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1.
Plant Biol (Stuttg) ; 25(5): 740-749, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37158679

RESUMEN

Aluminium (Al) is toxic to most plants. Nevertheless, some species accumulate Al without showing toxicity symptoms. Previous studies have evidenced Al in chloroplasts of Al-accumulating species from the Cerrado vegetation in South America. We ask whether Al increases carbon assimilation through enhanced apparent efficiency of Rubisco. Seedlings of the Al-accumulator Qualea grandiflora (Vochysiaceae) were grown in nutrient solution with 0, 740, and 1480 µm Al. Growth parameters, relative leaf water content, Al concentration in organs, gas exchange and apparent carboxylation efficiency (measured from A/Ci curves) were evaluated for 60 days. Plants without Al showed no root growth, necrotic roots, low gas exchange rates, and decreased apparent carboxylation efficiency. Al-treated plants, however, showed new white roots and increased root biomass leading to higher leaf hydration, and apparent carboxylation efficiency was higher in these plants. Increased Al available in the nutrient solution increased Al accumulation in plant organs. Absence of Al compromised root integrity in Q. grandiflora, thus limiting leaf hydration. No positive direct effect of Al on Rubisco was evidenced in Al-treated plants.


Asunto(s)
Aluminio , Myrtales , Aluminio/toxicidad , Ribulosa-Bifosfato Carboxilasa , Plantas , Plantones , Hojas de la Planta , Raíces de Plantas
2.
Braz J Med Biol Res ; 54(9): e10928, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34133538

RESUMEN

This study aimed to evaluate the frequency of cryptic Candida species from candidemia cases in 22 public hospitals in São Paulo State, Brazil, and their antifungal susceptibility profiles. During 2017 and 2018, 144 isolates were molecularly identified as 14 species; C. parapsilosis (32.6%), C. albicans (27.7%), C. tropicalis (14.6%), C. glabrata (9.7%), C. krusei (2.8%), C. orthopsilosis (2.8%), C. haemulonii var. vulnera (2.1%), C. haemulonii (1.4%), C. metapsilosis (1.4%), C. dubliniensis (1.4%), C. guilliermondii (1.4%), C. duobushaemulonii (0.7%), C. kefyr (0.7%), and C. pelliculosa (0.7%). Poor susceptibility to fluconazole was identified in 6.4% of C. parapsilosis isolates (0.12 to >64 µg/mL), 50% of C. guilliermondii (64 µg/mL), 66.6% of C. haemulonii var. vulnera (16-32 µg/mL), and C. duobushaemulonii strain (MIC 64 µg/mL). Our results corroborated the emergence of C. glabrata in Brazilian cases of candidemia as previously reported. Importantly, we observed a large proportion of non-wild type C. glabrata isolates to voriconazole (28.6%; <0.015 to 4 µg/mL) all of which were also resistant to fluconazole (28.6%). Of note, C. haemulonii, a multidrug resistant species, has emerged in the Southeast region of Brazil. Our findings suggested a possible epidemiologic change in the region with an increase in fluconazole-resistant species causing candidemia. We stress the relevance of routine accurate identification to properly manage therapy and monitor epidemiologic trends.


Asunto(s)
Antifúngicos , Candida , Antifúngicos/farmacología , Brasil , Farmacorresistencia Fúngica , Hospitales , Pruebas de Sensibilidad Microbiana
3.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;54(9): e10928, 2021. graf
Artículo en Inglés | LILACS | ID: biblio-1278587

RESUMEN

This study aimed to evaluate the frequency of cryptic Candida species from candidemia cases in 22 public hospitals in São Paulo State, Brazil, and their antifungal susceptibility profiles. During 2017 and 2018, 144 isolates were molecularly identified as 14 species; C. parapsilosis (32.6%), C. albicans (27.7%), C. tropicalis (14.6%), C. glabrata (9.7%), C. krusei (2.8%), C. orthopsilosis (2.8%), C. haemulonii var. vulnera (2.1%), C. haemulonii (1.4%), C. metapsilosis (1.4%), C. dubliniensis (1.4%), C. guilliermondii (1.4%), C. duobushaemulonii (0.7%), C. kefyr (0.7%), and C. pelliculosa (0.7%). Poor susceptibility to fluconazole was identified in 6.4% of C. parapsilosis isolates (0.12 to >64 µg/mL), 50% of C. guilliermondii (64 µg/mL), 66.6% of C. haemulonii var. vulnera (16-32 µg/mL), and C. duobushaemulonii strain (MIC 64 µg/mL). Our results corroborated the emergence of C. glabrata in Brazilian cases of candidemia as previously reported. Importantly, we observed a large proportion of non-wild type C. glabrata isolates to voriconazole (28.6%; <0.015 to 4 µg/mL) all of which were also resistant to fluconazole (28.6%). Of note, C. haemulonii, a multidrug resistant species, has emerged in the Southeast region of Brazil. Our findings suggested a possible epidemiologic change in the region with an increase in fluconazole-resistant species causing candidemia. We stress the relevance of routine accurate identification to properly manage therapy and monitor epidemiologic trends.


Asunto(s)
Candida , Antifúngicos/farmacología , Brasil , Pruebas de Sensibilidad Microbiana , Farmacorresistencia Fúngica , Hospitales
4.
Pak J Biol Sci ; 10(4): 568-74, 2007 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-19069536

RESUMEN

The present research evaluated the influence of a chayotte (Sechium edule) extract (macerated) on the bioavailability of 99TcO4Na as well as in the mass of the organs. In this study, in the biodistribution analysis, the 99mTcO4Na was administrated into female Wistar rats (diabetes and no diabetes induced) which had drunk or not the extract for 7 days. After 10 min, animals were sacrificed, the organs were isolated, the radioactivity determined in a well counter and the percentages of radioactivity per gram (%ATI/g) in the organs and mass of them (g) were calculated. The analysis of the results has indicated that in the diabetes group had been an increase in the uptake of 99mTcO4Na the in pancreas as well as in the diabetes groups treated with chayotte extract. The mass of the spleen, stomach, pancreas, heart and kidney has been altered due to the comparison of the groups. It is possible to suggest that some components of chayotte extracts present an oxidant power able to alter the biodistribution of 99mTcO4Na, as a tip, we speculate that the referred extract when metabolized in the liver may produce reactive metabolites with oxidant properties linked to the stress which is generated by diabetic status, this fact could justify by the increase of %ATI/g in the pancreas which probably may be due to the producing of AGEs in diabetes status as well as by the different molecular and cellular mechanisms related to the effects of the extract and diabetes would promote differences in the mass of the organs.


Asunto(s)
Cucurbitaceae/química , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Experimental/radioterapia , Extractos Vegetales/química , Extractos Vegetales/uso terapéutico , Radiofármacos/uso terapéutico , Animales , Diabetes Mellitus Experimental/inducido químicamente , Tamaño de los Órganos/efectos de los fármacos , Extractos Vegetales/farmacocinética , Radiofármacos/farmacocinética , Ratas , Ratas Wistar
5.
Pak J Biol Sci ; 10(5): 823-7, 2007 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-19069873

RESUMEN

The use of natural products as medicines has been growing in the entire world. There are concerns that these products may contain potentially toxic ingredients and contaminants such as heavy metals. The labeling of blood constituents with technetium-99m has been influenced by the presence of natural extracts. We evaluated the influence of a chayotte (Sechium edule) extract (100% v/v macerated) on the labeling of blood elements with 99mTc. The animals were treated with the extract during 15 days. Samples of blood were carried out with specific blood biochemistry kits. The present study analyzed the influence ofchayotte in the survival of the strain of Escherichia coli AB1157 submitted to reactive oxygen species induced by stannous chloride. There was a reduction of the lethal effect induced by stannous chloride on the survival of the E. coli culture in the presence of chayotte. The results indicated a decrease in the level of glucose and globulin The effect of the extract could be explained by its metabolic transformation inducing the generation of oxidant metabolites. The culture of bacteria when was treated with stannous chloride and chayotte simultaneously, the extract could be reacting with stannous chloride ions, protecting them against the oxidation avoiding the generation of reactive oxygen species.


Asunto(s)
Análisis Químico de la Sangre , Cucurbitaceae/química , Extractos Vegetales/farmacología , Compuestos de Estaño/farmacología , Animales , Ratas , Ratas Wistar
6.
Waste Manag ; 25(1): 67-74, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15681180

RESUMEN

The progress of the technology is directly related to the growth of production and consumption of electrical/electronics equipment, especially of personal computers. This type of equipment has a relatively short average lifetime, 2-3 years. The amount of defective or obsolete equipment has been increasing substantially; consequently its disposition and/or recycling should be studied. In this work, printed circuit boards, which are used in personal computers, were studied in order to recover the metals in the circuit boards through mechanical processing, such as crushing, screening, as well as magnetic and electrostatic separation. The results obtained demonstrate the feasibility of using these processes to separate metal fractions from polymers and ceramics, and that it is possible to obtain a fraction concentrated in metals containing more than 50% on average of copper, 24% of tin and 8% of lead.


Asunto(s)
Conservación de los Recursos Naturales , Electrónica , Metales/aislamiento & purificación , Microcomputadores , Administración de Residuos/métodos , Cerámica , Magnetismo , Polímeros , Electricidad Estática
7.
J Control Release ; 92(1-2): 103-12, 2003 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-14499189

RESUMEN

This study describes new lectin-decorated or protein-loaded nanoparticles with a hydrophobic poly(epsilon-caprolactone) (PCL) core and a hydrophilic dextran (Dex) corona. In this view, a family of block Dex-PCLn copolymers was first synthesized, consisting of a Dex backbone to which n preformed PCL blocks were grafted. The ability of these new copolymers to form nanoparticles was evaluated in comparison with a series of PCL homopolymers of various molecular weights (2000, 10,000 and 40,000 g/mole). Two different nanoparticle preparation methods have been developed and tested for their efficacy to incorporate proteins. For this, three proteins were used: a model protein, bovine serum albumin (BSA), a lectin from leaves of Bauhinia monandra (BmoLL) and Lens culinaris (LC) lectin. All these proteins were successfully incorporated in nanoparticles with a mean diameter around 200 nm. Lectins could also be adsorbed onto the surface of Dex-PCLn nanoparticles. Surface-bound BmoLL conserved its hemagglutinating activity, suggesting the possible application of this type of surface-modified nanoparticles for targeted oral administration. Caco-2 cellular viability was higher than 70% when put in contact with Dex-PCLn nanoparticles, even at concentrations as high as 660 microg/ml.


Asunto(s)
Nanotecnología/métodos , Lectinas de Plantas/farmacocinética , Poliésteres/farmacocinética , Polisacáridos/farmacocinética , Albúmina Sérica Bovina/farmacocinética , Animales , Células CACO-2 , Bovinos , Humanos , Hojas de la Planta , Lectinas de Plantas/química , Poliésteres/química , Polisacáridos/química , Albúmina Sérica Bovina/química , Propiedades de Superficie/efectos de los fármacos
8.
Arq Gastroenterol ; 19(3): 113-9, 1982.
Artículo en Portugués | MEDLINE | ID: mdl-6764358

RESUMEN

The authors have reviewed the anastomosis and sutures utilized for the surgical treatment of 38 patients with carcinoma of the esophagus and cardia. They have compared results following the stapled anastomosis and sutures with those following hand sutured procedures (30 anastomosis and 13 sutures) performed by the same group of surgeons. The stapled anastomosis were performed utilizing a new circular stapling device and gastric and jejunal stapled sutures, utilizing Nakayama's clamp. When anastomosis and sutures were performed by hand suturing, standard techniques were utilized. Patients were grouped in three categories: Group I if the gastric or jejunal sutures or the esophagogastric or esophagojejunal anastomosis were hand sutured; Group II wherein both stapled and hand sutures were performed; Group III when the esophageal anastomosis and related sutures were all performed by stapling devices. Different factors with possible adverse effect on suture healing were also studied. The incidence of suture related complications ranged between 4,2 and 29,1% for Group I; 1,8 and 19,2% for Group II; 0 and 16,2% for Group III. The 60-day operative mortality rate was 23% for Group I (8,4-50,9%), 17,64% for Group II (6,4-25,9%) and 0% (0-28,3%) for Group III. It is felt that better results were obtained with stapled sutures.


Asunto(s)
Neoplasias Esofágicas/cirugía , Engrapadoras Quirúrgicas , Técnicas de Sutura , Humanos , Complicaciones Posoperatorias , Cicatrización de Heridas
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