Impaired cortisol awakening response in eating disorder women with childhood trauma exposure: evidence for a dose-dependent effect of the traumatic load.

BACKGROUND: Childhood trauma is a non specific risk factor for adult eating disorders (ED), and the hypothalamic-pituitary-adrenal (HPA) axis seems to mediate such a risk. Here we explored the impact of different types of childhood trauma and of traumatic load on the cortisol awakening response (CAR) of women with anorexia nervosa (AN) or bulimia nervosa (BN). METHODS: Saliva samples were collected at awakening and after 15, 30, 60 min to measure cortisol levels by 121 women (44 AN patients, 36 BN patients and 41 healthy women). Participants filled in the Childhood Trauma Questionnaire. RESULTS: AN and BN patients with childhood maltreatment exhibited an attenuated CAR compared with non-maltreated ones. In the whole ED patient group, the CAR showed a progressive impairment with the increasing number of reported trauma types. Although significant negative correlations emerged between the type or the number of traumas and the CAR, only the number of traumas remained significantly associated with the CAR in a stepwise multiple regression analysis. CONCLUSIONS: Present findings confirm that childhood trauma is associated with an impaired CAR in adult AN and BN patients and demonstrate for the first time a negative dose-dependent effect of the traumatic load on HPA axis activity.

Is dialdehyde starch a valuable cross-linking agent for collagen/elastin based materials?

Collagen and elastin are the main structural proteins in mammal bodies. They provide mechanical support, strength, and elasticity to various organs and tissues, e.g. skin, tendons, arteries, and bones. They are readily available, biodegradable, biocompatible and they stimulate cell growth. The physicochemical properties of collagen and elastin-based materials can be modified by cross-linking. Glutaraldehyde is one of the most efficient cross-linking agents. However, the unreacted molecules can be released from the material and cause cytotoxic reactions. Thus, the aim of our work was to investigate the influence of a safer, macromolecular cross-linking agent--dialdehyde starch (DAS). The properties of hydrogels based on collagen/elastin mixtures (95/5, 90/10) containing 5 and 10% of DAS and neutralized via dialysis against deionized water were tested. The homogenous, transparent, stiff hydrogels were obtained. The DAS addition causes the formation of intermolecular cross-linking bonds but does not affect the secondary structure of the proteins. As a result, the thermal stability, mechanical strength, and, surprisingly, swelling ability increased. At the same time, the surface properties test and in vitro study show that the materials are attractive for 3T3 cells. Moreover, the materials containing 10% of DAS are more resistant to enzymatic degradation.

Asymmetry of salivary cortisol and α-amylase responses to psychosocial stress in anorexia nervosa but not in bulimia nervosa.

BACKGROUND: The stress response involves the activation of the hypothalamic-pituitary-adrenal (HPA) axis and the sympathetic nervous system (SNS). As a role for stress in determining of the onset and the natural course of eating disorders (EDs) has been proposed, the study of the psychobiology of the stress response in patients with anorexia nervosa (AN) and bulimia nervosa (BN) should be helpful in understanding the pathophysiology of these disorders. The two neurobiological components of the stress response can be easily explored in humans by the measurement of salivary cortisol and α-amylase response to a stressor. Therefore, we assessed salivary cortisol and α-amylase responses to the Trier Social Stress Test (TSST) in symptomatic patients with AN and BN compared to healthy controls. METHOD: Seven AN women, eight BN women and eight age-matched healthy females underwent the TSST between 1530 and 1700 h. Salivary cortisol and α-amylase levels were measured by an enzyme-linked immunosorbent assay (ELISA). RESULTS: Compared to healthy women, AN patients showed a normal cortisol response to the TSST, although this occurred at significantly increased hormone levels, and an almost complete absence of response of α-amylase. BN women, however, exhibited enhanced pre-stress levels of salivary α-amylase but a normal response of the enzyme and cortisol to the TSST. CONCLUSIONS: These findings demonstrate, for the first time, the occurrence of an asymmetry between the HPA axis and SNS components of the stress response in the acute phase of AN but not in BN. The pathophysiological significance of this asymmetry remains to be determined.

Collagen/elastin hydrogels cross-linked by squaric acid.

Hydrogels based on collagen and elastin are very valuable materials for medicine and tissue engineering. They are biocompatible; however their mechanical properties and resistance for enzymatic degradation need to be improved by cross-linking. Up to this point many reagents have been tested but more secure reactants are still sought. Squaric acid (SqAc), 3,4-dihydroxy 3-cyclobutene 1,2-dione, is a strong, cyclic acid, which reacts easily with amine groups. The properties of hydrogels based on collagen/elastin mixtures (95/5, 90/10) containing 5%, 10% and 20% of SqAc and neutralized via dialysis against deionized water were tested. Cross-linked, 3-D, transparent hydrogels were created. The cross-linked materials are stiffer and more resistant to enzymatic degradation than those that are unmodified. The pore size, swelling ability and surface polarity are reduced due to 5% and 10% of SqAc addition. At the same time, the cellular response is not significantly affected by the cross-linking. Therefore, squaric acid would be regarded as a safe, effective cross-linking agent.

Research on possible medical use of silk produced by caddisfly larvae of Hydropsyche angustipennis (Trichoptera, Insecta).

Silk products are used in medicine as biomaterials, and are particularly promising as scaffolds in tissue engineering. To date only silkworm and spider silk medical potential has been evaluated, whereas the possible application of the material spun by caddisflies in wet environment has not been examined. Biomedical application of every natural material requires biocompatibility testing and evaluation of unique microbiological and mechanical properties. This article focuses on silk fibers formed in caddisflies cocoons of Hydropsyche angustipennis (Insecta, Trichoptera) larvae. Preliminary biological evaluation shows that trichopteran silk is not cytotoxic to human cells. Caddisfly silk itself does not possess antiseptic properties and thus sterilization is indispensable for its application in medicine. Among tested methods of sterilization and disinfection only thermal methods (tyndallization and autoclaving) enabled complete eradication of bacteria and gave fully sterile material. Caddisfly silk appeared to be resistant to high temperature. Fully sterile fibers can be stored without a loss of breaking force and tensile strength. Our work shows that trichopteran silk has a significant potential to be used as a biomaterial.

Physical illness and schizophrenia: a review of the literature.

OBJECTIVE: The lifespan of people with schizophrenia is shortened compared to the general population. We reviewed the literature on comorbid physical diseases in schizophrenia to provide a basis for initiatives to fight this unacceptable situation. METHOD: We searched MEDLINE (1966 - May 2006) combining the MeSH term of schizophrenia with the 23 MeSH terms of general physical disease categories to identify relevant epidemiological studies. RESULTS: A total of 44 202 abstracts were screened. People with schizophrenia have higher prevalences of HIV infection and hepatitis, osteoporosis, altered pain sensitivity, sexual dysfunction, obstetric complications, cardiovascular diseases, overweight, diabetes, dental problems, and polydipsia than the general population. Rheumatoid arthritis and cancer may occur less frequently than in the general population. Eighty-six per cent of the studies came from industrialized countries limiting the generalizability of the findings. CONCLUSION: The increased frequency of physical diseases in schizophrenia might be on account of factors related to schizophrenia and its treatment, but undoubtedly also results from the unsatisfactory organization of health services, from the attitudes of medical doctors, and the social stigma ascribed to the schizophrenic patients.