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BACKGROUND: We evaluated whether tissue tumor mutational burden (tTMB) and STK11, KEAP1, and KRAS mutations have clinical utility as biomarkers for pembrolizumab monotherapy versus platinum-based chemotherapy in patients with programmed death ligand 1 (PD-L1)-positive (tumor proportion score ≥1%) advanced/metastatic non-small-cell lung cancer (NSCLC) without EGFR/ALK alterations in the phase III KEYNOTE-042 trial. PATIENTS AND METHODS: This retrospective exploratory analysis assessed prevalence of tTMB and STK11, KEAP1, and KRAS mutations determined by whole-exome sequencing of tumor tissue and matched normal DNA and their associations with outcomes in KEYNOTE-042. Clinical utility of tTMB was assessed using a prespecified cut point of 175 mutations/exome. RESULTS: Of 793 patients, 345 (43.5%) had tTMB ≥175 mutations/exome and 448 (56.5%) had tTMB <175 mutations/exome. No association was observed between PD-L1 expression and tTMB. Continuous tTMB score was associated with improved overall survival (OS) and progression-free survival among patients receiving pembrolizumab (Wald test, one-sided P < 0.001) but not those receiving chemotherapy (Wald test, two-sided P > 0.05). tTMB ≥175 mutations/exome was associated with improved outcomes for pembrolizumab versus chemotherapy, whereas tTMB <175 mutations/exome was not {OS: hazard ratio, 0.62 [95% confidence interval (CI) 0.48-0.80] and 1.09 (95% CI 0.88-1.36); progression-free survival: 0.75 (0.59-0.95) and 1.27 (1.04-1.55), respectively}. Improved OS [hazard ratio (95% CI)] for pembrolizumab versus chemotherapy was observed regardless of STK11 [STK11 mutant (n = 33): 0.37 (0.16-0.86), STK11 wild-type (n = 396): 0.83 (0.65-1.05)]; KEAP1 [KEAP1 mutant (n = 64): 0.75 (0.42-1.35), KEAP1 wild-type (n = 365): 0.78 (0.61-0.99)], or KRAS [KRAS mutant (n = 69): 0.42 (0.22-0.81); KRAS wild-type (n = 232): 0.86 (0.63-1.18)] mutation status. CONCLUSION: tTMB with a cut point of ≥175 mutations/exome is a potential predictive biomarker for pembrolizumab monotherapy for advanced/metastatic PD-L1 tumor proportion score ≥1% NSCLC. Pembrolizumab is a standard first-line treatment in this setting regardless of STK11, KEAP1, or KRAS mutation status.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Antígeno B7-H1/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Estudos Retrospectivos , Proteínas Proto-Oncogênicas p21(ras)/genética , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/uso terapêutico , Mutação , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêuticoRESUMO
The relative abundance of cosmic ray nickel nuclei with respect to iron is by far larger than for all other transiron elements; therefore it provides a favorable opportunity for a low background measurement of its spectrum. Since nickel, as well as iron, is one of the most stable nuclei, the nickel energy spectrum and its relative abundance with respect to iron provide important information to estimate the abundances at the cosmic ray source and to model the Galactic propagation of heavy nuclei. However, only a few direct measurements of cosmic-ray nickel at energy larger than â¼3 GeV/n are available at present in the literature, and they are affected by strong limitations in both energy reach and statistics. In this Letter, we present a measurement of the differential energy spectrum of nickel in the energy range from 8.8 to 240 GeV/n, carried out with unprecedented precision by the Calorimetric Electron Telescope (CALET) in operation on the International Space Station since 2015. The CALET instrument can identify individual nuclear species via a measurement of their electric charge with a dynamic range extending far beyond iron (up to atomic number Z=40). The particle's energy is measured by a homogeneous calorimeter (1.2 proton interaction lengths, 27 radiation lengths) preceded by a thin imaging section (3 radiation lengths) providing tracking and energy sampling. This Letter follows our previous measurement of the iron spectrum [1O. Adriani et al. (CALET Collaboration), Phys. Rev. Lett. 126, 241101 (2021).PRLTAO0031-900710.1103/PhysRevLett.126.241101], and it extends our investigation on the energy dependence of the spectral index of heavy elements. It reports the analysis of nickel data collected from November 2015 to May 2021 and a detailed assessment of the systematic uncertainties. In the region from 20 to 240 GeV/n our present data are compatible within the errors with a single power law with spectral index -2.51±0.07.
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Neoplasias do Colo , Laparoscopia , Mesocolo , Colectomia , Neoplasias do Colo/cirurgia , Humanos , Excisão de Linfonodo , Mesocolo/cirurgiaRESUMO
The Calorimetric Electron Telescope (CALET), in operation on the International Space Station since 2015, collected a large sample of cosmic-ray iron over a wide energy interval. In this Letter a measurement of the iron spectrum is presented in the range of kinetic energy per nucleon from 10 GeV/n to 2.0 TeV/n allowing the inclusion of iron in the list of elements studied with unprecedented precision by space-borne instruments. The measurement is based on observations carried out from January 2016 to May 2020. The CALET instrument can identify individual nuclear species via a measurement of their electric charge with a dynamic range extending far beyond iron (up to atomic number Z=40). The energy is measured by a homogeneous calorimeter with a total equivalent thickness of 1.2 proton interaction lengths preceded by a thin (3 radiation lengths) imaging section providing tracking and energy sampling. The analysis of the data and the detailed assessment of systematic uncertainties are described and results are compared with the findings of previous experiments. The observed differential spectrum is consistent within the errors with previous experiments. In the region from 50 GeV/n to 2 TeV/n our present data are compatible with a single power law with spectral index -2.60±0.03.
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Colo Transverso , Neoplasias do Colo , Laparoscopia , Mesocolo , Colectomia , Colo Transverso/diagnóstico por imagem , Colo Transverso/cirurgia , Neoplasias do Colo/diagnóstico por imagem , Neoplasias do Colo/cirurgia , Humanos , Ligadura , Excisão de Linfonodo , Mesocolo/cirurgia , Resultado do TratamentoRESUMO
[This corrects the article DOI: 10.1186/s40902-017-0107-3.].
RESUMO
BACKGROUND: Because of changing surgical procedures in the fields of oral and maxillofacial surgery, new methods for surgical education are needed and could include recent advances in digital technology. Many doctors have attempted to use digital technology as educational tools for surgical training, and movies have played an important role in these attempts. We have been using a 3D full high-definition (full-HD) camcorder to record movies of intra-oral surgeries. METHOD: The subjects were medical students and doctors receiving surgical training who did not have actual surgical experience (n = 67). Participants watched an 8-min, 2D movie of orthognathic surgery and subsequently watched the 3D version. After watching the 3D movie, participants were asked to complete a questionnaire. RESULT: A lot of participants (84%) felt a 3D movie excellent or good and answered that the advantages of a 3D movie were their appearance of solidity or realism. Almost all participants (99%) answered that 3D movies were quite useful or useful for medical practice. CONCLUSIONS: Three-dimensional full-HD movies have the potential to improve the quality of medical education and clinical practice in oral and maxillofacial surgery.
Assuntos
Bronquiolite Obliterante/tratamento farmacológico , Transplante de Células-Tronco Hematopoéticas , Mesilato de Imatinib/administração & dosagem , Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , Adulto , Aloenxertos , Bronquiolite Obliterante/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND: Currently, no effective treatments exist for non-small cell lung cancer (NSCLC) after failure of gefitinib therapy. Pre-clinical studies have demonstrated that gefitinib-resistant NSCLC cells are more sensitive to irinotecan than parental cells, and that combined administration of irinotecan and gefitinib has a synergistic additive effect. We conducted a phase I study to evaluate the combination of irinotecan and gefitinib as a therapeutic option for NSCLC patients with progressive disease (PD) after initial gefitinib treatment. METHODS: Eligibility criteria included histologically confirmed NSCLC, age range of 20-74 years, refractory to or relapsed after gefitinib treatment, one or more previous chemotherapy regimens, Eastern Cooperative Oncology Group performance status 0-2, adequate organ function, and informed consent. Patients were treated with irinotecan on days 1 and 15, and treated daily with gefitinib from day 2 every 4 weeks. The treatment was continued until disease progression. The gefitinib dose was fixed at 250 mg. Irinotecan dosing started at 50 mg m(-2) and was escalated in patients by 25 mg m(-2) increments up to a maximum dose of 150 mg m(-2). RESULTS: Twenty-seven patients were enrolled: male/female=14/13; median age=60 (45-75); histology, adenocarcinoma/non-adenocarcinoma=25/2; performance status 0-1/2=19/8; previous response to gefitinib, partial response/stable disease/PD=21/2/4. Dose-limiting toxicities were observed in 2 patients at level 3. Maximum tolerated dose was not determined, and the full dose of irinotecan could be combined with the full dose of gefitinib. The disease control rate (DCR) and response rate (RR) were 69.2 and 26.9%, respectively. For 12 patients at level 5 (the recommended phase II dose), the DCR and RR were 75.0% and 41.7%, respectively. The median treatment cycles were 4; median time to treatment failure, 57 days (95% confidence interval (CI), 32-82 days); median overall survival, 244 days (95% CI, 185-303 days); and 1-year survival rate, 32.6%. CONCLUSION: The combination of irinotecan and gefitinib was well tolerated and potentially beneficial for NSCLC patients failing initial gefitinib monotherapy.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Camptotecina/administração & dosagem , Camptotecina/análogos & derivados , Receptores ErbB/genética , Feminino , Gefitinibe , Humanos , Irinotecano , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Mutação , Quinazolinas/administração & dosagem , Resultado do TratamentoAssuntos
Valva Aórtica/diagnóstico por imagem , Fibroma/diagnóstico , Neoplasias Cardíacas/diagnóstico , Doenças das Valvas Cardíacas/diagnóstico , Idoso , Ecocardiografia Transesofagiana , Feminino , Fibroma/patologia , Neoplasias Cardíacas/patologia , Doenças das Valvas Cardíacas/patologia , HumanosRESUMO
The aim of this study was to evaluate the usefulness of EGFR mutation status in serum DNA as a means of predicting a benefit from gefitinib (IRESSA) therapy in Japanese patients with non-small cell lung cancer (NSCLC). We obtained pairs of tumour and serum samples from 42 patients treated with gefitinib. EGFR mutation status was determined by a direct sequencing method and by Scorpion Amplification Refractory Mutation System (ARMS) technology. EGFR mutations were detected in the tumour samples of eight patients and in the serum samples of seven patients. EGFR mutation status in the tumours and serum samples was consistent in 39 (92.9%) of the 42 pairs. EGFR mutations were strong correlations between both EGFR mutation status in the tumour samples and serum samples and objective response to gefitinib (P<0.001). Median progression-free survival time was significantly longer in the patients with EGFR mutations than in the patients without EGFR mutations (194 vs 55 days, P=0.016, in tumour samples; 174 vs 58 days, P=0.044, in serum samples). The results suggest that it is feasible to use serum DNA to detect EGFR mutation, and that it's potential as a predictor of response to, and survival on gefitinib is worthy of further evaluation.
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Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Receptores ErbB/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutação , Quinazolinas/farmacologia , Adulto , Idoso , Antineoplásicos/uso terapêutico , Povo Asiático/genética , Carcinoma Pulmonar de Células não Pequenas/mortalidade , DNA de Neoplasias/análise , DNA de Neoplasias/isolamento & purificação , Intervalo Livre de Doença , Feminino , Gefitinibe , Humanos , Japão , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Inibidores de Proteínas Quinases/farmacologia , Quinazolinas/uso terapêutico , Sensibilidade e EspecificidadeRESUMO
Epidermal growth factor receptor (EGFR) mutations are strong determinants of tumour response to EGFR tyrosine kinase inhibitors in non-small-cell lung cancer (NSCLC). Pleural effusion is a common complication of lung cancer. In this study, we assessed the feasibility of detection of EGFR mutations in samples of pleural effusion fluid. We obtained 43 samples, which was the cell-free supernatant of pleural fluid, from Japanese NSCLC patients, and examined them for EGFR mutations. The epidermal growth factor receptor mutation status was determined by a direct sequencing method (exons 18-21 in EGFR). EGFR mutations were detected in 11 cases (E746_A750del in seven cases, E746_T751del insA in one case, L747_T751del in one case, and L858R in two cases). The EGFR mutations were observed more frequently in women and non-smokers. A comparison between the EGFR mutant status and the response to gefitinib in the 27 patients who received gefitinib revealed that all seven patients with partial response and one of the seven patients with stable disease had an EGFR mutation. No EGFR mutations were detected in the patients with progressive disease. The results suggest that DNA in pleural effusion fluid can be used to detect EGFR mutations and that the EGFR mutation status may be useful as a predictor of the response to gefitinib.
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Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/genética , Receptores ErbB/genética , Neoplasias Pulmonares/genética , Mutação/genética , Derrame Pleural Maligno/genética , Quinazolinas/uso terapêutico , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Adulto , Idoso , Carcinoma de Células Grandes/tratamento farmacológico , Carcinoma de Células Grandes/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/genética , Análise Mutacional de DNA , DNA de Neoplasias/análise , DNA de Neoplasias/genética , Receptores ErbB/antagonistas & inibidores , Estudos de Viabilidade , Feminino , Gefitinibe , Testes Genéticos , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prognóstico , Sensibilidade e Especificidade , Resultado do TratamentoRESUMO
BACKGROUND: Adhesion molecules such as intercellular adhesion molecule-1 (ICAM-1) are thought to contribute to the airway inflammation and airway hyper-responsiveness (AHR) of allergic asthma. Some differences from allergic asthma have been noted, including airway neutrophilia, and the involvement of ICAM-1 in toluene diisocyanate (TDI) asthma is currently unclear. OBJECTIVE: We utilized mice lacking ICAM-1 expression (ICAM-1(-/-)) to investigate the role of ICAM-1 in airway inflammation and AHR in TDI-induced asthma. METHODS: Male C57BL/6J mice (ICAM-1(+/+)) and ICAM-1(-/-) mice were intranasally sensitized to TDI solution or solvent alone. Airway inflammation, AHR and cytokine secretion were assessed 24 h after challenge by TDI or solvent. The production of antigen-specific IgG and IgE by TDI sensitized and non-sensitized mice was determined. RESULTS: TDI challenge to ICAM-1(+/+) mice induced an increase in airway inflammatory cell numbers, AHR and cytokine secretion of TNF-alpha, macrophage inflammatory protein-2 (MIP-2), IL-4, IL-5 and IFN-gamma into the bronchoalveolar lavage fluid. All these pathophysiological changes were reduced in ICAM-1(-/-) mice. Serum levels of TDI-specific IgG and IgE of ICAM-1(-/-) and ICAM-1(+/+) mice were comparable. CONCLUSION: These results suggest that ICAM-1 plays an essential role in airway inflammation and AHR in TDI-induced asthma.
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Asma/induzido quimicamente , Molécula 1 de Adesão Intercelular/fisiologia , Doenças Profissionais/etiologia , Tolueno 2,4-Di-Isocianato/efeitos adversos , Animais , Asma/imunologia , Asma/metabolismo , Hiper-Reatividade Brônquica , Testes de Provocação Brônquica , Líquido da Lavagem Broncoalveolar/imunologia , Broncoconstritores , Quimiocina CXCL2 , Quimiocinas/imunologia , Imunoglobulina E/sangue , Imunoglobulina G/sangue , Imuno-Histoquímica/métodos , Molécula 1 de Adesão Intercelular/análise , Molécula 1 de Adesão Intercelular/genética , Interferon gama/imunologia , Interleucina-4/imunologia , Interleucina-5/imunologia , Pulmão/química , Pulmão/imunologia , Pulmão/metabolismo , Masculino , Cloreto de Metacolina , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Animais , Doenças Profissionais/imunologia , Doenças Profissionais/metabolismo , Fatores de Tempo , Fator de Necrose Tumoral alfa/imunologiaRESUMO
The aim of this study was to analyze the iodine-unstained region expanding around oral squamous cell carcinoma (SCC) by quantification of telomerase activity. The epithelial dysplasia often observed around SCC is considered to cause local recurrence or a second primary cancer. However these areas are hard to distinguish from normal mucosa. To clear the border of the expanding epithelial dysplasia around SCC, we stained with 3% iodine solution, and then decided the surgical margin. We measured quantification of telomerase activity in tumor, in epithelial dysplasia, and also in normal epithelium. Thirty-three primary cases of oral SCC which have iodine-unstained region around lesions were investigated. Fluorescense-based TRAP was applied to obtain quantification of telomerase activity. We obtained the following results: histological examination confirmed that every patient's unstained region consisted of various degrees of epithelial dysplasia. The quantified telomerase activities for squamous cell carcinoma, epithelial dysplasia and normal epithelium were 53.9, 39.6 and 2.7 U/microgP, respectively, and there was a significant difference between carcinoma and normal areas, and between dysplasia and normal epithelium. Therefore, these findings suggest that the areas of epithelial dysplasia unstained by iodine consist of cells that are nearly cancerous and excessively proliferative, and that epithelial dysplasia around SCC should be resected together with the tumor. Vital staining with iodine is useful for identifying epithelial dysplasia around SCC.
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Biomarcadores Tumorais/análise , Carcinoma de Células Escamosas/enzimologia , Neoplasias Bucais/enzimologia , Lesões Pré-Cancerosas/enzimologia , Telomerase/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/patologia , Epitélio/enzimologia , Epitélio/patologia , Feminino , Humanos , Iodo , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/enzimologia , Mucosa Bucal/patologia , Neoplasias Bucais/patologia , Lesões Pré-Cancerosas/patologia , Coloração e RotulagemRESUMO
Recent advances in off-pump coronary artery bypass (OPCAB) technique have demonstrated that multivessel coronary revascularization can be safely performed in selected patient without cardiopulmonary bypass. Numerous positioning technique and devices have been developed to assist access to coronary vessels during OPCAB, such as deep pericardial suture, surgical pads, and cardiac positioning device and stabilizers. We used new cardiac positioning device Starfish heart positioner (Medtronic Corporation) for 2 case of OPCAB. Starfish heart positioner was very useful to successfully perform multivessel coronary bypass on all walls of the beating heart. Starfish heart positioner will facilitate and expand the ability to easily and consistently perform OPCAB.
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Procedimentos Cirúrgicos Cardíacos/instrumentação , Ponte de Artéria Coronária/métodos , Estenose Coronária/cirurgia , Idoso , Anastomose Cirúrgica/métodos , Procedimentos Cirúrgicos Cardíacos/normas , Aneurisma Coronário/cirurgia , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND: The epithelial reticular basement membrane (Rbm) of the airway wall thickens in patients with asthma. However, whether the thickening parallels whole airway wall thickening, which limits airflow, is unknown. The aim of this study was to examine the correlation between the bronchial Rbm thickening and whole airway wall thickening in asthma. In addition, the association of Rbm and whole wall thickening with airflow obstruction was examined. METHODS: Forty nine patients with asthma and 18 healthy control subjects took part in the study. The Rbm thickness was measured in bronchial biopsy specimens and whole airway wall thickness was assessed with high resolution computed tomographic (HRCT) scanning after pretreatment with oral steroids for 2 weeks and inhaled beta2 agonist to minimise reversible changes of the airway walls. The percentage airway wall area (WA%; defined as (wall area/total airway area) x 100) and percentage airway wall thickness (WT%; defined as [(ideal outer diameter - ideal luminal diameter)/ideal outer diameter] x 100) were determined from HRCT scans to assess whole airway wall thickness. Spirometric tests were also performed. RESULTS: WA% and WT% were higher in patients with asthma than in healthy subjects. Both WA% and WT% were strongly correlated with Rbm thickness. Moreover, these three indices of airway wall thickness were inversely correlated with the percentage of predicted forced expiratory volume in 1 second in patients with asthma. CONCLUSIONS: These findings indicate that Rbm thickening parallels whole airway wall thickening which can cause irreversible airflow obstruction in patients with asthma.
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Asma/patologia , Brônquios/patologia , Asma/fisiopatologia , Biópsia/métodos , Estudos de Casos e Controles , Feminino , Volume Expiratório Forçado/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X/métodosRESUMO
Odontogenic ghost cell tumour (OGCT), also referred to as dentinogenic ghost cell tumour, is an extremely rare tumour classified as a neoplastic variant of calcifying ondontogenic cyst (COC). To date, only 13 cases of OGCT arising in the maxilla or mandible have been reported. We describe an OGCT that recurred after segmental resection of the mandible in a 59-year-old man. Histopathological examination revealed tumour invasion of the surrounding cortical bone, areas containing numerous calcifying flaky cell nests, and dentinoid matrix near epithelial cell nests. No atypical mitosis was found. There has been no evidence of recurrence or metastasis in the 4 years after operation.
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Neoplasias Mandibulares/patologia , Recidiva Local de Neoplasia/patologia , Tumores Odontogênicos/patologia , Dentina/patologia , Células Epiteliais/patologia , Seguimentos , Humanos , Queratinas/análise , Masculino , Mandíbula/patologia , Mandíbula/cirurgia , Neoplasias Mandibulares/cirurgia , Pessoa de Meia-Idade , Tumores Odontogênicos/cirurgiaRESUMO
We present a case of spontaneous rupture of bilateral renal angiomyolipoma (AML) with tuberous sclerosis. A 46-year-old woman was admitted with sudden onset of severe left flank pain. She had been diagnosed to have bilateral AML with tuberous sclerosis 15 years earlier. Four years after the initial diagnosis, spontaneous rupture of right renal AML occurred and right renal embolization of the right renal artery was performed. The treatment for the left renal AML was not performed. Eleven years later in 2000, spontaneous rupture of contralateral renal AML occurred and left renal embolization of the left renal artery was performed. We evaluated the efficacy of selective arterial embolization in right AML and the change of the tumor size during a 10-year follow up after embolization. The right AML had decreased 86% in 11 years. Selective arterial embolization is an effective and safe treatment for AML. We evaluated the natural history of left AML and calculated the doubling time to be about 1,370 days for the first period of 4 years and about 2,075 days for the second period of 11 years. Although the growth change was very slow, we should observe the tumors carefully on computed tomography or ultrasound to prevent life-threatening hemorrhage.