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PubMed2006

[Protection factors against alcohol consumption as perceived by basic education teachers].

This research aims to understand how basic education teachers perceive factors that protect against alcohol consumption. An exploratory qualitative methodological approach is adopted. Semi-structured interviews and non-structured observation techniques are applied to a sample of 25 teachers. Content analysis of data gave rise to three thematic categories: the Meaning of Alcohol/Alcoholism; The School as an Area of Protection against Alcohol Consumption; the Teacher as a Protective Agent. The first one is interpreted as a harmful substance and a sociocultural problem situation. Protection is linked up with informing, communicating, educating or caring. Thus, the way teachers see their function ranges from guide to adviser or protector. Most teachers do not feel prepared for it, on the basis of psychopedagogical deficits, integral health knowledge, the legal framework and, mainly, their own prejudices on alcoholism.

Alcohol Drinking↗
PubMed1989

Disturbances in the balance between aggressive and protective factors in the gastric and duodenal mucosa.

A brief description is made of agents that may damage the gastric and duodenal mucosa, and of the more important protective factors. The main protective mechanisms are the same in the two organs, but their relative contributions are different. Some bacteria are able to live on the gastric mucosa by utilizing mucosal defence mechanisms to protect themselves against acid and pepsin. Some drugs may damage the mucosa by interfering with the protective mechanisms. The non-steroidal anti-inflammatory drugs (NSAIDs) reduce the mucosal synthesis of prostaglandins, which are important protective factors.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1993

Cancer-protective factors in fruits and vegetables: biochemical and biological background.

Cancer-protective factors are present in several fruits, vegetables and commonly used spices and herbs. They can be divided into several different groups, based on their chemical structure, e.g. polyphenols, thiols, carotenoids and retinoids, carbohydrates, trace metals, terpenes, tocopherols and degradation products of glucosinolates (i.e. isothiocyanates, indoles and dithiothiols) and others. Among each of these groups of compounds are substances, which may exert their cancer-protective action by more than one biochemical mechanism. The biochemical processes of carcinogenesis are still not known in detail and probably varies with the cancer disease in question. Accordingly, the description of the biochemical backgrounds for the actions of cancer-protective factors must be based on a simplified model of the process of carcinogenesis. The model used in this presentation is a generalised initiation-promotion-conversion model, in which initiators are thought to be directly or indirectly genotoxic, promoters are visualised as substances capable of inferring a growth advantage on initiated cells and converters are believed to be genotoxic, e.g. mutagens, clastogens, recombinogens or the like. Experimental evidence for the mechanisms of action of cancer-protective agents in fruits and vegetables that protect against initiation include the scavenging effects of polyphenols on activated mutagens and carcinogens, the quenching of singlet oxygen and radicals by carotenoids, the antioxidant effects of many compounds including ascorbic acid and polyphenols, the inhibition of activating enzymes by some flavonols and tannins, the induction of oxidation- and of conjugation (protective) enzymes by indoles, isothiocyanates and dithiothiones, the shielding of sensitive structures by some polyphenols and the stimulation of DNA-repair exerted by sulphur-containing compounds. Mechanisms at the biochemical level in anti-promotion include the antioxidant effects of carotenoids and the membrane stabilizing effects reported with polyphenols, the inhibition of proteases caused by compounds from soybeans, the stimulation of immune responses seen with carotenoids and ascorbic acid and the inhibition of ornithine decarboxylase by polyphenols and carotenoids. A few inhibitors of conversion have been identified experimentally, and it can be argued on a theoretical basis, that many inhibitors of initiation should also be efficient against conversion. The mechanisms of anticarcinogenic substances in fruits and vegetables are discussed in the light of cancer prevention and inhibition.

Animals↗
PubMed2000

Protective factors, resiliency and healthy youth development.

The last decade has been characterized by an increasing focus on the question: "What works to promote and protect the health and well-being of adolescents?" This question is raised in multiple arenas, from pregnancy prevention to substance use and violence prevention, as well as for broad populations of young people. An accumulating body of evidence underscores the effectiveness of a dual strategy of enhancing protective factors and promoting healthy youth development while seeking to reduce risk factors in the lives of youth. Building upon research frameworks of the 1970s and 1980s that emphasized the concepts of resiliency, risk, vulnerability, and protective factors, this research provides insights into best practices when the weight of evidence is sufficiently developed, as well as ideas about "best bets" when strategies show particular promise. Critical to the ongoing advancement of adolescent health is a powerful, evidence-based response to the argument that "nothing can be done" for high-risk youth. This perspective must be superseded by practitioners, researchers, and advocates who demonstrate, at multiple points of intervention, that the dual approach of risk reduction and enhancement of protective factors constitutes an effective strategy for adolescent health promotion.

Adolescent↗
PubMed2003

Sun protection factor determination in vivo using a single exposure on sunscreen-protected skin.

BACKGROUND: Determining sunscreen sun protection factors (SPFs) in a cohort of volunteers, particularly on products designed to provide high levels of protection, can be time-consuming. The conventional approach is to administer to each subject a series of exposures (normally between five and seven) on their sunscreen-protected skin. METHOD: A method, based on Gaussian statistics, is proposed that requires just a single exposure on the sunscreen-protected skin in volunteers to arrive at a reliable estimate of the mean SPF of a test product. RESULTS/CONCLUSION: The method is shown to yield an estimate of a product's mean SPF that is comparable, or better, in accuracy to estimates obtained by conventional multi-exposure testing.

Cohort Studies↗
PubMed1998

Definition of amide protection factors for early kinetic intermediates in protein folding.

Hydrogen-deuterium exchange experiments have been used previously to investigate the structures of well defined states of a given protein. These include the native state, the unfolded state, and any intermediates that can be stably populated at equilibrium. More recently, the hydrogen-deuterium exchange technique has been applied in kinetic labeling experiments to probe the structures of transiently formed intermediates on the kinetic folding pathway of a given protein. From these equilibrium and nonequilibrium studies, protection factors are usually obtained. These protection factors are defined as the ratio of the rate of exchange of a given backbone amide when it is in a fully solvent-exposed state (usually obtained from model peptides) to the rate of exchange of that amide in some state of the protein or in some intermediate on the folding pathway of the protein. This definition is straightforward for the case of equilibrium studies; however, it is less clear-cut for the case of transient kinetic intermediates. To clarify the concept for the case of burst-phase intermediates, we have introduced and mathematically defined two different types of protection factors: one is P struc, which is more related to the structure of the intermediate, and the other is P app, which is more related to the stability of the intermediate. Kinetic hydrogen-deuterium exchange data from disulfide-intact ribonuclease A and from cytochrome c are discussed to explain the use and implications of these two definitions.

Amides↗
PubMed1996

Prenatal and perinatal risk and protective factors for neonatal intracranial hemorrhage. National Institute of Child Health and Human Development Neonatal Research Network.

OBJECTIVE: To identify prenatal and perinatal risk and protective factors for grade III and IV intracranial hemorrhage (ICH) in 4795 singleton infants (weight, < or = 1500 g). METHOD: Prenatal and perinatal risk and protective factors for ICH were examined initially by univariate analysis and adjusted for year of birth, followed by multivariate logistic regression analysis that adjusted simultaneously for the effects of year of birth and prenatal and perinatal characteristics. SETTING: Seven tertiary care neonatal-perinatal centers. RESULTS: By univariate analysis, African-American race, prenatal care, older maternal age, hypertension or preeclampsia, antenatal steroid administration, cesarean section delivery, increasing birth weight, increasing gestational age, and female gender of the infant were protective prenatal or perinatal factors. Antepartum hemorrhage, the presence of labor, and breech presentation were perinatal factors that were associated with an increased risk of ICH. By using staged logistic regression, a model of combined prenatal and perinatal characteristics that influenced grade III and IV ICH was developed. Significant protective factors against ICH included a complete course of antenatal steroid therapy, African-American maternal race, female gender of the infant, hypertension or preeclampsia with no antepartum hemorrhage, increasing gestational age, and increasing birth weight. CONCLUSION: Antenatal steroid administration is a therapeutic intervention that is associated with a decreased risk for neonatal grade III and IV ICH.

Analysis of Variance↗
PubMed1994

Risk and protective factors for disruptive behavior disorders in children.

Biological, psychological, and social risk and protective factors in the development of disruptive behavior disorders were assessed in 50 disordered and 50 control preadolescents. Significant risk factors included learning difficulties, hyperactivity, perinatal complications, and violence in the home. Significant protective factors included ability to express feelings and a good relationship with grandparents.

Attention Deficit Disorder with Hyperactivity↗
PubMed2005

Measurement of sunscreen immune protection factors in humans: a consensus paper.

It is increasingly accepted that sunscreens should protect against ultraviolet radiation (UVR)-induced immunosuppression, with an index of protection that can be compared with the sun protection factor (SPF). Five groups of immunoprotection researchers met to discuss the status of immune protection factor (IPF) evaluation in human skin in vivo. Current methods rely on a suncreen's inhibition of UVR-induced local suppression of the contact hypersensitivity (CHS) response or the delayed-type hypersensitivity (DTH) response, using either the induction or the elicitation arms of these responses. The induction arm of the CHS response has the advantage of being sensitive to a single sub-erythemal exposure of solar-simulating radiation (SSR) that allows a direct comparison with the SPF. This approach, which necessitates sensitization, requires a large number of volunteers and is too labor intensive and time consuming to become a routine method. The elicitation arm of the CHS or DTH responses exploits prior sensitization to contact or recall antigens and has the advantage of being possible to apply on small groups of volunteers. Some current protocols, however, require repeat SSR exposures, which invalidates a direct comparison with SPF that is based on a single exposure. There is a need for a new simpler method of IPF that will have to be validated against existing models.

Dermatitis, Contact↗
PubMedDate not supplied

Violence risk and protective factors among youth held back in school.

OBJECTIVE: To identify risk and protective factors for violence perpetration among youth with a history of grade retention. DESIGN: Longitudinal analysis of in-home interviews of 13,781 adolescents in grades 7 through 12 conducted in 1995 and 1996. METHODS AND MEASURES: Serious interpersonal violence perpetration at time 2 by time 1 independent variables including measures of community and school context, family context, and individual characteristics. RESULTS: The 20% of girls and 28% of boys who had repeated 1 or more grades were more likely than those who had not to be in the top quintile of violence perpetration at time 2 (P <.001). For both girls and boys with a history of grade repetition, predictive risk factors with an odds ratio of 3 or greater (P <.001) included time 1 violence perpetration, violence victimization, weapon carrying, school problems, and alcohol and marijuana use. Although a high grade point average was a significant protective factor against violence perpetration for both girls (odds ratio, 0.36; P <.05) and boys (odds ratio, 0.23; P <.001), performance on a validated measure of verbal knowledge was not associated with violence perpetration over the study period. School connectedness, parent-family connectedness, and emotional well-being were also significant universal protectors against violence perpetration. CONCLUSIONS: Youth who are held back in school are at heightened risk for violence perpetration. Violence-related behaviors and substance use considerably increase the likelihood of this outcome. The findings suggest that schools can participate in violence prevention by providing youth with a positive community and academic experience.

Adolescent↗
PubMedDate not supplied

Sunbathers' application of sunscreen is probably inadequate to obtain the sun protection factor assigned to the preparation.

The sun protection factor (SPF) is a ratio that estimates the protective efficacy of a sunscreen against sunburn. The generally accepted methods used to determine the SPF of a sunscreen require that the formulation be applied in a thickness of 1.5 mg/cm2 (Deutsches Institut für Normung) or 2 mg/cm2 (US Food and Drug Administration). The applied thickness of a sunscreen is important for the degree of photoprotection. Forty-two volunteers on a beach applied their own sunscreen all over the body. The amount of the applied sunscreen was on average 0.5 mg/cm2. This indicates that the labelled SPF is probably considerably higher than the obtained degree of protection against sunburn.

Adolescent↗
PubMed2005

Meaningful workplace protection factor measurement: experimental protocols and data treatment.

Workplace performance measurement of respiratory protective equipment (RPE) is fundamental to the understanding of how well wearers are protected. It forms the basis for guidance on which the selection of appropriate equipment is based. However, the measurement of this performance is open to many sources of interference and inaccuracy, reducing the value and relevance of the results, and is most difficult for devices providing the highest levels of protection. In this paper, a method for critically assessing collected workplace protection factor (WPF) data is validated. This method rejects unreliable data, using criteria based on the detection limits of the analytical measurement system. An iterative approach is also described which arrives at a supportable estimate of given non-parametric percentiles of the distribution of measured WPFs [such as the fifth percentile, conventionally taken to be the assigned protection factor (APF)]. Further pragmatic criteria, based on a combination of experimental experience and consideration from first principles, are suggested as the basis for any future studies of RPE performance. These will maximize the chances of valid measurements being made, and also provide insight into the level of confidence which can be placed on any of the results. A consequence of these criteria is that typical working environments and measurement methods are incapable of generating WPF data which can be considered reliable.

Calibration↗
PubMed1976

Measurement of protection factors of chemical cartridge, half-mask respirators under working conditions in a copper smelter.

The performance of three commonly used chemical cartridge respirators for SO2 was measured under working conditions in a copper smelter. An effective SO2 protection factor for each man-respirator trial was calculated as the ratio between average SO2 concentrations sampled outside the respirator mask and that simultaneously sampled from inside the mask. The in-use SO2 protection afforded by the three respirators proved to be highly variable with mean protection factors of 22, 18, and 13. The distributions of the protection factors and the effects of mask type, facial size, and mask comfort are discussed.

Air Pollutants, Occupational↗
PubMed2006

Influence of applied quantity of sunscreen products on the sun protection factor--a multicenter study organized by the DGK Task Force Sun Protection.

It is often debated that the protection against solar-induced erythema under real conditions is dependent upon the amount of sunscreen applied. It is believed that when too little is applied a lower sun protection than indicated on the label will result. The aim of this study was to quantify this effect. In this multicenter study, the influence of three different amounts (0.5, 1.0, 2.0 mg/cm(2)) of three commercial sunscreen products in three reliable test centers was investigated according to the test protocol of The International Sun Protection Factor Test Method. The main result was a linear dependence of the SPF on the quantity applied. Taking into consideration the volunteer-specific variations, an exponential dependence of confidence interval of the in vivo SPF and amount applied was found. The highest amount applied (2.0 mg/cm(2)) was linked to the lowest confidence intervals. Thus, from the point of view of producing reliable and reproducible in vivo results under laboratory conditions, the recommendation of this multicenter study is an application quantity of 2.0 mg/cm(2).

Confidence Intervals↗
PubMed1976

Phytochrome Stability in Vitro: II. A Low Molecular Weight Protective Factor.

The decay in vitro of crude and purified phytochrome preparations, measured as decline in spectrophotometrically detectable photoreversibility, can be retarded by the addition of an as yet unidentified "protective factor" from the green tissue of peas. The factor has an apparent molecular weight of 465, is stable at elevated temperatures and to oxygen and high light intensity. It confers optimal protection at pH about 7.8 and is not greatly affected by treatment with hydrolytic enzymes. Protective factor also protects phytochrome against accelerated decay resulting from the addition of Cu(2+); it may therefore function as a metal chelator.

Journal Article↗
PubMed1999

Identifying families with likely genetic protective factors against Alzheimer disease.

Elderly individuals who lived beyond the age of 90 years without dementia were hypothesized to have increased concentrations of genetic protective factors against Alzheimer disease (AD), conferring a reduced liability for this disease relative to less-aged nondemented elderly. However, testing this hypothesis is complicated by having to distinguish such a group from those who may lack genetic risk factors for AD, have had protective environmental exposures, or have escaped dementia for other reasons. Probands carrying genetic protective factors, however, should have relatives with lower illness rates not only for earlier-onset disease, when genetic risk factors are a strong contributing factor to the incidence of AD, but also for later-onset disease, when the role of these factors appears to be markedly diminished. AD dementia was assessed through family informants in 6,660 first-degree relatives of 1,049 nondemented probands aged 60-102 years. The probands were grouped by age (60-74, 75-89, and 90-102 years), and the cumulative survival from AD and 10-year-age-interval hazard rates of AD were calculated in their first-degree relatives. Cumulative survival from AD was significantly greater in the relatives of the oldest proband group (aged 90-102 years) than it was in the two younger groups. In addition, the reduction in the rate of illness for this group was relatively constant across the entire late life span. The results suggest that genetic factors conferring a lifelong reduced liability of AD may be more highly concentrated among nondemented probands aged >/=90 years and their relatives. Efforts to identify protective allele-bearing genes that are associated with very late-onset AD should target the families of nonagenarians and centenarians.

Aged↗