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1.
Ecology ; 91(2): 448-59, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20392010

RESUMO

Black spruce (Picea mariana) is the most abundant tree species in the boreal biome, but little is known about how climate warming may change recruitment in peatlands, especially those affected by permafrost thaw. We used results from a seven-year study in northern Manitoba, Canada, to address the following questions: (1) What is the relative importance of early life history transitions on P. mariana recruitment? (2) How are these transitions mediated by biological and environmental factors, including competition, facilitation, disease, herbivory, water table depth, and soil nutrients? (3) Do interactions among these factors create additional recruitment limitations beyond those imposed by environmental factors changing with climate warming, such as hydrology? Seed rain was measured over six years on forested permafrost plateaus and in neighboring collapse scar bogs. Seed germination and seedling survival and growth were measured over 4-5 years in collapse scars and assessed across a three-level water table treatment. Survival and growth experiments examined additional combinations of above- and belowground vascular plant competition and fertilizer addition. Results showed that failure of germination and survival on growing moss surfaces and reduced survival of seedlings in wetter microsites were primary constraints. Seed influx was significantly lower in collapse scars but likely did not limit recruitment. Biological and environmental factors mediating these life history transitions also differed in relative importance, and interactions among them tended to amplify recruitment limitation. Seedling survival was most strongly controlled by fast-growing mosses in wet microsites but also was influenced by apparent drowning in wet plots, herbivory, and loss of foliage caused by a fungal pathogen. Seedling growth was strongly controlled by water table depth, nutrient and competition levels, and fungal pathogens. Multiple, interacting factors will affect P. mariana establishment in boreal peatlands during climate warming. Generalizations about recruitment relying on few environmental gradients sensitive to climate change, such as water table, may therefore not fully capture the complexities of establishment.


Assuntos
Picea/fisiologia , Regiões Árticas , Mudança Climática , Ecossistema , Meio Ambiente , Fertilizantes , Congelamento , Doenças das Plantas/microbiologia , Plântula/fisiologia , Solo , Fatores de Tempo , Água
2.
Ther Adv Med Oncol ; 12: 1758835920967259, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33299473

RESUMO

BACKGROUND: Stomatitis is a frequent dose limiting toxicity of everolimus, an approved therapy for patients with metastatic breast cancer. No randomized trials of a prophylactic measure to prevent mucositis have been reported. METHODS: We conducted a phase II, open-label trial in which patients with metastatic breast cancer starting everolimus were randomized to best supportive care (BSC) versus prophylactic use of an oral mucoadhesive, non-steroid containing mouth wash. The primary endpoint was rate of any grade stomatitis as reported by the treating physicians. Secondary endpoints were severity of stomatitis according to the Oral Mucositis Assessment Scale (OMAS) and rates of everolimus dose reduction or discontinuation due to mucositis. RESULTS: Of 61 evaluable patients, 32 were randomized to and treated with oral mucoadhesive and 29 with BSC. Any grade stomatitis developed in 46.9% (15/32) of study arm and 65.5% (19/29) of BSC arm patients (p = 0.14). The difference between the two arms was significantly in favor of the mucoadhesive arm when mucositis was scored according to the OMAS with average score of 0.3 in study arm versus 0.5 in the control arm (p = 0.03). There were fewer dose adjustments or therapy discontinuations in the study arm compared with BSC (16% versus 31%, respectively) but the difference did not reach statistical significance. CONCLUSION: Here we provide early evidence from the first randomized trial supporting the use of oral prophylactic mucoadhesive for everolimus-associated stomatitis. A trial comparing prophylactic oral mucoadhesive to steroid mouth wash may be warranted.

3.
Nat Commun ; 11(1): 5824, 2020 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-33203854

RESUMO

In this multicenter, open-label, randomized phase II investigator-sponsored neoadjuvant trial with funding provided by Sanofi and GlaxoSmithKline (TRIO-US B07, Clinical Trials NCT00769470), participants with early-stage HER2-positive breast cancer (N = 128) were recruited from 13 United States oncology centers throughout the Translational Research in Oncology network. Participants were randomized to receive trastuzumab (T; N = 34), lapatinib (L; N = 36), or both (TL; N = 58) as HER2-targeted therapy, with each participant given one cycle of this designated anti-HER2 therapy alone followed by six cycles of standard combination chemotherapy with the same anti-HER2 therapy. The primary objective was to estimate the rate of pathologic complete response (pCR) at the time of surgery in each of the three arms. In the intent-to-treat population, we observed similar pCR rates between T (47%, 95% confidence interval [CI] 30-65%) and TL (52%, 95% CI 38-65%), and a lower pCR rate with L (25%, 95% CI 13-43%). In the T arm, 100% of participants completed all protocol-specified treatment prior to surgery, as compared to 69% in the L arm and 74% in the TL arm. Tumor or tumor bed tissue was collected whenever possible pre-treatment (N = 110), after one cycle of HER2-targeted therapy alone (N = 89), and at time of surgery (N = 59). Higher-level amplification of HER2 and hormone receptor (HR)-negative status were associated with a higher pCR rate. Large shifts in the tumor, immune, and stromal gene expression occurred after one cycle of HER2-targeted therapy. In contrast to pCR rates, the L-containing arms exhibited greater proliferation reduction than T at this timepoint. Immune expression signatures increased in all arms after one cycle of HER2-targeted therapy, decreasing again by the time of surgery. Our results inform approaches to early assessment of sensitivity to anti-HER2 therapy and shed light on the role of the immune microenvironment in response to HER2-targeted agents.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Microambiente Tumoral/efeitos dos fármacos , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/cirurgia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Lapatinib/administração & dosagem , Lapatinib/uso terapêutico , Pessoa de Meia-Idade , Terapia de Alvo Molecular/métodos , Terapia Neoadjuvante , Receptor ErbB-2/antagonistas & inibidores , Receptor ErbB-2/metabolismo , Trastuzumab/administração & dosagem , Trastuzumab/uso terapêutico , Resultado do Tratamento , Microambiente Tumoral/genética
4.
Lung Cancer ; 135: 104-109, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31446981

RESUMO

BACKGROUND: Luminespib (AUY922) is a second-generation heat shock protein 90 (HSP90) inhibitor with demonstrated activity in non-small cell lung cancer (NSCLC). Since luminespib reduces levels of dihydrofolate reductase (DHFR), a key enzymatic target of pemetrexed, we assessed the safety and tolerability of luminespib in combination with pemetrexed in patients with previously treated metastatic non-squamous non-small cell lung cancer (NSCLC). We also sought to study the pharmacokinetics and correlate tumor dihydrofolate reductase (DHFR) expression with clinical response. METHODS: Patients received weekly luminespib at either 40 mg/m2, 55 mg/m2, or 70 mg/m2 according to a standard 3 + 3 dose-escalation design along with pemetrexed at 500 mg/m2 followed by an expansion at the maximum tolerated dose (MTD). RESULTS: Two-dose limiting toxicities (DLTs) were experienced in the 70 mg/m2 cohort, therefore the MTD was determined to be 55 mg/m2. 69% (N = 9) of patients experienced ophthalmologic toxicity related to luminespib. Maximum serum concentration (Cmax) of luminespib was associated with increased grade 2 drug related adverse events (DRAEs) (rs = 0.74, P < 0.01), with volume of distribution (VD) inversely associated with the number of DRAEs (rs = - 0.81, P = 0.004) and ophthalmologic related DRAEs (rs = - 0.65, P = 0.04). The best response was partial response in one patient for 20 months, prior to expiration of all luminespib. Amongst patients treated at the MTD, the objective response rate was 14%. CONCLUSION: In patients with previously treated metastatic NSCLC, the MTD of luminespib in combination with pemetrexed was 55 mg/m2 per week. The combination of luminespib and pemetrexed demonstrated clinical activity. Tolerability of luminespib with pemetrexed is limited by ocular toxicity.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Biomarcadores Tumorais , Carcinoma Pulmonar de Células não Pequenas/patologia , Feminino , Humanos , Isoxazóis/administração & dosagem , Isoxazóis/efeitos adversos , Isoxazóis/farmacocinética , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Estadiamento de Neoplasias , Pemetrexede/administração & dosagem , Pemetrexede/efeitos adversos , Pemetrexede/farmacocinética , Resorcinóis/administração & dosagem , Resorcinóis/efeitos adversos , Resorcinóis/farmacocinética , Resultado do Tratamento
5.
Ther Adv Med Oncol ; 10: 1758835918807339, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30542377

RESUMO

BACKGROUND: Improving outcomes for patients with human epidermal growth factor 2-positive (HER2+) central nervous system (CNS) metastases remains an unmet clinical need. This trial evaluated a novel combination of everolimus, lapatinib and capecitabine for this disease. METHODS: Patients with trastuzumab-pretreated, HER2+ breast cancer brain metastasis without prior therapy with a mammalian target of rapamycin (mTOR) inhibitor were eligible. Patients received lapatinib and everolimus daily (continuously) and capecitabine twice daily (d1-14) in 21-d cycles. The primary endpoint was the 12-week CNS objective response rate (ORR). Secondary endpoints included safety, progression-free survival (PFS), overall survival (OS), best CNS ORR and extra-CNS ORR. RESULTS: A total of 19 participants were enrolled and treated with ⩾1 dose of the study drug. The median age was 58.5 years, the median number of therapies for metastatic breast cancer was 2.5 (0-11). Pretrial, 74% of participants had received prior lapatinib, capecitabine or both. A total of 63% had received previous CNS radiation or surgical resection and CNS radiation. The maximum tolerated doses were lapatinib at 1000 mg, everolimus at 10 mg, and capecitabine at 1000 mg/m2. Phase II proceeded with capecitabine at 750 mg/m2 due to better tolerability. The most common grade 3/4 adverse events were mucositis (16%), diarrhea, fatigue, and hypokalemia (11% each). Of 11 participants evaluable for 12-week CNS ORR, 3 (27%) had partial response and 7 (64%) had stable disease. The best CNS ORR in eligible participants was 28% (5/18). The median PFS and OS were 6.2 and 24.2 months, respectively. CONCLUSIONS: This novel triplet combination of lapatinib, everolimus, and capecitabine is well tolerated and yielded a 27% response rate in the CNS at 12 weeks in heavily pretreated participants. Larger studies are warranted to further evaluate this regimen. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01783756. Registered 05 February 2013, https://clinicaltrials.gov/ct2/show/NCT01783756.

6.
Lung Cancer ; 123: 91-98, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30089602

RESUMO

OBJECTIVES: This open-label, randomized phase II trial evaluated antitumor efficacy of an antiestrogen, fulvestrant, in combination with human epidermal growth factor receptor (EGFR) inhibitor, erlotinib, in advanced non-small cell lung cancer (NSCLC) patients. MATERIALS AND METHODS: Patients with advanced or metastatic NSCLC, ECOG 0-2, previous chemotherapy unless patient refusal, and no prior EGFR-directed therapy were randomized 2:1 to erlotinib 150 mg oral daily plus 500 mg intramuscular fulvestrant on day 1, 15, 29 and every 28 days thereafter or erlotinib alone 150 mg oral daily. The primary end point was objective response rate (ORR); secondary endpoints included progression free survival (PFS) and overall survival (OS). RESULTS: Among 106 randomized patients, 100 received at least one dose of study drug. ORR was 16.4% (11 of 67 patients) for the combination versus 12.1% (4 of 33 patients) for erlotinib (p = 0.77). PFS median 3.5 versus 1.9 months [HR = 0.86, 95% CI (0.52-1.43), p = 0.29] and OS median 9.5 versus 5.8 months [HR = 0.92, 95% CI (0.57-1.48), p = 0.74] numerically favored the combination. In an unplanned subset analysis, among EGFR wild type patients (n = 51), but not EGFR mutant patients (n = 17), median PFS was 3.5 versus 1.7 months [HR = 0.35, 95% CI (0.14-0.86), p = 0.02] and OS was 6.2 versus 5.2 months [HR = 0.72, 95% CI (0.35-1.48), p = 0.37] for combined therapy versus erlotinib, respectively. Notably, EGFR WT patients were more likely to be hormone receptor-positive (either estrogen receptor α- and/or progesterone receptor-positive) compared to EGFR mutant patients (50% versus 9.1%, respectively) (p = 0.03). Treatment was well tolerated with predominant grade 1-2 dermatologic and gastrointestinal adverse effects. CONCLUSION: Addition of fulvestrant to erlotinib was well tolerated, with increased activity noted among EGFR wild type patients compared to erlotinib alone, albeit in an unplanned subset analysis.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Cloridrato de Erlotinib/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Biomarcadores Tumorais , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Cloridrato de Erlotinib/administração & dosagem , Feminino , Fulvestranto/administração & dosagem , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Análise de Sobrevida , Resultado do Tratamento
8.
Health Hum Rights ; 13(2): E3-16, 2011 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-22773030

RESUMO

BACKGROUND: Human trafficking has been recognized both by the international community and many individual states around the world as a serious violation of human rights. Trafficking is associated with extreme violence and a range of physical, mental, and sexual health consequences. Despite the extreme nature of the harm caused by human trafficking, harm is not a concept that is integrated in the definition of trafficking or in policies to address the health of trafficked people. This paper examines the United Kingdom's response to human trafficking as a case study to explore national policy responses to the health needs of trafficked people and assess the willingness of UK authorities to implement international and regional law in securing trafficked people's health rights. METHODS: Between 2007 and 2010, data on the development of the UK response to trafficking were obtained through 46 interviews with key trafficking policy stakeholders and health care providers, participant observation at 41 policy-relevant events, and document collection. Framework analysis was used to analyze the data. RESULTS: International and regional instruments specifically protect the health rights of trafficked people. Yet, UK engagement with trafficked people's health rights has been limited to granting, under certain circumstances, free access to health care services. Changes to trafficked people's entitlements to free health care occurred following the ratification of the Council of Europe Convention on Action Against Trafficking in Human Beings, but had limited impact on trafficked people's access to medical care. CONCLUSIONS: International and regional instruments that provide specific or mandated instruction about states' health care obligations can be effective in furthering the health rights of vulnerable migrant groups. The UK government has demonstrated limited appetite for exceeding its minimum obligations to provide for the health of trafficked people, however, and key principles for promoting the health rights of trafficked people are yet to be fulfilled.


Assuntos
Crime , Acessibilidade aos Serviços de Saúde/legislação & jurisprudência , Direitos Humanos , Internacionalidade , Formulação de Políticas , Humanos , Problemas Sociais , Reino Unido , Violência
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