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Biomedical subjects

R Bachman

Publications and source records attributed to R Bachman.

At least 19 recordsLinked to original sources
PubMed2006

Atmospheric deposition inputs and effects on lichen chemistry and indicator species in the Columbia River Gorge, USA.

Topographic and meteorological conditions make the Columbia River Gorge (CRG) an 'exhaust pipe' for air pollutants generated by the Portland-Vancouver metropolis and Columbia Basin. We sampled fog, bulk precipitation, throughfall, airborne particulates, lichen thalli, and nitrophytic lichen distribution. Throughfall N and S deposition were high, 11.5-25.4 and 3.4-6.7 kg ha(-1) over 4.5 months at all 9 and 4/9 sites, respectively. Deposition and lichen thallus N were highest at eastern- and western-most sites, implicating both agricultural and urban sources. Fog and precipitation pH were frequently as low as 3.7-5.0. Peak NO(x), NH(3), and SO(2) concentrations in the eastern CRG were low, suggesting enhanced N and S inputs were largely from particulate deposition. Lichens indicating nitrogen-enriched environments were abundant and lichen N and S concentrations were 2x higher in the CRG than surrounding national forests. The atmospheric deposition levels detected likely threaten Gorge ecosystems and cultural resources.

Air Pollutants↗
PubMed2001

A5814G mutation in mitochondrial DNA can cause mitochondrial myopathy and cardiomyopathy.

We describe a 5-year-old child with hypertrophic cardiomyopathy, mitochondrial myopathy, and lactic acidosis. Mitochondrial DNA analysis showed a heteroplasmic A5814G point mutation in the tRNA(Cys) gene. The mutational load was extremely high (>95%) in muscle, fibroblasts, and blood. This report expands the clinical heterogeneity of the A5814G mutation, which should be considered in the differential diagnosis of hypertrophic cardiomyopathy in childhood.

Acidosis, Lactic↗
PubMed1998

Partial trisomy of chromosome 6q: an interstitial duplication of the long arm.

We report on a 5-year-old girl with a de novo interstitial duplication of chromosome 6q21-q23 and delayed development and speech with distinctive minor facial anomalies including a "carp" mouth. Fluorescence in situ hybridization using a chromosome 6 paint probe confirms that the extra material is of chromosome 6 origin. This further delineates the dup(6q) syndrome and the manifestations due to the specific duplicated chromosomal region involved.

Abnormalities, Multiple↗
PubMed1998

Risk of house staff tuberculin skin test conversion in an area with a high incidence of tuberculosis.

We prospectively evaluated rates of tuberculin skin test (TST) conversion from July 1992 to June 1997 among house staff in the Emory University Affiliated Hospitals Training Program following implementation of expanded infection control measures for tuberculosis at Grady Memorial Hospital (Atlanta), which cares for approximately 200 patients with tuberculosis per year. Over 5 years, documented TST conversions occurred for 52 (2.4%) of 2,144 house staff. Conversion rates decreased after the first 6 months from 5.98 to 1.09 per 100 person-years worked over the next 4.5 years (P < .001). Multivariate analysis revealed that risk factors for TST conversion included graduation from a foreign medical school and being part of the house staff in the Department of Medicine; race or ethnicity, gender, and age were not risk factors. Over the last 4.5 years, the TST conversion rate among U.S. medical school graduate house staff (n = 1,928) was 0.72 per 100 person-years worked, and there was no significant difference in conversion rates between house staff in the Department of Medicine and house staff in other departments. In summary, TST seroconversion rates decreased significantly following full implementation of expanded infection control measures for tuberculosis and were low (< 1% per year) among U.S. medical school graduates despite their caring for large numbers of patients with tuberculosis at an inner-city public hospital.

Female↗
PubMed1997

The relationship of alcohol to injury in assault cases.

Little is known about the precise role of alcohol in the escalation of interactions from threats into physical violence or its contribution to the risk of injury. Experimental studies indicate that intoxicated subjects (allegedly) give markedly higher electric shocks than sober subjects and are less sensitive to their cries of pain. However, few studies in a naturalistic setting have examined whether aggressive acts become more serious and result in higher injury rates when the assailants have been drinking than when they are sober. This chapter reviews the two bodies of research on the effects of alcohol on interpersonal aggression and violence; presents new data on the escalation of threatening interactions to assaults and the likelihood of victim injury given an assault, using data from the National Crime Victimization Survey for the years 1992 and 1993; and suggests future directions for research based on our findings that alcohol's impact on both escalation and injury differed according to the victim-assailant relationship.

Adolescent↗
PubMed1997

Predicting the fear of assault at school and while going to and from school in an adolescent population.

Recent research investigating the fear of crime has shown that when crime and behavior-specific measures of fear are utilized, the young are more likely than the elderly to be the most fearful. Research investigating the etiology of fear within adolescent populations, however, remains very limited. Using a sample of over 10,000 junior high and high school students from a supplement to the National Crime Victimization Survey, this paper examines the factors contributing to students' fear of assault both at school and while going to and from school. Results indicate that recent victimization experiences, the presence of a violent subculture at the school (e.g., gang presence and attacks on teachers) and availability of drugs/alcohol were related to fear in both contexts. The predictability of fear from individual characteristics, however, was context specific. Contrary to findings from earlier research, it was found that young females were not more fearful than their male counterparts in all contexts. While they were more fearful of an attack while going to and from school, there were no differences in fear levels while at school between males and females after controlling for other environmental and experiential factors. Conclusions largely support the contention that fear is a rational calculation based on objective criteria. Moreover, results underscore the need for more specificity when operationalizing the context and content of fearfulness.

Adolescent↗
PubMed1995

Police involvement in domestic violence: the interactive effects of victim injury, offender's history of violence, and race.

While there is a proliferation of research devoted to ascertaining the efficacy of arrest and other formal sanctions in deterring domestic violence, little research has focused on factors related to the pivotal point at which this formal sanctioning process begins, namely, in a victim's decision to report her victimization to police. This paper is an attempt to rectify this omission by examining those factors most important in predicting the police-reporting behavior of 1535 female victims of intimate-perpetrated violence (e.g., by husbands and boyfriends) taken from the National Crime Victimization Survey during 1987-1992. In addition to predicting the reporting decision of these victims, models predicting various police responses to a victim's report were also examined, including police response times, police actions at the scene, and the probability of an arrest being made. A combination of contextual and demographic characteristics affected the probability that incidents would be placed into the realm of formal sanctioning. Black victims, victims who sustained injury as the result of their victimization, and victims who reported that the offender had not victimized them before were more likely to report their victimization to police. These same factors were also significant predictors of arrest. Police were more likely to make an arrest in incidents in which victims had sustained injuries, when the offender did not have a history of violence, and in incidents which involved Black offenders victimizing Black victims. Implications for the "Battered Women Syndrome" and suggestions for future research are discussed.

Black or African American↗
PubMed1994

Identification of middle ear effusion by aural acoustic admittance and otoscopy.

The ability of aural acoustic immittance measures and validated pneumatic otoscopy to identify middle ear effusion (MEE) was determined for a group of children with chronic or recurrent otitis media. The measures were made immediately prior to surgery for placement of tympanostomy tubes, with the validating diagnosis of MEE made by the surgeons. Aural acoustic admittance measures were made by a certified and licensed clinical audiologist using an instrument that meets current standards and otoscopic examinations were made by a nurse practitioner validated for use of otoscopy in the identification of MEE. Logistic regression analyses were done to determine the ability of admittance variables, otoscopy, and their combination to discriminate between ears with and ears without MEE. Of the individual admittance variables, tympanometric width had the best performance. Otoscopy alone had good sensitivity but only fair specificity. Combining acoustic admittance data with the otoscopist's findings did not improve sensitivity greatly, but improved the specificity relative to that of the otoscopist. The criterion tympanometric width > 150 daPa or Ytm < 0.2, a criterion commonly used based on interim norms published in an appendix of ASHA guidelines for screening, had good sensitivity but very poor specificity in the group of children scheduled for surgery. Also, a comparison was made for tympanometric width measures from the children undergoing surgery with those from a group of children more representative of the general population. Three distributions were found; one for ears with MEE, one for ears with no MEE of children scheduled for otologic surgery and one for ears with no MEE from the group of children from the general population. The data illustrate the importance of the population characteristics on the test measure used and have implications for choosing test criteria. In addition, group estimates of performance of acoustic admittance variables were approximately the same when otoscopy was used as the gold standard for identification of MEE as when findings at surgery were used. However, when comparing the two diagnostic methods on a case-by-case basis, it was determined that the otoscopist's diagnosis disagreed with the diagnosis of the surgeons in over 21% of the ears.

Acoustic Impedance Tests↗
PubMed1992

Towards the validation of aural acoustic immittance measures for diagnosis of middle ear effusion in children.

Acoustic admittance testing was done on the ears of two groups of children. The first group was comprised of children undergoing myringotomy and tube surgery for treatment of chronic or recurrent otitis media, and the second group was comprised of hospital outpatients who were unscreened with respect to a history of middle ear disease and who were more representative of children in the general population. The admittance measures were then analyzed with respect to middle ear status (effusion versus no effusion) as determined by the surgeon (surgery group) and by validated otoscopy (outpatient group). Based on the data from the surgery group, the best admittance criteria for the identification of middle ear effusion were determined and then tested with respect to the data from subjects in the outpatient group. Sensitivity and specificity of several different criteria were similar. The role of prevalence of disease and the value of admittance measures such as gradient and acoustic reflex are discussed in the context of diagnostic testing in clinical or research protocols as well as in the context of immittance screening programs.

Acoustic Impedance Tests↗
PubMed1989

Emergency medical care requirements for large public assemblies and a new strategy for managing cardiac arrest in this setting.

During the 1986 World's Exposition held in Vancouver, British Columbia, the types and frequencies of emergency medical problems were assessed. The average number of patients seeking care was 3.93 +/- 0.95 per 1,000 visitors (daily range, 1.94 to 6.8). Patient loads were linearly related to gate attendance, but the correlation was imperfect (P less than .001, r = .63). Only 4.4% of patients evaluated on site by nurses and paramedics were referred for additional testing and treatment: of these patients, 30% had suspected serious musculoskeletal injury, 16% had abdominal pain, and 25% had complaints of chest pain, dizziness, or loss of consciousness. Lay employees (security personnel) were trained to use automatic external defibrillators. There were six cardiac arrests (0.3 per million visitors). Two patients collapsed with ventricular fibrillation, were defibrillated by lay personnel, quickly regained consciousness, and survived. The other arrests were associated with asystole or electromechanical dissociation; no shocks were inappropriately given, and all four died. We conclude that four of every 1,000 persons at this assembly sought emergency medical care, that 95% of the problems seen were minor with few requiring physician skills, and that the automatic external defibrillator was suited for this setting and could be used by lay responders to provide early definitive treatment.

Adolescent↗
PubMed1985

Chromosomal abnormalities in the Kaiser-Permanente Birth Defects Study, with special reference to contraceptive use around the time of conception.

Chromosomal abnormalities were studied in 33,551 abortions and births to women whose contraceptive histories had been recorded at their first antenatal visit in 1975-1977. Chromosome examinations were performed exclusively on clinical grounds. There were 45 de novo abnormalities detected (1.34/1,000); three of them were detected at amniocentesis. Trisomy 21 was observed in 27 cases (0.80/1,000), trisomy 18 in nine (0.27), other trisomies in three (0.09), and translocations or deletions in five (0.15). One case of triploidy and six cases of inherited abnormalities were detected. There were no significant racial variations. No increase in risk for chromosomal abnormalities was found among women who had used oral contraceptives prior to becoming pregnant or among women who experienced oral contraceptive breakthrough pregnancies. Two cases of trisomy 18 were observed among the 814 deliveries following oral contraceptive breakthrough conceptions (2.46/1,000), two cases of trisomy 21 occurred in 338 births following failures of rhythm contraception (5.92/1,000), and no cases of trisomy 21 or 18 among the 1,569 women using spermicides at the time of conception.

Abnormalities, Drug-Induced↗
PubMed1983

The Pena-Shokeir syndrome: report of five cases and further delineation of the syndrome.

We report on five cases of lethal Pena-Shokeir syndrome from three families with affected sibs. In addition to multiple anklyoses, camptodactyly, facial anomalies, and pulmonary hypoplasia, one fetus had pterygia of the neck and axillae and cardiac hypoplasia. Radiographic changes are nonspecific and probably are related to a lack of intrauterine movement. Our data and review of the literature suggest that pterygium formation is one of the manifestations of the Pena-Shokeir syndrome. A recently described lethal form of the recessively inherited multiple pterygium syndrome may represent a severe form of the Pena-Shokeir syndrome.

Abnormalities, Multiple↗
PubMed1977

Partial trisomy 10p and familial translocation t(7;10)(p22;p12).

A girl with partial trisomy for the short arm of chromosome 10(p12leads to pter) due to mal chromosome segregation in the father 46,XY,t(7;10)(p22;p12) is described. The major abnormalities in this case are: mottled skin, mid-facial hypoplasia, low percentiles for weight, length, and head circumference, and club feet.

Abnormalities, Multiple↗
PubMed1976

A 46,XY, del(18)(pter leads to p1 100:) cebocephalic child from a 46,XX,t(12;18)(18pter leads to 18 p 1100:: 12qter leads to 12pter) normal parent.

A normal female with an 18p--chromosome but without any feature of the 18p--syndrome produced a cebocephalic child whose karyotype included an 18p--chromosome. Evidence is presented that the normal female is a nonreciprocal translocation heterozygote resulting from the short arm of one chromosome 18 becoming attached to the long arm of a chromosome 12.

Abnormalities, Multiple↗
PubMed1976

Tetraploidy in a liveborn infant.

A congenitally malformed infant with a tetraploid chromosome complement who survived to 1 year of age is reported. The relationship of the polyploidy and the anomalies is discussed.

Abnormalities, Multiple↗