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1.
Eur J Paediatr Dent ; 18(1): 37-40, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28494601

RESUMO

AIM: Most scientific literature relates vertical growth to individuals with decreased upper airway permeability. However, we often find subjects with a long face and a normal breathing pattern, most likely caused by other aetiological factors. And, frequently, we also find decreased upper airway permeability with horizontal growth. The aim of the study was to compare the cephalometric measurements of the oro and nasopharynx permeability with the facial growth direction and to identify the most common facial growth direction in individuals with decreased upper airway permeability. MATERIALS AND METHODS: Cephalometric analysis was carried out in 158 pre-adolescent patients at the Orthodontic appointment, using facial profile teleradiographs. Parameters used were Jabarak's ratio and measurement of oro-nasopharynx space. Data collected were submitted to statistical treatment. RESULTS: This study points to the presence of an intermediate growth in individuals with diminished oro and nasopharynx permeability, either simultaneous or separate. The number of individuals with diminished permeability and vertical growth is close to the number of individuals with horizontal growth. CONCLUSIONS: The individuals with diminished permeability of the upper airway present an intermediate growth direction, representing the most frequent type. In the less common growth directions, there is a slight tendency to horizontal facial growth verified in individuals with diminished nasopharynx permeability. Also, a light tendency to vertical facial growth is present when oropharynx permeability is reduced.


Assuntos
Desenvolvimento Maxilofacial , Nasofaringe/crescimento & desenvolvimento , Orofaringe/crescimento & desenvolvimento , Adolescente , Pontos de Referência Anatômicos , Cefalometria , Criança , Feminino , Humanos , Masculino , Nasofaringe/diagnóstico por imagem , Orofaringe/diagnóstico por imagem , Dimensão Vertical
2.
Eur J Paediatr Dent ; 17(4): 301-306, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28045318

RESUMO

AIM: The study evaluated the presence of non-nutritive sucking habits and and their effects on the occlusion in the deciduos dentition in Spanish children. MATERIALS AND METHODS: Study design: Cross-sectional survey. A clinical examination was performed by an experienced examiner in 275 children aged 3 to 6 years and the collected data included the presence of anterior open bite (vertical dimension), unilateral or bilateral posterior crossbite (transverse dimensions), midline deviation and sagittal relationships between incisors, molars and canines. In addition, the parents of each child completed a questionnaire about oral habits. Data analysis included descriptive statistics (frequency distribution). Statistical significance for the association between the non-nutritive sucking habits and development of malocclusion was determined using Chi-square and Fisher's exact tests. Multiple logistic regression analysis was used in order to adjust the results for confounding effects of non-nutritive habits before assessing statistical significance. RESULTS: Non-nutritive sucking habit was observed in 224 children (81.5%) and malocclusions were present in 152 children (55.2%). There were significant relationships between pacifier sucking habit and transverse dimension alteration (OR= 3.29, CI: 0.97- 11.17, p=0.044), midline deviation (OR= 3.00, CI: 1.22-7.38, p=0.013). Children with a history of finger sucking (or thumb sucking) had an increased risk of malocclusion 4.25 times higher (CI: 0.92-19.58, p=0.044) and there was a significant relationship between finger sucking and vertical relationship (OR= 8.25, CI: 2.50-27.25, p=0.001). Children with non- nutritive sucking habits had an increased risk of malocclusion 2.55 higher compared to those without non-nutritive sucking habits (p=0.004). CONCLUSION There was an impact of non-nutritive sucking habit and development of malocclusions in this sample of children.


Assuntos
Sucção de Dedo/efeitos adversos , Hábitos , Má Oclusão/etiologia , Chupetas/efeitos adversos , Dente Decíduo , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Masculino , Inquéritos e Questionários
3.
Asian-Australas J Anim Sci ; 27(7): 981-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25050040

RESUMO

The objective of the present study was to investigate the effects of a mixture of functional oils (Essential, Oligo Basics Agroind. Ltda) on performance response of chickens challenged with coccidiosis and the determination of apparent metabolizable energy (AME), nitrogen-corrected apparent metabolizable energy (AMEn), the coefficients of protein and ether extract digestibility and intestinal morphology of broilers fed with diets containing Essential. In Exp. 1, a completely randomized design (CRD) was used, with one control diet without Essential inclusion with coccidiosis (Eimeria acervulina, Eimeria maxima, and Eimeria tenella) challenged birds and two different inclusion rates of Essential (1.5 kg/ton and 2 kg/ton) with coccidiosis-challenged and non-challenged birds for each inclusion rate, using 10 replicates and 50 birds per experimental unit. After 7 d of coccidiosis challenge, the livability was approximately 10% lower (p<0.05) for the control group. Intestinal lesion scores were lower (p<0.05) in the anterior intestine and the cecum for the chickens supplemented. Feed efficiency and growth rate were improved in birds supplemented with Essential (p<0.05) before the coccidiosis challenge and during the first 7 d post infection. In Exp. 2, a CRD was used, with one control diet without Essential inclusion and one diet with inclusion of Essential (1.5 kg/ton), using nine replications and 33 chicks per pen. The diets with Essential yielded approximately 4% higher AME (p = 0.003) and AMEn (p = 0.001). Essential supplementation increased villus height in the jejunum on d 14 (p<0.05). Villus height:crypt depth ratio for the supplemented birds was larger (p<0.05) in the jejunum on d 7, larger (p<0.05) in the jejunum and ileum on d 14. In conclusion, these functional oils improved the energy utilization and the livability and decreased lesions caused by coccidiosis in supplemented birds.

4.
Eur J Paediatr Dent ; 11(2): 87-92, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20635843

RESUMO

AIM: Several organizations consider mother's milk the optimal nutrition source for newborns [AAP, 1998; Gartner et al., 1997; Mohrbacher and Stock, 2002; WHO, 1989]. However, there is little scientific evidence supporting the idea that breastfeeding has a positive influence on the development of the orofacial structures. MATERIALS AND METHODS: The study of cases and controls (observational, analytical and retrospective) and lateral teleradiographs of the cranium of 197 patients (106 breast-fed and 91 bottle-fed) were compared. Ricketts, Steiner and McNamara values were used for the cephalometric analysis. Differences between the two groups were analysed by applying the T-test and ANOVA. Statistical significance levels were set at p<0.05. Non-nutritive infantile sucking habits have been compared; differences between the two groups were analysed by applying the Chi-square test. RESULTS: First, the upper incisors were found to be protruded in the bottle-fed group. Second, subjects belonging to the breast-fed group displayed a brachycephalic mandible arch, while those fed with bottle had a dolichocephalic Steiner mandibular plane. Third, both facial depth and distance of the pogonion to the perpendicular nasion presented a certain tendency to a retruded mandibular bone in the bottle-fed group. And fourth, the frequency of use of dummy and thumb suction were greater in the bottle feed group, without statistical significance. CONCLUSION: In addition to the multiple advantages that mother's milk offers to newborns, breastfeeding also helps correct orofacial development (not only for the incisors position, but also for the vertical and sagittal relations of the mandible with upper maxillary and cranial basis).


Assuntos
Alimentação com Mamadeira , Aleitamento Materno , Desenvolvimento Maxilofacial , Alimentação com Mamadeira/efeitos adversos , Cefalometria , Criança , Face/anatomia & histologia , Feminino , Sucção de Dedo/efeitos adversos , Humanos , Incisivo/patologia , Masculino , Má Oclusão/etiologia , Radiografia , Fatores Sexuais , Crânio/anatomia & histologia , Crânio/diagnóstico por imagem
5.
Poult Sci ; 99(7): 3752-3760, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32616271

RESUMO

Two experiments were conducted to evaluate the effects of functional oils containing cashew nutshell and castor oil on turkey performance and intestinal morphology. In experiment 1, 585 hatchlings were randomly placed in 15 replicate floor pens, (13 poults/pen) with recycled litter and provided feed and water ad libitum. Birds were randomly assigned to 3 dietary treatments from 1 to 12 wk: nonmedicated control, 0.15% functional oils, and 66-ppm monensin. From wk 13 to 20, each initial treatment group was further divided into 3 treatments-control (no additive), 0.15% of functional oils, or 20 ppm of virginiamycin to produce 9 different treatments, 5 replicate pens per treatment. Data on feed weights were collected weekly, and body weight bi-weekly. At termination (20 wk), birds were euthanized, and their meat was processed to determine mass of carcass sections and meat quality, while intestinal samples were collected for histology. In experiment 1, toms fed monensin or functional oils were 10.5 and 4.5% heavier (P < 0.05), respectively, than the controls at 12 wk. Birds fed monensin had a 4% improvement (P < 0.05) in feed conversion as compared to the other treatments. Neither virginiamycin nor the functional oils affected bird performance when fed from 13 to 20 wk. The jejunum villi surface area at 3 wk was most enhanced (P < 0.05) for the poults fed monensin. Supplementation with functional oils significantly reduced leg yield and thiobarbituric-acid reactive substances of white meat after 7 D of storage (P < 0.05). There were no effects on performance or carcass characteristics in experiment 2. While additional confirmatory studies are needed, functional oils in the diet of turkey toms may be a viable alternative to antibiotic growth promotants.


Assuntos
Ração Animal/análise , Gorduras Insaturadas na Dieta/administração & dosagem , Intestinos/efeitos dos fármacos , Carne/análise , Perus/fisiologia , Animais , Dieta/veterinária , Intestinos/anatomia & histologia , Masculino , Perus/anatomia & histologia , Perus/crescimento & desenvolvimento
7.
Poult Sci ; 98(11): 5855-5861, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31329962

RESUMO

As antioxidants such as some functional oils are good candidates to mitigate heat stress, a commercial blend of functional oils (Essential, Oligo Basics USA LLC, Cary, NC; active ingredients: cashew nut shell oil and castor oil) was used to study the effects of two ambient temperatures (moderate and high) on broiler chicken performance and carcass parameters. A total of 2,240 straight-run one-day-old chickens were sorted by weight, randomized among 28 floor pens with 80 chickens per pen and 7 replicates for each treatment. Birds were assigned to one of 4 dietary treatments in a 2 × 2 factorial arrangement with two temperature environments (moderate and high) and without or with Essential supplementation (1.5 kg/ton). Variances for the average temperature, relative humidity, and dew point for the two environments were different (P < 0.001), showing that the high-temperature environment reached higher temperatures and dew points. Essential supplementation increased body weight gain at 42 D of age (2.548 vs. 2.508 kg; P < 0.01) and tended to improve feed conversion (1.621 vs. 1.644; P = 0.09) independent of temperature environment. The high-temperature environment increased mortality (7.5 vs. 12.4%; P = 0.03) and carcass yields (77.5 vs. 76.2%; P < 0.01). Breast yields were affected by an environment by Essential interaction (P < 0.01). Whereas the high-temperature environment decreased breast yield in control birds, it did not decrease breast yield in birds supplemented with Essential. Finally, breast yields were increased by Essential supplementation (23.6 vs. 22.9%; P < 0.01) regardless of the ambient temperature. In conclusion, Essential supplementation improved weight gains and carcass characteristics, and high-temperature environments decreased breast yields when Essential was not supplemented.


Assuntos
Anacardium/química , Óleo de Rícino/metabolismo , Galinhas/fisiologia , Temperatura Alta , Carne/análise , Óleos de Plantas/metabolismo , Ração Animal/análise , Animais , Óleo de Rícino/administração & dosagem , Galinhas/crescimento & desenvolvimento , Dieta/veterinária , Suplementos Nutricionais/análise , Masculino , Óleos de Plantas/administração & dosagem
8.
Clin Transl Oncol ; 10(6): 351-8, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18558582

RESUMO

INTRODUCTION: Asthenia is the most prevalent symptom in oncological patients but it is underestimated by the majority of healthcare professionals. The aim of the present study is to estimate the prevalence of tumour-related asthenia in the Spanish population, while defining the associated factors. METHODS: An epidemiological, multicentre, cross-sectional study was conducted in oncology services from Spain, including 712 cancer patients (58.4+/-13.5 years). RESULTS: 42.5% patients showed asthenia. This prevalence appeared to be tumour-related (p<0.05) and increased among patients with a more advanced stage of disease or with a worsening of performance status (p<0.001). The prevalence of asthenia increased in the presence of the following factors: chemotherapy (in the past: 52.1% vs. 31.0%; at the time of the study: 46.1% vs. 38.2%), symptomatic treatment (in the past: 60.4% vs. 39.8%; at the time of the study: 61.3% vs. 38.6%), present interferon treatment (100%), anaemia (59.7% vs. 31.3%), dehydration/waterelectrolyte imbalance (58.3% vs. 41.6%), respiratory failure (61.4% vs. 39.7%), liver disease (59.5% vs. 41.3%), malnutrition (76.1% vs. 38.7%), pain (57.7% vs. 27.0%), anxiety (56.1% vs. 38.6%), depression (57.9% vs. 40.0%) and sleep disturbances (51.1% vs. 39.4%). A multivariate logistic regression showed that a model including performance status, patient circumstance, chemotherapy, anaemia, pain and anxiety correctly diagnosed asthenia in 70.9% of cases. CONCLUSIONS: The physiopathology of tumour-related asthenia remains relatively unknown, despite its high prevalence and considerable quality of life impact. Determining factors related to asthenia in clinical practice can favour the use of concrete treatments and improve the conditions of cancer patients.


Assuntos
Astenia/epidemiologia , Astenia/etiologia , Neoplasias/complicações , Antineoplásicos/efeitos adversos , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Prevalência , Qualidade de Vida , Espanha/epidemiologia
9.
An Pediatr (Barc) ; 69(4): 304-10, 2008 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-18928696

RESUMO

INTRODUCTION: The 22q11.2 deletion syndrome is a contiguous gene deletion syndrome with an incidence rate of 1/4,000-6,000 live births. The most specific clinical features are: congenital conotruncal heart diseases, palate anomalies, hypocalcaemia, immunity and learning problems, and a characteristic facial phenotype. The objective of this work is to review the presenting phenotype and clinical features of children with 22q11.2 deletion syndrome as a guide for early diagnosis. PATIENTS AND METHODS: Retrospective study of 22 patients with 22q11.2 deletion syndrome diagnosed at our hospital in the time period 2004-2007. Variables analyzed: incidence, sex, age at diagnosis, presenting phenotype, clinical features, positive family history, mortality and natural history. RESULTS: From a total of 22 patients, 63 % were males, and the median age at diagnosis was of 4.5 years. Presenting pheno-type: congenital heart disease, milestones delay, velopharyngeal incompetence, hypocalcaemia, and mental retardation/psychiatric disturbances. CLINICAL FEATURES: congenital heart disease (84 %), velopharyngeal incompetence (47 %), milestones delay and learning disabilities (79 %). All of the deletions were de novo, except in one case where the deletion was present as mosaicism in the father. Three patients died, due to congenital heart disease. CONCLUSIONS: Clinical expression is widely variable, although a characteristic phenotype exists. Patients with heart disease are diagnosed earlier than other patients with unusual presenting phenotype such as congenital dysphagia. It is important to recognize less common phenotypes at early ages in order to provide multidisciplinary monitoring and accurate genetic counselling.


Assuntos
Síndrome de DiGeorge/diagnóstico , Síndrome de DiGeorge/genética , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Fenótipo , Estudos Retrospectivos , Adulto Jovem
10.
Biochim Biophys Acta ; 1764(3): 461-9, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16388998

RESUMO

This paper gives an overview of the application of high-pressure to study the folding/unfolding processes of proteins using Ribonuclease A as a model protein. A particular focus is the study of pressure-equilibrium unfolding and folding kinetics using variants and the information obtained by comparing these with the wild-type enzyme.


Assuntos
Dobramento de Proteína , Ribonuclease Pancreático/química , Animais , Humanos , Pressão , Conformação Proteica , Ribonuclease Pancreático/genética
11.
Braz J Med Biol Res ; 38(8): 1175-83, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16082457

RESUMO

The pressure behavior of proteins may be summarized as a the pressure-induced disordering of their structures. This thermodynamic parameter has effects on proteins that are similar but not identical to those induced by temperature, the other thermodynamic parameter. Of particular importance are the intermolecular interactions that follow partial protein unfolding and that give rise to the formation of fibrils. Because some proteins do not form fibrils under pressure, these observations can be related to the shape of the stability diagram. Weak interactions which are differently affected by hydrostatic pressure or temperature play a determinant role in protein stability. Pressure acts on the 2 degrees, 3 degrees and 4 degrees structures of proteins which are maintained by electrostatic and hydrophobic interactions and by hydrogen bonds. We present some typical examples of how pressure affects the tertiary structure of proteins (the case of prion proteins), induces unfolding (ataxin), is a convenient tool to study enzyme dissociation (enolase), and provides arguments to understand the role of the partial volume of an enzyme (butyrylcholinesterase). This approach may have important implications for the understanding of the basic mechanism of protein diseases and for the development of preventive and therapeutic measures.


Assuntos
Pressão Hidrostática , Estrutura Terciária de Proteína , Ataxina-3 , Butirilcolinesterase/química , Humanos , Proteínas do Tecido Nervoso/química , Proteínas Nucleares , Fosfopiruvato Hidratase/química , Príons/química , Proteínas Repressoras , Termodinâmica
12.
Eur J Surg Oncol ; 41(10): 1361-7, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26263848

RESUMO

BACKGROUND: Over the last two decades, many surgical teams have developed programs to treat peritoneal carcinomatosis with extensive cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC). Currently, there are no specific recommendations for HIPEC procedures concerning environmental contamination risk management, personal protective equipment (PPE), or occupational health supervision. METHODS: A survey of the institutional practices among all French teams currently performing HIPEC procedures was carried out via the French network for the treatment of rare peritoneal malignancies (RENAPE). RESULTS: Thirty three surgical teams responded, 14 (42.4%) which reported more than 10 years of HIPEC experience. Some practices were widespread, such as using HIPEC machine approved by the European Community (100%), individualized or centralized smoke evacuation (81.8%), "open" abdominal coverage during perfusion (75.8%), and maintaining the same surgeon throughout the procedure (69.7%). Others were more heterogeneous, including laminar flow air circulation (54.5%) and the provision of safety protocols in the event of perfusate spills (51.5%). The use of specialized personal protective equipment is ubiquitous (93.9%) but widely variable between programs. CONCLUSION: Protocols regarding cytoreductive surgery/HIPEC and the associated professional risks in France lack standardization and should be established.


Assuntos
Ar Condicionado/métodos , Antineoplásicos/uso terapêutico , Carcinoma/terapia , Procedimentos Cirúrgicos de Citorredução/métodos , Hipertermia Induzida/métodos , Infusões Parenterais/métodos , Neoplasias Peritoneais/terapia , Equipamento de Proteção Individual/estatística & dados numéricos , Padrões de Prática Médica , França , Humanos , Saúde Ocupacional , Gestão de Riscos , Fumaça , Inquéritos e Questionários
13.
Protein Sci ; 10(4): 725-34, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11274463

RESUMO

FTIR spectroscopy was used to characterize and compare the temperature- and pressure-induced unfolding of ribonuclease A and a set of its variants engineered in a hydrophobic region of the C-terminal part of the molecule postulated as a CFIS. The results show for all the ribonucleases investigated, a cooperative, two-state, reversible unfolding transition using both pressure and temperature. The relative stabilities, among the different sites and different variants at the same site, monitored either through the changes in the position of the maximum of the amide I' band and the tyrosine band, or the maximum of the band assigned to the beta-sheet structure, corroborate the results of a previous study using fourth-derivative UV absorbance spectroscopy. In addition, variants at position 108 are the most critical for ribonuclease structure and stability. The V108G variant seems to present a greater conformational flexibility than the other variants. The pressure- and temperature-denaturated states of all the ribonucleases characterized retained some secondary structure. However, their spectral maxima were centered at different wavenumbers, which suggests that pressure- and temperature-denaturated states do not have the same structural characteristics. Nevertheless, there was close correlation between the pressure and temperature midpoint transition values for the whole series of protein variants, which indicated a common tendency of stability toward pressure and heat.


Assuntos
Estabilidade Enzimática/fisiologia , Engenharia de Proteínas/métodos , Dobramento de Proteína , Ribonuclease Pancreático/química , Substituição de Aminoácidos , Estabilidade Enzimática/genética , Pressão , Desnaturação Proteica/fisiologia , Espectroscopia de Infravermelho com Transformada de Fourier/instrumentação , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Temperatura
14.
Intensive Care Med ; 16(5): 303-6, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2212254

RESUMO

Gentamicin intrapatient pharmacokinetics variations were studied in 40 critically ill medical patients, suffering gram-negative sepsis. These patients were studied in two phases throughout gentamicin treatment: firstly, on the second day of treatment, when aggressive fluid therapy was required, and secondly, five days later, when patients had achieved a more stable clinical condition. Pharmacokinetic parameters were determined using least squares linear regression analysis assuming a one-compartment model using the Sawchuk-Zaske method. The apparent volume of distribution (Vd) in the first phase of the study was 0.43 +/- 0.12 L/kg, while on the seventh day of treatment it was 0.29 +/- 0.17 L/kg (p less than 0.001). Statistically significant differences were also observed for peak serum concentration (p less than 0.001), total dosage recommended (p less than 0.001) and half-life (p less than 0.05), whilst differences were not found for trough levels. From the analysis of the results obtained, we recommend increasing the initial dosage and monitoring plasma levels within the first days of therapy in critically ill patients treated with gentamicin, since important variations in aminoglycoside Vd related to disease, fluid balance and renal function, commonly occur in these patients.


Assuntos
Infecções Bacterianas/tratamento farmacológico , Cuidados Críticos , Gentamicinas/farmacocinética , Sepse/tratamento farmacológico , Adulto , Idoso , Infecções Bacterianas/microbiologia , Infecções Bacterianas/fisiopatologia , Peso Corporal , Espaço Extracelular , Feminino , Gentamicinas/administração & dosagem , Gentamicinas/uso terapêutico , Bactérias Gram-Negativas/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sepse/microbiologia , Sepse/fisiopatologia
15.
Breast ; 10(2): 149-54, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-14965576

RESUMO

Duct endoscopy is a recent technique used for a direct view of the breast ductal system. The aim of this study is to determine any morphological changes in breast tissue attributable to low-pressure irrigation with saline solution that the technique requires. A total of 26 breast biopsies from patients who underwent ductal endoscopy before surgery were compared with 26 breast specimens from the retroareolar region. Breast specimens from duct endoscopy showed more frequent epithelial detachment (73%), epithelial loss (35%), periductal clefts (77%), stromal disaggregation (46%) and displacement of epithelial cells into the stroma (27%) than the control group in which epithelial detachment was seen in 4% of patients, periductal clefts in 15%, and stromal disaggregation in 15%. Epithelial loss and epithelial displacement where not seen in the control group. Although low-pressure fluid perfusion used for duct endoscopy induced morphological changes in breast tissue, these can easily be distinguished from malignancy, and are most likely to occur as the result of duct rupture.

16.
J Environ Qual ; 30(5): 1829-35, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11577892

RESUMO

The growing concerns about water eutrophication have made it urgent to restrict losses of phosphorus (P) from agricultural soils and to develop methods for predicting such losses. In this work, we used the paradigm of P sorption-desorption curves to confirm the hypothesis that the amount of dissolved reactive phosphorus (DRP) released to a dilute electrolyte tends to be proportional to the concentration of DRP in the soil solution raised to a power that decreases with increasing solution to soil ratio (W). The hypothesis was tested for a group of 12 widely ranging European agricultural soils fertilized with P in excess of crop needs. Phosphorus desorption was studied under near-static and turbulent conditions in laboratory experiments. The concentration of DRP in the 1:1 soil to water extract (P1:1) was used as a proxy for the DRP concentration in the soil solution. The amount of desorbed P was found to be correlated with P1:1 raised to a power that decreased from 0.7 to 0.9 at W=100 to 0.2 to 0.4 at W=10 000. Correlation was not improved by introducing additional variables related to P sorption-desorption properties. Olsen P was found to be of lower predictive value than P1:1. Also, the index of degree of soil saturation with phosphorus (DSSP) based on oxalate extraction failed to predict P desorption. The fact that P1:1 seemingly predicts P desorption accurately for a wide range of soils makes it potentially useful in areas of high soil diversity.


Assuntos
Eutrofização , Modelos Teóricos , Fósforo/análise , Fósforo/química , Poluentes do Solo/análise , Absorção , Eletrólitos , Previsões
17.
J Anim Sci ; 71(9): 2539-45, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8407666

RESUMO

This study determined whether Cu and Zn balance was affected by feeding either Zn methionine (ZnMet) + Cu lysine (CuLys) or Zn sulfate (ZnSO4) + Cu sulfate (CuSO4) before and after stressing calves. Eight Charolais crossbred steer calves weighting 167 +/- 5 kg were randomly assigned to two treatments in a crossover experimental design. The millet hay and soybean meal diet when supplemented with the inorganic salts provided 9.2 ppm of Cu and 36.6 ppm of Zn or when fortified with the metal complexes contained 10.5 ppm of Cu and 36.6 ppm of Zn. Gentled calves were fed their respective diets for 28 d before an 18-d mineral balance trial was conducted. Collection consisted of five periods: 1) a 5-d baseline period, 2) 3 d of no Cu and Zn supplement, 3) 3 d of stress consisting of feed and water restriction and ACTH (80 IU) injections i.m. every 8 h, 4) 3 d of refeeding with no Cu and Zn supplement, and 5) 4 d of Cu and Zn repletion. Calves fed CuLys had 53% greater apparent Cu absorption and increased Cu retention (P < .05) during repletion compared with calves fed CuSO4. The 18-d mean retention of Cu from CuLys was greater (P < .05) than that from CuSO4. No differences (P > .05) in apparent absorption or retention of Zn were found between Zn sources, although during the 18-d trial mean retention was 58% higher when ZnMet was fed. Urinary Cu and Zn excretion decreased (P < .01) during stress.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Doenças dos Bovinos/metabolismo , Cobre/metabolismo , Estresse Fisiológico/veterinária , Zinco/metabolismo , Animais , Bovinos , Cobre/administração & dosagem , Cobre/sangue , Cobre/farmacocinética , Sulfato de Cobre , Hidrocortisona/sangue , Lisina/administração & dosagem , Lisina/farmacocinética , Masculino , Metionina/administração & dosagem , Metionina/análogos & derivados , Metionina/farmacocinética , Compostos Organometálicos/administração & dosagem , Compostos Organometálicos/farmacocinética , Distribuição Aleatória , Estresse Fisiológico/metabolismo , Sulfatos/administração & dosagem , Sulfatos/farmacocinética , Zinco/sangue , Compostos de Zinco/administração & dosagem , Compostos de Zinco/farmacocinética , Sulfato de Zinco
18.
J Anim Sci ; 73(4): 1208-12, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7628966

RESUMO

Our objective was to assess the consistency of representative digestion and energetics determinations used in animal nutrition. We used distribution theory of quadratic forms that allow for the attainment of width of confidence intervals (WI) for intraclass correlations. Three models commonly used in animal nutrition were analyzed, and their respective programs were coded to obtain the required confidence limits. Data sets were obtained from previous research published by our laboratory. Urinary, CH4, and ME were analyzed assuming a two-factor nested balanced variance component model. Rate of ruminal NDF disappearance (kd) and DM digestibility by an 8-d conventional collection trial were fitted to a two-factor crossed variance component model without interaction with a single observation per cell. Empty BW (EBW), carcass energy, and EBW energy were fitted to a two-factor crossed variance component model with interaction. Widths of confidence intervals varied with the example data set and variable tested. The narrowest WI was that of DM digestibility, less than .07 at a 95% confidence level for all the intraclass correlations, which shows the high consistency of the DM digestibility measurement in the specific study. Medium to large WI were found for kd and EBW; WI estimates were less than .70 at a 95% confidence level. Large WI, from .8 to 1.0 at a 95% confidence level, were found for the remaining variables, indicating the greater variability of these measurements. This methodology allows the assessment of the consistency of a measurement process and provides a method to monitor it each time a determination is made.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Digestão/fisiologia , Metabolismo Energético/fisiologia , Ruminantes/fisiologia , Análise de Variância , Animais , Simulação por Computador , Intervalos de Confiança , Fibras na Dieta/normas , Metano/urina , Modelos Biológicos , Reprodutibilidade dos Testes , Ruminantes/metabolismo
19.
J Anim Sci ; 72(3): 790-5, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8181998

RESUMO

Nutrient digestion and kinetic characteristics of alfalfa hay, brewers grains, beet pulp, and cottonseed hulls were studied in two experiments. In the first experiment, these feedstuffs were fed with a mineral/vitamin supplement in a 4 x 4 Latin square to eight ewes to determine total tract digestibilities by 8-d total collection and rates of passage using Yb as a marker. In the second experiment samples of the same feedstuffs were incubated in situ in four ruminally fistulated steers in a 4 x 4 Latin square design to quantify ruminal disappearance of NDF and ADF. Three Dacron bags were placed in the rumen for each of six time periods: 6, 12, 24, 48, 72, and 96 h. Total tract digestibilities of DM ranged from 33% for cottonseed hulls to 78% for beet pulp. Digestibilities of NDF ranged from 32% for cottonseed hulls to 81% for beet pulp. Total tract retention times ranged from 74 h for beet pulp to 44 h for alfalfa. Retention time for alfalfa was lower (P < .05) than those for beet pulp or cottonseed hulls. Calculation of TDN values yielded values similar to those of NRC other than for cottonseed hulls, for which NRC values were 18 to 29% higher. Alfalfa hay and beet pulp were the feedstuffs with the most rapidly disappearing NDF, .124/h for alfalfa and .116/h for beet pulp, which were faster (P < .05) than those found in brewers grains and cottonseed hulls, .035 and .043/h, respectively. Potentially digestible NDF ranged from 55% for alfalfa hay to 94% for beet pulp.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Ração Animal , Bovinos/fisiologia , Fibras na Dieta , Digestão , Ovinos/fisiologia , Ração Animal/análise , Animais , Ingestão de Energia , Feminino , Trânsito Gastrointestinal , Cinética , Masculino
20.
Methods Find Exp Clin Pharmacol ; 10(10): 663-6, 1988 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3236940

RESUMO

A simple way to study a histamine antagonist in man is to observe the effect it has on the magnitude of the skin reaction to intradermal histamine. The aim of the present study was to evaluate the antihistamine activity of single oral doses of 75 mg cinnarizine using 75 mg diphenhydramine as control, both being compared to placebo. The study was performed with two groups of 5 healthy subjects, each group receiving one of the active treatments or placebo randomly under blind conditions. All subjects received intradermal injections on the forearm of a 0.05 ml saline solution containing 5 micrograms of histamine before and at different times after drug intake. The histamine-induced wheal area was measured and, after drug administration, the percent decrease of the wheal area was calculated. Results showed that diphenhydramine produced a significant inhibition of the histamine-induced wheal size at 1.5 h which lasted up to 4 h after drug administration, reaching maximum inhibition at 2.5 h. After cinnarizine treatment no significant decrease of the histamine-induced wheal area was observed at any time.


Assuntos
Cinarizina/farmacologia , Antagonistas dos Receptores Histamínicos , Adulto , Cinarizina/administração & dosagem , Difenidramina/farmacologia , Humanos , Masculino , Testes Cutâneos , Fatores de Tempo
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