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Surgical devices are often marketed before there is good evidence of their safety and effectiveness. Our paper discusses the ethical issues associated with the early marketing and use of new surgical devices from the perspectives of the six groups most concerned. Health Canada, which is responsible for licensing new surgical devices, should amend their requirements to include rigorous clinical trials that provide data on effectiveness and safety for each new product before it is marketed. Industry should comply with all Health Canada requirements to obtain licenses for new products. Until Health Canada requires effectiveness and safety data, industry should cooperate with physicians in appropriate studies before releasing new products and should make balanced presentations of all the available evidence. Surgeons should, before using a new surgical device, assess the evidence on its effectiveness and safety and ensure they are properly trained and competent in using the device. Surgeons should provide their patients with an evaluation of the available evidence and inform them about possible complications and the surgeon's level of experience with the new device. Patients, who should be given an honest evaluation of the available evidence, possible complications, and the surgeon's experience, should be encouraged to evaluate the evidence and information to their own satisfaction to ensure that fully informed consent is given. Health institutions, responsible for regulating practice within their walls, should review new devices for safety, effectiveness, and economic impacts, before allowing their use. They should also limit the use of new surgical devices to surgeons trained and competent in the new technology. Professional societies should provide guidance on the early adoption of new surgical devices and technologies. We urge all those involved in the development, licensing, and use of new surgical devices to aim for higher ethical standards to protect the health and safety of patients requiring surgery. The lowest acceptable ethical standard would require device manufacturers to provide surgeons with accurate and timely information on the efficacy and safety of their products, allowing surgeons and patients to evaluate the evidence (and the significance of information not yet available) before surgery.

Four hundred and twenty-two employees completed daily diaries measuring positive affect, negative affect, work hours, and health behaviors (snacking, smoking, exercise, alcohol, caffeine consumption) on work days over a 4-week period. In addition, measures of job demands, job control, and social support (iso-strain variables) were completed on 1 occasion. Multilevel random coefficient modeling was used to examine relationships between the job characteristics, daily work variables, and self-reported health behaviors. Results indicated a more important role for within-person daily fluctuations than for between-persons variations in predicting health behaviors. Whereas negative affect was negatively related to health behavior for both men and women, work hours had negative impacts for women only. Iso-strain variables showed few main effects and a modest number of interactions with daily variables (mainly for men). Findings point to the limited impact of stable features of work design compared to the effects of daily work stressors on health behaviors., ((c) 2007 APA)

Introduction: Pancreatic cancer is an extremely virulent form of cancer with few effective treatments. Catechin and inositol hexaphosphate (IP6), two naturally occurring molecules found in green tea and high-fiber foods, respectively, are compounds that have been shown to demonstrate anti-proliferative effects when administered as single therapeutic agents against a number of cancers. We hypothesized that, alone and in combination, IP6 and catechin would be effective against pancreatic cancer., Materials and Methods: Pancreatic (PANC-1 and MIAPACA) cancer cell lines were cultured and treated with IP6 (0.8 mM/well), catechin (100 microM/well), and the combination of the two. Cell viability was measured by 3-(4,5-dimethylthiazol-2-y1)-2,5-diphenyltetrazolium bromide (MTT) at 24, 48, and 72 h. Vascular endothelial growth factor (VEGF) was measured in the cell supernatants by ELISA. Apoptosis was evaluated by Annexin V-fluorescein isothiocyanate (FITC)., Results: The combination of catechin and IP6 significantly inhibited proliferation in the PANC-1 cell line at 24, 48, and 72 h compared to single agents (P < 0.001). Growth of the MIAPACA cell line was inhibited (P < 0.01) by each agent alone, but additive inhibitory effects were not seen. An increase in early apoptosis was attributed to catechin therapy in both cell lines (P < 0.01). The combination of these agents also increased early apoptotic activity when compared to the control (P < 0.001). IP6 reduced VEGF in both cell lines (P < 0.01). In combination, catechin and IP6 amplified VEGF reduction compared to each agent in MIAPACA and control (P < 0.002)., Conclusions: These results, combined with the prevalence of these compounds in safe, naturally occurring foods, make catechin and IP6 attractive therapies for treatment, and possibly in preventative trials, of pancreatic cancer.

Objectives: To examine the impact of anticipated regret within the theory of planned behaviour (TPB) on intentions of adolescents to initiate smoking. To examine the moderating role of anticipated regret and intention stability on the relationship between intentions and smoking initiation in adolescents., Methods: We conducted two studies measuring anticipated regret within the TPB applied to adolescent smoking initiation. In the first study, 347 non-smoking adolescents (between 11 and 12 years of age) completed the TPB and anticipated regret measures about smoking initiation. In the second study, 675 non-smoking adolescents (between 11 and 12 years of age) completed the TPB, anticipated regret, and intention stability measures in relation to smoking initiation. Smoking was assessed objectively by carbon monoxide breath monitor 9 months later., Results: In Studies 1 and 2, regret significantly added to predictions of intentions over and above components of the TPB (p < .001). In Study 2, smoking behaviour was predicted by intentions and the relationship of intentions to behaviour was moderated by regret and intention stability., Conclusions: Regret and intention stability were shown to be important variables within the TPB in understanding intentions and behaviour of smoking initiation in adolescents.

Objective: Repetitive concussive brain injury (CBI) is associated with cognitive alterations and increased risk of neurodegenerative disease., Methods: To evaluate the temporal window during which the concussed brain remains vulnerable to a second concussion, anesthetized mice were subjected to either sham injury or single or repetitive CBI (either 3, 5, or 7 days apart) using a clinically relevant model of CBI. Cognitive, vestibular, and sensorimotor function (balance and coordination) were evaluated, and postmortem histological analyses were performed to detect neuronal degeneration, cytoskeletal proteolysis, and axonal injury., Results: No cognitive deficits were observed in sham-injured animals or those concussed once. Mice subjected to a second concussion within 3 or 5 days exhibited significantly impaired cognitive function compared with either sham-injured animals (P < 0.05) or mice receiving a single concussion (P < 0.01). No cognitive deficits were observed when the interconcussion interval was extended to 7 days, suggestive of a transient vulnerability of the brain during the first 5 days after an initial concussion. Although all concussed mice showed transient motor deficits, vestibulomotor dysfunction was more pronounced in the group that sustained two concussions 3 days apart (P < 0.01 compared with all other groups). Although scattered degenerating neurons, evidence of cytoskeletal damage, and axonal injury were detected in selective brain regions between 72 hours and 1 week after injury in all animals sustaining a single concussion, the occurrence of a second concussion 3 days later resulted in significantly greater traumatic axonal injury (P < 0.05) than that resulting from a single CBI., Conclusion: These data suggest that a single concussion is associated with behavioral dysfunction and subcellular alterations that may contribute to a transiently vulnerable state during which a second concussion within 3 to 5 days can lead to exacerbated and more prolonged axonal damage and greater behavioral dysfunction.

This study employed the theory of planned behaviour (TPB) to investigate the factors underlying intentions and frequency of use of cannabis over a three-month period in a population of students (N = 249). In addition, several hypotheses in relation to the TPB were investigated. The TPB provided good predictions of both intentions (R2 = 0.653; attitude, injunctive norms and perceived behavioural control significant) and behaviour (R2 = 0.711; intentions significant). Other norm measures (descriptive and moral norms) explained additional variance in intentions (p < .01). In addition, habit strength and self-identity explained significant additional portions of the variance in intentions (p < .001), but not behaviour, over and above the TPB variables. Several interactions among these variables were also tested. Attitude moderated the impact of perceived behavioural control (PBC) on intentions (p < .001). Moral norms moderated the impact of attitudes on intentions (p < .001). Habit strength moderated the impact of self-identity on intentions (p < .001). PBC was found to moderate the impact of intentions on behaviour (p < .05). The findings are discussed in relation to how interaction effects further our understanding of the social processes by which variables are related in the TPB.

Community coalitions address a wide variety of community problems, espousing a community development processes that promotes individual and collective self-determination. They offer a promising venue for the study of empowerment of individuals and organizations. This study utilizes data from members of 35 community coalitions organized for the prevention of alcohol and other drug problems to address the following questions: What individual characteristics are related to the psychological empowerment of coalition members? What organizational characteristics are related to the collective empowering of members? What organization characteristics are related to a coalition being organizationally empowered to succeed in achieving its objectives? At the individual level, psychological empowerment was most strongly related to individuals' participation levels, sense of community, and perceptions of a positive organizational climate. At the group level, the strongest predictors of collective empowering (our operationalization of the empowering organization) were net benefits of participation, commitment, and positive organization climate. Psychological empowerment and positive organizational climate were the two predictors of organizational effectivenes (the empowered organization). Implications and limitations of these findings are discussed.

Radioligand receptor binding has been used extensively to identify and characterize a host of receptors and enzymes targeting virtually every therapeutic area. Many drug discovery programs have been based on the utilization of radioligand receptor binding technology to identify lead compounds which interact with receptors likely to be important in neuronal, immunological, gastrointestinal, and cardiovascular function/dysfunction. There are several obvious advantages to using in vitro receptor binding as a first level screen when compared to in vivo pharmacometric screens. Scientifically, the structure activity data generated in binding assays is a direct reflection of the ligand/receptor interaction minus the complications which result from secondary events, bioavailability, and pharmacodynamic issues. Technically, the binding studies require only a small amount of test compound (< or = 1 mg), while whole animal studies routinely need gram quantities. Similarly, only a small amount of tissue is required, compared with the cost of purchase and maintenance of live animals for in vivo screening. Supply and labor costs are drastically reduced due to the limited volume and test tube based technology of receptor binding. For these reasons receptor binding assays have been utilized with considerable success to discover site specific lead compounds in virtually every therapeutic area.

Sucralfate is used to induce healing of gastrointestinal tract ulcers. We evaluated its potential utility in the healing of skin wounds. Initial experiments examined the effects of the sucralfate on proliferation of cultured dermal fibroblasts and keratinocytes. Sucralfate induced proliferation in quiescent cultures of both cell types. Additionally, sucralfate enhanced prostaglandin E2 synthesis in basal keratinocytes and in interleukin-1-stimulated keratinocytes and dermal fibroblasts. Basal interleukin-1 and 6 release were not affected by sucralfate, but the agent enhanced interleukin-1-stimulated interleukin-6 release from fibroblasts. When applied daily to full-thickness wounds in rats, sucralfate increased the thickness of granulation tissue when assessed at day 12.

The oligonucleotide fingerprints of five of six strains of velogenic-viscerotropic Newcastle disease (VVND) virus were readily distinguishable, even though the strains could not be differentiated by a series of in vivo and in vitro procedures. Two of the VVND virus strains tested (10333-0 and 8231412) showed marked similarity to the prototype strain (MIL-0). Two of the remaining three strains (80-27489 and 80-28634) had identical oligonucleotide fingerprints, even though they had a different isolation history and exhibited small differences in their virulence for chickens. Fingerprints of the sixth VVND strain, 80-12927, demonstrated some similarities when it was compared with the prototype virus fingerprint, but it was quite different from strains 80-27489, 10333-0 and 8231412.

When mixtures of two clones of the Italy-Milano strain of Newcastle disease virus were inoculated so that one clone was present in quantities 20 times greater than the other, maintenance of that population ratio through six serial passages in 10-day-old embryonating chicken eggs depended on the multiplicity of infection of the first passage. The initial ratio was preserved when the eggs were inoculated at low multiplicity, 10(1) virions inoculated, but not at high multiplicity, 10(6) virions inoculated. In the latter situation, the clear plaque clone, which comprised 1/20 of the initial population of the inoculum, increased in numbers to parity with the red plaque clone after only six serial passages in embryonating eggs. Explanations for the competitive advantage of the clear plaque clone at high multiplicity of infection are discussed.

A telephone survey of 65 parents about their use of child rearing material showed that this was neither widely known nor frequently consulted; and that family doctors are seen to be the most common resource for information about child rearing problems.

A total of 426 persons were studied in an attempt to more clearly define the high prevalence of hepatitis-B surface antigen (HBsAg) seen among institutionalized persons. HBsAg was found in 63.4 percent of the children and young adults with Down's syndrome (DS) at the Central Wisconsin Center (CWC) and in 45.5 percent of those at the Northern Wisconsin Center (NWC). Significantly more subjects with DS had hepatitis-B antigenemia than age- and sex-matched non-DS institutionalized subjects. Antibody (anti-HBs) to HBsAg was found in 19.5 percent of the DS subjects at CWC and in 38.6 percent of those at NWC. The prevalence of anti-HBs was similar among DS and non-DS institutionalized subjects. None of the noninstitutionalized subjects had HBsAg in their serums and their anti-HBs prevalence was low (2.1 percent). HBsAg was found to persist for at least 10 years in both DS and non-DS institutionalized subjects. However, persistence occurred more frequently among DS subjects. Anti-HBs persisted at least 10 years among non-DS subjects, but DS subjects tended to lose antibody sooner. The study findings indicated that the high prevalence of HBsAg seen in institutionalized DS subjects at CWC and NWC were not related to the age of the subject at admission nor to the duration of institutionalization.

Lectin-binding profiles were developed for 14 strains of Newcastle disease virus in order to determine the carbohydrate moieties associated with hemagglutination and to establish whether there are any associations between the carbohydrates present on the virus envelope and virulence. All strains of Newcastle disease virus were bound by concanavalin A. Other lectins bound the viruses differentially, but there was no pattern of binding that could be associated with viral virulence. The binding of virus by Lens culinaris lectin was associated with the elution rate of the virus from chicken erythrocytes. Strains that elute rapidly from chicken erythrocytes were not bound by Lens culinaris lectin. The sugar alpha-D-N-acetylglucosamine inhibited the adsorption of Lens culinaris lectin to the strains that were "slow eluters" from chicken erythrocytes.

Many Newcastle disease virus strains are composed of several biotypes which coexist in the wild and in laboratory cultures. We have studied some of the phenotypic and genotypic properties of 6 virus clones from the coexisting biotypes of the Hickman strain of Newcastle disease virus. These clones were readily distinguishable from the parent virus strain and from each other by their RNA fingerprints. Fingerprints of the most virulent clones (Hi/LC, Hi/MC, and Hi/LR) contained 61% to 77% of the oligoribonucleotides present in the fingerprint of the Hickman parent strain. None of the clones killed chickens as rapidly as did the parent strain, although some clones killed embryonating eggs as rapidly as did the parent strain.

In an attempt to demonstrate differences in antibody prevalence between free-living and institutionalized children, antibodies to Cytomegalovirus (CMV), Epstein-Barr virus (EBV), and Herpesvirus hominis (HVH), types 1 and 2, were assayed in 123 children. The children comprised three groups consisting of 41 institutionalized patients with Down's syndrome (all non-disjunctive trisomy-G karyotype and equal numbers of age-, sex-, and race-matched non-mongoloid institutionalized subjects and non-institutionalized normal controls. CMV antibody titer values were statistically similar in the three groups. However, fewer mongoloids (21.9%) were seropositive than other institutionalized retardates (39.0%) and normal control subjects (43.9%). Antibody titer values to EBV were also similar; however, in comparison to the other groups, significantly more mongoloids were seropositive at younger ages. More mongoloids were seropositive to HVH-1 and had higher antibody titers than the other two groups. Antibody to HVH-2 was more prevalent in institutionalized subjects, 85.4% in mongoloids and 65.8% in other institutionalized retardates, than in normal non-institutionalized children (26.8%).

Macromolecules present in low concentrations in xylem fluid of Medicago sativa L. var DuPuits will increase the resistance to xylem liquid flow. This increase in resistance was found to be reversible by backflushing the xylem. Autoradiography showed that very large molecules do not pass through pit membrane pores. A comparison of pit membrane pore sizes to molecule sizes suggests that increased resistance to xylem flow is a result of plugging pit membrane pores. It was also found that pit membranes located in two parts of the plant differ in the apparent diameter of their pores and, thus, in their susceptibility to plugging by macromolecules. Macromolecules in xylem fluid may result from hostparasite interactions and may play a significant role in the outcome of the interaction.

Human stromal (fibroblast) cultures were established from random, normal corneas obtained from the International Eye Bank in Baltimore. Cultures were assessed for the expression of Class I, Class II, monocyte/granulocyte and T-cell antigens before and after treatment with gamma or alpha interferon (IFN), interleukin 2, and 4 beta-phorbol 12 beta-myristate 13 alpha-acetate (PMA). Class I (B2 microglobulin) and monocyte/granulocyte (Leu M-1) antigens were evident before induction, natural killer cell (Leu 7) antigens were transiently expressed, and Class II (HLA-DR, Leu 10) antigens were not expressed until after induction with gamma IFN. PMA reduced the numbers of cells positive for Leu M-1 while alpha IFN and interleukin 2 had no effect on antigen expression. Kinetic studies of HLA-DR induction indicated that as little as 12 hours exposure to gamma IFN was sufficient to initiate induction and that 30% of the population was still expressing HLA-DR 7 days after removal of gamma IFN. The inducible expression of Class II antigens following lymphokine exposure may play a critical role in rejection of allografted corneas.

Genomic fragments coding for sequences expressed as abundant mRNA in female Drosophila melanogaster were isolated from a lambda library. Hybridization of these clones to polytene chromosomes. in situ, identified four which mapped to X chromosomal region 9A to 9B, the locus for yolk proteins 1 and 2 (Ypl,2) and two which mapped to 12A6-7 to 12D3, the locus for Yp3. These clones were mapped with restriction enzymes, and the coding regions and regions of homology determined by Southern blots probed with cDNA, 5'-end-labelled RNA and nick-translated DNA. Heteroduplex and R-loop mapping confirmed that three of the clones carried two genes separated by about 1.4 kb and oriented in opposite directions. Southern blots probed with cDNA made from alkali-hydrolyzed RNA showed that these genes had their 5' ends next to each other. All 3 genes show homology to each other and have a main coding region of about 1.3 kb, the approximate size for the mRNAs.

Two cultures of the CG179 strain of Newcastle disease virus were maintained apart in two laboratories for over 30 years. One culture had been passaged 45 times through embryonated chicken eggs, yet this virus had the same virulence, thermostability of hemagglutinin, plaque types, and RNA fingerprint as a culture lyophilized in 1948. The genetic stability observed here has not been reported for strains containing both red and clear plaques and may occur only in strains like CG179 that do not have red plaques.