Barbed suture vs conventional tenorrhaphy: biomechanical analysis in an animal model.

BACKGROUND: The advantages of barbed suture for tendon repair could be to eliminate the need for a knot and to better distribute the load throughout the tendon so as to reduce the deformation at the repair site. The purpose of this study was to evaluate the breaking force and the repair site deformation of a new barbed tenorrhaphy technique in an animal model. MATERIALS AND METHODS: Sixty porcine flexor tendons were divided randomly into three groups and repaired with one of the following techniques: a new 4-strand barbed technique using 2/0 polypropylene Quill™ SRS or 2/0 polydioxanone Quill™ SRS and a modified Kessler technique using 3/0 prolene. All tendons underwent mechanical testing to assess the 2-mm gap formation force, the breaking force and the mode of failure. The percentage change in tendon cross-sectional area before and after repair was calculated. RESULTS: The two-sample Student t-test demonstrated a significant increase in 2-mm gap formation force and in breaking force with barbed sutures, independently from suture material, when compared to traditional Kessler suture. Concerning the tendon profile, we registered less bunching at the repair site in the two barbed groups compared with the Kessler group. CONCLUSIONS: This study confirms the promising results achieved in previous ex vivo studies about the use of barbed suture in flexor tendon repair. In our animal model, tenorrhaphy with Quill™ SRS suture guarantees a breaking force of repair that exceeds the 40-50 N suggested as sufficient to initiate early active motion, and a smoother profile at the repair site. LEVEL OF EVIDENCE: Not applicable

A model of management academics' intentions to influence values

Business schools face increased criticism for failing in the teaching of management studies to nurture their students’ values. Assuming that individual academics play an important role in shaping the value-related influence of business schools, I model management academics’ intentions to influence values. The suggested model encompasses academics’ economic and social values as internal variables, as well as perceived support for attempting to influence values and academic tenure as social and structural variables. A test with empirical data from 1,254 management academics worldwide reveals that perceived external support is most relevant for explaining intentions. Moreover, academics’ social values, but not their economic ones, contribute to an explanation of their intentions to influence values. The results reveal how important it is for academics to believe that their colleagues, higher education institutions, and other stakeholders support their value-related behavioral intentions

Consumer perceptions of internet retail service quality.

The purpose of this manuscript is to explore consumers\u27 perceptions of Internet retail service quality. This is accomplished via two studies. Study 1 utilizes qualitative depth interviews to identify five dimensions important to consumers in their assessment of the quality of Internet retailers. These are termed performance (how well an online retailer does in terms of meeting expectations regarding order fulfillment), access (Internet retailer\u27s ability to provide a variety of products from anywhere in the world), security (relating to perceptions of trust in the online retailer\u27s integrity regarding financial and privacy issues), sensation (interactive features of the e-retailer\u27s Web site) and information (quantity and credibility of information provider by the online retailer). Study 2 quantifies the five dimensions using multi-item scales, and conducts a survey to assess the reliability and validity (convergent, discriminant, and nomological) of these dimensions. Theoretical and managerial implications of the results are also discussed

Environmental and societal positioning as sources of competitive advantage in an agricultural firm.

This research seeks to ascertain whether an agricultural firm\u27s social and environmental positioning affects consumers\u27 perceptions of the attributes of its products. Results showed that companies that are perceived to be more socially and environmentally conscious received better ratings for their produce in terms of quality and freshness. In addition, consumers reported that they would be willing to pay more for food grown by socially and environmentally conscious firms

EFFECTS OF VITAMIN B6 DEFICIENCY ON LYMPHOID TISSUES AND HUMORAL IMMUNE RESPONSE IN RATS (IMMUNITY, PYRIDOXINE)

The influence of vitamin B(,6) deficiency on lymphoid tissues and humoral immune response in rats was assessed in two experiments. In experiment I effects of vitamin B(,6) deficiency on humoral immune response and morphological changes of sensitized lymphoid tissues were studied in growing rats. Male weanling rats (Sprague-Dawley) were divided into three treatment groups: control, restricted control and vitamin B(,6) deficient. Animals in control and vitamin B(,6) deficient groups were fed for 8 wk ad libitum a basal diet supplemented with 7 or 0 mg pyridoxine-HCl(PN-HCl)/kg, respectively. The restricted control group was fed the control diet (7 mg PN-HCl/kg) but restricted in amount to that consumed by the vitamin B(,6) deficient group on the previous day. At 7 wk, formalinized Streptococcus mutans was administered intraperitoneally. Antibody titers against S. mutans, measured by microagglutination test at 9 wk, were significantly lowered by vitamin B(,6) deficiency. Activities of IgM and IgG antibody were low in the deficient group and lymphocyte depletion was observed in thymus and paracortical regions of ileic lymph nodes. Immunized deficient rats showed no germinal centers or poorly developed ones in lymph nodes indicating their inability to respond normally to an antigenic stimulation. In experiment 2, the effect of maternal vitamin B(,6) deficiency on the developing immune system in rats was studied. Female rats (Sprague-Dawley) were fed diets containing 7, 0.6, 0, or 7 mg pyridoxine-HCl (PN-HCl)/kg during gestation and 7, 0.6, 7, or 0 mg PN-HCl/kg during lactation (groups C, MGL, DG and DL). Severe deficiency during gestation adversely affected thymus and spleen sizes of 2-day-old pups. Marginal restriction of vitamin B(,6) imposed on dams throughout gestation and lactation resulted in extremely low weights of thymus and spleen in 20-day-old pups. Severe restriction of vitamin B(,6) during lactation affected spleen weight more than thymus. After weaning, pups in groups, C, MGL, DG, and DL were fed diets containing 7, 0.6, 7, and 7 mg PN-HCl/kg, respectively. On day 42, pups of the MGL group had smaller thymuses and spleens. After 3 or 6 wk of vitamin B(,6) supplementation, weights of lymphoid tissues were restored to controls but the functional ability of ileic lymph nodes to respond to an antigenic stimulation remained impaired. Dietary restriction of vitamin B(,6) during either gestation or lactation did not significantly affect the humoral immune response of progeny. However, marginal restriction of vitamin B(,6) throughout gestation and lactation of dams and during a 21-day postweaning period of their pups resulted in depressed antibody titers of pups immunized with S. mutans