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1.
J Environ Manage ; 213: 206-216, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29500994

RESUMO

Whereas soil test information on the fertility and chemistry of soils has been important to elaborate safe and sound agricultural practices, micro-scale information can give a whole extra dimension to understand the chemical processes occurring in soils. The objective of this study was to evaluate the effects that the consecutive application of untreated poultry litter, alum-treated litter or ammonium nitrate (NH4NO3) had on P solubility in soils over 20 years. For this, we used soil test data, sequential chemical fractionation (SCF) of P, and P K-edge XANES and µ-fluorescence spectroscopies. Water extractable P data indicated that application of alum to poultry litter was a very effective treatment for reducing P solubility. On the basis of our SCF of P data, P was primarily found within the 0.1 M NaOH pool across the applied rates and regardless of the treatment, where application of alum-treated litter accounted for as much as 59 ±â€¯2% of the total, followed by NH4NO3, 49 ±â€¯4%, and untreated litter, 40 ±â€¯2%. It was also shown that in soils where alum-treated litter was applied, the Resin pool accounted for 10 ±â€¯1% of the total, followed by NH4NO3, 13 ±â€¯4%, and untreated litter, 18 ±â€¯2%, indicating that P was less readily available in soils where alum-treated litter was applied. Phosphorus XANES indicated that P was predominantly associated to Fe > Al > Ca > organic molecules, regardless of the treatment or applied rates, though the formation of PoAl complexes was only found in soils that received application of alum-treated litter and was positively related to the applied rates. The combination of P-XANES with SCF or µ-fluorescence data was shown to provide valuable information about P reactivity and distribution in soils and should thus be used to address the fate of applied P amendments in soils.


Assuntos
Compostos de Alúmen/química , Esterco , Animais , Fracionamento Químico , Fósforo , Aves Domésticas , Solo
2.
Ann Oncol ; 28(4): 855-861, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28119295

RESUMO

Background: Margetuximab is an anti-HER2 antibody that binds with elevated affinity to both the lower and higher affinity forms of CD16A, an Fc-receptor important for antibody dependent cell-mediated cytotoxicity (ADCC) against tumor cells. A Phase 1 study was initiated to evaluate the toxicity profile, maximum tolerated dose (MTD), pharmacokinetics, and antitumor activity of margetuximab in patients with HER2-overexpressing carcinomas. Patients and methods: Patients with HER2-positive breast or gastric cancer, or other carcinomas that overexpress HER2, for whom no standard therapy was available, were treated with margetuximab by intravenous infusion at doses of 0.1-6.0 mg/kg for 3 of every 4 weeks (Regimen A) or once every 3 weeks (10-18 mg/kg) (Regimen B). Results: Sixty-six patients received margetuximab (34 patients for Regimen A and 32 patients for Regimen B). The MTD was not reached for either regimen. Treatment was well-tolerated, with mostly Grade 1 and 2 toxicities consisting of constitutional symptoms such as pyrexia, nausea, anemia, diarrhea, and fatigue. Among 60 response-evaluable patients, confirmed partial responses and stable disease were observed in 7 (12%) and 30 (50%) patients, respectively; 26 (70%) of these patients had received prior HER2-targeted therapy. Tumor reductions were observed in over half (18/23, 78%) of response-evaluable patients with breast cancer including durable (>30 weeks) responders. Ex vivo analyses of patient peripheral blood mononuclear cell samples confirmed the ability of margetuximab to support enhanced ADCC compared with trastuzumab. Conclusions: Margetuximab was well-tolerated and has promising single-agent activity. Further development efforts of margetuximab as single agent and in combination with other therapeutic agents are ongoing. Trial Registration ID: NCT01148849.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Antineoplásicos/administração & dosagem , Neoplasias/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/farmacocinética , Anticorpos Monoclonais/uso terapêutico , Citotoxicidade Celular Dependente de Anticorpos/efeitos dos fármacos , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacocinética , Intervalo Livre de Doença , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Receptor ErbB-2/biossíntese
3.
J Environ Qual ; 46(2): 402-410, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28380552

RESUMO

Metal runoff from fields fertilized with poultry litter may pose a threat to aquatic systems. Buffer strips located adjacent to fields may reduce nutrients and solids in runoff. However, scant information exists on the long-term effects of buffer strips combined with grazing management on metal runoff from pastures. The objective of this study was to assess the 12-yr impact of grazing management and buffer strips on metal runoff from pastures receiving poultry litter. The research was conducted using 15 watersheds (25 m wide and 57 m long) with five treatments: hayed (H), continuously grazed (CG), rotationally grazed (R), rotationally grazed with a buffer strip (RB), and rotationally grazed with a fenced riparian buffer strip (RBR). Poultry litter was applied annually in spring at 5.6 Mg ha. Runoff samples were collected after every rainfall event. Aluminum (Al) and iron (Fe) concentrations were strongly and positively correlated with total suspended solids, indicating soil erosion was the primary source. Soluble Al and Fe were not related to total Al and Fe. However, there was a strong positive correlation between soluble and total copper (Cu) concentrations. The majority of total Cu and zinc was in water-soluble form. The CG treatment had the highest metal concentrations and loads of all treatments. The RBR and H treatments resulted in lower concentrations of total Al, Cu, Fe, potassium, manganese, and total organic carbon in the runoff. Rotational grazing with a fenced riparian buffer and converting pastures to hayfields appear to be effective management systems for decreasing concentrations and loads of metals in surface runoff from pastures fertilized with poultry litter.


Assuntos
Esterco , Metais/análise , Poluentes da Água/análise , Animais , Fertilizantes , Fósforo , Aves Domésticas , Poluentes do Solo , Movimentos da Água
4.
J Environ Qual ; 46(2): 364-372, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28380550

RESUMO

High grazing pressure can lead to soil erosion in pastures, causing increased sediment delivery to waterways. The objectives of this research were to evaluate the impact of grazing management and buffer strips on soil erosion by assessing soil physical properties, hydrology, and sediment loads from pastures fertilized with broiler litter. Field studies were conducted for 12 yr on 15 small watersheds. Five management strategies were evaluated: hayed (H), continuously grazed (CG), rotationally grazed (R), rotationally grazed with a buffer strip (RB), and rotationally grazed with a fenced riparian buffer (RBR). Broiler litter was applied every year at a rate of 5.6 Mg ha. Bulk density and penetration resistance were highest for CG watersheds. Runoff volumes, sediment concentrations, and loads were lowest for the H and RBR treatments and highest for CG. Average runoff amounts were 48, 84, 77, 60, and 81 mm yr for the H, R, RB, RBR, and CG treatments, respectively. Annual average sediment loads were 25, 30, 58, 71, and 110 kg ha for H, RBR, R, RB, and CG, respectively. The Revised Universal Soil Loss Equation, Version 2 was reasonably effective at predicting soil loss for the R, RB, and RBR treatments, but it greatly overpredicted soil loss from the CG and H treatments. Converting a pasture to a hay field or using rotational grazing in conjunction with a fenced riparian buffer appear to be effective options for reducing soil erosion and runoff to waterways from pasture soils.


Assuntos
Criação de Animais Domésticos , Esterco , Solo , Animais , Bovinos , Galinhas , Conservação dos Recursos Naturais , Movimentos da Água , Poluentes da Água
5.
J Environ Qual ; 45(5): 1565-1571, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27695743

RESUMO

Regions with long-term animal manure applications based on nitrogen (N) requirements have concerns regarding elevated nutrient levels. Most attention has focused on phosphorus (P), but heavy metal accumulation has received attention due to perceived environmental concerns. Composting is a potential management practice that can reduce total manure mass and volume while creating a stabilized product that has less odor and fewer pathogens. However, composting animal manures can lead to high N loss via ammonia volatilization and increased concentrations of nonvolatile nutrients. The objective of this study was to measure copper (Cu) and zinc (Zn) concentrations in runoff water from plots fertilized with composted and fresh poultry litter. Seven treatments were evaluated in the first year: (i) unfertilized control, (ii) fresh poultry litter, (iii) normal compost (no amendment), (iv) composted litter with alum, (v) composted litter with phosphoric acid, (vi) composted litter with a microbial mixture, and (vii) composted litter with alum + microbial mixture. Six of these treatments were evaluated in Year 2 (alum + microbial mixture was not evaluated in Year 2). Rainfall simulators were used to produce a 5 cm h storm event sufficient in length to cause 30 min of continuous runoff. Concentrations of Cu and Zn were elevated in compost compared with fresh poultry litter. However, metal concentrations in compost did not correlate well with metal concentrations in runoff water and may have been affected by compost maturity and amendment. Total Cu and Zn concentrations in runoff water did not differ between alum-amended compost and fresh poultry litter in each year.


Assuntos
Cobre/análise , Esterco , Zinco/análise , Animais , Fósforo , Aves Domésticas , Movimentos da Água
6.
J Environ Qual ; 43(4): 1417-23, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25603088

RESUMO

Arsenic (As) and copper (Cu) runoff from fields fertilized with poultry litter has received increasing attention in recent years, although it is not known if heavy metal runoff from poultry litter poses a significant threat to the environment. The objective of this study was to determine the main factors affecting As and Cu concentrations in runoff water from pastures receiving poultry litter applications. Rainfall simulation studies were conducted to determine the effects of the following treatments on metal runoff: (i) aluminum sulfate (alum) additions, (ii) diet modification using phytase or high available phosphorus corn, (iii) fertilizer type, (iv) poultry litter application rate, and (v) time until the first runoff event occurs after poultry litter application. Results showed that alum additions to poultry litter significantly decreased As and Cu concentrations in runoff water. Copper concentrations were highest in runoff from poultry litter from birds fed phytase diets compared with other diets; however, this effect may have been a result of wet storage conditions rather than diet. Triple superphosphate applications resulted in the lowest heavy metal concentrations in runoff water among all fertilizer treatments, while normal poultry litter resulted in the highest concentrations. Arsenic and Cu concentrations increased in runoff water as poultry litter application rates increased and decreased with increasing time until the first runoff event. These data indicate that adding alum to poultry litter, a cost-effective best management practice, which also results in lower P runoff and ammonia emissions, may also be an effective tool in reducing metal runoff.

7.
J Environ Qual ; 43(4): 1119-24, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25603060

RESUMO

Complex variation in gas emissions from animal facilities has been shown in recent research reports. Uncertainties in these emission estimates are driving research activities concerning different animal species across the globe. Greenhouse gas (NO and CO) and NH concentrations were measured in a modern, tunnel-ventilated, commercial broiler house in Mississippi during five flocks (spanning approximately 1 yr). These were flocks 9 through 13 on reused pine shavings litter, representing litter reuse beyond 2 yr. Gas concentrations obtained from a photoacoustic multigas analyzer were coupled with ventilation measurements of air flow through the house to develop NH and NO emission rates. Ammonia emission during a flock (43 d) averaged approximately 14.8 ± 9.8 kg d in the commercial house (equivalent to 23.5 g bird marketed or 0.54 g bird d). Nitrous oxide emission averaged 2.3 ± 1.7 kg d in the house (equivalent to 3.64 g bird marketed or 0.085 g bird d). Emission rates increased with time from Day 1 to Day 43 and reached average values on Day 23 and 24 for NH and NO. Even with extended litter reuse, estimates of NH emissions from the broiler house agree well with recently published research that reused litter in eight or fewer flocks. This is important information for farmers who may not be able to afford to replace the litter with fresh bedding material annually.

8.
Integr Org Biol ; 6(1): obae033, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39286800

RESUMO

Many prey organisms respond to the nonconsumptive effects of predators by altering their physiology, morphology, and behavior. These inducible defenses can create refuges for prey by decreasing the likelihood of consumption by predators. Some prey, as in marine mollusks, have been shown to alter their morphology in response to the presence of size-limited predation. To extend this work, we exposed pointed campeloma snails (Campeloma decisum) to chemical cues from a natural predator, the rusty crayfish (Faxonius rusticus), to better understand how snail morphology changes under the threat of predation. The total force needed to crush shells, total shell length, aperture width, and total weight, along with changes to these 3 body measurements, were recorded for each individual and used to quantify morphological changes as a function of risk. Snails exposed to crayfish chemical cues had shells that required significantly more force to crush their shells than controls (P = 0.023). Total shell length was greater in crayfish-exposed snails than in control snails (P = 0.012), and snails in the crayfish treatment also showed significantly more change in shell length than control snails (P = 0.007). Similarly, aperture width was significantly greater in exposed snails (P = 0.011). However, exposed snails exhibited significantly less change in aperture width than controls (P = 0.03). Finally, we found that snails exposed to crayfish weighed significantly more than snails in the control (P = 0.008). Thus, the results of this study show that morphology of gastropods is altered in the presence of predators, and this may be an antipredator tactic directly related to predation risk.

9.
J Environ Qual ; 52(1): 88-99, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36314063

RESUMO

Information on how forage species influence sediment and nutrient transport in runoff is required for limiting non-point source pollution from broiler litter applications. In this study, we examined the effects of five forage species (eastern gamagrass [Tripsacum dactyloides (L.) L.], Kernza [Thinopyrum intermedium (Host) Barkworth & D.R. Dewey], silphium [Silphium integrifolium Michx.], switchgrass [Panicum virgatum L.], and winter wheat [Triticum aestivum L.]) on runoff nutrient losses from broiler litter-amended (5.6 Mg ha-1 ) and non-amended plots (control) following four simulated rainfall (5 cm h-1 ) events that were applied to these plots in late spring and early fall of 2019 and 2021. Runoff collected for 30 min was analyzed for total suspended solids (TSS) and nutrients (total organic carbon [TOC], soluble reactive phosphorus [SRP], total dissolved phosphorus [TDP], total phosphorus [TP], total nitrogen [TN], ammonium-nitrogen [NH4 -N], and nitrate-nitrogen [NO3 -N]). Total sediment and nutrient losses increased 5- to 19-fold following litter application for all species, which reduced to background levels during fall rainfall events. Across the four simulated rainfall events, switchgrass resulted in lower cumulative losses of TSS, TOC, SRP, TDP, TP, and NO3 -N than gamagrass and wheat but did not differ from Kernza and silphium for litter-amended treatments. The performance of newly introduced perennial crops (Kernza and silphium) was similar or better than that of gamagrass in terms of cumulative runoff sediment and nutrient losses. Results show high potential for Kernza, silphium, and switchgrass to improve water quality when used in forage-vegetative filter strip systems.


Assuntos
Galinhas , Panicum , Animais , Esterco , Nitrogênio/análise , Nutrientes , Triticum , Fósforo , Chuva , Proteínas de Ligação a DNA , Movimentos da Água
10.
J Dent Res ; 102(4): 391-401, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36631957

RESUMO

This study compares the effectiveness of pharmacological treatments to develop guidelines for the management of acute pain after tooth extraction. We searched Medline, EMBASE, CENTRAL, and US Clinical Trials registry on November 21, 2020. We included randomized clinical trials (RCTs) of participants undergoing dental extractions comparing 10 interventions, including acetaminophen, nonsteroidal anti-inflammatory drugs (NSAIDs), opioids, and combinations to placebo. After duplicate screening and data abstraction, we conducted a frequentist network meta-analysis for each outcome at 6 h (i.e., pain relief, total pain relief [TOTPAR], summed pain intensity difference [SPID], global efficacy rating, rescue analgesia, and adverse effects). We assessed the risk of bias using a modified Cochrane RoB 2.0 tool and the certainty of evidence using the Grading of Recommendations, Assessment, Development, and Evaluation approach. We implemented the analyses in RStudio version 3.5.3 and classified interventions from most to least beneficial or harmful. We included 82 RCTs. Fifty-six RCTs enrolling 9,095 participants found moderate- and high-certainty evidence that ibuprofen 200 to 400 mg plus acetaminophen 500 to 1,000 mg (mean difference compared to placebo [MDp], 1.68; 95% confidence interval [CI], 1.06-2.31), acetaminophen 650 mg plus oxycodone 10 mg (MDp, 1.19; 95% CI, 0.85-1.54), ibuprofen 400 mg (MDp, 1.31; 95% CI, 1.17-1.45), and naproxen 400-440 mg (MDp, 1.44; 95% CI, 1.07-1.80) were most effective for pain relief on a 0 to 4 scale. Oxycodone 5 mg, codeine 60 mg, and tramadol 37.5 mg plus acetaminophen 325 mg were no better than placebo. The results for TOTPAR, SPID, global efficacy rating, and rescue analgesia were similar. Based on low- and very low-certainty evidence, most interventions were classified as no more harmful than placebo for most adverse effects. Based on moderate- and high-certainty evidence, NSAIDs with or without acetaminophen result in better pain-related outcomes than opioids with or without acetaminophen (except acetaminophen 650 mg plus oxycodone 10 mg) or placebo.


Assuntos
Acetaminofen , Dor Aguda , Adulto , Humanos , Acetaminofen/uso terapêutico , Ibuprofeno/uso terapêutico , Oxicodona/uso terapêutico , Metanálise em Rede , Anti-Inflamatórios não Esteroides/uso terapêutico , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/etiologia , Analgésicos Opioides/uso terapêutico , Extração Dentária/efeitos adversos , Dor Aguda/tratamento farmacológico , Dor Aguda/etiologia
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