Genotype × Seeding Rate Interaction among TSWV-Resistant, Runner-Type Peanut Cultivars1

Tomato spotted wilt virus (TSWV) resistant, runner-type peanut (Arachis hypogaea L.) cultivars are the most important defense to control spotted wilt disease in southeast U.S. peanut production. The objective of this 3-yr (1999–01) study was to evaluate six TSWV-resistant, runner-type cultivars (Southern Runner, Florida MDR 98, C-99R, ViruGard, Georgia Green, and Georgia-OIR) at three different seeding rates (3, 5, and 7 seed/30.5 cm) in single conventional row patterns for possible genotype (GE) × seeding rate (SR) interaction at the Univ. of Georgia, Coastal Plain Experiment Station. The combined split-plot analyses of variance resulted in highly significant (P ≤ 0.01) GE × SR interaction, which indicates that not all six runner-type cultivars performed the same at each of these three seeding rates. A good example was the TSWV-resistant, runner-type peanut cultivar Georgia Green. It performed subpar at the below normal or lowest seeding rate; whereas at the highest seeding rate, Georgia Green and Georgia-OIR produced the highest pod yields and dollar value returns per hectare among all of these runner-type cultivars. TSWV disease incidence was also significantly lower for the TSWV-resistant Georgia Green cultivar at each of the two higher seeding rates compared to the lowest seeding rate.

Alcohol as a risk factor for HIV transmission among American Indian and Alaska Native drug users

Quantitative alcohol interviews conducted as part of the National Institute on Drug Abuse (NIDA) Native American Supplement revealed very high rates of alcohol use among American Indian and Alaska Native active crack and injection drug users (IDUs). Of 147 respondents who completed the alcohol questionnaire, 100& percent had drunk alcohol within the past month, almost 42& percent reported that they drank every day, and 50& percent drank until they were drunk one-half of the time or more. Injection drug users (IDUs) demonstrated the highest frequency and quantity of alcohol use in the past 30 days. A significant positive association was also found between crack and alcohol use in the past 48 hours (c(2)=5.30, p<.05). Finally, those claiming more episodes of using alcohol before or during sex, reported significantly more events of unprotected sexual intercourse. Qualitative data from all four sites corroborated these quantitative findings. Many individuals also reported episodes of blacking out while drinking, and learned later that they had had unprotected sex with complete strangers or individuals they would not otherwise accept as partners. Implications of these findings for HIV/AIDS prevention efforts are addressed.

The Atlanta Urban Networks Study: a blueprint for endemic transmission

OBJECTIVE

To study prospectively social networks and behavior in a group of persons at risk for HIV because of their drug-using and sexual practices, with particular emphasis on the interaction of risks and concomitant network structure.

METHODS

A longitudinal study was conducted of 228 respondents in Atlanta, Georgia in six inner-city community chains of connected persons, interviewing primary respondents and a sample of their contacts every 6 months for 2 years. Ascertained were: HIV and immunologic status; demographic, medical, and behavioral factors; and the composition of the social, sexual, and drug-using networks.

RESULTS

The prevalence of HIV in this group was 13.3% and the incidence density was 1.8% per year. Substantial simultaneity of risk-taking was observed, with a high level of both non-injecting (crack, 82%) and injecting (heroin, cocaine or both, 16 30%) drug use, the exchange of sex or money for drugs by men (approximately 35%) and women (57-71%), and high frequency of same-sex sexual activity by men (9.4%) and women (33%). The intensity of interaction, as measured by network features such as microstructures and concurrency, was significantly greater than that observed in a low prevalence area with little endemic transmission.

CONCLUSION

The traditional hierarchical classification of risk for HIV may impede our understanding of transmission dynamics, which, in the setting of an inner-city population, is characterized by simultaneity of risk-taking, and moderately intense network interactions. The study provides further evidence for the relationship of network structure to transmission dynamics, but highlights the difficulties of using network information for prediction of individual seroconversion.

HIV/AIDS risks among Native American drug users: key findings from focus group interviews and implications for intervention strategies

A multisite study funded through the National Institute on Drug Abuse and the Office of Research on Minority Health was conducted in 1996 to determine the HIV/AIDS prevention needs of Native American out-of-treatment drug users. In an effort to recommend directions for HIV/AIDS prevention programming, one component of this study entailed conducting a series of focus groups at each of four sites: Anchorage, Alaska; Denver, Colorado; Flagstaff, Arizona; and Tucson, Arizona. While some site differences were noted, several consistent thematic findings were revealed across all locations. Specifically, focus group members strongly recommended directly involving key members of the Native American community in conducting outreach and intervention activities, involving Native people as the sources of information, and utilizing local and tribally relevant forms of delivering the message. Other consistent themes included getting messages to smaller communities to prevent the potential "annihilation" of tribes, educating youth, and linking alcohol prevention education to HIV/AIDS education. Findings from this study support the idea that future HIV/AIDS prevention programs must take into account subgroup and individual level differences among Native American drug users.

Response of Early, Medium, and Late Maturing Peanut Breeding Lines to Field Epidemics of Tomato Spotted Wilt

Epidemics of tomato spotted wilt, caused by tomato spotted wilt Tospovirus (TSWV), were monitored in field plots of runner-type peanut (Arachis hypogaea L.) cultivars Georgia Green and Georgia Runner and numerous breeding lines from four different breeding programs as part of efforts toward characterizing breeding lines with potential for release as cultivars. Breeding lines were divided into early, medium and late maturity groups. The tests were conducted near Attapulgus, GA and Marianna, FL in 1997 and in Tifton, GA and Marianna, FL in 1998. Epidemics in some early and medium maturing breeding lines, including some genotypes with high oleic acid oil chemistry, were comparable to those in Georgia Green, the cultivar most frequently used in the southeastern U.S. for suppression of spotted wilt epidemics. No early maturing breeding lines had lower spotted wilt final intensity ratings or higher yields than Georgia Green. However, spotted wilt intensity ratings in some late maturing lines and a smaller number of medium maturing lines were significantly lower than those of Georgia Green. Several of those lines also produced greater pod yields than Georgia Green. Results from these experiments indicated that there is potential for improving management of spotted wilt though development of cultivars that suppress spotted wilt epidemics more than currently available cultivars. There was no indication that differences in spotted wilt ratings corresponded to differences in numbers of thrips adults or larvae.

Sex partners of Native American drug users

This study describes patterns of sexual behavior and condom use in a sample of Native American drug-using men and women (N = 114). Data are self-reports of sexual behavior in the last 30 days, including descriptions of the most recent sex partners up to five. These data provided information on 157 sex partner pairs, of which at least one partner was a drug user. Native American women (55%) were more likely than Native American men (23%) to report never using condoms for vaginal and anal sex in the last 30 days. Compared with other ethnic pair combinations, sex partner pairs composed of Native American women and white men (n = 18) were the least likely to use condoms (6% of pairs) and the most likely to report an injection drug user (IDU) sex partner (33% of pairs). These results suggest a potential vector of HIV and other sexually transmitted disease (STD) transmission between white male IDUs and Native American women and highlight the need for further qualitative and quantitative research to examine the factors underlying this pattern of sexual risk behavior.

Developing culturally sensitive HIV/AIDS and substance abuse prevention curricula for Native American youth

In 1990, researchers and health care professionals joined with members of several southwestern Native American communities to form an HIV/AIDS and substance abuse prevention partnership. Culturally sensitive approaches to theory-based interventions were developed into highly replicable, structured, school-based and community-based intervention programs. Process evaluations indicated high levels of program acceptance and fidelity. Outcome evaluations demonstrated significant positive preventive intervention effects among participants. This article reports how NAPPASA school prevention curricula were developed and discusses three critical processes in developing these successful curricula: 1) selection of integrative theory to address the multi-dimensional antecedents of HIV/AIDS and substance abuse among Native Americans, 2) use of ethnographic methodology to obtain intensive input from target groups and community members to ensure cultural and developmental sensitivity in the curriculum, and 3) use of process and outcome evaluations of pilot and field trials to develop an optimal curriculum.

Prenatal toxicity studies in rats and rabbits with the calcium channel blocker diproteverine

In prenatal toxicity studies, diproteverine, a calcium channel blocker with demonstrated antianginal properties, produced an unusual pattern of digital, heart, tail, and vertebral defects in rat fetuses from mothers treated during the major period of organogenesis, but only a very low incidence of heart abnormalities was seen in the rabbit. Heart changes were rarely seen in association with digital defects. The findings were consistent with those seen with other calcium channel blockers and add weight to the suggestion of Danielsson and colleagues (5) that digital malformations are a class effect for this type of compound, the effects being related to reduced uteroplacental blood flow. In addition, it is proposed that cardiovascular malformations are also a class response with calcium channel blockers. The distribution of fetal death and hemorrhages and the varying association between cardiovascular, digital, and tail abnormalities seen in the rat with increasing doses of diproteverine fits the pattern of changes reported following hypoxia in the chick embryo. Reduced uteroplacental blood flow with resultant embryonic hypoxia secondary to pharmacologic action is considered a probable mechanism of action for the induction of abnormalities produced by calcium channel blockers.

Multivariate quantitative structure-toxicity relationships in a series of dopamine mimetics

The techniques of principal components analysis and non-linear mapping are routinely used by computer chemists at SmithKline Beecham Pharmaceuticals in the process of drug development by relating the structure of a compound to its chemical activity. To our knowledge these techniques had not previously been applied to the association between the structure of a compound and its toxicological properties. Using a series of 12 structurally related compounds (11 were active dopamine mimetics and one was inactive), of which five were known to be teratogenic and seven were non-teratogenic, it was possible to demonstrate that molecular modelling techniques could be applied to differentiate toxicological data. The structure/property relationships of these compounds were investigated using calculated physicochemical properties, molecular modelling and multivariate statistical techniques. A data set of 56 molecular descriptors was used to represent this series of compounds. Analysis of the data set using principal components analysis and non-linear mapping suggested that teratogenicity was associated with four molecular properties. Moreover, the electronic nature of the 4-phenyl group appeared to be an important determinant of the teratogenesis.

A qualitative assessment of developmental toxicity within a series of structurally related dopamine mimetics

A qualitative assessment of developmental toxicity within a series of 12 structurally related compounds, 11 of which were active dopamine mimetics and one was inactive, was conducted in rats treated orally by gavage during the major period of organogenesis. Doses were chosen where possible to be equipotent in terms of pharmacological activity. The series was typified by the compound BRL 16644 (2-[[3,4-dihydro-2,2-dimethyl-4-[3-(trifluoromethyl)phenyl]- 2H-1-benzopyran-7-yl]oxy]-N,N-dimethyl-ethanamine: Chemical Abstracts No. 59257-24-8). Five of these compounds were clearly teratogenic producing specific abnormalities typified by anasarca, brachygnathia and cleft palate. Similar levels of maternal toxicity, particularly stereotypic behaviour, and foetotoxicity were seen in both teratogenic and non-teratogenic compounds suggesting that neither maternal nor foetotoxicity plays a role in the aetiology of the abnormalities. Four of the teratogenic compounds contained a trifluoromethyl group in the 4-phenyl ring and, within this series of compounds, substitution with this group appears to confer teratogenicity. Although equipotent doses were used this only pertained to the adult and as only limited pharmacokinetic data were available, including the extent of placental transfer, the influence of this group is not clear. Investigations have been undertaken to relate the teratogenic potential of these compounds to a number of their chemical descriptors, including electronic, steric, quantum chemical and hydrophobicity parameters, to try and clarify the influence of the trifluoromethyl group.

The continuing case study

A continuing case study highlighting one extended family was used with generic and RN baccalaureate nursing students to integrate basic nursing concepts, nursing theory, and health assessment content in an integrated curriculum. Unlike traditional case studies, the continuing case study allowed people and health states to change over time, providing a new dimension to case analysis. This method facilitated the application of theory to practice situations and helped students to understand the dynamics of family health.

Assessing parents as health educators

Parental health knowledge and beliefs are critical determinants in decisions concerning health care matters of children. This article describes a data collection instrument based on Orem's Self-Care Theory that can predict the potential for health education in the home.

A record-linkage study of mortality and general hospital discharge in patients diagnosed as schizophrenic

Six hundred people diagnosed as schizophrenic by the specialist psychiatric services in Oxfordshire, between 1971 and 1973, were identified from the Oxford Psychiatric Case Register (OPCR). The person records of deaths and hospital discharges held by the Oxford Record Linkage Study (ORLS) wee used to examine the following items of information for members of this group: details of discharges from an surgical operations performed in Oxfordshire non-psychiatric hospitals in a 6-year period before and a 4-year period after the date of first inclusion in the OPCR, and details of deaths in a 4-year period after the date of first inclusion in the OPCR. The numbers of deaths, discharges and operations so observed in the study group were compared in age, sex and major diagnostic groups with the expected numbers derived from rates prevailing in the Oxfordshire population over the same periods. Observed deaths were twice as numerous as expected in both sexes, and the numbers of general hospital discharges were also higher than expected. Ischaemic heart disease was the commonest cause of death in both sexes, but did not account for the excessive numbers of hospital discharges. Trauma and poisoning accounted for the excess both of deaths in younger members of the study group and of general hospital discharges overall. Social and environmental difficulties associated with the diagnosis schizophrenia are likely to have contributed more than any inherent biological disadvantage to this excess.

Maternal anti-nauseants and clefts of lip and palate

1 Data on drug prescriptions were obtained from the general practitioners of 196 women who had had infants with clefts of lip or palate and those of 407 control women, matched for age, parity, social class and year of delivery. 2 There was no excess of index women who had presented with nausea or vomiting. 3 There was a significant excess (12 cases, nine controls, P less than 0.02) of women who had been prescribed Debendox (the 3-constituent, or pre-1976, formulation of Bendectin) in early pregnancy. 4 This result was not thought to be conclusive evidence of a teratogenic effect but caution in prescribing is advised pending more extensive studies.

Previous hospital care as a risk factor for pneumonia. Implications for immunization with pneumococcal vaccine

In the Oxford Record Linkage Study population in 1970, seven hundred ninety-three persons were hospitalized for or died as a result of pneumonia. Thirty-six percent who survived and 49% who died had been discharged from hospital within the previous five years. For the period 1963 through 1970, cohort analysis determined the probability of subsequent readmission and/or death caused by pneumonia within the next five years for patients discharged with any condition and with high-risk conditions only. From this analysis, it was estimated that pneumococcal immunization of relatively few discharged patients would prevent each subsequent readmission and death from pneumococcal pneumonia. These results suggest that, in addition to age and underlying medical condition, patterns of previous hospital care can be used to identify many persons at increased risk of developing pneumonia. If current patterns of previous hospital care are similar to those found in Oxfordshire, physicians should consider giving pneumococcal vaccine to patients who are discharged from hospitals.

Cancers of the large bowel: associated disorders in individuals

The individual medical histories in the files of the Oxford Record Linkage Study for the years 1963 to 1967 were analyzed to ascertain any previously unsuspected associations between cancers of the large bowel and other diseases in individuals, and to quantify the relative risks of disorders already known to be associated. In males significant associations were shown between cancers of the large bowel and cancer of the prostate. In females, cancer of the colon was associated with breast cancer, and cancer of the rectum with a mixed group of genital cancers. The relative risk of colorectal cancer associated with previous benign neoplasms of the large bowel was 20, and with ulcerative colitis, 25. There was no significant association with appendicitis or long-standing diverticular disease.

Disease associations in linked records: schizophrenia and accidental injury

The investigation to be reported in this paper was undertaken following a query concerning the relationship between road accidents and the use of psychotropic drugs. One aspect of this problem could be studied easily by using the file of linked records of the Oxford Record Linkage Study (Acheson, 1967; Baldwin, 1973). Statistical methods have been developed to estimate the degree of association between conditions occurring in time-ordered sequences (Baldwin et al, 1978). The existing file of linked hospital discharge and death records in the Oxford Record Linkage Study was therefore searched and relevant material analysed to test the hypothesis that admission to hospital for schizophrenia was followed by an increased risk of accident or injury. (The present data do not allow the more specific question of phenothiazine treatment to be investigated). The statistical procedures simultaneously provide data on the converse situation, namely where injury occurs prior to hospital admission with schizophrenia, and this was studied also.

Thyroid disease and asthma

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Consultation patterns in a general practice

A study from the Oxford Community Health Project is reported on the effects on consultation rates in general practice of patients' age, sex, date of registration, address, and usual doctor. The impact on consultation rates of accessibility of surgeries and availability of doctors is examined when the variables are controlled, and the importance of these factors is discussed in relation to planning primary medical care.

Confidentiality of psychiatric data in medical information systems

These documents were prepared by Dr J. A. Baldwin, Dr J. Leff and Professor J. K. Wing at the request of the Executive Committee of the Social and Community Psychiatry Group of the College. After extensive consultation they were approved by the Executive and Finance Committee as representing the policy of the Royal College of Psychiatrists.

Copies of the Code of Practice (Annex B), and of the unpublished Annex C, Technical Arrangements for Ensuring Confidentiality and Annex D, General Features of Medical Information Systems, are obtainable from Professor J. K. Wing, M.R.C. Social Psychiatry Unit, Institute of Psychiatry, De Crespigny Park, London SE5 8AF.

Epidemiology and family characteristics of severely-abused children

Severe child abuse in north-east Wiltshire was studied retrospectively during the period 1965-71, and prospectively for 18 months from January 1972, after a period of consultative activity with those actively involved to increase awareness of the phenomenon. Severe abuse was strictly defined. A rate of 1 per thousand children under four years old was obtained, together with a death rate of 0-1 per thousand. The families of the retrospective series of abused children were studied in detail and identifying characteristics of large family size, youthfulness, low social-class, instability, and gross psychiatric, medical, and social pathology described. The implications of the ascertainment and death rates are discussed in relation to data from some other studies, and the need emphasized for detailed studies of the apparent clustering of disorder in the families, using linked record systems.

Ehe incidence of cancer among in-patients with affective disorders

Mortality rates in psychiatric patients have been reported as higher than those of the general population in Scandinavia (Odegaard, 1952), the United States (Gorwitz et al., 1966; Babigian and Odoroff, 1968), and Scotland (Innes and Millar, 1970). These findings may be related both to a greater prevalence of physical disease amongst psychiatric patients (Kay and Roth, 1955; Culpan et al., 1960; Shepherd et al., 1964; Kay and Bergman, 1966; Eastwood and Trevelyan, 1972) and to a greater frequency of suicide (Stenstedt, 1952; Stenstedt, 1959; Pokorny, 1964).

Linked record medical information systems

Linked record medical information systems generate cumulative person or family records from data on events or processes occurring to the individual at separate times and places. The special purposes of time-based and family statistics from these systems are exemplified by studies in health care, epidemiology and genetics. Methods of linking records on a large scale and some of the difficulties are described. The value and practicability of computer-assisted linked record systems are discussed in the light of experience with the Oxford Record Linkage Study and the northeast Scottish Psychiatric Case Register, both of which have been in existence for a decade.