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BACKGROUND: Little information exists on the perceptions of psychiatrists regarding the implementation and various impacts of the consultation-liaison model. This model has been used in Quebec (Canada) through the function of specialist respondent-psychiatrists (SRP) since 2009. This study assessed the main activities, barriers or facilitators, and impact of SRP in adult and child-adolescent psychiatry on the capacity of service providers in primary care and youth centers to treat patients with mental health disorders (MHD). METHODS: Data included 126 self-administered questionnaires from SRP and semi-structured interviews from 48 SRP managers. Mixed methods were used, with qualitative findings from managers complementing the SRP survey. Comparative analyses of SRP responses in adult versus child-adolescent psychiatry were also conducted. RESULTS: Psychiatrists dedicated a median 24.12 h/month to the SRP function, mainly involving case discussions with primary care teams or youth centers. They were confident about the level of support they provided and satisfied with their influence in clinical decision-making, but less satisfied with the support provided by their organizations. SRP evaluated their impacts on clinical practice as moderate, particularly among general practitioners (GP). SRP working in child-adolescent psychiatry were more comfortable, motivated, and positive about their overall performance and impact than in adult psychiatry. Organizational barriers (e.g. team instability) were most prevalent, followed by system-level factors (e.g. network size and complexity, lack of resources, model inflexibility) and individual factors (e.g. GP reluctance to treat patients with MHD). Organizational facilitators included support from family medicine group directors, collaboration with university family medicine groups and coordination by liaison nurses; at the system level, pre-existing relationships and working in the same institution; while individual-level facilitators included SRP personality and strong organizational support. CONCLUSION: Quebec SRP were implemented sparingly in family medicine groups and youth centers, while SRP viewed their overall impact as moderate. Results were more positive in child-adolescent psychiatry than in adult psychiatry. Increased support for the SRP function, adapting the model to GP in need of more direct support, and resolving key system issues may improve SRP effectiveness in terms of team stability, coordination among providers, access to MH services and readiness to implement innovations.

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OBJECTIVE: To evaluate the potential of (18)F-fluoro-deoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) for early therapeutic intervention in patients with probable or confirmed tuberculosis (TB). METHODS: Twenty-one consecutive human immunodeficiency virus negative patients were prospectively included. All patients underwent (18)F-FDG PET/CT before and after 1 month of anti-tuberculosis treatment. The maximum standardised uptake value (SUV(max)) of the most (18)F-FDG avid lesions was recorded. RESULTS: The median age of patients was 36 years (range 18-84); 33.3% were male, 80.9% were born in endemic countries, and 23.8% had a past history of TB. TB was confirmed on culture in 8, on histology in 9 and on the basis of clinical symptoms in 4 patients. (18)F-FDG PET/CT detected active pulmonary TB (n = 1), extra-pulmonary (n = 10) or both (n = 10). The second (18)F-FDG PET/CT showed reduced radiotracer uptake intensity in 19 of 21 patients, with a median percentage decrease of SUV(max) of 31% (range 2-84). Two patients showed no improvement. TB was ruled out in one patient during follow-up; the final diagnosis was a non-Hodgkin's lymphoma. The other patient was smear-positive for 3 months. CONCLUSION: (18)F-FDG PET/CT allows an easy evaluation of early therapeutic response in patients with TB, particularly extra-pulmonary TB.

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BACKGROUND/AIM: Although the role of bacteria in the etiology of periodontitis is well established, it has been suggested that herpetic viruses could contribute to the initiation and progression of this disease. The aim of this study was to determine the prevalence of human cytomegalovirus (HCMV), Epstein-Barr virus (EBV) and herpes simplex virus (HSV) in gingival crevicular fluid (GCF) samples obtained from periodontally healthy, gingivitis and periodontitis patients. In addition, the effect of periodontal treatment (scaling and root planing) on the persistence of herpetic viruses was evaluated in a sub-group of patients suffering from chronic periodontitis. METHODS: The presence of viruses in GCF samples was assessed by a nested PCR amplification technique. The persistence of viruses in periodontal sites was evaluated following a scaling and root planing therapy. RESULTS: A statistically significant higher prevalence of HCMV was observed in periodontitis patients as compared to healthy control subjects (35 vs. 8%, respectively; P = 0.0377). A trend for a higher prevalence of HSV was also noted in the periodontitis group, in comparison with healthy control subjects. In addition, a higher prevalence of HCMV was associated with deep periodontal pockets in subjects suffering from periodontitis. In the sub-group of periodontitis patients, periodontal therapy resulted in the elimination (HCMV and EBV) or reduction (HSV) of the herpetic viruses. CONCLUSIONS: This study showed that the prevalence of HCMV and HSV viruses in GCF is higher in patients suffering from periodontitis compared to periodontally healthy subjects, and that the prevalence of HCMV is higher in deep periodontal pockets. It also brought evidences that periodontal therapy may be associated with virus elimination in diseased sites.

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The bone morphogenetic proteins (BMPs) are cytokines of the transforming growth factor beta family. Some BMPs such as BMP-2 and BMP-7 play a major role in the development of the skeleton and the maintenance of homeostasis during bone remodelling. To date, only BMP-2 and BMP-7 have been approved by the Food and Drug Administration for specific orthopaedic applications. However, due to BMP cost, peptides derived from their knuckle epitope with osteogenic properties have been developed. BMPs are involved in many other biological events, including embryogenesis, angiogenesis and cancer. BMPs therefore have great biomedical potential as osteogenic factors and as anti-cancer agents. This review focuses on the use of BMPs and their derived peptides in biomedical delivery systems and gene therapy.

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The goal of this study was to optimize key processes in recreating functional and viable palatal mucosa-like tissue that would be easy to handle and would promote wound healing. Normal human gingival fibroblasts and epithelial cells and a clinically useful biomaterial, CollaTape, were used. Structural and ultrastructural analyses showed that the gingival fibroblasts and epithelial cells adhered to the biomaterial and proliferated. Following a 6-day culture, using 10(5) fibroblasts and 10(6) epithelial cells, a well-organized palatal mucosa-like tissue was engineered. The engineered epithelium displayed various layers, including a stratum corneum, and contained cytokeratin 16-positive cells located in the supra-basal layer. This palatal mucosa-like engineered tissue was designed to meet a variety of surgical needs. The biodegradable collagen membrane (CollaTape) contributed to the flexibility of the engineered tissue. This engineered innovative tissue may contribute to the reconstruction of oral soft-tissue defects secondary to trauma, congenital defects, and acquired diseases.

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More than a century after the initial description of muscular dystrophy, no curative treatment is currently available. To date, clinical trials with myogenic stem cell transplantation have met with only modest success. There are multiple factors behind these failures, yet they provide powerful insights for improvement. In this chapter, we review the different myogenic stem cell populations that have been reported to be potential vectors for the treatment of myopathies in a context of regenerative medicine.

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The intrinsic surface activity of the contractile protein actin has been determined from surface tension measurements using the Wilhelmy hanging-plate method. Actin, a very soluble protein, moves from the subphase to the air-water interface to make a film. In the absence of magnesium, actin is monomeric and is known as G-actin. During the compression the monomers change their conformation or orientation at the interface and they are then pushed reversibly into the subphase upon further compression. No collapse occurs. Actin monomers in the presence of magnesium become activated; at concentrations greater than some critical value, actin polymerizes to form filaments of F-actin. The actin filaments have a higher surface activity than the actin monomers either because they are more hydrophobic or because F-actin, a rigid polymer, is much more efficient at creating excluded volume. The actin filaments then form a rigid film at the interface that collapses when the surface area is decreased. At less than the critical concentration, the actin monomers are present in the subphase in their activated form. However, their concentration increases at the interface during film compression until the critical concentration is reached. The surface pressure isotherm in this case has the characteristics of a G-actin film at the beginning of the compression and of an F-actin film at the end of the compression process.

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Porphyromonas gingivalis, a bacterium associated with active chronic periodontitis lesions, produces several proteolytic enzymes that are thought to be involved in host colonization, perturbation of the immune system, and tissue destruction. The aim of the present study was to investigate the contribution of Arg- and Lys-gingipains produced by P. gingivalis to its growth. Although all of the proteins studied were degraded by P. gingivalis, only human serum albumin and transferrin supported growth during serial transfers in a chemically defined medium (CDM). Growth studies with site-directed gingipain-deficient mutants of P. gingivalis revealed that inactivation of both gingipains prevents growth, whereas inactivation of either Arg- or Lys-gingipain activity extended the doubling times to 33 or 13 h, respectively, compared to 9 h for the parent strain. Growth of the mutants and the parent strain was similar when the CDM was supplemented with a protein hydrolysate instead of human serum albumin. Incubation of resting P. gingivalis ATCC 33277 cells with fluorophore-labeled albumin indicated that the proteolytic fragments generated by the gingipains were internalized by the bacterial cells. Internalization of fluorophore-labeled albumin fragments was reduced or completely inhibited in the proteinase-deficient mutants. Interestingly, gingival crevicular fluid samples from diseased periodontal sites contained low-molecular-mass albumin fragments, whereas samples from healthy sites did not. The critical role of proteinases in the growth of P. gingivalis was further investigated using specific Arg- and Lys-gingipain inhibitors. Adding the inhibitors to CDM containing albumin revealed that leupeptin (Arg-gingipain A and B inhibitor) was more efficient at inhibiting growth than cathepsin B inhibitor II (Lys-gingipain inhibitor). Our study suggests that Arg-gingipains and, to a lesser extent, Lys-gingipain play an important role in the growth of P. gingivalis in a defined medium containing a human protein as the sole carbon and nitrogen source.

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Elastic fibers form a complex network that contributes to the elasticity of connective tissues. Alterations in the elastic fiber network are involved in several disease affecting organs in which compliance of the connective tissue is essential: skin, main vasculature, lung, joints, muscle, and ligament. The aim of our work was to study the deposition, maturation, and organization of elastic fiber components in a dermal equivalent model consisting of collagen-GAG-chitosan seeded with fibroblasts. The influence of keratinocytes was studied in parallel, thus constituting a skin equivalent model. These models were examined by transmission electron microscopy (TEM) and by immunohistochemistry to determine the staining patterns of fibrillin-1 and elastin proteins representative of the microfibrillar framework and of the elastic fibers, respectively. After 2 mo of fibroblast culture in the dermal equivalent, elastin was undetectable, whereas fibrillin-1 staining was weak and microfibrils were infrequently observed by TEM. In the skin equivalent, fibrillin-1 and elastin were detected by immunostaining 15 d after epidermization and TEM revealed the typical structure and organization of the elastic network in the dermis, with elastin deposition on the microfibrillar scaffold. This in vitro skin equivalent model is to our knowledge the first in which elastic fibers have been detected, thus demonstrating the influence of keratinocytes on the maturation and organization of the elastic network.

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In a previous work we synthesized a class of new antineoplastic drugs by coupling a cisplatin derivative to a triphenylethylene moiety similar to the antiestrogen, tamoxifen. These drugs differ in the number of hydroxy functions on the triphenylethylene rings and in the length of the linking arm. To gain more insight into the cellular mechanism by which these new drugs act on cells, we studied, using differential scanning calorimetry, the effects of these compounds on the phase transition of membrane phospholipid (distearoyl phosphatidyl choline (DSPC)), and correlated these effects to drug cytotoxicity. The drugs without hydroxy function showed the highest cytotoxicity and induced little change on the thermogram of DSPC. Contrarily, the drugs bearing two or three hydroxy groups were less toxic, but induced important modifications of the thermogram. We suggest that the drugs with no hydroxy group enter the membrane, with the triphenylethylene moiety localized deep within the hydrophobic core of the bilayer and do not affect the cooperativity region (C2-C8). In contrast, drugs which bear hydroxy groups on the triphenylethylene rings system perturb the phospholipid molecular arrangement; this may be due either to the additional steric hindrance of the hydroxy functions in the core of the bilayer, or to their hydrophilic effect on the polar head of the lipid. In vitro, the cytotoxic effect of these drugs seems not to be related to their affinity for the estrogen receptor. We suggest that the addition of a triphenylethylene moiety to the platinum(II) complexes increases the hydrophobicity, and consequently the resulting drugs become more permeable to the membrane, particularly the non-hydroxylated triphenylethylene derivatives.

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Although premature ejaculation (RE) is considered the most common male sexual dysfunction, progress in understanding it has been hampered by the lack of a commonly accepted definition. Several different criteria have been used to assess RE with no attempt to validate the extent to which they are related. The current study assessed, in a sample of university men, the occurrence and relationships among four commonly applied RE criteria: perceived control over the occurrence of ejaculation, latency from vaginal penetration to ejaculation, satisfaction with perceived degree of ejaculatory control, and concern over the occurrence of rapid ejaculation. Other aspects of ejaculatory behavior were also assessed such as the thoughts and techniques men used to prolong intercourse and delay ejaculation. Results indicated that although the four RE criteria were significantly correlated, the magnitudes of these correlations were small. This suggests that these commonly used RE criteria are largely independent and are not interchangeable and that research in this area needs to adopt a multivariate approach to assessment. Men's erotophilia/erotophobia was not related to RE. While use of several ejaculatory delaying techniques were individually and jointly predictive of ejaculatory control and/or ejaculatory evidence, there was no strong support for any specific pattern of behavior that is related to better control and longer latencies. Further, experts were not able to distinguish the ejaculatory delaying techniques of the men with the poorest control and shortest latencies from those of the men with the best control and longest latencies.

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"This paper uses pooled 1971, 1981, and 1986 Canadian census data to evaluate the extent to which (1) the earnings of Canadian immigrants at the time of immigration fall short of the earnings of comparable Canadian-born individuals, and (2) immigrants' earnings grow more rapidly over time than those of the Canadian born. Variations in the labour market assimilation of immigrants according to their gender and country of origin are also analysed. The results suggest that recent immigrant cohorts have had more difficulty being assimilated into the Canadian labour market than earlier ones, an apparent consequence of recent changes in Canadian immigration policy, labour market discrimination against visible minorities, and the prolonged recession of the early 1980s." (SUMMARY IN FRE)

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A man's ability to control the timing of his ejaculation is a key aspect of his and his partner's sexual pleasure. This paper reviews the available clinical and experimental literature on rapid ejaculation (RE) highlighting methodological weaknesses common to research in the area. The numerous operational definitions of RE are reviewed. Inconsistencies among these definitions have led to difficulties in comparing studies. Empirical support for existing theories regarding the etiology of RE are reviewed. None has clear empirical support as being causally related to RE. The success of therapeutic interventions for RE are evaluated. The active ingredient(s) of therapeutic interventions for RE and the mechanisms by which they work have yet to be identified. Further, these treatments are far from universally successful, suggesting a need for additional approaches. A multivariate approach to operationalizing RE based on both ejaculatory latency and perceived control is proposed. This approach would also facilitate the understanding of both etiological and treatment issues.

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"The purpose of this paper is to examine the impact of immigration on the market of some disadvantaged groups of Canadian workers, i.e., women, younger workers, and workers with low levels of schooling. The analysis is done with the micro-data from the 1981 and 1986 Canadian Censuses. Based on their distribution by industry and occupation, recent immigrants are more likely to compete with the disadvantaged groups of Canadian workers than with advantaged ones. However, an analysis of relative earnings by region shows that the relationship between the earnings differentials and the proportion of immigrants is not the same for all the disadvantaged groups. In particular, earnings differentials between men and women tend to be lower in the regions with a high proportion of immigrants than in those with a low proportion." (SUMMARY IN ENG)

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PIP: In the research reported here, the authors examine the relation of 82 medical students' feelings about sex to their level of sexual knowledge, willingness to treat patients with sexual concerns, and participation in an elective sex education course. 82 of the 100 2nd-year students at an Ontario medical school in 1986 participated in the initial phase of this survey research. This sample contains 37 men. 37 of the students (19 of them men) completed the follow-up measures. The results show that the erotophobic students (those with negative feelings about sexuality) had significantly lower levels of sexual knowledge and were significantly less likely to participate in an elective human sexuality course than the erotophilic students (those with positive feelings about sexuality). Moreover, the erotophobic students who took part in the sexuality course benefited from it less than did the erotophilic students as measured by their willingness to treat patients with sexual concerns. Finally, although the students overall were relatively knowledgeable about sex and were relatively willing to treat patients with sexual concerns, trouble in gaps in specific sexual knowledge and in willingness to treat patients with certain sexual concerns (such as acquired immunodeficiency syndrome) were identified. Medical schools need to structure sex education in ways that take account of students' ambivalent feelings about sex and need to provide sex education that increases both sexual knowledge and willingness to treat patients with sexual concerns.^ieng

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In the research reported here, the authors examined the relation of 82 medical students' feelings about sex to their level of sexual knowledge, willingness to treat patients with sexual concerns, and participation in an elective sex education course. The results showed that the erotophobic students (those with negative feelings about sexuality) had significantly lower levels of sexual knowledge and were significantly less likely to participate in an elective human sexuality course than the erotophilic students (those with positive feelings about sexuality). Moreover, the erotophobic students who took part in the sexuality course benefited from it less than did the erotophilic students as measured by their willingness to treat patients with sexual concerns. Finally, although the students overall were relatively knowledgeable about sex and were relatively willing to treat patients with sexual concerns, troubling gaps in specific sexual knowledge and in willingness to treat patients with certain sexual concerns (such as acquired immune deficiency syndrome) were identified. Medical schools need to structure sex education in ways that take account of students' ambivalent feelings about sex and need to provide sex education that increases both sexual knowledge and willingness to treat patients with sexual concerns.

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"Between 1976 and 1981 many pople moved out of Quebec, especially anglophones. To the extent that a person's decision to stay or to move may be related to earnings prospects, earnings comparisons with individuals who lived in Quebec in 1981 may suffer from a selection bias. This paper analyses emigration from Quebec and earnings with a two-equation model, using a sample of men drawn from the from the 1981 [Canadian] census. It is found that a selection bias is indeed present for anglophones and that the returns to learning French may be underestimated when that bias is ignored."

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A novel type of cell secretion termed 'microvesicular secretion' has been described recently in the exocrine pancreas. According to this process, microvesicles are released by acinocytes in the pancreas acinar lumen. These microvesicles, identified as 'pancreasomes', were characterized by the presence of a major glycoprotein component originating in the exocrine acinar cell. In the present work, phospholipids of pancreasomes have been identified. Five classes of phospholipid were found: phosphatidylcholines, phosphatidylethanolamines, lysophosphatidylcholines, sphingomyelins and another minor class of ninhydrin-positive phospholipid (phosphatidylserines or lysophosphatidylethanolamines). The ratios of neutral lipids to phospholipids were particularly high (3:1), as estimated by GLC of their fatty acid content. Analysis of fatty acid composition of pancreasomes lipids revealed a very high proportion of two saturated fatty acids, palmitic (40%) and stearic (24%), whereas two main unsaturated fatty acids, oleic (17%) and linoleic (8%), were found in smaller proportions. Differential scanning calorimeter studies on washed pancreasomes indicated that there was no lipid phase transition in their membrane, despite the absence of cholesterol. Our observations show that pancreasomes have an unusual lipid composition and confirm our previous conclusion based on protein analysis that the release of pancreasomes occurs according to an hitherto undescribed type of secretion, in which a glycoprotein is released associated with specific domains of the luminal plasma membrane.

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