[Grief, evolution of new definitions]. / Deuil, évolution conceptuelle et nouvelles définitions.

The concept of pathological grief is a controversial issue. Bereavement is a universal experience, and its association with excess morbidity and mortality is well established. Complicated grief is a process that by its length or intensity is considered pathological but not considered as a distinct mental disorder in the present international classifications: ICD-10 and DSM-IV-TR. For some individuals, if intense grief persists, is distressing and disabling, and may meet criteria as a distinct mental disorder. This definition evolved with the implementation of a proposed criteria for a persistent complex bereavement disorder in the section of "condition of further study"s of the new DSM-5 after the debate raised by the proposition of several authors to include a distinct mental disorder. We tried to illustrate that complex question with a non exhaustive review and with a case report of a clinical situation of a female that was treated in a crisis center in Geneva, following the sudden death of her husband.

Brillouin spectroscopy: a new tool to decipher viscoelastic properties of biological scaffold functionalized with nanoscale films.

BACKGROUND: In tissue engineering, the endothelialization of vascular scaffold can be a crucial step to improve graft patency. A functional cellularization requires coating surfaces. Since 2003, our group used polyelectrolyte multilayer films (PEMFs) made of poly(allylamine hydrochloride) and polystyren sulfonate to coat luminal surface of blood vessel. Previous results showed that PEMFs have remarkable effect on cellular behavior: adhesion, proliferation, differentiation. However, no method seems adapted for in vitro measurement of the viscoelastic shift after PEMFs buildup. OBJECTIVE: In this present work, we proposed to use a new analytical method based on Brillouin spectroscopy (BS) to investigate the influence PEMFs coating on vessel intrinsic viscoelasticy. METHODS: On human umbilical arteries and rabbit vessels, PEMFs were buildup and the luminal surfaces viscoelasticy were measuring by BS. RESULTS: It seems that these films do not alter dynamic functionality and BS could be an interesting method for understanding the role of the tissue architecture, the interrelation between the different structures constituting the wall and the influence of this architecture on the tissue behavior, especially with the characterized components of the different vascular wall. CONCLUSION: The ability of BS to characterize biological samples opens potential applications in tissue engineering field, especially as a tool for a better understanding of vascular diseases.

Reversing charges or how to improve Wharton's jelly mesenchymal stem cells culture on polyelectrolyte multilayer films.

BACKGROUND: Polyelectrolyte multilayer (PEMs) films made of poly(allylamine hydrochloride) (PAH) as polycation and poly(styrene sulfonate) (PSS) as polyanion, with a PAH ending layer, can be used as a coating in order to improve the anti-thrombogenicity and patency of vascular grafts in vascular engineering field. They induce strong adhesion of mature endothelial cells on glass, expanded polytetrafluoroethylene and cryopreserved arteries. Despite their outstanding effect on mature and progenitor endothelial cells, PEMs ending with PAH showed a poor outcome on Wharton's jelly mesenchymal stem cells (WJ-MSCs) culture. OBJECTIVE: The aim of this work was to examine the influence of the ending charge of PEMs on WJ-MSCs behavior. METHODS: WJ-MSCs amplified until the 3rd passage were seeded and cultured on (PAH-PSS)3-PAH and on (PAH-PSS)4 coated glass for 10 days. Stem cell phenotype was checked by flow cytometry and cell morphology was followed by bright field microscopy. RESULTS: Flow cytometry analysis showed that WJ-MSCs were positive for MSC's markers CD73, CD90 and CD105 and negative for hematopoietic markers CD34 and CD45. Light microscopy showed development of nodule-like structures after 10 days of culture on (PAH-PSS)3-PAH, which resulted in a disturbance of cell monolayer. Whereas WJ-MSCs cultured on (PAH-PSS)4 ending with PSS showed a normal cell growth like on collagen and reached confluence after 10 days. CONCLUSION: The culture surface seems to have a determining role in WJ-MSC's "spatial" behavior, which could be considered in the field of tissue engineering.