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1.
J Periodontal Res ; 51(5): 661-8, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26740292

RESUMO

BACKGROUND AND OBJECTIVE: LP533401 is an inhibitor of tryptophan hydroxylase 1, which regulates serotonin production in the gut. Previous work indicates that LP533401 has an anabolic effect in bone. Thus, we hypothesized that inhibition of gut serotonin production may modulate the host response in periodontal disease. In this study, we aimed to analyze the effects of LP533401 in a rat periodontitis model to evaluate the role of gut serotonin in periodontitis pathophysiology. MATERIAL AND METHODS: Twenty-four rats were divided into three groups: treated group (T: ligature-induced periodontal disease and LP533401, 25 mg/kg/d) by gavage; ligature group (L: ligature-induced periodontal disease only); and control group (C: without ligature-induced periodontal disease). After 28 d, radiographic alveolar bone support was measured on digital radiographs, and alveolar bone volume fraction, tissue mineral density and trabeculae characteristics were quantified by microcomputed tomography in the right hemi-mandible. Left hemi-mandibles were decalcified and alveolar bone loss, attachment loss and area of collagen in the gingiva were histologically analyzed. RESULTS: Significant difference between the L and C groups was found, confirming that periodontal disease was induced. We observed no difference between the T and L groups regarding alveolar bone destruction and area of collagen. CONCLUSION: LP533401 (25 mg/kg/d) for 28 d does not prevent bone loss and does not modulate host response in a rat model of induced periodontal disease.


Assuntos
Doenças Periodontais/tratamento farmacológico , Doenças Periodontais/patologia , Pirimidinas/antagonistas & inibidores , Serotonina/metabolismo , Perda do Osso Alveolar/diagnóstico por imagem , Perda do Osso Alveolar/tratamento farmacológico , Perda do Osso Alveolar/patologia , Perda do Osso Alveolar/prevenção & controle , Animais , Colágeno , Modelos Animais de Doenças , Gengiva/patologia , Ligadura/efeitos adversos , Masculino , Mandíbula/patologia , Perda da Inserção Periodontal/diagnóstico por imagem , Perda da Inserção Periodontal/prevenção & controle , Periodontite/tratamento farmacológico , Periodontite/patologia , Ratos , Ratos Wistar , Serotonina/fisiologia , Microtomografia por Raio-X/métodos
2.
Heliyon ; 9(4): e14922, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37089371

RESUMO

Deep-renovations measures are identified as possible solutions to support European Union's natural gas phase-out and fuel independency. However, it has been difficult to increase renovation rates (about 1% per year), and previous studies have recognized socio-economic barriers as one of the reasons for that. Then, integrated (techno-socio-economic) datasets are vital to support building policy measures that circumvent the negative consequences of high gas prices. This paper's main objective is to develop and to test a methodology that merges two data sources: the European Union Statistics on Income and Living Conditions and the Household Budget Survey in order to create an integrated techno-socio-economic dataset. The following research questions are answered: What is the replicable methodology for merging both datasets in order to create an accurate statistical model? What can we learn about household savings and natural gas expenditures of household types characterised by ownership status and dwelling type? The modelling results show that the developed logistic regression model presented an accuracy of 77% using 2015 data from Spain. The explorative statistical analysis showed that the owner-occupied single-family houses predominate in the highest natural gas expenditure quintiles, while the rented single-family houses in the lowest quintiles, indicating that ownership status may have a stronger influence on the natural gas expenditure than building type. The mean annual household savings are negative, an evidence of households' budget restrictions to finance deep renovation activities. As a conclusion, the generated techno-socio-economic synthetic dataset provides useful information about the relation between household budget restrictions, natural gas expenditure and potential investment on deep renovation. Based on the generated dataset, it is also concluded that higher natural gas prices alone are not sufficient to stimulate deep renovations. For boosting renovation activities, the design of financing and incentive schemes should be end-user targeted considering the households' heterogeneity. Then, the definition of households' profiles should include ownership status and other socio-economic parameters not only dwelling type. This work prepares the ground for setting techno-socio-economic databases that can be used to design more accurate incentives and financing schemes to accelerate European building stock decarbonisation and fossil fuel independency.

4.
Environ Pollut ; 147(3): 691-5, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17116349

RESUMO

Psidium guajava 'Paluma' saplings were exposed to carbon filtered air (CF), ambient non-filtered air (NF), and ambient non-filtered air+40ppb ozone (NF+O(3)) 8h per day during two months. The AOT40 values at the end of the experiment were 48, 910 and 12 895ppbh(-1), respectively for the three treatments. After 5 days of exposure (AOT40=1497ppbh(-1)), interveinal red stippling appeared in plants in the NF+O(3) chamber. In the NF chamber, symptoms were observed only after 40 days of exposure (AOT40=880ppbh(-1)). After 60 days, injured leaves per plant corresponded to 86% in NF+O(3) and 25% in the NF treatment, and the average leaf area injured was 45% in NF+O(3) and 5% in the NF treatment. The extent of leaf area injured (leaf injury index) was explained mainly by the accumulated exposure of ozone (r(2)=0.91; p<0.05).


Assuntos
Oxidantes Fotoquímicos/análise , Ozônio/análise , Psidium/química , Brasil , Exposição Ambiental/efeitos adversos , Monitoramento Ambiental/métodos , Folhas de Planta/química , Folhas de Planta/efeitos dos fármacos , Psidium/efeitos dos fármacos , Clima Tropical
5.
Chemosphere ; 66(7): 1310-4, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16930673

RESUMO

Psidium guajava 'Paluma' was evaluated under field conditions as a tropical bioindicator species of ozone (O(3)). Three exposures of 90 days each were performed (June 21, 2004-March 19, 2005). In each one of them, saplings of 'Paluma' (n=30) were exposed to ambient air at a site in São Paulo (Brazil) with high ozone concentrations, and in a greenhouse with charcoal-filtered air. Ozone-like visible foliar injuries were observed during the winter, spring and summer exposures, when AOT40 reached 6166ppbh, 3504ppbh and 4828ppbh, respectively. No injuries were observed in the plants kept under filtered air. The injuries consisted in red stippling on adaxial leaf surfaces. They did not cover the veins and appeared first in older leaves, becoming more intense as the exposure period increased. Injury incidence, severity, and the cumulative exposure threshold at injury onset varied among the exposure periods. AOT40 explained partly the incidence, severity and leaf injury index LII (r(2)=0.52, 0.39, 0.38, respectively, p=0.002). The results confirm the potential of the species as an O(3)-sensitive bioindicator.


Assuntos
Poluentes Atmosféricos/toxicidade , Monitoramento Ambiental/métodos , Ozônio/toxicidade , Psidium/efeitos dos fármacos , Brasil , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Psidium/crescimento & desenvolvimento
6.
Phytochemistry ; 54(2): 115-20, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10872202

RESUMO

Podophyllin, an ethanolic extract of Podophyllum peltatum L. or P. emodi Wall (syn. P. hexandnum Royle), is a good source of the aryltetralin-type lignan, podophyllotoxin. The latter compound, as well as its congeners and derivatives exhibit pronounced biological activity mainly as strong antiviral agents and as antineoplastic drugs. The podophyllotoxin derivatives etoposide, etopophos (etoposide phosphate), and teniposide are thus successfully utilized in the treatment of a variety of malignant conditions. Continued research on the Podophyllum lignans is currently focused on structure optimization to generate derivatives with superior pharmacological profiles and broader therapeutic scope, and the development of alternative and renewable sources of podophyllotoxin.


Assuntos
Podofilotoxina/farmacologia , Podofilotoxina/síntese química , Podofilotoxina/química
7.
Environ Int ; 28(5): 367-74, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12437286

RESUMO

Psidium guajava L., Psidium cattleyanum Sabine and Mangifera indica L. were tested under field conditions as possible tropical bioindicators of industrial air pollution. The study was performed around the industrial complex of Cubatão, SE Brazil, which comprises 23 industries, including fertilizer, cement, chemical, petrochemical, and steel plants, with 110 production units and 260 emission sources of pollutants. Saplings were exposed to environmental conditions during four periods of 16 weeks each (September 1994-September 1995), at four different sites in the coastal mountains near the industrial complex: the Valley of Pilões River (VP), the reference area; the Valley of Mogi River (VM), with high contamination of particulate matter, fluorides (F), sulfur (S) and nitrogen (N) compounds; Caminho do Mar (CM1, CM2), mainly affected by organic pollutants, S and N compounds, and secondary pollutants; and Paranapiacaba (PP), affected by secondary pollutants, such as ozone. M. indica did not adapt to the climatic conditions at the exposure sites. In the two Psidium species, the presence of visible symptoms, root/shoot ratio, foliar contents of F, S and N, amounts of ascorbate (AA) and water-soluble thiols (-SH), as well as peroxidase activity (POD) were determined. P. guajava showed higher foliar accumulation of F, S and N, more pronounced alterations of biochemical indicators, and less visible leaf injury than P. cattleyanum. P. guajava may be used as an accumulative indicator in tropical climates, while further studies will be needed before P. cattleyanum might be applied as a sensitive species in biomonitoring programs.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Monitoramento Ambiental/métodos , Mangifera , Psidium , Poluentes Atmosféricos/análise , Brasil , Indústrias , Mangifera/fisiologia , Folhas de Planta/química , Psidium/fisiologia , Sensibilidade e Especificidade , Clima Tropical
8.
Environ Sci Pollut Res Int ; 21(17): 10514-24, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24781331

RESUMO

Brazilian soybean cultivars (Glycine max Sambaíba and Tracajá) routinely grown in Amazonian areas were exposed to filtered air (FA) and filtered air enriched with ozone (40 and 80 ppb, 6 h/day for 5 days) to assess their level of tolerance to this pollutant by measuring changes in key biochemical, physiological, and morphological indicators of injury and in enzymatic and non-enzymatic antioxidants. Sambaíba plants were more sensitive to ozone than Tracajá plants, as revealed by comparing indicator injury responses and antioxidant stimulations. Sambaíba exhibited higher visible leaf injury, higher stomatal conductance, and a severe decrease in the carbon assimilation rate. Higher ozone level (80 ppb) caused an increase in cell death in both cultivars. Levels of malondialdehyde and hydrogen peroxide also increased in Tracajá exposed under 80 ppb. Sambaíba plants exhibited decreases in ascorbate and glutathione levels and in enzymatic activities associated with these antioxidants. The higher tolerance of the Tracajá soybean appeared to be indicated by reduced physiological injuries and lower stomatal conductance, which might decrease the influx of ozone and enhance oxidation-reduction reactions involving catalase, ascorbate peroxidase, ascorbate, and glutathione, most likely stimulated by higher hydrogen peroxide.


Assuntos
Agricultura/métodos , Poluentes Atmosféricos/efeitos adversos , Glycine max/efeitos dos fármacos , Glycine max/fisiologia , Ozônio/efeitos adversos , Análise de Variância , Antioxidantes/metabolismo , Ácido Ascórbico/metabolismo , Brasil , Morte Celular/efeitos dos fármacos , Eletroforese em Gel de Poliacrilamida , Peróxido de Hidrogênio/metabolismo , Peroxidação de Lipídeos , Oxirredução , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Estômatos de Plantas/efeitos dos fármacos , Glycine max/metabolismo , Especificidade da Espécie , Superóxido Dismutase/metabolismo
9.
Immunopharmacol Immunotoxicol ; 23(1): 83-95, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11322652

RESUMO

There exists a growing body of research which indicates that antimitotics such as taxol and colchicine influence cytokine gene expression. In the present study we examined the effect of podophyllotoxin and six analogs on nuclear factor kappa B (NF-kappa B) activation, and on interleukin-1 beta (IL-1beta) and tumor necrosis factor alpha (TNF-alpha) mRNA expression in human THP-1 monocytes. All compounds were inactive between 0.001microM and 10microM when tested alone. However, podophyllotoxin (0.1 microM) enhanced LPS-induced NF-kappa B activation and IL-1beta mRNA expression between 2 and 3-fold. In contrast, LPS-induced TNF-alpha mRNA expression was decreased between 3 and 6-fold. Comparable results were also observed with the three analogs acetylpodophyllotoxin, 4'-demethylpodophyllotoxin and alpha-peltatin. The remaining three analogs (podophyllotoxin-4-O-glucoside, beta-peltatin-beta-D-glucopyransoide and 1,2,3,4-dehydrodesoxypodophyllotoxin) were inactive. Clearly certain structural features such as the presence of a glycosidic group or ring aromatization results in loss of biological activity. Interestingly, the analogs that were inactive in our assays have also been previously shown to lack affinity for tubulin binding. These results suggest that during the initial hours of exposure to podophyllotoxin or specific analogs these compounds do not act as independent stimulants of human monocyte activation, but can selectively enhance or suppress LPS-induced cytokine gene expression.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Interleucina-1/metabolismo , Lignanas/farmacologia , Lipopolissacarídeos/farmacologia , Monócitos/efeitos dos fármacos , Fragmentos de Peptídeos/metabolismo , Podofilotoxina/análogos & derivados , Podofilotoxina/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Células Cultivadas , Eletroforese em Gel de Ágar , Humanos , Interleucina-1beta , Espectroscopia de Ressonância Magnética , Monócitos/metabolismo , NF-kappa B/metabolismo , RNA Mensageiro/metabolismo , Relação Estrutura-Atividade , Fatores de Tempo
10.
Mem Inst Oswaldo Cruz ; 89(4): 553-9, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-8524057

RESUMO

Experimental infections of the phytophagous Hemiptera Dysdercus peruvianus with different trypanosomatids were studied for up to 55 days by light microscopy while the course of infection with Leptomonas seymouri and the Leptomonas isolate 49/553G.O. was analyzed by electron microscopy. Rates of infection of D. peruvianus varied according to the infecting flagellate. The lower part of the midgut was found to be the preferential site of colonization where most flagellates were found isolated or arranged in clumps or rosettes. Specialized junctional structures with host cells were never observed. Flagellates could also be seen inside midgut cells within a parasitophorous vacuole. Infection of haemocoele and salivary glands was also observed.


Assuntos
Hemípteros/parasitologia , Infecções por Protozoários/parasitologia , Trypanosomatina/ultraestrutura , Animais , Interações Hospedeiro-Parasita
11.
Ecotoxicol Environ Saf ; 54(3): 339-45, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12651190

RESUMO

The Atlantic forest species near the industrial complex of Cubatão, Brazil have been subjected to heavy air pollution for decades. In this study, we used some physiological parameters (gas exchange, growth and chemical contents) to biomonitor the effects of air pollution on Tibouchina pulchra, one of the most common tree species in this forest. Under standardized conditions, saplings were exposed to the environment from April to July and from July to September of 1998, at three different sites in the vicinity of the industrial complex: the Valley of Pilões River (VP), the control area; the Valley of Mogi River (VM), near fertilizer, metallurgical, and cement industries sustaining high concentrations of fluorides, N and S oxides, and particulate materials; and Caminho do Mar (CM), near petrochemical industries under N and S oxides, photooxidants, and organic compounds. Plants exposed to CM and VM conditions presented visible injuries, reductions in net photosynthesis, growth parameters, and ascorbate concentrations, and increased F, N, and S foliar concentrations. These results indicate that the environmental conditions around these industries are still harmful to plants.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Melastomataceae/crescimento & desenvolvimento , Melastomataceae/fisiologia , Fotossíntese , Brasil , Monitoramento Ambiental , Indústrias , Folhas de Planta/química
12.
Nat Toxins ; 7(1): 39-43, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10441036

RESUMO

Bioassay-guided fractionation of the hexane:ethyl acetate (1:1) extract of the leaves of Leucophyllum frutescens (Berl.) I.M.Johnst (Scrophulariaceae) led to the isolation of its phytotoxic constituents diayangambin (1), epiyangambin (2), diasesartemin (3) and epiashantin (4). Phytotoxicity was demonstrated as inhibition of seed germination of Agrostis stolonifera cv. penncross (Poaceae) and inhibition of development of Lactuca sativa L. (Asteraceae) seedlings in a microassay using 24-well plates. Compound 1 was the most phytotoxic to L. sativa, showing strong inhibitory activity at 110 microM. Compound 1 was more active than 2 and 3 in inhibiting the growth of A. stolonifera with I(50) values of 160, 670 and 930 microM, respectively. At a concentration of 500 microM, these compounds inhibited all phases of onion root cell division. This is the first demonstration of antimitotic activity of these furofuran lignans, and the first report of their isolation from this species.


Assuntos
Herbicidas/isolamento & purificação , Herbicidas/toxicidade , Lignanas/isolamento & purificação , Lignanas/toxicidade , Magnoliopsida/química , Magnoliopsida/efeitos dos fármacos , Plantas Tóxicas/química , Germinação/efeitos dos fármacos , Herbicidas/química , Lignanas/química , Índice Mitótico/efeitos dos fármacos , Modelos Moleculares , Conformação Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/toxicidade , Folhas de Planta/química , Sementes/efeitos dos fármacos
13.
Planta Med ; 67(1): 97-9, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11270736

RESUMO

Rehydration of powdered tissues of Podophyllum peltatum L. prior to extraction with an organic solvent allows endogenous beta-glucosidases to hydrolyze lignan 4-O-beta-D-glucosides in situ and increase the yield of podophyllotoxin. Aqueous extraction of rhizomes and leaves of P. peltatum yielded 4- to 10-fold greater quantities of podophyllotoxin than the traditional ethanolic extraction. Most significantly, leaves were shown to contain over 52 mg of podophyllotoxin per g of dry weight (5.2%), exceeding levels previously reported from any source. These results point to the use of leaves harvested from cultivated P. peltatum as an attractive alternative to the destructive collection of natural populations.


Assuntos
Glucosídeos/química , Magnoliopsida/química , Podofilotoxina/química , Podofilotoxina/isolamento & purificação , Folhas de Planta/química , Podofilotoxina/análogos & derivados
14.
J Diarrhoeal Dis Res ; 11(3): 148-52, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8263302

RESUMO

Viral, bacterial and parasitic pathogens associated with diarrhoea were studied in infants and young children admitted to the paediatric clinic of the University Hospital of São Paulo during the period of 13 months. A recognised pathogenic organism was detected in 78% of the diarrhoeic patients, 6% of whom had a mixed infection with two agents. Enteropathogenic E. coli (EPEC) was the most common enteropathogen detected (22%), followed by rotavirus (19%) and adenovirus (10%). Altogether 6% had diarrhoea associated with Salmonella or Shigella and 3% showed diarrhoeal illness associated with astrovirus. Infants less than 6 months of age were most commonly infected with enterobacteria (35%), mainly enteropathogenic E. coli (30%), whereas children 6 months to 2 years presented more often with viruses (38%), mainly rotaviruses (25%). Enteropathogens were found during all seasons of the year and rotaviruses showed a seasonal variation.


Assuntos
Adenoviridae , Diarreia/microbiologia , Escherichia coli , Rotavirus , Doença Aguda , Fatores Etários , Brasil/epidemiologia , Diarreia/epidemiologia , Diarreia/parasitologia , Humanos , Lactente , Recém-Nascido , Estudos Longitudinais , Estações do Ano
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