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1.
Physiol Plant ; 172(4): 1941-1949, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33749003

RESUMO

There is increasing interest in understanding how trait networks can be manipulated to improve the performance of crop species. Working towards this goal, we have identified key traits linking the acquisition of water, the transport of water to the sites of evaporation and photosynthesis, stomatal conductance, and growth across eight maize hybrid lines grown under well-watered and water-limiting conditions in Northern Colorado. Under well-watered conditions, hybrids with higher end-of-season growth and grain yield exhibited higher leaf-specific conductance, lower operating water potentials, higher rates of midday stomatal conductance, higher rates of net CO2 assimilation, and greater leaf osmotic adjustment. This trait network was similar under water-limited conditions with the notable exception that linkages between water transport, midday stomatal conductance, and growth were even stronger than under fully watered conditions. The maintenance of high leaf-specific conductance throughout the day was achieved via higher maximal conductance rates rather than lower susceptibility to conductance loss. Our results suggest that efforts to improve maize performance in well-watered and water-limiting conditions would benefit from considering the physiological trait networks governing water and carbon flux rather than focusing on single traits independently of one another.


Assuntos
Transpiração Vegetal , Zea mays , Secas , Fotossíntese , Folhas de Planta , Estômatos de Plantas , Água
2.
J Rheumatol ; 45(2): 170-176, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29142041

RESUMO

OBJECTIVE: Previous studies combining biologic disease-modifying antirheumatic drugs (bDMARD) to treat rheumatoid arthritis (RA) have shown an increased risk of infection. However, the risk of infection with concurrent use of denosumab, a biologic agent for the treatment of osteoporosis, and a bDMARD remains unclear. Here, we evaluated the incidence of serious and opportunistic infections in patients treated concurrently with denosumab and a bDMARD and patients treated with a bDMARD alone. METHODS: A chart review of patients with RA from 2 Canadian rheumatology practices between July 1, 2010, and July 31, 2014, identified 2 groups of patients: those taking denosumab and a bDMARD concurrently (concurrent group) and those taking only a bDMARD (biologic-alone group). Patients were followed from the time of initiation of denosumab, or a matched index date for the biologic-alone group, to the end of the study or loss to followup. Instances of serious or opportunistic infections were recorded. RESULTS: A total of 308 patients (n = 102 for the concurrent group and n = 206 for the biologic-alone group) were evaluated. Within the concurrent group, 3 serious infection events occurred. Within the biologic-alone group, 4 serious infection events and 1 opportunistic infection event occurred. In both groups, all patients with serious or opportunistic infection recovered, and there were no instances of death during the study period. CONCLUSION: This study demonstrated a low occurrence of serious and opportunistic infections in patients with RA taking bDMARD, including patients with concurrent denosumab use.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Produtos Biológicos/uso terapêutico , Conservadores da Densidade Óssea/uso terapêutico , Denosumab/uso terapêutico , Infecções Oportunistas/epidemiologia , Idoso , Antirreumáticos/efeitos adversos , Produtos Biológicos/efeitos adversos , Conservadores da Densidade Óssea/efeitos adversos , Canadá/epidemiologia , Estudos de Coortes , Denosumab/efeitos adversos , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Infecções Oportunistas/etiologia , Osteoporose/tratamento farmacológico , Resultado do Tratamento , Fator de Necrose Tumoral alfa/antagonistas & inibidores
3.
Plant Direct ; 2(2): e00040, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31245707

RESUMO

Efforts to increase glycinebetaine (GB) levels in plants have been pursued as an approach to improving plant performance under stress conditions. To date, the impact of engineered levels of GB has been limited by metabolic constraints that restrict the achieved increases. We report the identification of a novel gene, GB1, that is differentially expressed in high and low GB accumulating maize genotypes. The predicted GB1 protein shows 60% identity to a putative C-4 sterol methyl oxidase from rice. Overexpression of GB1 in maize and soybean led to dramatically higher leaf GB content in most of the transgenic lines compared to wild-type. These results suggest that the GB1 protein is an important component of the biochemical pathways controlling GB accumulation in plants.

4.
J Osteoporos ; 2016: 7903128, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26881176

RESUMO

Although denosumab (Prolia) has been shown to be a safe and efficacious therapy for osteoporotic patients in numerous clinical trials, few studies have determined its effectiveness in real world clinical practice. A retrospective review of patients prescribed Prolia assessing the impact that noncompliance from the regular dosing regimen of six months for denosumab has on bone mineral density (BMD) was performed. 924 patient records were reviewed between August 2012 and September 2013 with 436 patients meeting the eligibility criteria. Patients were divided into three groups: subsequent injection of denosumab (1) less than five months, (2) between five and seven months, and (3) more than seven months after their initial subcutaneous injection. A multivariable regression analysis was conducted comparing the differences among the three prespecified groups in BMD change (g/cm(2)) after one year of denosumab therapy at both the lumbar spine (LS) and femoral neck (FN). The differences in LS and FN BMD have shown that the relationship between the timing of drug administration in these three groups and change in BMD over 1 year was not clinically or statistically significant (p > 0.05). A follow-up study with a larger sample size and longer follow-up duration is required to further characterize this relationship.

6.
Proc Natl Acad Sci U S A ; 104(42): 16450-5, 2007 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-17923671

RESUMO

Commercially improved crop performance under drought conditions has been challenging because of the complexity of the trait and the multitude of factors that influence yield. Here we report the results of a functional genomics approach that identified a transcription factor from the nuclear factor Y (NF-Y) family, AtNF-YB1, which acts through a previously undescribed mechanism to confer improved performance in Arabidopsis under drought conditions. An orthologous maize transcription factor, ZmNF-YB2, is shown to have an equivalent activity. Under water-limited conditions, transgenic maize plants with increased ZmNF-YB2 expression show tolerance to drought based on the responses of a number of stress-related parameters, including chlorophyll content, stomatal conductance, leaf temperature, reduced wilting, and maintenance of photosynthesis. These stress adaptations contribute to a grain yield advantage to maize under water-limited environments. The application of this technology has the potential to significantly impact maize production systems that experience drought.


Assuntos
Proteínas de Arabidopsis/fisiologia , Arabidopsis/genética , Fator de Ligação a CCAAT/fisiologia , Desastres , Proteínas de Plantas/fisiologia , Plantas Geneticamente Modificadas/genética , Fatores de Transcrição/fisiologia , Água , Zea mays/genética , Proteínas de Arabidopsis/genética , Fator de Ligação a CCAAT/genética , Genômica , Dados de Sequência Molecular , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Subunidades Proteicas/genética , Subunidades Proteicas/fisiologia , Fatores de Transcrição/genética , Zea mays/crescimento & desenvolvimento
7.
Can Assoc Radiol J ; 58(3): 167-75, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17718300

RESUMO

OBJECTIVES: 1) To assess, with a peripheral magnetic resonance imaging system (pMRI), the prevalence of bony and soft tissue abnormalities in the knee joints of normal subjects, osteoarthritis (OA) patients, and individuals who have suffered an anterior cruciate ligament (ACL) rupture; and 2) to compare the prevalence among groups. METHODS: Magnetic resonance (MR) images of 28 healthy, 32 OA, and 26 ACL damaged knees were acquired with a 1.0-T pMRI system. Two radiologists graded the presence and severity of 9 MR image features: cartilage degeneration, osteophytes, subchondral cyst, bone marrow edema, meniscal abnormality, ligament integrity, loose bodies, popliteal cysts, and joint effusion. RESULTS: Ten of 28 healthy (35.7%), 24 of 26 ACL (92.3%), and all OA knees (100%) showed prevalent cartilage defects; 5 healthy (17.9%), 20 ACL (76.9%), and all OA knees (100%) had osteophytes; and 9 normal (32.1%), 21 ACL (80.8%), and 29 OA knees (90.6%) had meniscal abnormalities. One-half of the knees in the OA group (16 of 32, 50%) had subchondral cysts, and almost one-half had bone marrow edema (15 of 32, 46.9%). These features were not common in the ACL group (7.7%, and 11.5%, respectively) and were not observed in healthy knees. The OA group had the most severe cartilage defects, osteophytes, bone marrow edema, subchondral cysts, and meniscal abnormalities; the ACL group showed more severe cartilage defects, osteophytes, and meniscal abnormalities than did normal subjects. CONCLUSION: The results suggest that knees that have sustained ACL damage have OA-like reatures; most subjects (19 of 26, 73.1%) could be identified as in the early stage of OA. The prominent abnormalities present in ACL-damaged knees are cartilage defects, osteophytes, and meniscal abnormalities.


Assuntos
Lesões do Ligamento Cruzado Anterior , Articulação do Joelho/patologia , Imageamento por Ressonância Magnética , Osteoartrite/patologia , Adulto , Cartilagem Articular/patologia , Feminino , Humanos , Masculino , Meniscos Tibiais/patologia , Osteoartrite do Joelho/patologia , Projetos Piloto , Prevalência
8.
J Miss State Med Assoc ; 47(11): 346, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17948361
9.
BMC Musculoskelet Disord ; 6: 47, 2005 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-16143046

RESUMO

BACKGROUND: Fracture represents the single most important clinical event in patients with osteoporosis, yet remains under-predicted. As few premonitory symptoms for fracture exist, it is of critical importance that physicians effectively and efficiently identify individuals at increased fracture risk. METHODS: Of 3426 postmenopausal women in CANDOO, 40, 158, 99, and 64 women developed a new hip, vertebral, wrist or rib fracture, respectively. Seven easily measured risk factors predictive of fracture in research trials were examined in clinical practice including: age (< 65, 65-69, 70-74, 75-79, 80+ years), rising from a chair with arms (yes, no), weight (< 57, > or = 57 kg), maternal history of hip fracture (yes, no), prior fracture after age 50 (yes, no), hip T-score (> -1, -1 to > -2.5, < or = -2.5), and current smoking status (yes, no). Multivariable logistic regression analysis was conducted. RESULTS: The inability to rise from a chair without the use of arms (3.58; 95% CI: 1.17, 10.93) was the most significant risk factor for new hip fracture. Notable risk factors for predicting new vertebral fractures were: low body weight (1.57; 95% CI: 1.04, 2.37), current smoking (1.95; 95% CI: 1.20, 3.18) and age between 75-79 years (1.96; 95% CI: 1.10, 3.51). New wrist fractures were significantly identified by low body weight (1.71, 95% CI: 1.01, 2.90) and prior fracture after 50 years (1.96; 95% CI: 1.19, 3.22). Predictors of new rib fractures include a maternal history of a hip fracture (2.89; 95% CI: 1.04, 8.08) and a prior fracture after 50 years (2.16; 95% CI: 1.20, 3.87). CONCLUSION: This study has shown that there exists a variety of predictors of future fracture, besides BMD, that can be easily assessed by a physician. The significance of each variable depends on the site of incident fracture. Of greatest interest is that an inability to rise from a chair is perhaps the most readily identifiable significant risk factor for hip fracture and can be easily incorporated into routine clinical practice.


Assuntos
Fraturas Ósseas/etiologia , Osteoporose Pós-Menopausa/complicações , Idoso , Envelhecimento , Peso Corporal , Bases de Dados Factuais , Feminino , Fraturas do Quadril/etiologia , Humanos , Modelos Logísticos , Prontuários Médicos , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Fraturas das Costelas/etiologia , Fatores de Risco , Fumar/efeitos adversos , Fraturas da Coluna Vertebral/etiologia , Traumatismos do Punho/etiologia
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