RESUMO
The antineutrino spectra measured in recent experiments at reactors are inconsistent with calculations based on the conversion of integral beta spectra recorded at the ILL reactor. (92)Rb makes the dominant contribution to the reactor antineutrino spectrum in the 5-8 MeV range but its decay properties are in question. We have studied (92)Rb decay with total absorption spectroscopy. Previously unobserved beta feeding was seen in the 4.5-5.5 region and the GS to GS feeding was found to be 87.5(25)%. The impact on the reactor antineutrino spectra calculated with the summation method is shown and discussed.
RESUMO
The ß feeding probability of (102,104,105,106,107)Tc, 105Mo, and 101Nb nuclei, which are important contributors to the decay heat in nuclear reactors, has been measured using the total absorption technique. We have coupled for the first time a total absorption spectrometer to a Penning trap in order to obtain sources of very high isobaric purity. Our results solve a significant part of a long-standing discrepancy in the γ component of the decay heat for 239Pu in the 4-3000 s range.
Assuntos
Domínio Catalítico , Proteínas de Choque Térmico/química , Isomerases/química , Ressonância Magnética Nuclear Biomolecular , Estrutura Secundária de Proteína , Radioisótopos de Carbono/química , Humanos , Isoenzimas/química , Radioisótopos de Nitrogênio/química , Isomerases de Dissulfetos de Proteínas , PrótonsRESUMO
Protein-disulfide isomerase (PDI) is a catalyst of folding of disulfide-bonded proteins and also a multifunctional polypeptide that acts as the beta-subunit in the prolyl 4-hydroxylase alpha(2)beta(2)-tetramer (P4H) and the microsomal triglyceride transfer protein alphabeta-dimer. The principal peptide-binding site of PDI is located in the b' domain, but all domains contribute to the binding of misfolded proteins. Mutations in the C-terminal part of the a' domain have significant effects on the assembly of the P4H tetramer and other functions of PDI. In this study we have addressed the question of whether these mutations in the C-terminal part of the a' domain, which affect P4H assembly, also affect peptide binding to PDI. We observed a strong correlation between P4H assembly competence and peptide binding; mutants of PDI that failed to form a functional P4H tetramer were also inactive in peptide binding. However, there was also a correlation between inactivity in these assays and indicators of conformational disruption, such as protease sensitivity. Peptide binding activity could be restored in inactive, protease-sensitive mutants by selective proteolytic removal of the mutated a' domain. Hence we propose that structural changes in the a' domain indirectly affect peptide binding to the b' domain.
Assuntos
Isomerases de Dissulfetos de Proteínas/química , Sequência de Aminoácidos , Sequência de Bases , Humanos , Dados de Sequência Molecular , Mutação , Peptídeos/química , Ligação Proteica/genética , Conformação Proteica , Isomerases de Dissulfetos de Proteínas/genéticaAssuntos
Isomerases de Dissulfetos de Proteínas/química , Sequência de Aminoácidos , Isótopos de Carbono , Clonagem Molecular , Hidrogênio , Isótopos de Nitrogênio , Ressonância Magnética Nuclear Biomolecular/métodos , Fragmentos de Peptídeos/química , Conformação Proteica , Dobramento de Proteína , Estrutura Secundária de Proteína , Proteínas Recombinantes/químicaRESUMO
Protein disulfide isomerase (PDI) is a multifunctional polypeptide that acts as a subunit in the animal prolyl 4-hydroxylases and the microsomal triglyceride transfer protein, and as a chaperone that binds various peptides and assists their folding. We report here that deletion of PDI sequences corresponding to the entire C-terminal domain c, previously thought to be critical for chaperone activity, had no inhibitory effect on the assembly of recombinant prolyl 4-hydroxylase in insect cells or on the in vitro chaperone activity or disulfide isomerase activity of purified PDI. However, partially overlapping critical regions for all these functions were identified at the C-terminal end of the preceding thioredoxin-like domain a'. Point mutations introduced into this region identified several residues as critical for prolyl 4-hydroxylase assembly. Circular dichroism spectra of three mutants suggested that two of these mutations may have caused only local alterations, whereas one of them may have led to more extensive structural changes. The critical region identified here corresponds to the C-terminal alpha helix of domain a', but this is not the only critical region for any of these functions.
Assuntos
Isomerases de Dissulfetos de Proteínas/química , Isomerases de Dissulfetos de Proteínas/metabolismo , Sequência de Aminoácidos , Animais , Caenorhabditis elegans/enzimologia , Caenorhabditis elegans/genética , Domínio Catalítico/genética , Dicroísmo Circular , Dimerização , Escherichia coli/genética , Humanos , Técnicas In Vitro , Chaperonas Moleculares/química , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Dados de Sequência Molecular , Nucleopoliedrovírus/genética , Mutação Puntual , Conformação Proteica , Isomerases de Dissulfetos de Proteínas/genética , Estrutura Secundária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Deleção de Sequência , SpodopteraRESUMO
ERp60 (also known as ERp61 or GRP58) is an isoform of protein disulfide isomerase (PDI) that has two thioredoxin-like domains a and a' in positions corresponding to those of domains a and a' in the PDI polypeptide and shows a significant amino acid sequence similarity to PDI in almost all parts. We report here that the human ERp60 gene is about 18 kb in size and consists of 13 exons. No distinct correlation was found between its exon-intron organization and the modular structure of the ERp60 polypeptide, nor were any similarities in exon-intron organization found between the human ERp60, PDI, and thioredoxin genes. The 5' flanking region of the ERp60 gene has no TATAA box or CCAAT motif but contains several potential binding sites for transcription factors. The highest levels of expression of the ERp60 mRNA were found by Northern blotting in the liver, placenta, lung, pancreas, and kidney, and the lowest in the heart, skeletal muscle, and brain. We also isolated an intronless ERp60 gene that probably represents a pseudogene. The ERp60 gene was mapped by fluorescence in situ hybridization to 15q15 and the processed gene to 1q21, so that neither was located on the same chromosome as the human PDI and thioredoxin genes.
Assuntos
Cromossomos Humanos Par 15 , Cromossomos Humanos Par 1 , Proteínas de Choque Térmico/genética , Isomerases/genética , Pseudogenes , Tiorredoxinas/genética , Sequência de Aminoácidos , Sequência de Bases , Mapeamento Cromossômico , Clonagem Molecular , DNA , Éxons , Expressão Gênica , Proteínas de Choque Térmico/química , Humanos , Íntrons , Isomerases/química , Dados de Sequência Molecular , Peptídeos/química , Peptídeos/genética , Isomerases de Dissulfetos de ProteínasRESUMO
We have examined patterns of variation of several kinds of molecular markers (isozymes, RFLPs of ribosomal DNA and anonymous low-copy number DNA, RAPDs and microsatellites) and an adaptive trait [date of bud set in Scots pine (Pinus sylvestris L.)]. The study included Finnish Scots pine populations (from latitude 60°N to 70°N) which experience a steep climatic gradient. Common garden experiments show that these populations are adapted to the location of their origin and genetically differentiated in adaptive quantitative traits, e.g. the date of bud set in first-year seedlings. In the northernmost population, bud set took place about 21 days earlier than in the southernmost population. Of the total variation in bud set, 36.4% was found among the populations. All molecular markers showed high levels of within-population variation, while differentiation among populations was low. Among all the studied markers, microsatellites were the most variable (He=0.77). Differences between populations were small, GST was less than 0.02. Our study suggests that molecular markers may be poor predictors of the population differentiation of quantitative traits in Scots pine, as exemplified here by bud-set date.
Assuntos
Pesquisa , Redação , Autoria , Humanos , Editoração , Garantia da Qualidade dos Cuidados de SaúdeRESUMO
The structure and variation of nuclear ribosomal DNA (rDNA) units of Picea abies, (L.) Karst. was studied by restriction mapping and Southern hybridization. Conspicuous length variation was found in the internal transcribed spacer (ITS) region of P. abies, although the length of this region is highly conserved both within and among most of the plant species. Two types of ITS variants (A and B), displaying a size difference of 0.5 kb in the ITS2 region, were present within individuals of P. abies from Sweden, Central Europe and Siberia. A preliminary survey of 14 additional Eurasian and North American species of Picea suggested that length variation in the ITS region is widespread in this genus. Alltogether three length variants (A, B and C) were identified. Within individuals of eight Picea species, two length variants were present within the genome (combinations of A and B variants in P. glehnii, P. maximowiczii, P. omorika, P. polita and P. sitchensis and variants B and C in P. jezoensis, P. likiangensis and P. spinulosa). Within individuals from five species, however only one rDNA variant was present in their genome (variant A in P. aurantiaca, P. engelmannii, P. glauca, P. koraiensis and P. koyamai; variant B in P. bicolor). The ITS length variation will be useful as a molecular marker in evolutionary studies of the Picea species complex, whose phylogeny is controversial. The presence of intraindividual variation in, and shared polymorphism of the, ITS length variants raises questions about the occurrence of interspecific hybridization during the evolutionary history of Picea.
RESUMO
Pivampicillin and doxycycline were compared in the treatment of chlamydial urethritis in 80 heterosexual men. The trial was carried out in a double-blind, comparative parallel group fashion. Forty patients were treated with 700 mg of pivampicillin twice daily and another 40 with 200 mg of doxycycline on the first day and thereafter with 100 mg of doxycycline and one placebo tablet daily. Both treatments lasted for 9 days. Follow-up examinations were carried out 2 weeks (14-16 days) and 4 weeks (26-30 days) after the start of treatment. Altogether five (12.5%) of the forty pivampicillin-treated patients were clinical failures and three (7.5%) still harbored Chlamydia trachomatis after treatment. The corresponding figures for the doxycycline-treated patients were two (5.1%) and one (2.6%). The difference between the treatment results of the two groups did not reach statistical significance.
Assuntos
Ampicilina/análogos & derivados , Infecções por Chlamydia/tratamento farmacológico , Doxiciclina/uso terapêutico , Pivampicilina/uso terapêutico , Uretrite/tratamento farmacológico , Método Duplo-Cego , Humanos , Masculino , Projetos de PesquisaRESUMO
Screening of red-green colour vision defects was done for 52 school children (22 boys and 30 girls) and 231 trade school students (226 boys and 5 girls) with three different kinds of pseudo-isochromatic plates: Ishihara (1983), Boström-Kugelberg (1972), and Standard Pseudoisochromatic Plates part 1 (SPP 1) 1978, and with three different kinds of vision screeners: Keystone View Model DVS 2, Bausch and Lomb Vision Tester, and Rodenstock Farbentestscheibe 3040.173. After these tests, each subject was examined with the Nagel Anomaloscope; this revealed 26 red-green defectives in the study group. Ishihara found 20/26 (76.9%), Boström-Kugelberg 24/26 (92.3%), and SPP 1 17/26 (65.4%) of the defectives. None of the normals were diagnosed as defectives with Ishihara or SPP 1. With Boström-Kugelberg four normals were diagnosed as defectives. Keystone found 24/26 (92.3%), Bausch and Lomb 26/26 (100%), and Rodenstock 25/26 (96.2%) of the defectives. But 9, 21, and 112 normals, respectively, were diagnosed as defective. In the present study, the Boström-Kugelberg and Ishihara plates as well as Keystone Vision Screener and Bausch and Lomb Vision tester came close to an effective screening test and could be recommended for screening red-green colour vision defects in occupational health care.
Assuntos
Percepção de Cores , Defeitos da Visão Cromática/diagnóstico , Testes Visuais/métodos , Adolescente , Adulto , Criança , Feminino , Humanos , MasculinoRESUMO
Segmental epidural analgesia (T10-T12) was performed in 418 parturients, using a 4-6 ml dose of 0.5% bupivacaine, with or without adrenaline. Seventy per cent of parturients were primiparas and 30% had histories, or signs, of possible uteroplacental insufficiency. Our aim was to relieve pain during the long passive opening phase, so that mothers would be rested and active at the beginning of the second phase, but also to avoid abolishing the bearing-down reflex, the absence of which causes an increased frequency of instrumental delivery. The analgesia during the opening phase was of good quality in 89% of primiparas, and 84% of multiparas. The onset of analgesia was rapid (3-5 min) and the duration was on average 2 1/2 h. The incidence of foetal heart rate changes, during the 30 min after epidural, was 5%. The second phase was less than 30 min in about 90% of cases. About 90% of parturients delivered spontaneously, and the frequency of instrument delivery was only 7.4%. Caesarean section was required in 3.7%. Slight, but rapidly correctable, hypotension occurred in 16.5%, and in two cases the hypotension led to more serious complications. This stresses the importance of the availability and competence of both the anaesthetic and obstetric teams. There were no maternal or neonatal mortalities, and the Apgar scores compared well with the figures for the normal material in our obstetric unit.
Assuntos
Anestesia Epidural/métodos , Anestesia Obstétrica/métodos , Bupivacaína , Índice de Apgar , Bupivacaína/administração & dosagem , Bupivacaína/efeitos adversos , Feminino , Coração Fetal/efeitos dos fármacos , Humanos , Hipotensão/induzido quimicamente , Primeira Fase do Trabalho de Parto/efeitos dos fármacos , Segunda Fase do Trabalho de Parto/efeitos dos fármacos , Paridade , Gravidez , Contração Uterina/efeitos dos fármacosRESUMO
Arterial and venous blood lidocaine concentrations were intermittently measured in 15 bronchoscopy patients in whom local anaesthesia was induced by an inhalation technique. A DeVillbiss ultrasonic nebulizer model 3574 was used. The anaesthetic was 10 ml of 4% lidocaine without adrenaline. Blood concentrations were measured 5 min after commencement of inhalation, on completion of inhalation, and then after 10, 30 and 60 min. Statistically significantly higher concentrations were found in the arterial blood at the first two sampling times (P less than 0.01 and P less than 0.05, respectively). The highest average concentration in both arterial and venous blood eas reached 10 min after completion of anaesthesia. After 30 min, there was no difference between the arterial and venous samples; and after 60 min, the concentration was higher in venous blood. The highest individual concentration was 2.8 mug/ml in arterial blood and 2.1 mug/ml in venous blood, well below that reported to cause systemic toxic symptoms. Thus, the inhalation technique may be considered a safe means of inducing anaesthesia in the respiratory tract.
Assuntos
Anestesia Local/métodos , Broncoscopia , Lidocaína/administração & dosagem , Adulto , Anestesia Local/instrumentação , Humanos , Lidocaína/sangue , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , UltrassomRESUMO
Thiopentone and Althesin were compared in 50 patients undergoing general anaesthesia for Caesarean section. The patients were divided into group A (24 mothers) were thiopentone (3.5 mg/kg) was used for induction and group B (26 mothers) where Althesin (80 mu1/kg) was employed. Blood samples for estimating the maternal and umbilical venous and arterial blood pH, pCO2, BD and pO2 were taken at the time of delivery. The clinical condition of the newborn were estimated by the Apgar score. Postoperatively the mothers were interviewed about thei subjective opinion concerning the anaesthesia. The interview showed equal acceptance of both induction agents. The umbilical venous and arterial pH, pCO2 and BD were well within the normal physiological range and there was no significant intergroup difference. The only significant differences were the lower umbilical venous and arterial pO2 values in the Althesin group. The clinical condition of the newborn (Apgar score) showed no significant difference between the two groups.
Assuntos
Mistura de Alfaxalona Alfadolona , Anestesia Geral , Anestesia Obstétrica , Cesárea , Pregnanodionas , Tiopental , Índice de Apgar , Dióxido de Carbono/sangue , Depressão Química , Feminino , Sangue Fetal/análise , Humanos , Concentração de Íons de Hidrogênio , Recém-Nascido , Oxigênio/sangue , GravidezRESUMO
We describe a method for determination of pregnenolone, progesterone, 17alpha-hydroxyprogesterone, testosterone, and 5alpha-dihydrotestosterone in 1-2 ml of serum from male or female. Using microcolumns of Lipidex-5000 (hydroxyalkoxypropyl Sephadex, 0.5 g) and light petroleum/chloroform (97/3) as the solvent during chromatography, we resolved these five steroids into four fractions, with pregnenolone and 5alpha-dihydrotestosterone eluting together. By use of selected antibodies, the latter two steroids were also determined specifically. Use of microcolumns allowed minimization of solvent volumes and sample transfers. Consequently, blank values for all the five steroids were negligible. Lowest measureable concentrations (in ng/liter) were: pregnenolone 100, progesterone 25, 17alpha-hydroxyprogesterone 50, testosterone 25, and 5alpha-dihydrotestosterone 25. Intra-assay and inter-assay coefficients of variation ranged from 5 to 9% and 10 to 15%, respectively, for the five steroids. Serum concentrations of these steroids are given for women in the follicular and luteal phases of the menstrual cycle and for women on oral contraceptives of the combination type, as well as for normal men.
Assuntos
Di-Hidrotestosterona/sangue , Progestinas/sangue , Testosterona/sangue , Especificidade de Anticorpos , Cromatografia em Gel , Anticoncepcionais Orais/farmacologia , Feminino , Humanos , Hidroxiprogesteronas/sangue , Masculino , Menstruação , Microquímica , Pregnenolona/sangue , Progesterona/sangue , RadioimunoensaioRESUMO
With the present trend away from the designing of individual buildings and towards the systematic planning of whole residential communities, it should be possible to take mental health requirements into account at the planning stage. At present, sociologists are all too seldom consulted on matters of residential planning. When discussing the relationship between housing and mental health one cannot restrict oneself only to the external aspects of the house, but rather one must also consider the opportunities available for the members of the family to satisfy their own needs, both within the home and in its immediate surroundings. Factors which may affect residential requirements include geographical location, type and standard of dwelling and time and continuity of occupation. A move between two districts or groups representing different housing norms and values may lead to withdrawal symptoms in the individual. This may arise equally well from the remoteness of the country districts as from the conflicting pressures brought on by the abundance of contacts available in the large towns. Town life tends to heighten susceptibility to neuroses and personality conflicts. The character of a residential area may affect the mental health of its occupants. Faris & Dunham (4), in studying the incidence of various types of mental illness with an urban population, observed that schizophrenia was most common among people who were in some way isolated from social involvement. The striving for spaciousness in residential areas and the creation of a "summer city" or "garden city" image or a "family-centred way of life" may lead to unexpected problems and have a variety of social consequences. Mental health difficulties have been noted, for example, among housewives in "dormitory" towns or suburbs (11). The institutions required by a community may be grouped into four categories, representing the basic needs of its members. These are (1) economic institutions, (2) social and political organizations, (3) leisure-time clubs and (4) societies and institutions for promoting social integration, including educational, advisory and assistance bodies. The study of satiation processes offers an interesting approach to the relationship between housing and mental health. Man requires new stimuli to motivate him. Boredom and satiation serve to induce passivity and may provoke destructive behaviour and escapism. Finland has the highest percentage of dwellings constructed in the immediate post-war period of any country in Europe, and in respect of the functions of housing many aspects are still apparent which are detrimental to mental health.
Assuntos
Habitação , Saúde Mental , Humanos , Características de Residência , População Rural , Saciação , Países Escandinavos e Nórdicos , Classe Social , População UrbanaRESUMO
A method of utilizing an ultrasonic nebulizer (De Vilbiss 35 A) in local anesthesia for bronchoscopy is described. 10 ml of 4% Licocaine without adrenaline was used as anesthetic agent. Blood levels of Lidocaine were determined on 12 patients. The maximum blood levels were reached 6-8 min after the end of anesthesia. Blood lelvels ranged from 0.37 to 3.28 mug/ml being so in the nontoxic dosage range. A satisfactory anesthesia was achieved in 95% of the 1,043 patients subjected to bronchoscopy, while 5% felt that laryngeal anesthesia was not complete. In no case was it necessary to use the conventional way to complete the anesthesia. Nebulizer anesthesia was preferred by 100 persons who had been anesthetized by both the conventional method and the ultrasonic technique.