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BACKGROUND: Non-specific lipid transfer proteins (nsLTP) are considered to provoke allergic symptoms to plane tree pollen, which are frequently associated with peach allergy. OBJECTIVE: The objective was to clone the cDNA of plane pollen nsLTP Pla a 3, to characterize IgE-binding and allergenic potency of recombinant Pla a 3 in comparison to its natural counterpart and peach nsLTP Pru p 3. METHODS: Natural Pla a 3 was purified from plane pollen and analysed by mass spectrometry (MS). Recombinant Pla a 3 was characterized by SDS-PAGE and CD spectroscopy. Specific IgE to extract, components of plane pollen and Pru p 3 was measured by ImmunoCAP in sera of patients allergic to either plane pollen (n = 10), peach (n = 15) or both (n = 15). Biological potency of the proteins was investigated by in vitro mediator release assays and IgE cross-reactivity by competitive ELISA. RESULTS: Two Pla a 3 isoforms were identified. Recombinant Pla a 3 showed high purity, structural integrity, IgE-binding capacity comparable to nPla a 3 and biological potency. Sensitization to plane pollen extract was confirmed in 24/25 plane pollen allergics. The frequency of sensitization to Pla a 3 was 53% among patients allergic to both plane pollen and peach and 10% among plane pollen allergics tolerating peach where most patients were sensitized to Pla a 1. Pla a 3 and Pru p 3 showed strong bi-directional IgE cross-reactivity in patients allergic to peach and plane pollen, but not in peach allergics tolerating plane pollen. Levels of IgE-binding were generally higher to Pru p 3 than to Pla a 3. CONCLUSION: Sensitization to Pla a 3 is relevant in a subgroup of plane pollen allergics with concomitant peach allergy. IgE testing with Pla a 3 may serve as a marker to identify plane pollen allergic patients at risk of LTP-mediated food reactions and thereby improve in vitro diagnostic procedures.
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Alérgenos/imunologia , Antígenos de Plantas/genética , Antígenos de Plantas/imunologia , Clonagem Molecular , Hipersensibilidade Alimentar/diagnóstico , Hipersensibilidade Alimentar/imunologia , Prunus persica/efeitos adversos , Sequência de Aminoácidos , Antígenos de Plantas/química , Biomarcadores , Reações Cruzadas/imunologia , Expressão Gênica , Liberação de Histamina , Humanos , Imunização , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Fenótipo , Pólen/imunologia , Isoformas de Proteínas , Proteínas RecombinantesRESUMO
BACKGROUND: Stereotactic ablative body radiotherapy (SBRT, SABR) is being increasingly applied because of its high local efficacy, e.g., for small lung tumors. However, the optimum dosage is still under discussion. Here, we report data on 45 lung lesions [non-small cell lung cancer (NSCLC) or metastases] in 39 patients treated between 2009 and 2010 by SABR. PATIENTS AND METHODS: SABR was performed with total doses of 35 Gy (5 fractions) or 37.5 Gy (3 fractions) prescribed to the 60% isodose line encompassing the planning target volume. Three-monthly follow-up CT scans were supplemented by FDG-PET/CT if clinically indicated. RESULTS: The median follow-up was 17 months. Local progression-free survival rates were 90.5% (all patients), 95.0% (NSCLC), and 81.8% (metastases) at 1 year. At 2 years, the respective local progression-free survival rates were 80.5%, 95.0%, and 59.7%. Overall survival rates were 71.1% (all patients), 65.4% (NSCLC), and 83.3% (metastases) at 1 year. Overall survival rates at 2 years were 52.7%, 45.9%, and 66.7%, respectively. Acute side effects were mild. CONCLUSION: With the moderate dose schedule used, well-tolerated SABR led to favorable local tumor control as in other published series. Standardization in reporting the dose prescription for SABR is needed to allow comparison of different series in order to determine optimum dosage.
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Carcinoma Pulmonar de Células não Pequenas/cirurgia , Neoplasias Pulmonares/secundário , Neoplasias Pulmonares/cirurgia , Radiocirurgia/métodos , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Medidas de Volume Pulmonar , Masculino , Pessoa de Meia-Idade , Imagem Multimodal , Estadiamento de Neoplasias , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios XRESUMO
BACKGROUND: A basis for future trials with stereotactic body radiotherapy (SBRT) for tumors of the liver hilum should be established. Thus, dosage concepts, planning processes, and dose constraints as well as technical innovations are summarized in this contribution. METHODS: On the background of our own data, the current literature was reviewed. The use of SBRT in the most common tumors of the liver hilum (pancreatic cancer and Klatskin tumors) was investigated. Dose constraints were calculated in 2 Gy standard fractionation doses. RESULTS: A total of 8 pilot or phase I/II studies about SBRT in the liver hilum were identified. In recent years, the SBRT technique has developed very quickly from classical stereotactic body frame radiotherapy to IGRT techniques including gating and tracking systems. In the studies using classical body frame technique, patients experienced considerable toxicities (duodenal ulcer/perforation) as compared to tolerable side effects in IGRT studies (<10% grade 3 and 4 toxicities). Dose constraints for duodenum, liver, kidneys, colon, and spinal cord were derived from the investigated studies. Survival and local tumor control data are very heterogeneous: median survival in these patients with locally advanced pancreatic or Klatskin tumors ranges between 5 and 32 months. Excellent local tumor control rates of about 80% over 24 months were achieved using SBRT. CONCLUSION: Despite a few negative results, SBRT seems to be a promising technique in the treatment of tumors of the liver hilum. Highest precision in diagnostics, positioning, and irradiation as well as strict dose constraints should be applied to keep target volumes as small as possible and side effects tolerable.
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Neoplasias dos Ductos Biliares/cirurgia , Ducto Hepático Comum , Tumor de Klatskin/cirurgia , Fígado/cirurgia , Neoplasias Pancreáticas/cirurgia , Complicações Pós-Operatórias/etiologia , Radiocirurgia/métodos , Radiocirurgia/tendências , Neoplasias dos Ductos Biliares/mortalidade , Neoplasias dos Ductos Biliares/patologia , Ensaios Clínicos Fase I como Assunto , Ensaios Clínicos Fase II como Assunto , Seguimentos , Tumor de Klatskin/mortalidade , Tumor de Klatskin/patologia , Fígado/patologia , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Projetos Piloto , Taxa de SobrevidaRESUMO
Hemorrhagic transformation of ischemic stroke has devastating consequences, with high mortality and poor functional outcomes. Animal models of ischemic stroke also demonstrate the potential for hemorrhagic transformation, which complicates biochemical characterization, treatment studies, and hinders poststroke functional outcomes in affected subjects. The incidence of hemorrhagic transformation of ischemic stroke in animal model research is not commonly reported. The postmortem brain of such cases presents a complex milieu of biomarkers due to the presence of healthy cells, regions of varying degrees of ischemia, dead and dying cells, dysregulated metabolites, and blood components (especially reactive Fe species released from lysed erythrocytes). To improve the characterization of hemorrhage biomarkers on an ischemic stroke background, we have employed a combination of histology, X-ray fluorescence imaging (XFI), and Fourier transform infrared (FTIR) spectroscopic imaging to assess 122 photothrombotic (ischemic) stroke brains. Rapid freezing preserves brain biomarkers in situ and minimizes metabolic artifacts due to postmortem ischemia. Analysis revealed that 25% of the photothrombotic models had clear signs of hemorrhagic transformation. The XFI and FTIR metabolites provided a quantitative method to differentiate key metabolic regions in these models. Across all hemorrhage cases, it was possible to consistently differentiate otherwise healthy tissue from other metabolically distinct regions, including the ischemic infarct, the ischemic penumbra, blood vessels, sites of hemorrhage, and a region surrounding the hemorrhage core that contained elevated lipid oxidation. Chemical speciation of deposited Fe demonstrates the presence of heme-Fe and accumulation of ferritin.
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Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Animais , Biomarcadores , Isquemia Encefálica/complicações , Isquemia Encefálica/diagnóstico por imagem , Hemorragia/complicações , Humanos , AVC Isquêmico/diagnóstico por imagem , Imagem Multimodal , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/epidemiologiaRESUMO
Lupin cultivation worldwide is threatened by anthracnose, a destructive disease caused by the seed- and air-borne fungal pathogen Colletotrichum lupini. In this study we explored the intraspecific diversity of 39 C. lupini isolates collected from different lupin cultivating regions around the world, and representative isolates were screened for their pathogenicity and virulence on white and Andean lupin. Multi-locus phylogeny and morphological characterizations showed intraspecific diversity to be greater than previously shown, distinguishing a total of six genetic groups and ten distinct morphotypes. Highest diversity was found across South America, indicating it as the center of origin of C. lupini. The isolates that correspond to the current pandemic belong to a genetic and morphological uniform group, were globally widespread, and showed high virulence on tested white and Andean lupin accessions. Isolates belonging to the other five genetic groups were mostly found locally and showed distinct virulence patterns. Two highly virulent strains were shown to overcome resistance of advanced white lupin breeding material. This stresses the need to be careful with international seed transports in order to prevent spread of currently confined but potentially highly virulent strains. This study improves our understanding of the diversity, phylogeography and pathogenicity of a member of one of the world's top 10 plant pathogen genera, providing valuable information for breeding programs and future disease management.
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Colletotrichum , Variação Genética , Lupinus/microbiologia , Doenças das Plantas , Fatores de Virulência/genética , Colletotrichum/genética , Colletotrichum/patogenicidade , Doenças das Plantas/genética , Doenças das Plantas/microbiologiaRESUMO
BACKGROUND: In a prospective clinical study the topical use of a polysaccharide-containing spray for the treatment of xerostomia after radiotherapy in the head and neck area was tested. PATIENTS AND METHODS: A total of 83 patients (evaluable return: n=55) with xerostomia after radiotherapy in the head and neck area received a pump spray with 50 ml Saliva natura (medac, Wedel, Germany) to test for 1 week. The patients were asked to fill in a questionnaire about their xerostomia with and without use of the spray. Individual items included: xerostomia in the state of rest, difficulties speaking, eating and sleeping, frequency of the use of treatment against xerostomia, changes in taste, and saliva viscosity. Additionally, they assessed the spray in general and for taste. RESULTS: Patients reported an improvement in all areas included in the questionnaire. The greatest effect of the spray was seen in sleeping difficulties, which improved by almost a whole point from 3.65 to 2.67, as well as in the frequency of use of xerostomia treatment (averagely 15x/day without and 10x/day with the spray). On average the spray was graded as "satisfactory" (3.09), while its taste was graded as "good" (2.17). CONCLUSION: The tested spray may help improve the situation of patients with xerostomia following radiotherapy in the head and neck area. These patients should be given the opportunity to test a spray of this kind.
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Mucinas/administração & dosagem , Lesões por Radiação/tratamento farmacológico , Lesões por Radiação/etiologia , Radioterapia Conformacional/efeitos adversos , Saliva Artificial/administração & dosagem , Xerostomia/tratamento farmacológico , Xerostomia/etiologia , Administração por Inalação , Adulto , Aerossóis/administração & dosagem , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Xerostomia/diagnósticoRESUMO
A photo-elastic modulator based 25-chord motional Stark effect (MSE) diagnostic has been successfully developed and commissioned in Korea Superconducting Tokamak Advanced Research. The diagnostic measures the radial magnetic pitch angle profile of the Stark splitting of a D-alpha line at 656.1 nm by the electric field associated with the neutral deuterium heating beam. A tangential view of the neutral beam provides a good spatial resolution of 1-3 cm for covering the major radius from 1.74 m to 2.28 m, and the time resolution is achieved at 10 ms. An in-vessel calibration before the vacuum closing as well as an in situ calibration during the tokamak operation was performed by means of specially designed polarized lighting sources. In this work, we present the final design of the installed MSE diagnostic and the first results of the commissioning.
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OBJECTIVES: To evaluate indications for and outcome of perineal urethrostomy in cats. METHODS: The medical records of 59 cats that had undergone perineal urethrostomy were evaluated. Short-term follow up information (for a period of four weeks following surgery) was available for all of the cats. Long-term follow up information (for a period of at least four months) was available for 39 cats. RESULTS: Early complications occurred in 25.4 per cent of cats and late complications were observed in 28.2 per cent of cats. The most frequent late complication was recurring bacterial urinary tract Infection. CLINICAL SIGNIFICANCE: Despite frequent complications and recurring signs of lower urinary tract disease, 32.2 per cent of the cats had a disease-free long-term outcome (mean four years, median 3.9 years), and 88.6 per cent of clients interviewed thought that their cats had a good quality of life after surgery.
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Doenças do Gato/cirurgia , Uretra/cirurgia , Doenças Uretrais/veterinária , Derivação Urinária/veterinária , Animais , Gatos , Masculino , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/veterinária , Qualidade de Vida , Recidiva , Estudos Retrospectivos , Resultado do Tratamento , Doenças Uretrais/cirurgia , Derivação Urinária/métodos , Infecções Urinárias/epidemiologia , Infecções Urinárias/etiologia , Infecções Urinárias/veterináriaRESUMO
ABSTRACT A major leaf rust (Puccinia triticina) resistance quantitative trait locus (QTL) (QLrP.sfr-7DS) previously has been described on chromosome 7DS in the winter wheat (Triticum aestivum) cv. Forno. It was detected in a population of single-seed descent (SSD) lines derived from the cross Arina x Forno. QLrP.sfr-7DS conferred a durable and slow-rusting resistance phenotype, co-segregated with a QTL for leaf tip necrosis (LTN) and was mapped close to Xgwm295 at a very similar location as the adult plant leaf rust resistance gene Lr34 found in some spring wheat lines. Here, we describe the validation of this QTL by mapping it to the same chromosomal region close to Xgwm295 on chromosome 7DS in a population of SSD lines from the winter wheat x spelt (T. spelta) cross Forno x Oberkulmer. In both populations, the log of the likelihood ratio curves for leaf rust resistance and LTN peaked at identical or very similar locations, indicating that both traits are due to the same gene. We have improved the genetic map in the target region of QLrP.sfr-7DS using microsatellite and expressed sequence tag (EST) markers. Two EST loci (Xsfr.BF473324 and Xsfr.BE493812) define a genetic interval of 7.6 centimorgans containing QLrP.sfr-7DS, a considerably more precise genetic location for this QTL than previously described both in spring and winter wheat. The identified genetic interval is physically located in the distal 39% of chromosome 7DS. Single-marker analysis identified Xsfr.BF473324 and Xgwm1220 as the most informative loci for QLrP.sfr-7DS and QLtn.sfr-7DS. In the rice genome, the two ESTs flanking the QLrP.sfr-7DS/QLtn.sfr-7DS chromosomal segment in wheat are conserved on chromosome 6S in a region colinear with wheat chromosome 7DS. There, they define a physical region of three rice bacterial artificial chromosomes spanning approximately 300 kb.
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Soluble extracts from young bovine, human, rat and rabbit lenses were fractionated by high resolution size-exclusion chromatography to demonstrate the existence of three discrete size-classes of monomeric crystallins in each species. These were identified by ion exchange chromatography, amino acid analysis, SDS electrophoresis and isoelectric focusing as the beta s-, gamma A- and gamma B-crystallins. Conventional SDS electrophoretic analysis of these proteins revealed apparent Mr values of about 23kD, 22kD and 19kD, respectively. Similar analysis in the presence of 6 M urea showed the proteins all co-migrated with an apparent Mr of about 20,500, which is far more consistent with the molecular weights calculated from beta s- and gamma-crystallin sequence data. Amino acid compositions of all the beta s samples indicate a high degree of homology to the bovine protein, whose sequence is known. The different species beta s-crystallins showed other general similarities in size, charge, thiol content and secondary structural properties. On the other hand, near UV CD and fluorescence emission and energy transfer measurements indicate that these proteins have subtle yet significant differences in their tertiary structures. Unlike the gamma-crystallins, the secondary structure of all of the beta s samples is completely denatured in the presence of 8 M urea at 20 degrees C.
Assuntos
Cristalinas/isolamento & purificação , Cristalino/análise , Aminoácidos/análise , Animais , Bovinos , Cromatografia por Troca Iônica , Dicroísmo Circular , Cristalinas/análise , Eletroforese em Gel de Poliacrilamida , Humanos , Lactente , Focalização Isoelétrica , Coelhos , Ratos , Ratos EndogâmicosRESUMO
An 18-month-old female crossbred dog was presented with a unilateral sacroiliac luxation and separation of the pelvic symphysis. Surgical correction of the luxation with screw fixation led to entrapment of the urethra between the symphyseal parts of the two hemipelves.
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Cães/lesões , Fixação Interna de Fraturas/veterinária , Ossos Pélvicos/lesões , Uretra/lesões , Uretra/cirurgia , Animais , Feminino , Fixação Interna de Fraturas/efeitos adversos , Ossos Pélvicos/cirurgia , Cirurgia VeterináriaRESUMO
This report describes a rare case of bicipital tenosynovitis in a Maine coon cat. The cat, a three-and-half-year-old neutered female, presented with chronic weightbearing lameness of the left forelimb. Flexion of the left glenohumeral joint and extension of the left cubital joint were resented, and palpation of the biceps brachii tendon in the bicipital groove elicited pain. A mild incongruity of the joint with mild degenerative changes was seen radiographically. Glenohumeral joint dysplasia was suspected. Ultrasound examination revealed marked thickening of the bicipital tendon and moderate effusion of the left bicipital tendon sheath. Positive contrast radiography of the joint confirmed dilation of the tendon sheath. A tentative diagnosis of bicipital tenosynovitis was made and confirmed on arthrotomy. Surgical removal of osteophytes resulted in the cat being free from pain but a mild lameness recurred six months after surgery.
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Doenças do Gato/diagnóstico , Tenossinovite/veterinária , Animais , Artralgia/etiologia , Artralgia/cirurgia , Artralgia/veterinária , Doenças do Desenvolvimento Ósseo/diagnóstico por imagem , Doenças do Desenvolvimento Ósseo/cirurgia , Doenças do Desenvolvimento Ósseo/veterinária , Doenças do Gato/diagnóstico por imagem , Doenças do Gato/cirurgia , Gatos , Feminino , Coxeadura Animal/etiologia , Coxeadura Animal/cirurgia , Radiografia , Recidiva , Articulação do Ombro/diagnóstico por imagem , Articulação do Ombro/patologia , Tendões/diagnóstico por imagem , Tendões/patologia , Tenossinovite/diagnóstico , Tenossinovite/diagnóstico por imagem , Resultado do Tratamento , UltrassonografiaRESUMO
Breeding for wheat varieties resistant to Stagonospora nodorum blotch (SNB) is the most sustainable strategy for controlling the disease. In order to map quantitative trait loci (QTLs) for SNB resistance we analysed 204 recombinant inbred lines of the cross between the winter wheat (Triticum aestivum L.) variety Forno and the winter spelt (Triticum spelta L.) variety Oberkulmer. We determined the level of resistance of adult plants to leaf blotch (SNL) and glume blotch (SNG) as well as morphological traits for 2 years after artificial inoculation with S. nodorum. Using composite interval mapping and LOD > 3.7, we detected ten QTLs for SNG blotch resistance (six inherited from the susceptible parent Forno) and 11 QTLs for SNL resistance (four inherited from Forno) across 2 years. Both resistance traits were moderately correlated (r = 0.52) and had only one common QTL. For SNL resistance, seven QTLs were not associated with QTLs for morphological traits. Among them, QSnl.eth-2D, QSnl.eth-4B and QSnl.eth-7B3 had major effects (R(2) > 13%) and were potential candidates for marker-assisted selection. For SNG, the major QTL on chromosome 5A, explaining 36% of the phenotypic variance for resistance, was associated with the q locus conferring the spelt morphology (long lax ear, long culm and hard glumes). Only QSng.eth-1BS, which explained 7% of the variance for resistance to SNG blotch, was not associated with QTLs for morphological traits. The consequences for breeding programmes are discussed.
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Ascomicetos , Hibridização Genética , Imunidade Inata/genética , Fenótipo , Doenças das Plantas/microbiologia , Triticum/genética , Análise de Variância , Cruzamento/métodos , Mapeamento Cromossômico , Escore Lod , Doenças das Plantas/genética , Locos de Características Quantitativas , Suíça , Triticum/anatomia & histologiaRESUMO
To gain insight into the molecular features of the high-molecular-weight (HMW) fraction of soluble lens proteins and their changes in aging, we isolated this fraction from the nucleus of calf and cow lenses and measured fluorescence and circular dichroism (CD) properties of the samples. Not only was there an increase in the HMW fraction in the older lens, but there was also an age-related difference in tertiary structure that was clearly manifested in the fluorescence and CD parameters. The far-u.v. CD of low- and high-molecular-weight proteins do not differ significantly in band position and magnitude, but the near-u.v. CD of HMW protein does differ distinctly from that of all other crystallins (alpha, beta and gamma); the entire CD spectrum of this protein is displayed in the negative region. Millipore filtration further revealed that HMW aggregates are essentially a polydisperse population of different conformation (tertiary structure) and that these aggregates are associated by non-convalent interactions. This association is caused mainly by the apolar (hydrophobic) nature of the constituent protein. alpha-Crystallin has more hydrophobic domain along the peptide chain that do other crystallins and thus is likely to be the predominant protein in HMW aggregates.
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Cristalinas/análise , Envelhecimento/metabolismo , Animais , Bovinos , Dicroísmo Circular , Peso Molecular , Conformação Proteica , Desnaturação Proteica , Espectrometria de FluorescênciaRESUMO
Despite the low incidence of the acute porphyrias, a profound knowledge of the disease is essential for anaesthesiologists, as a variety of perioperatively administered drugs are potential triggers of an acute attack. There is an ongoing discussion about the use of volatile anaesthetics in porphyrias, but halothane and isoflurane seem to be safe. There is no clinical data or case report about the use of desflurane in this specific patient group, but its fast and relatively unchanged elimination and the minimal induction of the cytochrome P 450 system seem to be favorable in this setting. We report the use of desflurane in a patient with acute intermittent porphyria, scheduled for hemihepatectomy. To minimize perioperative distress by pain or the need for postoperative mechanical ventilation, we chose a balanced anaesthesia technique with desflurane, sufentanil and atracurium in combination with a continuous epidural analgesia (bupivacain and fentanyl) for the postoperative period. Preoperatively the porphyrin precursors were analyzed in serum and urine and postoperatively the 24 h-urine was screened every 2 days until postoperative day 6 to monitor the porphyria activity. The preoperative data showed high concentrations of porphyrin precursor excretion, confirming the diagnosis of AIP. The postoperative data in the 24 h-urine were significantly lower than preoperative levels and reached normal levels at postoperative day 5. There were no clinical symptoms of a porphyric attack during the postoperative hospitalization. The patient was discharged on postoperative day 21 in excellent condition. We conclude that our perioperative management prevented an acute porphyric attack in this case. Desflurane might be a valuable alternative to other hypnotics in patients with AIP.
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Anestesia Geral/efeitos adversos , Anestésicos Inalatórios/efeitos adversos , Isoflurano/análogos & derivados , Isoflurano/efeitos adversos , Porfiria Aguda Intermitente/complicações , Idoso , Desflurano , Feminino , Hepatectomia , Humanos , Porfirinas/sangue , Porfirinas/urinaRESUMO
The metabolism of dichloromethane by Dehalobacterium formicoaceticum in cell suspensions and crude cell extracts was investigated. The organism is a strictly anaerobic gram-positive bacterium that utilizes exclusively dichloromethane as a growth substrate and ferments this compound to formate and acetate in a molar ratio of 2:1. When [C]dichloromethane was degraded by cell suspensions, formate, the methyl group of acetate, and minor amounts of methanol were labeled, but there was no nuclear magnetic resonance signal corresponding to the carboxyl group of acetate. This finding and previously established carbon and electron balances suggested that dichloromethane was converted to methylene tetrahydrofolate, of which two-thirds was oxidized to formate while one-third gave rise to acetate by incorporation of CO(2) from the medium in the acetyl coenzyme A synthase reaction. When crude desalted extracts were incubated in the presence of dichloromethane, tetrahydrofolate, ATP, methyl viologen, and molecular hydrogen, dichloromethane and tetrahydrofolate were consumed, with the concomitant formation of stoichiometric amounts of methylene tetrahydrofolate. The in vitro transfer of the methylene group of dichloromethane onto tetrahydrofolate required substoichiometric amounts of ATP. The reaction was inhibited in a light-reversible fashion by 20 muM propyl iodide, thus suggesting involvement of a Co(I) corrinoid in the anoxic dehalogenation of dichloromethane. D. formicoaceticum exhibited normal growth with 0.8 mM sodium in the medium, and crude extracts contained ATPase activity that was partially inhibited by N,N'-dicyclohexylcarbodiimide and azide. During growth with dichloromethane, the organism thus may conserve energy not only by substrate-level phosphorylation but also by a chemiosmotic mechanism involving a sodium-independent F(0)F(1)-type ATP synthase.
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The aim of this project was to establish RAPD markers to determine the percentage of sexual off-spring of the facultative apomictic plant species H. perforatum. We did reciprocal crosses between four different accessions (A x B, B x A, C x D, D x C) by mechanical emasculation and hand pollination. Genomic DNA of the parents and the off-spring was isolated and PCR conditions were optimized in order to obtain reproducible bands with RAPD markers. Of the 260 screened RAPD primers 127 revealed polymorphism between the parental lines of A and B, whereas 53 revealed no amplification products. Each progeny was tested for the presence of paternal bands with three primers. We found no sexual off-spring among the 22 progenies of A x B, the nine progenies of B x A and the ten progenies of D x C. However, we detected six sexual off-spring among the 45 progenies of C x D. We have proved that RAPD markers can be used to distinguish between sexual and apomictic off-spring in H. perforatum and that sexual off-spring can be obtained from intraspecific crosses. The percentage of sexual progeny might depend on the genotype of the parental lines.
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DNA/análise , Hypericum/genética , Plantas Medicinais/genética , Técnica de Amplificação ao Acaso de DNA Polimórfico/métodos , Sequência de Bases , Cruzamentos Genéticos , Marcadores Genéticos , Genótipo , Medicina Tradicional Chinesa , Fitoterapia , Reação em Cadeia da Polimerase , Polimorfismo Genético , Especificidade da EspécieRESUMO
The objective of this study was to characterize the leaf rust resistance locus Lr1 in wheat. Restriction fragment length polymorphism (RFLP) analysis was performed on the resistant line Lr1/6* Thatcher and the susceptible varieties Thatcher and Frisal, as well as on the segregating F2 populations. Seventeen out of 37 RFLP probes mapping to group 5 chromosomes showed polymorphism between Lr1/6* Thatcher and Frisal, whereas 11 probes were polymorphic between the near-isogenic lines (NILs) Lr1/6* Thatcher and Thatcher. Three of these probes were linked to the resistance gene in the segregating F2 populations. One probe (pTAG621) showed very tight linkage to Lr1 and mapped to a single-copy region on chromosome 5D. The map location of pTAG621 at the end of the long arm of chromosome 5D was confirmed by the absence of the band in the nulli-tetrasomic line N5DT5B of Chinese Spring and a set of deletion lines of Chinese Spring lacking the distal part of 5DL. Twenty-seven breeding lines containing the Lr1 resistance gene in different genetic backgrounds showed the same band as Lr1/6* Thatcher when hybridized with pTAG621. The RFLP marker was converted to a sequence-tagged-site marker using polymerase chain reaction (PCR) amplification. Sequencing of the specific fragment amplified from both NILs revealed point mutations as well as small insertion/deletion events. These were used to design primers that allowed amplification of a specific product only from the resistant line Lr1/6* Thatcher. This STS, specific for the Lr1 resistance gene, will allow efficient selection for the disease resistance gene in wheat breeding programmes. In addition, the identification of a D-genome-specific probe tightly linked to Lr1 should ultimately provide the basis for positional cloning of the gene.
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DNA de Plantas/genética , Imunidade Inata/genética , Triticum/genética , Alelos , Sequência de Bases , Mapeamento Cromossômico , Dados de Sequência Molecular , Alinhamento de Sequência , Análise de SequênciaRESUMO
Fusarium head blight (FHB) of wheat is a widespread and destructive disease which occurs in humid and semi-humid areas. FHB epidemics can cause serious yield and quality losses under favorable climatic conditions, but the major concern is the contamination of grains with mycotoxins. Resistance to FHB is quantitatively inherited and greatly influenced by the environment. Its evaluation is costly and time-consuming. The genetic basis of FHB resistance has mainly been studied in spring wheat. The objective of this study was to map quantitative trait loci (QTLs) for resistance to FHB in a population of 240 recombinant inbred lines (RILs) derived from a cross between the two Swiss winter wheat cultivars Arina (resistant) and Forno (susceptible). The RILs were genotyped with microsatellite and RFLP markers. The resulting genetic map comprises 380 loci and spans 3,086 cM. The 240 RILs were evaluated for resistance to FHB in six field trials over 3 years. Composite interval mapping (CIM) analyses carried out on FHB AUDPC (i.e. mean values across six environments) revealed eight QTLs which altogether explained 47% of the phenotypic variance. The three main QTLs were mapped on the long arms of chromosomes 6D ( R(2)=22%), 5B ( R(2)=14%) and 4A ( R(2)=10%). The QTL detected on 5B originated from the susceptible parent Forno. Other QTLs with smaller effects on FHB resistance were detected on chromosomes 2AL, 3AL, 3BL, 3DS and 5AL.