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1.
Sci Total Environ ; 915: 170170, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38232843

RESUMO

The aim of this study was to assess the abundance of microplastics in the gastro-intestinal tracts of three commercially important fish species in the UK, to determine whether catch location, feeding habits and fish size influence the amount of microplastics within fish. Fish were collected from two rivers in the UK: the River Thames and the River Stour (East Anglia). Fish were collected from two sites in the River Thames and one site in the River Stour. Species selected were European flounder (Platichthys flesus), whiting (Merlangius merlangus), and Atlantic herring (Clupea harengus), and were chosen to represent benthic and pelagic feeding habits. Across all locations, 41.5 % of fish had ingested at least one microplastic particle (37.5 % of European flounder, 52.2 % of whiting, and 28.6 % of Atlantic herring). The average number by species was 1.98 (±3.50) microplastics/fish in European flounder, 2.46 (±3.10) microplastics/fish in whiting and 1.47 (±3.17) microplastics/fish in herring. There were no significant differences in the number or mass of microplastics in fish based on river, site, species or habitat. However, the number and mass of microplastics within benthic fish (European flounder) in the River Stour were significantly higher than in benthic fish from the River Thames. By number of microplastics, larger and heavier fish were more highly contaminated. This study enhances our understanding of microplastics in commercially important fish but highlights that fish contamination is not easily predicted by feeding habits or catch location alone. Exposure and uptake is likely to vary with changing environmental conditions. Fish size tends to be a good predictor of contamination, with larger fish generally containing more microplastics. This is the first study to directly compare concentrations of microplastics in fish from different UK rivers and the first evidence of microplastics in the River Stour.


Assuntos
Linguado , Poluentes Químicos da Água , Animais , Microplásticos , Rios , Plásticos , Estuários , Monitoramento Ambiental , Peixes , Reino Unido , Poluentes Químicos da Água/análise
2.
Nat Commun ; 13(1): 5005, 2022 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-36008385

RESUMO

Tropical forests take up more carbon (C) from the atmosphere per annum by photosynthesis than any other type of vegetation. Phosphorus (P) limitations to C uptake are paramount for tropical and subtropical forests around the globe. Yet the generality of photosynthesis-P relationships underlying these limitations are in question, and hence are not represented well in terrestrial biosphere models. Here we demonstrate the dependence of photosynthesis and underlying processes on both leaf N and P concentrations. The regulation of photosynthetic capacity by P was similar across four continents. Implementing P constraints in the ORCHIDEE-CNP model, gross photosynthesis was reduced by 36% across the tropics and subtropics relative to traditional N constraints and unlimiting leaf P. Our results provide a quantitative relationship for the P dependence for photosynthesis for the front-end of global terrestrial C models that is consistent with canopy leaf measurements.


Assuntos
Florestas , Fósforo , Carbono , Fotossíntese , Folhas de Planta/fisiologia , Árvores/fisiologia
3.
Ayu ; 34(1): 86-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24049411

RESUMO

According to Ayurveda, Kati Shoola is a disease with pain in lumbar region. Lumbar spondylolisthesis, anterior displacement of a vertebra or the vertebral column in relation to the vertebrae below, is one of the common causes. Current case study was carried out at Ayurveda Teaching hospital, Borella, to evaluate the efficacy of a treatment regimen used by Sri Lankan traditional physician family "Weerasinghe." A 59-year-old female with a 9-month history of lumbar spondylolisthesis was treated with this regimen. The patient had progressive pain in left lower back, right and left buttocks, and difficulty in bending forward over 5°. X-ray of lumbo sacral region indicated that patient was suffering from Grade 3 lumbar spondylolisthesis. She was treated for 65 days with four treatment packages consisting of 13 prepared medicines. The response to the treatment was recorded and therapeutic effects were evaluated through symptomatic relief. Clinical symptoms were significantly reduced and degree of anterior flexion increased from 5° to 90°. However, X-rays indicated that the patient was still suffering from Grade 3 lumbar spondylolisthesis. This regimen is effective in successfully treating Kati Shoola (lumbar spondylolisthesis) by helping to reduce the symptoms and improving the degree of anterior flexion.

4.
Plant Cell Environ ; 36(7): 1268-84, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23278101

RESUMO

We tested whether snow gum (Eucalyptus pauciflora) trees growing in thermally contrasting environments exhibit generalizable temperature (T) response functions of leaf respiration (R) and fluorescence (Fo). Measurements were made on pot-grown saplings and field-grown trees (growing between 1380 and 2110 m a.s.l.). Using a continuous, high-resolution protocol, we quantified T response curves of R and Fo--these data were used to identify an algorithm for modelling R-T curves at subcritical T's and establish variations in heat tolerance. For the latter, we quantified Tmax [T where R is maximal] and Tcrit [T where Fo rises rapidly]. Tmax ranged from 51 to 57 °C, varying with season (e.g. winter summer). Tcrit ranged from 41 to 49 °C in summer and from 58 to 63 °C in winter. Thus, surprisingly, leaf energy metabolism was more heat-tolerant in trees experiencing ice-encasement in winter than warmer conditions in summer. A polynomial model fitted to log-transformed R data provided the best description of the T-sensitivity of R (between 10 and 45 °C); using these model fits, we found that the negative slope of the Q10 -T relationship was greater in winter than in summer. Collectively, our results (1) highlight high-T limits of energy metabolism in E. pauciflora and (2) provide a framework for improving representation of T-responses of leaf R in predictive models.


Assuntos
Respiração Celular , Eucalyptus/fisiologia , Temperatura , Algoritmos , Eucalyptus/citologia , Umidade , Modelos Biológicos , Folhas de Planta/citologia , Folhas de Planta/fisiologia
6.
Ayu ; 31(1): 58-61, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22131686

RESUMO

Kaphaja Shira Shula is one of the Shiro Roga. Chronic sinusitis is inflammation of the sinuses behind the forehead, cheeks, and eyes, which continues for a long time or keeps recurring. Kaphaja Shira Shula can be correlated with Chronic Sinusitis. The decoction of Katuwelbatu Deduru Katuka is mentioned in Watika Prakaranaya, a book on Sri Lankan Traditional Medicine. The ingredients of this decoction are Solanum xanthocarpum, Cuminum cyminum, Nigella sativa, Picroihiza kurrota and Clerodendrum serratum. But in this study Saussurea lappa is used instead of C. serratum with the experience of traditional physician, Weerasinghe. Aim of this study was to scientifically evaluate the efficacy of this decoction in Kaphaja Shira Shula. Eighty patients suffering from Chronic sinusitis were selected from Ayurveda Teaching Hospital, Borella, Sri Lanka and randomly divided into two groups. X-ray of Para nasal sinuses and total white cell count before treatment and after treatment were recorded. Group one was treated with 120 ml of decoction of Katuwelbatu Deduru Katuka and Group two with 120 ml of placebo twice a day for twenty one days. Partial and complete symptomatic relief and reduction in esinophil count in the blood were observed in the treated group. It is observed that decoction of Katuwelbatu Deduru Katukadiya can be used in treatment of Kaphaja Shira Shula (Chronic sinusitis) effectively.

7.
Ceylon Med J ; 47(3): 83-5, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12449772

RESUMO

OBJECTIVE: To determine effectiveness and safety of the combination of artesunate, sulphadoxine + pyrimethamine and primaquine in the treatment of P falciparum malaria. DESIGN: A hospital based prospective study. SETTING: Base Hospital, Moneragala. METHODS: In 30 P falciparum infected patients admitted to the hospital, blood was taken for estimation of haemoglobin, white cell counts, and serum levels of aspartate aminotransferase, alanine aminotransferase, bilirubin and creatinine. They were administered artesunate, sulphadoxine + pyrimethamine (S + P) and primaquine on day 0 (artesunate 4 mg/kg, sulphadoxine 25 mg/kg, pyrimethamine 1.25 mg/kg and primaquine 0.75 mg/kg), and only artesunate on days 1 and 2 (artesunate 4 mg/kg each day). Blood was examined for malarial parasites, and patients were assessed on days 1, 2, 7, 14, 21 and 28. Patients assessed the severity of selected symptoms. Biochemical analyses were done on day 0 and repeated on days 7 and 28. RESULTS: Eight patients presented with fever which resolved in 7 patients in 48 hours. Asexual parasites were cleared in 80% of the 30 patients within 24 hours of treatment and in all 30 by day 7. Gametocytaemia cleared in all patients by day 14. There were no adverse effects experienced by the patients. The white cell and differential counts, liver enzymes and creatinine levels were within normal limits on all follow up days. CONCLUSIONS: The combination of artesunate, S + P and primaquine was found to be effective and safe in the treatment of uncomplicated P falciparum malaria.


Assuntos
Artemisininas/uso terapêutico , Malária Falciparum/tratamento farmacológico , Pirimetamina/uso terapêutico , Sesquiterpenos/uso terapêutico , Sulfadoxina/uso terapêutico , Artesunato , Combinação de Medicamentos , Quimioterapia Combinada , Humanos , Malária Falciparum/sangue , Estudos Prospectivos , Resultado do Tratamento
8.
Inflammation ; 16(5): 497-507, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1428124

RESUMO

Contact of plasma with a negatively charged surface activates prekallikrein and factor XII reciprocally. Activation of prekallikrein by several activators was impaired in bovine plasma when compared to that in human plasma. The activated partial thromboplastin time of bovine plasma, induced by several activators, was significantly longer than that of human plasma. Cleavage of [125I]factor XII was optimum at 10 min in human plasma but took up to 60 min in bovine plasma. Addition of bovine plasma to human plasma caused significant inhibition of dextran sulfate-induced prekallikrein activation, indicating that the impaired rate of contact activation in bovine plasma is due to the presence of inhibitors. The inhibitory effect was greater at lower concentrations of dextran sulfate but could not be abolished by increasing the concentration. The inhibitory activity eluted in two peaks at low and medium salt concentrations on carboxymethyl ion-exchange chromatography of bovine plasma.


Assuntos
Sulfato de Dextrana/antagonistas & inibidores , Plasma/fisiologia , Pré-Calicreína/metabolismo , Animais , Testes de Coagulação Sanguínea , Bovinos , Cromatografia por Troca Iônica , Ativação Enzimática/efeitos dos fármacos , Fator XII/metabolismo , Humanos , Radioisótopos do Iodo
9.
Endocrinology ; 131(4): 1777-81, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1396322

RESUMO

Glandular (tissue) kallikreins are known to be involved in the posttranslational modification of protein hormones and growth factors in addition to their classical role as the bradykinin-releasing enzyme in tissues. They have been shown to be present in many tissues, such as the pancreas, salivary glands, pituitary, and testes. The objective of this study was to investigate the presence of kallikrein in the rabbit placenta. Day 21 pregnant rabbit fetal placentae were teased apart in medium 199, washed thoroughly, and incubated in fresh medium for 6 h at 37 C. The resulting placental conditioned medium (FPI) was found to have 31.35 +/- 4.3 U glandular kallikrein-like amidolytic activity/mg protein toward the chromogenic peptide substrate S-2266 (1 U is defined as the amount of p-nitroaniline liberated by 10 ng rat urinary kallikrein). Using an enzyme-linked immunosorbent assay with sheep serum raised against rat urinary kallikrein, the glandular kallikrein concentration of FPI was estimated to be 4.56 +/- 0.857 micrograms/mg protein. Upon Western blot analysis, FPI gave a positive band of 45,000 in the presence of beta-mercaptoethanol. In the absence of beta-mercaptoethanol, a band of 138,000 was observed, indicating that in FPI, kallikrein is present bound to a high mol wt binding protein. These results strongly indicate the presence of glandular kallikrein in rabbit fetal placentae.


Assuntos
Calicreínas/metabolismo , Placenta/metabolismo , Animais , Western Blotting , Compostos Cromogênicos , Meios de Cultura , Ensaio de Imunoadsorção Enzimática , Feto , Calicreínas/urina , Oligopeptídeos , Pâncreas/metabolismo , Coelhos , Ratos , Suínos , Calicreínas Teciduais
10.
Inflammation ; 16(3): 205-13, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1500097

RESUMO

Contact of human plasma with a negatively charged surface such as dextran sulfate activates prekallikrein to kallikrein, which releases the vasoactive peptide bradykinin from high-molecular-weight kininogen. The dextran sulfate-induced activation of prekallikrein at 0 degree C (assayed by its amidolytic activity on the chromogenic substate S-2302) could not be observed in either bovine or rabbit plasmas when compared to human plasma. Neither bovine nor rabbit plasma inhibited the amidolytic activity of contact-activated human plasma at 0 degrees C. The activation of prekallikrein in human plasma was significantly inhibited by the addition of bovine plasma but not by rabbit plasma. Bovine plasma (0.025 units, 1 unit = 1 ml of plasma) caused 68.8% inhibition of prekallikrein activation. Eighty percent of the inhibitory property of bovine plasma was present in the greater than 30,000-molecular-weight fraction. These results indicate the presence of an inhibitor(s) of prekallikrein activation in bovine plasma.


Assuntos
Bovinos/sangue , Pré-Calicreína/metabolismo , Coelhos/sangue , Animais , Compostos Cromogênicos/metabolismo , Sulfato de Dextrana/farmacologia , Ativação Enzimática/efeitos dos fármacos , Fator XII/antagonistas & inibidores , Humanos , Calicreínas/metabolismo , Oligopeptídeos/metabolismo , Especificidade da Espécie
11.
Thromb Res ; 33(6): 625-31, 1984 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-6719404

RESUMO

Cerebroside sulphate or sulphatides, present in erythrocyte and leucocyte cell membranes, have recently been shown to be a potent activator of the contact phase of coagulation. Platelet factor-four (PF4), purified from human washed platelets, was found to inhibit the sulphatide induced APTT and plasma prekallikrein activation in a dose dependent manner. A four-fold increase in the sulphatide-APTT was observed in 156pM PF4 in the reaction mixture and 30% inhibition of prekallikrein activation was observed at 1.6nM. PF4 was found to be an approximately 1000-fold more potent inhibitor than protamine sulphate in inhibiting activation of clotting but was not as potent in inhibiting activation of prekallikrein. The physiological form of PF4 as released from platelets, was also found to cause inhibition of plasma prekallikrein activation, with 50% inhibition observed when the concentration of PF4 in plasma was 2.25 g/ml (0.29 M). The ability of PF4 to inhibit the contact activation reactions induced by sulphatides may be of some physiological significance in that when released during platelet activation and vessel wall injury, it may have a protective effect against the development of thrombosis.


Assuntos
Coagulação Sanguínea/efeitos dos fármacos , Fator Plaquetário 4/fisiologia , Sulfoglicoesfingolipídeos/farmacologia , Humanos , Técnicas In Vitro , Tempo de Tromboplastina Parcial , Pré-Calicreína/fisiologia , Protaminas/farmacologia , Tempo de Protrombina , Tempo de Trombina
12.
Thromb Haemost ; 51(1): 37-41, 1984 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-6202021

RESUMO

Collagen mediated platelet aggregation caused -5.6 +/- 6.7% inhibition and +39.1 +/- 15.2% potentiation of prekallikrein activation in plasma from normal healthy volunteers between 20-40 and 50-65 years of age, respectively (n = 15, p less than 0.01). The amounts of platelets factor-four (PF4) released in the two groups were not significantly different. Collagen treatment in the presence of indomethacin caused +11.5 +/- 3.6% and +59.6 +/- 19.5% potentiation in the 20-40 and 50-65 age groups respectively (p less than 0.02). Adrenaline mediated platelet aggregation caused -55.2 +/- 7.1% and -35.2 +/- 8.3% inhibition in the 20-40 and 50-65 age groups, respectively. Collagen treatment of platelet-deficient-plasma and platelet-rich-plasma in EDTA also caused potentiation of prekallikrein activation. The results indicate that the observed degree of prekallikrein activation after platelet aggregation is a net result of the inhibitory effect of PF4 and the potentiatory effect of activated platelets. The potentiatory effect was greater after collagen treatment as compared to adrenaline treatment, and in the 50-65 age group as compared to the 20-40 age group.


Assuntos
Colágeno/farmacologia , Calicreínas/análise , Agregação Plaquetária/efeitos dos fármacos , Fator Plaquetário 4/metabolismo , Pré-Calicreína/análise , Adulto , Fatores Etários , Idoso , Plaquetas/metabolismo , Sulfato de Dextrana , Dextranos/farmacologia , Epinefrina/farmacologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
13.
Thromb Res ; 32(6): 519-29, 1983 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-6198747

RESUMO

Platelet products released by ADP mediated platelet aggregation or by repeated freeze-thawing of platelet-rich-plasma caused inhibition of the dextran sulphate induced activation of prekallikrein, measured amidolytically, in subsequently prepared platelet-poor-plasma. Platelet products did not inhibit the amidolytic activity of contact activated-plasma. Addition of antiserum to platelet factor-4 (PF4) neutralized the inhibitory effect of platelet products towards prekallikrein activation. When platelet released products were fractionated by heparin affinity chromatography, 93% of the PF4 applied and 86% of the inhibitory activity of the starting material was recovered in the high-affinity fraction.


Assuntos
Calicreínas/biossíntese , Fator Plaquetário 4/fisiologia , Pré-Calicreína/biossíntese , Difosfato de Adenosina/farmacologia , Adulto , Especificidade de Anticorpos , Cromatografia de Afinidade , Dextranos/farmacologia , Ativação Enzimática/efeitos dos fármacos , Humanos , Soros Imunes/imunologia , Plasma/análise , Agregação Plaquetária/efeitos dos fármacos , Fator Plaquetário 4/imunologia , Fator Plaquetário 4/isolamento & purificação
14.
Thromb Res ; 31(1): 87-97, 1983 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-6193602

RESUMO

Pentosan polysulphate (PPS, Hemoclar, MW 6,700) was observed to have a low affinity for ATIII-Sepharose eluting at 0.3M NaCl. Tested in vitro it had, as previously reported, a low potency as an anticoagulant, about 10 times less than heparin on a weight for weight basis. Only the KCCT was affected by low concentrations of PPS unlike heparin by which both thrombin time and KCCT were affected. Upon injection of PPS subcutaneously (50mg) the heparin activity measured by chromogenic anti factor Xa and by KCCT was in the ratio of 2:1. When injected intravenously (40mg) into 3 healthy volunteers a significant prolongation of a modified prothrombin time was observed in 2 subjects. When PPS was added to heparin containing plasma it was observed to completely inhibit heparin at low concentrations (2:1 on a weight to weight basis) when measured in the thrombin and prothrombin time but not in the KCCT. The antiheparin effect of PPS was also observed in a purified system in obviating the heparin potentiation of the rate of inhibition of thrombin by antithrombin III. Observations showed that at higher concentrations of PPS it acted by directly inhibiting thrombin without the intervention of antithrombin III but also to potentiate the rate of fibrin monomer polymerization.


Assuntos
Anticoagulantes , Antagonistas de Heparina , Poliéster Sulfúrico de Pentosana/farmacologia , Polissacarídeos/farmacologia , Antitrombina III/metabolismo , Humanos , Técnicas In Vitro , Injeções Intravenosas , Injeções Subcutâneas , Masculino , Poliéster Sulfúrico de Pentosana/administração & dosagem , Trombina/metabolismo , Tempo de Coagulação do Sangue Total
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