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1.
Tree Physiol ; 41(2): 254-268, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-32926137

RESUMO

Despite the economic importance of long-lived crop species in the Mediterranean Basin and their expansion to new warmer regions, their potential responses to prolonged temperature increases have not been adequately addressed. The objectives of this study were to: (i) assess leaf gas exchange responses to prolonged elevated temperature in young olive trees; (ii) evaluate some additional leaf traits such as stomatal density and size under these same conditions; and (iii) determine whether photosynthetic acclimation to temperature was apparent. A field experiment with two temperature levels was conducted using well-irrigated, potted olive trees (cvs. Arbequina, Coratina) grown in open-top chambers during the summer and early fall in two growing seasons. The temperature levels were a near-ambient control (T0) and a heated (T+) treatment (+4 °C). Maximum photosynthetic rate (Amax), stomatal conductance (gs), transpiration (E) and chlorophyll fluorescence were measured. Stomatal size and density and trichome density were also determined. The Amax, gs and chlorophyll fluorescence were little affected by heating. However, leaf E was higher at T+ than T0 in the summer in both seasons due in large part to the moderate increase in vapor pressure deficit that accompanied heating, and consequently water-use efficiency was reduced in heated leaves. When reciprocal temperature measurements were conducted in mid-summer of the second season, Amax values of T0 and T+ leaves were higher under the temperature level at which they grew than when measured at the other temperature level, which suggests some thermal acclimation. Stomatal size and density were greater in T+ than in T0 grown leaves in some cases, which was consistent with a greater E in T+ leaves when measured at both temperature levels. These results suggest that acclimation to long-term changes in temperature must be carefully considered to help determine how olive trees will be influenced by global warming.


Assuntos
Olea , Fotossíntese , Folhas de Planta , Temperatura , Árvores , Água
2.
Med. infant ; 25(1): 17-21, marzo 2018. tab
Artigo em Espanhol | LILACS | ID: biblio-883427

RESUMO

Introducción: La frecuencia de las candidemias ha aumentado en los últimos años asociada principalmente a internación prolongada, antibióticos de amplio espectro y enfermedades de base. Se produjo también un cambio en la distribución y un aumento en la resistencia a los antifúngicos de las distintas especies de Candida spp., todo esto asociado a una elevada morbimortalidad. En este trabajo realizado durante un año en un hospital de alta complejidad, se incluyeron 33 pacientes con candidemia. La mediana de la edad fue de 22 meses y un 60% de los afectados fueron varones. El 97% de los niños tenían enfermedad de base con predominio de la patología oncohematológica. Un 88% presentó algún procedimiento o condición predisponente para la infección, principalmente portación de catéter venoso central y cirugía previa. En un 59% de los aislamientos predominaron especies de Candida diferentes de Candida albicans. Anfotericina B desoxicolato fue el tratamiento empírico de elección. La mediana de tratamiento fue de 21 días y la de internación de 66 días. La mortalidad fue del 12% y se asoció a ingreso a UCI, presencia de fiebre al momento del diagnóstico y requerimiento de ARM (AU)


The incidence of candidemia has increased over the past years mainly associated with prolonged hospital stay, wide-spectrum antibiotics, and underlying diseases. At the same time there has been a change in the distribution and an increase in the resistance to antifungals in different Candida spp, associated with a high morbidity and mortality. In this study, conducted during one year at a tertiary hospital, 33 patients with candidemia were included. Median age was 22 months and 60% of the patients were boys. Overall, 97% of the children had an underlying hematology-oncology disease. Of the patients, 88% underwent a procedure or had a condition that predisposed to infection, mainly the placement of a central venous catheter and previous surgery. In 59% the isolated Candida species were Candida albicans. Amphotericin B deoxycholate was the empirical treatment of choice. Median time of treatment was 21 days and median hospital stay was 66 days. Mortality was 12% and was associated with ICU admission, presence of fever at the time of diagnosis, and requirement of mechanical ventilation (AU)


Assuntos
Humanos , Lactente , Pré-Escolar , Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Candida/efeitos dos fármacos , Candida/isolamento & purificação , Candidemia/epidemiologia , Candidemia/mortalidade , Criança Hospitalizada , Farmacorresistência Fúngica , Incidência , Estudo Observacional , Estudos Retrospectivos
3.
Med. infant ; 22(3): 210-213, Sept.2015.
Artigo em Espanhol | LILACS | ID: biblio-906583

RESUMO

Introducción: Fusarium spp. son hongos ubicuos que producen infecciones oportunistas en humanos incluyendo algunas severas en quemados. La literatura sobre infecciones por Fusarium spp. en pacientes quemados pediátricos es escasa. Objetivos: describir los hallazgos clínicos, epidemiológicos y evolutivos de infecciones por Fusarium spp. en pacientes quemados pediátricos. Pacientes y métodos: estudio retrospectivo, descriptivo de infecciones por Fusarium spp. en una unidad de cuidados intensivos pediátrica especializada entre enero de 2006 y marzo de 2015. Resultados: Quince pacientes presentaron infección por Fusarium spp. El 87% eran varones. La mediana de edad fue de 48 meses. En el 67% de los casos la quemadura fue por fuego directo. La superficie corporal quemada fue de una mediana de 45%. El 80% tuvo quemaduras profundas y el 93% presentó un índice de Garcés > 3. La infección fúngica se detectó con una mediana de 11 días desde la injuria. Todos los pacientes tuvieron catéteres centrales durante una mediana de 20 días y trece pacientes requirieron asistencia respiratoria mecánica durante una mediana de 16 días. En 14 pacientes el hongo fue aislado en la quemadura y en un paciente en el hueso. Trece pacientes tuvieron infecciones bacterianas concomitantes. Los antifúngicos de elección fueron anfotericina B y voriconazol. El tratamiento duró una mediana de 23 días. La mediana de internación fue de 55 días. Un solo paciente falleció debido a la infección fúngica. Conclusión: Fusarium spp. es un patógeno poco frecuente en pacientes quemados graves. La mortalidad fue baja (AU)


Introduction: Fusarium spp. are ubiquitous fungi recognized as opportunistic agents of human infections. They can produce severe infections in burn patients. The literature about Fusarium spp. infections in burn pediatric patients is scarce. Objectives: To describe clinical, epidemiological and outcome features of cases of Fusarium spp. infections in burn pediatric patients. Patients and Methods: Retrospective, descriptive study of Fusarium spp. infections in a specialized intensive care from January 2006 to March 2015. Results: 15 patients developed Fusarium spp infections. 87 % were male. Median age was 48 months. Direct fire injury was in ten patients. The affected burn surface was a median of 45%. Twelve patients had a full thickness burn. Fourteen patients had Garces Index>3. Fungal infection appears at a median of 11 days from injury. All patients had central lines during a median of 20 days and thirteen patients had mechanical ventilatory assistance for a median of sixteen days. Fungi vas isolated from burn wound in 14 patients and in bone in one patient. Thirteen patients had bacterial infection also. Amphotericin B was the drug of choice for treatment followed by voriconazole. Median time of complete treatment was 23 days. The median hospital stay was 55 days. One patient died of fungal infection related causes. Conclusion: Fusarium spp. is an uncommon pathogen in severely burn patients. Mortality was low (AU)


Assuntos
Humanos , Lactente , Pré-Escolar , Criança , Unidades de Queimados , Queimaduras/microbiologia , Fusariose/complicações , Fusariose/tratamento farmacológico , Fusarium/isolamento & purificação , Infecção dos Ferimentos/microbiologia , Antifúngicos/uso terapêutico , Estudo Observacional , Estudos Retrospectivos
4.
Mem. Inst. Invest. Cienc. Salud (Impr.) ; 12(2): 59-67, dic. 2014. tab
Artigo em Espanhol | LILACS, BDNPAR | ID: lil-736972

RESUMO

La hipertensión arterial es un factor de riesgo para el desarrollo de enfermedades cardiovasculares, principales causas de mortalidad en todo el mundo. El objetivo de este trabajo fue determinar la frecuencia de hipertensión arterial y su asociación con otros factores de riesgo cardiovascular en pacientes de primera consulta en el consultorio de la Primera Cátedra de Clínica Médica del Hospital de Clínicas, FCM, UNA en 2012. Se realizó un estudio observacional, descriptivo, retrospectivo, con componente analítico en el que se estudió a pacientes entre 18 y 90 años, seleccionados por muestreo aleatorio simple. En el periodo de estudio se registraron 4.046 historias clínicas en primera consulta, y 3.854 fueron consideradas para la aleatorización. Se estudiaron las variables demográficas, antropométricas, bioquímicas, presencia de hipertensión arterial, diabetes mellitus tipo 2, consumo de alcohol y tabaco. Se analizaron las historias clínicas de 457 pacientes con una edad media de 44,13±17 años; 48,23±18 años en hombres y 46,61±11 años en mujeres, 300 (66%) fueron mujeres. La frecuencia de la hipertensión arterial ± IC95% fue de 30,41±4,2%, sin diferencia significativa entre mujeres y hombres (32,33±4,3% versus 28±4,1%). La obesidad fue el factor de riesgo cardiovascular más frecuente. Alrededor del 60% de los pacientes presentaba uno o más factores de riesgo cardiovascular. La hipertensión arterial se asoció con la obesidad (OR: 4,427; IC95%: 2,345-4,876; p=0,032), la diabetes (OR: 2,141; IC 95%: 1,261-2,347; p=0,005) y niveles de c-HDL <35 mg/dl (OR: 1,761; IC 95%: 1,116-1,876; p= 0,001). Las altas frecuencias de hipertensión arterial y obesidad observadas en esta población coinciden con los datos reportados a nivel nacional y estuvo asociada significativamente a otros factores cardiovasculares.


Hypertension is a risk factor for the development of cardiovascular disease, the leadingcauses of mortality worldwide. The aim of this study was to determine the frequency ofhypertension and its association with other cardiovascular risk factors, in patients at theirfirst appointment in the Outpatient Careof Medical Clinic, Clinical Hospital, School ofMedicine, in 2012.An observational, descriptive, retrospective study with an analytical component was conducted, in which we studied patients aged 18 to 90 years, selected bysimple random sampling. In the study period, there were a total of 4,046 medical recordsin the first query, 3,854 met the inclusion criteriaand were considered for randomization.Demographic, anthropometric, biochemical variables, blood pressure, type 2 diabetesmellitus, alcohol and tobacco consumption were studied.The sample size was457medical recordswhichwere analyzed,the overall mean age was 44.13±17 years (men:48.23±18 years; women: 46.61±11 years), 300 patients (66%) were women. The overallfrequency ofhypertension (95% CI) was 30.41±4.2%, with no significant statisticaldifference (p=0.261) between women and men (32.33±4.3% versus 28±4.1%). Obesitywas the most frequent cardiovascularriskfactor. Almost 60% of patients had one ormore cardiovascular risk factors. Hypertension was associated with obesity (OR: 4.427,95% CI 2.345 to 4.876,p=0.032), diabetes (OR: 2.141, 95% CI: 1.261 to 2.347,p=0.005) and HDL-C<35 mg/dl (OR: 1.761, 95% CI: 1.116 to 1.876,p=0.001). The highfrequency of hypertension and obesity observed in this population are consistent withdata reported at the national level and was significantly associated with othercardiovascular factors.


Assuntos
Doenças Cardiovasculares , Hipertensão
7.
HIV Med ; 13(6): 367-71, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22252216

RESUMO

OBJECTIVES: Antiretroviral therapy (ART) medication prescribing errors in hospitalized patients still remain common. This study aimed to examine the initial prescribing of antiretroviral drug regimens for HIV clinic patients admitted to an urban academic teaching hospital. METHODS: A retrospective chart review of all patients with a discharge diagnosis of HIV or AIDS was performed. Only patients actively managed by the hospital out-patient HIV clinic at the time of discharge were included in the final analysis. We compared the ART initially prescribed during hospitalization with the clinic records. Medication errors were separated by type and the prescriber's area of specialty was noted. RESULTS: From 1 January 2009 to 31 December 2009, 90 admissions in 62 patients were included in the final analysis. In 47 of those admissions, the patient had an initial regimen considered to be incorrectly prescribed; in 17 of these 47 admissions, the patient was not prescribed any ART, and in the remainder the errors were related to drug omissions, incorrect frequency/dose, and prescription of the wrong drug. The majority of admissions were by an internal medicine or non-infectious disease (ID) specialist. Average time to ART initiation was comparable among all prescribers. No statistically significant correlation was found between the number of admissions per patient or the prescriber's area of specialty and the percentage of incorrect regimens ordered. CONCLUSION: Hospital HIV medication management still remains an area of focus because of the complexity of regimens, poor medication reconciliation and limited non-HIV/ID specialist knowledge.


Assuntos
Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Fármacos Anti-HIV/administração & dosagem , Erros de Medicação/estatística & dados numéricos , Síndrome da Imunodeficiência Adquirida/epidemiologia , Esquema de Medicação , Prescrições de Medicamentos , Feminino , Hospitalização , Humanos , Masculino , Prontuários Médicos , Pessoa de Meia-Idade , Estudos Retrospectivos , Estados Unidos/epidemiologia
8.
Protoplasma ; 231(3-4): 145-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17762907

RESUMO

Calcium oxalate crystals are by far the most prevalent and widely distributed mineral deposits in higher plants. In Tradescantia pallida, an evergreen perennial plant widely used as an ornamental plant, calcium oxalate crystals occur in the parenchymal tissues of stem, leaf, and root, as well as in flower organs, in the form of either raphides or tetragonal prismatic crystals or both. Energy-dispersive X-ray analysis revealed that C, O, and Ca were the main elements; and K, Cl, and Si, the minor elements. Infrared and X-ray analyses of crystals collected from these tissues detected the coexistence of two calcium oxalate chemical forms, i.e., whewellite and weddellite, as well as calcite, opal, and sylvite. Here, we show for the first time the occurrence of epitaxy in mineral crystals of plants. Epitaxy, which involves the oriented overgrowth of one crystal onto a second crystalline substrate, might explain how potassium chloride (sylvite)--one of the most water-soluble salts--stays insoluble in crystal form when coated with a calcium oxalate epilayer. The results indicate the potential role of crystals in regulating the ionic equilibrium of both calcium and potassium ions.


Assuntos
Cloreto de Potássio/química , Tradescantia/química , Cálcio/metabolismo , Oxalato de Cálcio/química , Cristalização , Raios Infravermelhos , Microscopia Eletrônica de Varredura , Potássio/metabolismo , Tradescantia/metabolismo , Tradescantia/ultraestrutura , Difração de Raios X
9.
Int J Food Microbiol ; 87(1-2): 187-92, 2003 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-12927722

RESUMO

Lactobacillus manihotivorans has been reported as one of the dominant species in cassava sour starch production process. Seven isolates that have previously been identified as belonging to this species were studied in the present work. Their molecular and phenotypic characteristics showed higher strain diversity than previously described. Differences were found in their fermentation profiles, whereas no major differences were observed in properties related to processing conditions (salt concentration, pH, temperature), or in potential functional properties (bile salt and pH 2.0 tolerance). Among the main characteristics of interest for the fermentation of cereals or cassava, blended or not with legumes, six out of seven strains were amylolytic and raffinose was fermented by all strains. Strains OND 32T and OLB 7 fermented the broadest range of carbohydrates. Most of the strains contained plasmids. Plasmid curing changed their phenotypic characteristics, particularly those of strain OND 32T, which, in addition, lost its starch and raffinose fermentation ability.


Assuntos
Microbiologia de Alimentos , Lactobacillus/classificação , Manihot/microbiologia , Amido/química , Fermentação , Concentração de Íons de Hidrogênio , Ácido Láctico/metabolismo , Lactobacillus/isolamento & purificação , Filogenia , Amido/metabolismo , Temperatura
10.
J Mater Sci Mater Med ; 13(12): 1129-33, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15348654

RESUMO

DLC (diamond-like carbon) coatings have remarkable tribological properties due mainly to their good frictional behavior. These coatings can be applied in many industrial and biomedical applications, where sliding can generate wear and frictional forces on the components, such as orthopaedic metal implants. This work reports on the development and tribological characterization of functionally gradient titanium alloyed DLC coatings. A PVD-magnetron sputtering technique has been used as the deposition method. The aim of this work was to study the tribological performance of the DLC coating when metal to metal contact (cobalt chromium or titanium alloys) takes place under dry and lubricated test conditions. Prior work by the authors demonstrates that the DLC coating reduced considerably the wear of the ultra-high-molecular-weight polyethylene (UHMWPE). The DLC coating during mechanical testing exhibited a high elastic recovery (65%) compared to the values obtained from Co-Cr-Mo (15%) and Ti-6Al-4V (23%). The coating exhibited an excellent tribo-performance against the Ti-6Al-4V and Co-Cr-Mo alloys, especially under dry conditions presenting a friction value of 0.12 and almost negligible wear. This coating has passed biocompatibility tests for implant devices on tissue/bone contact according to international standards (ISO 10993).

11.
Rev Iberoam Micol ; 15(2): 69-74, 1998 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-17655412

RESUMO

The area of natural products research is the most rapidly growing field of organic chemistry, due to the great technical developments in the isolation and identification techniques. Today, near to one million natural products -isolated from the most diverse living things- are known. Microorganisms are among the least-studied of these. Nevertheless, they offer large possibilities for the discovery of new structures and biological activities. Among the microorganisms, the Basidiomycetes present a production capacity and a range of biologically active metabolites, which have scarcely been investigated. The wide spectrum of natural products with biological activity produced by Basidiomycetes includes antimicrobial agents, antifungal, antiviral and cytotoxic activities, enzymes, plant growth regulators and flavors. These metabolites are generally grouped by their chemical origin, and the relationship between chemical structure and the different biological activities reported. The main objective of this review is to bring an updated revision of the numerous and interesting biosynthetic pathways from basidiomycetes.

12.
Appl Environ Microbiol ; 63(7): 2637-46, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9212414

RESUMO

A new lignin-degrading basidiomycete, strain I-62 (CECT 20197), isolated from decayed wood exhibited both a high dephenolization activity and decolorization capacity when tested on effluents from the sugar cane by-product fermentation industry. It has been classified as a member of the Polyporaceae family. The major ligninolytic activity detected in culture supernatants of basidiomycete I-62 was a phenoloxidase (laccase), in conjunction with small amounts of manganese peroxidase. No lignin peroxidase was detected. Laccase activity was produced in either defined or complete media. Addition of veratryl alcohol as the inducer, in defined medium, enhanced laccase production 10-fold. The use of fructose instead of glucose as a carbon source resulted in a 100-fold increase in laccase specific activity. Native isoelectrofocusing gels stained with guaiacol revealed the presence of at least seven laccase isozymes, with the most intense band being detected at pI 3. Southern hybridization analysis indicated the presence of a laccase gene family in strain I-62. Three different genes coding for phenoloxidases, lcc1, lcc2, and lcc3, were cloned and characterized. The high degree of homology between laccases from strain I-62 and laccases from Trametes species suggests a phylogenetic proximity between this new isolated fungus and the genus Trametes.


Assuntos
Basidiomycota/enzimologia , Basidiomycota/genética , Oxirredutases/genética , Oxirredutases/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Álcoois Benzílicos/metabolismo , Clonagem Molecular , Meios de Cultura/metabolismo , Frutose/metabolismo , Glucose/metabolismo , Focalização Isoelétrica , Isoenzimas/isolamento & purificação , Lacase , Lignina/metabolismo , Dados de Sequência Molecular , Oxirredutases/química , Peroxidases/metabolismo , Filogenia , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos
13.
Bull Pan Am Health Organ ; 29(4): 338-51, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8605525

RESUMO

A study was made of the feeding history from birth to 1 month of age in a cohort of children born and residing in the city of Córdoba, Argentina, in 1993. The sample was divided into six social strata, in accordance with the occupation of the individual primarily responsible for family support. A total of 620 mothers were surveyed 1 month (mean = 31 days; SD = 1.2 days) following delivery in order to obtain information on the occupational, housing, and demographic characteristics of the family. In addition, information was collected on the first food given to infants following birth as well as on the type of food received at 1 month of age, the latter being based on 24-hour recall. The living conditions and demographic characteristics of the families were associated with their social strata. Families in Stratum I (high) and strata II and III (intermediate) tended to have higher standards of living and to have parents who were older when the children were born than did families in the lowest strata (V and VI), while families in Stratum IV tended to approach the average values found for the entire sample. With regard to feeding practices, it was found that 98% of the children had begun breast-feeding during the first week of life. A statistical association was observed between first food and social strata, with breast-feeding being more prevalent among the very low strata (V and VI) and use of bottle feeding being more prevalent in strata I and III. At 1 month of age, 26% of the sample was receiving complete natural breast-feeding, 60% was receiving partial natural breast-feeding, and 14% was being entirely bottle-fed. A significant association (P < 0.05) was observed between type of breast-feeding and social strata, with a figure of 38% complete natural breast-feeding recorded for Stratum I as compared to 16% for Stratum IV and 17% for Stratum V. Other findings of this study that stood out were that a high percentage of children in all the strata were initially breast-fed; a high percentage of the children were given breast-milk substitutes during the first month of life; and a low prevalence of complete natural breast-feeding was observed at 1 month of age.


Assuntos
Alimentação com Mamadeira/estatística & dados numéricos , Aleitamento Materno/etnologia , Comportamento Alimentar/etnologia , Classe Social , Adulto , Argentina , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Prevalência , Estudos Prospectivos , Inquéritos e Questionários
14.
Oecologia ; 80(2): 268-271, 1989 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28313118

RESUMO

Morphologically distinct populations of a North American perennial grass, Agropyron smithii, collected from a heavily grazed prairie dog (Cynomys ludovicianus) colony (PDC) and a grazing exclosure (EX), were grown in an environmental chamber to determine whether: (1) leaf silicon (Si) concentrations are greater in plant populations which differentiated under heavy grazing pressure, and (2) leaf silicification is inducible by defoliation. Mean shoot Si concentration of nondefoliated plants was greater in the PDC population (2.2%) than the EX population (1.9%) over the 18 wk experiment, largely as a result of differences in Si concentrations in leaf blades. However, leaf Si concentration was lower in defoliated plants of each population than in nondefoliated plants, indicating that leaf silicification was not an inducible herbivore defense mechanism in A. smithii. The higher leaf Si concentrations from the heavily grazed population may be associated with grazingrelated environmental stresses such as a warmer, drier microclimate or with morphological characteristics related to grazing tolerance or avoidance.

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