Postterm delivery among African Americans, Mexican Americans and Whites in Chicago.

OBJECTIVES: The purpose of the present study was to examine the effect of individual-level and community-level risk factors on the postterm delivery rates of infants born to African-American, Mexican-American, and non-Latino White mothers; and to compare postterm delivery rates between these ethnic groups. DESIGN: This is a population-based study. METHODS: We performed stratified and multivariate logistic regression analyses on a linked dataset of 1992-1995 Illinois vital records, 1990 United States Census income data, and 1995 Chicago Department of Public Health information. Communities with one or more high-risk characteristics (low median family income or high rates of unemployment, homicide or lead poisoning) were classified as impoverished. RESULTS: In Chicago, African Americans (N = 85,978) had a postterm rate of 4.3/1,000 and Mexican Americans (N = 47,266) had a postterm rate of 3.6/1,000, compared to 2.3/1,000 for non-Latino Whites (N = 48,601); relative risk (ninety-five percent confidence interval) = 1.9 (1.5-2.3) and 1.6 (1.2-2.0), respectively. Maternal age, education, marital status, parity, and prenatal care usage were associated with ethnic group-specific postterm delivery rates. In a multivariate logistic regression model for non-impoverished mothers, the adjusted odds ratios of postterm delivery for African Americans and Mexican Americans were 1.0 (0.5-3.2) and 1.0 (0.6-1.7), respectively. CONCLUSIONS: We conclude that African Americans and Mexican Americans have greater postterm delivery rates than do Whites; however, commonly cited individual and community-level risk factors account for most of the disparity.

Consumer research: in search of identity.

Although the consumer research field has made great progress over the past 30 years with respect to the scope, quality, and quantity of research, there are still significant disagreements about what consumer research is, what its objectives are, and how it should differ from related disciplines. As a result, the field appears to be rather fragmented and even divided on some fundamental issues. In this review we first examine the original vision for the field and its limitations. In the second section we explore the consequences of the ambiguity about the domain and identity of consumer research and the multidisciplinary influences on the field. In particular, we review key trends and "camps" in consumer research, which represent complementary and, in some cases, conflicting views regarding the main topics of investigation and how research is conducted. This review is based in part on systematic analyses of articles that have been published in the leading consumer research journals over the past 30 years. Finally, in the third section we revisit the question of what might differentiate the field from related disciplines, as well as the role of theory testing, studies of substantive phenomena, and relevance in consumer research.

Differing postneonatal mortality rates of Mexican-American infants with United-States-born and Mexico-born mothers in Chicago.

OBJECTIVES: This study sought to determine the relationship between maternal nativity and the postneonatal mortality rate of urban Mexican-American infants. DESIGN: This is a population-based study. METHODS: Stratified and logistic regression analyses were performed on a data set of 1992-1995 computerized birth-death records of all Mexican-American infants born to Chicago residents with appended 1990 United States Census income and 1995 Chicago Department of Public Health data. RESULTS: In Chicago, Mexican-American infants (N = 10,599) of US-born mothers had a postneonatal mortality rate of 3.2/1,000 compared to 2.1/1,000 for infants (40,813) of Mexico-born mothers; relative risk (95% confidence interval) equaled 1.5 (1.0-2.3). The adjusted odds ratio of postneonatal mortality was 1.4 (1.1-1.9) for Mexican-American infants of US-born mothers. The mortality rate due to preventable causes (sudden infant death syndrome, homicides, non-intentional injuries, and infections) for Mexican-American infants of US-born mothers was twice that of infants of Mexico-born mothers; relative risk (95% confidence interval) equaled 2.2 (1.3-3.8); this nativity differential persisted in non-impoverished communities. CONCLUSION: The postneonatal mortality rate of urban Mexican-American infants with US-born mothers exceeds that of infants with Mexico-born mothers. This nativity disparity is attributable to preventable causes.

Differential effect of ecologic risk factors on the low birthweight components of African-American, Mexican-American, and non-Latino white infants in Chicago.

This study explored the relationship between ecologic risk factors and infant birthweight. A stratified analysis was performed on all African-American, Mexican-American, and white infants born in Chicago in 1990. One half of African-American mothers (n = 26,799) resided in communities with multiple ecologic risk factors, yet their very low birthweight rates were unaffected by the number of these factors. By contrast, only 5% of Mexican-American mothers (n = 9913) and 5% of white mothers (n = 13,596) lived in communities with multiple ecologic risk factors. Their very low birthweights were twice that of infants born to mothers who resided in communities with no ecologic risk factors. These results indicate that ecologic risk factors affect the very low birthweight rates of Mexican Americans and whites but not African Americans.

Tumors with reduced expression of a cytotoxic T lymphocyte recognized antigen lack immunogenicity but retain sensitivity to lysis by cytotoxic T lymphocytes.

A murine solid tumor was transfected to express various levels of an allogeneic major histocompatibility complex class I gene (K216), in order to test the effect of the level of antigen expression on immunogenicity and sensitivity to lysis by cytotoxic T lymphocytes (CTL). The growth rates of clones of tumor cells expressing different levels of the transfected gene were similar in vitro and in nude mice. Although all tumor cells, including cells freshly isolated from growing tumors, were equally sensitive to lysis by specific CTL, only tumor cells expressing the highest level of the K216 antigen stimulated CTL and were rejected by normal mice. In contrast, tumor cells expressing lower levels of antigen failed to immunize for CTL and grew progressively in normal mice, despite retaining expression of the transfected gene and remaining fully sensitive to CTL-mediated lysis; thus, the threshold of antigen needed to stimulate CTL responses was considerably higher than that needed to lyse tumor cells. Reduction of K216 antigen expression from 100-fold to 40-fold above background, impaired significantly the ability of the tumor cells to induce a K216-specific immune response, while tumor cells expressing K216 at levels 2-fold above background were as susceptible to CTL-mediated lysis as tumor cells expressing 50-fold more antigen. The important implication of these findings is that some tumors occurring in nature may not be immunogenic but nevertheless express antigens which are potential targets for immune therapy.

A long-term study of penfluridol in chronic schizophrenia.

Penfluridol, a member of the novel diphenylbutylpiperidine class of antipsychotic drugs, is the first long-acting oral neuroleptic. The population of the present study consisted of 24 chronic schizophrenic patients (14 males, ten females) whose treatment with penfluridol was initiated in our previous open/double-blind trial lasting 32 weeks 1; mean age was 42.2 years and mean duration of illness, 15.4 years. During one additional year in an uncontrolled clinical study, penfluridol in the form of 20-mg capsuent procedures included BPRS, CGI, NOSIE, vital signs, and laboratory measurements. During this long-term treatment with penfluridol, the scores of a cluster of BPRS items that included emotional withdrawal, conceptual disorganization, motor retardation, uncooperativeness, and blunted affect showed a progressively significant improvement. This indicated that the Bleulerian primary symptoms in chronic schizophrenics can be improved by the long-term administration of this long-acting neuropleptic with concomitant betterment of social adaptation and activity. The percentage of failure was very low (four patients) and was marked by instability of psychopathology with periods of excitation. The incidence of extrapyramidal reactions necessitating the administration of an antiparkinsonian drug during the length of trial was 35 per cent. No serious effects nor significant laboratory test changes were observed.