RESUMO
We report the best limit on coherent elastic scattering of electron antineutrinos emitted from a nuclear reactor off germanium nuclei. The measurement was performed with the CONUS detectors positioned at 17.1 m from the 3.9 GW_{th} reactor core of the nuclear power plant in Brokdorf, Germany. The antineutrino energies of less than 10 MeV assure interactions in the fully coherent regime. The analyzed dataset includes 248.7 kg d with the reactor turned on and background data of 58.8 kg d with the reactor off. With a quenching parameter of k=0.18 for germanium, we determined an upper limit on the number of neutrino events of 85 in the region of interest at 90% confidence level. This new CONUS dataset disfavors quenching parameters above k=0.27, under the assumption of standard-model-like coherent scattering of the reactor antineutrinos.
RESUMO
Ornithine-oxo-acid aminotransferase (EC 2.6.1.13) from rat kidney was prepared as a single homogeneous protein as judged by polyacrylamide gel electrophoresis, ultracentrifuge analysis and double diffusion precipitin test. Content of pyridoxal phosphate, light absorption spectra, circular dicroism spectra, Km values, inhibitors, and electrophoretic mobilities of the proteins after reactions with group modifying reagents were similar for the ornithine-oxo-acid aminotransferases of rat kidney and liver. Rates of reaction with group modifying reagents, stabilities to storage at -15 degrees C, and stabilities to temperatures above 55 degrees C differed significantly for the two enzymes. The liver enzyme contained two more cysteine residues than the kidney enzyme as determined by three different methods. Heating the liver enzyme at 66-67 degrees C at pH 5.9 for 1 h decreased the thiol groups titratable by 5,5'-dithio-bis(2-nitrobenzoic acid) (Nbs2). Uncer the same conditions titratable thiol groups of the kidney enzyme were not decreased. Amino acid analysis revealed probably significant differences in tyrosine and isoleucine content in addition to cysteine. It was concluded that the primary structures of ornithine-oxo-acid aminotransferases of rat liver and kidney are not fully identical.
Assuntos
Rim/enzimologia , Fígado/enzimologia , Ornitina-Oxo-Ácido Transaminase/metabolismo , Transaminases/metabolismo , Aminoácidos/análise , Animais , Canavanina/farmacologia , Cisteína/análise , Ácidos Cetoglutáricos/farmacologia , Cinética , Peso Molecular , Ornitina/farmacologia , Ornitina-Oxo-Ácido Transaminase/imunologia , Ornitina-Oxo-Ácido Transaminase/isolamento & purificação , Fosfato de Piridoxal/análise , Ratos , Compostos de Sulfidrila/análise , TemperaturaRESUMO
The steadily increasing number of explosive threat classes, including home-made explosives (HMEs), liquids, amorphous and gels (LAGs), is forcing up the false-alarm rates of security screening equipment. This development can best be countered by increasing the number of features available for classification. X-ray diffraction intrinsically offers multiple features for both solid and LAGs explosive detection, and is thus becoming increasingly important for false-alarm and cost reduction in both carry-on and checked baggage security screening. Following a brief introduction to X-ray diffraction imaging (XDI), which synthesizes in a single modality the image-forming and material-analysis capabilities of X-rays, the Multiple Inverse Fan Beam (MIFB) XDI topology is described. Physical relationships obtaining in such MIFB XDI components as the radiation source, collimators and room-temperature detectors are presented with experimental performances that have been achieved. Representative X-ray diffraction profiles of threat substances measured with a laboratory MIFB XDI system are displayed. The performance of Next-Generation (MIFB) XDI relative to that of the 2nd Generation XRD 3500TM screener (Morpho Detection Germany GmbH) is assessed. The potential of MIFB XDI, both for reducing the exorbitant cost of false alarms in hold baggage screening (HBS), as well as for combining "in situ" liquid and solid explosive detection in carry-on luggage screening is outlined.
RESUMO
Electron microscopic studies of uterine leiomyosarcoma disclose a wide range of differentiation in the neoplastic cells. According to the cytoplasmic appearance undifferentiated, myoblastic, and fibroblast-like cells can be distinguished. Derivation of these cells from mesenchymal cells or poorly developed smooth muscle cells of the myometrium is suggested by the finding of numerous variously differentiated intermediate cell types. The cytoplasm of more differentiated tumour cells usually contains myofilament bundles. Three types of filaments are detected: small, intermediate and thick ones. While the thin ones probably are actin filaments, the intermediate and thick filaments are suggested to represent nonspecific filaments described in a variety of other cell types. Fibroblastic cell types are more often encountered and are usually better differentiated in the premenopausal woman. The possible role of endogenous hormonal factors on the differentiation process of tumour cells is discussed.
Assuntos
Leiomiossarcoma/patologia , Neoplasias Uterinas/patologia , Fatores Etários , Diferenciação Celular , Retículo Endoplasmático/ultraestrutura , Feminino , Fibroblastos/ultraestrutura , Complexo de Golgi/ultraestrutura , Menopausa , Microscopia Eletrônica , Mitose , Músculo Liso/ultraestrutura , Miofibrilas/ultraestrutura , Organoides/ultraestruturaRESUMO
l-Arginase from rat kidney was partially purified and some properties were compared with those of l-arginase of rat liver. The kidney enzyme was firmly bound to the mitochondrial fraction and after solubilization required arginine or an unknown factor in tissue extracts for stabilization after dialysis. The two enzymes differed also in stability with respect to acetone treatment, heating or freezing. In further contrast with liver arginase, arginase from kidney was not adsorbed to CM-cellulose at pH7.5 and its activity was not increased by incubation with Mn(2+). Other differences were seen in relative specificities for substrates, ratio of hydrolysis rates with high and low concentrations of arginine and effects of certain inhibitors. Antisera prepared to pure liver arginase did not cross-react with partially purified kidney arginase.
Assuntos
Arginase , Rim/enzimologia , Acetona , Sulfato de Amônio , Animais , Arginase/antagonistas & inibidores , Arginase/isolamento & purificação , Arginina , Cromatografia DEAE-Celulose , Diálise , Congelamento , Temperatura Alta , Concentração de Íons de Hidrogênio , Hidrólise , Soros Imunes , Fígado/enzimologia , Lisina , Manganês , Mitocôndrias , Ornitina , Ratos , Frações SubcelularesRESUMO
Transcutaneous lower blepharoplasty as a standard procedure for cosmetic lower blepharoplasty is being replaced by transconjunctival blepharoplasty and laser resurfacing techniques. Nevertheless, there remain specific indications for the transcutaneous approach and its modifications. The accomplished facial plastic surgeon will be able to choose the appropriate technique based on the patient's concerns, the eyelid pathology, and his or her clinical experience.
Assuntos
Pálpebras/cirurgia , Cirurgia Plástica/efeitos adversos , Cirurgia Plástica/métodos , Idoso , Feminino , Humanos , Lipectomia/métodos , Masculino , Complicações Pós-Operatórias , Rejuvenescimento , Envelhecimento da PeleRESUMO
Otoplasty has undergone a number of important developments over the course of the past 150 years. While cartilage-incision techniques were favored earlier in the century, suture-only techniques are now favored. Prominauris, a condition that affects 5% of the Caucasian population, is inherited as an autosomal dominant trait. Protruding ears commonly are due to a combination of two defects: under-development of antihelical folding, and overdevelopment of the conchal wall. Utilizing a graduated approach, consistently superior results can be obtained. Our approach includes: fusiform skin excision; concha-mastoid sutures; scapha-conchal sutures; and refinement of the scapha, helix, and lobe. The aesthetic results are well retained and significant complications are rare.
Assuntos
Deformidades Adquiridas da Orelha/etiologia , Orelha Externa/anormalidades , Orelha Externa/cirurgia , Cirurgia Plástica/métodos , Cicatriz/etiologia , Estética , História do Século XIX , História do Século XX , Humanos , Cirurgia Plástica/efeitos adversos , Cirurgia Plástica/história , Infecção da Ferida CirúrgicaRESUMO
Radioimmunologic assay techniques are superior to most analytical procedures with regard to sensitivity, precision, general applicability, and experimental simplicity. Both for diagnosis and for monitoring of therapy this method has greatly advanced our understanding of endocrine physiology. Besides its use in clinical chemistry, radioimmunoassay is also employed in pharmacology, toxicology, and in pharmacokinetics of new drugs.
Assuntos
Radioimunoensaio , Complexo Antígeno-Anticorpo , Sítios de Ligação de Anticorpos , Ligação Competitiva , Feminino , Humanos , Técnicas Imunológicas/métodos , Marcação por Isótopo , Monitorização Fisiológica , Insuficiência Placentária/diagnóstico , Gravidez , Glândula Tireoide/metabolismoRESUMO
Human lung fibroblasts (WI-38) in late exponential phase of growth, in stationary phase after confluency was reached, and at high or low number of population doublings were used to investigate the synthesis of proline and hydroxyproline from glutamate or arginine. Glutamate was from two to five times as effective a precursor as arginine; glutamine did not seem to be involved in these metabolic pathways. Accumulation of protein-bound hydroxyproline in cell layers was observed only after confluency. Confluent cells synthesized more proline from glutamate than did cells in late exponential growth. Conversion of glutamate into intracellular free proline was conducted also to a greater extent in confluent cells at a high number of population doublings. Conversion of glutamate into proline or hydroxyproline in cell-layer protein was not affected significantly by the number of population doublings. Less total protein as well as less hydroxyproline accumulated with cells at a high number of population doublings.
Assuntos
Hidroxiprolina/biossíntese , Prolina/biossíntese , Arginina/metabolismo , Proteínas de Transporte/metabolismo , Contagem de Células , Divisão Celular , Glutamatos/metabolismoRESUMO
The nature of type IV collagen antigens in the serum of streptozotocin diabetic rats was studied using radioimmunoassays for the N-terminal (7S-collagen) and C-terminal domain of type IV collagen. Type IV collagen antigen crossreacting with antibodies to the C-terminal domain was elevated from 32.0 +/- 5.36 ng/ml (n = 10) in serum of normal rats to 94.9 +/- 24.5 ng/ml (n = 10, P less than 0.0001) in serum of streptozotocin diabetic rats and could be normalized to 40.1 +/- 8.30 ng/ml (n = 18) by insulin treatment. Molecular sieve chromatography of serum demonstrated a high molecular weight fraction containing the C-terminal and N-terminal domains and smaller material containing only the N-terminal domain. Degradation of the high molecular weight material by collagenase indicates that it consists of intact collagen type IV. Its relative proportion increased from 42% to 54% 4 weeks after diabetes induction. Together with unaltered clearance rates of 7S collagen in normal and diabetic rats, the data suggest that the increase of collagen type IV antigens in diabetic states reflects increased synthesis of collagen type IV.
Assuntos
Membrana Basal/metabolismo , Colágeno/biossíntese , Diabetes Mellitus Experimental/metabolismo , Animais , Antígenos/análise , Colágeno/sangue , Meia-Vida , Cinética , Masculino , Radioimunoensaio , Ratos , Ratos Endogâmicos , Fatores de TempoRESUMO
1. Homogenates of liver or kidney from rat, mouse, dog and guinea pig formed ornithine from proline but not from glutamate. Rat kidney was most active in this reaction and was used for further studies. 2. The overall reaction was found to be catalysed by proline oxidase to yield glutamic gamma-semialdehyde, followed by transamination of this product with glutamate as catalysed by ornithine-keto acid aminotransferase. 3. The unfavourable equilibrium of the ornithine-keto acid aminotransferase reaction was overcome chiefly by glutamate dehydrogenase in the tissue, which removed the alpha-oxoglutarate produced, by reduction with endogenous ammonia and NADH. 4. Aspartate aminotransferase in these preparations also aided in the removal of alpha-oxoglutarate. In this case the overall reaction was driven also by the rapid decarboxylation of oxaloacetate. 5. No evidence could be found for a pathway of ornithine synthesis involving acylated intermediates as has been observed in some micro-organisms. 6. The rate of ornithine synthesis in homogenates of several rat tissues paralleled the activity of ornithine-keto acid aminotransferase in these tissues, indicating that this enzyme was rate-determining for the synthesis. 7. The possible influence of these reactions on urea synthesis is discussed.
Assuntos
Glutamatos/metabolismo , Rim/metabolismo , Fígado/metabolismo , Ornitina/biossíntese , Prolina/metabolismo , Alanina Transaminase/análise , Animais , Aspartato Aminotransferases/análise , Ácido Aspártico/metabolismo , Isótopos de Carbono , Cães , Eletroforese , Cobaias , Técnicas In Vitro , Cinética , Camundongos , Ratos , EspectrofotometriaRESUMO
In this sensitive radioimmunoassay for laminin fragment P1 (purified from pepsin extracts of human placenta), monovalent antibody fragments obtained from rabbit antisera against the laminin component are used. The inhibition assay showed a low intra- and interassay variability, and the inhibition curves for various serum samples had parallel slopes. Molecular-sieve chromatography demonstrated heterogeneity of the laminin antigen in serum. For quantification we defined arbitrary units based on the amount of antigenic material present in normal human serum. Sera from 361 tumor patients showed increased values in about half of the cases. Correlation with increased concentration of carcinoembryonic antigen was poor (r = 0.259). The assay may be useful for diseases involving basement-membrane metabolism.
Assuntos
Laminina/sangue , Neoplasias/sangue , Membrana Basal/análise , Antígeno Carcinoembrionário/análise , Cromatografia em Gel , Humanos , Fragmentos Fab das Imunoglobulinas/análise , Pepsina A/metabolismo , Fragmentos de Peptídeos/sangue , RadioimunoensaioRESUMO
A radioimmunoassay (RIA) has been developed for the measurement of 2-[N-[(S)-1-ethoxycarbonyl-3-phenylpropyl]-L-alanyl]-(1S,3S,5S)- 2-azabicyclo[3.3.0]octane-3-carboxylic acid (ramipril, Hoe 498) and its active metabolite (diacid: hydrolysis product of ramipril) in serum or plasma. Antibodies to the diacid were raised in rabbits against a lysine analogue conjugated to bovine serum albumin. A 125I-ramipril-diacid derivative was used as radioligand. Separation of the antibody-bound and free radiolabeled ligand was achieved by employing a polyethylene glycol solution. The RIA is specific for the active metabolite (diacid). Studies on specificity showed less than 0.6% cross-reactivity with intact ramipril or with dioxopiperazine metabolites. The levels for intact ramipril were obtained by prior enzymatic hydrolysis to the diacid. The sensitivity of the assay was 0.1 and 0.5 ng/ml for diacid and ramipril, respectively. Intra- and inter-assay coefficients of variation ranged from 3 to 14% at 1 to 30 ng diacid per ml. A recovery experiment yielded an average of 103%. The assay has been used to investigate the pharmacokinetic profile of both ramipril and its pharmacologically active metabolite.
Assuntos
Inibidores da Enzima Conversora de Angiotensina , Compostos Bicíclicos com Pontes/análise , Hidrocarbonetos Aromáticos com Pontes/análise , Animais , Compostos Bicíclicos com Pontes/metabolismo , Bovinos , Humanos , Hidrólise , Cinética , Coelhos , Radioimunoensaio , RamiprilRESUMO
OBJECTIVE: Vestibular stenosis is an uncommon but debilitating cause of nasal obstruction. The etiology of the stenosis is variable, but iatrogenic causes are by far the most common. A number of techniques have been described for repair of the stenotic segment. We present a surgical technique that employs the concepts of: excision of the stenotic segment, enlargement of the bony pyriform aperture, and placement of a full-thickness skin graft. RESULTS: Our results have been very favourable, and we have documented improvement in nasal obstruction by performing preoperative and postoperative nasal airflow studies on all our patients. CONCLUSIONS: These results suggest that significant improvement in nasal airflow can be obtained in most patients with the use of this technique.
Assuntos
Cavidade Nasal/cirurgia , Obstrução Nasal/cirurgia , Deformidades Adquiridas Nasais/cirurgia , Resistência das Vias Respiratórias , Constrição Patológica , Humanos , Doença Iatrogênica , Obstrução Nasal/etiologia , Obstrução Nasal/fisiopatologia , Deformidades Adquiridas Nasais/complicações , Deformidades Adquiridas Nasais/fisiopatologia , Rinoplastia , Transplante de Pele , Retalhos CirúrgicosRESUMO
This paper describes a specific radioimmunological method for determining the diuretic agent piretanide (4 phenoxy-3-(1-pyrrolidinyl)-5-sulfamoyl benzoic acid) in human serum, plasma and urine. The antiserum was raised in rabbits against an immunogen of piretanide coupled to bovine serum albumin. The iodinated hydroxy derivative of piretanide was used as tracer. The separation of free and antibody-bound piretanide was performed by precipitating the antibody-tracer complex by polyethylene glycol. The limit of detection was 4 ng/ml. Studies on specificity showed less than 0.5% cross-reactivity of an identified metabolite. Interassay reproducibility showed an average coefficient of variation of 7.3%, the interassay variation was 5%. A recovery experiment yielded 100.9% recovery. There is good agreement between parallel determinations of piretanide by RIA and HPLC in both human serum and urine.