The experience of thought-disordered individuals preceding an aggressive incident

The purpose of this qualitative study was to increase the understanding of the experiences of individuals with thought disorders, which precede incidents of aggression. Twelve individuals, from two hospitals, who had a nursing diagnosis of thought disorder and a history of aggression were interviewed, between one and four times, to collect baseline information and information about particular aggressive incidents. The participants described in their own words their thoughts, feelings and experiences preceding the aggressive incidents. Three themes emerged. First, participants perceived themselves to be strongly affected by the external environment; their responses to aspects of the environment were influential in precipitating the aggressive incident. Second, participants perceived themselves, paradoxically, to be both powerful and powerless; the act of aggression becomes an incident of brief self-empowerment. Third, the aggressive incident occurred in spite of the participants' acknowledgement and previous use of anger-controlling strategies; the participants' perceptions of themselves as powerless in an oppressive environment may have mitigated against the success of these strategies. Nurses need to know what triggers aggressiveness in psychiatric patients, in order to intervene effectively. Mental health professionals must also reexamine the psychiatric hospital environment, to make sure they are not needlessly exacerbating their patients' powerlessness with policies that are unjustifiably controlling.

Fos-Jun dimerization promotes interaction of the basic region with TFIIE-34 and TFIIF

The regulation of RNA polymerase II-mediated transcription involves both direct and indirect interactions among regulatory proteins and the general transcription factors (GTFs) that assemble at TATA-containing promoters. Here we show that the oncogenic transcription factors Fos and Jun make direct physical contacts with three proteins of the basal transcription apparatus, TFIIE-34 (TFIIE-beta), TFIIF-30 (RAP30), and TFIIF-74 (RAP74). The interactions among the activator proteins and these three GTFs were not detected with other transcription factors, including some bZIP protein family members. Both coimmunoprecipitation and protein blotting experiments demonstrated that the interactions were strongly favored by dimerization of Fos and Jun and that they involved the basic region and basic region-proximal domain of both proteins. Mutations within the DNA-binding domains of Fos and Jun abolished binding to GTFs, although the presence of DNA was not required for the association. Surprisingly, only a single basic region in the context of a protein dimer was sufficient for the interaction. Squelching of AP-1-dependent transcription in vitro by an excess of Fos-Jun dimers was relieved by the addition of TFIIE, indicating that it is a direct functional target of Fos and Jun. These results suggest that dimerization induces a conformational alteration in the basic region of Fos and Jun that promotes an association with TFIIE-34 and TFIIF, thus contributing to transcription initiation.

Denaturing gradient gel electrophoresis to diagnose multiple endocrine neoplasia type 2

Multiple endocrine neoplasia type 2 (MEN 2) is an autosomal dominant cancer syndrome caused by mutations in the RET protooncogene. Others have already demonstrated the value of genetic testing in known MEN 2 kindreds. Previously described approaches to DNA-level diagnosis, particularly of index cases, are tedious. We developed appropriate denaturing gradient gel electrophoresis (DGGE) conditions for analysis of exons 10, 11, and 16 of this gene, where many of the pathogenic mutations map. We screened 16 members of a three-generation MEN 2 kindred by DGGE and found five affected but still asymptomatic patients, ranging in age from 5 to 67 years. We used DGGE to localize the pathogenic mutations and screen at-risk individuals in several other kindreds. DGGE--which requires no radioactive, fluorescent, or chemiluminescent labeling--is ideally suited to the diagnosis of MEN 2 because of the syndrome's dominant genetics and the rarity of clinically silent variants in the RET gene.

Health care access of poverty-level older adults in subsidized public housing

OBJECTIVE

To assess the health status, access and use of health care and unmet health care needs of poverty-level residents of the Seattle Housing Authority over the age of 62.

METHODS

An in-person interview survey of a quota sample of community residents.

RESULTS

About half of SHA residents reported problems accessing care and sixteen percent reported being denied care. Multivariate analysis showed that encountering barriers of health care use were associated with having insufficient funds for monthly living expenses and lack of transportation. Over 90% of the population knew where to seek health care, so knowledge about sources of care did not appear to be a barrier. SHA residents met or exceeded national goals for completion of six out of nine recommended exams and procedures. SHA residents had unmet needs for services not covered by Medicare or provided by visiting nurse services.

CONCLUSIONS

The results suggest that SHA residents know how to access medical care, and that visiting nurse services may be remarkably effective in meeting some medical care needs of SHA residents. It appears access to care by residents of subsidized housing could be improved by addressing transportation and financial barriers, and by providing more services to residents on site.

Quality of life of persons with urinary incontinence: development of a new measure

OBJECTIVES

Our objective was to develop a self-report quality of life measure specific to urinary incontinence (I-QOL) that could be used as an outcome measure in clinical trials and in patient care centers.

METHODS

The I-QOL was developed from interviews of 20 individuals with urinary incontinence. Refining the questionnaire was accomplished by structured interviews of 17 individuals with urinary incontinence. Testing the I-QOL's psychometric properties involved two administrations (n = 62) along with measures of psychologic well-being and functional status.

RESULTS

The rigorous development process ensured that the measure was complete and understandable. The I-QOL proved to be internally consistent (alpha 0.95) and highly reproducible (r = 0.93; 18 days; SD 4). For discriminant validity, severity of incontinence (P < 0.0001) and number of medical appointments in the past year to treat incontinence (P < 0.0001) significantly predicted I-QOL scores. Convergent validity analyses confirmed our predictions that the I-QOL scores were more closely related to overall well-being than bodily pain.

CONCLUSIONS

The I-QOL proved to be valid and reproducible as a self-administered measure for assessing quality of life of patients with urinary incontinence.

Site-specific isotope fractionation in the characterization of biochemical mechanisms. The glycolytic pathway

For a given biochemical transformation, such as the fermentation reaction, the redistribution coefficients, which relate the natural site-specific isotope contents in end products to those of their precursors, are a source of mechanistic information. These coefficients characterize the traceability of specific hydrogens in the products (ethanol and water) to their parent hydrogens in the starting materials (glucose and water). In conditions of complete transformation, they also enable intermolecular exchanges with the water medium to be estimated. Thus it is directly confirmed that hydrogens 1, 2, 6, and 6' of glucose are strongly connected to the methyl site I of ethanol obtained by fermentation by Saccharomyces cerevisiae. However, whereas hydrogens 6 and 6' are transferred to a great extent, transfer is only partial for hydrogen 2, and it is even less for hydrogen 1. Because the two moieties of glucose corresponding to carbons 1-2-3 and 4-5-6 are scrambled by the aldolase and triosephosphate isomerase reactions, additional exchange of hydrogens at positions 1 and 2 must have occurred before these steps. The value of the coefficient that relates site 2 of glucose to site I of ethanol in particular can be used to quantify the contribution of intermolecular exchange occurring in the course of the transfer from site 2 of glucose 6-phosphate to site 1 of fructose 6-phosphate mediated by phosphoglucoisomerase. The average hydrogen isotope effects associated with the transfer of hydrogen from the water pool to the methyl or methylene site of ethanol are estimated. In contrast to conventional experiments carried out in strongly deuterium-enriched media where metabolic switching may occur, the NMR investigation of site-specific natural isotope fractionation, which operates at tracer isotopic abundance, faithfully describes the unperturbed metabolic pathways.

Isolation of black creek canal virus, a new hantavirus from Sigmodon hispidus in Florida

Numerous rodents were trapped for serologic and virologic studies following the identification of a hantavirus pulmonary syndrome (HPS) case in Dade County, Florida. Cotton rats (Sigmodon hispidus) were the most frequently capture rodent and displayed the highest seroprevalence to a variety of hantavirus antigens. Hantavirus genome RNA was detected in all the seropositive cotton rats tested, using a reverse transcriptase-polymerase chain reaction (RT-PCR) assay. A virus was isolated from tissues of two seropositive cotton rats by cultivation of lung and spleen homogenates on Vero E6 cells. Nucleotide sequence information obtained by direct RT-PCR and the serologic relationships of this virus with the other hantaviruses indicate that this virus, Black Creek Canal virus, represents a new hantavirus distinct from the previously known serotypes.

Sexual knowledge interview schedule: reliability

The Sexual Knowledge Interview Schedule (SKIS) is a 46-item interview schedule with an abuse scale and knowledge scale. The knowledge scale includes feelings, body parts identification, body parts function and general sexual knowledge. The reliability of the SKIS is reported. Internal consistency for scales/subscales ranges from 0.78 to 0.96. Inter-rater reliability was 95.3% agreement and test-retest reliability was 70.1%.

Linking research and practice

Although nurses are expected to incorporate research findings into their practice and be accountable for their actions, they often lack support to carry out these professional responsibilities. Below, how a service agency facilitated the linkage between nursing research and practice at a Canadian hospital.

Increased risk of small intestinal atresia among twins in the United States

OBJECTIVE

To compare the prevalence of small intestinal atresia among twins and singletons in the United States.

DESIGN

Descriptive analysis.

MEASUREMENTS

The McDonnell Douglas Health Information System (MDHIS), a national registry of newborn diagnoses, 1982 through 1988; and the Metropolitan Atlanta Congenital Defects Program (MACDP), a registry of defects among infants in Atlanta, 1968 through 1989.

PATIENTS

Live-born infants with small intestinal atresia.

INTERVENTIONS

None.

MAIN RESULTS

In both systems, the rate of small intestinal atresia was higher among twins than singletons (MDHIS: 5.5 per 10,000 vs 2.0, relative risk [RR] = 2.8, 95% confidence interval [CI] = 1.9 to 4.0; MACDP: 7.3 vs 2.5, RR = 2.9, 95% CI = 1.5 to 5.7). The increase was more notable among same-sex twins than opposite-sex twins, suggesting an increase among monozygotic twins. It was also more notable among twins with jejunoileal atresia than those with duodenal atresia, suggesting a vascular cause in many cases.

CONCLUSION

Twins have a higher rate of small intestinal atresia than singletons, possibly due to vascular disruption in monozygotic twins.

Effects of estrogen on free fatty acid metabolism in humans

To determine whether estrogen directly affects effective adipose lipolysis, palmitate rate of appearances ([14C]palmitate) was measured in 15 postmenopausal women. Each volunteer was studied after > or = 2 mo of estrogen treatment and again after > or = 2 mo of estrogen deficiency. Plasma hormone concentrations were controlled and identical on the 2 study days with use of the pancreatic clamp technique, and the lipolytic response to epinephrine and epinephrine + phentolamine was assessed. Results showed that overall palmitate flux was greater (10-20%, P < 0.05) during the estrogen-deficient than during the estrogen-replete study. Adrenergic stimulation of lipolysis was not specifically influenced by estrogen treatment, and control of plasma hormone concentrations did not eliminate the difference in palmitate flux between the estrogen-deficient and estrogen-replete study days. We conclude that estrogen deficiency is associated with increased plasma free fatty acid availability and that estrogen likely has direct, albeit small, effects on adipose tissue lipolysis.

Descriptive epidemiology of small intestinal atresia, Atlanta, Georgia

To describe the epidemiology of small intestinal atresia (SIA) in Atlanta, Georgia, from 1968 through 1989, we used the Metropolitan Atlanta Congenital Defects Program, an active, population-based surveillance system for birth defects diagnosed during the first year of life. We identified 176 infants with SIA, a prevalence of 2.8 per 10,000 livebirths. Among black infants, the prevalence was 3.7 per 10,000 livebirths, significantly higher than the prevalence of 2.4 per 10,000 among white infants [relative risk (RR) = 1.6, 95% confidence interval (CI) = 1.1,2.1]. Nine infants were each one member of a unique pair of twins. The prevalence among twin infants was 7.3 per 10,000, significantly higher than the prevalence of 2.8 per 10,000 among singletons (RR = 2.7, 95% CI = 1.4,5.2). Forty-nine percent of the infants had duodenal atresia, 36% had jejunal atresia, and 14% had ileal atresia. Two infants (1%) had atresia at an unspecified site in the small intestine. We grouped the infants by anatomic location of SIA into four categories: isolated SIA (53%), SIA with multiple unrelated defects (21%), sequences (16%), and syndromes (10%). We then compared the isolated and multiple unrelated defects groups by gender, race, maternal age, birth weight and one-year mortality for each location of SIA. Among black infants the prevalence of isolated jejunal atresia was 1.4 per 10,000, significantly higher than the prevalence of 0.2 per 10,000 among white infants (RR = 6.3, 95% CI = 2.9, 13.5). The increased prevalence of these defects among twins was a particularly interesting finding.

Alcohol use before and during pregnancy. PRAMS Working Group

A woman's excessive drinking during pregnancy can cause structural and behavioral abnormalities in her offspring. However, population-based data concerning maternal drinking behaviors are sparse. To describe drinking prevalences and patterns, we analyzed self-reported data from the Pregnancy Risk Assessment Monitoring Systems of Maine, Michigan, Oklahoma, and West Virginia. During 1988 and 1989, 6,319 mothers were surveyed two to six months after delivery; state-specific response rates ranged from 65.6% to 83.5%. We applied statistical weights to the sample from each state; thus, the results estimate state-specific prevalences. State-specific prevalences of drinking during the last three months of pregnancy were low: 6.8% to 15.1% of mothers reported light drinking (one to six drinks per week), 0.06% to 0.30% reported moderate drinking (seven to 13 drinks per week), and 0.03% to 0.13% reported heavy drinking (14 or more drinks per week). In contrast, prevalences of drinking during the three months before pregnancy were much higher: the range was 31.9% to 53.8% for light drinking, 1.6% to 3.0% for moderate drinking, and 0.6% to 1.3% for heavy drinking. State-specific prevalences of mothers who reported receiving prenatal counseling about alcohol's effects ranged from 66.3% to 75.0%. More heavy drinkers than light drinkers received counseling. These findings indicate that moderate and heavy drinking during late pregnancy is relatively rare. However, all levels of drinking near the time of conception are much higher, and these results suggest the need for research into methods of reducing drinking before pregnancy.

Defining and classifying skin tears: need for a common language

Very little has been written about skin tears. A common taxonomy and definition for each type of skin tear can organize teaching, practice, and research in the field. In 1990, Payne and Martin published the results of a descriptive clinical nursing research study on the epidemiology and management of skin tears in older adults. The Payne-Martin Classification System for Skin Tears, definitions, and characteristics of skin tears were presented. The purpose of this article is to critique their classification system and definitions. Criteria for evaluating taxonomies, internal validity, external validity, and utility, are used for the critique. A revision based upon continuing research and work with the classification system is presented. Further testing and modification will refine the classification and advance the science of wound care.

Antispasmodic activity of benzylisoquinoline alkaloids analogous to papaverine

In vitro, reticuline, norarmepavine, coclaurine, and papaverine competitively antagonize the uterine muscular contractions induced by acetylcholine and calcium. The antagonism is more efficient for the alkaloid coclaurine which is even stronger than papaverine. The pA2 values obtained with each of the four alkaloids for both agents, acetylcholine and calcium, respectively, were as follows: reticuline (5.35 and 4.81), norarmepavine (5.55 and 4.09), coclaurine (7.42 and 6.91), papaverine (5.32 and 6.23). The two components, phasic and tonic, of the response of the vas deferens to potassium are reduced by the four alkaloids. The reduction is greater for the tonic phase, with the following IC50 values: reticuline 474 microM, norarmepavine 101 microM, coclaurine 68.9 microM, and papaverine 14.3 microM. The antispasmodic activity of the three alkaloids, similar to papaverine, is related to an inhibiting effect of extracellular calcium, an intracellular effect, or both.

Radioimmunoassay screening of dried blood spot materials for benzoylecgonine

Residual samples of blood spots, which are routinely collected on almost all newborns in the United States, can be used to determine seroprevalence information on newborns and maternal exposures to various substances, including drugs of abuse. By modifying a commercial radioimmunoassay (RIA) kit for urinary samples, one can use blood spotted on filter paper as a matrix to quantitate the cocaine metabolite benzoylecgonine (BE). BE is stable for long periods of time in blood spots and we were able to quantitatively extract it with aqueous buffer. There were no matrix effects of the blood spot eluate on the RIA, and excess lipid in the blood did not alter measurement of BE. By using standards made up of BE in negative blood spot eluate and calibrators of blood that were spiked with BE and then spotted on filter paper to determine extraction efficiency, low levels of BE in blood could be measured. The limit of detection was 5 ng/mL, and the limit of quantitation was 10 ng/mL. Levels of BE in blood collected at autopsy in eluates of blood spots were measured, and they established excellent correlation (r2 = 0.93) with gas chromatography/mass spectrometry measurements. To test this technology, residual blood spots on 545 infants from three states were analyzed for BE.

Baculovirus expression of the glycoprotein gene of Lassa virus and characterization of the recombinant protein

A recombinant baculovirus was constructed that expresses the glycoprotein gene of Lassa virus (Josiah strain) under the transcriptional control of the polyhedrin promoter. The expressed protein (B-LSGPC) comigrated with the authentic viral glycoprotein as observed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), was reactive with monoclonal antibodies (MAbs) in Western blots, and was glycosylated. Although the recombinant protein was not processed into the mature glycoproteins, G1 and G2, it demonstrated reactivity with all known epitopes as measured by indirect immunofluorescence (IFA), and it was immunogenic, eliciting antisera in rabbits that recognized whole virus in IFAs. Regarding future applications to diagnostic assays, the recombinant glycoprotein proved to be an effective substitute for Lassa virus-infected mammalian cells in IFAs and it was able to distinguish sera from several human cases of Lassa fever, against a panel of known negative sera of African origin, in an enzyme immunoassay (EIA).

Cocaine and single ventricle: a population study

A recent case report by Shepard et al. (Teratology 43:113-117, 1991) suggested that single ventricle may result from maternal cocaine ingestion by inducing coronary occlusion in the developing fetal heart. We used data from the Atlanta Birth Defects Case-Control Study and the Metropolitan Atlanta Congenital Defects Program (MACDP) to investigate the role of maternal cocaine ingestion in the induction of single ventricles. We identified through the MACDP 58 case infants with a single ventricle, 27 who were study subjects in the Atlanta Birth Defects Case-Control Study, and 31 who were not. We conducted a case-control study with the 27 Atlanta Birth Defects Case Control Study infants, frequency-matched to control infants by race, hospital of birth, and calendar quarter of birth. None of the 27 case infants were exposed to cocaine during early pregnancy, but 7 (0.43%) of the control infants were exposed during early pregnancy. Using MACDP data, we conducted an analysis of trends for prevalence of single ventricle in the metropolitan area. No upward trend in single ventricle was detected for 1968 through 1990. Our data suggest that even if maternal cocaine ingestion during pregnancy is a cause of single ventricle, most cases appear to be unrelated to this exposure.

Trends in rates of multiple vascular disruption defects, Atlanta, 1968-1989: is there evidence of a cocaine teratogenic epidemic?

Research suggests that, perhaps through mechanisms initiated by vasoconstriction and leading to vessel thrombosis or embolism, cocaine causes vascular disruption defects, and that frequent cocaine use during early pregnancy could disrupt multiple organ systems in the fetus. We hypothesized that if cocaine is an important cause of multiple vascular disruption defects, a rising prevalence of cocaine use by mothers during pregnancy should be accompanied by rising rates of these defects in their offspring. Using data from the Metropolitan Atlanta Congenital Defects Program, we identified all infants born in Atlanta from 1968 through 1989 who had nonsyndromic, provisional vascular disruption defects affecting more than one organ system: 61 infants (78%) had gastrointestinal and genitourinary defects, 7 (9%) had gastrointestinal and abdominal wall defects, 2 (3%) had gastrointestinal and limb reduction defects, 2 (3%) had limb reduction and abdominal wall defects, 2 (3%) had central nervous system and gastrointestinal defects, 2 (3%) had genitourinary and limb reduction defects, 1 (1%) had genitourinary and abdominal wall defects, and 1 (1%) had central nervous system and genitourinary defects. The prevalence of Atlanta infants with more than one vascular disruption defect is 0.13 per 1,000 live births. Chi-square analysis for trends showed no increase in prevalence during the study period. Our data are from one of the first population-based studies in which trends for defects potentially caused by maternal cocaine use are examined; the results of our study show no significant change in the prevalence of multiple vascular disruption defects over time.(ABSTRACT TRUNCATED AT 250 WORDS)

Alternative approaches to nursing practice: application of Peplau, Rogers, and Parse

This article demonstrates three major nursing theories in practice. The uniqueness of each theory is clarified through the presentation of nursing formulations and practice implications. The discussion provides a metaperspective of how practice based in nursing theory is different from traditional practice and how nursing theory can guide practice.

Transient heat shock in mid-G1-phase of the C6 glioma cell cycle impairs entry into S-phase

Synchronous populations of rat C6 glioma cells have been obtained by a mitotic selection procedure and used to establish the effect of transient temperature elevation on their progression through the cell cycle. A transient 3-h exposure to a 42 degree C heat shock within defined area in the mid-G1-phase of the cell cycle has been demonstrated to impair progression to S-phase. This anti-proliferative heat shock effect was not apparent in asynchronous cell populations. A small, but significant, decrease in 3H-thymidine incorporation was observed (approximately 5%) following an 8-h exposure to heat shock.

Determination of site-specific carbon isotope ratios at natural abundance by carbon-13 nuclear magnetic resonance spectroscopy

Site-specific natural isotope fractionation of hydrogen studied by deuterium NMR (SNIF-NMR) spectroscopy is a powerful source of information on hydrogen pathways occurring in biosyntheses in natural conditions. The potential of the carbon counterpart of this method has been investigated and compared. Three typical molecular species, ethanol, acetic acid, and vanillin, have been considered. Taking into account the requirements of quantitative 13C NMR, appropriate experimental procedures have been defined and the repeatability and reproducibility of the isotope ratio determinations have been checked in different conditions. It is shown that the carbon version of the SNIF-NMR method is capable of detecting small differences in the carbon-13 content of the ethyl fragment of ethanols from different botanical or synthetic origins. These results are in agreement with mass spectrometry determinations of the overall carbon isotope ratios. Deviations with respect to a statistical distribution of 13C have been detected in the case of acetic acid and vanillin. However, since the method is very sensitive to several kinds of systematic error, only a relative significance can be attached at present to the internal parameters directly accessible. Isotope dilution experiments have also been carried out in order to check the consistency of the results. In the present state of experimental accuracy, the 13C NMR method is of more limited potential than 2H SNIF-NMR spectroscopy. However it may provide complementary information. Moreover it is particularly efficient for detecting and quantifying adulterations that aim to mimic the overall carbon-13 content of a natural compound by adding a selectivity enriched species to a less expensive substrate from a different origin.

Participation of older adults in health programs and research: a critical review of the literature

This collection of five papers evaluates the participation of older adults in clinical trials, health promotion/disease prevention initiatives, and health programs designed to maintain or improve the functioning of chronically ill older adults. Understanding the willingness or unwillingness of older adults to participate in these programs is critical to the development and implementation of health programs and policies for this population. In this introductory paper we briefly review illustrative literature to provide both an overview of the participation of older adults in health programs as well as background information relevant to the symposium papers.

Effects of body fat distribution on regional lipolysis in obesity

To determine the contribution of the major body fat depots to systemic free fatty acid (FFA) availability, palmitate ([1-14C]-palmitate) release was measured from leg (lower body) and non-leg (upper body) fat in eight upper body obese (UB Ob), six lower body obese (LB Ob), and six nonobese (Non Ob) age-matched premenopausal women in the overnight postabsorptive state. Splanchnic palmitate release was determined in 16 of these subjects.

RESULTS

total palmitate release was greater in UB Ob (P less than 0.005) than LB Ob or Non Ob women (161 +/- 16 vs. 111 +/- 9 vs. 92 +/- 9 mumol/min, respectively). Despite increased leg fat mass in obese women, leg palmitate release was similar in each group. Therefore, leg fat palmitate release was greater in Non Ob women than LB Ob (P less than 0.01) or UB Ob (P = 0.06) women (3.7 +/- 0.3 vs. 2.4 +/- 0.2 vs. 2.7 +/- 0.2 mumol.kg fat-1.min-1, respectively). Upper body fat palmitate release was less (P less than 0.01) in LB Ob than Non Ob or UB Ob women (3.0 +/- 0.4 vs. 5.0 +/- 0.3 vs. 4.9 +/- 0.4 mumol.kg fat-1.min-1, respectively). Splanchnic palmitate release accounted for 20-32% of upper body fat palmitate release in each group (P = NS between groups). Leg fat palmitate release was significantly less than upper body fat palmitate release. We conclude that the major difference in resting FFA metabolism between UB Ob and LB Ob women is the ability of the later to down-regulate upper body fat lipolysis to maintain normal FFA availability.

The anticonvulsant valproate teratogen restricts the glial cell cycle at a defined point in the mid-G1 phase

Direct cell counting and extent of [3H]thymidine incorporation demonstrated valproate to inhibit C6 glioma proliferation rate in a dose-dependent manner with a 1 mM concentration achieving 50% inhibition. The antiproliferative effect was reversible and could not be attributed to cytotoxicity at the valproate concentrations employed. The site of valproate action within the cell cycle was determined to be in the G1 phase, at a point 6-6.5 h prior to S phase, by estimating the time to increased [3H]thymidine incorporation following release from a 70% proliferative arrest. Synchronised cells obtained by a mitotic selection procedure required 11-12 h to enter S phase and demonstrated the valproate restriction point to be 5 h into the G1 phase of the C6 cell cycle. Exposure of valproate to the part of the G1 period which follows the restriction point was without effect on cell entry into S phase.

Isolation of Escherichia coli serotype O157:H7 and other Shiga-like-toxin-producing E. coli from dairy cattle

We examined 1,266 fecal specimens from healthy cattle during the investigations of two sporadic cases of hemolytic uremic syndrome associated with raw milk consumption and an outbreak of gastroenteritis and hemolytic uremic syndrome caused by Escherichia coli serotype O157:H7. We collected specimens from heifers, calves, and adult cows on 22 farms, in a stockyard, and in a packing house. We also collected 3 raw hamburger specimens from a restaurant and 23 raw milk samples from two farms. All specimens were examined for E. coli O157:H7 by using sorbitol-MacConkey agar, H immobilization, O157 agglutination, and tissue culture cytotoxicity. E. coli O157:H7 was isolated from 16 heifers or calves and 1 adult cow on 22 farms, 1 stockyard calf, 2 beef specimens, and 1 raw milk sample. Selected fecal specimens were also examined for the presence of other Shiga-like-toxin-producing E. coli (SLTEC) by testing polymyxin B extracts of colony sweeps and then testing individual colonies for toxin production. SLTEC other than O157 was isolated from 8 of 10 farms investigated and from the stockyard; 8% of adult cows and 19% of heifers and calves were positive for SLTEC. Several animals were positive for SLTEC by colony sweep only. This investigation demonstrates that dairy cattle are a reservoir of E. coli O157:H7 and other SLTEC.

Are offspring of women with hereditary hematologic disorders at increased risk of congenital cardiovascular malformations?

Hereditary hematologic disorders (HHD) have been reported in excess among infants and families of infants with congenital cardiovascular malformations (CCM) compared with controls, suggesting possible common pathogenetic mechanisms. It is plausible that hemodynamic changes during pregnancy associated with HHD could affect cardiac morphogenesis. To investigate whether offspring of women with selected HHD have an excess risk of CCM, the authors examined data from a nationwide birth defects monitoring program (BDMP) covering about 2.9 million births in the United States between 1982 and 1988. The system ascertains major birth defects diagnosed in the newborn period. An anonymous linkage procedure linked maternal obstetric records with newborn records using demographic, diagnostic, and geographic variables. A total of 1,239 mothers were identified with selected HHD (47 hereditary spherocytosis, 575 thalassemias, 310 sickle cell anemia, 88 other hereditary hemolytic anemias, 159 von Willebrand disease, and 60 other congenital coagulopathies). In all, 14 infants received a newborn discharge diagnosis of CCM (expected number based on population rates of CCM from the same hospitals and time period is 7.74; P = 0.0268). No single CCM entity accounted for this excess. In contrast, 8 infants had major non-CCM defects (expected number 7.46; P = 0.466). These data suggest an excess risk of CCM among offspring of women with selected HHD. Further studies are needed to explore these findings and to evaluate the pathogenetic significance of this association.

A collaborative model for the clinical education of baccalaureate nursing students

Quality clinical supervision is fundamental for the consolidation of knowledge and the development of a professional identity for baccalaureate nursing students. Problems in providing high-quality clinical supervision range from a lack of practitioner role models to inadequate or unsupportive learning environments. Collaboration between the education and service sectors allows for the development of enriched clinical learning experiences for students. This paper describes an innovative collaborative educational process developed by McMaster University School of Nursing and the Nursing and Education Departments at Hamilton Psychiatric Hospital, Hamilton, Ontario, Canada. Front-line nursing staff are the clinical supervisors, with support from clinical nurse specialists, the hospital educator and the university faculty member. When compared to more traditional approaches, this model ensures that the students receive more variety in placements and access to expert human resources.

Arrhythmias in patients with CHF. Should they be treated?

Ventricular arrhythmias are a major cause of death in patients with congestive heart failure. Dr Ellenbogen and his associates discuss the current thinking, based on recent studies, concerning use of antiarrhythmic agents to prevent sudden cardiac death in these patients. As they point out, the proper antiarrhythmic therapy may be crucial to long-term survival.

Descriptive epidemiology of selected malformations of the aorta, Atlanta, 1970-1983

To augment available population-based epidemiologic data for obstructive malformations of the aorta, we studied the descriptive epidemiology of coarctation, hypoplasia, and interruption of the aortic arch in Atlanta from 1970 through 1983. The study used data from the Metropolitan Atlanta Congenital Defects Program, a population-based birth defects registry. One hundred seventy infants were identified as having either interruption of the aortic arch (18), coarctation (131), or hypoplasia (21) of the aorta. The prevalence per 10,000 live births was as follows: interruption of the aortic arch, 0.50; coarctation, 3.62; and hypoplasia of the aorta, 0.58. Despite the differences in rates, the descriptive epidemiology for the three malformations was similar. None of the malformations was associated with gender or maternal age. Birth prevalence for whites was higher than that for other races; the increase, however, was statistically significant only for coarctation. Birth prevalence of these malformations increased during the period of observation, with the greatest increase (threefold) seen with interruption of the aortic arch. The rates for all malformation groups also showed a strong inverse association with birthweight.

Antihistaminic activity of pulegone on the guinea-pig ileum

Pulegone, a natural monoterpene compound, has an antihistamine effect on guinea-pig ileum. Its antagonism is of the competitive type (PA2 = 6.35) like that of mepyramine and dexchlorpheniramine, two H1-antagonists, with PA2 values of 10.15 and 8.74, respectively.

2H-NMR resolution of the methylenic isotopomers of ethanol applied to the study of stereospecific enzyme-catalysed exchange

We have shown that site-specific natural isotope fractionation of hydrogen studied by NMR (SNIF-NMR) is an important source of information on the mechanistic and environmental effects which govern the photosynthesis of sugars and their fermentation into ethanol. Three isotope ratios associated with the methyl, methylene, and hydroxyl sites of ethanol are determined in achiral media. In this study we show that complementary information about possible stereospecific mechanisms involving the methylenic hydrogens is also rendered accessible by 2H-NMR enantiomeric resolution. The synthesis of mandelate esters enables exchange between the pro-R site of ethanol and water to be investigated. Simultaneous access to the three site-specific isotope ratios of the ethyl group is obtained at isotopic dilutions close to the natural ones. Mediation of the exchange by the enzymic system alcohol dehydrogenase-alpha-lipoyldehydrogenase and by the yeast Saccharomyces cerevisiae are compared. The progress of the reaction can be followed quantitatively as a function of time and the occurrence of glycolytic metabolism of endogeneous materials by yeast can be substantiated in a one-pot experiment.

In vitro screening for anticonvulsant-induced teratogenesis in neural primary cultures and cell lines

To establish inherent potential for the induction of neural tube defects the ability of selected anticonvulsant agents to interfere with cell division has been established in vitro using an antiproliferative assay in clonal cell lines and a cytotoxicity assay using primary cultures of cerebral cortex neurons at different stages of development. In order to evaluate the relative toxicities of these agents their in vitro effects were determined at 2-3 times the plasma therapeutic level. By these procedures valproate and the benzodiazepines, diazepam and clonazepam, exerted a potent antiproliferative action which could not be attributed to increased cytotoxicity. In contrast phenytoin was markedly cytotoxic but was without an antiproliferative action. This cytotoxicity was most pronounced during the periods of extensive fibre outgrowth. When compared to epidemiological and animal study data, agents which inhibited cell proliferation within twice therapeutic concentration were consistently associated with major neural tube malformations. However phenytoin, found to be positive in the cell cytotoxicity assay, is not associated with neural tube malformations but rather is primarily associated with mental retardation. Thus assessment of antiproliferative activity of anticonvulsant drugs may be one criterion for identification of teratogenic potential during neurulation.

Hand and wrist fractures in occupational medicine

Hand fractures are so common in the workplace that a wide variety of physicians see and treat these injuries on a daily basis. This article is designed to assist in their primary diagnosis and care, as well as to recommend when it is best to arrange treatment by a hand specialist.

Health education: special issues for older adults

The older adult population in the United States has grown substantially since the turn of the century. With extended longevity and the relatively good functional status of most older adults, prevention programs that identify and intervene on risk factors in older adults may be an effective means to dealy ill health. The availability of data to guide both the selection and evaluation of prevention services for older adults, however, is strikingly limited in virtually all areas. Until recently, all persons over the age of 65 were treated as a single category of older adults although the older population is very heterogeneous. Most agree that prevention and education for this age group should focus on the prevention of disease, maintenance of existing abilities, and on prevention of deterioration of impairments that result in dysfunction or handicap. The most effective methods for developing behavioral intervention strategies may result from an integration of the behavioral diagnostic framework and current value expectancy and social learning theories. Health education interventions based on these strategies can be very effective in older age groups in terms of both improving adherence behavior with therapeutic and prevention intervention, and potentially in reducing morbidity and excess mortality.

Uterine inhibitory effect of reticuline

Reticuline, the most abundant benzylisoquinoleic alkaloid of Laurobasidium lauri, exerts a uterine inhibitory effect mainly related to a decrease in the concentration of cytosolic calcium available for contraction.

The anticonvulsant sodium valproate specifically induces the expression of a rat glial heat shock protein which is identified as the collagen type IV receptor

A potential mechanism for valproate (VPA)-induced increases in glial cell-substratum adhesivity has been demonstrated. Metabolically labelled glioma (C6) and primary astrocytes showed a statistically significant accumulation of protein when cultured in the presence of therapeutic concentrations of VPA (1 mM). This was mainly accounted for by a 10-fold increase in the production of a single polypeptide of 43 kDa molecular weight. Fractionation studies and metabolic labelling with N-acetyl-D-mannosamine showed this to be a sialoglycoprotein which was plasma membrane-bound. VPA-induction of the polypeptide was apparently specific to glioma and primary astrocytes and was not observed in neuroblastoma (neuro-2a), fibroblasts (3T3), pituicytes (GH3) and epithelial cells (NCTC). The 43 kDa component of glia was demonstrated to be the receptor for type IV collagen by binding metabolically labelled and solubilised cells to Sepharose beads which had been individually coated with laminin, fibronectin and type IV collagen. The protein has also been shown to be a heat shock product as metabolically labelled glioma showed a 10-fold increase in its expression when cultured at 42 degrees C. This heat shock induced expression was transient and was in marked contrast to that seen with VPA where it increased with time and was sustained. The expression of 43 kDa is suggested to arise by VPA and heat shock induced delays in cell cycle progression and this is discussed in relation to teratogenic action.

Ultrastructure of human immunodeficiency virus type 2

The ultrastructure of human immunodeficiency virus type 2 (HIV-2) was determined by negative stain and thin section electron microscopy (EM). Some virus particles had surface projections about 10 nm in length which were evenly spaced. Nonidet P40-treated particles which were penetrated by stain revealed a distinctive off-centre cone-shaped core and, in addition, free-lying cores were also seen in detergent-treated preparations. The surface of the cores was composed of a layer of small subunits. The structure of HIV-2 determined by thin section EM was the same as that deduced by negative stain EM.