14-3-3ζ regulates adipogenesis by modulating chromatin accessibility during the early stages of adipocyte differentiation.

We previously established the scaffold protein 14-3-3ζ as a critical regulator of adipogenesis and adiposity, but the temporal specificity of its action during adipocyte differentiation remains unclear. To decipher if 14-3-3ζ exerts its regulatory functions on mature adipocytes or on adipose precursor cells (APCs), we generated Adipoq14-3-3ζKO and Pdgfra14-3-3ζKO mouse models. Our findings revealed a pivotal role for 14-3-3ζ in APC differentiation in a sex-dependent manner, whereby male and female Pdgfra14-3-3ζKO mice display impaired or potentiated weight gain, respectively, as well as fat mass. To better understand how 14-3-3ζ regulates the adipogenic transcriptional program in APCs, CRISPR-Cas9 was used to generate TAP-tagged 14-3-3ζ-expressing 3T3-L1 preadipocytes. Using these cells, we examined if the 14-3-3ζ nuclear interactome is enriched with adipogenic regulators during differentiation. Regulators of chromatin remodeling, such as DNMT1 and HDAC1, were enriched in the nuclear interactome of 14-3-3ζ, and their activities were impacted upon 14-3-3ζ depletion. The interactions between 14-3-3ζ and chromatin-modifying enzymes suggested that 14-3-3ζ may control chromatin remodeling during adipogenesis, and this was confirmed by ATAC-seq, which revealed that 14-3-3ζ depletion impacted the accessibility of up to 1,244 chromatin regions corresponding in part to adipogenic genes, promoters, and enhancers during the initial stages of adipogenesis. Moreover, 14-3-3ζ-dependent chromatin accessibility was found to directly correlate with the expression of key adipogenic genes. Altogether, our study establishes 14-3-3ζ as a crucial epigenetic regulator of adipogenesis and highlights the usefulness of deciphering the nuclear 14-3-3ζ interactome to identify novel pro-adipogenic factors and pathways.

Plakoglobin regulates adipocyte differentiation independently of the Wnt/ß-catenin signaling pathway.

The scaffold protein 14-3-3ζ is an established regulator of adipogenesis and postnatal adiposity. We and others have demonstrated the 14-3-3ζ interactome to be diverse and dynamic, and it can be examined to identify novel regulators of physiological processes, including adipogenesis. In the present study, we sought to determine if factors that influence adipogenesis during the development of obesity could be identified in the 14-3-3ζ interactome found in white adipose tissue of lean or obese TAP-tagged-14-3-3ζ overexpressing mice. Using mass spectrometry, differences in the abundance of novel, as well as established, adipogenic factors within the 14-3-3ζ interactome could be detected in adipose tissues. One novel candidate was revealed to be plakoglobin, the homolog of the known adipogenic inhibitor, ß-catenin, and herein, we report that plakoglobin is involved in adipocyte differentiation. Plakoglobin is expressed in murine 3T3-L1 cells and is primarily localized to the nucleus, where its abundance decreases during adipogenesis. Depletion of plakoglobin by siRNA inhibited adipogenesis and reduced PPARγ2 expression, and similarly, plakoglobin depletion in human adipose-derived stem cells also impaired adipogenesis and reduced lipid accumulation post-differentiation. Transcriptional assays indicated that plakoglobin does not participate in Wnt/ß-catenin signaling, as its depletion did not affect Wnt3a-mediated transcriptional activity. Taken together, our results establish plakoglobin as a novel regulator of adipogenesis in vitro and highlights the ability of using the 14-3-3ζ interactome to identify potential pro-obesogenic factors.

RSK promotes G2 DNA damage checkpoint silencing and participates in melanoma chemoresistance.

The incidence of malignant melanoma is growing rapidly worldwide and there is still no effective therapy for metastatic disease. This type of cancer is highly resistant to conventional DNA-damaging chemotherapeutics, and intense research has been dedicated for understanding the molecular pathways underlying chemoresistance. The Ras/mitogen-activated protein kinase (MAPK) signalling pathway is often deregulated in melanoma, which frequently harbours activating mutations in NRAS or BRAF. Herein, we demonstrate that the MAPK-activated protein kinase RSK (p90 ribosomal S6 kinase) contributes to melanoma chemoresistance by altering their response to chemotherapeutic agents. We find that RSK phosphorylates checkpoint kinase 1 (Chk1) at an inhibitory site, Ser280, both in vitro and in vivo. Our results indicate that RSK is the predominant protein kinase operating downstream of mitogens and oncogenes of the Ras/MAPK pathway, and consistent with this, we find that RSK constitutively phosphorylates Chk1 in melanoma. We show that RSK inhibition increases Chk1 activity in response to DNA-damaging agents, suggesting that the Ras/MAPK pathway modulates Chk1 function and the response to DNA damage. Accordingly, we demonstrate that RSK promotes G2 DNA damage checkpoint silencing in a Chk1-dependent manner, and find that RSK inhibitors sensitize melanoma cells to DNA-damaging agents. Together, our results identify a novel link between the Ras/MAPK pathway and the DNA damage response, and suggest that RSK inhibitors may be used to modulate chemosensitivity, which is one of the major obstacles to melanoma treatment.

Cryopreservation of intact human articular cartilage.

Damaged articular cartilage (AC) impairs joint function and many treatment techniques are being investigated to determine their long term results. Successful cryopreservation of AC can provide a reliable source of intact matrix with viable chondrocytes to maintain the cartilage over long periods of time. This study investigated the application of an established cryopreservation protocol to determine the recovery of intact chondrocytes from human AC. Ten millimeter diameter osteochondral dowels were harvested from two human donors. The cryopreservation protocol was performed and the samples were rapidly warmed from varying experimental holding temperatures (-10, -20, -30, -40 degrees C), with and without plunging into liquid nitrogen, using 1 M dimethyl sulfoxide as cryoprotectant. The cartilage was stained with membrane integrity dyes and viewed under fluorescence microscopy. The percent of intact chondrocytes was compared to fresh controls. Low recovery of intact chondrocytes was recorded from all temperature levels with and without cryoprotectant. The results of this experiment demonstrated that the cryopreservation procedure used to achieve moderate success with intact sheep AC was not successful with intact human AC and further investigation is required.

Changing trends in mortality and admissions to hospital for elderly patients with congestive heart failure in Montreal.

BACKGROUND: Congestive heart failure (CHF) is a common disease requiring admission to hospital among elderly people and is associated with a high mortality rate. The objective of this study was to examine trends in CHF mortality and admissions to hospital in Montreal between 1990 and 1997 for individuals aged 65 years or more. METHODS: We obtained information about deaths from the Quebec Death Certificate Registry database and information about admissions to hospital from the Quebec Med-Echo database. Patients with a primary diagnosis that was classified as ICD-9 code 428 were considered cases of CHF. RESULTS: Although age-adjusted rates of mortality from CHF did not change significantly between 1990 and 1997, the annual rate of admission to hospital for CHF increased from 92 per 10,000 population in 1990/91 to 124 per 10,000 population in 1997/98 (p < 0.01). Deaths due to CHF, expressed as a proportion of all cardiovascular deaths, increased among women from 5.6% in 1990 to 6.2% in 1997 (p = 0.01). The rate of readmission for all causes following a first admission for CHF during that year rose over the study period from 16.6% to 22.0% within one month (p < 0.001) and from 46.7% to 49.4% within 6 months (p = 0.03). Conversely, mean annual length of stay per admission decreased from 16.4 days in 1990/91 to 12.2 days in 1997/98. INTERPRETATION: The increase in rates of admission to hospital for CHF and the stable rates of CHF mortality suggest that the management of CHF and its antecedents has improved in recent years.

Standard anatomical medullary locking (AML) versus tricalcium phosphate-coated AML femoral prostheses.

OBJECTIVES: To compare the preliminary rate and amount of bony ingrowth and calcar resorption between patients receiving either a standard anatomical medullary locking (AML) or a tricalcium phosphate (TCP)-coated AML femoral prosthesis and to compare preliminary clinical results. DESIGN: A prospective, randomized, double-blind clinical trial. SETTING: An acute care tertiary institution. PATIENTS: Between January 1993 and March 1995, 92 patients underwent primary total hip arthroplasty (THA). They were randomized to 2 groups of 46--a control group or a treatment group. Of the 46 subjects enrolled in each group, no significant differences were seen preoperatively with respect to age, sex, diagnosis, clinical and radiographic assessment. Seventy-one patients were followed up for 24 months. INTERVENTIONS: Insertion of either a standard AML femoral implant (control group) or a TCP-coated AML femoral implant (treatment group). OUTCOME MEASURES: The degree of hypertrophy, calcar atrophy and the number of spot welds on standard postoperative radiographs at 6, 12 and 24 months. Clinically, assessment according to the Société internationale de chirurgie orthopédique et de traumatologie (SICOT) scale and a 100-point visual analogue scale (VAS) for pain. RESULTS: There were no prosthetic stem revisions in either group at the 24-month follow-up. Radiographically, bony ingrowth was not significantly different in the TCP-coated stem, by chi2 analysis of the degree of hypertrophy and number of spot welds present. Also by chi2 analysis, the degree of calcar atrophy was not significantly different between groups. The mean VAS score for pain at 24 months was 12.5 for the control and 12.1 for the treatment group. No significant differences were seen in any of the clinical categories of the SICOT Scale over the 24-month interval. CONCLUSION: The objective of TCP-coating--to increase the rate and amount of bony ingrowth while reducing the rate of calcar resorption in non-cemented THA--was not achieved by 24 months postoperatively in our study.

Severe complications associated with varicella: Province of Quebec, April 1994 to March 1996.

OBJECTIVE: To determine the frequency and severity of serious complications associated with varicella in Quebec; the frequency and severity of cases of congenital varicella; and hospital costs associated with hospitalizations for varicella. STUDY DESIGN: All hospitalizations related to varicella were identified through the use of a hospital data bank and pertinent data were collected from hospital records. SETTING: Province of Quebec with a population of 6,895,960 people. STUDY POPULATION: All cases with a principal or secondary diagnosis of varicella hospitalized in Quebec between April 1, 1994 and March 31, 1996. OUTCOME MEASURES: Types of complications and reason for hospitalization, risk of complications and calculation of associated costs were studied. RESULTS: Nine hundred nine eligible hospitalizations were identified between April 1, 1994 and March 31, 1996. In all, 583 (64.1%) hospitalizations were for the treatment of complications, 127 (14.0%) for administration of intravenous acyclovir and 199 (21.9%) for supportive care. Healthy people accounted for 644 (70.8%) hospitalizations and immunosuppressed individuals for 136 (15.0%). Among children, one-half of the principal complications were skin infections, while 13.5% and 8.4% of principal complications were pneumonia and neurological complications, respectively. Among adults, the most common complication was pneumonia, with a rate of 43.5%, followed by thrombocytopenia and skin infections, with rates of 22.2% and 14.8%, respectively. The complication rate was 29.2 cases/10,000 cases of varicella. CONCLUSIONS: Although perceived as a benign childhood disease by the general population, varicella may be accompanied by severe complications. Morbidity associated with varicella is one of the elements that must be considered when evaluating the usefulness of varicella vaccine.

The use of prescription claims databases in pharmacoepidemiological research: the accuracy and comprehensiveness of the prescription claims database in Québec.

Despite the potential benefits of using prescription claims databases for pharmacoepidemiological research, little work has been reported on the nature of available information or its accuracy. The purpose of this study was to describe information contained within the prescription claims database in Québec, and to assess the accuracy of drug information that might be used to monitor drug exposure and physician prescribing. The comprehensiveness of the prescriptions claims database was assessed by examining 1,917,214 records of dispensed prescriptions for a regionally stratified random sample of 65,349 Québec elderly in 1990. We found that values in key fields (individual identifiers, drug, quantity, date dispensed and duration) were missing or out of range in 0-0.4% of records. The accuracy of data were examined in 723 prescriptions filled by 306 elderly patients attending one internal medicine clinic. Of these prescriptions, 83% were filled by the patient and correctly identified the patient and drug and in 89% of these 599 records, the prescribing physician was correctly identified. The quantity and duration of the prescriptions were accurate in 69.1% and 72.1% of records, respectively. We conclude that the prescription claims database in Québec may represent one of the most accurate means of determining drugs dispensed to individuals. There may be limitations in using this database for dosing information.

Médicarte software developed for the Quebec microprocessor health card project.

The Quebec Patient Smart Card Project is a Provincial Government initiative under the responsibility of the Rgie de l'assurance-maladie du Québec (Quebec Health Insurance Board). Development, implementation, and assessment duties were assigned to a team from Université Laval, which in turn joined a group from the Direction de la santé publique du Bas-St-Laurent in Rimouski, where the experiment is taking place. The pilot project seeks to evaluate the use and acceptance of a microprocessor card as a way to improve the exchange of clinical information between card users and various health professionals. The card can be best described as a résumé containing information pertinent to an individual's health history. It is not a complete medical file; rather, it is a summary to be used as a starting point for a discussion between health professionals and patients. The target population is composed of persons 60 years and over, pregnant women, infants under 18 months, and the residents of a small town located in the target area, St-Fabien, regardless of age. The health professionals involved are general practitioners, specialists, pharmacists, nurses, and ambulance personnel. Participation in the project is on a voluntary basis. Each health care provider participating in the project has a personal identification number (PIN) and must use both an access card and a user card to access information. This prevents unauthorized access to a patient's card and allows the staff to sign and date information entered onto the patient card. To test the microprocessor card, we developed software based on a problem-oriented approach integrating diagnosis, investigations, treatments, and referrals. This software is not an expert system that constrains the clinician to a particular decisional algorithm. Instead, the software supports the physician in decision making. The software was developed with a graphical interface (Windows 3.1) to maximize its user friendliness. A version of the software was developed for each of the four groups of health care providers involved. In addition we designed an application to interface with existing pharmaceutical software. For practical reasons and to make it possible to differentiate between the different access profiles, the information stored on the card is divided in several blocks: Identification, Emergency, History (personal and family), Screening Tests, Vaccinations, Drug Profile, General follow-up, and some Specific follow-ups (Pregnancy, Ophthalmology, Kidney failure, Cardiology, Pediatrics, Diabetes, Pneumology, Specific parameters). Over 14,000 diagnoses and symptoms are classified with four levels of precision, the codification being based on the ICPC (International Classification for Primary Care). The software contains different applications to assist the clinician in decision making. A "Drug Advisor" helps the prescriber by detecting possible interactions between drugs, giving indications (doses) and contraindications, cautions, potential side-effects and therapeutic alternatives. There is also a prevention module providing recommendations for vaccination and periodic examinations based on the patient's age and sex. The pharmaceutical, vaccination, and screening tests data banks are updated every six months. These sections of the software are accessible to access card holders at any times, even without a patient card, and constitute in themselves an interesting clinical tool. We developed a software server (SCAM) allowing the different applications to access the data in a memory card regardless of the type of memory card used. Using a single high level command language, this server provides a standardized utilization of memory cards from various manufacturers. It ensures the compatibility of the applications using the card as a storage medium. (abstract truncated)

A microprocessor card software server to support the Quebec health microprocessor card project.

The Quebec Health Smart Card Project is advocating the use of a memory card software server[1] (SCAM) to implement a portable medical record (PMR) on a smart card. The PMR is viewed as an object that can be manipulated by SCAM's services. In fact, we can talk about a pseudo-object-oriented approach. This software architecture provides a flexible and evolutive way to manage and optimize the PMR. SCAM is a generic software server; it can manage smart cards as well as optical (laser) cards or other types of memory cards. But, in the specific case of the Quebec Health Card Project, SCAM is used to provide services between physicians' or pharmacists' software and IBM smart card technology. We propose to expose the concepts and techniques used to provide a generic environment to deal with smart cards (and more generally with memory cards), to obtain a dynamic an evolutive PMR, to raise the system global security level and the data integrity, to optimize significantly the management of the PMR, and to provide statistic information about the use of the PMR.

Can a patient smart card improve decision making in a clinical setting?.

In the health field, clinical information is the raw material for the clinician delivering health services. Therefore, the clinical information available to the physician is often incomplete or even non¿existent upon consultation. Furthermore, the reconstruction of the medical history, which is the most important source of data for the clinician to establish a diagnosis and initiate a treatment, suffers from many constraints. The smart card, like the one used in Quebec's project, could ease the physician's decision-making by allowing fast access to accurate and pertinent data. The smart card is a major asset in the present health system.

Centrifugal osteopetrosis: appendicular sclerosis with relative sparing of the vertebrae.

A previously unreported pattern of bone involvement in autosomal dominant osteopetrosis is described in three affected members of a Vietnamese kindred. The hands, feet, distal bones, and skull were markedly osteosclerotic on radiologic examination. The vertebrae displayed very minimal thickening of the endplates in two of the cases, and no visible involvement in the third. The vertebral bone density (assessed by dual-energy X-ray absorptiometry) was markedly elevated, suggesting that the spine was not completely spared. This pattern contrasts with the predominantly axial distribution of the recognized variants of osteopetrosis.

[Effect of patient education on neuroleptic treatment of young psychotic patients]. / Effets d'une éducation au traitement neuroleptique chez de jeunes psychotiques.

This study verifies the effect of the neuroleptic treatment teaching module, the French translation of the Medication Management Module produced by the social skills training programs. Twenty patients from an outpatient clinic (with schizophreniform or schizoaffective schizophrenia) were assigned at random to a test group (n = 10) or a control group (n = 10). The pre-test evaluation found that the two groups were the same with regard to 13 significant parameters. The experimenters used French translations of well-known instruments, and the double-blind method was applied to their respective observations throughout the study. Results were obtained by applying the neuroleptic treatment teaching module three hours per week for two to three months. The post-test evaluation revealed that patients who had been exposed to the education module had an improved understanding of schizophrenia and the medication required to treat it than patients who had not been exposed. The dose of medication prescribed between pre- and post-test evaluations were able to more effectively stabilize patients who had received education than patients who had not. Nevertheless, the education module continues to have no significant effect on the symptomatology (according to the Brief Psychiatric Rating Scale) and final SAS-II social scores of schizophrenics.

Revision arthroplasty of the proximal femur using allograft bone.

Revision arthroplasty of the hip may require restoration of bone stock on the femoral side to provide bone support for the new implant and restore anatomy and leg length. Large cortical defects can be reconstructed best with allograft bone because of the quality and quantity of the bone required. In this article, the surgical technique and results of cortical allograft as full circumferential and cortical strut grafts are presented.

[Psychiatric emergencies in the context of community mental health services]. / Les urgences psychiatriques dans un contexte de sectorisation.

Psychiatric services dispensed according to geographic sectors has been a reality of the Montréal area psychiatric care system for about fifteen years. In a dense urban environment where the territorial limits of sectors do not necessarily follow the borders of residential areas, divisions by sector can create serious access problems. On a different note, when the distribution of mental health services is patterned after the main urban arteries, sectorialization becomes the validation of an existing situation, its success thereby ensured by the force of circumstances. In this article, the access to emergency psychiatric services over the sectorialized territory of Ile Jesus is examined based on archival data provided by Sacré-Coeur and Cité de la Santé hospitals. The data reveal that patients with a psychiatric ailment present themselves to the emergency ward of the hospital of their sector. These patients of emergency services are characterized by usage patterns that are no different from those of users of all types of health care services, psychiatric or not, regardless of the reason of the visit. However, the place of use of sectorialized psychiatric services has a halo effect on non-sectorialized psychiatric services. The impact of sectorialization on the usage and access of services is therefore a complex phenomenon.

A reproducible porcine vertebral fracture for biomechanical testing of spinal fixation devices.

To evaluate vertebral fracture fixation devices in the laboratory, it is necessary to produce identical and unstable fractures either in anatomic specimen or animal models. Consistent achievement of this goal has not been reported in the literature. This report presents a technique for the study of reproducibility for a particular vertebral fracture model. A precise anterior defect was created in a vertebra of each specimen drawn from a homogeneous population of mature sow spines. The spines were loaded to failure. Fracture reproducibility was shown by measurement of load and displacement, and confirmed by roentgenographic evaluation. The technique is easily applied to human specimens. Because there is a plethora of fracture fixation devices based on hooks, wires, or, more recently, plates and pedicle screws, the reliability of comparative testing of these devices in the laboratory requires an appropriate and reproducible fracture.

Proximal femoral allografts in revision hip arthroplasty.

We followed prospectively 69 patients with 78 proximal femoral allografts performed for revision of total hip arthroplasty for an average of 36 months (range 29 to 68). Large fragment proximal femoral allografts and cortical strut allografts were successful in 85%. Grafts smaller than 3 cm in length (calcar grafts) were clinically successful in 81%, but 50% underwent significant radiographic resorption. We conclude that large proximal femoral allografts and cortical strut allografts provide dependable reconstruction of bone stock deficiencies during revision total hip arthroplasty.

Zopiclone versus flurazepam in insomnia: prolonged administration and withdrawal.

Zopiclone (7.5 mg), a cyclopyrrolone derivative with a 6.5 h half-life, and flurazepam (30 mg) were compared to placebo in a randomized double-blind study involving 36 adult patients suffering from insomnia. All previous psychotropic drugs were discontinued 1 week prior to the study. During 4 weeks, 12 patients received zopiclone, 12 flurazepam and the others placebo. Thereafter, all patients received single-blind placebo for 3 nights. Rapidity of sleep onset, sleep duration, frequency of nocturnal awakenings, psychomotor coordination and side-effects were assessed daily with a questionnaire and a symptom checklist. The results of the study suggest that zopiclone 7.5 mg was at least as potent as flurazepam 30 mg in inducing and maintaining sleep. Both drugs maintained their efficacy during the 4 weeks of treatment. However, the two drugs differed in that flurazepam impaired psychomotor coordination whereas zopiclone did not demonstrate daytime protracted effects on psychomotor performance. Upon discontinuation of drug treatment, score values of the different sleep parameters under study returned to the baseline values. Side-effects were mild and consistent with earlier studies.