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BACKGROUND: Neuroimaging studies suggest an association between apathy after deep brain stimulation (DBS) and stimulation of the ventral part of the subthalamic nucleus (STN) due to the associative fibers connected to the non-motor limbic circuits that are involved in emotion regulation and motivation. We have previously described three patients with severe apathy that could be fully treated after switching stimulation from a ventral electrode contact point to a more dorsal contact point. OBJECTIVES: To determine whether more dorsal stimulation of the STN decreases apathy compared to standard care in a multicenter randomized controlled trial with a crossover design. METHODS: We will include 26 patients with a Starkstein Apathy Scale (SAS) score of 14 or more after subthalamic nucleus (STN) deep brain stimulation (DBS) for refractory Parkinson's disease. This is a multicenter trial conducted in two teaching hospitals and one university medical center in the Netherlands after at least 3 months of STN DBS. Our intervention will consist of 1 month of unilateral dorsal STN stimulation compared to treatment as usual. The primary outcome is a change in SAS score following 1 month of DBS on the original contact compared to the SAS score following 1 month of DBS on the more dorsal contact. Secondary outcomes are symptom changes on the Movement Disorders Society-Unified Parkinson's Disease Rating Scale motor part III, Montgomery-Åsberg Depression Rating Scale, 39-item Parkinson's disease questionnaire, Parkinson's disease impulsive-compulsive disorders questionnaire, changes in levodopa-equivalent daily dosage, apathy rated by the caregiver, and burden and quality of life of the caregiver. TRIAL REGISTRATION: ClinicalTrials.gov NL8279. Registered on January 10, 2020.
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Apatía , Estimulación Encefálica Profunda , Enfermedad de Parkinson , Núcleo Subtalámico , Humanos , Enfermedad de Parkinson/terapia , Enfermedad de Parkinson/psicología , Estudios Cruzados , Estimulación Encefálica Profunda/efectos adversos , Estimulación Encefálica Profunda/métodos , Calidad de Vida , Resultado del Tratamiento , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Multicéntricos como AsuntoRESUMEN
BACKGROUND: Apathy is reported after subthalamic nucleus deep brain stimulation (STN DBS) and associated with a decreased quality of life in Parkinson's disease (PD) patients. Recent studies hypothesized that the location of active DBS contact point relative to the STN subdivisions (motor, associative and limbic) could be related to an increase of apathy. METHODS: 22 PD-patients that underwent STN DBS between January 2019 and February 2020 were divided in an apathy and non-apathy group using the change in the Starkstein Apathy Scale (SAS) after six months of DBS. For both groups the location of DBS electrodes was determined based on 7T MRI subthalamic network analysis, enabling visualization of the subdivisions and their projections relative to the active contact point. MDS-UPDRS III scores were included to evaluate DBS effect. RESULTS: In six patients a post-DBS increase in apathy score was assessed, versus 16 non-apathy patients. Network analysis showed that active contacts in apathy patients were more often positioned in or close to the area within the STN with high density of surrounding projections to associative cortex areas than in non-apathy patients; 63% apathy versus 42% (P = 0.02). The density of surrounding motor projections was lower in the group with increased apathy (18%) than in the group without increased apathy (38%, P = 0.01). Motor UPDRS improvement for the apathy group was 39% and for the non-apathy group 58% (n.s.) CONCLUSION: This new approach in patient-specific subthalamic 7T MRI network analysis visualized an anatomical connectivity substrate for apathy in DBS, with active electrode contacts predominantly in the associative STN.
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Apatía , Estimulación Encefálica Profunda , Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/diagnóstico por imagen , Enfermedad de Parkinson/terapia , Estimulación Encefálica Profunda/efectos adversos , Calidad de Vida , Resultado del Tratamiento , Imagen por Resonancia MagnéticaRESUMEN
BACKGROUND: Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is an established treatment for disabling motor symptoms of Parkinson's disease (PD) that persist despite optimal pharmacological treatment. Currently, DBS is not performed if there is concomitant significant cognitive impairment based on concerns of cognitive deterioration, higher complication rate and less functional improvement. However, this has not been investigated so far. METHODS: A single center, prospective, randomized, open-label, blinded end-point (PROBE design) pilot clinical trial is being performed. Patients are eligible for the trial if they have PD dementia (PDD), are able to provide informed consent, and experience disabling motor response fluctuations, bradykinesia, dyskinesia, or painful dystonia, despite optimal pharmacological treatment. In total 44 patients will be randomized to either STN-DBS accompanied by best medical treatment (DBS group) or to best medical treatment alone (BMT group). The primary outcome measure is the change from baseline to 30 weeks on the Movement Disorder Society-Unified Parkinson's Disease Rating Scale part III score in a standardized off-drug phase. The main secondary outcome measures consist of scales assessing cognitive aspects of daily living, neuropsychiatric symptoms and impulsive compulsive disorders. Additional secondary outcome measures include motor signs during on-drug phase, dyskinesia, motor fluctuations, cognitive performance, (severe) adverse events, treatment satisfaction, and caregiver burden. Patients will be followed during 52 weeks after randomization. DISCUSSION: The Deep Brain Stimulation for MOtor symptoms in patients with Parkinson's disease DEmentia (DBS-MODE) trial directly compares the effectiveness and safety of DBS with BMT in patients with PDD. TRIAL REGISTRATION: The DBS-MODE trial has been registered in the International Clinical Trial Registry Platform (NL9361) on the 24th of March 2021 ( https://trialsearch.who.int/Trial2.aspx?TrialID=NL9361 ).
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Enfermedad de Alzheimer , Estimulación Encefálica Profunda , Demencia , Discinesias , Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/terapia , Enfermedad de Parkinson/tratamiento farmacológico , Estimulación Encefálica Profunda/efectos adversos , Estimulación Encefálica Profunda/métodos , Estudios Prospectivos , Resultado del Tratamiento , Enfermedad de Alzheimer/terapia , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
A 31-year-old man visited the outpatient clinic Dermatology with an exacerbation of his atopic eczema. Since a few day vesicles and crusts had appeared and his eyelids were swollen. He was known to have eczema, for which he was treated with ciclosporin 200 mg 2 times a day (4 mg/kg per day) since four months. Under this treatment the eczema used to be under control. There were no neurological symptoms or vision problems. At physical examination we saw erythematous papules, vesicles, superficial erosions and crusts on all body regions, but especially on the trunk and in the main neck region. The patient was diagnosed with eczema herpeticum and he was treated with intravenous aciclovir 1000 mg 3 times a day (10 mg/kg 3 dd) and flucloxacillin 1000 mg 4 times a day for seven days.
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Aciclovir/administración & dosificación , Antivirales/administración & dosificación , Dermatitis Atópica/virología , Exantema/tratamiento farmacológico , Floxacilina/administración & dosificación , Erupción Variceliforme de Kaposi/tratamiento farmacológico , Adulto , Quimioterapia Combinada , Exantema/virología , Humanos , MasculinoRESUMEN
Patients with schizophrenia have a higher mortality risk than patients suffering from any other psychiatric disorder. Previous research is inconclusive regarding the association of antipsychotic treatment with long-term mortality risk. To this aim, we systematically reviewed the literature and performed a meta-analysis on the relationship between long-term mortality and exposure to antipsychotic medication in patients with schizophrenia. The objectives were to (i) determine long-term mortality rates in patients with schizophrenia using any antipsychotic medication; (ii) compare these with mortality rates of patients using no antipsychotics; (iii) explore the relationship between cumulative exposure and mortality; and (iv) assess causes of death. We systematically searched the EMBASE, MEDLINE and PsycINFO databases for studies that reported on mortality and antipsychotic medication and that included adults with schizophrenia using a follow-up design of more than 1 year. A total of 20 studies fulfilled our inclusion criteria. These studies reported 23,353 deaths during 821,347 patient years in 133,929 unique patients. Mortality rates varied widely per study. Meta-analysis on a subgroup of four studies showed a consistent trend of an increased long-term mortality risk in schizophrenia patients who did not use antipsychotic medication during follow-up. We found a pooled risk ratio of 0.57 (LL:0.46 UL:0.76 p value <0.001) favouring any exposure to antipsychotics. Statiscal heterogeneity was found to be high (Q = 39.31, I 2 = 92.37%, p value < 0.001). Reasons for the increased risk of death for patients with schizophrenia without antipsychotic medication require further research. Prospective validation studies, uniform measures of antipsychotic exposure and classified causes of death are commendable.
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Antipsicóticos/farmacología , Esquizofrenia/tratamiento farmacológico , Esquizofrenia/mortalidad , Antipsicóticos/efectos adversos , HumanosRESUMEN
OBJECTIVE/BACKGROUND: For decades acute lower limb deep venous thrombosis (DVT) has been subdivided into distal DVT (isolated to the calf veins) and proximal DVT (extending above calf vein level). The aim of this study was to analyse the anatomical site and extent of thrombus in a large cohort of patients with acute DVT. METHODS: A retrospective analysis of all patients aged >18 years, presenting with unilateral DVT according to duplex ultrasound investigation was performed at the University Hospital of Antwerp, Belgium (1994-2012). The anatomical site and extent of thrombus was registered and subdivided into five segments: calf veins (segment 1), popliteal vein (segment 2), femoral vein (segment 3), common femoral vein (segment 4), and iliac veins, with or without inferior vena cava (segment 5). RESULTS: The median age of the 1,338 patients (50% male) included was 62 years (range 18-98 years). Left sided DVT was predominant (57%). DVT was limited to one segment in 443 patients, of whom 370 had DVT isolated to the calf veins (28% of total cohort). In 968 patients with what was previously called "proximal DVT", the median number of affected segments was three (range 1-5 segments). In this group iliofemoral DVT (at least involving segment four and/or five) was present in 506 patients (38% of total cohort), whereas the remaining patients had femoropopliteal DVT (at least in segment two and/or three but not in four or five). Iliofemoral DVT without thrombus in segments one and two was present in 160 patients (12% of total cohort). CONCLUSION: This study illustrates the large diversity of thrombus distribution in patients previously described as having "proximal DVT". Therefore, this term should be abandoned and replaced with iliofemoral and femoropopliteal DVT. Patients with iliofemoral DVT (38%) could be considered for early clot removal; 12% of all patients with DVT would be ideal candidates for such intervention.
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Vena Femoral/diagnóstico por imagen , Vena Ilíaca/diagnóstico por imagen , Pierna/irrigación sanguínea , Vena Poplítea/diagnóstico por imagen , Ultrasonografía Doppler Dúplex/métodos , Trombosis de la Vena/diagnóstico por imagen , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto JovenRESUMEN
In tomato, Ve is implicated in race-specific resistance to infection by Verticillium species causing crop disease. Characterization of the Ve locus involved positional cloning and isolation of two closely linked inverted genes. Expression of individual Ve genes in susceptible potato plants conferred resistance to an aggressive race 1 isolate of Verticillium albo-atrum. The deduced primary structure of Ve1 and Ve2 included a hydrophobic N-terminal signal peptide, leucine-rich repeats containing 28 or 35 potential glycosylation sites, a hydrophobic membrane-spanning domain, and a C-terminal domain with the mammalian E/DXXXLphi or YXXphi endocytosis signals (phi is an amino acid with a hydrophobic side chain). A leucine zipper-like sequence occurs in the hydrophobic N-terminal signal peptide of Ve1 and a Pro-Glu-Ser-Thr (PEST)-like sequence resides in the C-terminal domain of Ve2. These structures suggest that the Ve genes encode a class of cell-surface glycoproteins with receptor-mediated endocytosis-like signals and leucine zipper or PEST sequences.
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Genes de Plantas/fisiología , Leucina Zippers , Glicoproteínas de Membrana/genética , Proteínas de Plantas/genética , Receptores de Superficie Celular/genética , Solanum lycopersicum/genética , Verticillium/fisiología , Secuencia de Aminoácidos , Clonación Molecular , Expresión Génica , Prueba de Complementación Genética , Genoma de Planta , Glicoproteínas de Membrana/fisiología , Datos de Secuencia Molecular , Proteínas de Plantas/fisiología , Plantas Modificadas Genéticamente , Receptores de Superficie Celular/fisiología , Solanum tuberosum/microbiologíaRESUMEN
A plant oleosin was used as a 'carrier' for the production of the leech anticoagulant protein, hirudin (variant 2). The oleosin-hirudin fusion protein was expressed and accumulated in seeds. Seed-specific expression of the oleosin-hirudin fusion mRNA was directed via an Arabidopsis oleosin promoter. The fusion protein was correctly targeted to the oil body membrane and separated from the majority of other seed proteins by flotation centrifugation. Recombinant hirudin was localized to the surface of oil bodies as determined by immunofluorescent techniques. The oleosin-hirudin fusion protein accumulated to ca. 1% of the total seed protein. Hirudin was released from the surface of the oil bodies using endoprotease treatment. Recombinant hirudin was partially purified through anion exchange chromatography and reverse-phase chromatography. Hirudin activity, measured in anti-thrombin units (ATU), was observed in seed oil body extracts, but only after the proteolytic release of hirudin from its oleosin 'carrier'. About 0.55 ATU per milligram of oil body protein was detected in cleaved oil body preparations. This activity demonstrated linear dose dependence. The oleosin fusion protein system provides a unique route for the large-scale production of recombinant proteins in plants, as well as an efficient process for purification of the desired polypeptide.
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Proteínas de Arabidopsis , Hirudinas/biosíntesis , Proteínas de Plantas/biosíntesis , Secuencia de Aminoácidos , Animales , Arabidopsis/genética , Secuencia de Bases , Brassica/genética , Brassica/metabolismo , Cartilla de ADN , ADN Complementario , Hirudinas/aislamiento & purificación , Hirudinas/farmacología , Sanguijuelas , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Regiones Promotoras Genéticas , Proteínas Recombinantes de Fusión/biosíntesis , Proteínas Recombinantes de Fusión/aislamiento & purificación , Proteínas Recombinantes de Fusión/farmacología , Semillas , Homología de Secuencia de Ácido Nucleico , Trombina/antagonistas & inhibidores , TransfecciónRESUMEN
We have investigated the protein domains responsible for the correct subcellular targeting of plant seed oleosins. We have attempted to study this targeting in vivo using "tagged" oleosins in transgenic plants. Different constructs were prepared lacking gene sequences encoding one of three structural domains of natural oleosins. Each was fused in frame to the Escherichia coli uid A gene encoding beta-glucuronidase (GUS). These constructs were introduced into Brassica napus using Agrobacterium-mediated transformation. GUS activity was measured in washed oil bodies and in the soluble protein fraction of the transgenic seeds. It was found that complete Arabidopsis oleosin-GUS fusions undergo correct subcellular targeting in transgenic Brassica seeds. Removal of the C-terminal domain of the Arabidopsis oleosin comprising the last 48 amino acids had no effect on overall subcellular targeting. In contrast, loss of the first 47 amino acids (N terminus) or amino acids 48 to 113 (which make up a lipophilic core) resulted in impaired targeting of the fusion protein to the oil bodies and greatly reduced accumulation of the fusion protein. Northern blotting revealed that this reduction is not due to differences in mRNA accumulation. Results from these measurements indicated that both the N-terminal and central oleosin domain are important for targeting to the oil body and show that there is a direct correlation between the inability to target to the oil body and protein stability.
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Proteínas de Arabidopsis , Arabidopsis/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Secuencia de Aminoácidos , Secuencia de Bases , Northern Blotting , Brassica , Escherichia coli , Genes Bacterianos , Genes de Plantas , Glucuronidasa/biosíntesis , Glucuronidasa/genética , Intrones , Datos de Secuencia Molecular , Mutagénesis Insercional , Aceites , Oligodesoxirribonucleótidos , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas , ARN de Planta/análisis , ARN de Planta/biosíntesis , Rhizobium , Semillas , Eliminación de Secuencia , Fracciones Subcelulares/metabolismoRESUMEN
Plant seeds frequently store oils (triglycerides) in discrete organelles called oil-bodies. These are normally surrounded by a phospholipid half-unit membrane equipped with specialized proteins called oleosins. Oleosins are highly lipophilic proteins, are expressed at high levels in many seeds and are specifically targeted to oil-bodies. We have investigated the potential of oleosins to act as carriers for recombinant proteins by the production of translational fusions between oleosins and genes encoding proteins foreign to plant cells. We have shown that a fusion comprising a complete oleosin coding domain and a beta-glucuronidase coding sequence may be expressed specifically in the seeds of the oilseed crop plant, Brassica napus, and its product is correctly targeted with approximately 80% of the activity partitioning with oil-bodies. Recombinant oil-bodies may be used to facilitate separation of a recombinant protein from other cellular proteins. Using this approach, the desired protein may be cleaved from the oil-bodies using an endoprotease and further purified. Alternatively, a fusion protein which is enzymatically active and resides on the oil-bodies may be used directly in heterogeneous catalysis. In this application, after a round of catalysis the oil-bodies may be recovered and re-used several times without loss of activity. Thus the oil-bodies act as an immobilization matrix. The fusion protein is stable in dry seeds for long periods and when extracted has a half-life of 3-4 weeks on oil-bodies. Finally, the production of these recombinant oil-bodies is extremely inexpensive, offering a novel route to the manufacture of recombinant proteins.
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Proteínas de Arabidopsis , Brassica , Orgánulos/metabolismo , Aceites de Plantas/metabolismo , Proteínas de Plantas/genética , Semillas/ultraestructura , Proteínas Portadoras , Estabilidad de Medicamentos , Glucuronidasa/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Proteínas Recombinantes de FusiónRESUMEN
Progressive deletions of the 5'-flanking sequences of an Arabidopsis oleosin gene were fused to beta-glucuronidase (GUS) and introduced into Brassica napus plants using Agrobacterium-mediated transformation. The effect of these deletions on the quantitative level of gene expression, organ specificity and developmental regulation was assessed. In addition, the influence of abscisic acid (ABA), jasmonic acid (JA), sorbitol and a combined ABA/sorbitol treatment on gene expression was investigated. Sequences that positively regulate quantitative levels of gene expression are present between -1100 to -600 and -400 to -200 of the promoter. In addition, sequences present between -600 and -400 down-regulate quantitative levels of expression. In transgenic B. napus plants, the oleosin promoter directs seed-specific expression of GUS which is present at early stages of seed development and increases throughout seed maturation. Sequences present between -2500 and -1100 of the promoter are involved in modulating the levels of expression at early stages of embryo development. Histochemical staining of embryos demonstrated that expression is uniform throughout the tissues of the embryo. Sequences involved in the response to ABA and sorbitol are present between -400 and -200. The induction of GUS activity by a combined ABA/sorbitol treatment is additive suggesting that ABA is not the sole mediator of osmotically induced oleosin gene expression. A response to JA was only observed when the oleosin promoter was truncated to -600 suggesting that the reported effect of JA on oleosin gene expression may be at a post-transcriptional level.
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Proteínas de Arabidopsis , Arabidopsis/genética , Brassica/genética , Genes de Plantas , Proteínas de Plantas/genética , Regiones Promotoras Genéticas , Ácido Abscísico/farmacología , Secuencia de Bases , Brassica/embriología , Brassica/metabolismo , Ciclopentanos/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Glucuronidasa/genética , Datos de Secuencia Molecular , Oxilipinas , Plantas Modificadas Genéticamente , Secuencias Reguladoras de Ácidos Nucleicos , Semillas/metabolismo , Eliminación de Secuencia , Sorbitol/farmacología , Transformación GenéticaRESUMEN
We tested the hypothesis that loose grass hay as a supplement to a pelleted diet reduces fur chewing in rabbits. Weanling rabbits (n = 315) were given one of three diets ad libitum: a control, pelleted diet, the pelleted diet containing 20% (wt/wt) hay meal or the pelleted diet plus loose hay. Fur chewing was assessed indirectly by blind scoring of the extent of alopecia in live rabbits and the amount of gastric hair after slaughter. Rabbits given either loose hay or the diet pellets containing hay displayed significantly less alopecia on the back and sides than control rabbits did. Loose hay, but not the pellets containing hay, completely prevented the development of alopecia on the forehead. The provision of loose hay as supplement to the control diet pellets significantly reduced the amount of gastric hair, whereas inclusion of hay meal into the pellets had no effect. It is concluded that supplemental loose hay prevents rabbits from pulling off fur from the forehead of cage mates. This effect of hay might be related to satisfaction of a craving for nibbling.
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Alimentación Animal , Conducta Animal , Conducta Alimentaria , Conejos , Animales , Bezoares , Sistema Digestivo , Cuerpos Extraños , CabelloAsunto(s)
Proteínas de Arabidopsis , Lipoproteínas/genética , Proteínas de Plantas/genética , Plantas/genética , Secuencia de Aminoácidos , Secuencia de Bases , Sitios de Unión/genética , Clonación Molecular , Lipoproteínas/química , Datos de Secuencia Molecular , Proteínas de Plantas/química , Secuencias Reguladoras de Ácidos Nucleicos/genética , Secuencias Repetitivas de Ácidos Nucleicos/genéticaRESUMEN
A number of treatments were tested for their ability to affect the synthesis of oilbody proteins in microspore-derived embryos of rapeseed (Brassica napus). Synthesis of the oilbody proteins was determined by [(35)S]methionine incorporation in vivo and sodium dodecyl sulfate-polyacrylamide gel electrophoresis of washed oilbody fractions. Oilbody proteins of approximately 19, 23, and 32 kilodaltons were found to be prominent. These proteins showed differential patterns of regulation. The 19 and 23 kilodalton proteins (oleosins) were greatly enhanced by treatments with abscisic acid, jasmonic acid, and osmotic stress imposed using sorbitol (12.5%). Synthesis of the 32 kilodalton protein was inhibited by abscisic acid and by sorbitol (12.5%), but unaffected by jasmonates. The strong promotion of synthesis of the 19 and 23 kilodalton oilbody proteins appeared to be specific as they are not seen with gibberellic acid treatment or with a stress such as heat shock. Time course experiments revealed that the abscisic acid stimulation of oleosin synthesis is quite rapid (less than 2 hours), reaching a maximum at 6 to 8 hours. The response of the oleosins to abscisic acid is found in all stages of embryogenesis, with a major increase in synthetic rates even in globular embryos on abscisic acid treatment. This suggests that these proteins may accumulate much earlier in embryogenesis than has previously been believed. The 32 kilodalton oilbody-associated protein appears different from the oleosins in several ways, including its distinct pattern of regulation and its unique property, among the oilbody proteins, of undergoing phosphorylation.
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A number of effects on embryogenesis of the putative phytohormone jasmonic acid (JA), and its methyl ester (MeJA), were investigated in two oilseed plants, repeseed (Brassica napus) and flax (Linum usitatissimum). Results from treatments with JA and MeJA were compared with those of a known effector of several aspects of embryogenesis, abscisic acid (ABA). Jasmonic acid was identified by gas chromatography-mass spectrometry as a naturally occurring substance in both plant species during embryo development. Both JA and MeJA can prevent precocious germination of B. napus microspore embryos and of cultured zygotic embryos of both species at an exogenous concentration of >1 micromolar. This dose-response was comparable with results obtained with ABA. Inhibitory effects were also observed on seed germination with all three growth regulators in rapeseed and flax. A number of molecular aspects of embryogenesis were also investigated. Expression of the B. napus storage protein genes (napin and cruciferin) was induced in both microspore embryos and zygotic embryos by the addition of 10 micromolar JA. The level of napin and cruciferin mRNA detected was similar to that observed when 10 micromolar ABA was applied to these embryos. For MeJA only slight increases in napin or cruciferin mRNA were observed at concentrations of 30 micromolar. Several oilbody-associated proteins were found to accumulate when the embryos were incubated with either JA or ABA in both species. The MeJA had little effect on oilbody protein synthesis. The implications of JA acting as a natural regulator of gene expression in zygotic embryogenesis are discussed.
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The gene encoding cytochrome c553 from Desulfovibrio vulgaris Hildenborough was cloned by using two synthetic deoxyoligonucleotide probes. The amino acid sequence derived from the sequence of the gene differs from that reported by Bruschi and LeGall (Biochim. Biophys. Acta 271:48-60, 1972). Renewed protein sequencing confirmed the correctness of the DNA-derived sequence. The gene sequence indicates cytochrome c553 to be synthesized as a precursor protein with an NH2-terminal signal sequence of 24 residues.
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Grupo Citocromo c/genética , Desulfovibrio/genética , Secuencia de Aminoácidos , Secuencia de Bases , Southern Blotting , Clonación Molecular , Genes Bacterianos , Datos de Secuencia Molecular , Señales de Clasificación de Proteína/genética , Mapeo RestrictivoRESUMEN
The antihypertensive effects of atenolol and propranolol were compared in a double-blind crossover study of 19 patients with essential hypertension (World Health Organization, I and II) who were receiving long-term diuretic treatment (chlorthalidone, 50 mg daily) during the study. After a 3-wk placebo period, a beta-adrenergic antagonist was administered once daily (atenolol, 50 mg daily, or propranolol, 80 mg daily) for a week. If the MAP was more than 108 mm Hg at the end of the week, dosage of the beta-blocker was doubled the following week; when necessary, doubling was repeated to a maximum dose of 640 mg propranolol and 400 mg atenolol daily. Fifty milligrams atenolol had a greater effect than 80 mg propranolol and was as effective as 160 mg propranolol. The dose-response curve flattened off after 160 mg propranolol and 50 mg atenolol daily. The two highest doses of atenolol lowered MAP more than the highest doses of propranolo. Heart rate slowing was the same for both drugs and did not correlate with the fall in blood pressure. PRA was suppressed by all doses of propranolol, whereas atenolol suppressed PRA only at the 2 highest doses, (200 and 400 mg daily). With the lower propranolol doses, the percent MAP change correlated weakly with the percent PRA change (80 mg--r = 0.41, p less than 0.1; 160 mg--r = 0.64, p less than 0.05). Side effects were minimal, and were noted only with 640 mg propranolol; with this exception, the percentage of patients with no complaints rose when placebo was replaced by beta-blockers.