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2.
Br J Haematol ; 204(4): 1422-1428, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38176404

RESUMO

The standard of care for fit, newly diagnosed multiple myeloma patients includes induction therapy followed by consolidative high-dose chemotherapy with melphalan and autologous stem cell transplant (AHSCT). Intensified preparative regimens, such as busulfan and melphalan (BuMel), have shown promise to lengthen progression-free survival (PFS). We previously reported that the addition of bortezomib to BuMel improved PFS compared to melphalan alone in CIBMTR-matched controls. We now integrate the second-generation protease inhibitor, carfilzomib, before and after BuMel (BuMelCar) in a phase I/II trial with carfilzomib. Patients with NDMM, relapsed/refractory MM (RRMM) and those failing prior AHSCT were eligible. Primary end-points were safety and tolerability. Secondary end-points included minimal residual disease negativity rates, PFS and OS. The study enrolled 19 patients. 73% were high risk either due to R-ISS III status, adverse genetics or relapsed after prior AHSCT. The maximum tolerated dose (MTD) of carfilzomib was determined to be 36 mg/m2. Noted grade 3 toxicities were febrile neutropenia (79%), mucositis (21%) and diarrhoea (16%). The 2-year PFS for the whole cohort and MTD was 89% and 100% respectively. 80% of all patients and 82% of patients in the MTD cohort achieved MRD negativity. Further studies regarding this regimen are planned.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Mieloma Múltiplo , Oligopeptídeos , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Bussulfano , Melfalan , Mieloma Múltiplo/tratamento farmacológico , Transplante de Células-Tronco , Transplante Autólogo
3.
NPJ Regen Med ; 8(1): 52, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37726307

RESUMO

Tendons are essential, frequently injured connective tissues that transmit forces from muscle to bone. Their unique highly ordered, matrix-rich structure is critical for proper function. While adult mammalian tendons heal after acute injuries, endogenous tendon cells, or tenocytes, fail to respond appropriately, resulting in the formation of disorganized fibrovascular scar tissue with impaired function and increased propensity for re-injury. Here, we show that, unlike mammals, adult zebrafish tenocytes activate upon injury and fully regenerate the tendon. Using a full tear injury model in the adult zebrafish craniofacial tendon, we defined the hallmark stages and cellular basis of tendon regeneration through multiphoton imaging, lineage tracing, and transmission electron microscopy approaches. Remarkably, we observe that zebrafish tendons regenerate and restore normal collagen matrix ultrastructure by 6 months post-injury (mpi). Tendon regeneration progresses in three main phases: inflammation within 24 h post-injury (hpi), cellular proliferation and formation of a cellular bridge between the severed tendon ends at 3-5 days post-injury (dpi), and re-differentiation and matrix remodeling beginning from 5 dpi to 6 mpi. Importantly, we demonstrate that pre-existing tenocytes are the main cellular source of regeneration, proliferating and migrating upon injury to ultimately bridge the tendon ends. Finally, we show that TGF-ß signaling is required for tenocyte recruitment and bridge formation. Collectively, our work debuts and aptly positions the adult zebrafish tendon as an invaluable comparative system to elucidate regenerative mechanisms that may inspire new therapeutic strategies.

4.
Alcohol Alcohol ; 58(5): 472-477, 2023 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-37565935

RESUMO

BACKGROUND: Therapies to prevent alcohol-associated liver disease (ALD) in high-risk patients are needed. AIMS: In this retrospective association study, we examined whether patients with alcohol use disorder (AUD) who reported greater exercise were less likely to develop liver disease. METHODS: In this retrospective cohort study, we used the Mass General Brigham Biobank to investigate the impact of both moderate-high and light-intensity exercise on the development of ALD in patients with AUD, using clinician-provided diagnostic International Classification of Diseases 10 codes. Exercise was evaluated using a questionnaire completed after an AUD diagnosis, and before evidence of liver disease. Cox regressions were used to generate hazard ratios (HRs) for the development of ALD. RESULTS: 1987 patients met inclusion criteria. These patients were followed for an average of 10.7 years. In multivariable analyses, we found that patients that reported at least 2.5 h of moderate-high intensity exercise/week (confidence interval recommendation for exercise) were less likely to develop ALD compared to patients that did not exercise (HR: 0.26, 95%CI: 0.085-0.64, P = 0.007). Indeed, each hour of moderate-high intensity exercise was associated with progressively decreasing odds of developing ALD (HR: 0.76, 95%CI: 0.58-0.91, P = 0.02). Conversely, patients who did not engage in any moderate-high intensity exercise were more likely to develop ALD (HR: 2.76, 95%CI: 1.44-5.40, P = 0.003). CONCLUSIONS: In our cohort, patients with AUD who reported moderate-high intensity exercise showed a lower association with incidence of ALD development than patients who did not exercise.


Assuntos
Alcoolismo , Hepatopatias Alcoólicas , Transplante de Fígado , Humanos , Estudos Retrospectivos , Hepatopatias Alcoólicas/complicações , Consumo de Bebidas Alcoólicas/efeitos adversos , Alcoolismo/epidemiologia , Alcoolismo/complicações
5.
bioRxiv ; 2023 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-36778338

RESUMO

Tendons are essential, frequently injured connective tissues that transmit forces from muscle to bone. Their unique highly ordered, matrix-rich structure is critical for proper function. While adult mammalian tendons heal after acute injuries, endogenous tendon cells, or tenocytes, fail to respond appropriately, resulting in the formation of disorganized fibrovascular scar tissue with impaired function and increased propensity for re-injury. Here, we show that unlike mammals, adult zebrafish tenocytes activate upon injury and fully regenerate the tendon. Using a full tear injury model in the adult zebrafish craniofacial tendon, we defined the hallmark stages and cellular basis of tendon regeneration through multiphoton imaging, lineage tracing, and transmission electron microscopy approaches. Remarkably, we observe that the zebrafish tendon can regenerate and restore normal collagen matrix ultrastructure by 6 months post-injury (mpi). We show that tendon regeneration progresses in three main phases: inflammation within 24 hours post-injury (hpi), cellular proliferation and formation of a cellular bridge between the severed tendon ends at 3-5 days post-injury (dpi), and re-differentiation and matrix remodeling beginning from 5 dpi to 6 mpi. Importantly, we demonstrate that pre-existing tenocytes are the main cellular source of regeneration. Collectively, our work debuts the zebrafish tendon as one of the only reported adult tendon regenerative models and positions it as an invaluable comparative system to identify regenerative mechanisms that may inspire new tendon injury treatments in the clinic.

6.
Development ; 150(3)2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36718794

RESUMO

The eighth EMBO conference in the series 'The Molecular and Cellular Basis of Regeneration and Tissue Repair' took place in Barcelona (Spain) in September 2022. A total of 173 researchers from across the globe shared their latest advances in deciphering the molecular and cellular basis of wound healing, tissue repair and regeneration, as well as their implications for future clinical applications. The conference showcased an ever-expanding diversity of model organisms used to identify mechanisms that promote regeneration. Over 25 species were discussed, ranging from invertebrates to humans. Here, we provide an overview of the exciting topics presented at the conference, highlighting novel discoveries in regeneration and perspectives for regenerative medicine.


Assuntos
Medicina Regenerativa , Cicatrização , Humanos , Espanha
7.
Clin Gastroenterol Hepatol ; 21(6): 1646-1648, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-35398568

RESUMO

One of the most common and devastating complications of alcohol use disorder (AUD) is the development of alcohol-associated liver disease (ALD).1 Unfortunately, outcomes of patients with ALD are poor, in large part because patients with ALD are diagnosed at a much later stage of disease compared with patients with other causes of liver disease.2 Accordingly, earlier detection is critical in combating the high mortality associated with ALD. In this work, we sought to assess the feasibility and impact of evaluating high-risk patients with no prior documented liver disease for the presence of advanced ALD while admitted to the hospital.


Assuntos
Alcoolismo , Hepatopatias Alcoólicas , Humanos , Alcoolismo/complicações , Alcoolismo/diagnóstico , Pacientes Internados , Hepatopatias Alcoólicas/complicações , Hepatopatias Alcoólicas/diagnóstico , Hepatopatias Alcoólicas/terapia , Consumo de Bebidas Alcoólicas/efeitos adversos
8.
Elife ; 112022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-36218256

RESUMO

Early events during axolotl limb regeneration include an immune response and the formation of a wound epithelium. These events are linked to a clearance of damaged tissue prior to blastema formation and regeneration of the missing structures. Here, we report the resorption of calcified skeletal tissue as an active, cell-driven, and highly regulated event. This process, carried out by osteoclasts, is essential for a successful integration of the newly formed skeleton. Indeed, the extent of resorption is directly correlated with the integration efficiency, and treatment with zoledronic acid resulted in osteoclast function inhibition and failed tissue integration. Moreover, we identified the wound epithelium as a regulator of skeletal resorption, likely releasing signals involved in recruitment/differentiation of osteoclasts. Finally, we reported a correlation between resorption and blastema formation, particularly, a coordination of resorption with cartilage condensation. In sum, our results identify resorption as a major event upon amputation, playing a critical role in the overall process of skeletal regeneration.


Assuntos
Ambystoma mexicanum , Osteoclastos , Animais , Ambystoma mexicanum/fisiologia , Ácido Zoledrônico , Extremidades/fisiologia , Esqueleto
9.
Dev Dyn ; 251(8): 1250-1266, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35338756

RESUMO

The classical anatomist Drew Noden spearheaded craniofacial research, laying the foundation for our modern molecular understanding of development, evolution, and disorders of the craniofacial skeleton. His work revealed the origin of cephalic musculature and the role of cranial neural crest (CNC) in early formation and patterning of the head musculoskeletal structures. Much of modern cranial tendon research advances a foundation of knowledge that Noden built using classical quail-chick transplantation experiments. This elegant avian chimeric system involves grafting of donor quail cells into host chick embryos to identify the cell types they can form and their interactions with the surrounding tissues. In this review, we will give a brief background of vertebrate head formation and the impact of CNC on the patterning, development, and evolution of the head musculoskeletal attachments. Using the zebrafish as a model system, we will discuss examples of modifications of craniofacial structures in evolution with a special focus on the role of tendon and ligaments. Lastly, we will discuss pathologies in craniofacial tendons and the importance of understanding the molecular and cellular dynamics during craniofacial tendon development in human disease.


Assuntos
Crista Neural , Peixe-Zebra , Animais , Embrião de Galinha , Humanos , Codorniz , Crânio , Tendões
10.
Blood ; 139(14): 2212-2226, 2022 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-35061876

RESUMO

Non-Hispanic Black (NHB) and Hispanic patients with acute myeloid leukemia (AML) have higher mortality rates than non-Hispanic White (NHW) patients despite more favorable genetics and younger age. A discrete survival analysis was performed on 822 adult patients with AML from 6 urban cancer centers and revealed inferior survival among NHB (hazard ratio [HR] = 1.59; 95% confidence interval [CI]: 1.15, 2.22) and Hispanic (HR = 1.25; 95% CI: 0.88, 1.79) patients compared with NHW patients. A multilevel analysis of disparities was then conducted to investigate the contribution of neighborhood measures of structural racism on racial/ethnic differences in survival. Census tract disadvantage and affluence scores were individually calculated. Mediation analysis of hazard of leukemia death between groups was examined across 6 composite variables: structural racism (census tract disadvantage, affluence, and segregation), tumor biology (European Leukemia Network risk and secondary leukemia), health care access (insurance and clinical trial enrollment), comorbidities, treatment patterns (induction intensity and transplant utilization), and intensive care unit (ICU) admission during induction chemotherapy. Strikingly, census tract measures accounted for nearly all of the NHB-NHW and Hispanic-NHW disparity in leukemia death. Treatment patterns, including induction intensity and allogeneic transplant, and treatment complications, as assessed by ICU admission during induction chemotherapy, were additional mediators of survival disparities in AML. This is the first study to formally test mediators for observed disparities in AML survival and highlights the need to investigate the mechanisms by which structural racism interacts with known prognostic and treatment factors to influence leukemia outcomes.


Assuntos
Leucemia Mieloide Aguda , Racismo Sistêmico , Adulto , Etnicidade , Disparidades nos Níveis de Saúde , Hispânico ou Latino , Humanos , Leucemia Mieloide Aguda/terapia , População Branca
11.
Am J Hosp Palliat Care ; 39(2): 220-227, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34000817

RESUMO

BACKGROUND: Healthcare providers increasingly care for patients with Limited English Proficiency (LEP). There is limited research evaluating healthcare provider utilization practices, attitudes, perceived benefits and barriers regarding the use of medical interpreters in end of life (EOL) and goals of care (GOC) conversations. OBJECTIVES: To elicit healthcare providers' opinions of the role, factors that impact decisions to use medical interpreters and perceived utility of using medical interpreters when conducting EOL and GOC conversations with LEP patients and their families. DESIGN: Cross-sectional survey of internal medicine trainees and attending physicians from a U.S. medical center. RESULTS: A total of 117 surveys were collected with a response rate of 51%. In-person medical interpreters received higher ratings with regard to their helpfulness compared to telephone medical interpreters during EOL and GOC conversations. Being an attending physician and having received training in the use of a medical interpreter predicted higher composite scores reflecting greater awareness of the roles of medical interpreters and endorsement of best communication practices. In-person interpreters were viewed by a subset of participants as "standard of care" during EOL and GOC conversations. CONCLUSION: Having more years in practice and receiving training in the use of medical interpreters correlated with more favorable attitudes toward the role of medical interpreters and positive communication practices. Incorporating early training in the use of medical interpreters could help enhance communication practices and outcomes during EOL and GOC conversations with LEP patients.


Assuntos
Proficiência Limitada em Inglês , Comunicação , Barreiras de Comunicação , Estudos Transversais , Morte , Pessoal de Saúde , Humanos , Relações Médico-Paciente , Tradução
12.
Nat Commun ; 12(1): 2595, 2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-33972536

RESUMO

Tissue regeneration is a process that recapitulates and restores organ structure and function. Although previous studies have demonstrated wound-induced hair neogenesis (WIHN) in laboratory mice (Mus), the regeneration is limited to the center of the wound unlike those observed in African spiny (Acomys) mice. Tissue mechanics have been implicated as an integral part of tissue morphogenesis. Here, we use the WIHN model to investigate the mechanical and molecular responses of laboratory and African spiny mice, and report these models demonstrate opposing trends in spatiotemporal morphogenetic field formation with association to wound stiffness landscapes. Transcriptome analysis and K14-Cre-Twist1 transgenic mice show the Twist1 pathway acts as a mediator for both epidermal-dermal interactions and a competence factor for periodic patterning, differing from those used in development. We propose a Turing model based on tissue stiffness that supports a two-scale tissue mechanics process: (1) establishing a morphogenetic field within the wound bed (mm scale) and (2) symmetry breaking of the epidermis and forming periodically arranged hair primordia within the morphogenetic field (µm scale). Thus, we delineate distinct chemo-mechanical events in building a Turing morphogenesis-competent field during WIHN of laboratory and African spiny mice and identify its evo-devo advantages with perspectives for regenerative medicine.


Assuntos
Epiderme/anatomia & histologia , Epiderme/metabolismo , Folículo Piloso/metabolismo , Morfogênese/fisiologia , Regeneração/fisiologia , Proteína 1 Relacionada a Twist/metabolismo , Cicatrização/fisiologia , Animais , Epiderme/fisiologia , Perfilação da Expressão Gênica , Folículo Piloso/anatomia & histologia , Folículo Piloso/fisiologia , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Análise em Microsséries , Microscopia de Força Atômica , Modelos Psicológicos , Morfogênese/genética , Murinae , RNA-Seq , Regeneração/genética , Medicina Regenerativa , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Análise Espaço-Temporal , Proteína 1 Relacionada a Twist/genética , Cicatrização/genética
13.
Oncologist ; 26(6): 483-491, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33586274

RESUMO

BACKGROUND: The National Comprehensive Cancer Network recommends either three cycles of bleomycin, etoposide, and cisplatin or four cycles of etoposide and cisplatin (EPx4) as initial chemotherapy for the treatment of good-risk germ cell tumors (GCTs). To assess the response, toxicity, and survival outcomes of EPx4, we analyzed our experience. MATERIAL AND METHODS: Response and survival outcomes, selected toxicities, and adherence to chemotherapy dose and schedule were assessed in patients with good-risk GCT who received EPx4 at Memorial Sloan Kettering Cancer Center between 1982 and 2016. The results were compared with our past results and published data. RESULTS: Between 1982 and 2016, 944 patients with GCT were treated with EPx4, 289 who were previously reported plus 655 treated between January 2000 and August 2016. A favorable response was achieved in 928 of 944 patients (98.3%). Five-year progression-free, disease-specific, and overall survival rates were 93.9%, 98.6%, and 97.9%, respectively. Median follow-up was 7.3 years (range, 2.8 months to 35.5 years). Viable, nonteratomatous malignant GCT was present in 3.5% of 432 postchemotherapy retroperitoneal lymph node dissection specimens from patients with nonseminomatous GCT. Febrile neutropenia and thromboembolic events occurred in 16.0% and 8.9%, respectively, with one treatment-related death. In the more recent 655-patient cohort, full-dose EPx4 was administered to 631 (96.3%), with deviations from planned treatment driven mainly by vascular (n = 13), hematologic (n = 11), renal (n = 7), or infectious (n = 5) events. CONCLUSION: EPx4 is highly effective and well tolerated in patients with good-risk GCTs and remains a standard of care. IMPLICATIONS FOR PRACTICE: Four cycles of etoposide and cisplatin (EPx4) is a standard-of-care regimen for all patients with good-risk germ cell tumors with a favorable response rate and disease-specific survival of 98%. Full-dose administration of etoposide and cisplatin and complete resection of residual disease lead to optimal outcomes. EPx4 should be the recommended regimen in active smokers, patients with reduced or borderline kidney function, and patients aged 50 years or older, which are patient groups at increased risk for bleomycin pulmonary toxicity. Because of a risk of acquired severe pulmonary illness, EPx4 may also be favored for patients who vape or use e-cigarettes and during ongoing transmission of severe acute respiratory syndrome coronavirus 2.


Assuntos
COVID-19 , Sistemas Eletrônicos de Liberação de Nicotina , Neoplasias Embrionárias de Células Germinativas , Neoplasias Testiculares , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Bleomicina/efeitos adversos , Cisplatino/efeitos adversos , Etoposídeo/efeitos adversos , Humanos , Masculino , Neoplasias Embrionárias de Células Germinativas/tratamento farmacológico , SARS-CoV-2 , Neoplasias Testiculares/tratamento farmacológico
14.
Dev Dyn ; 250(3): 393-413, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33169466

RESUMO

Tendons are specialized matrix-rich connective tissues that transmit forces from muscle to bone and are essential for movement. As tissues that frequently transfer large mechanical loads, tendons are commonly injured in patients of all ages. Following injury, mammalian tendons heal poorly through a slow process that forms disorganized fibrotic scar tissue with inferior biomechanical function. Current treatments are limited and patients can be left with a weaker tendon that is likely to rerupture and an increased chance of developing degenerative conditions. More effective, alternative treatments are needed. However, our current understanding of tendon biology remains limited. Here, we emphasize why expanding our knowledge of tendon development, healing, and regeneration is imperative for advancing tendon regenerative medicine. We provide a comprehensive review of the current mechanisms governing tendon development and healing and further highlight recent work in regenerative tendon models including the neonatal mouse and zebrafish. Importantly, we discuss how present and future discoveries can be applied to both augment current treatments and design novel strategies to treat tendon injuries.


Assuntos
Diferenciação Celular , Regeneração , Traumatismos dos Tendões/fisiopatologia , Traumatismos dos Tendões/terapia , Tendões/fisiologia , Animais , Humanos , Camundongos , Peixe-Zebra/embriologia
15.
J Vis Exp ; (160)2020 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-32658179

RESUMO

Classical experiments in salamander regenerative biology over the last century have long established that the wound epidermis is a crucial signaling structure that forms rapidly post-amputation and is required for limb regeneration. However, methods to study its precise function at the molecular level over the last decades have been limited due to a paucity of precise functional techniques and genomic information available in salamander model systems. Excitingly, the recent plethora of sequencing technologies coupled with the release of various salamander genomes and the advent of functional genetic testing methods, including CRISPR, makes it possible to re-visit these foundational experiments at unprecedented molecular resolution. Here, I describe how to perform the classically developed full skin flap (FSF) surgery in adult axolotls in order to inhibit wound epidermis formation immediately following amputation. The wound epidermis normally forms via distal migration of epithelial cells in the skin proximal to the amputation plane to seal off the wound from the outside environment. The surgery entails immediately suturing full thickness skin (which includes both epidermal and dermal layers) over the amputation plane to hinder epithelial cell migration and contact with the underlying damaged mesenchymal tissues. Successful surgeries result in the inhibition of blastema formation and limb regeneration. By combining this surgery method with contemporary downstream molecular and functional analyses, researchers can begin to uncover the molecular underpinnings of wound epidermis function and biology during limb regeneration.


Assuntos
Ambystoma mexicanum , Epiderme/fisiologia , Epiderme/cirurgia , Extremidades/fisiologia , Regeneração , Retalhos Cirúrgicos , Cicatrização , Amputação Cirúrgica , Animais , Movimento Celular , Transdução de Sinais
16.
Dev Cell ; 53(5): 561-576.e9, 2020 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-32516596

RESUMO

Regional specification is critical for skin development, regeneration, and evolution. The contribution of epigenetics in this process remains unknown. Here, using avian epidermis, we find two major strategies regulate ß-keratin gene clusters. (1) Over the body, macro-regional specificities (scales, feathers, claws, etc.) established by typical enhancers control five subclusters located within the epidermal differentiation complex on chromosome 25; (2) within a feather, micro-regional specificities are orchestrated by temporospatial chromatin looping of the feather ß-keratin gene cluster on chromosome 27. Analyses suggest a three-factor model for regional specification: competence factors (e.g., AP1) make chromatin accessible, regional specifiers (e.g., Zic1) target specific genome regions, and chromatin regulators (e.g., CTCF and SATBs) establish looping configurations. Gene perturbations disrupt morphogenesis and histo-differentiation. This chicken skin paradigm advances our understanding of how regulation of big gene clusters can set up a two-dimensional body surface map.


Assuntos
Proteínas Aviárias/metabolismo , Fator de Ligação a CCCTC/metabolismo , Montagem e Desmontagem da Cromatina , Células Epiteliais/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Morfogênese , beta-Queratinas/genética , Animais , Proteínas Aviárias/genética , Fator de Ligação a CCCTC/genética , Diferenciação Celular , Embrião de Galinha , Cromossomos/genética , Células Epiteliais/citologia , Plumas/citologia , Plumas/embriologia , Plumas/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/genética , Família Multigênica
17.
Elife ; 92020 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-32142407

RESUMO

How salamanders accomplish progenitor cell proliferation while faithfully maintaining genomic integrity and regenerative potential remains elusive. Here we found an innate DNA damage response mechanism that is evident during blastema proliferation (early- to late-bud) and studied its role during tissue regeneration by ablating the function of one of its components, Eyes absent 2. In eya2 mutant axolotls, we found that DNA damage signaling through the H2AX histone variant was deregulated, especially within the proliferating progenitors during limb regeneration. Ultimately, cell cycle progression was impaired at the G1/S and G2/M transitions and regeneration rate was reduced. Similar data were acquired using acute pharmacological inhibition of the Eya2 phosphatase activity and the DNA damage checkpoint kinases Chk1 and Chk2 in wild-type axolotls. Together, our data indicate that highly-regenerative animals employ a robust DNA damage response pathway which involves regulation of H2AX phosphorylation via Eya2 to facilitate proper cell cycle progression upon injury.


Assuntos
Ambystoma mexicanum/fisiologia , Extremidades/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Tirosina Fosfatases/metabolismo , Regeneração/fisiologia , Animais , Ciclo Celular/fisiologia , Dano ao DNA , Reparo do DNA/fisiologia , Regulação da Expressão Gênica , Histonas/genética , Histonas/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas Nucleares/genética , Proteínas Tirosina Fosfatases/genética
18.
J Clin Oncol ; 38(12): 1332-1337, 2020 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-32109195

RESUMO

PURPOSE: The relapse rate after primary retroperitoneal lymph node dissection (RPLND) for patients with pathologic stage (PS) IIA nonseminomatous germ cell tumors (NSGCTs) is 10%-20% but increases to ≥ 50% for PS IIB disease. We report our experience with 2 cycles of adjuvant etoposide plus cisplatin (EP×2) after therapeutic primary RPLND. PATIENTS AND METHODS: All patients with PS II NSGCT seen at Memorial Sloan Kettering Cancer Center from March 1989 to April 2016 and who were planned to receive EP×2 were included. Each cycle consisted of cisplatin 20 mg/m2 and etoposide 100 mg/m2 on days 1 through 5 at 21-day intervals. Demographic characteristics, histopathologic features, therapeutic and survival outcomes were recorded. RESULTS: Of 156 patients, 30 (19%) had pathologic N1, 122 (78%) had pathologic N2 (pN2), and 4 (3%) had pathologic N3 (pN3) disease. The median number of involved lymph nodes was 3 (range, 1-37 nodes), and the median size of the largest involved node was 2.0 cm (range, 0.4-7.0 cm); extranodal extension was present in 69 patients (45%). Embryonal carcinoma was the most frequent RPLND histology, present in 143 patients (92%). One hundred fifty patients (96%) received EP×2, five received EP×1 and one received EP×4. With a median follow-up of 9 years, 2 patients (1.3%; 1 patient each with pN2 and pN3 disease) experienced relapse; both patients remain continuously disease free at more than 5 and 22 years after salvage chemotherapy. Three patients died, all unrelated to NSGCT, yielding 10-year disease-specific, relapse-free, and overall survival rates of 100%, 98%, and 99%, respectively. CONCLUSION: Adjuvant EP×2 for PS II NSGCT is highly effective, has acceptable toxicity, and incurs less drug cost than 2 cycles of bleomycin, etoposide, and cisplatin. Inclusion of bleomycin in this setting is not necessary.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Embrionárias de Células Germinativas/tratamento farmacológico , Neoplasias Testiculares/tratamento farmacológico , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Quimioterapia Adjuvante , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Etoposídeo/administração & dosagem , Etoposídeo/efeitos adversos , Humanos , Excisão de Linfonodo , Linfonodos/patologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Neoplasias Embrionárias de Células Germinativas/patologia , Neoplasias Embrionárias de Células Germinativas/cirurgia , Neoplasias Testiculares/patologia , Neoplasias Testiculares/cirurgia , Adulto Jovem
19.
Elife ; 92020 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-31934849

RESUMO

Formation of a specialized wound epidermis is required to initiate salamander limb regeneration. Yet little is known about the roles of the early wound epidermis during the initiation of regeneration and the mechanisms governing its development into the apical epithelial cap (AEC), a signaling structure necessary for outgrowth and patterning of the regenerate. Here, we elucidate the functions of the early wound epidermis, and further reveal midkine (mk) as a dual regulator of both AEC development and inflammation during the initiation of axolotl limb regeneration. Through loss- and gain-of-function experiments, we demonstrate that mk acts as both a critical survival signal to control the expansion and function of the early wound epidermis and an anti-inflammatory cytokine to resolve early injury-induced inflammation. Altogether, these findings unveil one of the first identified regulators of AEC development and provide fundamental insights into early wound epidermis function, development, and the initiation of limb regeneration.


Assuntos
Ambystoma mexicanum/fisiologia , Inflamação/metabolismo , Midkina/metabolismo , Regeneração , Cicatrização , Animais , Proliferação de Células , Epiderme/metabolismo , Matriz Extracelular/metabolismo , Extremidades/fisiologia , Hibridização In Situ , Transdução de Sinais , Transcrição Gênica
20.
J Pain Symptom Manage ; 59(3): 694-701, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31669199

RESUMO

CONTEXT: Research has shown that using medical interpreters in language-discordant patient-provider encounters improves outcomes. There is limited research evaluating the views of medical interpreters on best interpreter practices when they are used to break bad news or participate in end-of-life (EOL) conversations. OBJECTIVES: To develop insights from medical interpreters about their role when interpreting discussions regarding EOL issues, identify practices interpreters perceive as helping to improve or hinder patient-provider communication, and obtain suggestions on how to improve communication during EOL conversations with Spanish-speaking and Chinese-speaking patients. METHODS: Semistructured interviews were conducted with Spanish or Chinese medical interpreters. Participants were recruited until thematic saturation was reached. Twelve interviews were conducted, audiotape recorded, transcribed, and analyzed using standard qualitative methods. RESULTS: Six major themes were identified: medical interpreters' perceived comfort level during EOL interpretation; perception of interpreter role; communication practices perceived as barriers to effective communication; communication practices felt to facilitate effective communication; concrete recommendations how to best use medical interpreters; and training received/perceived training needs. CONCLUSION: Medical interpreters provide literal interpretation of the spoken word. Because of cultural nuances in Chinese-speaking and Spanish-speaking patients/family members during EOL conversations, medical interpreters can translate the meaning of the message within a specific cultural context. Conducting premeetings and debriefings after the encounter are potentially important strategies to maximize communication during EOL conversations.


Assuntos
Barreiras de Comunicação , Idioma , China , Comunicação , Morte , Humanos , Relações Médico-Paciente , Tradução
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