 (5.1%) during the 17 weeks of observation. In multivariable analysis, the 2023-2024 formula vaccinated state was associated with a significantly lower risk of COVID-19 before the JN.1 lineage became dominant (HR, .58; 95% C.I., .49-.68, p-value < .001), and lower risk but one that did not reach statistical significance after (HR, .81; 95% C.I., .65-1.01, p-value 0.06). Estimated vaccine effectiveness (VE) was 42% (95% C.I., 32%-51%) before the JN.1 lineage became dominant, and 19% (C.I., -1%-35%) after. Risk of COVID-19 was lower among those previously infected with an XBB or more recent lineage, and increased with the number of vaccine doses previously received. CONCLUSIONS: The 2023-2024 formula COVID-19 vaccine given to working-aged adults afforded modest protection overall against COVID-19 before the JN.1 lineage became dominant, and less protection after.

4.
Eur J Haematol ; 112(3): 424-432, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37929654

RESUMO

Aplastic anemia (AA) is a rare bone marrow failure disorder that is treated with either allogeneic stem cell transplant or immunosuppressive therapy (IST) consisting of antithymocyte globulin (ATG), cyclosporine (CSA), and eltrombopag. While outcomes are favorable in younger patients, older patients (>60) have significantly worse long-term survival. The dose of ATG is often reduced in older patients and those with multiple comorbidities given concerns for tolerability. The efficacy and safety of dose-attenuated IST in this population is largely undescribed. We performed a retrospective review of patients with AA treated with IST. Our analysis was confounded by changes in practice patterns and the introduction of eltrombopag. We identified 53 patients >60 years old, of which, 20 received dose-attenuated IST, with no statistically significant difference in overall survival between full and attenuated dose cohorts. Overall response rates in both cohorts were similar at 6 months at 71% and 68%. There were more documented infectious complications in the full dose cohort (13 vs. 3). This supports the consideration of dose-attenuated IST in older patients with concerns about tolerance of IST. Lastly, our data confirmed favorable outcomes of younger patients receiving IST, especially in combination with eltrombopag.


Assuntos
Anemia Aplástica , Benzoatos , Hidrazinas , Imunossupressores , Pirazóis , Humanos , Idoso , Pessoa de Meia-Idade , Imunossupressores/efeitos adversos , Anemia Aplástica/diagnóstico , Anemia Aplástica/tratamento farmacológico , Resultado do Tratamento , Ciclosporina/efeitos adversos , Terapia de Imunossupressão , Soro Antilinfocitário/efeitos adversos
5.
J Anim Ecol ; 93(4): 447-459, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38348546

RESUMO

Predation risk is a function of spatiotemporal overlap between predator and prey, as well as behavioural responses during encounters. Dynamic factors (e.g. group size, prey availability and animal movement or state) affect risk, but rarely are integrated in risk assessments. Our work targets a system where predation risk is fundamentally linked to temporal patterns in prey abundance and behaviour. For neonatal ungulate prey, risk is defined within a short temporal window during which the pulse in parturition, increasing movement capacity with age and antipredation tactics have the potential to mediate risk. In our coyote-mule deer (Canis latrans-Odocoileus hemionus) system, leveraging GPS data collected from both predator and prey, we tested expectations of shared enemy and reproductive risk hypotheses. We asked two questions regarding risk: (A) How does primary and alternative prey habitat, predator and prey activity, and reproductive tactics (e.g. birth synchrony and maternal defence) influence the vulnerability of a neonate encountering a predator? (B) How do the same factors affect behaviour by predators relative to the time before and after an encounter? Despite increased selection for mule deer and intensified search behaviour by coyotes during the peak in mule deer parturition, mule deer were afforded protection from predation via predator swamping, experiencing reduced per-capita encounter risk when most neonates were born. Mule deer occupying rabbit habitat (Sylvilagus spp.; coyote's primary prey) experienced the greatest risk of encounter but the availability of rabbit habitat did not affect predator behaviour during encounters. Encounter risk increased in areas with greater availability of mule deer habitat: coyotes shifted their behaviour relative to deer habitat, and the pulse in mule deer parturition and movement of neonatal deer during encounters elicited increased speed and tortuosity by coyotes. In addition to the spatial distribution of prey, temporal patterns in prey availability and animal behavioural state were fundamental in defining risk. Our work reveals the nuanced consequences of pulsed availability on predation risk for alternative prey, whereby responses by predators to sudden resource availability, the lasting effects of diversionary prey and inherent antipredation tactics ultimately dictate risk.


Assuntos
Coiotes , Cervos , Animais , Coelhos , Cervos/fisiologia , Coiotes/fisiologia , Ecossistema , Comportamento Predatório/fisiologia , Equidae
6.
J Cancer Educ ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38955941

RESUMO

Patient education in acute myeloid leukemia (AML) has become increasingly complex with the introduction of new treatments and chemotherapy regimens. Video education presents an opportunity to supplement traditional patient education and address some of the gaps associated with standard methods. This single-center study sought to assess the potential impact of supplemental video education on patients receiving induction chemotherapy for AML. Participants were consented to be randomized to receive their education with or without a supplemental video designed for their treatment regimen. We then provided a survey to each participant to assess knowledge retention, anxiety, and overall satisfaction with their care. Patients that received video education were found to have significantly improved knowledge retention compared to those that did not. There were no differences detected in anxiety or patient satisfaction. Video education appears to be an effective supplemental method for patient education in AML. Limitations include the single-center nature of the study at an urban academic medical center with a relatively well-educated, primarily Caucasian, younger population. Future research is warranted to assess the video in a diverse set of languages and to explore its broader benefits.

7.
Haematologica ; 108(3): 705-716, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36226495

RESUMO

Mivavotinib (TAK-659) is an investigational type 1 tyrosine kinase inhibitor with dual activity against spleen tyrosine kinase (SYK) and FMS-like tyrosine kinase 3 (FLT3). We conducted a phase Ib study to investigate the safety, tolerability, and efficacy of mivavotinib in patients with refractory and/or relapsed (R/R) acute myeloid leukemia (AML). Both daily (QD) and twice daily (BID) dosing regimens were evaluated. A total of 43 patients were enrolled, and there were 5 complete responses (4 with incomplete count recovery). In the QD dosing regimen, the maximum tolerated dose (MTD) was not reached up to 160 mg QD per protocol; 140 mg QD was identified as the recommended phase II dose. In the BID dosing regimen, the MTD was 60 mg BID. Thirty patients (70%) experienced a bleeding event on study; the majority were grades 1 or 2, were resolved without mivavotinib modification, and were not considered related to study treatment. Eleven patients (26%) experienced grade ≥3 bleeding events, which were observed most frequently with the 80 mg BID dose. We conducted platelet aggregation studies to investigate the potential role of mivavotinib-mediated SYK inhibition on platelet function. The bleeding events observed may have been the result of several confounding factors, including AML disease status, associated thrombocytopenia, and high doses of mivavotinib. Overall, these findings indicate that the activity of mivavotinib in R/R AML is modest. Furthermore, any future clinical investigation of this agent should be undertaken with caution, particularly in thrombocytopenic patients, due to the potential bleeding risk of SYK inhibition. ClinicalTrials.gov: NCT02323113.


Assuntos
Leucemia Mieloide Aguda , Tirosina Quinase 3 Semelhante a fms , Humanos , Inibidores de Proteínas Quinases/efeitos adversos , Pirimidinas/efeitos adversos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Quinase Syk
8.
Ann Hematol ; 102(11): 3133-3141, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37480389

RESUMO

The incorporation of pediatric-inspired regimens in the adolescent-young-adult (AYA) and adult populations have resulted improved survival outcomes (Stock et al. Blood 133(14):1548-1559 2019; Dunsmore et al. J Clin Oncol 38(28):3282-3293 2020; DeAngelo et al. Leukemia 29(3):526-534 2015). Nonetheless incorporation of such regimens is limited by increased toxicity to asparaginase. Dosing strategies that reduce the weight-based dose of pegylated-L-asparaginase (PEG-asparaginase) utilizing activity monitoring have been shown to result in better tolerability of these regimens. The purpose of this study was to analyze the efficacy and safety of treating adults with Philadelphia chromosome negative (Ph-) ALL with pediatric-inspired regimens that incorporate PEG-asparaginase dose adjustments and asparaginase activity level monitoring. Patients aged 18-65 years initiated on pediatric-inspired regimens utilizing dose-reduced PEG-asparaginase with therapeutic drug monitoring-guided adjustments were included. The screening of 122 patients treated between 2015 and 2021 resulted in the inclusion of 54 patients. The median age of the cohort was 35 years (16-65 years), and median body mass index (BMI) was 30 kg/m2 (18.3-53.4 kg/m2). The 36-month survival estimate was 62.1% (95% CI 48.1-77.7%), and the median overall survival (OS) was 62.2 months (95% CI 35.1-89.3 months). In the AYA cohort, the 36-month survival was 71.2% (95% CI 55.8-91%) and the median overall survival was not reached. Survival was not significantly affected by immunophenotype or BMI. Discontinuation due to toxicity or hypersensitivity reactions was low at 11% and 9% respectively. The encouraging survival outcomes and favorable tolerability of this older population in the real-world setting support the use of individualized PEG-asparaginase dosing with PharmD-guided therapeutic drug monitoring.


Assuntos
Asparaginase , Monitoramento de Medicamentos , Adolescente , Adulto , Humanos , Asparaginase/efeitos adversos , Polietilenoglicóis/efeitos adversos , Índice de Massa Corporal
9.
Clin Infect Dis ; 75(12): 2169-2177, 2022 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-35476018

RESUMO

BACKGROUND: The purpose of this study was to determine whether boosting previously infected or vaccinated individuals with a vaccine developed for an earlier variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) protects against the Omicron variant. METHODS: Employees of Cleveland Clinic, previously infected with or vaccinated against coronavirus disease 2019 (COVID-19) and working the day the Omicron variant was declared a variant of concern, were included. The cumulative incidence of COVID-19 was examined over 2 months during an Omicron variant surge. Protection provided by boosting was evaluated using Cox proportional hazards regression. Analyses were adjusted for time since proximate SARS-CoV-2 exposure. RESULTS: Among 39 766 employees, 8037 (20%) previously infected and the remaining previously vaccinated, COVID-19 occurred in 6230 (16%) during the study. Risk of COVID-19 increased with time since proximate SARS-CoV-2 exposure, and boosting protected those >6 months since prior infection or vaccination. In multivariable analysis, boosting was independently associated with lower risk of COVID-19 among those vaccinated but not previously infected (hazard ratio [HR], .43; 95% confidence interval [CI], .41-.46) as well as those previously infected (HR, .66; 95% CI, .58-.76). Among those previously infected, receipt of 2 compared with 1 dose of vaccine was associated with higher risk of COVID-19 (HR, 1.54; 95% CI, 1.21-1.97). CONCLUSIONS: Administering a COVID-19 vaccine not designed for the Omicron variant >6 months after prior infection or vaccination protects against Omicron variant infection. There is no advantage to administering more than 1 dose of vaccine to previously infected persons.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , SARS-CoV-2 , Instituições de Assistência Ambulatorial
10.
Clin Infect Dis ; 75(1): e662-e671, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-35028662

RESUMO

BACKGROUND: The aim was to evaluate the necessity of coronavirus disease 2019 (COVID-19) vaccination in persons with prior COVID-19. METHODS: Employees of the Cleveland Clinic working in Ohio on 16 December 2020, the day COVID-19 vaccination was started, were included. Anyone who tested positive for COVID-19 at least once before the study start date was considered previously infected. One was considered vaccinated 14 days after receiving the second dose of COVID-19 mRNA vaccine. Cumulative incidences of COVID-19, symptomatic COVID-19, and hospitalizations for COVID-19 were examined over the next year. RESULTS: Among 52 238 employees, 4718 (9%) were previously infected and 36 922 (71%) were vaccinated by the study's end. Cumulative incidence of COVID-19 was substantially higher throughout for those previously uninfected who remained unvaccinated than for all other groups, lower for the vaccinated than unvaccinated, and lower for those previously infected than those not. Incidence of COVID-19 increased dramatically in all groups after the Omicron variant emerged. In multivariable Cox proportional hazards regression, both prior COVID-19 and vaccination were independently associated with significantly lower risk of COVID-19. Among previously infected subjects, a lower risk of COVID-19 overall was not demonstrated, but vaccination was associated with a significantly lower risk of symptomatic COVID-19 in both pre-Omicron (HR, .60; 95% CI, .40-.90) and Omicron (HR, .36; 95% CI, .23-.57) phases. CONCLUSIONS: Both previous infection and vaccination provide substantial protection against COVID-19. Vaccination of previously infected individuals does not provide additional protection against COVID-19 for several months, but after that provides significant protection at least against symptomatic COVID-19.


Assuntos
COVID-19 , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Humanos , SARS-CoV-2 , Vacinação , Vacinas Sintéticas , Vacinas de mRNA
11.
Ann Hematol ; 101(8): 1627-1644, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35618780

RESUMO

In recent years, an explosion of novel agents has shifted the treatment paradigm for patients with acute myeloid leukemia. The optimal place in therapy for many of these novel agents remains unknown due to limited guidance from national guidelines and the way these agents were studied prior to entering the market. A critical evaluation of the literature and incorporation of oncology stewardship principles can be helpful in determining an optimal place for these agents while being mindful of the overall cost that is associated with therapies. The purpose of this review is to critically evaluate the efficacy and safety data for five controversial agents and provide examples of the use of stewardship practices in determining their place in the treatment of acute myeloid leukemia.


Assuntos
Leucemia Mieloide Aguda , Oncologia , Humanos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/tratamento farmacológico
12.
Ecol Appl ; 32(7): e2648, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35535971

RESUMO

Understanding factors that influence animal behavior is central to ecology. Basic principles of animal ecology imply that individuals should seek to maximize survival and reproduction, which means carefully weighing risk against reward. Decisions become increasingly complex and constrained, however, when risk is spatiotemporally variable. We advance a growing body of work in predator-prey behavior by evaluating novel questions where a prey species is confronted with multiple predators and a potential competitor. We tested how fine-scale behavior of female mule deer (Odocoileus hemionus) during the reproductive season shifted depending upon spatial and temporal variation in risk from predators and a potential competitor. We expected female deer to avoid areas of high risk when movement activity of predators and a competitor were high. We used GPS data collected from 76 adult female mule deer, 35 adult female elk, 33 adult coyotes, and six adult mountain lions. Counter to our expectations, female deer exhibited selection for multiple risk factors, however, selection for risk was dampened by the exposure to risk within home ranges of female deer, producing a functional response in habitat selection. Furthermore, temporal variation in movement activity of predators and elk across the diel cycle did not result in a shift in movement activity by female deer. Instead, the average level of risk within their home range was the predominant factor modulating the response to risk by female deer. Our results counter prevailing hypotheses of how large herbivores navigate risky landscapes and emphasize the importance of accounting for the local environment when identifying effects of risk on animal behavior. Moreover, our findings highlight additional behavioral mechanisms used by large herbivores to mitigate multiple sources of predation and potential competitive interactions.


Assuntos
Coiotes , Cervos , Animais , Cervos/fisiologia , Ecossistema , Equidae , Feminino , Herbivoria , Comportamento Predatório
13.
J Oncol Pharm Pract ; 28(6): 1315-1325, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34074182

RESUMO

BACKGROUND: Patients diagnosed with acute myeloid leukemia with a FLT3 mutation (FLT3+ AML) have historically had poor outcomes. While the addition of the FLT3 inhibitors to induction therapy has been shown to improve survival outcomes in FLT3+ AML, interactions and overlapping toxicities between FLT3 inhibitors and standard of care medications used during induction therapy (e.g. azole antifungals, anthracyclines) and logistical barriers have complicated their use. To avoid these concerns, our institution has opted to defer initiation of midostaurin until after completion of induction therapy. However, to our knowledge no study confirming the effectiveness of this strategy for real world FLT3 inhibitor use has been published. METHODS: We performed a single center, propensity-score matched, retrospective cohort study characterizing efficacy and safety of our strategy for use of FLT3 inhibitors in the treatment of FLT3+ AML. The primary outcome was median event-free survival (EFS), while secondary endpoints included median overall survival (OS), overall response rate (ORR), 30-day mortality, duration of neutropenia, duration of thrombocytopenia, consolidation cycle delays, documented infections, and all-cause hospital readmission. RESULTS: A total of 83 FLT3+ AML patients treated with intensive induction therapy were included in the study, of whom 48 were propensity-score matched and analyzed. Baseline characteristics were similar between the patients who received a FLT3 inhibitor after induction therapy and the historical control arm. Median EFS was not significantly different but compared favorably between the FLT3 inhibitor cohort and historical controls (not reached vs 8 months, p = 0.343) with 18-month EFS of 54% and 43% for the two cohorts, respectively. Similarly, no significant differences were noted with regard to median OS (not reached vs 28.7 months, p = 0.752), ORR (79.2% vs 79.2%), or safety outcomes between groups. CONCLUSION: Compared to historical controls, addition of a FLT3 inhibitor to intensive chemotherapy post-induction may improve EFS or OS in a real world patient cohort with longer follow-up and a larger sample size. The omission of midostaurin in induction allowed for the use of an azole antifungal and the intensification of anthracycline dose may have contributed to high remission rates in both groups.


Assuntos
Leucemia Mieloide Aguda , Azóis/uso terapêutico , Estudos de Coortes , Humanos , Leucemia Mieloide Aguda/genética , Mutação , Inibidores de Proteínas Quinases/uso terapêutico , Estudos Retrospectivos , Tirosina Quinase 3 Semelhante a fms/genética
14.
J Natl Compr Canc Netw ; 19(9): 1079-1109, 2021 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-34551384

RESUMO

The NCCN Guidelines for Acute Lymphoblastic Leukemia (ALL) focus on the classification of ALL subtypes based on immunophenotype and cytogenetic/molecular markers; risk assessment and stratification for risk-adapted therapy; treatment strategies for Philadelphia chromosome (Ph)-positive and Ph-negative ALL for both adolescent and young adult and adult patients; and supportive care considerations. Given the complexity of ALL treatment regimens and the required supportive care measures, the NCCN ALL Panel recommends that patients be treated at a specialized cancer center with expertise in the management of ALL This portion of the Guidelines focuses on the management of Ph-positive and Ph-negative ALL in adolescents and young adults, and management in relapsed settings.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras , Adolescente , Humanos , Imunofenotipagem , Oncologia , Cromossomo Filadélfia , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Adulto Jovem
15.
Transpl Infect Dis ; 23(4): e13612, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33825279

RESUMO

BACKGROUND: Current literature has demonstrated the utility of the MRSA nasal screen as a de-escalation tool to decrease unnecessary anti-MRSA antibiotic therapy. However, data on the applicability of this test in patients with hematologic malignancy is lacking. METHODS: This is a single-center, retrospective cohort study of patients with acute myeloid leukemia (AML) with or without a history of hematopoietic cell transplant (HCT), with pneumonia and MRSA nasal screening with respiratory cultures obtained. The primary outcome was to determine the negative predictive value (NPV) of the MRSA nasal screen for MRSA pneumonia. Secondary outcomes included sensitivity, specificity, positive predictive value (PPV) of the MRSA nasal screen and prevalence of MRSA pneumonia. RESULTS: Of 98 patients with AML and pneumonia, the prevalence of MRSA pneumonia was 4.1% with confirmed positive MRSA respiratory cultures observed in 4 patient cases. In patients with confirmed MRSA pneumonia, 3 had positive MRSA nasal screens while 1 had a false negative result, possibly due to a long lag time (21 days) between MRSA nasal screen and pneumonia diagnosis. Overall, the MRSA nasal screen demonstrated 75% sensitivity and 100% specificity, with a PPV of 100% and a NPV of 98.9%. CONCLUSIONS: Given the low prevalence, empiric use of anti-MRSA therapy in those AML and HCT patients with pneumonia may not be warranted in clinically stable patients. For patients in whom empiric anti-MRSA antibiotics are initiated, nasal screening for MRSA may be utilized to de-escalate anti-MRSA antibiotics in patients with AML with or without HCT.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Staphylococcus aureus Resistente à Meticilina , Pneumonia Estafilocócica , Infecções Estafilocócicas , Antibacterianos/uso terapêutico , Humanos , Leucemia Mieloide Aguda/complicações , Leucemia Mieloide Aguda/tratamento farmacológico , Pneumonia Estafilocócica/tratamento farmacológico , Estudos Retrospectivos , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/epidemiologia
16.
J Fish Biol ; 99(1): 271-274, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33534180

RESUMO

Prey manipulation through headfirst ingestion is a common foraging tactic in predatory taxa. Sawsharks possess a toothed rostrum that is thought to assist in prey capture, but the process from prey contact to ingestion is unknown. This study provides evidence of headfirst ingestion and possible prey orientation in situ through the use of cone beam CT scans in the common sawshark (Pristiophorus cirratus). CT scans provide an efficient method for assessing ingestion and proposing plausible behavioural tactics for food manipulation in a species difficult to observe in the wild or maintain in captivity.


Assuntos
Elasmobrânquios , Dente , Animais , Tomografia Computadorizada de Feixe Cônico , Ingestão de Alimentos , Comportamento Predatório
17.
Toxicol Appl Pharmacol ; 392: 114932, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32109510

RESUMO

Recently, we described a family of non-targeting monomethylauristatin E (MMAE) antibody-drug conjugates (ADCs) whose pharmacokinetics could be tuned through incorporation of a short polyethylene glycol (PEG) moiety of up to twelve units into a drug-linker to render the ADC surface more hydrophilic. That work demonstrated that more hydrophilic ADCs were simultaneously more effective and better tolerated in mouse models, suggesting an improvement in therapeutic index via this strategy. Here, we describe the biodistribution and toxicology assessments in Sprague-Dawley rats after intravenous dosing with the aim of elucidating the relationships between these biological outcomes and the underlying physicochemical properties of non-targeted ADCs. Dosing a non-PEGylated ADC exhibited rapid nonspecific cellular uptake, leading to ADC catabolism and rapid release of the cytotoxic payload which reached peak plasma and tissue concentrations within the first day. Introduction of a PEG chain of four, eight, or twelve units resulted in increasingly slower uptake and decreases in peak payload concentrations in all tissues. These ADCs with minimal non-specific uptake also exhibited substantially less hematologic toxicity, with reduced histologic depletion of bone marrow and less dramatic decreases and/or more rapid recovery in peripheral hematologic cell counts (neutrophils, platelets, and reticulocytes). These results support a strong correlation between ADC hydrophobicity, rate of non-specific uptake, peak tissue concentration of released payload, and resulting toxicology parameters. Should these correlations be translatable to the clinic, this would provide a more general and highly tractable strategy for reducing the antigen-independent toxicity of ADCs through drug-linker design to modulate non-specific biodistribution.


Assuntos
Imunoconjugados/química , Imunoconjugados/farmacocinética , Oligopeptídeos/administração & dosagem , Oligopeptídeos/farmacocinética , Polietilenoglicóis/química , Animais , Feminino , Imunoconjugados/administração & dosagem , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual
18.
Bioorg Med Chem Lett ; 30(14): 127241, 2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32527543

RESUMO

The tubulysins are an emerging antibody-drug conjugate (ADC) payload that maintain potent anti-proliferative activity against cells that exhibit the multi-drug resistant (MDR) phenotype. These drugs possess a C-11 acetate known to be hydrolytically unstable in plasma, and loss of the acetate significantly attenuates cytotoxicity. Structure-activity relationship studies were undertaken to identify stable C-11 tubulysin analogues that maintain affinity for tubulin and potent cytotoxicity. After identifying several C-11 alkoxy analogues that possess comparable biological activity to tubulysin M with significantly improved plasma stability, additional analogues of both the Ile residue and N-terminal position were synthesized. These studies revealed that minor changes within the tubulin binding site of tubulysin can profoundly alter the activity of this chemotype, particularly against MDR-positive cell types.


Assuntos
Antineoplásicos/farmacologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Oligopeptídeos/farmacologia , Antineoplásicos/sangue , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Oligopeptídeos/sangue , Oligopeptídeos/química , Relação Estrutura-Atividade
19.
Sleep Breath ; 24(4): 1357-1363, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31792908

RESUMO

PURPOSE: The negative association between obstructive sleep apnea (OSA) and adverse cardiovascular outcomes in patients undergoing percutaneous coronary intervention (PCI) is well documented. However, little is known about the influence of OSA on fibrinolytic therapy. The aim of this study was to evaluate the impact of severe OSA on pharmacoinvasive treatment in ST elevation myocardial infarction (STEMI) patients. METHODS: We enrolled consecutive STEMI patients without previous vascular disease, heart failure, or OSA diagnosis. All patients underwent either a pharmacoinvasive therapy or primary PCI. Syntax score (SS) was calculated for all patients, and a full bedside polysomnography was performed in the first 72 h of admission. In-hospital events and 30 days readmissions were analyzed. RESULTS: The sample included 116 patients, 87 men. Patients with severe OSA were older (p = 0.01), had higher neck and abdominal circumferences (p < 0.01), and had higher BMI (p < 0.01). They also had lower reperfusion rates post-fibrinolysis (20 vs. 65%; p = 0.001), higher SS (20.2 ± 11.2 vs. 14.6 ± 10.6; p = 0.03), lower left ventricle ejection fraction (45 ± 8 vs. 51 ± 10%; p = 0.02), and a higher incidence of atrial arrhythmias (4 vs. 21%; p = 0.02). STEMI patients with severe OSA presented with threefold increase in the risk for at least one adverse outcome. Regression analysis showed that both severe OSA and hypertension were independent predictors of higher SS. CONCLUSION: Severe OSA was associated with a poor outcome after pharmacoinvasive treatment in STEMI patients.


Assuntos
Fibrinolíticos/efeitos adversos , Infarto do Miocárdio com Supradesnível do Segmento ST/complicações , Infarto do Miocárdio com Supradesnível do Segmento ST/tratamento farmacológico , Apneia Obstrutiva do Sono/complicações , Terapia Trombolítica/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Resultado do Tratamento
20.
Ann Hematol ; 98(3): 541-559, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30666431

RESUMO

Secondary AML is associated with a disproportionately poor prognosis, consistently shown to exhibit inferior response rates, event-free survival, and overall survival in comparison with de novo AML. Secondary AML may arise from the evolution of an antecedent hematologic disorder, or it may arise as a complication of prior cytotoxic chemotherapy or radiation therapy in the case of therapy-related AML. Because of the high frequency of poor-risk cytogenetics and high-risk molecular features, such as alterations in TP53, leukemic clones are often inherently chemoresistant. Standard of care induction had long remained conventional 7 + 3 until its reformulation as CPX-351, recently FDA approved specifically for secondary AML. However, recent data also suggests relatively favorable outcomes with regimens based on high-dose cytarabine or hypomethylating agents. With several investigational agents being studied, the therapeutic landscape becomes even more complex, and the treatment approach involves patient-specific, disease-specific, and therapy-specific considerations.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Citarabina/uso terapêutico , Daunorrubicina/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Animais , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Mutação , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
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