PubMed Health⌕ Search

Biomedical subjects

G C Gray

Publications and source records attributed to G C Gray.

At least 37 records · Page 2Linked to original sources
PubMed1999

The postwar hospitalization experience of Gulf War Veterans possibly exposed to chemical munitions destruction at Khamisiyah, Iraq.

Using Department of Defense hospital data, the authors examined the postwar hospitalization experience from March 1991 through September 1995 of US Gulf War veterans who were near Khamisiyah, Iraq, during nerve agent munition destruction in March 1991. Multiple sources of meteorologic, munition, and toxicology data were used to circumscribe geographic areas of low level, vaporized nerve agent for 4 days after the destruction. Plume estimates were overlaid on military unit positions, and exposure was estimated for the 349,291 US Army Gulf War veterans. Exposure was classified as not exposed (n = 224,804), uncertain low dose exposure (n = 75,717), and specific estimated subclinical exposure (n = 48,770) categorized into three groups for dose-response evaluation. Using Cox proportional hazard modeling, the authors compared the postwar experiences of these exposure groups for hospitalization due to any cause, for diagnoses in 15 unique categories, and for specific diagnoses an expert panel proposed as most likely to reflect latent disease from such subclinical exposure. There was little evidence that veterans possibly exposed to the nerve agent plumes experienced unusual postwar morbidity. While there were several differences in hospitalization risk, none of the models suggested a dose-response relation or neurologic sequelae. These data, having a number of limitations, do not support the hypothesis that Gulf War veterans are suffering postwar morbidity from subclinical nerve agent exposure.

Adolescent↗
PubMed1999

Risk factors for mental disorder hospitalization after the Persian Gulf War: U.S. Armed Forces, June 1, 1991-September 30, 1993.

Effects of Persian Gulf War (August 2, 1990-July 31, 1991) and Gulf War occupation on post-War hospitalization risk were evaluated through Cox proportional hazards modeling. Active-duty men (n = 1,775,236) and women (n = 209,760) in the Army, Air Force, Navy, and Marine Corps had 30,539 initial postwar hospitalizations for mental disorders between June 1, 1991 and September 30, 1993. Principal diagnoses in the Defense Manpower Data Center hospitalization database were grouped into 10 categories of ICD-9-CM codes. Gulf War service was associated with significantly greater risk for acute reactions to stress and lower risk for personality disorders and adjustment reactions among men. Personnel who served in ground war support occupations (men and women) were at greater risk for postwar drug-related disorders. Men who served in ground war combat occupations were at higher risk for alcohol-related disorders. Longitudinal studies of health, hospitalization, and exposure beginning at recruitment, are needed to better understand how exposure to combat affects the mental health of military personnel.

Adolescent↗
PubMed1999

Remote village survey for agents causing hepatosplenic disease in the Republic of Yemen.

The objective of this study was to epidemiologically describe potential infectious agents among rural people in the Republic of Yemen. This would aid clinicians in designing empirical therapy and public health officials in planning disease prevention. We sought to examine evidence for the geographical distribution of pathogens causing human hepatic and splenic disease among villagers and domestic animals living in three remote areas with differing altitudes. In June 1992, a cross-sectional survey was conducted at three survey sites of differing altitudes: 3080, 1440 and 250 m above sea level. Questionnaires, parasitic and serological tests were administered to 627 human volunteers. Additionally 317 domestic animals were studied. Malaria, schistosomiasis, and hepatitis B and C infections were found to be likely causes of human hepatic or splenic disease. Additionally, evidence of human and animal infections with the agents of brucellosis and Q fever was found: IgG antibodies against hepatitis E virus were discovered in two (2.0%) of the 100 volunteers. The prevalence of markers for human and animal disease was often lowest at the village of highest elevation, suggesting that increasing altitude, as a surrogate or a true independent risk factor, was protective against infection with the agents studied.

Adolescent↗
PubMed1999

No serologic evidence of an association found between Gulf War service and Mycoplasma fermentans infection.

Occult occupational infection with Mycoplasma fermentans has been proposed as a cause for illness among Persian Gulf War veterans. Symptom data and sera from a 1994-1995 cross-sectional survey of Navy Seabees were used to select symptomatic and asymptomatic Gulf War veterans and nondeployed veterans to evaluate this hypothesis. Survey sera from 96 Seabees were matched to prewar (before September 1990) archived sera. Immunoblot serologic analyses were performed for M. fermentans in a controlled, blinded fashion. Both Gulf War veterans and nondeployed veterans had prewar and postwar serologic evidence of M. fermentans infection consistent with natural infection data. Among study subjects collectively, and stratified by Gulf War service, none of the immunoblot banding profiles (prewar or postwar) or their changes over time were associated with postwar symptoms. These serologic data do not support the hypothesis that Gulf War veterans have experienced Gulf War-related morbidity from M. fermentans infection.

Adult↗
PubMed1999

Increased postwar symptoms and psychological morbidity among U.S. Navy Gulf War veterans.

To investigate reports on war-related morbidity, 527 active-duty Gulf War veterans and 970 nondeployed veterans from 14 Seabee commands were studied in 1994 with a questionnaire, sera collection, handgrip strength, and pulmonary function testing. The questionnaire assessed postwar symptoms, war exposures, and screened for chronic fatigue syndrome, post-traumatic stress disorder, and psychological symptoms suggesting neurosis (Hopkins Symptom Checklist). Sera were tested with four nonspecific reactant assays: C-reactive protein, transferrin, ferritin, and haptoglobin. Gulf War veterans reported a higher prevalence for 35 of 41 symptoms, scored higher on psychological symptom scales, were more likely to screen for post-traumatic stress disorder, had lower handgrip strength, and had higher serum ferritin assay results. Numerous comparisons of these morbidity outcomes with 30 self-reported exposures demonstrated many associations, but no unique exposure or group of exposures were implicated. Morbidity data are consistent with other postwar observations, but the etiology for morbidity findings remains uncertain.

Adult↗
PubMed1998

Gulf War Veterans' Health Registries. Who is most likely to seek evaluation?

Since the Persian Gulf War ended in 1991, many veterans have sought medical evaluation in the Department of Veterans Affairs Persian Gulf Veterans' Health Registry (VA registry) or the Department of Defense's Comprehensive Clinical Evaluation Program (DoD registry). Using combined data collected from 1993 to 1997 from the VA and DoD registries, the authors compared the characteristics of registry participants (n=74,653) with those of all Gulf War veterans (n=696,531) to determine the personnel most likely to seek medical evaluation. Using multiple logistic regression, the authors found that service branch and type were strongly associated with registry participation, with Army (adjusted odds ratio (OR)=4.7, 95% confidence interval (CI) 4.6-4.9) and National Guard (OR=2.6, 95% CI 2.5-2.6) personnel at highest odds compared with reference category personnel. Registry participants also were more likely to have been stationed in the Gulf War theater during the fighting (OR=2.2), to be older (>31 years/<22 years OR=2.1), to have been an enlisted person (OR=2.0), to have been construction workers (OR=1.3), to be female (OR=1.3), and to have been hospitalized during the 12-month period before the war (OR=1.2). These findings are useful in generating hypotheses regarding postwar morbidity. They also suggest that subpopulations of Gulf War veterans have a higher prevalence of symptoms and merit further study.

Adult↗
PubMed1998

Peroxidation of membrane lipids and oxidative DNA damage by fumonisin B1 in isolated rat liver nuclei.

Fumonisin B1 (FB1), a contaminant of corn, has been reported to be a hepatocarcinogen in rats. In an attempt to understand its mechanisms of action, a model system of isolated rat liver nuclei was used to determine what effects, if any, FB1 might have on nuclear membrane lipids and DNA. The data suggested that FB1 induced lipid peroxidation concurrently with DNA strand breaks in this in vitro system. Iron and copper had no statistically significant stimulatory effects on these reactions. In addition, the active oxygen scavengers catalase, superoxide dismutase (SOD), mannitol and sodium azide had no significant inhibitory effects on the FB1-induced DNA strand breaks. However, a small but significant reduction in lipid peroxidation by catalase and mannitol was observed. These results suggested that hydroxyl radicals may be the initiators of the nuclear membrane lipid peroxidation, which results in production of peroxyl radicals. In turn, the peroxyl radicals may be responsible for the DNA strand breaks. An alternative explanation is that the hydroxyl radicals, produced close to the DNA-bound metal ions, may induce direct site-specific strand breaks, which are insensitive to the scavengers of active oxygen.

Animals↗
PubMed1998

Weekly oral azithromycin as prophylaxis for agents causing acute respiratory disease.

Since the 1950s the U.S. military has used intramuscular injections of benzathine penicillin G (BPG) to control outbreaks of respiratory disease. In an effort to find an alternative prophylaxis, a randomized field trial was conducted among 1,016 male U.S. Marine trainee volunteers at high risk for respiratory disease. Participants were evaluated for evidence of acute respiratory infection by serological tests on pretraining and posttraining sera (63 days apart). Oral azithromycin prophylaxis (500 mg/w) outperformed BPG, preventing infection from Streptococcus pyogenes (Efficacy [E] = 84%; 95% confidence interval [CI], 63%-93%), Streptococcus pneumoniae (E = 80%; 95% CI, 50%-92%), Mycoplasma pneumoniae (E = 64%; 95% CI, 25%-83%), and Chlamydia pneumoniae (E = 58%; 95% CI, 15%-79%) in comparison with results in a no-treatment group. Azithromycin group subjects reported few side effects and less respiratory symptoms than the BPG and no-treatment groups. According to serological tests, oral azithromycin is an effective alternative prophylaxis to BPG for military populations.

Administration, Oral↗
PubMed1998

Risk factors for primary pulmonary coccidioidomycosis hospitalizations among United States Navy and Marine Corps personnel, 1981-1994.

Recent coccidioidomycosis outbreaks among military personnel have alarmed public health officials. We used computerized hospitalization records to identify risk factors for coccidioidomycosis hospitalizations among active-duty United States Navy and Marine Corps personnel for the years 1981 to 1994. Primary pulmonary disease was the most common form of disease, accounting for 82 (73%) of the 113 first admissions. Crude annual rates of primary pulmonary disease increased markedly in 1992 and 1993 in concert with an epidemic in the United States. Demographic data from the pulmonary admissions were combined with that of a 2% random sample of the entire Navy and Marine Corps population for multivariate risk factor modeling. Persons from junior paygrades, older age groups, and those reporting a race/ethnicity other than Caucasian or Hispanic were most likely to be hospitalized with this disease. These risk factor data should be considered in designing coccidioidomycosis surveillance and prevention programs.

Adolescent↗
PubMed1998

Testicular cancer and Persian Gulf War service.

We studied whether regular, active-duty servicemen deployed to the Persian Gulf War were at increased risk of testicular cancer compared with nondeployed Gulf War-era servicemen from August 1991 through March 31, 1996, using a Cox proportional hazards model for survival analysis with covariates. Race was an important predictor of hospitalization for testicular cancer [rate ratio (RR) = 0.19; 95% confidence interval (CI) = 0.12-0.29 for blacks, and RR = 0.59; 95% CI = 0.39-0.91 for Hispanics, other, and unknown (combined), relative to whites]. Age effects were modest (RR = 1.19; 95% CI = 0.91-1.56 for those of ages 22-25 years, and RR = 1.24; 95% CI = 0.96-1.59 for those of ages 26-31 years, compared with those of ages 17-21 years). Risk also varied with occupation (RR = 1.56; 95% CI = 1.23-2.00 for those in electronic equipment repair; RR = 1.26; 95% CI = 1.01-1.58 for those in electrical/mechanical repair; and RR = 1.42; 95% CI = 0.93-2.17 for those in construction-related trades, compared with those in other occupations). Deployment status was not important (RR = 1.05; 95% CI = 0.86-1.29 for the deployed compared with the nondeployed). There was an increase in testicular cancer in the deployed group in the immediate postwar period that was consistent with a previous report of a standardized RR of 2.12; 95% CI = 1.11-4.02 (compared with the nondeployed group) in the last 5 months of 1991, but by 4 years after the end of deployment, the cumulative risks for the two groups were not different. An additional analysis suggested that the immediate postwar increase in the deployed was likely due to regression to the mean after a healthy serviceman selection effect for deployment and the deferment of care during deployment.

Adolescent↗
PubMed1997

The risk of birth defects among children of Persian Gulf War veterans.

BACKGROUND: There has been suspicion that service in the Persian Gulf War affected the health of veterans adversely, and there have been claims of an increased rate of birth defects among the children of those veterans. METHODS: We evaluated the routinely collected data on all live births at 135 military hospitals in 1991, 1992, and 1993. The data base included up to eight diagnoses from the International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) for each birth hospitalization, plus information on the demographic characteristics and service history of the parents. The records of over 75,000 newborns were evaluated for any birth defect (ICD-9-CM codes 740 to 759, plus neoplasms and hereditary diseases) and for birth defects defined as severe on the basis of the specific diagnoses and the criteria of the Centers for Disease Control and Prevention. RESULTS: During the study period, 33,998 infants were born to Gulf War veterans and 41,463 to non-deployed veterans at military hospitals. The overall risk of any birth defect was 7.45 percent, and the risk of severe birth defects was 1.85 percent. These rates are similar to those reported in civilian populations. In the multivariate analysis, there was no significant association for either men or women between service in the Gulf War and the risk of any birth defect or of severe birth defects in their children. CONCLUSIONS: This analysis finds no evidence of an increase in the risk of birth defects among the children of Gulf War veterans.

Adult↗
PubMed1997

Goldenhar syndrome among infants born in military hospitals to Gulf War veterans.

Reports in the popular press described the occurrence of Goldenhar syndrome among children of Persian Gulf War veterans (GWVs). The objective of this investigation was to compare the birth prevalence of Goldenhar syndrome among infants born in military hospitals to GWVs and to military personnel who were not deployed to the Gulf War (NDVs). Computerized hospital discharge data were reviewed for infants conceived after the war and born prior to the 1st of October, 1993, in medical treatment facilities (MTFs) operated by the U.S. Department of Defense. Medical records were evaluated for infants diagnosed at birth with at least one abnormality that might be related to Goldenhar syndrome. Two pediatricians, blinded to the parental Gulf War status of each infant, reviewed records. An estimated 75,414 infants were conceived after the Gulf War and born in MTFs during the study period (34,069 GWV infants and 41,345 NDV infants). Seven infants fulfilled the case criteria (five GWV infants and two NDV infants). All infants had fathers who served in the military at the time of their conception and birth. The birth prevalence was 14.7 per 100,000 live births among GWV infants (95% confidence interval [CI]: 5.4-36.4) and 4.8 per 100,000 live births (95% CI: 0.8-19.5) among NDV infants (relative risk: 3.03; 95% CI: 0.63-20.57; P values: [2-tailed] = 0.26, [1-tailed] = 0.16). The few affected cases and the broad confidence intervals surrounding the relative risk require that these results be interpreted with caution and do not exclude chance as an explanation for these findings.

Adolescent↗
PubMed1997

Lipid peroxidation and DNA damage induced by morin and naringenin in isolated rat liver nuclei.

The pro-oxidant activities, as determined by lipid peroxidation and DNA strand breaks, of morin and naringenin, two polyphenolic flavonoids with molecular structures similar to quercetin, were investigated under aerobic conditions in a model system of isolated rat liver nuclei. Both flavonoids induced a concentration-dependent peroxidation of nuclear membrane lipids concurrent with DNA strand breaks. These reactions were enhanced by the metal ions iron or copper. Active oxygen scavengers catalase, superoxide dismutase and mannitol had no effect on the flavonoid-induced nuclear DNA damage in the presence of the metal ions; nuclear lipid peroxidation was partially inhibited only by mannitol. It appears that hydroxyl radicals are the initiators of the peroxidation of nuclear membrane lipids, producing peroxidation products such as peroxyl radicals that in turn may be responsible for the DNA strand breaks. Alternatively, the hydroxyl radicals produced close to the DNA backbone may induce direct site-specific strand breaks that are insensitive to the free radical scavengers. These results demonstrate the pro-oxidant activities of polyphenolic flavonoids, which are generally considered as antioxidants and anticarcinogens, and suggest their possible dual role in mutagenesis and carcinogenesis.

Animals↗
PubMed1997

Evaluation of pertussis in U.S. Marine Corps trainees.

One hundred twenty male U.S. Marine Corps trainees with histories of at least 7 days of cough underwent evaluation for Bordetella pertussis infection by culture, B. pertussis-specific polymerase chain reaction (PCR) analysis, and serology. Antibody levels in preexposure, acute-phase, and convalescent-phase serum samples were measured in a microagglutination assay and in enzyme linked immunosorbent assays (ELISAs) for IgG and IgA antibodies to pertussis toxin, filamentous hemagglutinin, pertactin, and fimbriae types 2 and 3. Culture and PCR analysis revealed that none of the patients were positive for B. pertussis; however, 20 of 120 trainees had serological evidence of B. pertussis infection. Of these cases, one was confirmed by a rise in the level of antibody to pertussis toxin, and six were classified as probable by increases in levels of antibodies measured by two or more assays. Of the 20 individuals with serological evidence of infection, 16 had rises in levels of antibodies to fimbriae or agglutinating antibodies. The utility of ELISA for detecting antibodies to fimbriae and the microagglutination assay for diagnosing pertussis in adults should be evaluated by application to larger and more diverse study populations. These results indicate that pertussis should be considered in the diagnosis of coughing illness in military populations.

Adhesins, Bacterial↗
PubMed1997

Prediction of relapse after treatment of coccidioidomycosis.

Relapse after apparently successful treatment of coccidioidomycosis has been a problem with both amphotericin B and the azoles. We conducted a retrospective cohort study of 34 patients who required therapy for coccidioidomycosis between 1973 and 1993; 10 relapsed and 25 (one patient received two courses of therapy) did not relapse during follow-up. The mean time to relapse after completion of therapy was 7.3 months (range, 1-21 months). All 34 patients responded clinically to therapy. A fourfold or greater decrease in titers of antibody, as determined by complement fixation (CF), during therapy was seen in seven (78%) of nine patients who relapsed and 17 (85%) of 20 patients who did not relapse (P = .956). There was no significant difference between relapsers and nonrelapsers in terms of the lowest CF titer during therapy, the CF titer at the end of therapy, or the peak CF titer. The risk of relapse was increased among those with a peak CF titer of > or = 1:256 (relative risk [RR] = 4.7; 95% confidence interval [CI] = 1.4-16.1), as compared with patients who did not mount such a high antibody response. Similarly, the risk of relapse was higher among those with serially negative coccidioidin skin tests (CSTs) than those with serially positive CSTs (RR = 4.8; 95% CI = 1.2-19.5). We conclude that clinical response, lowest CF titer, end-of-therapy CF titer, and decrease in the CF titer of at least fourfold are not predictive of relapse in patients with coccidioidomycosis. Negative serial coccidioidin skin tests and a peak CF antibody titer of > or = 1:256 are independently associated with increased risk of relapse.

Adolescent↗
PubMed1997

Mycoplasma pneumoniae: a frequent cause of pneumonia among U.S. Marines in southern California.

From August 1993 through April 1994, U.S. Marines (98% male, median age 20 years) who were hospitalized with radiographically confirmed pneumonia were prospectively studied for evidence of acute Mycoplasma pneumoniae infection. Overall, 32 (36.4%) of the 88 patients with paired sera had evidence of acute infection by an elevated immunoglobulin M titer (22.7%), a 4-fold rise in immunoglobulin G titer (9.1%), a positive polymerase chain reaction result (11.1%), and/or a positive culture (5.8%). No specific symptoms or clinical findings were strong predictors of M. pneumoniae infection. Among patients with evidence of acute M. pneumoniae infection, admitting clinicians chose other pathogens as more likely etiologic agents 46.4% of the time, and over the course of the hospitalization, 10% of patients failed to receive appropriate antibiotics. These data indicate that M. pneumoniae may cause a high proportion of pneumonias among military personnel and should be considered in empiric treatment and prophylaxis.

Acute Disease↗