Coping with the stress of a painful medical procedure

To evaluate its effect on procedure-related distress, the focus of attention was manipulated by providing training to hospitalized acute burn patients (n=42). Participants were randomly assigned to attention focusing (i.e. attending to procedural sensations) or music distraction (i.e. attention diverting) coping interventions, or to usual care during the target dressing change. Coping behavior (i.e. distraction, focusing, and three confounding methods, ignoring, catastrophizing, reinterpreting), tension and intrusiveness were evaluated 24 h retrospectively (i.e. for the prior procedure), during the targeted procedure, and 30 min after the target procedure. When coping during the target procedure by ignoring, reinterpreting, and catastrophizing were covaried, the music distraction group experienced significantly fewer intrusions, and the attention focus group had more intrusions. Additionally, secondary analyses revealed that coping by ignoring during the prior day's procedure significantly predicted higher procedural tension during, and more intrusions following, the targeted procedure. Suppression-based forms of emotion-focused coping may be enhanced by training in the use of an explicit distractor.

Telepathology overview: from concept to implementation

Telepathology is the practice of pathology at a distance by using video imaging and telecommunications. Significant progress has been made in telepathology. To date, 12 classes of telepathology systems have been engineered. Rapid and ultrarapid virtual slide processors may further expand the range of telepathology applications. Next-generation digital imaging light microscopes, such as miniaturized microscope arrays (MMA), may make virtual slide processing a routine laboratory tool. Diagnostic accuracy of telepathology is comparable with that of conventional light microscopy for most diagnoses. Current telepathology applications include intraoperative frozen sections services, routine surgical pathology services, second opinions, and subspecialty consultations. Three telepathology practice models are discussed: the subspecialty practice (SSP) model; the case triage practice (CTP) model; and the virtual group practice (VGP) model. Human factors influence performance with telepathology. Experience with 500 telepathology cases from multiple organs significantly reduces the video viewing time per case (P < .01). Many technology innovations can be represented as S-curves. After long incubation periods, technology use and/or efficiency may accelerate. Telepathology appears to be following an S-curve for a technical innovation.

Oral immunization with hepatitis B surface antigen expressed in transgenic plants

Oral immunogenicity of recombinant hepatitis B surface antigen (HBsAg) derived from yeast (purified product) or in transgenic potatoes (uncooked unprocessed sample) was compared. An oral adjuvant, cholera toxin, was used to increase immune responses. Transgenic plant material containing HBsAg was the superior means of both inducing a primary immune response and priming the mice to respond to a subsequent parenteral injection of HBsAg. Electron microscopy of transgenic plant samples revealed evidence that the HBsAg accumulated intracellularly; we conclude that natural bioencapsulation of the antigen may provide protection from degradation in the digestive tract until plant cell degradation occurs near an immune effector site in the gut. The correlate of protection from hepatitis B virus infection is serum antibody titers induced by vaccination; the protective level in humans is 10 milliunits/ml or greater. Mice fed HBsAg-transgenic potatoes produced HBsAg-specific serum antibodies that exceeded the protective level and, on parenteral boosting, generated a strong long-lasting secondary antibody response. We have also shown the effectiveness of oral delivery by using a parenteral prime-oral boost immunization schedule. The demonstrated success of oral immunization for hepatitis B virus with an "edible vaccine" provides a strategy for contributing a means to achieve global immunization for hepatitis B prevention and eradication.

Risk factors for adolescent marijuana use across cultures and across time

An integrated analysis of the data from 3 different studies was conducted to examine the early psychosocial predictors of later marijuana use among adolescents. Longitudinal analysis of interview data was performed. The data used in the analysis were derived from (a) a sample of 739 predominantly White adolescents representative of the northeastern United States, (b) a sample of 1,190 minority adolescents from the East Harlem section of New York City, and (c) a sample of 1,374 Colombian adolescents from two cities in Colombia, South America. In 2 of the samples, participants were interviewed in their homes, and in the 3rd study, participants were assessed in school. The predictors included a number of variables from (a) the personality domain, reflecting the adolescents' conventionality and intrapsychic functioning; (b) the family domain, representing the parent-child mutual attachment relationship and parental substance use; (c) the peer domain, reflecting the peer group's delinquency and substance use; and (d) the adolescents' own use of legal drugs. The dependent variable was adolescent marijuana use. The results of the analysis demonstrated remarkable consistency in the risk and protective factors for later marijuana use across the 3 samples, attesting to the robust nature of these predictors and their generalizability across gender, time, location, and ethnic/cultural background. These findings have important implications for designing intervention programs. Programs aimed at preventing adolescent marijuana use can be designed to incorporate universal features and still incorporate specific components that address the unique needs of adolescents from different groups.

Exposure to parental tobacco and alcohol use: effects on children's health and development

This review examines three ways in which parental tobacco and alcohol use compromises the physical and mental health of children: 1) direct exposure to the substances; 2) living with parents who may become ill from using these substances; and 3) children's modeling of parental substance use. Implications for prevention, intervention, and public education are discussed, and a reframing of the national dialogue on youth substance abuse is called for.

Vascular endothelial cell growth factor is an autocrine promoter of abnormal localized immature myeloid precursors and leukemia progenitor formation in myelodysplastic syndromes

Vascular endothelial growth factor (VEGF) is a potent angiogenic peptide with biologic effects that include regulation of hematopoietic stem cell development, extracellular matrix remodeling, and inflammatory cytokine generation. To delineate the potential role of VEGF in patients with myelodysplastic syndrome (MDS), VEGF protein and receptor expression and its functional significance in MDS bone marrow (BM) were evaluated. In BM clot sections from normal donors, low-intensity cytoplasmic VEGF expression was detected infrequently in isolated myeloid elements. However, monocytoid precursors in chronic myelomonocytic leukemia (CMML) expressed VEGF in an intense cytoplasmic pattern with membranous co-expression of the Flt-1 or KDR receptors, or both. In situ hybridization confirmed the presence of VEGF mRNA in the neoplastic monocytes. In acute myelogenous leukemia (AML) and other MDS subtypes, intense co-expression of VEGF and one or both receptors was detected in myeloblasts and immature myeloid elements, whereas erythroid precursors and lymphoid cells lacked VEGF and receptor expression. Foci of abnormal localized immature myeloid precursors (ALIP) co-expressed VEGF and Flt-1 receptor, suggesting autocrine cytokine interaction. Antibody neutralization of VEGF inhibited colony-forming unit (CFU)-leukemia formation in 9 of 15 CMML and RAEB-t patient specimens, whereas VEGF stimulated leukemia colony formation in 12 patients. Neutralization of VEGF activity suppressed the generation of tumor necrosis factor-alpha and interleukin-1beta from MDS BM-mononuclear cells and BM-stroma and promoted the formation of CFU-GEMM and burst-forming unit-erythroid in methylcellulose cultures. These findings indicate that autocrine production of VEGF may contribute to leukemia progenitor self-renewal and inflammatory cytokine elaboration in CMML and MDS and thus provide a biologic rationale for ALIP and its adverse prognostic relevance in high-risk MDS.

Exposure to violence, coping resources, and psychological adjustment of South African children

The effects of exposure to direct and vicarious political, family, and community violence on the adjustment of 625 six-year-old black South African children was examined. Ambient community violence was most consistently related to children's psychosocial outcomes. Resources in the form of individual child resilience, maternal coping, and positive family relationships were found to mitigate the adverse impact in all the assessed domains of children's functioning.

Consequences of adolescent drug use on psychiatric disorders in early adulthood

This article summarizes the existing literature on the relationship between adolescent drug use and abuse and the development of psychiatric disorders in adulthood. In recent years, there has been increased awareness of the co-occurrence of drug abuse and psychiatric disorders in adolescence and young adulthood. Few longitudinal studies, however, have examined specifically the impact of earlier drug use and abuse on later psychiatric disorders. The literature suggests three possible models to explain the relation between drug use and abuse and psychiatric disorders. According to the first model, adolescent psychiatric disorders precede drug use and abuse. A second model postulates that psychiatric disorders and drug use are correlated because they share one or more common aetiological factor(s). The third model posits that drug use and abuse predict or precede certain psychiatric disorders. We present data from a recent longitudinal study to support this latter model. As drug use and abuse have been shown to increase the likelihood of psychiatric disorders, it is clear that medical attention needs to be given to adolescents who use drugs of abuse. It is expected that a decrease in adolescent drug abuse should lead to an accompanying reduction in later psychiatric disorders.

Cardiovascular disease risk factors in 5-year-old urban South African children--the Birth to Ten Study

BACKGROUND

A birth cohort study, the Birth to Ten (BTT) study, commenced in the greater Johannesburg/Soweto metropole in South Africa in 1990. The overall BTT project collected antenatal, birth and early development information on these children as well as information that could help identify factors related to the emergence of risk of cardiovascular diseases (CVDs) in children.

OBJECTIVE

To determine CVD risk profiles and their determinants in 5-year-old children living in an urban environment in South Africa.

METHODS

Demographic and birth characteristics were collected on a sample of 964 5-year-olds whose parents agreed for blood samples to be taken from their children. The children's height and weight were measured using standardised procedures; blood pressure (BP) was measured with a Dinamap Vital Signs Monitor, and a non-fasting blood sample was drawn for lipid determinations. Information on exposure to tobacco smoke and additional health-related data were obtained by interview.

RESULTS

No differences were found between the birth weight and gestational age of the 5-year-old CVD participants and the remainder of the children studied at birth. The systolic BP was significantly different between ethnic groups, with the BP of the black children significantly higher than that of the Indian and white children, while the diastolic BP of black children was also the highest. White children had the highest mean total cholesterol (TC) and low-density lipoprotein cholesterol (LDLC) levels, significantly higher than those in the black community. The coloured children's TC level was also significantly lower than that of the whites, while the LDLC level of the Indian children was significantly higher than that of the blacks. Overall, 64% of the children were exposed to environmental tobacco smoke (ETS), with the white group having the lowest rate (45% exposed to ETS). The coloured children were most frequently exposed to ETS, with 40.6% having primary caregivers who smoked; of these children 42% lived in homes with two or more smokers.

CONCLUSIONS

Tobacco control legislation will protect South Africans against tobacco sales promotions. This will be the first step towards increasing the priority of chronic disease prevention, health promotion and appropriate care for chronic diseases and their risk factors on the South African health policy agenda. The groups of children that were studied carried differing but significant levels of CVD risk. This suggests that the promotion of a healthy lifestyle should start in childhood, and should target the risk factors found in each group.

Ethical issues in HIV vaccine trials in South Africa

In this review we describe the ethical issues central to local and international debates about HIV vaccine trials. These issues include the physiological and psycho-social risks of trial participation, the preventative interventions to be provided to participants, access to treatment for participants who seroconvert, access to an effective vaccine after the trial, the role of placebo-controlled trials, and obtaining informed consent.

Process options in hepatitis B surface antigen extraction from transgenic potato

The process conditions for recombinant hepatitis B surface antigen (HBsAg) extraction from transgenic potato were examined. The effects of temperature, the reducing agent beta-mercaptoethanol (BME), and proteinase inhibitors on the level of antigenic activity of recovered HBsAg were determined. Sedimentation profiles were performed to characterize HBsAg assembly into virus-like particles. Increasing the temperature of the sample for about 1 min increased the measured HBsAg antigenic activity. The optimum temperature was around 50 degrees C. A 3-fold enhancement of the antigenic activity was obtained in extract from transgenic potato expressing HBsAg, when monoclonal antibodies were used to assay for HBsAg. When antigenic activity was determined by polyclonal antibodies, no enhancement in the antigenic activity was obtained. Temperature may affect the conformation of the a epitope to which the monoclonal antibodies bind or alter the fluidity of surface lipid regions. BME increased the antigenic activity of HBsAg up to 4-fold when monoclonal antibodies directed against the a determinant were used, but there was no increase with polyclonal antibodies. This observation suggests that BME affects the structure or presentation of the a epitope. In the presence of BME and leupeptin, a proteinase inhibitor, higher antigenic activity was obtained. Leupeptin might protect the antigen, which might become more susceptible to proteolytic degradation after reduction, as a result of stimulation of sulfhydryl proteases. Although both temperature and BME increased the antigenic activity of HBsAg individually, when combined their interaction was antagonistic, resulting in reduced antigenic activity. Different proteinase inhibitors, including leupeptin, aprotinin, E-64, pefabloc, and pepstatin, had no significant effect on HBsAg from potato extract in a 2 h period in the absence of BME. The sedimentation profile of potato-produced HBsAg was determined in 5-30% sucrose gradients. Yeast-derived recombinant HBsAg was used as a positive control. The HBsAg from transgenic potato showed sedimentation and density properties that are very similar to the yeast-produced antigen, indicating assembly into virus-like particles. BME treatment did not change the sedimentation profile.

Needle sharing: a longitudinal study of female injection drug users

The objective of this study was to examine the psychosocial risk and protective factors related to needle-sharing behavior among female intravenous drug users (IDUs) positive (N = 96) and negative (N = 128) for human immunodeficiency virus (HIV). Participants in this longitudinal study were interviewed individually at two points in time, with a 6-month interval between interviews. The interviewers used a structured questionnaire, which included psychosocial measures and questions about drug and sexual risk behaviors. Data were analyzed using Pearson correlations and hierarchical regression analyses. The findings supported a developmental model in which the psychosocial domains and HIV status predicted T1 (initial) needle-sharing behavior, which in turn was related to T2 (follow-up) needle-sharing behavior. In addition, the relationship between personality and peer risk factors and T2 needle sharing was buffered by family-related protective factors. While HIV-positive status had a direct effect on T1 needle sharing with strangers, its effect was mediated by all of the psychosocial variables in its relation to T1 needle sharing with familiar people. Comparisons of these results were made with a companion study of male IDUs. The results suggest several intervention and treatment approaches that can be implemented at different points in the developmental pathways leading to risky needle-sharing practices among female IDUs.

Thioredoxin, a putative oncogene product, is overexpressed in gastric carcinoma and associated with increased proliferation and increased cell survival

Human thioredoxin is a putative oncogene that may confer both a growth and survival advantage to tumor cells. Overexpressed thioredoxin mRNA has been found in both primary human lung and colorectal cancers. To determine the intratumor distribution and amount of thioredoxin protein in human primary carcinomas, we developed an immunohistochemical assay for thioredoxin in paraffin-embedded tissue. We then studied 10 patients with primary high-risk gastric carcinoma. To further relate thioredoxin protein overexpression to cell death and survival, we used a paraffin-based in situ end-labeling (ISEL) assay. To delineate proliferation, we used the nuclear proliferation antigen detected by Ki-67. In this survey, we found that thioredoxin was localized to tumor cells and overexpressed compared with normal gastric mucosa in 8 of 10 gastric carcinomas. The thioredoxin was found at high levels in 5 of the 8 overexpressing carcinomas. The overexpression of thioredoxin was typically found in both a nuclear and cytoplasmic location in the neoplastic cells. There was a significant positive correlation (P = .0061) with cancer cell proliferation measured by Ki-67. There was a significant negative correlation (P = .0001) with DNA damage measured by the ISEL assay, suggesting decreased apoptosis and increased carcinoma cell survival. Thus, human primary gastric tumors that are highly expressive of thioredoxin have both a higher proliferative rate and a higher survival rate than tumors that do not express thioredoxin. With these newly developed assays in hand, it is now feasible to question whether this thioredoxin-related combined growth and survival advantage translates into poor clinical outcome.

Effects of parent personality, upbringing, and marijuana use on the parent-child attachment relationship

OBJECTIVE

To examine the predictors of the quality of the parent-child attachment relationship among a sample of 248 young adults with children.

METHOD

In this longitudinal study, data were collected during early adulthood in 1992 and in 1996/1997 via a structured questionnaire. Using logistic regression and multiple regression analyses, the authors assessed the extent to which participants' personality attributes, substance use, and relationships with their mothers predicted the quality of the parent-child bond.

RESULTS

Logistic regression models showed that participants with certain personality attributes (e.g., high sensitivity), less frequent marijuana use, or a close relationship with their mothers had a greater likelihood of having a close parent-child attachment relationship with their own children at a later time. Regression analysis also showed that the risk of earlier substance use on the parent-child relationship was offset by protective factors in the parents' personality domain. In addition, protective factors in the various parental domains synergistically interacted with a low frequency of marijuana use, relating to a closer parent-child attachment relationship.

CONCLUSIONS

The findings suggest that certain parenting styles are transmitted across generations and interventions in the personality and drug use domains can help increase the likelihood that parents will form close attachment relationships with their own children.

Coping strategies of HIV-positive and HIV-negative female injection drug users: a longitudinal study

This study longitudinally examined the psychosocial correlates of coping strategies among 165 HIV positive and 179 HIV negative female injection drug users (IDUs). Participants were interviewed twice using a structured questionnaire, with a 6-month interval between interviews. The questionnaire included psychosocial measures as well as measures of general coping and specific HIV-related coping. Data were analyzed using logistic regression analyses. The findings indicated that favorable factors in the psychosocial domains at Time 1 were significantly associated with an increased likelihood at Time 2 of the use of general coping and specific adaptive coping strategies, such as problem solving and seeking social support, and with a decreased likelihood at Time 2 of the use of maladaptive coping strategies, such as aggression and the use of illicit drugs. These findings highlight particular areas of psychosocial functioning that can be targeted by intervention programs to promote adaptive coping and minimize maladaptive coping among HIV positive and HIV negative female IDUs.

Chlorobium ferrooxidans sp. nov., a phototrophic green sulfur bacterium that oxidizes ferrous iron in coculture with a "Geospirillum" sp. strain

A green phototrophic bacterium was enriched with ferrous iron as sole electron donor and was isolated in defined coculture with a spirilloid chemoheterotrophic bacterium. The coculture oxidized ferrous iron to ferric iron with stoichiometric formation of cell mass from carbon dioxide. Sulfide, thiosulfate, or elemental sulfur was not used as electron donor in the light. Hydrogen or acetate in the presence of ferrous iron increased the cell yield of the phototrophic partner, and hydrogen could also be used as sole electron source. Complexed ferric iron was slowly reduced to ferrous iron in the dark, with hydrogen as electron source. Similar to Chlorobium limicola, the phototrophic bacterium contained bacteriochlorophyll c and chlorobactene as photosynthetic pigments, and also resembled representatives of this species morphologically. On the basis of 16S rRNA sequence comparisons, this organism clusters with Chlorobium, Prosthecochloris, and Pelodictyon species within the green sulfur bacteria phylum. Since the phototrophic partner in the coculture KoFox is only moderately related to the other members of the cluster, it is proposed as a new species, Chlorobium ferrooxidans. The chemoheterotrophic partner bacterium, strain KoFum, was isolated in pure culture with fumarate as sole substrate. The strain was identified as a member of the epsilon-subclass of the Proteobacteria closely related to "Geospirillum arsenophilum" on the basis of physiological properties and 16S rRNA sequence comparison. The "Geospirillum" strain was present in the coculture only in low numbers. It fermented fumarate, aspartate, malate, or pyruvate to acetate, succinate, and carbon dioxide, and could reduce nitrate to dinitrogen gas. It was not involved in ferrous iron oxidation but possibly provided a thus far unidentified growth factor to the phototrophic partner.

Platelet activating factor in stool from patients with ulcerative colitis and Crohn's disease

BACKGROUND/AIMS

Platelet activating factor (PAF) is a potent endogenous mediator in inflammatory processes. The role of this mediator, especially in connection with the unknown etiology of chronic inflammatory bowel diseases, remains poorly understood. A determination of PAF in stool may be helpful in recognizing quiescent inflammations in chronic inflammatory bowel diseases. A simple and reliable method for the determination of PAF in stool seems to be necessary to achieve this goal.

METHODOLOGY

PAF analysis was performed with the help of a commercial PAF radioimmunoassay (RIA) kit after solid phase extraction (SPE) of ethanolic stool extracts. PAF was determined in stool from 10 healthy volunteers (m = 4; f = 6), 13 patients with ulcerative colitis (m = 7; f = 6) and 15 patients with Crohn's disease (m = 9; f = 6). Fecal PAF concentrations were compared with activity index of disease, endoscopic index, localization of lesions, leukocyte count, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), medical prednisolone treatment, sex and age of the patients.

RESULTS

In healthy volunteers, no PAF was detectable in stool. In patients with Crohn's disease 319.2 +/- 143.5 pg PAF/g stool and in patients with ulcerative colitis 824.9 +/- 408.7 pg PAF/g stool could be determined. A significant correlation (p < 0.05) was found between PAF-content in stool and the endoscopical index and intestinal localization of inflammatory lesions. No further correlations could be detected in our patients.

CONCLUSIONS

Fecal PAF assessment may be used clinically as a non-invasive method to estimate severity of mucosal inflammation in patients with inflammatory bowel disease (IBD).

Adversity and psychosocial competence of South African children

Black children in South Africa commonly experience low socioeconomic status and community violence. Parents (N = 625) in a longitudinal study of urbanization responded to structured questionnaires related to resilience, affability, maturity, and school readiness of their six-year olds. SES was found to have an inverse and linear relation to competence at age six; the relationship to violence was curvilinear, with children from moderately safe communities achieving better outcomes than those from very safe or very unsafe ones.

Consequences of adolescent marijuana use: incompatibility with the assumption of adult roles

This longitudinal study is an examination of the relationship between marijuana use and the assumption of adult roles, as well as the relationship between assuming adult roles and the likelihood of later marijuana use. Data were collected at 5 points in time from childhood through early adulthood (late 20s) by means of a structured questionnaire. Participants' marijuana use and the assumption of adult roles, including employment, marriage, parenthood, and living arrangements, were measured, and the data were analyzed with logistic regression analyses. A history of marijuana use was associated with an increased risk of adopting more unconventional adult roles, such as postponement of marriage, having a child out of wedlock, and unemployment. These results suggest that frequent prior marijuana use may adversely affect one's ability to successfully assume conventional adult roles. Furthermore, controlling for earlier marijuana use, marriage during early adulthood significantly decreased the risk of later marijuana use.

Expression of vascular endothelial growth factor and its receptors in hematopoietic malignancies

Vascular endothelial growth factor (VEGF) plays an important role in angiogenesis by acting as a potent inducer of vascular permeability as well as serving as a specific endothelial cell mitogen. The importance of angiogenic factors such as VEGF, although clearly established in solid tumors, has not been fully elucidated in human hematopoietic neoplasms. We examined the expression of mRNA and protein for VEGF in 12 human hematopoietic tumor cell lines, representing multiple lineages and diseases, including leukemia, lymphoma, and multiple myeloma. Our results revealed that VEGF message was expressed in these cells and that the corresponding protein was secreted into the extracellular environment. Five of the 12 cell lines were also found to express the Flt-1 receptor for VEGF at a moderate to strong level, suggesting an autocrine pathway. When human vascular endothelial cells were exposed to recombinant human VEGF, there was an increase in the mRNA for several hematopoietic growth factors including macrophage colony-stimulating factor, granulocyte colony-stimulating factor and interleukin 6. Plasma cells in the bone marrow from patients diagnosed with multiple myeloma were found to express VEGF, whereas both the Flt-1 and KDR high affinity VEGF receptors were observed to be markedly elevated in the normal bone marrow myeloid and monocytic cells surrounding the tumor. These data raise the possibility that VEGF may play a role in the growth of hematopoietic neoplasms such as multiple myeloma through either a paracrine or an autocrine mechanism.

Beagle 2: a proposed exobiology lander for ESA's 2003 Mars Express mission

The aim of the proposed Beagle 2 small lander for ESA's 2003 Mars Express mission is to search for organic material on and below the surface of Mars and to study the inorganic chemistry and mineralogy of the landing site. The lander will have a total mass of 60kg including entry, descent, and landing system. Experiments will be deployed on the surface using a robotic arm. It will use a mechanical mole and grinder to obtain samples from below the surface, under rocks, and inside rocks. Sample analysis by a mass spectrometer will include isotopic analysis. An optical microscope, an X-ray spectrometer and a Mossbauer spectrometer will conduct in-situ rock studies.