RESUMO
Background: Atrial fibrillation (AF) is the most common cardiac arrhythmia. Catheter ablation aims to restore sinus rhythm. However, relapses occur in up to 30% of patients. A Mediterranean diet (MedDiet) enriched with extra-virgin olive oil (EVOO) substantially reduced the incidence of AF in the PREDIMED trial. The PREDIMAR will test a similar intervention in secondary prevention. Methods: PREDIMAR is a multicenter, randomized, single-blind trial testing the effect of a MedDiet enriched with EVOO to reduce tachyarrhythmia relapses after AF ablation. The primary outcome is the recurrence of any sustained atrial tachyarrhythmia after ablation (excluding those occurring only during the first 3 months after ablation). The target final sample size is 720 patients (360 per group) recruited from 4 Spanish hospitals. A remote intervention, maintained for 2 years, is delivered to the active intervention group including periodic phone calls by a dietitian and free provision of EVOO. The control group will receive delayed intervention after trial completion. Routine electrocardiogram (ECG) and Holter ECG are performed, and a portable cardiac rhythm monitoring device is provided to be worn by participants during 15 months. Results: Recruitment started in March 2017. Up to July 2019, 609 patients were randomized (average inclusion rate: 5.3 patients/wk). Retention rates after 18 months are >94%. Conclusions: If our hypothesis is confirmed, the utility of the MedDiet enriched with EVOO in slowing the progression of AF will be proven, preventing recurrences and potentially reducing complications.
Assuntos
Fibrilação Atrial/prevenção & controle , Fibrilação Atrial/cirurgia , Dieta Mediterrânea , Azeite de Oliva/uso terapêutico , Prevenção Secundária/métodos , Ablação por Cateter , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/prevenção & controle , Recidiva , Método Simples-Cego , Taquicardia/prevenção & controle , Fatores de TempoRESUMO
BACKGROUND: Storing pleural fluid samples for research purposes is a common practice, but whether adenosine deaminase (ADA), an enzyme used for the diagnosis of tuberculous pleuritis, is stable over long periods of time is unknown. METHODS: We evaluated the stability of pleural ADA concentrations in 223 samples frozen at -800C as compared to values obtained immediately following the initial thoracentesis. Sample storage time ranged from several months to slightly more than 10 years. RESULTS: ADA activity was stable for up to 2.6 years. Afterwards, it decreased 6 to 8 U/L, enough to drop 2 (3.3%) tuberculous patients below the diagnostic ADA cutoff. CONCLUSIONS: As far as ADA enzymatic activity is concerned, pleural fluid samples are viable for extended periods of time. However, some caution in interpreting results from specimens stored for > 2.6 years is prudent.
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Adenosina Desaminase/metabolismo , Pleura/enzimologia , Humanos , Manejo de Espécimes , Tuberculose Pleural/enzimologiaRESUMO
A Continuous Wave (CW) sub-THz photonic synthesis setup based on a single Passively Mode-Locked Laser Diode (PMLLD) acting as a monolithic Optical Frequency Comb Generator (OFCG) and highly selective optical filtering has been implemented to evaluate the phase noise performance of the generated sub-THz signals. The analysis of the synthesized sub-THz signals up to 120 GHz gives as a result an effective reduction of the electrical linewidth when compared to direct harmonic generation that begins at 50 GHz and becomes greater as the frequency increases. The phase noise reduction offered by the setup, along with its integration potential, cost and bandwidth, make it a promising candidate to the development of an integrated and high performance low phase noise local oscillator in the sub-THz range.
Assuntos
Lasers Semicondutores , Óptica e Fotônica/instrumentação , Óptica e Fotônica/métodos , Processamento de Sinais Assistido por Computador/instrumentação , Artefatos , Desenho de EquipamentoRESUMO
Given their large surface area and versatile chemical reactivity, single-walled carbon nanotubes (SWCNTs) are regarded as the basis of new pharmacological complexes. In this study, SWCNTs are chemically functionalized with fluorescein, folic acid, and capecitabine, a drug that is commonly used against colorectal cancer. These functionalized SWCNTs are dispersed in water by taking advantage of their synergistic interaction with type-II nanocrystalline cellulose (II-NCC), and the resulting colloidal system is tested in vitro on both normal (differentiated) and cancerous (proliferative) human colon cells (Caco-2). The functionalized SWCNT/II-NCC hybrids show a higher activity than the reference (capecitabine) against the Caco-2 cancer cell line. However, this effect appears to be intrinsically associated with the SWCNT/II-NCC complex, particularly boosted by fluorescein, as the presence of capecitabine is not required. In addition, confocal microscopy fluorescence imaging using cell cultures highlights the enormous potential of this nanohybrid platform for colon cancer theranostics.
Assuntos
Neoplasias do Colo , Nanotubos de Carbono , Células CACO-2 , Celulose , Neoplasias do Colo/tratamento farmacológico , Humanos , Nanotubos de Carbono/químicaRESUMO
The present work determined the minimum alveolar concentrations (MAC) of halothane, isoflurane and sevoflurane in adult female gerbils (n=24). Animals were placed in a chamber for anaesthetic induction before performing tracheal intubation. The tracheal tube was connected to a non-rebreathing circuit with minimal dead space. Body temperature, blood pressure, heart and respiratory rates and end-tidal volatile anaesthetic levels were measured continuously. MAC was determined using a standard noxious stimulus (tail-clamp). All experiments were performed at the same time of the day, body temperature was maintained constant and blood-gas analysis was performed to confirm that values were within normal limits. The mean+/-SD MAC values were 1.06+/-0.11% halothane (n=8), 1.55+/-0.08% isoflurane (n=8) and 2.90+/-0.12% sevoflurane (n=7). Cardiovascular parameters at 1xMAC did not differ significantly among anaesthetics but the respiratory rate was significantly higher in the halothane group than in the isoflurane and sevoflurane groups. The SpO2 values recorded throughout anaesthesia and the pH and partial oxygen pressure values determined at the end of the study did not differ among the studied anaesthetics at 1xMAC. These data suggest that the MAC for halogenated inhalant anaesthetics in gerbils is lower than the average MAC values obtained in rats and mice.
Assuntos
Anestésicos Inalatórios/farmacocinética , Halotano/farmacocinética , Isoflurano/farmacocinética , Éteres Metílicos/farmacocinética , Alvéolos Pulmonares/metabolismo , Animais , Gasometria , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Temperatura Corporal/efeitos dos fármacos , Temperatura Corporal/fisiologia , Feminino , Gerbillinae , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Intubação Intratraqueal , Respiração/efeitos dos fármacos , SevofluranoRESUMO
OBJECTIVE: We analysed the genetic polymorphisms in platelet glycoproteins (GP) Ib-alpha, Ia/IIa and IIb/IIIa and their correlation with the development of arterial thrombosis and preclinical arteriosclerosis in patients with antiphospholipid syndrome (APS) or with systemic lupus erythematosus (SLE). METHODS: We included 131 patients with APS (86 with primary APS and 45 with APS associated with SLE), 102 patients with SLE and 160 healthy controls. GP Ib-alpha VNTR polymorphism, GP Ia/IIa 807 C/T polymorphism and GP IIb/IIIa PlA1/2 polymorphism were determined by polymerase chain reaction. Thrombotic events were assessed clinically and confirmed by objective methods. The presence of preclinical arteriosclerosis was evaluated by a carotid ultrasound study in a subgroup of 70 patients with SLE measuring the intima-media wall thickness and the presence of arteriosclerotic plaque. RESULTS: A total of 50 episodes of arterial thrombosis in 36 patients with APS have been registered. We found a significant correlation between the 807 T/T genotype of GP Ia/IIa and arterial thrombosis (22% vs 7%, p = 0.04; OR 3.59, 95% CI 1.20 to 10.79). The VNTR Ib-alpha and P1A1/2 IIb/IIIa polymorphisms were not associated with arterial thrombosis in patients with APS when individually analysed. The coexistence of both 807 T and PlA2 alleles increased the arterial thrombosis risk (28% vs 7%, p = 0.005; OR 4.84, 95% CI 1.67 to 13.96). In patients with SLE, no relationship was found between the presence of carotid arteriosclerotic plaque and separate polymorphisms of platelet GP. The coexistence of alleles 807 T of GP Ia/IIa and PlA2 of GP IIb/IIIa was associated with the presence of carotid plaque (35% vs 4%, p = 0.002; OR 12.92, 95% CI 2.39 to 69.81). CONCLUSIONS: The T/T genotype of 807 C/T polymorphism of GP Ia/IIa may be an additional risk for the development of arterial thrombosis in APS. The coexistence of both 807 T and PlA2 alleles increased the arterial thrombosis risk in patients with APS and preclinical arteriosclerosis in patients with SLE.
Assuntos
Síndrome Antifosfolipídica/genética , Lúpus Eritematoso Sistêmico/genética , Glicoproteínas da Membrana de Plaquetas/genética , Polimorfismo Genético , Adulto , Análise de Variância , Síndrome Antifosfolipídica/sangue , Síndrome Antifosfolipídica/complicações , Arteriosclerose/sangue , Arteriosclerose/complicações , Arteriosclerose/genética , Artérias Carótidas/diagnóstico por imagem , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Feminino , Predisposição Genética para Doença , Heterozigoto , Humanos , Integrina alfa2/genética , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/complicações , Masculino , Pessoa de Meia-Idade , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/genética , Fatores de Risco , Trombose/sangue , Trombose/complicações , Trombose/genética , UltrassonografiaRESUMO
OBJECTIVES: The plotting of pressure-volume curves and the performance of alveolar recruitment maneuvers are common practices in the care of patients with adult respiratory distress syndrome (ARDS), even though potentially harmful hemodynamic effects are associated with sustaining a high intrathoracic pressure. Our aim was to analyze hemodynamic and ventilatory changes related to these 2 maneuvers and to assess the short-term effectiveness of recruitment. PATIENTS AND METHODS: The patients had ARDS and were being monitored with a catheter connected to a PiCCO system. All measurements were taken in sinus rhythm and with adequate vascular filling. Values recorded during plotting of the quasistatic pressure-volume curve and the recruitment maneuver (sustained airway pressure of 40 cm H2O) were the cardiac index, mean arterial pressure, heart rate, systolic volume index, and oxygen saturation (SpO2). Blood gas measurements were recorded before the maneuvers and 15 minutes afterwards. RESULTS: All parameters decreased significantly in the 14 patients studied. The mean (SD) maximum decreases, from which all patients recovered within 2 minutes, were as follows: cardiac index, 26% (16%); mean arterial pressure, 6% (6%); heart rate, 4% (5%), systolic volume index, 21% (15%); and SpO2, 3% (3%). Significant increases in PaO2 (7% [6%]) and the ratio of PaO2 to the fraction of inspired oxygen were recorded after the recruitment maneuver (P=.016 and P=.014, respectively), but the changes were not clinically significant. CONCLUSIONS: The hemodynamic disturbances associated with the alveolar recruitment maneuver based on sustaining a high end-expiratory pressure and the minor improvement in oxygenation achieved as a result suggest that the routine use of that maneuver in ARDS patients is of questionable value.
Assuntos
Hemodinâmica , Síndrome do Desconforto Respiratório/fisiopatologia , Síndrome do Desconforto Respiratório/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modalidades de FisioterapiaRESUMO
OBJECTIVE: To analyze the frequency and methods of sedation used in the context of regional anesthesia in adults by means of a national survey. MATERIAL AND METHODS: We carried out a survey of participants at the courses of an anesthesiology training organization (Fundación Europea de Enseñanza en Anestesiología), held in Spain in 2006. The survey questionnaires asked about indications for sedation used during surgery under regional anesthesia as well as the form of administration, follow-up, and complications. RESULTS: A total of 375 questionnaires were sent out and 185 responses were received (49.3%). Sedation is always used to accompany regional anesthesia by 69.2% of the respondents; 13.5% of them discuss the technique to be used with the patient and come to an agreement. The same type of sedation, regardless of the regional block performed, is used by 49.2% of respondents, and 64.3% use a scale to evaluate the level of sedation. The most favored sedation technique is continuous infusion, followed by target controlled infusion and boluses on demand. The most commonly used technique is sedation with bolus injections. Sixty percent use a single agent and 38.9% use combinations. The most commonly reported adverse effects are variability of patient response (53.5%) and respiratory complications (27%). In cases of ineffective regional blockade, 49.2% of those surveyed switch to general anesthesia. CONCLUSIONS: Sedation is very often used to complement regional anesthesia in adult patients. Even though continuous infusion is considered to be the most appropriate form of administration, the most commonly used form is injection of boluses. Sedation with a single drug is used more frequently than drug combinations. Variability of individual response is the complication most commonly reported by the respondents.
Assuntos
Anestesia por Condução , Sedação Consciente/estatística & dados numéricos , Adjuvantes Anestésicos/administração & dosagem , Adulto , Sedação Consciente/efeitos adversos , Sedação Consciente/métodos , Coleta de Dados , Feminino , Humanos , Hipnóticos e Sedativos/administração & dosagem , Hipnóticos e Sedativos/efeitos adversos , Infusões Intravenosas , Injeções Intravenosas , Complicações Intraoperatórias/epidemiologia , Complicações Intraoperatórias/etiologia , Masculino , Midazolam/administração & dosagem , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Padrões de Prática Médica/estatística & dados numéricos , Espanha , Inquéritos e QuestionáriosRESUMO
A non-conventional modification of exfoliated few-layer graphene (FLG) with different arynes under microwave (MW) irradiation and solvent-free conditions is reported. The described approach allows reaching fast, efficient and mild covalent functionalization of FLG.
RESUMO
BACKGROUND AND OBJECTIVE: Risk of morbidity and mortality increases for critically ill patients during transfers within the hospital. Such patients often require sedation, and suboptimal sedation is associated with hypertension, tachycardia, and ventilator dyssynchrony. The aim of this study was to assess level of sedation as indicated by monitoring of the bispectral (BIS) index during intrahospital transport of critical patients. PATIENTS AND METHODS: Thirty patients who required transport to the critical care unit within the hospital were studied prospectively. We recorded time in transport, the agent used for sedation and the dosage, the BIS index, mean arterial pressure (MAP), and heart rate before starting transport and upon arrival at the critical care unit. The data were recorded by an observer who was not assigned to patient care. RESULTS: The mean (SD) transport time was 13.9 (4.2) minutes. Midazolam was used in 26 patients and propofol in 4. Ten patients were given a bolus dose of cisatracurium before transfer started. Significant increases were observed in the BIS index (from 47 to 78, (P < .001), MAP (from 73 to 91 mmHg, P < .001), and heart rate (from 72 to 97 beats/min, P < .001) between the moment of starting transport and arrival at the critical care unit. Changes in the BIS index correlated significantly with changes in heart rate (r = 0.418, P = .024) but not with changes in MAP (r = 0.249, P = .19). CONCLUSIONS: Monitoring the BIS index during intrahospital transport of sedated, mechanically ventilated patients may be useful for detecting inadequate sedation.
Assuntos
Eletroencefalografia/métodos , Eletromiografia/métodos , Hipnóticos e Sedativos/uso terapêutico , Monitorização Fisiológica/métodos , Transferência de Pacientes , Atracúrio/administração & dosagem , Atracúrio/análogos & derivados , Atracúrio/farmacologia , Atracúrio/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Sedação Consciente , Cuidados Críticos/métodos , Cuidados Críticos/estatística & dados numéricos , Frequência Cardíaca/efeitos dos fármacos , Humanos , Hipnóticos e Sedativos/administração & dosagem , Hipnóticos e Sedativos/farmacologia , Unidades de Terapia Intensiva , Midazolam/administração & dosagem , Midazolam/farmacologia , Midazolam/uso terapêutico , Monitorização Fisiológica/estatística & dados numéricos , Bloqueadores Neuromusculares/administração & dosagem , Bloqueadores Neuromusculares/farmacologia , Bloqueadores Neuromusculares/uso terapêutico , Estudos Prospectivos , Respiração Artificial , Fatores de TempoRESUMO
Prostate-specific membrane antigen (PSMA), a glycoprotein expressed in the prostatic epithelium endowed with enzymatic activity, is a very promising diagnostic marker for the early detection of prostate cancer. In this study, we report a novel electrochemiluminescence ELISA-like immunosensor based on carbon nanotubes and a highly specific sandwich immunoassay for the PSMA detection. To fabricate the device, an optically transparent electrode was modified with doubly functionalized multi-walled carbon nanotubes carrying amine groups and a monoclonal anti-PSMA antibody. Subsequently, to complete the sandwich immunosensing device, a second specific monoclonal anti-PSMA antibody was labelled with a electrochemiluminescent probe. Under optimized experimental conditions, the proposed sensing device exhibits a performance exceeding that of the state of-the-art in terms of the limit of detection (LOD) and limit of quantification (LOQ) as good as 0.88 ng mL-1 and 2.60 ng mL-1, respectively, in real complex samples such as cell lysates. In addition, the unique role of carbon nanotubes is also discussed by comparison with an analogue sensor assembled without the nanocarbon-based material.
RESUMO
As a continuation of our studies on molecular epizootiology of piroplasmosis in Spain and other countries, we present in this contribution the finding of new hosts for some piroplasms, as well as information on their 18S rRNA gene sequences. Genetic data were complemented with sequences of apocytochrome b gene (whenever possible). The following conclusions were drawn from these molecular studies: Theileria annulata is capable of infecting dogs, since it was diagnosed in a symptomatic animal. According to cytochrome b sequences, isolates from cows and dog present slight differences. The same isolates showed, however, identical sequence in the 18S rRNA gene. This exemplifies well the usefulness of the mitochondrial gene for examining infra-specific variation. Babesia bovis is an occasional parasite of equines, since it was detected in two symptomatic horses. We found evidence of genetic polymorphism occurring in the 18S rRNA gene of Spanish T. equi-like and B. ovis isolates. B. bennetti from Spanish seagull is loosely related to B. ovis, and might represent a genetically distinct branch of babesids. A partial sequence of a cytochrome b pseudogene was obtained for the first time in Babesia canis rossi from South Africa. The pseudogene is distantly related to B. bigemina cytochrome b gene. These new findings confirm the ability of some piroplasms to infect multiple hosts, as well as the existence of a relatively wide genetic polymorphisms with respect to the cytochrome b gene. On the other hand, the existence of mtDNA-like pseudogenes of possible nuclear location in piroplasms is interesting due to their possible impact on molecular phylogeny studies.
Assuntos
Babesiose/veterinária , Citocromos b/genética , Piroplasmida/genética , RNA Ribossômico 18S/genética , Theileriose/epidemiologia , Animais , Babesiose/sangue , Babesiose/epidemiologia , Bovinos , Primers do DNA/química , Cães , Cabras , Cavalos , Dados de Sequência Molecular , Filogenia , Piroplasmida/classificação , Piroplasmida/isolamento & purificação , Reação em Cadeia da Polimerase/veterinária , Análise de Sequência de DNA/veterinária , Espanha/epidemiologia , Theileriose/sangueRESUMO
RNASET2 is a ubiquitously expressed acidic ribonuclease that has been implicated in diverse pathophysiological processes including tumorigeneis, vitiligo, asthenozoospermia, and neurodegeneration. Prior studies indicate that RNASET2 is induced in response to oxidative stress and that overexpression of RNASET2 sensitizes cells to reactive oxygen species (ROS)-induced cell death through a mechanism that is independent of catalytic activity. Herein, we report a loss-of-function genetic screen that identified RNASET2 as an essential gene for lipotoxic cell death. Haploinsufficiency of RNASET2 confers increased antioxidant capacity and generalized resistance to oxidative stress-mediated cell death in cultured cells. This function is critically dependent on catalytic activity. Furthermore, knockdown of RNASET2 in the Drosophila fat body confers increased survival in the setting of oxidative stress inducers. Together, these findings demonstrate that RNASET2 regulates antioxidant tone and is required for physiological ROS responses.
Assuntos
Apoptose , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Ribonucleases/fisiologia , Animais , Células CHO , Cricetinae , Cricetulus , Citoplasma/metabolismo , Expressão Gênica , Haploinsuficiência , Ácido Palmítico/farmacologia , RNA Nucleolar Pequeno/metabolismo , Proteínas Ribossômicas/genéticaRESUMO
BACKGROUND: Data are scarce on the natural history of chronic hepatitis C (CHC) in patients with mild hepatitis C who did not respond to anti-viral therapy. AIM: To predict the risk of progression to cirrhosis, identifying patients with the more urgent need for therapy with effective anti-virals. METHODS: A cohort of 1289 noncirrhotic CHC patients treated with interferon-based therapy between 1990 and 2004 in two referral hospitals were followed up for a median of 12 years. RESULTS: Overall, SVR was achieved in 46.6% of patients. Data from a randomly split sample (n = 832) was used to estimate a model to predict outcomes. Among nonresponders (n = 444), cirrhosis developed in 123 (28%) patients. In this group, the 3, 5 and 10-year cumulative probabilities of cirrhosis were 4%, 7% and 22%, respectively, compared to <1% in the SVR-group (P < 0.05). Baseline factors independently associated with progression to cirrhosis in nonresponders were: fibrosis ≥F2, age >40 years, AST >100 IU/L, GGT >40 IU/L. Three logistic regression models that combined these simple variables were highly accurate in predicting the individual risk of developing cirrhosis with areas under the receiving operating characteristic curves (AUC) at 5, 7 and 10 years of ~0.80. The reproducibility of the models in the validation cohort (n = 457, nonresponders = 244), was consistently high. CONCLUSIONS: Modelling based on simple laboratory and clinical data can accurately identify the individual risk of progression to cirrhosis in nonresponder patients with chronic hepatitis C, becoming a very helpful tool to prioritise the start of oral anti-viral therapy in clinical practice.
Assuntos
Hepatite C Crônica/complicações , Cirrose Hepática/etiologia , Cirrose Hepática/fisiopatologia , Adulto , Antivirais/uso terapêutico , Biomarcadores , Progressão da Doença , Feminino , Humanos , Interferons/uso terapêutico , Cirrose Hepática/tratamento farmacológico , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Reprodutibilidade dos TestesRESUMO
An 85-year-old man with a history of moderate chronic obstructive pulmonary disease in treatment with anticholinergic drugs was admitted to the recovery unit for postoperative monitoring after right inguinal herniorrhaphy surgery and removal of a strangulated intestinal section. On the third day after surgery the patient developed radiographic signs consistent with pneumonia and required mechanical ventilation. Two blood cultures and a respiratory secretion sample grew a microorganism identified as Hafnia alvei. H. alvei is a gram-negative bacillus that colonizes the digestive tract of humans and animals and in immunodepressed patients it can colonize the mouth and pharynx. Isolation of H. alvei is described in the literature on pediatric patients and those with a history of immune deficiency or chronic disease. Infection has a severe impact on general health. We report a rare and interesting case of pneumonia and bacteremia from H. alvei infection acquired by an immunocompetent patient soon after arrival in the postoperative recovery unit. The patient died of the infection.
Assuntos
Bacteriemia/microbiologia , Infecções por Enterobacteriaceae/microbiologia , Hafnia alvei/isolamento & purificação , Pneumonia Bacteriana/microbiologia , Complicações Pós-Operatórias/microbiologia , Idoso , Idoso de 80 Anos ou mais , Evolução Fatal , Hérnia Inguinal/cirurgia , Humanos , Imunocompetência , Masculino , Insuficiência de Múltiplos Órgãos/etiologia , Doença Pulmonar Obstrutiva Crônica/complicações , Sala de RecuperaçãoRESUMO
The intracellular localizations of ADPglucose pyrophosphatase (AGPPase) and ADPglucose pyrophosphorylase (AGPase) have been studied using protoplasts prepared from suspension-cultured cells of sycamore (Acer pseudoplatanus L.). Subcellular fractionation studies revealed that all the AGPPase present in the protoplasts is associated with amyloplasts, whereas more than 60% of AGPase is in the extraplastidial compartment. Immunoblots of amyloplast- and extraplastid-enriched extracts further confirmed that AGPase is located mainly outside the amyloplast. Experiments carried out to identify possible different isoforms of AGPPase in the amyloplast revealed the presence of soluble and starch granule-bound isoforms. We thus propose that ADPglucose levels linked to starch biosynthesis in sycamore cells are controlled by enzymatic reactions catalyzing the synthesis and breakdown of ADPglucose, which take place both inside and outside the amyloplast.
Assuntos
Isoenzimas/metabolismo , Nucleotidiltransferases/metabolismo , Diester Fosfórico Hidrolases/metabolismo , Árvores/enzimologia , Técnicas de Cultura de Células/métodos , Células Cultivadas , Glucose-1-Fosfato Adenililtransferase , Isoenzimas/isolamento & purificação , Nucleotidiltransferases/isolamento & purificação , Diester Fosfórico Hidrolases/isolamento & purificação , Plastídeos/enzimologiaRESUMO
Two isoforms of ADPglucose pyrophosphatase/phosphodiesterase (AGPPase) have been characterized using barley leaves (Hordeum vulgare L.). Whilst one of the isoforms, designated as soluble AGPPase1 (SAGPPase1), is soluble in low ionic strength buffers, the other, SAGPPase2, is extractable using cell wall hydrolytic enzymes or high salt concentration solutions, thus indicating that it is adventitiously bound to the cell wall. Both AGPPase isoforms are highly resistant to SDS, this characteristic being utilized to purify them to homogeneity after zymographic detection of AGPPase activity in SDS-containing gels. N-terminal and internal amino acid sequencing analyses revealed that both SAGPPase1 and SAGPPase2 are distinct oligomers of the previously designated HvGLP1, which is a member of the ubiquitously distributed group of proteins of unknown function designated as germin-like proteins (GLPs).
Assuntos
Glicoproteínas/química , Hordeum/enzimologia , Nucleotidiltransferases/química , Diester Fosfórico Hidrolases/química , Pirofosfatases/química , Sequência de Aminoácidos , Cromatografia em Gel , Eletroforese em Gel de Poliacrilamida , Glucose/metabolismo , Glucose-1-Fosfato Adenililtransferase , Temperatura Alta , Concentração de Íons de Hidrogênio , Cinética , Dados de Sequência Molecular , Nucleotídeos/metabolismo , Nucleotidiltransferases/isolamento & purificação , Oxirredutases/metabolismo , Proteínas de Plantas , Isoformas de Proteínas , Ribose/metabolismo , Análise de Sequência de Proteína , Dodecilsulfato de Sódio/metabolismo , Superóxido Dismutase/metabolismoRESUMO
The in vitro effects of levamisole and ivermectin against Echinococcus granulosus protoscoleces were studied by means of light and electron microscopy. Both drugs had a protoscolicidal activity that increased proportionally with increasing concentrations of the drugs. Ivermectin showed the more rapid effects and caused contraction and paralysis of protoscoleces. A paralyzing effect was also observed with levamisole, followed by irreversible tissue vacuolation leading to death.