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1.
Public Health ; 232: 138-145, 2024 Jul.
Article En | MEDLINE | ID: mdl-38776589

OBJECTIVES: The health service access point (PASS) allows people in precarious situations to benefit from medical and social care. A mobile PASS service was set up in 2020 in Marseille for people seeking asylum (DA). The objective of our study was to describe the care pathways within the PASS for DA. STUDY DESIGN: We led a retrospective observational study of care pathways of the 418 DA included in the PREMENTADA study (ClinicalTrials number: NCT05423782) in the 3 months following their inclusion. METHODS: We conducted a quantitative study, which ran from March 1, 2021, to August 31, 2021, to collect data from mobile and hospital PASS consultations, referrals following PASS consultations or hospitalizations, emergency room visits, hospitalizations, prescription, and dispensing of treatment following PASS consultations or on discharge from hospital, between D0 and M3. RESULTS: A total of 163 (39.0%) patients were lost to follow-up after an initial assessment of their health status. Overall, 74.4% of the patients were followed only by the mobile PASS for a mental health problem, and 57.4% were followed for a somatic problem until they obtained their rights. The mobile PASS referred 43.5% of patients to the hospital PASS for access to various technical facilities: medical imaging, pharmacy (63% of them benefited from the dispensing of health products), biological tests, and so on. The morbidities of the DAs were severe enough to require technical support that the mobile PASS could not provide, but recourse to the emergency department was fairly low (1.6%), testifying to the efficiency of the primary care provided by the mobile PASS. CONCLUSIONS: Our study provides the first data concerning the DA's healthcare pathway in France. Considering the health status of this population and the fact that early management of health problems allows for rationalization of costs, we can ask the question of the future of these patients in the absence of adapted care systems. The PASS and the hospitals to which they are attached will have to adapt their care offer to take into account the DA's specific problems.


Health Services Accessibility , Refugees , Humans , Refugees/statistics & numerical data , Female , Retrospective Studies , Male , Adult , Health Services Accessibility/statistics & numerical data , Middle Aged , Adolescent , Young Adult , France , Referral and Consultation/statistics & numerical data , Critical Pathways , Mobile Health Units/statistics & numerical data , Hospitalization/statistics & numerical data
3.
ESMO Open ; 8(6): 102031, 2023 Dec.
Article En | MEDLINE | ID: mdl-37879234

BACKGROUND: Despite increasing evidence on the safety of pregnancy after anticancer treatments in breast cancer survivors, many physicians and patients remain concerned about a potential risk of pregnancy specifically in the case of hormone receptor-positive breast cancer. MATERIALS AND METHODS: A systematic literature search of Medline, Embase and Cochrane library with no language or date restriction up to 31 March 2023 was carried out. To be included, articles had to be retrospective and prospective case-control and cohort studies as well as clinical trials comparing survival outcomes of premenopausal women with or without a pregnancy after prior diagnosis of hormone receptor-positive breast cancer. Disease-free survival (DFS) and overall survival (OS) were the outcomes of interest. Pooled hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated. Study protocol is registered in PROSPERO (n. CRD42023394232). RESULTS: Out of 7796 screened studies, 8 were eligible to be included in the final analysis. A total of 3805 patients with hormone receptor-positive invasive early breast cancer were included in these studies, of whom 1285 had a pregnancy after breast cancer diagnosis. Median follow-up time ranged from 3.8 to 15.8 years and was similar in the pregnancy and non-pregnancy cohorts. In three studies (n = 987 patients) reporting on DFS, no difference was observed between patients with and those without a subsequent pregnancy (HR 0.96, 95% CI 0.75-1.24, P = 0.781). In the six studies (n = 3504 patients) reporting on OS, patients with a pregnancy after breast cancer had a statistically significant better OS than those without a pregnancy (HR 0.46, 95% CI 0.27-0.77, P < 0.05). CONCLUSIONS: This systematic review and meta-analysis of retrospective cohort studies provides updated evidence that having a pregnancy in patients with prior history of hormone receptor-positive invasive early breast cancer appears safe without detrimental effect on prognosis.


Breast Neoplasms , Pregnancy , Humans , Female , Breast Neoplasms/drug therapy , Retrospective Studies , Disease-Free Survival , Proportional Hazards Models , Prognosis
4.
Chem Sci ; 13(45): 13563-13573, 2022 Nov 23.
Article En | MEDLINE | ID: mdl-36507175

Humans are estimated to consume several grams per week of nanoplastics (NPs) through exposure to a variety of contamination sources. Nonetheless, the effects of these polymeric particles on living systems are still mostly unknown. Here, by means of CD, NMR and TEM analyses, we describe at an atomic resolution the interaction of ubiquitin with polystyrene NPs (PS-NPs), showing how a hard protein corona is formed. Moreover, we report that in human HeLa cells exposure to PS-NPs leads to a sensible reduction of ubiquitination. Our study overall indicates that PS-NPs cause significant structural effects on ubiquitin, thereby influencing one of the key metabolic processes at the base of cell viability.

5.
Front Chem ; 10: 926364, 2022.
Article En | MEDLINE | ID: mdl-35958229

Chitosan-based hybrid nanocomposites, containing cellulose nanocrystals (CNCs), graphene oxide (GO), and borate as crosslinking agents, were successfully prepared by solution-casting technique. The synergistic effect of the two fillers, and the role of the cross-linker, in enhancing the structural and functional properties of the chitosan polymer, was investigated. XPS results confirm the chemical interaction between borate ions and hydroxyl groups of chitosan, GO, and CNCs. The morphological characterization shows that the GO sheets are oriented along the casting surface, whereas the CNC particles are homogenously distributed in the sample. Results of tensile tests reveal that the presence of graphene oxide enhances the elastic modulus, tensile strength, elongation at break, and toughness of chitosan, while cellulose and borate induce an increase in the elastic modulus and stress at the yield point. In particular, the borate-crosslinked chitosan-based sample containing 0.5 wt% of GO and 0.5 wt% of CNCs shows an elongation at a break value of 30.2% and a toughness value of 988 J*m-3 which are improved by 124% and 216%, respectively, compared with the pristine chitosan. Moreover, the water permeability results show that the presence of graphene oxide slightly increases the water barrier properties, whereas the borate and cellulose nanocrystals significantly reduce the water vapor permeability of the polymer by about 50%. Thus, by modulating the content of the two reinforcing fillers, it is possible to obtain chitosan-based nanocomposites with enhanced mechanical and water barrier properties which can be potentially used in various applications such as food and electronic packaging.

6.
Case Rep Hematol ; 2020: 8893185, 2020.
Article En | MEDLINE | ID: mdl-32908731

The occurrence of acute myeloid leukemia (AML) within six months from a diagnosis of breast cancer (BC) is rarely reported in the literature, and it is associated with a poor prognosis. We report herein the case of a 40-year-old woman referred to our centre affected by BC and simultaneous AML. The patient proved refractory to first line therapy and achieved complete remission (CR) with a clofarabine-based regimen followed by allogeneic stem cell transplantation (ASCT). Both during salvage chemotherapy and after ASCT, the patient presented severe infectious complications ( acute cholecistytis and Nocardia pneumonia, respectively) treated with surgery, and currently she is alive in CR for both diseases after 29 months of follow-up. The case highlights the importance of a diagnostic assessment of any unexplained cytopenia in association with solid neoplasia under treatment, underlining the feasibility and priority of a timely treatment of the haematological neoplasm in order to achieve long-term survival.

8.
BMC Med Inform Decis Mak ; 20(1): 34, 2020 02 19.
Article En | MEDLINE | ID: mdl-32075633

BACKGROUND: Despite the established evidence and theoretical advances explaining human judgments under uncertainty, developments of mobile health (mHealth) Clinical Decision Support Systems (CDSS) have not explicitly applied the psychology of decision making to the study of user needs. We report on a user needs approach to develop a prototype of a mHealth CDSS for Parkinson's disease (PD), which is theoretically grounded in the psychological literature about expert decision making and judgement under uncertainty. METHODS: A suite of user needs studies was conducted in 4 European countries (Greece, Italy, Slovenia, the UK) prior to the development of PD_Manager, a mHealth-based CDSS designed for Parkinson's disease, using wireless technology. Study 1 undertook Hierarchical Task Analysis (HTA) including elicitation of user needs, cognitive demands and perceived risks/benefits (ethical considerations) associated with the proposed CDSS, through structured interviews of prescribing clinicians (N = 47). Study 2 carried out computational modelling of prescribing clinicians' (N = 12) decision strategies based on social judgment theory. Study 3 was a vignette study of prescribing clinicians' (N = 18) willingness to change treatment based on either self-reported symptoms data, devices-generated symptoms data or combinations of both. RESULTS: Study 1 indicated that system development should move away from the traditional silos of 'motor' and 'non-motor' symptom evaluations and suggest that presenting data on symptoms according to goal-based domains would be the most beneficial approach, the most important being patients' overall Quality of Life (QoL). The computational modelling in Study 2 extrapolated different factor combinations when making judgements about different questions. Study 3 indicated that the clinicians were equally likely to change the care plan based on information about the change in the patient's condition from the patient's self-report and the wearable devices. CONCLUSIONS: Based on our approach, we could formulate the following principles of mHealth design: 1) enabling shared decision making between the clinician, patient and the carer; 2) flexibility that accounts for diagnostic and treatment variation among clinicians; 3) monitoring of information integration from multiple sources. Our approach highlighted the central importance of the patient-clinician relationship in clinical decision making and the relevance of theoretical as opposed to algorithm (technology)-based modelling of human judgment.


Clinical Decision-Making , Decision Support Systems, Clinical , Health Personnel/psychology , Parkinson Disease/prevention & control , Telemedicine , Greece , Humans , Italy , Judgment , Models, Theoretical , Psychological Theory , Slovenia , United Kingdom
9.
Carbohydr Polym ; 231: 115772, 2020 Mar 01.
Article En | MEDLINE | ID: mdl-31888830

Cystalline-Cc and ultra-milled Amorphous-Ca cellulose were used as reactive filler to tune the performances of composite polyurethane-cellulose-foams, PUC. The effect of Cc and Ca on chemo-physical and mechanical properties of PUC was analysed through FTIR, morphological analysis, thermal conductivity and compression measurements. FTIR results show that, both Cc and Ca react with isocyanate through the OH functional groups contributing to the formation of a tough cellulose-polyurethane network. Morphological observations show that the addition of both Cc and Ca induces a decrease of average cell-size compared to the pristine-PU, thus confirming that they act as nucleating agent. In addition, the better dispersion of the Ca in the polyol, with respect to Cc induces, a finer cell leading to a reduction of the thermal conductivity around 33 % (for the composite loaded with 20 %wt-Ca) with respect to pristine-PU. Finally, the addition of Ca highly reactive modifies the mechanical behaviour from rigid-brittle to semi-rigid.

10.
Forensic Sci Int Genet ; 44: 102206, 2020 01.
Article En | MEDLINE | ID: mdl-31765878

We present the results obtained on DNA extracted from ocular (scleral/corneal) swabs collected from exhumed bodies at different times of burial. To our knowledge, there are no publications in the scientific forensic literature dealing with sclera/cornea as a source of DNA in the forensic laboratory. The obtained results demonstrate that cornea/sclera swabbing might be a promising alternative to the sampling of other tissues for DNA extraction even in highly putrefied bodies.


Cornea/chemistry , DNA/isolation & purification , Exhumation , Sclera/chemistry , Specimen Handling/methods , Body Remains , DNA Fingerprinting , Forensic Genetics/methods , Humans , Microsatellite Repeats , Polymerase Chain Reaction
11.
Med Mal Infect ; 50(8): 689-695, 2020 Nov.
Article En | MEDLINE | ID: mdl-31759689

OBJECTIVES: We aimed to assess the incidence of respiratory tract infections in military settings between 2006 and 2015. PATIENTS AND METHODS: We performed a retrospective epidemiological study of the entire military population from 2006 to 2015. Comprehensive data was collected from all medical centers, operational medical units, naval services, and army training hospitals and provided by the epidemiological surveillance of the armies. RESULTS: The annual average population of the study was 331,394 soldiers. For acute respiratory tract infections (2006-2015), 22,818 cases were reported in metropolitan France, 3,211 cases in French overseas territories, 1,595 cases in the French Navy, and 1,318 cases in external military operations for a total of 28,942 cases. For influenza (2006-2013), 934 cases were reported in metropolitan France, 101 cases in French overseas territories, and 23 cases in external operations, for a total of 1,058 cases. The mean incidence rate of acute respiratory tract infections expressed as case number per 1,000 person-years (PY) was 8.7 PY (95% CI [8.6-8.8]) with an exceptional increased incidence rate in 2009 (25.9 PY, 95% CI [25.4-26.4]). The mean incidence rate of influenza was 0.35 PY (95% CI [0.33-0.37]) with a peak incidence rate of 1.9 PY in 2009. CONCLUSION: Acute respiratory tract infections are at the forefront of infectious episodes in the French armies. Although not necessarily severe, current prevention measures are not enough to reduce the incidence threshold of these infections and need to be improved.


Communicable Diseases , Influenza, Human , Military Personnel , Humans , Incidence , Influenza, Human/epidemiology , Retrospective Studies
12.
J Appl Microbiol ; 127(3): 618-629, 2019 Sep.
Article En | MEDLINE | ID: mdl-30848509

The aims of this study were: (i) the characterization of the structure of the indigenous microbial community associated with the sediments under study; (ii) the isolation and characterization of microbial consortia able to degrade the aged hydrocarbons contaminating the sediments, and (iii) the assessment of related biodegradation capability of selected consortia. Samples of surface sediments were collected in Priolo Gargallo harbour (Sicily, Italy). The samples were analysed for physical, chemical (GC-FID analysis) and microbiological characteristics (qualitative (16S rDNA clone library) and quantitative (DAPI, CFU and MPN count) analysis). The sediment samples were used for the selection of two microbial consortia (indicated as PSO and PSM) with high biodegradation capacity for crude oil (∼95%) and PAHs (∼63%) respectively. Genetic analysis showed that Alcanivorax and Cycloclasticus were the dominant genera in both the PSO and PSM consortia. Oil-polluted environments naturally develop an elevated biorecovery potential. The presence of a highly specialized microbial flora (adapted to support the contamination) and their stimulation through favourable induced conditions provides a promising recovery strategy. The chance to identify and select indigenous bacteria and/or consortia with a high biodegradation capacity is fundamental for the development and optimization of bioaugmentation strategies especially for those concerning in situ applications.


Bacteria/metabolism , Geologic Sediments/microbiology , Hydrocarbons/metabolism , Microbial Consortia , Water Pollutants, Chemical/metabolism , Bacteria/isolation & purification , Biodegradation, Environmental , Gammaproteobacteria/isolation & purification , Geologic Sediments/chemistry , Italy , Petroleum/metabolism , Petroleum Pollution , Polycyclic Aromatic Hydrocarbons/metabolism
13.
Clin Ter ; 169(6): e261-e264, 2018.
Article En | MEDLINE | ID: mdl-30554243

In pathological-forensic literature blast injuries are usually studied in relation to suicides, homicides during terroristic attacks and accidental events on the workplace, while the finding of these kinds of fatalities during misdoing is a recent occurrence. The Authors describe the peculiar case of the accidental death of the member of a criminal mob specialized in thefts to ATMs using acetylene tanks. The victim, having poured out the acetylene with the intent of triggering an explosion, was involved in the blast of the tank, deceasing immediately. This unusual manner of death highlights the danger of room saturation with acetylene, a criminal technique becoming more and more popular in the last years.


Acetylene/toxicity , Blast Injuries/pathology , Explosions , Accidents , Adult , Blast Injuries/etiology , Humans , Male , Theft
14.
Forensic Sci Int ; 289: 150-153, 2018 Aug.
Article En | MEDLINE | ID: mdl-29864601

Congo Red staining is usually used in diagnosing amyloidosis, a pathology characterized by the storage of abnormal proteins in several human organs. When assessed on samples fixated in formalin and embended in paraffin, this staining can undergo several artefacts, causing diagnostic and interpretative difficulties due to its weak stainability and a consequent reduced visibility of the amyloid. These complications, in time, requested several variations of this staining technique, especially in clinical practice, while in the forensic field no protocols has ever been adapted to cadaveric samples, a material that is already characteristically burdened by a peculiar stainability. In our work, studying a sudden death caused by cardiac amyloidosis and diagnosed only with post-mortem exams, we present a modified Congo Red staining used with the purpose to demonstrate amyloid in cadaveric material after the unsuccessfully use of all standard protocols.


Amyloidosis/pathology , Coloring Agents , Congo Red , Heart Diseases/pathology , Myocardium/pathology , Staining and Labeling/methods , Aged, 80 and over , Female , Forensic Pathology/methods , Humans , Microscopy
15.
Clin. microbiol. infect ; 23(12)Dec. 2017.
Article En | BIGG | ID: biblio-947860

SCOPE: Hepatitis B virus (HBV) infection reactivation is associated with high morbidity and mortality in patients with haematologic malignancy and/or haematopoietic stem cell transplantation (HSCT). However, information on this issue is limited. The scope of this position paper is to provide recommendations on HBV screening, monitoring, prophylaxis, treatment and vaccination in the patients described above. METHODS: These recommendations were developed from one meeting of experts attended by different Italian scientific societies as well as from a systematic literature review (of articles published through December 31, 2016) on HBV infection in haematologic patients and in patients who underwent haematopoietic stem cell transplantation published in the same issue of the journal. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology was used to assess each recommendation's quality. QUESTIONS ADDRESSED: These recommendations provide the answers to the following questions: (a) HBV screening and monitoring: Who should be screened before chemotherapy? Which screening tests should be used? Should HBV-DNA detection be used to monitor HBV reactivation before starting antivirals? What is the best timeline to monitor HBV reactivation? (b) Prophylaxis in HBsAg-positive patients: Which antiviral drugs should be used to treat HBsAg-positive patients? How long should antiviral prophylaxis be provided to HBsAg-positive patients? (c) Prophylaxis in patients with resolved HBV infection: Which patients with resolved HBV infection should receive antiviral prophylaxis? Which antiviral drug should be used? How long should antiviral prophylaxis be provided? (d) HBV infection management strategy in autologous (auto-HSCT) and allogeneic HSCT (allo-HSCT): Which HSCT recipients should receive antiviral prophylaxis? Which antiviral drug should be used? How long should antiviral prophylaxis be provided? (e) Choice of antiviral drugs in the treatment of HBV reactivation: Should third-generation anti-HBV drugs be preferred to first- or second-generation antiviral drugs in the treatment of HBV reactivation with or without hepatitis flare in haematologic patients? (f) Immunization against HBV in patients with haematologic malignancies and/or patients who underwent HSCT: Should these patients be vaccinated? Which HBV vaccination schedule should be adopted? RECOMMENDATIONS: Haematologic patients should be screened for hepatitis B surface antigen (HBsAg) plus anti-hepatitis B core protein (HBc), and HBV DNA before chemotherapy. HBV DNA levels should be monitored monthly in all HBV-positive patients who do not receive prophylaxis. HBsAg-positive haematologic patients and those undergoing HSCT should receive third-generation antiviral therapy as prophylaxis. Anti-HBc-positive lymphoma patients and those receiving HSCT should receive antiviral prophylaxis. All HBV-negative haematologic patients should be vaccinated for HBV. The acquisition of data from well-designed studies is desirable in the near future.


Humans , Antiviral Agents/therapeutic use , Virus Activation , Hematopoietic Stem Cell Transplantation , Hematologic Neoplasms/complications , Hepatitis B/prevention & control , Recurrence , Hepatitis B/diagnosis , Hepatitis B/drug therapy
16.
Clin Microbiol Infect ; 23(12): 916-923, 2017 Dec.
Article En | MEDLINE | ID: mdl-28668465

BACKGROUND: The growth of new therapeutic options and practices increases the risk of hepatitis B virus (HBV) reactivation in patients with haematologic malignancies and/or patients undergoing haematologic stem cell transplantation (HSCT). OBJECTIVES: To provide a systematic review supporting recommendations for prevention, monitoring, prophylaxis and therapy of HBV reactivation in patients with haematologic malignancies and HSCT. DATA SOURCES: The systematic review was based on a strategy using PubMed and the Cochrane Library searching literature published from 1991 to December 31, 2016. PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guidelines were followed. SELECTION CRITERIA: Randomized control trials, prospective and retrospective cohort studies. RISK-OF-BIAS ASSESSMENT: Cochrane Risk of Bias Tool and Newcastle Ottawa Quality Assessment Scale. RESULTS: Forty-two studies of fair or good quality were included in this systematic review. The following main results were obtained: haematologic patients should be screened for HBV before chemotherapy; HBV DNA levels should be monthly monitored in all HBV-positive patients not receiving prophylaxis; hepatitis B surface antigen (HBsAg)-positive haematologic patients and patients undergoing HSCT should receive prophylaxis and third-generation HBV drugs should be provided; and anti-hepatitis B core protein-positive lymphoma patients and patients who underwent HSCT should receive antiviral prophylaxis. CONCLUSIONS: A higher quality of evidence is needed. However, the level of evidence was sufficient to support the recommendations published in this issue of the journal.


Hematologic Neoplasms/complications , Hematopoietic Stem Cell Transplantation/adverse effects , Hepatitis B/diagnosis , Virus Activation , Antiviral Agents/therapeutic use , Hematologic Neoplasms/virology , Hepatitis B/drug therapy , Hepatitis B/prevention & control , Humans , Recurrence , Secondary Prevention , Virus Activation/drug effects
17.
Clin Microbiol Infect ; 23(12): 935-940, 2017 Dec.
Article En | MEDLINE | ID: mdl-28668466

SCOPE: Hepatitis B virus (HBV) infection reactivation is associated with high morbidity and mortality in patients with haematologic malignancy and/or haematopoietic stem cell transplantation (HSCT). However, information on this issue is limited. The scope of this position paper is to provide recommendations on HBV screening, monitoring, prophylaxis, treatment and vaccination in the patients described above. METHODS: These recommendations were developed from one meeting of experts attended by different Italian scientific societies as well as from a systematic literature review (of articles published through December 31, 2016) on HBV infection in haematologic patients and in patients who underwent haematopoietic stem cell transplantation published in the same issue of the journal. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology was used to assess each recommendation's quality. QUESTIONS ADDRESSED: These recommendations provide the answers to the following questions: (a) HBV screening and monitoring: Who should be screened before chemotherapy? Which screening tests should be used? Should HBV-DNA detection be used to monitor HBV reactivation before starting antivirals? What is the best timeline to monitor HBV reactivation? (b) Prophylaxis in HBsAg-positive patients: Which antiviral drugs should be used to treat HBsAg-positive patients? How long should antiviral prophylaxis be provided to HBsAg-positive patients? (c) Prophylaxis in patients with resolved HBV infection: Which patients with resolved HBV infection should receive antiviral prophylaxis? Which antiviral drug should be used? How long should antiviral prophylaxis be provided? (d) HBV infection management strategy in autologous (auto-HSCT) and allogeneic HSCT (allo-HSCT): Which HSCT recipients should receive antiviral prophylaxis? Which antiviral drug should be used? How long should antiviral prophylaxis be provided? (e) Choice of antiviral drugs in the treatment of HBV reactivation: Should third-generation anti-HBV drugs be preferred to first- or second-generation antiviral drugs in the treatment of HBV reactivation with or without hepatitis flare in haematologic patients? (f) Immunization against HBV in patients with haematologic malignancies and/or patients who underwent HSCT: Should these patients be vaccinated? Which HBV vaccination schedule should be adopted? RECOMMENDATIONS: Haematologic patients should be screened for hepatitis B surface antigen (HBsAg) plus anti-hepatitis B core protein (HBc), and HBV DNA before chemotherapy. HBV DNA levels should be monitored monthly in all HBV-positive patients who do not receive prophylaxis. HBsAg-positive haematologic patients and those undergoing HSCT should receive third-generation antiviral therapy as prophylaxis. Anti-HBc-positive lymphoma patients and those receiving HSCT should receive antiviral prophylaxis. All HBV-negative haematologic patients should be vaccinated for HBV. The acquisition of data from well-designed studies is desirable in the near future.


Hematologic Neoplasms/complications , Hematopoietic Stem Cell Transplantation/adverse effects , Hepatitis B/diagnosis , Virus Activation , Antiviral Agents/therapeutic use , Hematologic Neoplasms/virology , Hepatitis B/drug therapy , Hepatitis B/prevention & control , Humans , Recurrence , Secondary Prevention , Virus Activation/drug effects
18.
Eur J Vasc Endovasc Surg ; 54(2): 254-263, 2017 Aug.
Article En | MEDLINE | ID: mdl-28655506

OBJECTIVE/BACKGROUND: The development of ascending aortic dilatation in patients with bicuspid aortic valve (BAV) is highly variable, and this makes surgical decision strategies particularly challenging. The purpose of this study was to identify new predictors, other than the well established aortic size, that may help to stratify the risk of aortic dilatation in BAV patients. METHODS: Using fluid-structure interaction analysis, both haemodynamic and structural parameters exerted on the ascending aortic wall of patients with either BAV (n = 21) or tricuspid aortic valve (TAV; n = 13) with comparable age and aortic diameter (42.7 ± 5.3 mm for BAV and 45.4 ± 10.0 mm for TAV) were compared. BAV phenotypes were stratified according to the leaflet fusion pattern and aortic shape. RESULTS: Systolic wall shear stress (WSS) of BAV patients was higher than TAV patients at the sinotubular junction (6.8 ± 3.3 N/m2 for BAV and 3.9 ± 1.3 N/m2 for TAV; p = .006) and mid-ascending aorta (9.8 ± 3.3 N/m2 for BAV and 7.1 ± 2.3 N/m2 for TAV; p = .040). A statistically significant difference in BAV versus TAV was also observed for the intramural stress along the ascending aorta (e.g., 2.54 × 105 ± 0.32 × 105 N/m2 for BAV and 2.04 × 105 ± 0.34 × 105 N/m2 for TAV; p < .001) and pressure index (0.329 ± 0.107 for BAV and 0.223 ± 0.139 for TAV; p = .030). Differences in the BAV phenotypes (i.e., BAV type 1 vs. BAV type 2) and aortopathy (i.e., isolated tubular vs. aortic root dilatations) were associated with asymmetric WSS distributions in the right anterior aortic wall and right posterior aortic wall, respectively. CONCLUSION: These findings suggest that valve mediated haemodynamic and structural parameters may be used to identify which regions of aortic wall are at greater stress and enable the development of a personalised approach for the diagnosis and management of aortic dilatation beyond traditional guidelines.


Aorta/physiopathology , Aortic Aneurysm/physiopathology , Aortic Valve/abnormalities , Heart Valve Diseases/physiopathology , Hemodynamics , Aged , Aorta/diagnostic imaging , Aortic Aneurysm/diagnostic imaging , Aortic Aneurysm/etiology , Aortic Valve/diagnostic imaging , Aortic Valve/physiopathology , Aortography/methods , Bicuspid Aortic Valve Disease , Blood Flow Velocity , Computed Tomography Angiography , Dilatation, Pathologic , Female , Heart Valve Diseases/complications , Heart Valve Diseases/diagnostic imaging , Humans , Male , Middle Aged , Models, Cardiovascular , Patient-Specific Modeling , Regional Blood Flow , Risk Factors , Stress, Mechanical
19.
Soft Matter ; 13(8): 1654-1659, 2017 Feb 22.
Article En | MEDLINE | ID: mdl-28138668

Organic-inorganic perovskites are semiconductors used for applications in optoelectronics and photovoltaics. Micron and submicron perovskite patterns have been explored in semitransparent photovoltaic and lasing applications. In this work, we show that a polymeric medium can be used to create a patterned perovskite, by using a novel and inexpensive approach.

20.
Chaos ; 26(8): 083108, 2016 Aug.
Article En | MEDLINE | ID: mdl-27586604

We consider parametrically forced Hamiltonian systems with one-and-a-half degrees of freedom and study the stability of the dynamics when the frequency of the forcing is relatively high or low. We show that, provided the frequency is sufficiently high, Kolmogorov-Arnold-Moser (KAM) theorem may be applied even when the forcing amplitude is far away from the perturbation regime. A similar result is obtained for sufficiently low frequency, but in that case we need the amplitude of the forcing to be not too large; however, we are still able to consider amplitudes which are outside of the perturbation regime. In addition, we find numerically that the dynamics may be stable even when the forcing amplitude is very large, well beyond the range of validity of the analytical results, provided the frequency of the forcing is taken correspondingly low.

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