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1.
J Exp Bot ; 72(14): 5235-5245, 2021 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-34037765

RESUMO

Because plants capture water and nutrients through roots, it was proposed that changes in root systems architecture (RSA) might underpin the 3-fold increase in maize (Zea mays L.) grain yield over the last century. Here we show that both RSA and yield have changed with decades of maize breeding, but not the crop water uptake. Results from X-ray phenotyping in controlled environments showed that single cross (SX) hybrids have smaller root systems than double cross (DX) hybrids for root diameters between 2465 µm and 181µm (P<0.05). Soil water extraction measured under field conditions ranged between 2.6 mm d-1 and 2.9 mm d-1 but were not significantly different between SX and DX hybrids. Yield and yield components were higher for SX than DX hybrids across densities and irrigation (P<0.001). Taken together, the results suggest that changes in RSA were not the cause of increased water uptake but an adaptation to high-density stands used in modern agriculture. This adaptation may have contributed to shift in resource allocation to the ear and indirectly improved reproductive resilience. Advances in root physiology and phenotyping can create opportunities to maintain long-term genetic gain in maize, but a shift from ideotype to crop and production system thinking will be required.


Assuntos
Secas , Zea mays , Agricultura , Melhoramento Vegetal , Solo , Água , Zea mays/genética
2.
J Surg Res ; 225: 131-141, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29605023

RESUMO

BACKGROUND: This study is the first to analyze penetrating injuries to the pancreas within subgroups of severe traumatic brain injury (TBI), early deaths, and potential survivors. Our objectives were to identify national patterns of injury, predictors of mortality, and to validate the American Association for Surgery of Trauma Organ Injury Scale (AAST-OIS) pancreas injury grades by mortality. Secondary outcomes included hospital and intensive care unit length of stay and days on mechanical ventilation. METHODS: Using the Abbreviated Injury Scale 2005 and ICD-9-CM E-codes, we identified 777 penetrating pancreatic trauma patients from the National Trauma Data Bank that occurred between 2010 and 2014. Severe TBI was identified by ICD-9-CM diagnosis codes and Glasgow Coma Score (GCS; n = 7), early deaths were those that occurred within 24 h of admission (n = 82), and potential survivors included patients without severe TBI who survived longer than 24 h following admission (n = 690). We estimated multivariable generalized linear mixed models to predict mortality to account for the nesting of potential survivors within trauma centers. RESULTS: Our results indicated that overall mortality decreased from 16.9% to 6.8% after excluding severe TBI and early deaths. Approximately, 11% of patients died within 24 h of admission, of whom 78% died in the first 6 h. Associated injuries to the stomach, liver, and major vasculature occurred in approximately 50% of patients; rates of associated injuries were highest in patients who died within 6 h of admission. In potential survivors, mortality increased by AAST-OIS grade: 3.5% I/II; 8.3% III; 9.6% IV; and 13.8% V. Predictors of mortality with significantly increased odds of death were patients with increasing age, lower admission GCS, higher admission pulse rate, and more severe injuries as indicated by Organ Injury Scale grade. CONCLUSIONS: From 777 patients, we identified national patterns of injury, predictors of outcome, and mortality by AAST-OIS grade within the subgroups of severe TBI, early deaths, and potential survivors. Because AAST-OIS is not a reported element in the National Trauma Data Bank, we correlated Abbreviated Injury Scale 2005 codes to injury grade and identified an increase in mortality. After controlling for covariance, we found that greater age, lower GCS in stab wounds, higher pulse, and presence of a grade V pancreatic injury independently predicted the likelihood of death in patients surviving beyond 24 h following penetrating injuries to the pancreas.


Assuntos
Bases de Dados Factuais/estatística & dados numéricos , Mortalidade Hospitalar/tendências , Pâncreas/lesões , Índices de Gravidade do Trauma , Ferimentos Penetrantes/diagnóstico , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Prognóstico , Pulso Arterial/mortalidade , Sobreviventes/estatística & dados numéricos , Fatores de Tempo , Centros de Traumatologia/estatística & dados numéricos , Ferimentos Penetrantes/mortalidade , Adulto Jovem
3.
Biotechnol Bioeng ; 106(4): 627-37, 2010 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-20229510

RESUMO

Pre-filtration using ion exchange membrane adsorbers can improve parvovirus filter throughput of monoclonal antibodies (mAbs). The membranes work by binding trace foulants, and although some antibody product also binds, yields > or =99% are easily achieved by overloading. Results show that foulant adsorption is dependent on pH and conductivity, but independent of scale and adsorber brand. The ability to use ion exchange membranes as pre-filters is significant because it provides a clean, well defined, chemically stable option for enhancing throughput. Additionally, ion exchange membranes facilitate characterization of parvovirus filter foulants. Examination of adsorber elution samples using sedimentation velocity analysis and SEC-MALS/QELS revealed the presence of high molecular weight species ranging from 8 to 13 nm in hydrodynamic radius, which are similar in size to parvoviruses and thus would be expected to plug the pores of a parvovirus filter. A study of two identical membranes in-series supports the hypothesis that the foulants are soluble, trace level aggregates in the feed. This study's significance lies in a previously undiscovered application of membrane chromatography, leading to a more cost effective and robust approach to parvovirus filtration for the production of monoclonal antibodies.


Assuntos
Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/isolamento & purificação , Filtração/métodos , Parvovirus/isolamento & purificação , Meios de Cultura/química , Condutividade Elétrica , Concentração de Íons de Hidrogênio , Troca Iônica , Membranas
4.
Matter ; 3(3): 805-823, 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32838298

RESUMO

This work describes the design and implementation of an automated device for catalytic materials testing by direct modifications to a gas chromatograph (GC). The setup can be operated as a plug-flow isothermal reactor and enables the control of relevant parameters such as reaction temperature and reactant partial pressures directly from the GC. High-quality kinetic data (including reaction rates, product distributions, and activation barriers) can be obtained at almost one-tenth of the fabrication cost of analogous commercial setups. With these key benefits including automation, low cost, and limited experimental equipment instrumentation, this implementation is intended as a high-throughput catalyst screening reactor that can be readily utilized by materials synthesis researchers to assess the catalytic properties of their synthesized structures in vapor-phase chemistries.

5.
J Trauma Acute Care Surg ; 83(5): 810-817, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28658014

RESUMO

BACKGROUND: Despite wide belief that the duodenal Organ Injury Scale has been validated, this has not been reported in the published literature. Based on clinical experience, we hypothesize that the American Association for Surgery of Trauma Organ Injury Scale (AAST-OIS) for duodenal injuries can independently predict mortality. Our objectives were threefold: (1) describe the national profile of penetrating duodenal injuries, (2) identify predictors of morbidity and mortality, and (3) validate the duodenum AAST-OIS as a statistically significant predictor of mortality. METHODS: Using the Abbreviated Injury Scale 2005 and International Classification of Diseases-9th Rev.-Clinical Modification (ICD-9-CM) E-codes, we identified 879 penetrating duodenal trauma patients from the National Trauma Data Bank between 2010 and 2014. We controlled patient-level covariates of age, biological sex, systolic blood pressure (SBP), Glasgow Coma Scale (GCS) score, pulse, Injury Severity Score (ISS), and Organ Injury Scale (OIS) grade. We estimated multivariable generalized linear mixed models to account for the nesting of patients within trauma centers. RESULTS: Our results indicated an overall mortality rate of 14.4%. Approximately 10% of patients died within 24 hours of admission, of whom 76% died in the first 6 hours. Patients averaged approximately five associated injuries, 45% of which involved the liver and colon. Statistically significant independent predictors of mortality were firearm mechanism, SBP, GCS, pulse, ISS, and AAST-OIS grade. Specifically, odds of death were decreased with 10 mm Hg higher admission SBP (13% decreased odds), one point higher GCS (14.4%), 10-beat lower pulse (8.2%), and 10-point lower ISS (51.0%). CONCLUSION: This study is the first to report the national profile of penetrating duodenal injuries. Using the National Trauma Data Bank, we identified patterns of injury, predictors of outcome, and validated the AAST-OIS for duodenal injuries as a statistically significant predictor of morbidity and mortality. LEVEL OF EVIDENCE: Epidemiologic/Prognostic, level IV.


Assuntos
Traumatismos Abdominais/mortalidade , Duodeno/lesões , Índices de Gravidade do Trauma , Ferimentos Penetrantes/mortalidade , Escala Resumida de Ferimentos , Traumatismos Abdominais/classificação , Adulto , Comorbidade , Bases de Dados como Assunto , Feminino , Humanos , Escala de Gravidade do Ferimento , Classificação Internacional de Doenças , Masculino , Análise Multivariada , Prognóstico , Sociedades Médicas , Traumatologia , Estados Unidos/epidemiologia , Adulto Jovem
6.
J Clin Oncol ; 33(18): 2013-20, 2015 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-25800770

RESUMO

PURPOSE: Blockade of the programmed death-1 inhibitory cell-surface molecule on immune cells using the fully human immunoglobulin G4 antibody nivolumab mediates tumor regression in a portion of patients with advanced treatment-refractory solid tumors. We report clinical activity, survival, and long-term safety in patients with advanced renal cell carcinoma (RCC) treated with nivolumab in a phase I study with expansion cohorts. PATIENTS AND METHODS: A total of 34 patients with previously treated advanced RCC, enrolled between 2008 and 2012, received intravenous nivolumab (1 or 10 mg/kg) in an outpatient setting once every two weeks for up to 96 weeks and were observed for survival and duration of response after treatment discontinuation. RESULTS: Ten patients (29%) achieved objective responses (according to RECIST [version 1.0]), with median response duration of 12.9 months; nine additional patients (27%) demonstrated stable disease lasting > 24 weeks. Three of five patients who stopped treatment while in response continued to respond for ≥ 45 weeks. Median overall survival in all patients (71% with two to five prior systemic therapies) was 22.4 months; 1-, 2-, and 3-year survival rates were 71%, 48%, and 44%, respectively. Grade 3 to 4 treatment-related adverse events occurred in 18% of patients; all were reversible. CONCLUSION: Patients with advanced treatment-refractory RCC treated with nivolumab demonstrated durable responses that in some responders persisted after drug discontinuation. Overall survival is encouraging, and toxicities were generally manageable. Ongoing randomized clinical trials will further assess the impact of nivolumab on overall survival in patients with advanced RCC.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Antineoplásicos/administração & dosagem , Carcinoma de Células Renais/tratamento farmacológico , Neoplasias Renais/tratamento farmacológico , Adulto , Idoso , Carcinoma de Células Renais/mortalidade , Estudos de Coortes , Intervalo Livre de Doença , Relação Dose-Resposta a Droga , Feminino , Humanos , Neoplasias Renais/mortalidade , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Nivolumabe , Segurança do Paciente , Receptor de Morte Celular Programada 1/imunologia , Fatores de Tempo , Resultado do Tratamento
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