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Dive into the research topics where Kevin F. O'Brien is active.

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Featured researches published by Kevin F. O'Brien.


Journal of American College Health | 1985

Effects of Aerobic Training on Primary Dysmenorrhea Symptomatology in College Females

R. G. Israel; Miriam Sutton; Kevin F. O'Brien

Abstract “Single-Dose Therapy for Cystitis in Women: A Comparison of Trimethoprim-Sulfamethoxazole, Amoxicillin, and Cyclacillin,” Thomas M. Hooton et al. We evaluated single-dose regimens of trimethoprim-sulfamethoxazole, amoxicillin, and cyclacillin as treatment for acute cystitis in 38 women. The trial was prematurely stopped because of frequent treatment failures. At two days after treatment, all 13 patients given trimethoprim-sulfamethoxazole were cured, while four (31%) of the 13 given amoxicillin and four (33%) of 12 given cyclacillin had persistent bacteriuria. At two weeks, 11 (85%) of 13 patients given trimethoprim-sulfamethoxazole, six (50%) of 12 given amoxicillin, and three (30%) of ten given cyclacillin were cured. One patient with positive results of antibody-coated bacteria testing who was treated with cyclacillin had signs and symptoms of acute pyelonephritis three days after treatment, and two patients treated with amoxicillin and one treated with trimethoprim-sulfamethoxazole converted ...


Journal of Alternative and Complementary Medicine | 2010

Radioprotective Effect of American Ginseng on Human Lymphocytes at 90 Minutes Postirradiation: A Study of 40 Cases

Tung-Kwang Lee; Kevin F. O'Brien; Weidong Wang; Roberta M. Johnke; Chao Sheng; S Benhabib; Tao Wang; Ron R. Allison

BACKGROUND Ionizing radiation (IR) initiates intracellular oxidative stress through enhanced formation of reactive oxygen species (ROS) that attack DNA leading to cell death. Because of the diversity of IR applied in medicine, agriculture, industry, and the growing threats of global terrorism, the acquisition of radioprotectors is an urgent need for the nation. However, the applicability of radioprotectors currently under investigation is limited due to their inherent toxicity. OBJECTIVE This study investigated the effect of a standardized North American ginseng extract (NAGE, total ginsenoside content: 11.7%) on DNA damage in human lymphocytes at 90 minutes postirradiation. DESIGN With the application of NAGE (250-1000 microg mL(-1)) at 90 minutes postirradiation (1 and 2 Gy), DNA damage in lymphocytes obtained from 40 healthy individuals was evaluated by cytokinesis-block micronucleus assay. Similar experiments were also performed in lymphocytes treated with WR-1065 (1 mmol/L or 3 mmol/L). In addition, before and after irradiation, lymphocytes obtained from 10 individuals were measured for their total antioxidant capacity (TAC) and the reactive oxygen species (ROS). RESULTS The significant effect of NAGE against (137)Cs-induced micronuclei (MN) in lymphocytes is concentration dependent. NAGE (750 microg mL(-1)) reduced MN yield by 50.7% after 1 Gy and 35.9% after 2 Gy exposures, respectively; these results were comparable to that of WR-1065. Furthermore, we also found that NAGE reduces MN yield and ROS but increases TAC in lymphocytes. CONCLUSIONS Our results suggest that NAGE is a relatively nontoxic natural compound that holds radioprotective potential in human lymphocytes even when applied at 90 minutes postirradiation. One of the radioprotective mechanisms may be mediated through the scavenging of free radicals and enhancement of the intracellular TAC.


Mutation Research-genetic Toxicology and Environmental Mutagenesis | 2000

Micronuclei in lymphocytes of prostate cancer patients undergoing radiation therapy

Tung Kwang Lee; Kevin F. O'Brien; James Naves; Karen I Christie; Hyder Husain Arastu; Gregory S. Eaves; Albert L. Wiley; Ulf Karlsson; Mohammad Salehpour

To further verify the applicability of the micronucleus (MN) assay in biodosimetry, we measured the MN yield in cytokinesis-blocked (CB) peripheral blood lymphocytes (PBL) of eight prostate cancer (PC) patients. These patients had no previous chemotherapy or radiotherapy (xRT). They were treated with standardized schemes of fractionated pelvic xRT. Before xRT, and at one random time-point during the course of xRT, blood samples were collected from each patient for the following purposes: (1) to verify the relationship between the MN yield in PBL and the estimated equivalent (EQ) total-body absorbed dose; and (2) to evaluate the individual differences of ex vivo radiation dose-response (1-4 Gy) relationship of MN yield in PBL before xRT. The number of xRT fractions, cumulative tumor dose, and EQ total-body absorbed doses of these patients represented a wide range. We found in PBL of these patients that (1) MN yield (Y) increased linearly with the estimated EQ total-body absorbed dose as Y=14.6+9.2D (R(2)=0.7, p=0.007); the distributions of MN yield were overdispersed; the ratio of relative increment of MN yield per 1000 binucleated (BN) PBL ranged from 0.9 to 8.2 (median: 4.1) folds above that of the respective baseline levels; and (2) before xRT, the MN yields also increased linearly with the ex vivo radiation dose; at each radiation dose level, the distributions of MN yield were overdispersed in most patients. In two of the three patients with xRT-induced early side effects (cystitis, diarrhea), the MN yield in PBL induced by ex vivo irradiation before xRT was significantly higher than in the other patients without xRT-induced side effects. These findings suggest that MN yields in CB PBL can be used as an in vivo biodosimeter. Since the differences in individual ex vivo radiation dose-response relationship of MN yield in PBL before xRT appeared to be significant, our preliminary results also suggest that it may be possible to identify individual intrinsic radiosensitivity before the start of xRT.


Cancer | 1986

Cytologic results of fine-needle aspiration biopsies of the central nervous system

Jan F. Silverman; Robert L. Timmons; John R. Leonard; Ira M. Hardy; Lawrence S. Harris; Kevin F. O'Brien; H. Thomas Norris

The cytologic results of 34 fine‐needle aspiration (FNA) biopsies of the central nervous system (CNS) are reported. There were 31 intraoperative biopsies performed at the time of craniotomy All the cases were diagnosed using direct smear preparations stained with Papanicolaou and Diff‐Quik (Harleco, NJ) stains. The sensitivity of the procedure was 90.7%, specificity 100%, positive predictive value 100%, and efficiency of the test of 91%. There were no false‐positive diagnoses and three false‐negative diagnoses. This study attests to the diagnostic accuracy of FNA cytologic examination of the central nervous system. Statistical analysis of the few previous FNA biopsy series of the CNS are presented. Review of the indications, advantages and complications of CNS needle biopsy are discussed. This report supports the role of fine‐needle aspiration cytology in the evaluation of CNS lesions. With recent developments in radiologic imaging, especially ultrasound and computed tomography (CT) using stereotactic guidance, specimens can be obtained for cytologic diagnosis using thinner needles. Excellent diagnostic accuracy can be obtained, as pathologists gain greater familiarity with interpreting FNA biopsy material. Other advantages of FNA biopsy of the central nervous system include the low morbidity and mortality of the procedure and the ability to perform the biopsy through a burr hole under local anesthesia and thereby decrease hospitalization time and cost. Cancer 58:1117‐1121, 1986.


Mutation Research-genetic Toxicology and Environmental Mutagenesis | 1999

Effect of blood storage on radiation-induced micronuclei in human lymphocytes

Tung-Kwang Lee; Kevin F. O'Brien; Gregory S. Eaves; Karen I Christie; Linda Varga

To evaluate the effect of blood storage on the yield of micronuclei (MN) in both irradiated (in vivo and ex vivo) and unirradiated peripheral blood lymphocytes (PBL), we applied the MN assay in cytokinesis-blocked (CB) PBL obtained from healthy subjects (n=11), and from cancer patients (n=10) who were undergoing fractionated partial-body radiotherapy (xRT). The heparinized blood samples were exposed to 137Cs-irradiation (0 Gy or 2 Gy) immediately after blood collection and were stored upright in test tubes either at room temperature (22 degrees C) or in the refrigerator (5 degrees C). Duplicate whole blood cultures from each sample were set up at 0 h, 96 h, and 120 h after ex vivo irradiation. Giemsa (10%) stained slides were prepared from each culture. MN yield was determined per 1000 binucleated cells. As compared to that obtained from the corresponding fresh blood samples, we found that (1) the 22 degrees C blood storage temperature did not affect MN yields in PBL of either healthy subjects or cancer patients up to 96 h, either with or without ex vivo irradiation; and (2) while blood samples were stored at 5 degrees C, the MN yield increased significantly in PBL of healthy subjects (with or without ex vivo irradiation) at 120 h, and in cancer patients (with ex vivo irradiation) at 96 h and 120 h. Since handling of the blood sample is important for CBMN assay during shipment or in the laboratory, our findings showed that blood storage at 22 degrees C or at 5 degrees C up to 96 h appeared to provide insignificant variations of the MN results as compared to fresh blood samples. However, the 96 h of blood storage at 5 degrees C elevated the MN frequency in ex vivo irradiated PBL of cancer patients who were undergoing xRT.


Substance Use & Misuse | 1987

Prevalence of smokeless tobacco use in Pitt County, North Carolina.

Elbert D. Glover; Kevin F. O'Brien; Donald Holbert

The purpose of this study was to estimate the prevalence of smokeless tobacco use in the largest tobacco-producing county in the United States. A 1-in-100 systematic random telephone sample was taken from the county telephone directory. A total of 280 complete questionnaires were obtained. Results indicate that .40 +/- .042 [p +/- SE(p)] males and .09 +/- .024 of females use smokeless tobacco. The point prevalence for the total population was estimated to be .15.


Medicine and Science in Sports and Exercise | 1988

Hydrostatic weighing without head submersion: description of a method

Joseph E. Donnelly; Thomas E. Brown; R. G. Israel; Stephanie Smith-sintek; Kevin F. O'Brien; Bret Caslavka

Hydrostatic weighing (HW) was performed at residual volume (RV) and total lung capacity without head submersion (TLCNS). Ninety-five males (25.6 +/- 4.9 yr) and 87 females (22.6 +/- 5.2 yr) were studied at two laboratory sites using identical protocols. Twenty males and 20 females were separated from the original group and randomly assigned to cross-validation groups. RVs were determined by the oxygen dilution method. Vital capacity was determined with the subject submerged in water to the shoulders. Underwater weight was determined using 10 trials at RV and 5 trials at TLCNS, with the order of methods randomly assigned. Regression analysis provided an equation to predict body density (pDb) at RV from body density (Db) at TLCNS. The equation for males was pDb (HW at RV) = 0.5829 (DbHW at TLCNS) + 0.4059, r = 0.88, SEE = 0.0067. The equation for females was pDb (HW at RV) = 0.4745 (DbHW at TLCNS) + 0.5173, r = 0.85, SEE = 0.0061. Cross-validation showed no significant differences using Db from HW at RV (males = 1.0626 g.ml-1, females = 1.0493 g.ml-1 and pDb from HW at TLCNS (males = 1.0625 g.ml-1, females = 1.0479 g.ml-1). The correlation coefficient SEE and total error for males were r = 0.95, 0.0043, and 0.0041, respectively and for females r = 0.82, 0.0084, and 0.0085, respectively. Mean percent fat for RV and TLCNS was identical for males and differed by 0.7% for females. Test-re-test data indicated the TLCNS procedure was reliable (r = 0.98).(ABSTRACT TRUNCATED AT 250 WORDS)


Neuropsychologia | 1994

Gender differences in laterality patterns for speaking and singing

Monica Strauss Hough; Hal J. Daniel; Michel A. Snow; Kevin F. O'Brien; W.Garrett Hume

This study examined behaviors reflecting cerebral organization of speaking and singing in normal college students. The investigation focused on whether differences existed in the laterality patterns of two singing tasks and one speaking task in males and females. Performance was measured on a verbal/manual time-sharing paradigm, coupling finger tapping with three vocal tasks (speaking, singing a rote song, singing up and down a diatonic five note scale). Females exhibited less variation than males in mean tapping rates and laterality scores across all three vocal tasks, thus indicating that gender most likely influences lateralization of vocal tasks. Bilateral integration was indicated for both males and females during singing up/down the aforementioned scale. These findings suggest differential involvement of both hemispheres in processing musical functions.


Medicine and Science in Sports and Exercise | 1990

Trend analysis for repeated measures designs

Donald Holbert; Thomas C. Chenier; Kevin F. O'Brien

This paper outlines a method of analysis that is well-suited to repeated measures designs. This method uses polynomial functions of time to characterize an outcome variable measured at several distinct time points on the same subjects. Profiles for different treatment groups may be compared using the appropriate interaction terms in an analysis of variance table. The method is illustrated with data from two recent studies.


The Open Nuclear Medicine Journal | 2009

American Ginseng Modifies 137Cs-Induced DNA Damage and Oxidative Stress in Human Lymphocytes

Tung-Kwang Lee; Kevin F. O'Brien; Weidong Wang; Chao Sheng; Tao Wang; Roberta M. Johnke; Ron R. Allison

The multifold bioactive medicinal properties of ginseng have been closely linked to its antioxidative ability, which is related to its ginsenoside content. Since the key mechanism of radiation-induced cell death and tissue damage is the generation of reactive oxygen species (ROS) that attack cellular DNA, this study focuses on the impact of a standardized North American ginseng extract (NAGE) on (137)Cs-induced oxidative stress in human peripheral lymphocytes (PBL) obtained from 10 healthy individuals (6M/4F), 42.7 +/- 4.6 years of age. At two different time points (0 h and 24 h before irradiation), we applied NAGE (250 - 1000 microg ml(-1)) to mononuclear cell cultures for cytokinesis-block micronuclei (MN) assay and determination of the state of oxidative stress in PBL. We found that at both time points, NAGE significantly reduced the MN yields in PBL after irradiation (1 and 2 Gy) in a concentration-dependent manner (P<0.001). Compared with radiation alone, the maximum reduction rate of MN yield were 51.1% and 49.1% after 1 Gy and 2 Gy exposures, respectively. We also found that before irradiation the presence of NAGE in the culture medium resulted in a significant increased intracellular total antioxidant capacity (TAC) in PBL. At both time points, the increment of (137)Cs-induced MN yields in PBL was positively correlated with the increment of intracellular ROS production (R = 0.6 - 0.7, P = 0.002), but negatively correlated with the reduction of TAC levels (R = -0.4 -0.5, P = 0.02 - 0.004). However, the presence of NAGE in the culture medium significantly increased the TAC levels, while concomitantly decreasing both ROS production and MN yields in PBL (P<0.001). Our findings that NAGE is effective in protecting human PBL against radiation-induced oxidative stress should encourage further in vivo study of dietary supplementation with NAGE as an effective natural radiation countermeasure.

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R. G. Israel

East Carolina University

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Tung-Kwang Lee

East Carolina University

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Ron R. Allison

East Carolina University

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Tao Wang

East Carolina University

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Weidong Wang

East Carolina University

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Chao Sheng

East Carolina University

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