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PubMed1999

Mental distress--gender aspects of symptoms and coping.

The article examines men's and women's views on their reasons for mental distress and on their coping styles, respectively. The data were taken from written statements given on two open-ended questions from a survey questionnaire returned by 43 men and 57 women who were self-reported, long-term users of these drugs, and from taped interviews with 10 respondents. Men's accounts (n = 25) expressed a layered theory of mental health: alcohol was a remedy to alleviate temporary strain caused by external pressure, while the use of psychotropic drugs indicated a loss of a men's assumed self-regulatory powers and autonomy. Women's accounts (n = 31) were stories of emotional pain related to their caring work in the private sphere, and psychotropics restored their capacity to carry out emotional labor.

Adaptation, Psychological↗
PubMed1988

Induced population growth and induced technological progress: their interaction in the accelerating stage.

"A simple model of Malthusian population growth combined with population-induced technological progress generates accelerating growth. The model may be relevant for a first stage of growth in which natural resource limitations can be overcome through technological progress; it is not applicable to a later stage in which resource constraints are more resistant. Parameter values are roughly inferred from historical experience." (SUMMARY IN FRE)

Conservation of Natural Resources↗
PubMed2001

Influence of the activation temperature on the SO2 removal capacity and mechanical performance of pelletized activated chars.

The influence of steam activation temperature on the SO2 removal capability of subbituminous coal char pellets (SCCP) as well as the changes in their mechanical properties, were studied. The SCCP were prepared by pressing at 125 MPa a blend of a char, obtained by carbonization at 850 degrees C, and a commercial coal tar pitch. After a curing stage in air at 200 degrees C and a heat treatment at 900 degrees C in nitrogen, the SCCP were activated with steam (10g H2O min(-1)) for two hours at several temperatures: 600, 700, 750 and 800 degrees C. The SO2 adsorption capacity tests carried out at simulated flue gas conditions (100 degrees C, 10% H2O, 6% O2, 1s space velocity) show an important increase in the amount of adsorbed SO2 of the activated SCCP with respect to parent ones, whereas their mechanical performance decreases in the same proportion, mainly in the interval 700-750 degrees C. Increasing the temperature of activation, the SCCP undergo significant changes in textural features (total surface area measured in N2 and CO2, pore volume) as well as in surface oxygenated groups, as shown by TPD experiments. There is an optimum ratio between both parameters (around 8 micromol g(-1)) for the SO2 conversion at the studied conditions.

Adsorption↗
PubMed1975

Study of the developmental pattern of heme catabolism in liver and the effects of cobalt on cytochrome P-450 and the rate of heme oxidation during the neonatal period.

The comparative development patterns of heme oxidation andof cytochrome P-450 dependent drug oxidation in rat liver were examined. High levels of heme oxygenase activity were present in whole embryo preparations at day 13 of gestation. At birth this enzyme activity in liver was approximately equal to that of normal adult liver. In the immediate postnatal period the rate of hepatic heme oxidation increased sharply, reaching levels 3-5 times normal during the first week postpartum. Thereafter, this enzyme activity progressively decreased and returned to normal adult levels by the 28th postpartum day. The development of microsomal heme oxidation and of P-450 dependent drug oxidation exhibited reciprocal patterns, with the latter being at low levels of activity during the immediate postnatal period and reaching adult activity only 4 or more wk after birth. Cobalt injected into pregnant animals or in to nursing mothers did not induce heme oxygenase in the fetus or suckling neonate. However, when treated directly with the metal, 4-day old neonates exhibited a small induction response of this enzyme; and the inducibility of heme oxygenase increased gradually to fully adult levels by the end of the 4th postpartum week. Cobalt at all postnatal developmental stages was capable of diminishing hepatic contents of total microsomal heme and P-450; however this effect of the metal was small in the immediate period after birth and increased progressively with maturation. These findings demonstrate that the patterns of development of hepatic capacity for carrying out the oxidation of heme and the P-450 dependent oxidation of drugs are different and thus provide further evidence that these microsomal enzyme systems are distinct from each other and under separate regulatory mechanisms. The degree of induction response for hepatic heme oxygenase evoked by the trace metal, cobalt, was also shown to have developmental determinants as did the susceptibility of hepatic cytochrome P-450 to degradation by this metal. The very high levels of hepatic heme oxygenase activity which characterize neonates during the first week of life indicate that over-production of bilirubin contributes significantly to the mechanism of neonatal jaundice.

Animals↗
PubMed1991

Target detection and movement discrimination in the blind field of hemispherectomized patients.

Four hemispherectomized patients were tested with a variety of tasks designed to investigate the extent of residual vision in the blind field. The first set of studies was aimed at evaluating the ability of these subjects to detect and localize at various eccentricities three types of targets which differed in their spatiotemporal properties (stationary, flashing and moving). The subjects could detect effectively the presence of any of these stimuli in their blind field and they experienced little difficulty in discerning blank from target trials. When manual pointing was used to measure localization quality, the hemianopes made more errors in their blind field but their accuracy, when detection was correct, was comparable with that observed in their intact visual field and in that of the control subjects. In the second set of experiments, the capacity of 3 of the subjects to detect in their blind field a moving grating, as well as to discriminate between relative grating velocities and directions in their blind field and in both fields simultaneously, was assessed. Two subjects could detect the movement in their blind field, although this was in part affected by stimulus velocity. When discrimination of relative velocities in the blind field and in both fields simultaneously was evaluated, individual differences were observed. However, all subjects showed some capacity to carry out the task. Finally, none of the experimental subjects was able to discriminate the relative directions of the moving gratings. The results are discussed in terms of collicular involvement to account for the residual vision observed in the blind field of hemispherectomized subjects.

Brain↗
PubMedDate not supplied

Selective primary health care: strategies for control of disease in the developing world. XV. Acute diarrhea.

Diarrhea claims the lives of at least five million children per year and is a major contributor to malnutrition in developing countries. A variety of infectious agents cause diarrhea through several pathogenic mechanisms. Bacteria such as Shigella can directly invade the intestinal mucosa, and those similar to Vibrio cholerae or enterotoxigenic Escherichia coli can produce toxins that alter cellular absorption and secretions. Rotavirus appears to cause 30%-40% of diarrhea in toddlers. Diarrhea frequently accompanies parasitic infestation and infections in other parts of the body. Several methods, including improvement of water supplies and sanitation and administration of vaccines and antibiotics, may be useful in preventing mortality and morbidity due to diarrhea. Oral rehydration to replace fluids and electrolytes, accompanied by attention to early feeding and encouragement of breast feeding, is the most effective and economical intervention currently available.

Acute Disease↗
PubMed1987

Value for money in the health sector: the contribution of primary health care.

Since the Alma-Ata Declaration in 1978, primary health care (PHC) has been seen in most countries as a vital part of any strategy to improve the health of the population. Economic evaluations of PHC delivery and PHC activities are therefore needed to assist in decision-making on resource use in the health sector. A report was prepared on such economic evaluations in the Commonwealth and this paper summarizes those findings which relate to developing Commonwealth countries. After a brief explanation of the main methods of economic evaluation, existing evaluations, classified according to the eight essential elements of PHC, are reviewed. The literature review throws up a number of methodological issues of which policy-makers need to be aware when interpreting evaluations. These are pointed out before moving on to a consideration of what lessons the literature may hold about the value and affordability of PHC and the most efficient ways of delivering PHC activities. The final section suggests that, although economic evaluation techniques have an important role to play in decision-making, they have not so far been used to best advantage. A number of ways in which health ministries could increase the usefulness of the evaluations they commission are considered.

Cost-Benefit Analysis↗
PubMed2001

Identification of the yeast cytidine deaminase CDD1 as an orphan C-->U RNA editase.

Yeast co-expressing rat APOBEC-1 and a fragment of human apolipoprotein B (apoB) mRNA assembled functional editosomes and deaminated C6666 to U in a mooring sequence-dependent fashion. The occurrence of APOBEC-1-complementing proteins suggested a naturally occurring mRNA editing mechanism in yeast. Previously, a hidden Markov model identified seven yeast genes encoding proteins possessing putative zinc-dependent deaminase motifs. Here, only CDD1, a cytidine deaminase, is shown to have the capacity to carry out C-->U editing on a reporter mRNA. This is only the second report of a cytidine deaminase that can use mRNA as a substrate. CDD1-dependent editing was growth phase regulated and demonstrated mooring sequence-dependent editing activity. Candidate yeast mRNA substrates were identified based on their homology with the mooring sequence-containing tripartite motif at the editing site of apoB mRNA and their ability to be edited by ectopically expressed APOBEC-1. Naturally occurring yeast mRNAs edited to a significant extent by CDD1 were, however, not detected. We propose that CDD1 be designated an orphan C-->U editase until its native RNA substrate, if any, can be identified and that it be added to the CDAR (cytidine deaminase acting on RNA) family of editing enzymes.

APOBEC-1 Deaminase↗
PubMed2003

Enzymes of jasmonate biosynthesis occur in tomato sieve elements.

The allene oxide cyclase (AOC) is a plastid-located enzyme in the biosynthesis of the signaling compound jasmonic acid (JA). In tomato, AOC occurs specifically in ovules and vascular bundles [Hause et al. (2000) Plant J. 24; 113]. Immunocytological analysis of longitudinal sections of petioles and flower stalks revealed the occurrence of AOC in companion cells (CC) and sieve elements (SE). Electron microscopic analysis led to the conclusion that the AOC-containing structures of SE are plastids. AOC was not detected in SE of 35S::AOCantisense plants. The enzymes preceding AOC in JA biosynthesis, the allene oxide synthase (AOS) and the lipoxygenase, were also detected in SE. In situ hybridization showed that the SE are free of AOC-mRNA suggesting AOC protein traffic from CC to SE via plasmodesmata. A control by in situ hybridization of AOS mRNA coding for a protein with a size above the exclusion limit of plasmodesmata indicated mRNA in CC and SE. The data suggest that SE carry the capacity to form 12-oxo-phytodienoic acid, the unique precursor of JA. Together with preferential generation of JA in vascular bundles [Stenzel et al. (2003) Plant J. 33: 577], the data support a role of JA in systemic wound signaling.

Cyclopentanes↗