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A novel spectroscopic approach for studying the flexibility and mobility in the hydrophobic interior of lipid bilayers at specific depths is proposed. A set of test compounds featuring an azido moiety and a cyano or carboxylic acid moiety, connected by an alkyl chain of different lengths, was synthesized. FTIR data and molecular dynamics calculations indicated that the test compounds in a bilayer are oriented so that the cyano or carboxylic acid moiety is located in the lipid head-group region, while the azido group stays inside the bilayer at the depth determined by its alkyl chain length. We found that the asymmetric stretching mode of the azido group (ν N3 ) can serve as a reporter of the membrane interior dynamics. FTIR and two-dimensional infrared (2DIR) studies were performed at different temperatures, ranging from 22 to 45 °C, covering the Lβ-Lα phase transition temperature of dipalmitoylphosphatidylcholine (∼41 °C). The width of the ν N3 peak was found to be very sensitive to the phase transition and to the temperature in general. We introduced an order parameter, S N3 , which characterizes restrictions to motion inside the bilayer. 2DIR spectra of ν N3 showed different extents of inhomogeneity at different depths in the bilayer, with the smallest inhomogeneity in the middle of the leaflet. The spectral diffusion dynamics of the N 3 peak was found to be dependent on the depth of the N 3 group location in the bilayer. The obtained results enhance our understanding of the bilayer dynamics and can be extended to investigate membranes with more complex compositions.

In patients visiting the emergency department (ED), a potential association between electrolytes disturbance and coronavirus disease 2019 (COVID-19) has not been well studied. We aim to describe electrolyte disturbance and explore risk factors for COVID-19 infection in patients visiting the ED. We carried out a case-control study in three hospitals in France, including adult ED inpatients (≥ 18 years old). A total of 594 ED case patients in whom infection with COVID-19 was confirmed, were matched to 594 non-COVID-19 ED patients (controls) from the same period, according to sex and age. Hyponatremia was defined by a sodium of less than 135 mmol/L (reference range 135-145 mmol/L), hypokalemia by a potassium of less than 3.5 mmol/L (reference range 3.5-5.0 mmol/L), and hypochloremia by a chloride of less than 95 mmol/L (reference range 98-108 mmol/L). Among both case patients and controls, the median (IQR) age was 65 years (IQR 51-76), and 44% were women. Hyponatremia was more common among case patients than among controls, as was hypokalemia and hypochloremia. Based on the results of the multivariate logistic regression, hyponatremia, and hypokalemia were associated with COVID-19 among case patients overall, with an adjusted odds ratio of 1.89 [95% CI 1.24-2.89] for hyponatremia and 1.76 [95% CI 1.20-2.60] for hypokalemia. Hyponatremia and hypokalemia are independently associated with COVID-19 infection in adults visiting the ED, and could act as surrogate biomarkers for the emergency physician in suspected COVID-19 patients., (© 2021. Società Italiana di Medicina Interna (SIMI).)

Background: We aimed to describe red blood cell (RBC) transfusions in the emergency department (ED) with a particular focus on the hemoglobin (Hb) level thresholds that are used in this setting., Methods: This was a cross-sectional study of 12 EDs including all adult patients that received RBC transfusion in January and February 2018. Descriptive statistics were reported. Logistic regression was performed to assess variables that were independently associated with a pre-transfusion Hb level ≥ 8 g/dL., Results: During the study period, 529 patients received RBC transfusion. The median age was 74 (59-85) years. The patients had a history of cancer or hematological disease in 185 (35.2%) cases. Acute bleeding was observed in the ED for 242 (44.7%) patients, among which 145 (59.9%) were gastrointestinal. Anemia was chronic in 191 (40.2%) cases, mostly due to vitamin or iron deficiency or to malignancy with transfusion support. Pre-transfusion Hb level was 6.9 (6.0-7.8) g/dL. The transfusion motive was not notified in the medical chart in 206 (38.9%) cases. In the multivariable logistic regression, variables that were associated with a higher pre-transfusion Hb level (≥8 g/dL) were a history of coronary artery disease (OR: 2.09; 95% CI: 1.29-3.41), the presence of acute bleeding (OR: 2.44; 95% CI: 1.53-3.94), and older age (OR: 1.02/year; 95% CI: 1.01-1.04)., Conclusion: RBC transfusion in the ED was an everyday concern and involved patients with heterogeneous medical situations and severity. Pre-transfusion Hb level was rather restrictive. Almost half of transfusions were provided because of acute bleeding which was associated with a higher Hb threshold.

Purpose In most industrialized countries, the share of workers in the age 55+ age group is increasing while there is a shortage of young workers. Although data suggest that at least one in five older workers suffers from chronic musculoskeletal pain, most will continue working despite pain. The objective of this study is to explore factors associated with staying at work for workers with musculoskeletal pain. Methods An interpretive descriptive method was used. Semi-structured individual interviews were conducted. Inclusion criteria were: manual/mixed occupations, persistent musculoskeletal pain, and working 28 h weekly or more. Analysis was performed using themes from the conceptual model created. Results Fourteen participants were included, ages 55-70. They ranged from self-employed individuals to employees of large organizations. For most, the perception of being useful, having peer recognition and feeling that work contributes to health were essential drivers for staying at work. Flexibility at work was deemed essential by all but took various forms. Individual cost of staying at work varied from low to high. Conclusion This study identified both personal and work-related factors associated with working in the presence of pain. New concept of cost of staying at work appears promising.

Background: Nasopharyngeal carcinoma (NPC) is a commonly diagnosed cancer in Southeast Asia. Many studies have examined the risk factors for NPC, yet the roles of some risk factors remain inconclusive. The purpose of this study was to examine associations between modifiable lifestyle factors and the risk of NPC in the Singaporean population., Methods: We conducted a case-control study in Singapore with 300 patients and 310 controls who were recruited between 2008 and 2012. Each control was selected and individually matched to each patient based on sex, ethnicity, and age (±5 years). A total of 290 pairs of cases and controls were matched successfully. We examined lifestyle factors such as tobacco smoking, alcohol drinking, various salted and preserved food consumption, and weaning practices., Results: After adjusting for covariates, multivariate analysis showed that those participants who were current smokers and had ever smoked tobacco had a higher risk of NPC than participants who had never smoked, with odds ratios (ORs) of 4.50 (95% confidence interval [CI] 2.58-7.86; P < 0.001) and 2.52 (95% CI 1.54-4.12; P < 0.001), respectively. Those who consumed salted vegetables at least once a week also showed a significantly increased risk of NPC than those who never or rarely consumed salted vegetables, with an OR of 4.18 (95% CI 1.69-10.38; P = 0.002)., Conclusion: Smoking (currently and ever-smoked) and consuming salted vegetables once a week or more were lifestyle risk factors for NPC, and changes of these factors for the better may reduce the risk of NPC.

This article examines the findings of an ecological analysis of the factors influencing men's engagement in intimate partner violence (IPV) groups. Individual interviews and two focus groups were conducted with men who participated in group programs in two agencies in Canada. Our qualitative analysis of interviews and focus groups suggested that both individual and program-related factors were determinants in the men's engagement. These findings drew our attention to the influence of certain factors outside of the group therapy, in particular organizational practices. Implications for practice are explored, in particular the role of time in the intervention, and implications for research and limitations are discussed.

DNA damage is a hazard all cells must face, and evolution has created a number of mechanisms to repair damaged bases in the chromosome. Paradoxically, many of these repair mechanisms can create double-strand breaks in the DNA molecule which are fatal to the cell. This indicates that the connection between DNA repair and death is far from straightforward, and suggests that the repair mechanisms can be a double-edged sword. In this report, we formulate a mathematical model of the dynamics of DNA damage and repair, and we obtain analytical expressions for the death rate. We predict a counterintuitive relationship between survival and repair. We can discriminate between two phases: below a critical threshold in the number of repair enzymes, the half-life decreases with the number of repair enzymes, but becomes independent of the number of repair enzymes above the threshold. We are able to predict quantitatively the dependence of the death rate on the damage rate and other relevant parameters. We verify our analytical results by simulating the stochastic dynamics of DNA damage and repair. Finally, we also perform an experiment with Escherichia coli cells to test one of the predictions of our model., (Copyright © 2011 Biophysical Society. Published by Elsevier Inc. All rights reserved.)

Purpose: The application of the margin of manoeuvre (MM) concept in work rehabilitation is new. It allows for variations in both health status and work demands, and the interaction between the two, to be taken into account. The objective of this exploratory study was to document the relationship between the presence of an MM in the workplace and the return to work (RTW), after a long-term absence., Methods: This study used the data collected during an earlier study that sought to identify the dimensions and indicators of the MM. The data were analysed on three levels, and the convergences and divergences in the MM indicators and dimensions in relation to the RTW were grouped accordingly., Results: Eleven workers and five clinicians participated in this study. The results support the proposition that the presence of a sufficient MM in the workplace is associated with RTW of individuals at the end of a rehabilitation programme despite a long-term absence (n = 6), and conversely, that its absence would appear to be associated with a non-return to work (n = 4)., Conclusions: A better understanding of this concept will help further the development of a tool to assist clinicians in their task of assessing a worker's capacity to return to a given job.

Objective: It is our standard of care to include pelvic lymph node dissection (PLND) in the staging of endometrial cancer, followed by adjuvant vaginal vault brachytherapy. We report our experience and outcome of patients with stage 1C grade 3 endometrial cancer from KK Hospital Singapore., Methods: Records of patients with a diagnosis of stage 1C grade 3 endometrial cancer (based on the 1988 FIGO [International Federation of Gynecology and Obstetrics] staging system) from 1995 to 2008 were retrospectively reviewed. Details of surgery, chemotherapy, and radiotherapy were recorded, as were prognostic factors such as histological subtype and number of lymph nodes removed. Dates and sites of relapses were noted., Results: A total of 31 cases were reviewed; 29 had sufficient records to be analyzed, of which one was excluded as she had a second primary cancer (breast). Median follow-up was 50.1 months (15.5-154 months). All cases underwent total hysterectomy and bilateral salpingo-oophorectomy; the majority (22 [76%]) had PLND as well. Those who did not undergo PLND received external beam radiotherapy instead. All but 1 case received postoperative vaginal vault brachytherapy. Eight of 10 patients with nonendometrioid adenocarcinoma (eg, clear cell) histology also received adjuvant chemotherapy. There were 5 systemic relapses (17.9%) and 1 pelvic recurrence (3.6%). The 5-year disease-free survival is 78.6%. No serious (grade 3 or 4) adverse effects were recorded., Conclusion: Pelvic lymph node dissection and vaginal vault brachytherapy seem to be effective in preventing locoregional recurrences, with few associated adverse effects. However, the rate of systemic relapse is relatively high. Adjuvant chemotherapy should also be considered for cases with poor prognostic factors.

Background and Objective: Platelets are essential for hemostasis, and they cause resistance to fibrinolysis by tissue-type plasminogen activator. In contrast, platelets enhance fibrinolysis mediated by single-chain urokinase-type plasminogen activator (scu-PA). This study investigated the mechanism behind this profibrinolytic role of platelets., Methods and Results: Platelets enhanced scu-PA activity, but not urokinase-type plasminogen activator (u-PA) activity, in plasma clot lysis and chromogenic assays. We established, using the non-cleavable scu-PA mutant (Lys158-->Glu) and protease inhibitors, that platelets increased activation to u-PA by a serine protease. Activation of scu-PA was platelet-dependent, even in plasma. It occurred in platelet-rich but not in platelet-poor plasma, as assessed by sodium dodecylsulfate polyacrylamide gel electrophoresis and zymography after addition of plasminogen activator inhibitor-1. Candidate proteases that are known to activate scu-PA and are present in platelet preparations were investigated. Factor VII activating protease was detected in platelet preparations by western blotting, but its inhibition by antibodies did not inhibit activation of scu-PA by platelets. Plasmin and plasma kallikrein both mimicked the platelet effect, but were distinguished by their responses to a range of inhibitors. Analysis of platelet-associated protease activity and the time course of scu-PA activation pointed towards plasminogen, and the data were consistent with a mechanism of reciprocal activation. The essential role of plasminogen was revealed using platelets from plasminogen-deficient mice, which could not activate scu-PA. Local plasminogen on platelet membranes was markedly more effective than solution-phase plasminogen in activation of scu-PA., Conclusions: Platelets enhance fibrinolysis by scu-PA through reciprocal activation of scu-PA and platelet-associated plasminogen, a system that is potentially important in the lysis of platelet-rich thrombi.

Introduction: The task of evaluating workers' capacity to return to their pre-injury employment or other jobs continues to pose a daily challenge for clinicians. In this study, a concept frequently used in the field of ergonomics, the margin of manoeuvre (MM), was applied during the rehabilitation process. The study identified the indicators of the MM taken into account during the return to work of workers with musculoskeletal disorders., Methods: This study used a multiple-case design. A case was defined as a dyad comprising a worker admitted to a work rehabilitation program and the clinician who was managing the return-to-work process. The results were then validated with investigators and expert ergonomists, through group interviews. Content analyses were performed using the conceptual framework for the work activity model adapted from Vézina and the procedures recommended by Miles and Huberman., Results: A total of 11 workers, five clinicians, two experts and two investigators participated in this study. The interview analysis process resulted in a more detailed definition of the MM and the identification of 50 indicators. The indicators were classified according to six dimensions: (1) work context; (2) employer's requirements and expectations; (3) means and tools; (4) worker's personal parameters; (5) work activity; and (6) impacts of the work situation., Conclusions: The more specific indicators identified in this study will allow for more systematic observation of the MM. Subsequent studies will seek to link each indicator described in the model with a specific method of observation.

Background: Despite the convergence of scientific data to the effect that interventions in the workplace promote a healthy return to work, the interventions carried out in the real work environment appear to be very heterogeneous and ill-defined., Objective: The goal of this review is to identify the different objectives pursued through the workplace interventions carried out in the context of a rehabilitation program, and to describe the activities involved., Methods: A descriptive review of the literature, including various research designs, was carried out., Results: This review reveals great heterogeneity in the content of interventions offered in the workplace to workers with musculoskeletal disabilities. The objectives of workplace interventions may range from gathering information in order to reproduce work demands in a clinical setting, to gradually exposing workers to the demands of the real work environment, or permanently reducing the demands of the work situation. A descriptive analysis of the literature also brings to light the diversity of actions carried out, human resources used, and workplace environments involved, while highlighting the few documented process outcome evaluations that have been done of workplace interventions., Conclusion: It is recommended that in future research in this area, efforts be made to better describe the components of the interventions, to develop process outcomes representing the multidimensional results obtained in the workplace, and to differentiate between temporary and permanent modifications made to the work situation.

Background: Conjunctival provocation tests (CPTs) are used for assessing the efficacy of antiallergic treatments, but their reproducibility is not well characterized. A study was carried out to assess the reproducibility of CPTs and the release of mediators during CPTs., Methods: Both eyes of 30 grass-pollen-allergic patients were challenged with threefold increasing concentrations of a standardized orchard grass pollen extract. The positivity of the CPT was assessed by a cumulative symptom score. The release of mediators was examined by means of histamine (radioimmunoassay), prostaglandin D2 and leukotrienes C4 and D4 (enzyme immunoassay)., Results: There was a significant correlation between the concentrations of allergen inducing a positive CPT in both eyes (p < 0.0001, Spearman). All but one patient had a significant release of at least one mediator. After allergen CPT there was a significant release in both eyes in 13 of 20 patients for prostaglandin D2, 11 of 19 for leukotrienes C4 and D4 and 15 of 18 for histamine. The correlations between the levels of mediators released during diluent and allergen challenges in both eyes were significant for prostaglandin D2 (diluent and allergen challenges) and leukotrienes C4 and D4 (allergen challenge)., Conclusion: Considering the whole group of patients, CPT is reproducible in both eyes, but the results are less satisfactory when patients are examined individually.

A case of deep seated lomboaortic lymph node enlargement, due to a storage hitiocytosis by fragments of polyethylene, draining the site of hip joint prosthesis is reported. These lymph node enlargement, made visible by tomodensitometry, were satellites of an ovarian adenocarcinoma. The artificial hip joint operation had taken place 17 years before and 10 years later the patient underwent a secondary operation to replace the prosthesis of the right hip. To the knowledge of the authors this is the first recorded case of lymph node enlargement due to a storage histiocytosis in response to debris shed from hip prosthesis being made visible by way of a radiological examination.

Studies in eucaryotic cells (mainly animals and yeast) indicate that at least two DNA polymerases are involved in DNA replication at the level of the replication fork: DNA polymerase alpha, which is associated with DNA primase, is involved in the replication of the lagging strand; DNA polymerase delta, associated with an exonuclease activity, synthesizes the forward continuous DNA strand. Much less information exists concerning plant systems. Previous work from this laboratory provided preliminary evidence of an association between DNA polymerase B from wheat embryo and an exonucleolytic activity. In this paper, we present additional data on the biochemical properties of DNA polymerase B. An improved purification procedure described in this article has been developed. During all the purification steps the nuclease activity was associated with DNA polymerase activity. A biochemical study of this enzyme activity shows that it is an exonuclease which hydrolyses DNA in the 3' to 5' direction. Moreover, this exonuclease confers a proofreading function to DNA polymerase B. Comparison of DNA polymerase B properties (template specificity, sensitivity to DNA replication inhibitors like aphidicolin and butyl-phenyl dGTP, copurification of DNA polymerase and exonuclease activities) with those of animal DNA polymerase delta indicates that these enzymes share many common features. To our knowledge, this is the first report of DNA polymerase delta in higher plants.

Eighteen patients with typical Herpes simplex virus dendritic keratitis confirmed by viral isolation were treated with corneal collagen shields presoaked with trifluorothymidine for 15 minutes and trifluorothymidine eye drops 5 times daily. The average healing time was 2.9 days (range 1-7 days). No allergic reactions were observed. Toxic punctate keratitis occurred in 3 eyes. The results of this open study suggest that the effect of collagen corneal shields in conjunction with trifluorothymidine shortens the average epithelial healing time compared with other studies that have used antiviral drugs alone.