Tissue Engineering for Periodontal Ligament Regeneration: Biomechanical Specifications.

The periodontal biomechanical environment is very difficult to investigate. By the complex geometry and composition of the periodontal ligament (PDL), its mechanical behavior is very dependent on the type of loading (compressive versus tensile loading; static versus cyclic loading; uniaxial versus multiaxial) and the location around the root (cervical, middle, or apical). These different aspects of the PDL make it difficult to develop a functional biomaterial to treat periodontal attachment due to periodontal diseases. This review aims to describe the structural and biomechanical properties of the PDL. Particular importance is placed in the close interrelationship that exists between structure and biomechanics: the PDL structural organization is specific to its biomechanical environment, and its biomechanical properties are specific to its structural arrangement. This balance between structure and biomechanics can be explained by a mechanosensitive periodontal cellular activity. These specifications have to be considered in the further tissue engineering strategies for the development of an efficient biomaterial for periodontal tissues regeneration.

Successful term delivery following second-trimester excision of a massive hydrosalpinx presenting as an adnexal mass in pregnancy: management and considerations.

To the best of the authors' knowledge, a massive hydrosalpinx presenting as an adnexal mass complicating pregnancy has never been reported. They report the case of a 26-year-old female diagnosed with a persistent right adnexal cyst in a pregnancy resulting from spontaneous conception, confirmed to be a 30-cm. hydrosalpinx at the time of surgery. Though laparoscopy was envisioned, due to the size of the mass, a right salpingectomy was performed during the second trimester by laparotomy, and the patient had an uncomplicated course of her pregnancy following the intervention, delivering a healthy infant at term. Herein, the authors explore the potential etiologies and different considerations when faced with an adnexal mass in pregnancy. They emphasize that, though rare and uncommon, a hydrosalpinx should be included in the differential diagnosis of persistent adnexal cysts in pregnancy.

[Pulmonary function test: The testing of children]. / Exploration fonctionnelle respiratoire : explorer l'enfant.

In paediatrics, the pulmonary function test (PFT) is most often performed to support the diagnosis or in follow-up of asthma patients. Whatever the pathology responsible for respiratory symptoms and/or functional impairment, repeated PFTs make it possible to establish a prognosis (pulmonary function trajectories…) and to orient preventive interventions. PFT can be performed routinely from the age of three years, provided that the following requirements are met: suitable techniques and equipment, staff trained to apply the techniques and to receive young children, reference values for each technique indicating the limits of normal values and of between-test significant variation. From the age of three, children can be subjected to tidal breathing measurement of: resistance of the respiratory system (oscillometry, Rrs; airflow interruption, Rint) or of airways specific resistance (sRaw) and functional residual capacity (by applying a dilution technique). With maturity, the child will become capable of mobilizing his or her slow vital capacity to measure total lung capacity (TLC), once again by applying a dilution technique, then later by breathing against a closed shutter (plethysmography TLC and Raw). Finally, the child will be able to carry out forced expiration (forced spirometry) along with all of the other PFTs. It is important to take into account the paediatric adaptations specified in the international recommendations regarding the performance, reproducibility and quality of PFTs targeting this population.

Poverty, Health Care Access Barriers, and Functional Limitations among Individuals with Chronic Obstructive Pulmonary Disease: An 11-Year Cross-sectional Analysis, 2008-2018.

OBJECTIVES: To assess the relationship between poverty, delayed care, unaffordable care, and functional limitations among individuals with chronic obstructive pulmonary disease (COPD). METHODS: Using the National Health Interview Survey data, we selected respondents with COPD, aged 40 years and older. The predictor variables were poverty and measures of delayed and unaffordable care. The outcome variable was functional limitations. We performed a survey-weighted multivariate logistic regression analysis, adjusting for sociodemographic characteristics. RESULTS: Respondents classified as poor had three times the odds of functional limitations compared with those classified as not poor. Respondents who reported having measures of delayed care or unaffordable care had two to nine times and two to four times the adjusted odds of functional limitations compared with those who did not report such measures of delayed and unaffordable care, respectively. CONCLUSIONS: Poverty and delayed and unaffordable care are associated with functional limitations among individuals with COPD.

[Active mind-body movement therapies and pulmonary rehabilitation for people with COPD]. / Thérapies actives du mouvement corps-esprit et réadaptation respiratoire dans la BPCO.

INTRODUCTION: Active body-mind movement therapies are performed with the aim of engaging the person in taking care of their health. They are represented by Qi gong, Tai Chi and yoga. They all include postures, breathing exercises and meditation. When utilized together with traditional medicine, they allow a more holistic view of the patient, thereby facilitating improved quality of life. STATE OF THE ART: While these therapies have been studied in cases of chronic obstructive pulmonary disease, and compared to routine care or walking-type physical activity, they have seldom been studied in the context of respiratory rehabilitation, even though their effects on quality of life and functional capacity are clinically significant, while some comorbidities may likewise be positively impacted. PERSPECTIVES: The application of these therapies should be extended to GOLD grade 1 and 4 patients while studying their effects on the occurrence of bronchial exacerbations. The value of their performance as a replacement for - or complement to - respiratory rehabilitation remains to be evaluated and confirmed. CONCLUSION: These therapies can be used to facilitate behavior change from a preventive and therapeutic standpoint, thereby attenuating the impact of aggravating factors in respiratory disease.

Laryngeal Reinnervation: The History and Where We Stand Now.

Injury to the recurrent laryngeal nerve (RLN) can result in impairment of all three laryngeal functions. The RLN is capable of regeneration, but laryngeal functions in cases of severe injury remain impaired. This permanent impairment is caused by either incomplete regeneration and/or occurrence of laryngeal synkinesis. Laryngeal reinnervation can be approached either nonselectively, focusing on nerve reconstruction, or selectively, focusing on separate target muscle reinnervation. Nonselective reinnervation comprises anastomosis to the mainstem of the RLN leading to reinnervation of both abductor and adductor muscle groups (nerve-based reconstruction). In selective reinnervation, abductor and/or adductor muscles are separately reinnervated (function-based reconstruction). A review of laryngeal reinnervation techniques, results in animal models, and the results achieved in patients are given. The clinical implications of reinnervation in unilateral as opposed to bilateral vocal fold paralysis are considered. For unilateral vocal fold paralysis and nonselective reinnervation, good voice results can be achieved. It has the advantage that no foreign materials need to be implanted and may also be used in a growing larynx in the case of children or adolescents. For bilateral vocal fold paralysis, good functional results, recovery of airway as well as voice, can be achieved with selective (or function-based) reinnervation.

[Respiratory function testing in infants: recommendations on normal values]. / EFR du nourrisson: le point sur les valeurs normales.

The present document is being produced on behalf of the French Society of the Physiology Task Force on standards for Infant Respiratory Function Testing whose aim is to provide guidelines for good laboratory practices according to the latest international recommendations. Application of such recommendations could be of particular value when attempting to develop standardized protocols in the scope of multi-centre trials. The first part resume these recommendations about apparatus, acquisition system and software for Infant Respiratory Function Testing. The second part focuses on physiological principles and practical considerations: calibration procedure, infant conditioning, tidal breathing measurements, and occlusion techniques for assessing passive respiratory mechanics, plethysmographic measurements of lung volume and airway resistance and forced expiratory flows measurements. The major problem when collecting lung function data is that of predicted values. Valid reference data, set up according to these recommendations, are, to date, still to be established. The last part of the document provides a review of the literature concerning infant respiratory function reference data and a resume of the most used of them. This document will clearly need to be updated regularly in response to advances in knowledge in this field.

DEPIVIH 2: Use of three HIV testing methods in French primary care settings - ELISA laboratory screening versus two rapid point-of-care HIV tests.

OBJECTIVE: The primary endpoint was to evaluate the use of HIV testing methods by French primary care providers: Elisa laboratory screening, instant result HIV diagnostic test and rapid result HIV diagnostic test. The secondary endpoints were the population screening rate of unknown HIV status consulting during the study period, reasons for screening and for choosing the specific screening method, the investigators' satisfaction with the rapid diagnostic test (RDT) and problems encountered. PATIENTS AND METHODS: National prospective interventional study with French family physicians (FP) from December 2013 to December 2014. FPs enrolled all consenting adults consulting for an HIV screening test during a 6-month period: the choice was an Elisa laboratory test or one of the two RDTs. RESULTS: During the study period, 43 FPs included 981 patients. HIV screening was performed for the first time for 31.6% of patients; 767 (78.2%) Elisa laboratory test prescriptions and 214 (21.8%) RDTs were performed, leading to a screening rate of 1.3%. For 120 (15.7%) of the Elisa laboratory tests, the result was not reported and six RDTs were not valid. Nine patients were diagnosed as HIV-infected (0.9%): five with Elisa laboratory test and four with RDT. Almost 90% of FPs were willing to keep on using RDTs in their daily practice. CONCLUSION: In general practice, RDTs may be an important additional tool to traditional HIV screening. They could account for one in five tests prescribed in this context.

[Cystic fibrosis: how to use pulmonary function tests]. / Mucoviscidose: du bon usage des explorations fonctionnelles respiratoires.

INTRODUCTION: Neonatal screening for cystic fibrosis (CF) leads to early dedicated specialist care for all patients. BACKGROUND: Pulmonary function tests (PFT) are mandatory for routine monitoring of CF patients. The aim of this article is to review the current guidelines for PFTs in CF, particularly the type of test, the age and the clinical status of the patient. VIEWPOINT: The regular use of spirometry is generally accepted. Many other tests are used but their clinical value in the routine follow-up of CF patients remains to be established. CONCLUSION: Further efforts should be made to evaluate the value of PFTs in CF, particularly in very young children.

A cluster-randomized trial to reduce major perinatal morbidity among women with one prior cesarean delivery in Québec (PRISMA trial): study protocol for a randomized controlled trial.

BACKGROUND: Rates of cesarean delivery are continuously increasing in industrialized countries, with repeated cesarean accounting for about a third of all cesareans. Women who have undergone a first cesarean are facing a difficult choice for their next pregnancy, i.e.: (1) to plan for a second cesarean delivery, associated with higher risk of maternal complications than vaginal delivery; or (b) to have a trial of labor (TOL) with the aim to achieve a vaginal birth after cesarean (VBAC) and to accept a significant, but rare, risk of uterine rupture and its related maternal and neonatal complications. The objective of this trial is to assess whether a multifaceted intervention would reduce the rate of major perinatal morbidity among women with one prior cesarean. METHODS/DESIGN: The study is a stratified, non-blinded, cluster-randomized, parallel-group trial of a multifaceted intervention. Hospitals in Quebec are the units of randomization and women are the units of analysis. As depicted in Figure 1, the study includes a 1-year pre-intervention period (baseline), a 5-month implementation period, and a 2-year intervention period. At the end of the baseline period, 20 hospitals will be allocated to the intervention group and 20 to the control group, using a randomization stratified by level of care. Medical records will be used to collect data before and during the intervention period. Primary outcome is the rate of a composite of major perinatal morbidities measured during the intervention period. Secondary outcomes include major and minor maternal morbidity; minor perinatal morbidity; and TOL and VBAC rate. The effect of the intervention will be assessed using the multivariable generalized-estimating-equations extension of logistic regression. The evaluation will include subgroup analyses for preterm and term birth, and a cost-effectiveness analysis. DISCUSSION: The intervention is designed to facilitate: (1) women's decision-making process, using a decision analysis tool (DAT), (2) an estimate of uterine rupture risk during TOL using ultrasound evaluation of low-uterine segment thickness, (3) an estimate of chance of TOL success, using a validated prediction tool, and (4) the implementation of best practices for intrapartum management. TRIAL REGISTRATION: Current Controlled Trials, ID: ISRCTN15346559 . Registered on 20 August 2015.

Acid dye adsorption onto cationized polyamide fibres. Modeling and consequent interpretations of model parameter behaviours.

Experimental adsorption isotherms of four acid dyes named Acid Blue 25, Acid Yellow 99, Reactive Yellow 23, and Acid Blue 74 from aqueous solution onto cationized nylon-6,6 have been analyzed using a double layer adsorption model. The parameters involved in the analytical expression of this model such as the number or fraction of adsorbed dye molecule per site, n, the number of receptor sites per gram of adsorbent, N(M), and the concentration at half-saturation, c1/2, are determined from adsorption isotherms at four temperatures between 293 and 353 K. The evolution of these parameters with temperature is discussed in relation with adsorption process and the behaviours of the different dyes taking into account their particular structure. The results are compared with those already published dealing with the adsorption of these same dyes onto cationized cotton. The configurational entropy at various temperatures has been studied. This parameter allowed to deduce some results related to the evolution of the disorder during the adsorption process.

Timing and driving components of the breathing strategy in children with cystic fibrosis during exercise.

The aim of this study was twofold: first, to determine the breathing strategies of children with cystic fibrosis (CF) during exercise, and secondly, to see if there was a correlation with lung function parameters. We determined the tension-time index of the inspiratory muscles (T(T0.1)) during exercise in nine children with CF, who were compared with nine healthy children with a similar age distribution. T(T0.1) was determined as followed T(T0.1) = P0.1/PImax . T(I)/T(TOT), where P0.1 is mouth occlusion pressure, PImax is maximal inspiratory pressure, and T(I)/T(TOT) is the duty cycle. CF children showed a significant decrease of their forced expiratory volume in 1 sec (FEV1), forced vital capacity (FCV), and FEV1/FVC, whereas the residual volume to total lung capacity ratio (RV/TLC) ratio and functional residual capacity (FRC) were significantly increased (P < 0.001). Children with CF showed mild malnutrition assessed by actual weight expressed by percentage of ideal weight for height, age, and gender (weight/height ratio; 82.3 +/- 3.6%). Children with CF showed a significant reduction in their PImax (69.3 +/- 4.2 vs. 93.8 +/- 7 cmH2O). We found a negative linear correlation between PImax and weight/height only in children with CF (r = 0.9, P < 0.001). During exercise, P(0.1), P0.1/PImax, and T(T0.1) were significantly higher, for a same percent maximal oxygen uptake in children with CF. On the contrary, T(I)/T(TOT) ratio was significantly lower in children with CF compared with healthy children. At maximal exercise, children with CF showed a T(T0.1) = 0.16 vs. 0.14 in healthy children (P < 0.001). We observed at maximal exercise that P0.1/PImax increased as FEV1/FVC decreased (r = -0.90, P < 0.001), and increased as RV/TLC increased (r = 0.92, P < 0.001) only in children with CF. Inversely, T(I)/T(TOT) decreased as FEV1/FVC decreased (r = 0.89, P < 0.001), and T(I)/T(TOT) decreased as RV/TLC increased (r = -0.94, P < 0.001). These results suggest that children with CF adopted a breathing strategy during exercise in limiting the increase of the duty cycle. Two determinants of this strategy were degrees of airway obstruction and hyperinflation.

Release of prostaglandins from the rabbit perfused kidney: effects of vasoconstrictors.

1 The rat stomach strip was used to assay prostaglandin E(2)-like material released by a rabbit isolated kidney perfused with Krebs solution.2 Doses of noradrenaline and angiotensin II producing similar vasoconstrictor effects released equivalent amounts of prostaglandins from the kidney.3 8-Leu-angiotensin II, a specific inhibitor of the natural octapeptide, blocked the action of angiotensin II on perfusion pressure and the release of prostaglandins, while the action of noradrenaline on both parameters was unaffected.4 Indomethacin, a specific inhibitor of prostaglandin biosynthesis, blocked the effects of both vasoconstrictors on prostaglandin release while their action on perfusion pressure was significantly enhanced.5 In the kidney effluent, amounts of prostaglandin E(2)-like material increased linearly with the rise in perfusion pressure induced by increasing doses of angiotensin II. These results indicate that prostaglandin output from the isolated kidney follows the rise in perfusion pressure.

Analysis of the behaviour of erythrocytes in an optical trapping system.

We present a theoretical analysis of the behaviour of erythrocytes in an optical trapping system. We modeled erythrocyte behaviour in an optical trap by an algorithm which divided the cell surface into a large number of elements and recursively summed the force and torque on each element. We present a relationship between the torque and angle of orientation of the cell, showing that stable equilibrium orientations are at angles of 0 o , 180 o and 360 o and unstable equilibrium orientations are at 90 o and 270 o relative to the axis of beam propagation. This is consistent with our experimental observations and with results described in the literature. We also model behaviour of the erythrocyte during micromanipulation by calculating the net force on it. Such theoretical analysis is practical as it allows for the optimization of the optical parameters of a trapping system prior to performing a specific optical micromanipulation application, such as cell sorting or construction of a cell pattern for lab-on-a-chip applications.

Single lung transplantation for cystic fibrosis: is it an option? Cystic Fibrosis Transplant Study Group.

A 15-year-old girl with end-stage lung disease from cystic fibrosis underwent a bilateral lung transplantation. Infarction of the left lung allograft required its removal on day 10. The patient went on to have an uneventful recovery except for a prolonged air leak from the right allograft of approximately 29 days. The left pleural cavity opacified with time with no clinical or radiologic evidence of empyema. The patient was discharged on day 35 in good condition. On a follow-up examination 6 months after transplantation, she appeared to be functioning extremely well with a single lung allograft. This case report challenges the conventional wisdom that bilateral pneumonectomy and single lung transplantation are not an option to be considered for patients with cystic fibrosis or bronchiectasis.

Maximal exercise capacity and peripheral skeletal muscle function following lung transplantation.

BACKGROUND: There have been many suggestions that diminished exercise capacity in patients that have undergone lung transplantation is due, in part, to peripheral muscle dysfunction, brought on by either detraining or immunosuppressive therapy. There is limited data quantifying skeletal muscle function in this population, especially in those more than 18 months post-procedure. The present study sought to quantitate skeletal muscle function and cardiopulmonary responses to graded exercise in 19 lung transplant recipients, 15 of which were mostly more than 18 months post-procedure. METHODS: Ten single- (SLT) and 9 double-lung transplantation (DLT) underwent anthropometric measures and performed expiratory spirometry, whole body plethysmography to assess lung volumes, static maximal mouth pressures to assess respiratory muscle strength, progressive exercise testing on a cycle ergometer (with cardiac output measurements being performed every second workload) and isokinetic cycling to assess peripheral muscle power and work capacity. RESULTS: The DLT group was younger than the SLT group (23.0 [21.0-32.0] vs 47.5 [43.0-55.0] median [interquartile range], p < .05) with no differences in height, weight, or BMI. Despite the DLT group having significantly better spirometric values (FEV1: 86% vs 56.5% median) and less airtrapping (RV/TLC: 30% vs 53.5%), both groups were equally limited in exercise capacity (Wmax)(38.0 percent predicted [30.0-65.0] vs 37.5 percent predicted [30.0-44.0], SLT vs DLT), leg power (76.1 percent predicted [53.8-81.4] vs 69.0 percent predicted [58.3-76.0]) and leg work capacity (63.3 percent predicted [34.7-66.8] vs 38.4 percent predicted [27.5-57.3]). This lack of difference in performance persisted when the analysis was limited to those more than 18 months post-procedure. Respiratory muscle strength was also not different for the two groups, and was within normal limits. Wmax was best correlated with leg work capacity (r = .84), but also with leg power, RV/TLC, FEV1 (r = .49, -.52, .58). When normalized for age, height, and sex, percent predicted Wmax only correlated with percent predicted leg work capacity (r = .58). Cardiac output was appropriate for the work performed. CONCLUSIONS: We conclude that peripheral skeletal muscle work capacity is reduced following lung transplantation and mostly responsible for the limitation of exercise performance. While the causes of muscular dysfunction have yet to be clarified, the preservation of respiratory muscle strength with the concomitant reduction in leg power and work capacity suggests that most of the muscular dysfunction post-transplantation is attributable to detraining.

Should we allow a trial of labor after a previous cesarean for dystocia in the second stage of labor?

OBJECTIVE: To estimate the rate of successful vaginal birth including operative vaginal delivery in patients with a previous cesarean for cephalopelvic disproportion in the second stage of labor. METHODS: Data from all patients who underwent trial of labor after a previous cesarean between 1990 and 2000 at our tertiary care institution were analyzed. Medical records were reviewed and data collected for the following variables: indication for the previous cesarean, birth weight and cervical dilatation at previous cesarean delivery, as well as the mode of delivery (spontaneous, vacuum, forceps, cesarean) and the birth weight for the subsequent pregnancy. Pearson's chi(2) test and one-way analysis of variance were used for statistical analyses. RESULTS: There were 2002 patients included in the study. Two hundred fourteen (11%) had their previous cesarean for dystocia in the second stage of labor, 654 (33%) for dystocia in the first stage of labor, and 1134 (57%) for other indications. The vaginal birth after cesarean success rate was 75.2% (P = .015 vs other indications), 65.6% (P < .001 vs other indications), and 82.5%, respectively. The rate of operative vaginal delivery was 15%, 12%, and 10% (P = .109). CONCLUSION: A trial of labor is reasonable in women whose previous cesarean was for dystocia in the second stage of labor. In this series, patients who underwent a trial of labor after a previous cesarean for dystocia in the second stage had 75.2% (95% confidence interval 69.5, 81.0) chance of achieving vaginal delivery.