[Regenerative medicine: stem cells, cellular and matricial interactions in the reconstruction of skin and cornea by tissue engineering]. / La médecine régénératrice : les cellules souches, les interactions cellulaires et matricielles dans la reconstruction cutanée et cornéenne par génie tissulaire.

Considering that there is a shortage of organ donor, the aim of tissue engineering is to develop substitutes for the replacement of wounded or diseased tissues. Autologous tissue is evidently a preferable transplant material for long-term graft persistence because of the unavoidable rejection reaction occuring against allogeneic transplant. For the production of such substitutes, it is essential to control the culture conditions for post-natal human stem cells. Furthermore, histological organization and functionality of reconstructed tissues must approach those of native organs. For self-renewing tissues such as skin and cornea, tissue engineering strategies must include the preservation of stem cells during the in vitro process as well as after grafting to ensure the long-term regeneration of the transplants. We described a tissue engineering method named the self-assembly approach allowing the production of autologous living organs from human cells without any exogenous biomaterial. This approach is based on the capacity of mesenchymal cells to create in vitro their own extracellular matrix and then reform a tissue. Thereafter, various techniques allow the reorganization of such tissues in more complex organ such as valve leaflets, blood vessels, skin or cornea. These tissues offer the hope of new alternatives for organ transplantation in the future. In this review, the importance of preserving stem cells during in vitro expansion and controlling cell differentiation as well as tissue organization to ensure quality and functionality of tissue-engineered organs will be discussed, while focusing on skin and cornea.

Extra-skeletal impact of vitamin D supplementation protocol in an adult population with cystic fibrosis.

BACKGROUND: Due to lack of vitamin D absorption in patients with cystic fibrosis (CF), vitamin D supplementation becomes necessary. Our aim was to study the association between serum vitamin D levels and key clinical factors, such as nutritional status, pulmonary function and pulmonary exacerbations (PEx) frequency, in an adult CF population. METHODS: Prospective analysis of a published vitamin D (VitD3) supplementation protocol (N = 200 adult patients) over a follow-up period of 5 years. Data were collected from the medical files before (baseline) and after (follow-up) the implementation of the VitD3 supplementation protocol, between 2009 and 2014. Serum samples to measure vitamin D were also collected at baseline and follow-up. RESULTS: A positive relationship between serum vitamin D and lung function was observed at baseline (R = 0.158, P = 0.027), but it disappeared at follow-up (P = 0.454). There was no association between serum vitamin D levels and body mass index. At follow-up, patients with significantly higher serum vitamin D levels were women, older in age, had CF-related diabetes or had a history of recurring PEx. CONCLUSION: No direct link was observed between heightened serum vitamin D and lung function or BMI in an adult CF population. We suggest that better compliance to treatments and closer follow-up from health professionals could partially explain why such patients reached higher vitamin D serum levels.

[Pilot study about pharmaceutical care implantation in a general paediatric unit in a French hospital. France-Québec collaboration and comparison]. / Etude pilote sur la mise en place des soins pharmaceutiques dans le service de pédiatrie générale d'un hôpital français. Collaboration et comparaison franco-québécoise.

UNLABELLED: STATE OF THE PROBLEM AND OBJECTIVES: French pharmacists are quasi absent from hospital wards. Our objective was to describe the implantation of pharmaceutical care in a patient unit of a French paediatric hospital. MATERIAL AND METHODS: Following an internship in pharmaceutical care at the Sainte-Justine hospital (SJ) in Montreal, a French pharmacist returned to France to implement the pharmaceutical model in a paediatric unit at Robert Debré hospital (RD) in Paris. We first collected pharmaceutical interventions carried out during a 5-month period. In a second phase, we compared pharmaceutical interventions provided by the team composed of the same French pharmacist and a pharmacist from Québec in both settings during 14 days respectively. RESULTS: In the first phase, 556 interventions were done (8.2+/-2,0 per day) with a significant increase observed during the first 2 months. In the second phase, 216 interventions were done at RD and 174 at SJ. The interventions were mainly related to drug information, modification of treatment and seamless care with the pharmacy of the hospital or a community pharmacy. The interventions targeted junior (30.5 to 55.4%), senior physicians (16.2 to 38.5%) and pharmacy (11.5 to 16.2%) in the different phases and sites. A high level of physician acceptance was observed, with respectively 86.0 and 93.1% at RD and SJ. DISCUSSION: French pharmacists can apply the pharmaceutical care model following a specific training. Further studies are required to evaluate the feasibility and the impact of pharmaceutical care in France.

Association between glucose intolerance and bacterial colonisation in an adult population with cystic fibrosis, emergence of Stenotrophomonas maltophilia.

BACKGROUND: Diabetes is common in cystic fibrosis (CF). Glucose can be detected in the airway when the blood glucose is elevated, which favours bacterial growth. We investigated the relationship between dysglycemia and lung pathogens in CF. METHODS: Cross-sectional and prospective analysis of CF patients (N=260) who underwent a 2h-oral glucose tolerance test. Clinical data was collected. RESULTS: Stenotrophomonas maltophilia (S. maltophilia) was the sole bacteria increased in dysglycemic (AGT: 20.2%, CFRD: 21.6%) patients compared to normotolerants (NGT: 8.7%). S. maltophilia positive patients with dysglycemia had more pulmonary exacerbation events compared to NGTs (1.22 vs 0.63, P=0.003). The interaction between S. maltophilia colonisation and glucose tolerance status significantly increases the risk of lower lung function (P=0.003). Its growth was not affected by the evolution of the glucose tolerance after three years follow-up. CONCLUSION: Prevalence of S. maltophilia was higher in dysglycemic patients, supporting the idea that S. maltophilia is a marker of disease severity in CF.

Ralstonia mannitolilytica in cystic fibrosis: A new predictor of worse outcomes.

BACKGROUND: Patients with Cystic Fibrosis are subject to repeated respiratory tract infections, with recent increasing isolation of unusual pathogens. Ralstonia species have lately been isolated at our institution, an organism historically frequently misidentified as Burkholderia or Pseudomonas. The prevalence of Ralstonia spp. in cystic fibrosis populations has yet to be determined, along with its clinical implications. CASE PRESENTATIONS: Seven patients out of the 301 followed at our cystic fibrosis clinic have had Ralstonia strains identified in their respiratory tract. Most strains identified were multi-drug resistant. After aquisition of Ralstonia spp., the patients' clinical course was characterized by more frequent and more severe respiratory infections along with prolonged hospitalizations, greater decline of lung function, and greater mortality. The mortality rate in this group of patients was 86%. No other factor that could explain such a dramatic evolution was identified upon review of patient data. Some of the strains involved were recognized as clones on Pulse Field Electrophoresis Gel, raising the question of person-to-person transmission. CONCLUSION: New pathogens are identified with the evolution of the microbiota in cystic fibrosis respiratory tracts. In our cohort of patients, acquisition of Ralstonia spp. was associated with dramatic outcomes in terms of disease acceleration and raised mortality rates. It is of critical importance to continue to better define the prevalence and clinical impact of Ralstonia in cystic fibrosis populations.

Myocardial Perfusion Scans and Mortality in Asymptomatic Patients Awaiting Renal Transplantation.

Cardiac risk assessment for asymptomatic patients awaiting renal transplantation is controversial. Patients awaiting renal transplantation in Southern Saskatchewan from 2005 to 2015 were retrospectively reviewed. Patients underwent cardiac risk stratification with stress myocardial perfusion scan. Baseline clinical characteristics, nuclear scan results, all-cause mortality, and cardiovascular events were analyzed. Abnormal scans were defined as studies with reversible defects, wall motion abnormalities, lung uptake, or transient ischemic dilation. Descriptive statistics and survival analysis were calculated. Charts from 285 consecutive patients with 608 nuclear scans were analyzed. Mean age was 55.2 ± 11.7 years and 34.7% were female. Forty-three (15.1%) patients were transplanted and 99 (40.9%) patients died while awaiting renal transplantation. One hundred fifty-three patients (63.2%) had at least one abnormal scan. The mean follow-up period was 5.47 ± 3.11 years. An abnormal scan was not associated with decreased survival and/or coronary events (hazard ratio: 0.94, P = .77; 95% confidence intervals: 0.62 to 1.43). Patients awaiting renal transplantation in Saskatchewan with abnormal myocardial perfusion scans were not at greater risk of death or coronary events.

[The use of head CT scan in adult trauma victims: an algorithm]. / Le scanner cérébral chez les adultes victimes de traumatismes crâniens mineurs: un arbre décisionnel.

INTRODUCTION: The purpose of this study was to identify, through recursive partitioning, clinically relevant criteria which predict the need for acute neurosurgical intervention in a group of patients with mild head injury. MATERIALS AND METHODS: A retrospective cohort of all adult patients, from April 2000 to March 2001, who sustained a blunt trauma and underwent head CT scan, was reviewed. The following inclusion criteria for mild head injury were used: initial Glasgow Coma Scale (GCS) ranging from 13 to 15; no loss of consciousness lasting more than one hour; no obvious skull fracture; a cranial CT scan performed. We collected demographic and trauma related data, interventions and outcome. Univariate and multivariate analyses were undertaken. In parallel, recursive partitioning was carried out using all variables to elaborate a decision algorithm. RESULTS: There were 405 patients in the sample. CT identified lesions in 12% of patients. Twelve patients (3%) required acute neurosurgical intervention. The recursive partitioning analysis identified three significant sequential nodes: deterioration of the GCS; an initial GCS of 13 vs 14 or 15; and the presence of associated injuries or comorbid conditions. CONCLUSIONS: A simple three step rule predicts the need for acute neurosurgical intervention based on clinical findings: a deteriorating GCS; an initial GCS of 13; and the presence of associated injuries or comorbid conditions.

Diabetes: a major co-morbidity of cystic fibrosis.

Cystic fibrosis-related diabetes (CFRD) is a frequent complication of cystic fibrosis, its prevalence increases with age of patient and is close to 30% at the age of 30 years. As life expectancy greatly increases, the number of cystic fibrosis patients developing diabetes will increase too. CFRD shares some features with type 1 and type 2 diabetes, initial phase is characterised by postprandial hyperglycaemia followed by a progression toward insulin deficiency. Insulin deficiency is an essential factor in the development of diabetes with an additional contribution of insulin resistance. Systematic screening with an oral glucose tolerance test is recommended from the age of 14 years because clinical signs of CFRD are often confused with signs of pulmonary infection and CFRD occurrence is associated with weight and pulmonary function deterioration. In observational studies CFRD diagnosis is associated with a significant increase in mortality, while treatment allow correction of weight and lung deterioration suggesting that CFRD has a significant impact on CF evolution. Microvascular complications are recognised, although paucity of data does not permit a clear description of their natural history. Annual screening for microvascular complication is recommended. There is no evidence by now that CF patients develop macrovascular complications. The only recommended pharmacological treatment is insulin therapy.

Direct evidence for diazepam modulation of GABAA receptor microscopic affinity.

Alteration of agonist affinity is a potential mechanism for pharmacological modulation of ligand-gated receptor channel function. The time course for receptor activation and current onset is determined by the combined rates for two kinetic transitions that underlie the protein confirmations for binding agonist and channel gating. Using ultrafast ligand exchange techniques, we distinguish between these previously difficult to separate events and demonstrate their independent pharmacological modulation. Diazepam, which increases apparent affinity of gamma-aminobutyric acid (GABA) to GABAA receptors, was used to examine its effects on GABA binding and ion channel gating of expressed alpha 2 beta 1 gamma 2 receptors from excised outside-out patches of acutely transfected HEK 293 cells. Diazepam increased rates of current onset evoked by low concentrations (< 1 mM) but not at saturating GABA concentrations. Furthermore, rates of current decay were not affected during brief applications of GABA, and thus, demonstrated a diazepam specific effect on ligand binding affinity and not channel gating kinetics. However, current decay during and following prolonged GABA applications were altered by diazepam in a fashion similar to that for higher concentrations of GABA which also increased receptor desensitization. These findings and analysis by computer modeling indicated that diazepam likely enhances GABA receptor currents primarily by accelerating GABA association to its receptor at the first agonist binding site. These results provide the first direct physiological evidence for pharmacological modulation of microscopic binding affinity of GABA receptors.

Redistribution of spatial representation in the hippocampus of aged rats performing a spatial memory task.

Young and old rats performed on a maze according to a forced-choice and then a spatial memory procedure either in the same or a different environment. Aged rats were slower to learn the spatial memory task when tested in the same, but not in a different, room. One interpretation of this pattern of results is that although old rats learn new rules as quickly as young rats, they show less flexibility with old rules and familiar spatial information. Impaired choice accuracy during asymptote performance suggests poor processing of trial-unique information by old rats. Spatial correlates of hippocampal CA1 and hilar cells varied with task demand: CA1 cells of aged rats showed more spatially selective place fields, whereas hilar cells showed more diffuse location coding during spatial memory, and not forced-choice, tests. Such representational reorganization may reflect a compensatory response to age-related neurobiological changes in hippocampus.

Enantioselective routes to both enantiomers of aryl alcohols with a single catalyst antipode: Ru and Os transfer hydrogenation catalysts.

[reaction--see text] The kinetic resolution of secondary aryl alcohols has been investigated. When (CyRuCl(2))(2), (1R,2S)-(+)-cis-1-amino-2-indanol, and KOH or (t)BuOK (catalyst 1) were combined in the presence of (+/-)-alcohols, ee's > 90% were generally observed. When applied to the kinetic resolution of (+/-)-indanol and (+/-)-tetralol, ee's = 99% (R) were observed. In addition, the asymmetric transfer hydrogenation of ketones was investigated with a catalyst, 2, generated in situ from (CyOsCl(2))(2), (1R,2S)-(+)-cis-1-amino-2-indanol, and (t)BuOK, yielding ee's of up to 98% (S).

Onset of action of loratadine and placebo and other efficacy variables in patients with seasonal allergic rhinitis.

In a double-blind study, 185 patients with seasonal allergic rhinitis were randomly assigned to receive 10 mg of loratadine or placebo once daily for three days. On day 1 of treatment, the onset of relief of symptoms within 30 minutes of drug administration was reported by 13% of the loratadine-treated patients and by 4% of the placebo patients (P less than 0.05). At two hours after drug administration, 65% of the loratadine-treated patients and 48% of the placebo patients reported symptom relief. On day 3, the loratadine-treated patients reported a significantly greater relief of symptoms, and according to both physician and patient evaluations, the treatment response was significantly superior in the loratadine-treated than in the placebo patients. The incidence of sedation was 2% in the loratadine group and 1% in the placebo group.

Spatial, movement- and reward-sensitive discharge by medial ventral striatum neurons of rats.

Previous behavioral and acute electrophysiological data have lead researchers to speculate that the nucleus accumbens integrates limbic, reward and motor information. The present study examined the behavioral correlates to single unit activity of the nucleus accumbens and surrounding ventral striatum as a means of evaluating the integrative functioning of this region in an awake animal. Medial ventral striatum (mVS) activity was recorded as rats completed multiple trials on an eight arm radial maze. Neuronal activity was found to correlate with spatial, reward- and movement-related behavioral conditions. While the majority of cells demonstrated correlates of a single type (i.e. either spatial or reward correlates), 6 cells encoded multiple correlates of different types (i.e. spatial and reward correlates). The data suggests that this integrative process can be active both at the level of the individual neuron, and at the structural level. These results are consistent with the hypothesis that the mVS integrates spatial and reward-related information, which in turn influences voluntary motor output structures in order to achieve accurate navigational behavior.

Medial septal modulation of entorhinal single unit activity in anesthetized and freely moving rats.

Reversible inactivation of the medial septal area results in a spatial memory impairment and selective disruption of hilar/CA3, but not CA1, location-specific discharge. The present study examined the possibility that such septal deafferentation produces effects on hippocampal function by altering physiological properties of the primary input and output structures for hippocampus, the entorhinal cortex and the subiculum, respectively. Single unit activity of hippocampal, entorhinal, and subicular cells was recorded before, during, and after septal injection of lidocaine in anesthetized rats. When compared to hippocampal cells, relatively few subicular and entorhinal cells showed a change in mean firing rate following septal inactivation. Entorhinal unit responses to septal inactivation (via tetracaine injection) were also examined in freely moving rats performing a spatial maze task. About one-third of entorhinal cells showed enhanced or reduced firing rates of 40% or more. Also, the spatial distribution of cells found in the superficial, but not deep, entorhinal layers became less clear following septal inactivation. Together, these data are consistent with the hypothesis that manipulation of the medial septum affects hippocampal function via its septosubicular and septo-entorhinal projections in addition to the more direct septohippocampal pathway. Since entorhinal cortical function was affected by tetracaine injection into the septum, it does not appear that direct entorhinal-CA1 afferents were primarily responsible for the maintenance of CA1 location-specific neural activity in previous septal inactivation experiments. Rather, these data are consistent with the hypothesis that the persistence of CA1 place fields was accomplished by intrahippocampal neural network operations.

Cardiopulmonary resuscitation: errors made by pre-hospital emergency medical personnel.

The purpose of the current study was to evaluate the CPR techniques of emergency healthcare professionals (emergency medical technicians, firemen, emergency first responders, CPR instructors). Skills were evaluated using a Laerdal Skillmeter Manikin, which provided a computerized printout of the quantifiable data during the CPR sequence. All of the 66 subjects in the study had completed a recertification course within the last 2 years (mean = 0.86 +/- 0.18, 95% CI). The sequence was videotaped for later viewing and for correlating the errors with the data. In addition, the participants were required to fill in a questionnaire. The most frequently occurring errors were observed in landmarking, overcompression, palpating a carotid pulse and insufficient ventilation. Although 98.5% of participants made an attempt to landmark their position for compression on the sternum, 35.9% of the total compressions performed by all subjects were incorrectly positioned on the patient's chest. Overcompression of the patient's chest accounted for 55.3% of incorrect compressions. Although 94% of participants attempted to verify a carotid pulse, only 45% were able to feel it and therefore stop performing cardiac massage. Of the total ventilations, 49% were below the American Heart Association (AHA) recommended minimum (800 ml). The results of this study showed a high rate of errors occurring in the CPR provided by emergency healthcare professionals.

Brain maturity in regard to the auditory brainstem response in small-for-date neonates.

The auditory brainstem response has been used in neonates at risk of hearing impairment or as a functional measurement of brain maturity. The goal of the present study was to evaluate the auditory brainstem response in small-for-date newborns, in relation to changes observed with fetal maturity in a control group. Compared to controls with similar maturity, a significant delay for the appearance of waves III and V, and between waves I-V was observed in the small-for-date newborns, suggesting an alteration of the auditory pathway within the brainstem rather than an impairment of the peripheral auditive apparatus. Indeed, small-for-date newborns reacted to the test in a similar manner as premature babies in whom such a delay was also observed. Our data would suggest a functional brain immaturity in small-for-date newborns, during the first days of life, in regard to the auditive evoked potential, which may be related to some alterations in brain development reported with fetal malnutrition.

Preventable death classification: interrater reliability and comparison with ISS-based survival probability estimates.

The purpose of the study was to compare the injury-related threat to survival estimated by the Injury Severity Score (ISS) and a committee of experts. The charts of 116 (73 fatalities and 43 survivors) patients with severe injuries were reviewed. A committee of nine clinicians classified each case as survivable, potentially survivable, and nonsurvivable based on anatomical descriptors, mechanism of injury, and patient's age. Majority was used to determine the final committee classification. Based on the ISS values, cases were classified as survivable (9-24), potentially survivable (25-49), and nonsurvivable (> 49). The results showed poor interrater reliability among the nine clinicians with an overall intraclass correlation coefficient of 0.43. The ISS-based classification had high agreement with the final committee classification (overall weighted kappa = 0.71). Lower agreement was observed for falls and with increasing number of injuries. This study has demonstrated no additional benefit for using a committee to classify injury severity on the basis of anatomical damage over applying ISS-based survival probabilities. The continued use of the ISS is supported.

Predictive validity and internal consistency of the pre-hospital index measured on-site by physicians.

Physiological measures of injury are used as triage tools to identify patients that require treatment in trauma centres. The Pre-Hospital Index (PHI) is based on systolic blood pressure, pulse, respiratory rate, (level of) consciousness, and presence of penetrating injury. The present study evaluated the validity and internal consistency of the PHI. The study was based on 628 patients assessed by physicians at the scene. Mean age was 38.7 years (SD = 24.8), and 65% were male. Motor vehicle collisions caused the injury for 45%. The majority had head/neck (56%) and extremity (45%) injuries. Mean PHI was 4.62 (SD = 5.77), 40% had a PHI of zero, 6% between 1 and 3, 32% between 4 and 7, and 21% greater than 7. The associations between PHI and rates of hospital admission, surgery, ICU treatment, mortality, duration of hospitalization, and length of ICU stay were significant (p < 0.001). A total of 260 (41.4%) patients had major trauma requiring treatment at a trauma centre. A PHI > 3 had 83% sensitivity and 67% specificity for identifying these patients. Internal consistency of the PHI variables was above the acceptable limits. This study has shown that the PHI is a valid and reliable physiological measure of injury severity and field triage tool.

Long-term follow-up after adjuvant chemotherapy in completely resected early stage ovarian carcinoma.

OBJECTIVE: To evaluate the impact of standardized staging, surgery and adjuvant chemotherapy on survival of patients with completely resected early ovarian carcinoma. STUDY DESIGN: We performed a multicentric retrospective analysis of 283 patients with early stage ovarian carcinoma consecutively treated between 1977 and 1993. Borderline tumours were excluded. A comprehensive staging was performed during initial laparotomy. Patients were treated by standardized surgical resection and all excepted stage IA received a 6-course adjuvant chemotherapy. RESULTS: Eighty patients were excluded because of incorrect substaging, inadequate surgery and adjuvant therapy. The analysis was performed on 203 patients with completely resected early stage ovarian cancer (139, stage I; 64, stage II). Relapse-free survival and overall survival rates for stage I were 66 and 69%, respectively. Relapse-free survival and overall survival rates for stage II were 57 and 61% respectively. Median time of relapse was 18 months (range, 1-107 months). Sites of relapse were peritoneum (45%), retroperitoneal lymph nodes (37%) and distant metastases (18%). Relapses occurring within 18 months had a median survival after relapse of 9 months while later relapses had a median survival of 22 months (P = 0.005). There was no significant difference in relapse-free and overall survival according to the age, performance status and pathology. Cisplatin-based chemotherapy improved the 10-year overall survival of patients with stage IIB and IIC as compared to chemotherapy without cisplatin (oral melphalan. CMF regimen); 91 vs. 33% (P = 0.012) and 75 vs. 42% (P = 0.05), respectively. Cisplatin-based regimens did not improve survival in stage IA, IB and IIA. CONCLUSIONS: Early ovarian cancers have a good prognosis after comprehensive staging, complete surgery and adjuvant chemotherapy. Cisplatin-based regimens compared to melphalan and CMF showed a significant increase of survival in stage IIB and IIC. Prognosis of relapse depends on the relapse-free interval duration.

Determinants of on-scene time in injured patients treated by physicians at the site.

INTRODUCTION: The controversy surrounding the use of advanced life support (ALS) for the pre-hospital management of trauma pivots on the fact that these procedures could cause significant and life-threatening delays to definitive in-hospital care. In Montreal, Québec, on-site ALS to injured patients is provided by physicians only. The purpose of this study was to identify parameters associated with the duration of scene time for patients with moderate to severe injuries treated by physicians at the scene. HYPOTHESIS: The use of on-site ALS by physicians is associated with a significant increase in scene time. METHODS: A total of 576 patients with moderate to severe injuries are included in the analysis. This group was part of a larger cohort used in the prospective evaluation of trauma care in Montreal. Descriptive statistics, analysis of variance, multiple linear regression, and multiple logistic regression techniques were used to analyze the data. RESULTS: Use of ALS in general was associated with a statistically significant increase in the mean scene time of 6.5 min. (p = .0001). Significant increases in mean scene time were observed for initiation of an intravenous route (mean = 6.6 min., p = .0001), medication administration (mean = 5.7 min., p = .0001), and pneumatic antishock garment (PASG) application (mean = 9.3 min., p = .03). Similar differences were observed for total prehospital time. A significant increase in the relative odds for having long scene times (> 20 min.) also was associated with the use of ALS. This level of scene time was associated with a significant increase in the odds of dying (OR = 2.6, p = .009). CONCLUSION: This study shows that physician-provided, on-site ALS causes significant increase in scene time and total prehospital time. These delays are associated with an increase in the risk for death in patients with severe injuries.