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PubMed1987

Race categorization and face recognition stages in the processing of laterally displayed unknown faces.

Bruyer and Dussart (1985) have recently shown that the "race effect", i.e. the difficulty in recognizing faces issuing from an ethnic group different from that of the subject, is limited to the right visual field. They suspected familiarization to be responsible for this asymmetry. In Exp. I, we tested this hypothesis by repeating the experiment of Bruyer and Dussart with a greater number of trials. A sample of 16 subjects were given the task of recognizing black and white faces laterally displayed for 180 msec. No laterality effect appeared, and the race effect was observed to an equal degree in each hemifield at all stages of the experimental session. It could thus be that various kinds of familiarization must be distinguished. In Exp. II, with 16 new subjects, the black and white faces were mixed so that the subjects had first to perform racial categorization, then a recognition. This time, an advantage of the left field appeared, the race effect was larger in the right than in the left field, and the race effect decreased with familiarization in the left field only. Two complementary experiments with 24 and 16 subjects showed that this phenomenon was not explainable by laterality effects in the early racial decision operation, but well by a lateralized effect of tasks requirements.

Adult↗

PubMed2000

Changes in urine 8-hydroxydeoxyguanosine levels of super-marathon runners during a four-day race period.

We have determined the urinary 8-hydroxydeoxyguanosine (8-OHdG) levels of five well trained supra-marathon runners during a four-day race. The daily running distances of the four-day race were the following; 93 km, 120 km, 56 km and 59 km, respectively. Pre-race and post-race urine samples were collected on each day and analyzed by a monoclonal antibody technique. The urinary 8-OHdG content increased significantly on the first day and tended to decrease from the third day. By the fourth day 8-OHdG content was significantly less than measured on the first three days. The serum creatine kinase activity changed in a similar fashion, showing a large increase (P<0.001) up to the third day when it decreased significantly from the peak value (P<0.05). We conclude that extreme physical exercise causes oxidative DNA damage to well trained athletes. However, repeated extreme exercise-induced oxidative stress does not propagate on increase of urinary 8-OHdG, but rather causes an adaptation leading to normalization of oxidative DNA damage.

8-Hydroxy-2'-Deoxyguanosine↗

PubMed1996

Effect of acute induced metabolic alkalosis on the acid/base responses to sprint exercise of six racing greyhounds.

To investigate the effect of acute induced metabolic alkalosis on the haematological, biochemical and metabolic responses to sprint exercise, six greyhound dogs with previously placed carotid arterial catheters were raced four times over a distance of 400 metres. Each dog was raced twice after receiving oral sodium bicarbonate solution (NaHCO3) (400 mg kg-1) or lactated Ringer's solution (LRS). Before, and for intervals of up to one hour after, the exercise arterial blood samples were collected for the measurement of blood gases, packed cell volume, total protein, serum biochemistry and plasma lactate. The time to complete the 400 metre sprint ranged from 32.7 seconds to 36.9 seconds. There was no significant difference in racing times between the dogs treated with NaHCO3 and LRS, and there was no significant difference between the plasma lactate measurements after the treatments with NaHCO3 or LRS. Serum chloride concentrations were significantly lower after NaHCO3 than after LRS, and there was a trend towards a lower serum potassium concentration after NaHCO3 treatment. Plasma lactate concentrations showed a similar increase and time course of disappearance after both LRS and NaHCO3 treatments. There were significant changes in all the parameters measured after the exercise, but there were large variations between individual dogs and between races when the dogs were receiving the same treatment.

Acid-Base Equilibrium↗

PubMed2000

Race is not an independent predictor of biochemical recurrence after radical prostatectomy in an equal access medical center.

OBJECTIVES: To compare the racial differences in clinical and pathologic features between black and white men who underwent radical prostatectomy (RP) in an equal access health care center and to determine whether race is an independent predictor of biochemical recurrence. METHODS: A retrospective survey of 273 patients (125 black, 148 white) who underwent RP at the West Los Angeles Veterans Affairs Medical Center between 1991 and 1999 was undertaken. Patients were analyzed for racial differences in age at diagnosis, clinical stage, preoperative serum prostate-specific antigen (PSA), and Gleason score of the prostate biopsy specimens. Surgical specimens were studied to determine pathologic stage, Gleason score, incidence of seminal vesicle invasion, positive surgical margins, capsular penetration, and pelvic lymph node involvement. Patients were followed for PSA recurrence (greater than 0.2 ng/mL). Multivariate analysis was used to determine the clinical and pathologic variables that were significant in predicting biochemical recurrence after RP and to determine whether race was an independent predictor of biochemical failure. RESULTS: No significant differences were found between black and white men in the preoperative factors (clinical stage, age at diagnosis, biopsy Gleason score, and serum PSA) or in the pathologic features of the RP specimens (Gleason score, pathologic stage, incidence of positive surgical margins, capsular penetration, seminal vesicle invasion, or lymph node involvement). In addition, no differences were found between black and white men in the PSA recurrence rates after RP using Kaplan-Meier survival curves (P = 0.651). Multivariate analysis revealed that serum PSA (P = 0.010), biopsy Gleason score (P = 0. 003), younger age (P = 0.010), surgical Gleason score (P = 0.005), and lymph node involvement (P = 0.022) were all independent predictors of biochemical recurrence. Race was not a significant predictor of biochemical failure in multivariate analysis (P = 0. 199). CONCLUSIONS: In an equal access medical care facility, no differences were evident between black and white men in the preoperative clinical factors or the pathologic features of the RP specimens. In addition, no differences were observed in the PSA recurrence rates after RP. Serum PSA, biopsy Gleason score, younger age, surgical Gleason score, and lymph node involvement were all independent predictors of biochemical recurrence. Race was not an independent predictor of biochemical recurrence.

Black People↗

PubMed1999

Race is not independently associated with a positive prostate biopsy in men suspected of having prostate cancer.

OBJECTIVES: To examine whether race is associated with the prostate biopsy result after controlling for other clinical factors in men undergoing ultrasound-guided prostate biopsy to evaluate an elevated serum prostate-specific antigen (PSA) or an abnormal digital rectal examination (DRE), or both. METHODS: We reviewed the records of all men undergoing transrectal ultrasound-guided prostate biopsy at our facilities from January 1990 through March 1998. This included 1056 white men and 874 black men. Patient age, serum PSA, indication for prostate biopsy, and race were examined for association with the biopsy result. RESULTS: Of the 1 930 black and white men who underwent prostate biopsy, 639 (33%) had cancer, including 355 (41%) of 874 black men and 284 (27%) of 1056 white men. Serum PSA, abnormal DRE, and age were independent predictors of a prostate biopsy being positive for cancer. Race was not an independent predictor of cancer being identified in the prostate biopsy. CONCLUSIONS: After controlling for PSA, DRE, and age, black men were not at an increased risk of a positive prostate biopsy relative to white men. Our data do not support the need to consider race when estimating the probability that a man has prostate cancer.

Adult↗

PubMed1996

Socioeconomic status and race as risk factors for cockroach allergen exposure and sensitization in children with asthma.

BACKGROUND: The domestic cockroach has been identified as an important source of indoor aeroallergens worldwide in both temperate and tropical climates. Because cockroach populations are highest in crowded urban areas, some have suggested that the increased asthma morbidity and mortality rates in inner cities could be related in part to cockroach allergen exposure. We have examined cockroach allergen exposure in the homes of children with asthma in both urban and suburban locations and have related the rates of exposure and sensitization to socioeconomic, racial, and demographic factors. OBJECTIVE: The study was designed to determine the independent contribution of race, socioeconomic status, and place of residence to the risk of cockroach allergen exposure and sensitization in children with asthma. METHODS: Eighty-seven children with moderate to severe allergic asthma, aged 5 to 17 years, participating in a prospective trial of immunotherapy, were evaluated. Extracted dust samples from three home locations were analyzed by using two-site monoclonal immunoassays for major cockroach allergens (Bla g 1 and Bla g 2). A puncture skin test with a mixed cockroach allergen extract was performed in 81 of the 87 subjects. RESULTS: In the 87 homes evaluated, 26% of the bedroom dust samples had detectable levels of cockroach allergen. In homes with detectable bedroom cockroach allergen levels, mean Bla g 1 and Bla g 2 concentrations in urban and suburban homes were similar. Over 80% of children with bedroom Bla g 1 or Bla g 2 of 1 U/gm or greater demonstrated skin sensitivity to cockroach allergen. The rate of cockroach sensitization was directly related to the level of bedroom exposure. African-American race was the only factor that was independently associated with cockroach allergen exposure (p = 0.05). Lower socioeconomic status, age greater than 11 years, cockroach exposure, and African-American race were all independently associated with cockroach allergen sensitization on the basis of stepwise multiple linear regression analysis. CONCLUSIONS: African-American race and low socioeconomic status were both independent, significant risk factors for cockroach allergen sensitization in children with atopic asthma. Cockroach allergen is detectable throughout the house, including the critical bedroom environment.

Adolescent↗

PubMedDate not supplied

Effects of age and race on skin condition and bacterial counts on hands of neonatal ICU nurses.

OBJECTIVE: The purpose of this study was to assess the relationship between demographic factors such as age and race and skin condition and bacterial counts on hands of nurses. METHODS: Nurses (n = 111) working in 1 of 2 neonatal ICUs in New York City were surveyed regarding reported hand care practices and demographics, the condition of their hands was assessed by a trained observer and by themselves using validated instruments, and a hand culture was obtained. RESULTS: There were no significant differences in any skin care practices by race, but nurses who wore powder-free gloves were significantly younger than those who did not (P =.004). There were no significant differences in bacterial counts on hands of black or white nurses (mean log colony-forming units 3.49 and 3.61 respectively, P =.63) and no significant correlation between age and microbial counts (r = 0.04, P =.72). In a logistic regression analysis, race, but not age, was a significant predictor of skin health. By both observer (P =.02) and self-assessment (P =.004) black nurses had healthier skin. CONCLUSION: Physiochemical differences in skin associated with demographic factors such as age and race may be exacerbated among those in disciplines such as nursing, for whom the skin of the hands is continually stressed by occupational practices such as frequent hand hygiene. Such demographic factors need be considered when assessing skin condition and when advocating for appropriate strategies to maximize skin health. The recommendations of the new CDC Hand Hygiene Guideline for Healthcare Settings(23) regarding maintaining skin health and providing moisturizers and products that are milder to the skin are timely and should be followed.

Adult↗

PubMed1992

Demographics of emergency medical care at the Indianapolis 500 mile race (1983-1990).

BACKGROUND: The Indianapolis 500 Mile Race, the largest single-day, single-venue sporting event in the world, is attended by an estimated 400,000 people. Major illness and injury are treated at the Hanna Emergency Medical Center, the track hospital. Minor illness is treated at ten outlying aid stations. PURPOSE: We describe the demographics of emergency medical care at the Hanna Emergency Medical Center. DESIGN: Descriptive. METHODS: Patient care data for patients treated at the medical center are first recorded on paper charts and then coded and transferred to computer. Data regarding patients treated at the medical center during eight consecutive races (1983-1990) were analyzed. Frequency of treatment and medical cardiac arrest rates were calculated. Aid station data and medical center records from nonrace days were not analyzed. RESULTS: The average number of patients treated per year at the track hospital was 139. The total number treated over the eight-year period was 1,113, yielding a frequency of treatment of 0.35 per 1,000. Analysis showed 16.2% of the proprietary treatment codes involved intoxication; 15.4%, lacerations (other than feet); 11.0%, pre-existing conditions; and 8.5%, heat illness. During the eight years, there were four medical cardiac arrests (incidence of 0.0125 per 10,000 spectators), all resulting in death. A fifth spectator died after being struck by a wheel from a race car. There were no driver deaths on race day. CONCLUSION: Descriptive data regarding medical care of crowds may be useful to emergency specialists who must staff, order supplies, and plan treatment facilities for similar mass gatherings. It is evident from this and other mass-gathering studies that there is a need for consistency in nomenclature and data collection. This will allow more accurate comparisons of emergency medical care between venues.

Automobiles↗

PubMed1998

Race and survival after out-of-hospital cardiac arrest in a suburban community.

STUDY OBJECTIVE: To determine whether race, when controlled for income, is an independent predictor of survival to hospital discharge after out-of-hospital cardiac arrest (OHCA). METHODS: Prospective OHCA data were collected over 4 years (1991-1994) from a convenience sample of OHCA patients transported to nine hospitals in three suburban counties. Race was determined from hospital and vital statistics records. The average household income was identified from ZIP codes and used as a marker of socioeconomic status. Demographic data and known predictors of survival were compared between blacks and whites. A logistic regression analysis was used to assess the association between race, income, and survival. RESULTS: Of the 1,690 patients, 223 (13%) were blacks and 1,467 (87%) were whites. Average household income was less for blacks than for whites ($40,225 versus $46,193; P < .001), but both populations were affluent by national standards (national percentile ranks were 73% and 88%, respectively). The populations were no different in percentage of witnessed arrests (57% versus 61%; P = .465). Blacks were younger (mean +/- SD, 62 +/- 16 versus 68 +/- 15 years; P < .001); less frequently received bystander CPR (11% versus 20%; P = .002); less often had ventricular tachycardia or ventricular fibrillation (37% versus 50%; P < .001); and had a shorter advanced life support call-response interval (median, 4 versus 6 minutes; P < .001). The odds ratio for survival (white/black) was .931 (95% confidence interval, .446 to 1.945). CONCLUSION: Race was not found to predict adverse OHCA outcomes in this affluent population.

Black or African American↗

PubMed2001

Race, ethnicity and pain.

The current paper provides a brief overview of research on the effects of race and ethnicity on pain. More specifically, the article reviews the utility of the concepts of race and ethnicity for pain research, suggests operational definitions of race and ethnicity, reviews the literature on the effects of race and ethnicity on laboratory and clinical pain, and provides suggestions for future research.

Black or African American↗

PubMed2002

Prognostic significance of race on biochemical control in patients with localized prostate cancer treated with permanent brachytherapy: multivariate and matched-pair analyses.

PURPOSE: To compare PSA relapse-free survival (PSA-RFS) between African-American (AA) and white American (WA) males treated with permanent prostate brachytherapy (PPB) for clinically localized prostate cancer. METHODS AND MATERIALS: One thousand eighty-one consecutive patients, including 246 African-Americans, underwent PPB with 103Pd or 125I, alone or with external beam radiation therapy between September 1992 and September 1999. Computer-generated matching was performed to create two identical cohorts of WA and AA males, based on the use of neoadjuvant androgen ablation (NAAD), pretreatment PSA, and Gleason score. Presenting characteristics were used to define risk groups, as follows: Low risk had PSA 10 or Gleason score >or=7, and high risk had PSA >10 and Gleason score >or=7. PSA-RFS was calculated using the Kattan modification of the ASTRO definition, and the log-rank test was used to compare Kaplan-Meier PSA-RFS curves. Univariate and multivariate analyses were performed to determine predictors of PSA-RFS. RESULTS: Overall, univariate analysis revealed that AA males at presentation had lower disease stage (p = 0.01), had lower Gleason scores (p = 0.017), were younger (p = 0.001), and were more likely to receive NAAD (p = 0.001) than their WA counterparts. There were no differences in pretreatment PSA, isotope selection, use of external beam radiation therapy, median follow-up, or risk group classification between AA and WA males. Pretreatment PSA and Gleason score were significant predictors of PSA-RFS in multivariate analysis, and race was not significant. There was no significant difference between the 5-year PSA-RFS for AA males (84.0%) and the matched cohort of WA males (81.2%) (p = 0.384). Race was not a predictor of 5-year PSA-RFS among patients treated with or without NAAD and within low-, intermediate-, and high-risk groups. CONCLUSION: Race is not an independent predictor of 5-year PSA-RFS in patients with localized prostate cancer treated with PPB. This result is consistent with other studies that also show that race does not contribute to differences in outcome after definitive therapies for localized prostate cancer.

Adult↗

PubMed2003

The association between presentation PSA and race in two sequential time periods in prostate cancer patients seen at a university hospital and its community affiliates.

PURPOSE: We sought to determine whether African American men diagnosed with prostate cancer in the prostate-specific antigen (PSA) era differed in initial presenting serum PSA levels (iPSA) compared to white men. Recent retrospective studies have demonstrated higher iPSA within the African American men than in white men at the time of diagnosis, suggestive of more advanced disease in African American men. Both biologic differences and/or sociologic factors have been postulated as explaining the noted differences in iPSA. We reviewed our institution's PSA-era experience to determine any association between race and iPSA. MATERIALS AND METHODS: Between January 1990 and September 2001, 4519 patients representing a broad demographic sample were seen in the radiation oncology department of a university hospital or one of its four community affiliates. A total of 2332 eligible patients, with data on race, age, year of diagnosis, Gleason score, T stage, and iPSA, were analyzed. The patients were separated into the two following time periods for analysis, based on the new American Cancer Society screening guidelines: (1) 1991 to 1996 and (2) 1997 to 2001. The relationships between race and iPSA, T stage, Gleason score, and age are explored. RESULTS: Of the 2332 patients analyzed, there were 1968 white men and 364 African American men. For the time period 1990 through 1996, the expected average (median) iPSA level was 10.5 (10.2) and 14.6 (15.8) for white men and African American men, respectively. For 1997 to 2001, the expected average iPSA level was 9.5 (8.4) and 10.8 (9.8), respectively. T stage distributions improved, independent of race, toward earlier stage at presentation. Gleason score distribution remained unchanged. African American men are 2.5-3.1 years younger than white men at diagnosis. CONCLUSIONS: An overall decline in iPSA has occurred in both racial groups over time. More importantly, racial differences in iPSA among men diagnosed in the later time period (1997 to 2001) are less pronounced compared to men diagnosed in the earlier time period (1990 to 1996). This racial convergence in iPSA over time suggests improved penetrance of PSA screening in the African American population. Our findings also suggest that studies comparing racial differences in iPSA should consider time period of diagnosis and possible sociologic changes during that period (i.e., access to medical care, socioeconomic status, and educational level). The American Cancer Society guideline to begin screening African Americans at an earlier age is appropriate.

Black or African American↗

PubMed1999

The impact of race on biochemical disease-free survival in early-stage prostate cancer patients treated with surgery or radiation therapy.

PURPOSE: To assess the impact of race on biochemical freedom from recurrence in patients with early-stage prostate cancer treated either by radical prostatectomy or radiation therapy. METHODS: Between July 1989 and December 1994, 693 patients with early-stage prostate cancer were treated with radiation (302 patients) or by radical prostatectomy (391 patients) at Barbara Ann Karmanos Cancer Institute/Wayne State University. Stage, Gleason score, race, pretreatment PSA, and follow-up PSA values were abstracted. There were 387 Caucasian males (CM) and 306 African-American males (AAM). None of the patients received hormone therapy. Radiation therapy was delivered using photon irradiation (249 patients, median dose 69 Gy) or mixed neutron/photon irradiation (53 patients, median dose 10 NGy + 38 PGy). Median follow-up was 36 months (range 2-70) for CM and 35 months (range 1-70) for AAM. RESULTS: Thirty-seven percent of patients treated surgically were AAM, compared to 53% in the radiation group (p = 0001). AAM had a higher median prostate-specific antigen (PSA) than CM (9.78 ng/ml vs. 8.0 ng/ml, p = 0.01). Thirty-three percent of AAM had a pretreatment PSA greater than 15 ng/ml compared to 20% of CM (p = 0.00001). Disease-free survival (DFS) by race was equivalent at 36 months, 81% for CM and 77% for AAM (p = NS). For patients with PSA < or =15, DFS rates were 87% and 85% for CM and AAM, respectively. DFS rates for patients with PSA >15 were 61% for CM and 64% for AAM (p = NS). Significant prognostic factors on multivariate analysis included pretreatment PSA (p = 0.0001) and Gleason score (p = 0.0001). CONCLUSION: Race does not appear to adversely affect biochemical disease-free survival in males treated for early-stage prostate cancer. African-American males with early-stage prostate cancer should expect similar biochemical disease-free survival rates to those seen in Caucasian males.

Black People↗

PubMed1998

Beyond black, white and Hispanic: race, ethnic origin and drinking patterns in the United States.

This study used data on 42,862 U.S. adults, including 18,352 past-year drinkers, to describe differentials by race and national origin in U.S. drinking patterns. Age-sex standardized estimates were presented within 21 categories of ethnic origin for whites and within five categories each for individuals of black and other races. Of the three racial groups, whites were the most likely to drink, but blacks had the highest volume of intake and frequency of heavy drinking. Differences by ethnic origin within racial categories were as marked as differentials between races. Compared to whites of European origin, those of Hispanic and native American origin were less likely to drink but consumed more alcohol on days when they drank. Whites of Southern and Eastern European origin drank proportionately more wine and demonstrated more moderate drinking patterns (lower intake per drinking day and/or less frequent heavy drinking) than those of Northern or Central European origin. Hispanics of Caribbean origin were less prone to heavy drinking than other white Hispanics; similarly, blacks from the English-speaking Caribbean showed more moderate drinking patterns than other blacks. Individuals of Asian origin, in particular those of non-Japanese origin, had the most moderate drinking patterns within the category of other race. Although the black/white differentials in volume of intake and frequency of heavy drinking disappeared after adjusting for marital status, education and income, most of the differences by ethnic origin retained their statistical significance if not their original magnitudes. These findings indicate that cultural forces exert a strong effect on drinking behavior. Differences among European whites with respect to prevalence of drinking, beverage preference and frequency of heavy drinking suggest that the association between ethnic origin and drinking behavior may persist even after many generations of presumed acculturation.

Acculturation↗

PubMed2002

Impedance vector distribution by sex, race, body mass index, and age in the United States: standard reference intervals as bivariate Z scores.

Bioelectrical impedance measurements were collected in the Third National Health and Nutrition Examination Survey (NHANES III), but their results have not been published. In the NHANES III population, resistance (R) and reactance (Xc) values at 50-kHz frequency were obtained with a Valhalla Scientific meter (model 1990B; San Diego, CA, USA). The RXc graph method was used to identify bivariate pattern distributions of mean vectors (95% confidence ellipses by sex, race, age, and body mass index [BMI]), and individual impedance vectors (50%, 75%, and 95% tolerance ellipses). Data from 10 222 adults (5261 men and 4961 women) formed 90 four-way classification groups, with two sexes, three races or ethnicities (non-Hispanic white, non-Hispanic black, Mexican American), five age classes (20-29, 30-39, 40-49, 50-59, and 60-69 y), and three BMI classes (19-24.9, 25-29.9, and 30-34.9 kg/m(2)). Sex, race or ethnicity, BMI and age, in decreasing order, influenced the vector distribution pattern. Mean vectors in women were significantly longer than those in men. Within each sex, the mean vector of non-Hispanic white subjects was shorter and with a smaller phase angle than that of corresponding BMIs from the two other race/ethnic populations. Tolerance ellipses were calculated from sex- and race-specific reference populations 20 to 69 y old and 19 < or = BMI < 30 kg/m(2) (8022 subjects, 4226 men and 3796 women). After transformation of impedance vector components into bivariate Z scores (standardized deviates, as differences from the mean divided by the standard deviation of the reference population), we constructed one standard, reference, RXc-score graph (50%, 75%, and 95% tolerance ellipses) that can be used with any analyzer in any population. The pattern of impedance vector distribution and reference bivariate intervals for the individual impedance vector are presented for comparative studies (free software at E-mail: apiccoli@unipd.it).

Adult↗

PubMed2002

The three-dimensional model of Dictyostelium discoideum racE based on the human rhoA-GDP crystal structure.

The three-dimensional structure of racE was modeled using several homologous small G proteins, and the best model obtained using the human rhoA as modeling template is reported. The three-dimensional fold of the racE model is remarkably similar to the cellular form of human ras p21 crystal structure. Its secondary structure consists of six alpha-helices, six beta-strands and three 3(10) helices. The model retains its secondary structure after a 300 K, 300 ps molecular dynamics (MD) simulation. Important domains of the protein include its effector loop (residues 34-46), the insertion domain (residues 121-136), and the polybasic motif (between 210 and 220) not modeled in the current structure. The effector loop is inherently flexible and the structure docked with GDP exhibits the effector loop moving significantly closer to the nucleotide binding pocket, forming a tighter complex with the bound GDP. The mobility of the effector loop is conferred by a single residue 'hinge' point at residue 34Asp, also allowing the Switch I region, immediately preceding the effector loop, to be equally mobile. In comparison, the Switch II region shows average mobility. The insertion domain is highly flexible, with the insertion taking the form of a helical domain, with several charged residues forming a complex charged interface over the entire insertion region. While the GDP moiety is loosely held in the active site, the metal cation is extensively co-ordinated. The critical residue 38Thr exhibits high mobility, and is seen interacting directly with the metal ion at a distance of 2.64 A, and indirectly via an intervening water molecule. 64Gln, a key residue involved in GTP hydrolysis in ras, is seen facing the beta-phosphate group and the metal ion. Certain residues (i.e. 51Asn, 38Thr and 65Glu) exhibit unique characteristics and these residues, together with 158Val, may play important roles in the maintenance of the protein's integrity and function. There is strong consensus of secondary structural elements between models generated using various templates, such as h-rac1, h-rhoA and h-cdc42 bound to RhoGDI, all sharing only 50-55% sequence identity with racE, which suggests that this model is in all probability an accurate prediction of the true tertiary structure of racE.

Amino Acid Sequence↗

PubMed2001

Role of exercise and ascorbate on plasma antioxidant capacity in thoroughbred race horses.

During exercise, the oxygen consumption and the production of free radicals increase and can lead to oxidative stress with a deleterious effect on cellular structures involved in physical activity. To evaluate the oxidative stress produced by exercise and the role of ascorbate as an antioxidant, venous blood samples were obtained from 44 thoroughbred racehorses, before and after a 1000+/-200-m race at maximum velocity. Fourteen of these horses were treated intravenously with 5 g of ascorbate before running. Antioxidant capacity (PAOC), endogenous and exogenous ascorbate concentration, total antioxidant reactivity (TAR), urate concentration, creatine kinase activity, protein concentration and thiobarbiturate reactive substances (TBAR) as oxidative stress indicators were measured in the plasma of some of these horses. PAOC, TAR and TBAR increased after the race, while plasma ascorbate and urate concentrations remained unchanged. Total plasma protein (TPP) concentrations increased in line with antioxidant capacity. As predicted, both the plasma ascorbate concentration and PAOC increased immediately after ascorbate administration, but was not modified after the race, such as TBAR. However, in both groups plasma creatine kinase activity increased after the race. These results would suggest that the administration of ascorbate could nullify the oxidative stress produced by exercise in thoroughbred racehorses, but could not prevent muscular damage.

Animals↗

PubMed2005

Specifying race-ethnic differences in risk for psychiatric disorder in a USA national sample.

BACKGROUND: Epidemiological studies have found lower than expected prevalence of psychiatric disorders among disadvantaged race-ethnic minority groups in the USA. Recent research shows that this is due entirely to reduced lifetime risk of disorders, as opposed to persistence. Specification of race-ethnic differences with respect to clinical and social characteristics can help identify the protective factors that lead to lower lifetime risk among disadvantaged minority groups. METHOD: Data on 5424 Hispanics, non-Hispanic Blacks, and non-Hispanic Whites came from the National Comorbidity Survey Replication, a nationally representative survey conducted with the World Mental Health version of the Composite International Diagnostic Interview. Race-ethnic differences in risk of disorders were compared across specific diagnoses, ages of onset, cohorts and levels of education. RESULTS: Both minority groups had lower risk for common internalizing disorders: depression, generalized anxiety disorder, and social phobia. In addition, Hispanics had lower risk for dysthymia, oppositional-defiant disorder and attention deficit hyperactivity disorder; non-Hispanic Blacks had lower risk for panic disorder, substance use disorders and early-onset impulse control disorders. Lower risk among Hispanics, relative to non-Hispanic Whites, was found only among the younger cohort (age<or=43 years). Lower risk among minorities was more pronounced at lower levels of education. CONCLUSION: The pattern of race-ethnic differences in risk for psychiatric disorders suggests the presence of protective factors that originate in childhood and have generalized effects on internalizing disorders. For Hispanics, but not for non-Hispanic Blacks, the influence of these protective factors has emerged only recently.

Adolescent↗