Color and flexural properties of nanoparticles-modified denture base resin: An in vitro comparative study.

Objectives: Reinforcement of polymethylmethacrylate (PMMA) denture base resins (DBRs) with inorganic fillers with superior properties and accepted aesthetics are favored and still a big dilemma. This study was undertaken to evaluate the color change, flexural strength, and modulus of elasticity of heat-polymerized DBR material modified with silver nanoparticles (AgNPs) and zirconium dioxide nanoparticles (ZNPs). Methods: Sixty acrylic specimens (30/color test, 30/flexural properties) were fabricated and divided according to nanoparticles type and addition into 3 groups (n = 10). Group-I; unmodified specimens, Group-II; modified specimens with 0.5wt% AgNPs (PMMA/AgNPs), and Group-III; modified specimens with 7.5wt% ZNPs (PMMA/ZNPs). Disc-shape (20 × 3 mm) and bar-shape (65 × 10 × 2.5 mm) specimens were fabricated for color and flexural properties, respectively. The spectrophotometer was used for evaluation of the color change (∆E). The flexural strength and elastic modulus evaluation was carried out using a 3-point bending test (5 mm/min). Tukey's post hoc and one-way ANOVA were used to analyze the data at a significant level P ≤ 0.05. Results: PMMA/AgNPs group exhibited a significant increase in color change when compared with PMMA/ZNPs. PMMA/ZNPs showed significantly the highest flexural strength value when compared with unmodified and PMMA/AgNPs groups (P < 0.001), however, there was an absence of significant differences in terms of flexural strength values between PMMA/AgNPs and unmodified groups (P > 0.05). PMMA/AgNPs insignificantly increased its modulus of elasticity strength (P = 0.09410) while PMMA/ZNPs significantly increased its modulus of elasticity strength (P = 0.00396). Conclusion: The AgNPs and ZNPs addition to PMMA increased the color change and AgNPs change the color of DBRs. The flexural attributes of DBRs have been increased by ZNPs.

Menopausal hormone therapy and risk of venous thromboembolism: The story so far.

Menopausal hormone therapy (MHT) is known to increase the risk of venous thromboembolism (VTE), which includes deep vein thrombosis, pulmonary embolism, and less frequently cerebral vein thrombosis, but the absolute risk for a given patient is very low. After starting MHT, the risk of VTE seems to be at its highest, declining to the non-HRT user baseline level of risk after stopping. Whether estrogen-only or estrogen-progestin HRT combination is linked to a similar risk of VTE is unclear from the available evidence. The aim of this study is to evaluate the risks of developing VTE in relation to different types as well as different modes of administration of MHT through a database search including PubMed, MEDLINE, Google Scholar, Cochrane Library, and others in order to provide the women carers with the up-to-date and evidence-based guidelines and recommendations while counseling the post-menopausal women enquiring on use of hormonal therapies either to alleviate the menopausal symptoms or to prevent the long-term sequelae of estrogen deficiency.

On sait que l'hormonothérapie ménopausique (MHT) augmente le risque de thromboembolie veineuse (TEV), qui comprend la thrombose veineuse profonde, l'embolie pulmonaire et, moins fréquemment, la thrombose veineuse cérébrale, mais le risque absolu pour un patient donné est très faible. Après le début du MHT, le risque de TEV semble être à son plus haut niveau, diminuant jusqu'au niveau de risque de base des non-utilisatrices de THS après l'arrêt. Les preuves disponibles ne permettent pas de savoir si un THS à base d'œstrogène seul ou d'association œstroprogestative est lié à un risque similaire de TEV. Le but de cette étude est d'évaluer les risques de développer une TEV par rapport à différents types ainsi qu'à différents modes d'administration du MHT grâce à une recherche dans des bases de données comprenant PubMed, MEDLINE, Google Scholar, Cochrane Library et autres afin de fournir aux femmes les soignants avec les lignes directrices et recommandations à jour et fondées sur des preuves tout en conseillant les femmes ménopausées qui se renseignent sur l'utilisation de thérapies hormonales, soit pour soulager les symptômes de la ménopause, soit pour prévenir les séquelles à long terme d'une carence en œstrogènes.

Effect of Production Bias on Radiation-Induced Segregation in Ni-Cr Alloys.

We present an in-depth investigation into the Radiation-Induced Segregation (RIS) phenomenon in Ni-Cr alloys. All the pivotal factors affecting RIS such as surface's absorption efficiency, grain size, production bias, dose rate, temperature, and sink density were systematically studied. Through comprehensive simulations, the individual and collective impacts of these factors were analyzed, enabling a refined understanding of RIS. A notable finding was the significant influence of production bias on point defects' interactions with grain boundaries/surfaces, thereby playing a crucial role in RIS processes. Production bias alters the neutrality of these interactions, leading to a preferential absorption of one type of point defect by the boundary and consequent establishment of distinct surface-mediated patterns of point defects. These spatial patterns further result in non-monotonic spatial profiles of solute atoms near surfaces/grain boundaries, corroborated by experimental observations. In particular, a positive production bias, signifying a higher production rate of vacancies over interstitials, drives more Cr depletion at the grain boundary. Moreover, a temperature-dependent production bias must be considered to recover the experimentally reported dependence of RIS on temperature. The severity of radiation damage and RIS becomes more pronounced with increased production bias, dose rate, and grain size, while high temperatures or sink density suppress the RIS severity. Model predictions were validated against experimental data, showcasing robust qualitative and quantitative agreements. The findings pave the way for further exploration of these spatial dependencies in subsequent studies, aiming to augment the comprehension and predictability of RIS processes in alloys.

Venous thromboembolism and pregnancy: A review of the literature.

This review aims to provide the mother carers with the most recent evidence-based guidelines in the context of managing of pregnancy-associated VTE, where an extensive search through the medical journals addressing the topic including the medical database such as Pubmed, Medline, Sience direct,Embase and others using the title and key-words in order to gather the most concerned as well as the up-to-date publications concerned with the problem under research, the search resulted in recognising pregnancy as a significant risk factor for the development of VTE, both during the prenatal and postnatal periods, with an estimated increased likelihood risk of five and sixty times, respectively and concluded that venous thromboembolism (VTE) is one of the leading causes of maternal mortality hence, all pregnant women should be assessed for the risk of developing the condition as early as possible (when scheduling a booking antenatal appointment) or even in the pre-pregnancy clinic.

Purkinje-Related Ventricular Tachycardia and Ventricular Fibrillation: Solved and Unsolved Questions.

Of the monomorphic ventricular tachycardias, there are 4 specific tachycardias related to the Purkinje system: 1) idiopathic verapamil-sensitive fascicular ventricular tachycardia (FVT); 2) non-re-entrant FVT; 3) bundle branch re-entry and interfascicular re-entry; and 4) Purkinje-mediated VT in structural heart disease. Verapamil-sensitive FVT is classified into 4 types according to the location of the circuit: 1) left posterior type; 2) left anterior type; 3) left upper septal type;and 4) reverse type. And, in the left anterior and posterior types, there are septal and papillary muscle subtypes. Although macro-re-entry has been reported to be the mechanism underlying verapamil-sensitive FVT, recording the entire circuit is challenging. One possible reason is that the Purkinje-muscle junction may penetrate the myocardial layer as a part of the circuit. The Purkinje network may thus play an important role in the initiation and maintenance of ventricular fibrillation. Further, it has been reported that the development and the abnormalities of the Purkinje system are associated with the arrhythmogenesis of ventricular fibrillation. Furthermore, it has been reported that catheter ablation of trigger ventricular premature complexes, and/or "de-networking" of the Purkinje system, can be used as electrical bailout therapy. There is a hypothesis that the intramural Purkinje system is involved in the generation of J waves. Nevertheless, as there are still unresolved issues that must be debated and accurately analyzed, this review aims to discuss the solved and unsolved questions related to Purkinje-related arrhythmias.

Impetigo herpetiformis: A rare pregnancy-specific dermatosis.

Impetigo herpetiformis (IH) is a pregnancy-specific dermatosis that is currently considered a form of generalised pustular psoriasis and mainly occurs in late pregnancy during the third trimester. IH presents as erythematous patches and pustules and might have systemic involvement. The disease may be associated with severe maternal, fetal, and neonatal complications. IH treatment is very challenging, however, various therapeutic options are available and effective for disease treatment.

Intrahepatic cholestasis of pregnancy: from an obstetrician point of view.

Intrahepatic cholestasis of pregnancy (ICP) is the commonest among the specific dermatoses of pregnancy. The disease is characterised by intense pruritus and specifically by elevated bile acid levels and owing to the rarity of data published in this context, the disease carries a great challenge in both diagnosis and management. The disease is associated with significant maternal as well as perinatal adverse effects, hence, this article aims at improving the knowledge of the women's health carers with the up-to-date and evidence-based, whenever possible, recommendations while managing patients with ICP.

A multi-million image Serial Femtosecond Crystallography dataset collected at the European XFEL.

Serial femtosecond crystallography is a rapidly developing method for determining the structure of biomolecules for samples which have proven challenging with conventional X-ray crystallography, such as for membrane proteins and microcrystals, or for time-resolved studies. The European XFEL, the first high repetition rate hard X-ray free electron laser, provides the ability to record diffraction data at more than an order of magnitude faster than previously achievable, putting increased demand on sample delivery and data processing. This work describes a publicly available serial femtosecond crystallography dataset collected at the SPB/SFX instrument at the European XFEL. This dataset contains information suitable for algorithmic development for detector calibration, image classification and structure determination, as well as testing and training for future users of the European XFEL and other XFELs.

Pemphigoid Gestationis and adverse pregnancy outcomes: A literature review.

Pemphigoid gestationis (PG), also known as gestational pemphigoid, as it is specifically associated with a pregnancy event, is among the rare pregnancy-related dermatoses, characterised by the formation of autoantibodies against Bullous Pemphigoid antigens 180 and 230 (BP180 and BP230), causing significant damage to the basement membrane of the skin, resulting in marked pruritus and blisters on the abdomen and extremities. Diagnosis of PG is basically made by the characteristic clinical picture and confirmed by immunofluorescence studies and histopathology of a skin biopsy. Treatment, just as for other autoimmune dermatoses, is achieved by corticosteroids with the risk of relapses in subsequent pregnancies. Fetal growth restriction and pre-maturity are potential fetal complications associated with the disease, hence the recommended combined antenatal care by a dermatologist as well as an obstetrician, however, this disease is unlikely to be a source of significant maternal morbidity or mortality.

Vitiligo and pregnancy: How do each affect the other?

Vitiligo is one of the dermatomes affecting the melanocytes resulting in their destruction and subsequent patchy depigmentation of the skin. It is postulated to occur due to an autoimmune problem. Despite being a disease with limited systemic involvement and lack of mortality, it has a severe psychological impact. It may have a powerfully negative effect on a patient's quality of life. The relationship between vitiligo and pregnancy is not widely acknowledged. It may be associated with adverse pregnancy outcomes such as recurrent miscarriage, prematurity, intrauterine growth retardation and pre-eclampsia. Herein, this review describes the disease's adverse effects on pregnancy outcomes and the influence of pregnancy itself on the clinical evolution and prognosis of vitiligo.

Comparative Study of Intralesional Vitamin D3 Injection and Candida Albicans Antigen in Treating Plantar Warts.

BACKGROUND: Warts, or verrucae, are mucosal human papilloma virus (HPV) infections that are very challenging to treat. OBJECTIVE: To compare the safety and efficacy of intralesional injection of vitamin D3 versus intralesional injection of candida albicans antigen for plantar warts. METHODS: Forty patients were included in the study and were divided into two groups (A&B) with 20 patients each. Group A received intralesional vitamin D3 while Group B received intralesional Candida antigen. Injection was done every 3 weeks until clearance of warts or a maximum of three treatments. RESULTS: Nine patients showed complete clearance in group A (45%), while 6 patients (30%) showed partial response and no response in 5 patients (25%) of group (A). As for group (B), complete clearance of the treated warts was observed in 8 patients (40%), partial response in 6 patients (30%) while no response was observed in 6 patients (30%). No superiority of one treatment to the other was observed nor was any statistical significance in both groups’ responses noted. CONCLUSION: Treatment of multiple warts by intralesional injection of candida antigen or vitamin D3 is safe and effective, with good cure rates, has an excellent safety profile, with minimal recurrences and statistically equivalent. J Drugs Dermatol. 2021;20(5):546-549. doi:10.36849/JDD.5264.

The 1-Megapixel pnCCD detector for the Small Quantum Systems Instrument at the European XFEL: system and operation aspects.

The X-ray free-electron lasers that became available during the last decade, like the European XFEL (EuXFEL), place high demands on their instrumentation. Especially at low photon energies below 1 keV, detectors with high sensitivity, and consequently low noise and high quantum efficiency, are required to enable facility users to fully exploit the scientific potential of the photon source. A 1-Megapixel pnCCD detector with a 1024 × 1024 pixel format has been installed and commissioned for imaging applications at the Nano-Sized Quantum System (NQS) station of the Small Quantum System (SQS) instrument at EuXFEL. The instrument is currently operating in the energy range between 0.5 and 3 keV and the NQS station is designed for investigations of the interaction of intense FEL pulses with clusters, nano-particles and small bio-molecules, by combining photo-ion and photo-electron spectroscopy with coherent diffraction imaging techniques. The core of the imaging detector is a pn-type charge coupled device (pnCCD) with a pixel pitch of 75 µm × 75 µm. Depending on the experimental scenario, the pnCCD enables imaging of single photons thanks to its very low electronic noise of 3 e- and high quantum efficiency. Here an overview on the EuXFEL pnCCD detector and the results from the commissioning and first user operation at the SQS experiment in June 2019 are presented. The detailed descriptions of the detector design and capabilities, its implementation at EuXFEL both mechanically and from the controls side as well as important data correction steps aim to provide useful background for users planning and analyzing experiments at EuXFEL and may serve as a benchmark for comparing and planning future endstations at other FELs.

Pharmacological evaluation of prophylactic anti-microbial use in laparoscopic cholecystectomy; an open labelled study evaluating the concentrations of single dose intravenous ceftriaxone at serum and tissue level.

OBJECTIVE: The goal of administering preoperative systemic prophylactic antibiotics is to have the concentration in the tissues at its optimum level at the start and throughout the surgery. The rationale for the use of antibiotics is not well accepted; possible side effects and development of microbial resistance patterns are potential risks along with the financial burden. Therefore, the present study was conducted with the aim to clinically evaluate the serum and tissue concentration of single-dose prophylactic ceftriaxone during an ongoing laparoscopic cholecystectomy (LC) and to find out risk factors for post operative surgical site infections (SSI). METHOD: It was an open labelled prospective study in 50 consecutive patients who underwent elective laparoscopic cholecystectomy under prophylactic cover of ceftriaxone. Serum and tissue concentration were estimated by High Performance Liquid Chromatography during the ongoing surgery. Subjects were observed for any post-operative complications including SSI. RESULTS: Serum and tissue concentrations of ceftriaxone were significant at test value of 4 milligrams/Litre. Body mass index was significantly correlated with the tissue concentration of ceftriaxone at the time of incision. The rate of SSI was 2%. It significantly correlated with age more than 60 years, diabetes and infected bile. CONCLUSION: A single prophylactic intra-venous dose of 1 g ceftriaxone immediately prior to skin incision in LC is good enough for prevention of SSI in Indian patients.

Association Between Physician Industry Payments and Cost of Anterior Cervical Discectomy and Fusion in Medicare Beneficiaries.

BACKGROUND: Neurosurgical spine specialists receive considerable amounts of industry support that may impact the cost of care. The aim of this study was to evaluate the association between industry payments received by spine surgeons and the total hospital and operating room (OR) costs of an anterior cervical discectomy and fusion (ACDF) procedure among Medicare beneficiaries. METHODS: All ACDF cases were identified among the Medicare carrier files from January 1, 2013, to December 31, 2014, and matched to the Medicare inpatient baseline file. The total hospital and OR charges were obtained for these cases. Charges were converted to cost using year-specific cost-to-charge ratios. Surgeons were identified among the Open Payments database, which is used to quantify industry support. Analyses were performed to examine the association between industry payments received and ACDF costs. RESULTS: Matching resulting in the inclusion of 2209 ACDF claims from 2013-2014. In 2013 and 2014, the mean total cost for an ACDF was $21,798 and $21,008, respectively; mean OR cost was $5878 and $6064, respectively. Mann-Whitney U test demonstrated no significant differences in the mean total or OR cost for an ACDF based on quartile of general industry payment received (P = 0.21 and P = 0.54), and linear regression found no association between industry general payments, research support, or investments on the total hospital cost (P = 0.41, P = 0.13, and P = 0.25, respectively), or OR cost for an ACDF (P = 0.35, P = 0.24, and P = 0.40, respectively). CONCLUSIONS: This study suggests that spine surgeons performing ACDF surgeries may receive industry support without impacting the cost of care.

Catheter Ablation for Brugada Syndrome.

Brugada syndrome (BrS) is an arrhythmogenic disease associated with an increased risk of ventricular fibrillation (VF) and sudden cardiac death (SCD). To date, the standard therapy for the prevention of SCD in BrS is the use of an implantable cardioverter-defibrillator (ICD) especially in patients who have experienced a prior cardiac arrest or syncopal events secondary to VF. However, ICDs do not prevent the occurrence of VF but react to defibrillate the VF episode, thereby preventing SCD. Often patients with recurrent VF have to be maintained on antiarrhythmic drugs that are effective but have remarkable adverse effects. An alternative therapy for BrS with recurrent VF is catheter ablation which emerged as an effective therapy in eliminating VF-triggering premature ventricular complexes in limited case series; however, there has been a remarkable progress in effectiveness of catheter ablation since epicardial substrate ablation was first applied in 2011 and such approach is now widely applicable.

Mapping and Ablation of Fascicular Tachycardias (Reentrant and Nonreentrant).

Fascicular ventricular tachycardia (FVT) usually involves the left fascicular system; namely the left posterior fascicle, anterior fascicle, and rarely the upper septal fascicle. It may also involve the right Purkinje arborization. This tachycardia can be seen in normal heart or in the setting of structural heart diseases. Monomorphic FVT can be reentrant or nonreentrant and verapamil-sensitive left FVT is the second most common type of idiopathic ventricular tachycardia (VT) after right ventricular outflow tract VT. This article focuses on the practical approach for both reentrant and nonreentrant FVT, explaining the mechanism, electrocardiographic features, and electrophysiologic features of FVT.

Protocol for Urgent and Emergent Cases at a Large Academic Level 1 Trauma Center.

Background Level 1 trauma centers are capable of caring for every aspect of injury and contain 24-hour in-house coverage by general surgeons, with prompt availability of nearly all other disciplines upon request. Despite the wide variety of trauma, currently reported protocols often focus on a single surgical service and studies describing their implementation are lacking. The aim of the current study was to characterize all urgent and emergent cases at a large academic Level 1 trauma center, characterize the specialty and nature of emergent operative cases, and assess the efficacy of the institutional trauma protocol on timing of surgery. Methods For this retrospective review, all urgent and emergent cases treated at a single institution, during a 34-month period (January 1, 2015-October 31, 2017), were identified. All included cases were subject to the Institutional Guidelines for Operative Urgent/Emergent Cases. Demographic characteristics for non-elective surgical emergent cases were compiled by level of urgency and operating room (OR) waiting times were compared by year, department, and Level. Results A total of 11,206 urgent and emergent operative cases were included, among over 16 surgical departments. Level 2 cases represented the majority of urgent/emergent cases (33%-36%), followed by Level 3 (25%-26%), Level 1 (21%-22%), Level 4 (12%-16%), and Level 5 (2%-4%). Univariate analysis demonstrated that the proportion of urgent and emergent cases, by level of urgency, did not significantly differ between each year. Operating room waiting time decreased significantly over each year from 2015, 2016, and 2017: 193.40 ± 4.78, 177.20 ± 3.29, and 82.01 ± 2.98 minutes, respectively. Conclusions To the authors' knowledge, this is the first study to characterize all urgent and emergent cases at a large academic Level 1 trauma center, outline the specialty and nature of emergent operative cases, and assess the efficacy of the institutional trauma protocol on surgical waiting times over a 34-month period.

Efficacy of Endocardial Ablation of Drug-Resistant Ventricular Fibrillation in Brugada Syndrome: Long-Term Outcome.

Background Both endocardial trigger elimination and epicardial substrate modification are effective in treating ventricular fibrillation (VF) in Brugada syndrome. However, the primary approach and the characteristics of patients who respond to endocardial ablation remain unknown. Methods Among 123 symptomatic Brugada syndrome patients (VF, 63%; syncope, 37%), ablation was performed in 21 VF/electrical storm patients, the majority of whom were resistant to antiarrhythmic drugs. Results Careful endocardial mapping revealed that 81% of the patients had no specific findings, whereas 19% of the patients, who experienced the most frequent VF episodes with notching of the QRS in lead V1, had delayed low-voltage fractionated endocardial electrograms. Ablation of VF triggers followed by endocardial substrate modification was performed in the right ventricular outflow tract in 85% of the cases and in the right ventricle in 15%. VF triggers could not be completely eliminated in 1 patient and VF became noninducible in 14 (88%) patients among 16 patients who underwent VF induction with normalization of Brugada-type ECG in 3. During follow-up (56.14±36.95 months), VF recurrence was observed in 7 patients. Importantly, all patients who had nothing of QRS in lead V1 did not respond to endocardial ablation despite presence of VF-triggering ectopic beats during ablation. Conclusions With careful documentation of VF-triggering ectopic beats and detailed endocardial mapping, endocardial VF trigger elimination followed by endocardial substrate modification has an excellent long-term outcome, whereas presence of QRS notching in lead V1 was associated with high VF recurrence suggesting epicardial substrate ablation as effective initial approach.

Grand-potential-based phase-field model for multiple phases, grains, and chemical components.

Grand-potential-based phase-field model for multiple phases, grains, and chemical components is derived from a grand-potential functional. Due to the grand-potential formulation, the chemical energy does not contribute to the interfacial energy between phases, simplifying parametrization and decoupling interface thickness from interfacial energy, which can potentially allow increased interface thicknesses and therefore improved computational efficiency. Two-phase interfaces are stable with respect to the formation of additional phases, simplifying implementation and allowing the variational form of the evolution equations to be used. Additionally, we show that grand-potential-based phase-field models are capable of simulating phase separation, and we derive conditions under which this is possible.

Radiofrequency Catheter Ablation of Ventricular Tachycardia in Patients With Hypertrophic Cardiomyopathy and Apical Aneurysm.

OBJECTIVES: This study evaluated the characteristics and results of radiofrequency catheter ablation (RFCA) of ventricular tachycardia (VT) in patients with hypertrophic cardiomyopathy (HCM) and left ventricular apical aneurysm (AA). BACKGROUND: Monomorphic VT in patients with HCM and left ventricular AA has been reported. However, outcome data of RFCA are insufficient. METHODS: Fifteen patients with HCM and AA who underwent RFCA for VT at 5 different institutions were included in this study. The data were evaluated retrospectively. RESULTS: Endocardial voltage mapping showed a low-voltage area (LVA), and late potential in the AA was recorded in 12 patients (80%). Although epicardial or intramural origin of VT was suspected in 7 patients, endocardial RFCA successfully suppressed the VT at the LVA border (n = 10) or within the LVA (n = 2). In 2 of 3 patients without LVA at the endocardial site, linear RFCA at the anterior wall of the aneurysmal neck side was successful. In the remaining patient, endocardial RFCA of AA was not effective, and epicardial RFCA site was needed. In all patients, clinical VT became noninducible after RFCA. VT recurrence was observed in 2 patients (13.3%) during the 12-month follow-up period. One patient underwent a second endocardial RFCA, and no VT recurrence was noted. In the other patient, VT recurred 3 months after RFCA and was successfully terminated by antitachycardia pacing of the implantable cardioverter-defibrillator. CONCLUSIONS: In patients with HCM and AA, endocardial RFCA of AA effectively suppressed monomorphic VT which was related to AA and resulted in satisfactory outcomes.