[Consultation/liaison addiction medicine: Tools and specificities]. / L'addictologie de liaison : outils et spécificités.

Since the 1970s, the concept of "consultation/liaison (CL) psychiatry" has pertained to specialized mobile teams which meet inpatients hospitalized in non-psychiatric settings to offer them on-the-spot psychiatric assessment, treatment, and, if needed, adequate referral. Since the birth of CL psychiatry, a long set of theoretical books and articles has aimed at integrating CL psychiatry into the wider scope of psychosomatic medicine. In the year 2000, a circular issued by the Health Ministry defined the organization of "CL addiction services" in France. Official CL addiction teams are named "Équipes de Liaison et de Soins en Addictologie" (ELSAs) which are separated from CL psychiatry units. Though this separation can be questioned, it actually emphasizes that the work provided by CL addiction teams has some very specific features. The daily practice of ELSAs somewhat differs from that of psychiatric CL teams. Addictive behaviors often result from progressive substance misuse. In this respect, the ELSAs' practice frequently involves screening, brief intervention, and referral to treatment (SBIRT) interventions, which are rather specific of addiction medicine and consist more of prevention interventions than actual addiction treatment. Moreover, for patients with characterized substance use disorders substantial skills in motivational interviewing are required in ELSA consultations. Though motivational interviewing is not specific to addiction medicine, its regular use is uncommon for other liaison teams in France. Furthermore, substance misuse can induce many types of acute or delayed substance-specific medical consequences. These consequences are often poorly known and thus poorly explored by physicians of other specialties. ELSAs have therefore the role of advising their colleagues for a personalized somatic screening among patients with substance misuse. In this respect, the service undertaken by ELSAs is not only based on relational skills but also comprises a somatic expertise. This specificity differs from CL psychiatry. Moreover, several recent studies have shown that in some cases it was useful to extend liaison interventions for addiction into outpatient consultations that are directly integrated in the consultation units of certain specialties (e.g., hepatology, emergency, or oncology). Such a partnership can substantially enhance patients' motivation and addiction outcome. This specificity is also hardly transposable in CL psychiatry. In France, addiction medicine is an inter-specialty that is not fully-integrated into psychiatry. This separation is also applied for CL services which emphasizes real differences in the daily practices and in intervention frameworks. Regardless, CL psychiatry units and ELSAs share many other features and exhibit important overlaps in terms of targeted populations and overall missions. These overlaps are important to conjointly address, with the aim to offer integrated and collaborative services, within the hospital settings of other medical specialties.

Growth characteristics of human glioma-derived and fetal neural cells in culture.

Growth characteristics of human fetal neural cells (CH) and human glioblastoma multiforme-derived cells (12-18) in culture were compared. Cells were grown to confluent densities of 38,000 to 42,500 cells/cm2 for CH and 85,800 to 87,100 for 12-18. Population doubling times were 40.0 +/- 5.1 hr and 66.5 +/- 9.8 hr for CH and 12-18 cells, respectively. The mean DNA content per cell of the glioma-derived cells was twice that of the fetal brain cells at sparse, log, and confluent cell densities. High concentrations (40%) of serum in growth medium increased DNA contents in confluent CH, but not 12-18, cells. The amount of protein per cell also was consistently higher in glioma cells than CH cells, but, as cell densities increased, protein contents decreased for both: 1200 to 700 pg/cell in glioma cells, and 840 to 560 pg/cell in CH cells. In each cell line, initial rates of [3H]ThdR incorporation into TCA precipitable material decreased as cell density increased, but confluent glioma-derived cells incorporated 10 times more [3H]ThdR than confluent fetal cells. Almost all CH cells had a normal diploid chromosome number of 46. A histogram showing the relative frequencies of chromosome numbers of glioma-derived cells had peaks of 52, 79, and 105 chromosomes per metaphase, indicating a haploid number of 26 for most cells. Lengths of cell cycle phases, determined using autoradiographic techniques, indicate that glioma-derived cells had a longer generation time and S period than fetal neural cells. These data demonstrate several biological differences between glioblastoma-derived cells and non-neoplastic fetal neural cells, indicating that this system is of potential value for comparative studies on growth control and contact inhibition.

Resistance to caffeine of mouse fibroblasts after acquisition of an infinite division potential.

Mouse fibroblasts can easily become permanent cell lines when subcultivated in vitro. It has been previously questioned whether the cells that establish in culture originate in vitro or are already present in the primary culture. We have found that cells from the primary culture do not survive in the presence of caffeine but that after establishment the cells become resistant to the drug. The results suggest that the cells with an infinite growth potential are not present in the primary culture.

Spontaneous structural changes in DNA during fibroblast aging and the establishment process in vitro.

The molecular weight of single-stranded DNA isolated from human fibroblasts decreased in phase III by comparison with phase II. Mouse fibroblast DNA isolated during the growth crisis had a decreased molecular weight compared to the initial DNA. Established mouse cells recovered this high molecular weight DNA. Cells treated with caffeine during the growth crisis did not survive while established cells were resistant to the same conditions of caffeine treatment. A DNA repair process may play a role in establishing a permanent cell line.

Changes in DNA alkali-sensitive sites during senescence and establishment of fibroblasts in vitro.

DNA molecular weight was studied in human embryonic and mouse newborn lung fibroblasts in vitro at different passages of the culture using alkaline and neutral sucrose gradient techniques. Reduction of molecular weight of single-stranded DNA due to alkaline-sensitive sites appeared spontaneously during the growth decline of the mouse cells. These changes disappeared when the mouse fibroblasts became a permanent cell line. At the end of phase II of the human fibroblasts, the molecular weight of single-stranded DNA also decreased, followed by the restitution of some high molecular weight DNA in the ultimate passages. When treated with 1 mM caffeine, the mouse fibroblasts during growth crisis did not survive, while cells of the established line resisted. Thus it might be possible that a DNA repair process was involved in the recovery of the mouse fibroblasts. Furthermore, results favor the hypothesis that the cells that become established are not present in the primary culture but originate in vitro.

Effect of low dose rate irradiation on the division potential of cells in vitro. VI. Changes in DNA and in radiosensitivity during aging of human fobroblasts.

The sensitivity to low dose rate ionizing radiation increases progressively through the lifespan of human embryonic lung fibroblasts. There is also an increase in the number of alkali-sensitive sites leading to an increase in single-strand breaks and in DNA with low molecular weight during cell lysis. These DNA changes become pronounced at the very end of the lifespan. The correlation between aging, increased radiosensitivity and accumulation of DNA damage is discussed.

Effects of PR toxin on liver cells in culture.

We studied the effects on liver cells in culture of PR toxin, a substance produced from Penicillium roqueforti. PR toxin displayed cytotoxicity which increased as a function of its concentration but the form of such toxicity differed, depending on the toxin's concentration. Thus, cells only underwent quick retraction and intensive vacuolization when treated with low drug concentrations, and they came away from the substrate easily under these conditions. By contrast, the major events observed in the case of high concentrations were loss of structure of the nuclei and strong adhesiveness of dead cells to the support. PR toxin already inhibited cell multiplication at low concentrations and became toxic when the concentration was raised; growth inhibition decreased but the toxic effect increased when cells passed from the exponential growth phase to a phase of slower growth. PR toxin inhibited tritiated precursor incorporation into DNA, RNA and proteins in a similar time and concentration-dependent manner. Inhibition of DNA synthesis persisted even after removal of the drug from the medium.