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PubMed1956

Nephrotoxic serum nephritis in rats. II. Preparation and characterization of a soluble protective factor produced by trypsin digestion of rat tissue homogenates.

A soluble protective factor, capable of absorbing nephrotoxic antibodies from anti-rat kidney serum, can be obtained in high concentration by tryptic digestion of rat kidney homogenate. The factor is no longer antigenic or at most only slightly so. It is stable at 60 degrees , destroyed by boiling, is non-dialyzable, can be precipitated by ammonium sulfate, but resists destruction by proteolytic and other enzymes. In accord with previous studies on the organ localization of the rat tissue antigen responsible for the production of nephrotoxic antibodies, the soluble protective factor, or antigen derivative, can be obtained by tryptic digestion of rat lung, skeletal muscle, heart, and liver.

Animals↗
PubMed2006

The tools to understand: community as co-researcher on culture-specific protective factors for Alaska Natives.

A collaborative research process engaging Alaska Native communities in the study of protective factors in Alaska Native sobriety and the design of a preventative intervention using its findings is described. Study 1 was discovery oriented qualitative research whose objectives were identification of protective factors and development of a heuristic model. Study 2 involved quantitative survey methods to develop and test ameasure of protective factors identified by the qualitative study. Empirical data from these studies is presented, and the role of Alaska Native co-researchers who did not possess specialist research training is described in the design and implementation of the study, interpretation of findings, and design of the intervention model and tools. Benefits that emerged from co-researcher involvement in this process, to the community and to the co-researchers themselves, are described.

Adult↗
PubMed1996

Structure-based calculation of the equilibrium folding pathway of proteins. Correlation with hydrogen exchange protection factors.

A new statistical thermodynamic formalism has been developed in order to describe the equilibrium folding pathway of proteins. The resulting formalism allows calculation of the probabilities that individual amino acid residues will be in a native or native-like conformation for any given degree of folding of the protein molecule. The residue probabilities are defined by the probability distribution of conformational states and can be used to calculate experimental quantities like native-state, hydrogen exchange protection factors. A combinatorial algorithm aimed at generating a large ensemble of conformational states (10(4) to 10(6)) using the native structure as a template has been developed. The Gibbs energy and corresponding probability of each conformational state is estimated by using a previously developed structural parametrization of the energetics. The approach has been applied to five different proteins: hen egg-white lysozyme, equine lysozyme, bovine pancreatic trypsin inhibitor, staphylococcal nuclease and turkey ovomucoid third domain. The validity of the approach has been tested by comparing predicted and experimental hydrogen exchange protection factors. It is shown that for the above proteins 76%, 73%, 74%, 78% and 81% of all observed protection factors are predicted correctly. Furthermore, on average, the magnitude of the predicted protection factors, expressed as apparent free energies per residue deviate less than 1 kcal/mol from those obtained experimentally. These results represent the first attempt at predicting both the location and magnitude of hydrogen exchange protection factors from the high-resolution structure of a protein. The good agreement between experimental and predicted values has permitted a close examination of the nature of the equilibrium folding intermediates existing under conditions of maximal stability of the native state.

Animals↗
PubMed1995

Is alcohol-related flushing a protective factor for alcoholism in Caucasians?

Although alcohol-related flushing seems to be a genetically influenced protective factor for alcoholism in some Asian groups, little is known about whether this is true for Caucasians. The evidence for alcohol-related flushing as a protective factor for the development of alcoholism was examined in a sample of 5831 Australian twins (2041 men, 3790 women) who were administered a structured psychiatric interview. Twin correlations for self-reported adverse alcohol reactions (e.g., "flushing or blushing" and "feeling very sleepy" after drinking 1 or 2 drinks) were modest, suggesting minimal contribution of genetic factors, but when corrected for reliability of measurement, were consistent with moderate heritabilities. In accord with studies examining Asian samples, we found that individuals who experienced adverse reactions after drinking small amounts of alcohol drank less often and slightly less per drinking occasion than those who did not experience adverse reactions. However, those who experienced adverse reactions were more likely to have symptoms of alcoholism and to report a parental history of alcohol problems. We conclude that self-reported alcohol-related flushing is not a protective factor for alcoholism in Caucasians and may be a risk factor.

Adult↗
PubMed2002

Emotional and behavioural problems in childhood and distress in adult life: risk and protective factors.

OBJECTIVE: To assess the relationship between risk and protective factors and the continuity of psychological problems from age 7 to age 33. METHODS: Data on 5,591 cohort members of the National Child Development Study were used to track continuity and discontinuity between internalizing and externalizing problems at age 7, as assessed by the Rutter 'A' Health and Behaviour Checklist, and psychological distress at age 33, as assessed by the Malaise Inventory, controlling for risk and protective groupings present at age 7. RESULTS: There was no association between malaise in adulthood and internalizing problems in childhood. However, people who had externalizing problems in childhood were nearly twice as likely as those without such problems to have high Malaise scores in adulthood. A grouping of risk factors (police/probation experience by family, agency referral for difficulties in school, social services involvement, domestic tension) did not predict malaise in adulthood. Also a grouping of protective factors (outings with mother, father reads to child, good creative skills, good numeric skills) predicted that women were less likely to have high Malaise scores in adult life. CONCLUSIONS: Protective factors in childhood were strongly associated with lower Malaise scores in adulthood. Research on factors associated with discontinuity of psychological problems may prove fruitful.

Adaptation, Psychological↗
PubMed2000

Nerve growth factor protects oligodendrocytes from tumor necrosis factor-alpha-induced injury through Akt-mediated signaling mechanisms.

Tumor necrosis factor-alpha is thought to be one of the most important inflammatory cytokines associated with the demyelinating disease multiple sclerosis. We determined whether neurotrophins could protect oligodendrocytes from tumor necrosis factor-alpha-mediated cytotoxicity. Among the neurotrophins tested, nerve growth factor was most effective at preventing cell death. Nerve growth factor also prevented the tumor necrosis factor-induced loss of mitochondrial membrane potential. Overexpression of constitutively active Akt, a downstream target of phosphatidylinositol 3-kinase, but not of constitutively active MEK, protected oligodendrocytes from tumor necrosis factor-induced injury. Moreover, overexpression of dominant-negative Akt negated the protective effects of nerve growth factor on tumor necrosis factor-mediated oligodendrocyte cytotoxicity. These findings indicate that the Akt pathway is crucial in nerve growth factor-mediated oligodendrocyte protection.

Androstadienes↗
PubMed1996

An investigation of risk and protective factors in a sample of youthful offenders.

The study explored a set of potential risk and protective factors in relation to criminal activity and adjustment with a group of delinquent youths. The results indicated, first, that risk variables reflecting family relationship and parenting problems were associated with heightened rates of re-offending and lower overall adjustment. Second, the presence of protective factors relating to positive peer relations, good school achievement, positive response to authority and effective use of leisure time was associated with more positive outcomes with controls for the risk variables. Third, there was no evidence of interaction between risk and protective factors; the latter operated similarly at low and high levels of risk. These results are discussed in terms of their theoretical and applied significance.

Achievement↗
PubMed1999

Measurement of in vivo sunscreen immune protection factors in humans.

This study investigates the level of protection provided by sunscreens against solar-simulated UV radiation-induced immunosuppression in humans. The in vivo immune protection factors (IPF) of two broad-spectrum sunscreens were determined by assessing their ability to prevent UV-induced suppression of nickel contact hypersensitivity (CHS) in 15 nickel-allergic volunteers. Each volunteer was irradiated on unprotected skin of the back with different doses of UV daily for 4 days. Multiples of these UV doses were concurrently delivered to sunscreen-treated sites on the contralateral back. Nickel patches were then applied to both irradiated sites and adjacent, unirradiated control sites. Nickel-induced erythema at each site was measured 72 h later with a reflectance spectrometer. Comparison of the nickel reactions of irradiated and unirradiated skin revealed linear UV dose-responses for immunosuppression in both unprotected and sunscreen-treated skin. The minimum level of immunosuppression that can be reliably detected with this method is 20%. Therefore, the UV dose that reduces mean nickel CHS by 20% is the minimal immune suppression dose (MISD). Sunscreen IPF were determined by dividing the mean MISD of sunscreen-treated skin by that of unprotected skin. The sunscreens, with sun protection factors of 9 and 24, had IPF of 6.5 and > 25, respectively.

Adult↗
PubMed2004

Associations between adolescent drinking and driving involvement and self-reported risk and protective factors in students in public schools in Washington State.

OBJECTIVE: This study examines associations between self-reported drinking and driving or being a passenger of a drinking driver and risk and protective factors in a general population of adolescents. METHOD: We used a two-staged sampling procedure to survey 2,955 students in Washington State public schools in Grades 9-12. Students were asked if they were a passenger of, or had been, a drinking driver in the previous month. They were also asked about individual, parent, school and community risk and protective factors. Comparisons were made using hierarchical polychotomous logistic regression, entering age and gender and parent, school and community protective factors at the first step and individual risk factors at the second step. RESULTS: Driving after drinking in the previous month was reported by 12.1% of respondents and riding with a drinking driver was reported by an additional 17.6% of respondents. At the first step, driving after drinking was more likely and riding with a drinking driver was less likely among youth who were age 16 or older, and male students were more likely than female students to report driving after drinking. Parent, school and community support were each significantly associated with less driving after drinking, and school support was significantly associated with less riding with drinking drivers. At the second step, higher quantity and frequency of drinking, more smoking cigarettes and drug use and less seat belt use were each associated with both drinking and driving and riding with drinking drivers. Gun carrying was also associated with driving after drinking. CONCLUSIONS: Drinking and driving behaviors were associated with risk and protective factors in the community, school, family and individual. Pilot prevention programs should test the effectiveness of reducing drinking and driving involvement by addressing such factors.

Accidents, Traffic↗
PubMed2002

Prevalence and risk and protective factors related to disordered eating behaviors among adolescents: relationship to gender and ethnicity.

PURPOSE: To examine the current prevalence of disordered eating behaviors in a large sample of adolescents, by gender and ethnicity, and to identify gender and ethnic-specific risk and protective factors. METHODS: The study population included 81,247 9th- and 12th-graders who completed the 1998 Minnesota Student Survey, a self-report, school-based survey which included questions about disordered eating behaviors and a variety of psychosocial characteristics. RESULTS: Fifty-six percent of 9th-grade females and 28% of 9th-grade males report disordered eating behaviors (i.e. one or more of the following to lose or control weight: fasting or skipping meals, diet pills, vomiting, laxatives or smoking cigarettes; and binge-eating), with slightly higher rates among 12th-grade females and males, 57% and 31%, respectively. Among both genders, Hispanic and American Indian youth reported the highest prevalence of disordered eating. Risk factors for disordered eating among both males and females included cigarette smoking, appearance concerns, and alcohol use. Protective factors for both males and females were positive self-esteem, emotional well-being, school achievement, and family connectedness. While risk and protective factors were similar across gender, they differed across ethnicity particularly among females. CONCLUSIONS: Health professionals working with youth need to be aware of the high prevalence of these subclinical disordered eating behaviors, ask appropriate screening questions, and provide resources and referral, if necessary, for youth reporting these behaviors. Knowledge of risk and protective factors can serve to guide intervention and prevention efforts, particularly as they apply across ethnicity.

Adolescent↗
PubMed1997

Protective factors within the family, and their role in fostering resiliency in African American adolescents.

Violence has reached epidemic proportions in the United States, with African American males residing in urban areas bearing the brunt of this epidemic. The violence permeating our society emanates from a variety of societal ills, including poverty, racism, substance abuse and exposure to violence. Traditionally, methods of research on adolescent violence have focused on an identification of associated risk factors. The majority of African American adolescents living in communities with widespread and chronic violence grow up to be law-abiding citizens. The reason for this may be due to resiliency within these adolescents. Resiliency has been defined as the ability to experience adverse circumstances and successfully overcome them. Resiliency is enhanced through three mechanisms identified as protective factors: individual characteristics/traits; familial traits; and extrafamilial relationships. The risks faced may be altered, and even ameliorated, through the presence of these protective factors. The purpose of this paper is to identify protective factors within the family that foster resiliency. Protective factors within the family may be categorized as having three broad characteristics: caring and support, high expectations, and encouragement of participation and involvement for the adolescent.

Adaptation, Psychological↗
PubMed2004

Prediction of sun protection factors and UVA parameters of sunscreens by using a calibrated step film model.

At the stage of screening of new sun protection formulations, quick and inexpensive methods for estimation of the ultraviolet (UV) screening performance are highly desirable. It has been shown recently that apart from measurements of sun protection factors in vitro, calculations using a calibrated step film model are also a possibility. In the present investigation, further evidence for the usefulness of the step film model in terms of prediction of the sun protection factor is shown. In addition, it is demonstrated that parameters, which characterize the protection in the UVA range such as the UVA/UVB ratio and the critical wavelength can be calculated in good accordance with experimental data. Although with less accuracy, the estimation of UVA protection factors is also possible, if the photodegradation some filters undergo upon irradiation is taken into consideration.

Calibration↗
PubMed1993

Basic fibroblast growth factor protects cerebrocortical neurons against excitatory amino acid toxicity in vitro.

BACKGROUND AND PURPOSE: Previous studies have shown that basic fibroblast growth factor protects against excitatory amino acid toxicity in cultured hippocampal, striatal, and cerebellar neurons. In the current study, we examined the neuroprotective effects of this growth factor on cerebrocortical neurons, which are commonly involved in thromboembolic stroke. METHODS: Dissociated neuron-glia cultures of embryonic rat cerebral cortex (12 days in vitro) were preincubated with basic fibroblast growth factor (0.1 to 100 ng/mL) for 6 hours before incubation with glutamate (0 to 1000 mumol/L) for 16 hours. The number of phase-bright neurons was taken as an index of neuronal survival. RESULTS: Basic fibroblast growth factor protected neurons against glutamate toxicity, especially at lower (10, 25, and 50 mumol/L), but not higher (100 and 1000 mumol/L), glutamate concentrations. Neuroprotection was seen at growth factor doses as low as 1 ng/mL. CONCLUSIONS: Basic fibroblast growth factor protects cultured cerebrocortical neurons against glutamate neurotoxicity.

Analysis of Variance↗
PubMed1991

Exercise as a coronary protective factor.

Exercise has multiple beneficial actions, both in normal subjects and in patients with coronary artery disease, which can be cardioprotective. Apart from reducing known risk factors and protecting against their deleterious effects, exercise also reduces the risk of coronary artery disease by increasing cardiovascular fitness. The exact contribution of each of these mechanisms in reducing coronary artery disease morbidity and mortality is unclear. Although fitness may be desirable, much of the cardioprotection can be achieved through increased leisure time and recreational physical activity. The risk-benefit ratio is very much in favor of moderate intensity exercise. Even in the absence of a controlled trial, the available evidence suggests that efforts to encourage physical activity are justified.

Cardiovascular Physiological Phenomena↗
PubMed2001

Health-risk behaviors and protective factors among adolescents with mobility impairments and learning and emotional disabilities.

PURPOSE: To identify the risk involvement of three groups of young people with disabilities relative to a comparison group: mobility impairments, learning disabilities, and emotional disabilities. Protective factors are explored to identify which individual, family, and school factors are associated with diminished risk. METHODS: Analyses are based on the National Longitudinal Study of Adolescent Health (Add Health), a nationally representative sample of 20,780 seventh- through 12(th)-grade youth in the United States. Five negative health outcomes were studied: suicide attempts, sexual abuse, regular cigarette smoker, alcohol use, and marijuana use. For bivariate analyses Student's t-test and Chi-square were used, and logistic regressions were performed on all dichotomized dependent variables. RESULTS: For most risk behaviors studied, youth with disabilities were more involved than peers. Factors that predisposed to risk varied little between those with and without disabilities. Likewise, there was substantial consistency between groups as to protective factors. What distinguished each group of young people with disabilities from peers is that they reported significantly more exposure to risk factors and significantly fewer protective factors.

Adolescent↗
PubMed1992

Determination of program protection factors for half-mask respirators used at a mineral sands separation plant.

A study was conducted at a mineral sands separation plant to evaluate the workplace performance of half-mask filter cartridge respirators. Inhalation exposure was estimated by measuring the dust and radioactivity concentration inside the respirator while it was worn or hanging around the worker's neck. The program protection factor was determined by simultaneously measuring inside-mask and ambient (outside-mask) concentrations. A total of 27 tests were conducted, covering three brands of half-mask respirators; facial hair on test subjects ranged from clean-shaven to bearded. Program protection factors varied from 1.8 to 13 for dust exposure and 2.5 to 21 for radioactivity exposure. The geometric mean program protection factor over all tests was 5.1 (geometric standard deviation [GSD] = 1.7) for dust exposure and 7.5 (GSD = 1.7) for radioactivity exposure. A minimum program protection factor of 3.5 could be applied to ambient airborne concentration data to obtain a conservative, but more realistic, estimate of inhalation exposure on a worker category basis.

Air Pollutants, Radioactive↗
PubMed2003

Is the factor XIII 34Val/Leu polymorphism a protective factor for cerebrovascular disease?

A frequent polymorphism in the factor XIII (FXIII) A-subunit gene, leading to a Val to Leu amino acid exchange at position 34, suggested to affect clot stability, has been associated with a decreased risk for venous thromboembolism and myocardial infarction. Its role in the development of stroke is still under investigation. Ninety-four patients with primary arterial intracerebral haemorrhage (mean age +/- standard deviation: 69 +/- 14 years; 48 men, 46 women), 718 patients with ischaemic stroke (63 +/- 14 years; 395 men, 323 women) and 369 healthy control subjects (59 +/- 14 years; 299 men, 170 women) were analysed for FXIII Val34Leu. No differences in genotype distribution between all three groups were observed. Also, no significant differences in the genotype distribution were found between subgroups of patients stratified according to age, sex, aetiology, history of hypertension, antiplatelet or anticoagulant medication and other vascular risk factors. In contrast to previously reported findings in smaller collectives, our data suggest that an association of the FXIII Val34Leu polymorphism with a decreased risk of ischaemic stroke or an increased risk of intracerebral haemorrhage is highly unlikely. Thus, screening for the FXIII Val34Leu polymorphism will not contribute significantly to the risk prediction of cerebrovascular disease.

Adult↗