Blog Archive

Αλέξανδρος Γ. Σφακιανάκης

Loading...

Sunday, December 18, 2022

Impact of SARS-CoV-2 variants on inpatient clinical outcome

alexandrossfakianakis shared this article with you from Inoreader
Abstract
Background
Prior observation has shown differences in COVID-19 hospitalization risk between SARS-CoV-2 variants, but limited information describes hospitalization outcomes.
Methods
Inpatients with COVID-19 at five hospitals in the eastern United States were included if they had hypoxia, tachypnea, tachycardia, or fever, and SARS-CoV-2 variant data, determined from whole genome sequencing or local surveillance inference. Analyses were stratified by history of SARS-CoV-2 vaccination or infection. The average effect of SARS-CoV-2 variant on 28-day risk of severe disease, defined by advanced respiratory support needs, or death was evaluated using models weighted on propensity scores derived from baseline clinical features.
Results
Severe disease or death within 28 days occurred for 977 (29%) of 3,369 unvaccinated patients and 269 (22%) of 1,230 patients with history of vaccination or prior SARS-CoV-2 infection. Among unvac cinated patients, the relative risk of severe disease or death for Delta variant compared to ancestral lineages was 1.30 (95% confidence interval [CI] 1.11-1.49). Compared to Delta, this risk for Omicron patients was 0.72 (95% CI 0.59-0.88) and compared to ancestral lineages was 0.94 (95% CI 0.78-1.1). Among Omicron and Delta infections, patients with history of vaccination or prior SARS-CoV-2 infection had half the risk of severe disease or death (adjusted hazard ratio 0.40, 95% CI 0.30-0.54), but no significant outcome difference by variant.
Conclusions
Although risk of severe disease or death for unvaccinated inpatients with Omicron was lower than Delta, it was similar to ancestral lineages. Severe outcomes were less common in vaccinated inpatients, with no difference between Delta and Omicron infections.
View on Web
Posted by at No comments:

Comparison of 4‐ or 6‐implant supported immediate full‐arch fixed prostheses: A retrospective cohort study of 217 patients followed up for 3–13 years

alexandrossfakianakis shared this article with you from Inoreader

Abstract

Purpose

Choosing four or six implants to support immediate full-arch fixed prostheses (FAFPs) is still controversial worldwide. This study aims to analyze and compare the long-term results of All-on-4 and All-on-6.

Materials and Methods

This retrospective cohort study enrolled 217 patients rehabilitated with 1222 implants supporting 271 FAFPs, including 202 prostheses supported by 4 implants (All-on-4 group) and 69 prostheses supported by 6 implants (All-on-6 group), and followed up for 3–13 years. Implant survival, prosthesis survival, complications, and implant marginal bone loss (MBL) were evaluated and compared between two groups. Patient characteristics including age, gender, jaw, opposite dentition condition, smoking habit, bruxism, bone quantity and quality, cantilever length (CL), prosthesis material, and oral hygiene were analyzed to assess their influence on the clinical results of the two groups. Six surgeons and three prosthodontists who performed FAFPs more than 5 years were invited for questionnaires, to assess patient- and clinician-related influences on implant number.

Result

In general, All-on-4 group indicated no significant difference with All-on-6 group in the implant survival (implant-level: hazard ratio [HR] = 1.0 [95% confidence interval (CI): 0.8–1.2], P = 0.96; prosthesis-level: HR = 0.8 [95% CI: 0.3–1.8], P = 0.54), prosthesis survival (odds ratio [OR] = 0.8 [95% CI: 0.3–2.8], P = 0.56), biological complications (OR = 0.9 [95% CI: 0.5–1.8], P = 0.78), technical complications of provisional prosthesis (OR = 1.3 [95% CI: 0.7–2.3], P = 0.42), technical complications of definitive prosthesis (OR = 1.1 [95% CI: 0.6–2.2], P = 0.33) and the 1st, 5th, and 10th year MBL (P = 0.65, P = 0.28, P = 0.14). However, for specific covariates, including elderly patients, opposing natural/fixed dentition, smoking, bruxism, long CL, low bone density, and all acrylic provisional prostheses, All-on-6 was more predictable in some clinical measurements than All-on-4. The implant prosthodontists and the medium-experienced clinicians showed significant preference for All-on-6 (P < 0.05).

Conclusion

Based on this study, the long-term clinical results showed no significant difference between All-on-4 and All-on-6 groups in general. However, for some specific characteristics, All-on-6 seemed to be more predictable in some clinical measurements than All-on-4. For the clinicians' decision-making, medium-experienced clinicians and the implant prosthodontists showed significant preference for All-on-6.
View on Web
Posted by at No comments:

Synthetic CT in Musculoskeletal Disorders: A Systematic Review

alexandrossfakianakis shared this article with you from Inoreader
imageRepeated computed tomography (CT) examinations increase patients' ionizing radiation exposure and health costs, making an alternative method desirable. Cortical and trabecular bone, however, have short T2 relaxation times, causing low signal intensity on conventional magnetic resonance (MR) sequences. Different techniques are available to create a "CT-like" contrast of bone, such as ultrashort echo time, zero echo time, gradient-echo, and susceptibility-weighted image MR sequences, and artificial intelligence. This systematic review summarizes the essential technical background and developmen ts of ultrashort echo time, zero echo time, gradient-echo, susceptibility-weighted image MR imaging sequences and artificial intelligence; presents studies on research and clinical applications of "CT-like" MR imaging; and describes their main advantages and limitations. We also discuss future opportunities in research, which patients would benefit the most, the most appropriate situations for using the technique, and the potential to replace CT in the clinical workflow.
View on Web
Posted by at No comments:

Synthetic Contrasts in Musculoskeletal MRI: A Review

alexandrossfakianakis shared this article with you from Inoreader
imageThis review summarizes the existing techniques and methods used to generate synthetic contrasts from magnetic resonance imaging data focusing on musculoskeletal magnetic resonance imaging. To that end, the different approaches were categorized into 3 different methodological groups: mathematical image transformation, physics-based, and data-driven approaches. Each group is characterized, followed by examples and a brief overview of their clinical validation, if present. Finally, we will discuss the advantages, disadvantages, and caveats of synthetic contrasts, focusing on the preservation of im age information, validation, and aspects of the clinical workflow.
View on Web
Posted by at No comments:

Quantitative MRI for Evaluation of Musculoskeletal Disease: Cartilage and Muscle Composition, Joint Inflammation, and Biomechanics in Osteoarthritis

alexandrossfakianakis shared this article with you from Inoreader
imageMagnetic resonance imaging (MRI) is a valuable tool for evaluating musculoskeletal disease as it offers a range of image contrasts that are sensitive to underlying tissue biochemical composition and microstructure. Although MRI has the ability to provide high-resolution, information-rich images suitable for musculoskeletal applications, most MRI utilization remains in qualitative evaluation. Quantitative MRI (qMRI) provides additional value beyond qualitative assessment via objective metrics that can support disease characterization, disease progression monitoring, or therapy response. In t his review, musculoskeletal qMRI techniques are summarized with a focus on techniques developed for osteoarthritis evaluation. Cartilage compositional MRI methods are described with a detailed discussion on relaxometric mapping (T2, T2*, T1ρ) without contrast agents. Methods to assess inflammation are described, including perfusion imaging, volume and signal changes, contrast-enhanced T1 mapping, and semiquantitative scoring systems. Quantitative characterization of structure and function by bone shape modeling and joint kinematics are described. Muscle evaluation by qMRI is discussed, including size (area, volume), relaxometric mapping (T1, T2, T1ρ), fat fraction quantification, diffusion imaging, and metabolic assessment by 31P-MR and creatine chemical exchange saturation transfer. Other notable technologies to support qMRI in musculoskeletal evaluation are described, including magnetic resonance fingerprinting, ultrashort echo time imaging, ultrahigh-field MRI, and hybrid MRI-p ositron emission tomography. Challenges for adopting and using qMRI in musculoskeletal evaluation are discussed, including the need for metal artifact suppression and qMRI standardization.
View on Web
Posted by at No comments:

Brachial Plexus Magnetic Resonance Neurography: Technical Challenges and Solutions

alexandrossfakianakis shared this article with you from Inoreader
imageMagnetic resonance neurography of the brachial plexus (BP) is challenging owing to its complex anatomy and technical obstacles around this anatomic region. Magnetic resonance techniques to improve image quality center around increasing nerve-to-background contrast ratio and mitigating imaging artifacts. General considerations include unilateral imaging of the BP at 3.0 T, appropriate selection and placement of surface coils, and optimization of pulse sequences. Technical considerations to improve nerve conspicuity include fat, vascular, and respiratory artifact suppression techniques; metal ar tifact reduction techniques; and 3-dimensional sequences. Specific optimization of these techniques for BP magnetic resonance neurography greatly improves image quality and diagnostic confidence to help guide nonoperative and operative management.
View on Web
Posted by at No comments:

Modern Low-Field MRI of the Musculoskeletal System: Practice Considerations, Opportunities, and Challenges

alexandrossfakianakis shared this article with you from Inoreader
imageMagnetic resonance imaging (MRI) provides essential information for diagnosing and treating musculoskeletal disorders. Although most musculoskeletal MRI examinations are performed at 1.5 and 3.0 T, modern low-field MRI systems offer new opportunities for affordable MRI worldwide. In 2021, a 0.55 T modern low-field, whole-body MRI system with an 80-cm-wide bore was introduced for clinical use in the United States and Europe. Compared with current higher-field-strength MRI systems, the 0.55 T MRI system has a lower total ownership cost, including purchase price, installation, and maintenance. Althou gh signal-to-noise ratios scale with field strength, modern signal transmission and receiver chains improve signal yield compared with older low-field magnetic resonance scanner generations. Advanced radiofrequency coils permit short echo spacing and overall compacter echo trains than previously possible. Deep learning–based advanced image reconstruction algorithms provide substantial improvements in perceived signal-to-noise ratios, contrast, and spatial resolution. Musculoskeletal tissue contrast evolutions behave differently at 0.55 T, which requires careful consideration when designing pulse sequences. Similar to other field strengths, parallel imaging and simultaneous multislice acquisition techniques are vital for efficient musculoskeletal MRI acquisitions. Pliable receiver coils with a more cost-effective design offer a path to more affordable surface coils and improve image quality. Whereas fat suppression is inherently more challenging at lower field strengths, chemical s hift selective fat suppression is reliable and homogeneous with modern low-field MRI technology. Dixon-based gradient echo pulse sequences provide efficient and reliable multicontrast options, including postcontrast MRI. Metal artifact reduction MRI benefits substantially from the lower field strength, including slice encoding for metal artifact correction for effective metal artifact reduction of high-susceptibility metallic implants. Wide-bore scanner designs offer exciting opportunities for interventional MRI. This review provides an overview of the economical aspects, signal and image quality considerations, technological components and coils, musculoskeletal tissue relaxation times, and image contrast of modern low-field MRI and discusses the mainstream and new applications, challenges, and opportunities of musculoskeletal MRI.
View on Web
Posted by at No comments:

Changes in endemic patterns of respiratory syncytial virus infection in pediatric patients under the pressure of nonpharmaceutical interventions for COVID‐19 in Beijing, China

alexandrossfakianakis shared this article with you from Inoreader

Abstract

Background

A series of nonpharmaceutical interventions (NPIs) was launched in Beijing, China, on January 24, 2020, to control coronavirus disease 2019.

Methods

To reveal the roles of NPIs on respiratory syncytial virus (RSV), respiratory specimens collected from children with acute respiratory tract infection during Jul 2017 and Dec 2021 in Beijing were screened by CEMP assay. Specimens positive for RSV were subjected to PCR and genotyped by G gene sequencing and phylogenetic analysis using iqtree v1.6.12. The paraFix mutations were analyzed with the R package sitePath. Clinical data were compared using SPSS 22.0 software.

Results

Before NPIs launched, each RSV endemic season started from Oct/Nov to Feb/Mar of the next year in Beijing. After that, the RSV positive rate abruptly dropped from 31.93% in Jan to 4.39% in Feb 2020; then, a dormant state with RSV positive rates ≤1% from Mar to Sep, a nearly dormant state in Oct (2.85%) and Nov (2.98%) and a delayed endemic season in 2020, and abnormal RSV positive rates remaining at approximately 10% in summer until Sep 2021 were detected. Finally, an endemic RSV season returned from Oct 2021. There was a game between subtypes A and B, and RSV-A replaced RSV-B in July 2021 to become the dominant subtype. Six RSV-A and 8 RSV-B paraFix (parallel and fixed) mutations were identified on G. The percentage of severe pneumonia patients decreased to 40.51% after NPIs launched.

Conclusions

NPIs launched in Beijing seriously interfered with the endemic season of RSV.

This article is protected by copyright. All rights reserved.
View on Web
Posted by at No comments:

Prevalence of post-COVID Condition 12 Weeks after Omicron Infection Compared to Negative Controls and Association with Vaccination Status

alexandrossfakianakis shared this article with you from Inoreader

cid_ogimage.png

ABSTRACT
Background
Post-COVID symptoms can persist several months after SARS-CoV-2 infection. Little is known, however, about the prevalence of post-COVID condition following infections from Omicron variants and how this varies according to vaccination status
Objective
This study evaluates the prevalence of symptoms and functional impairment 12 weeks after an infection by Omicron variants (BA.1 and BA.2) compared to negative controls tested during the same peri od.
Methods
Outpatient individuals tested positive or negative for COVID-19 infection between December 2021 and February 2022 at the Geneva University Hospitals were followed 12 weeks after their test date.
Results
Overall, 11.7% of Omicron cases had symptoms 12 weeks after the infection compared to 10.4% of individuals who tested negative during the same period (p < 0.001), and symptoms were much less common in vaccinated vs non-vaccinated individuals with Omicron infection (9.7% vs 18.1%, p < 0.001). There were no significant differences in functional impairment at 12 weeks between Omicron cases and negative controls even after adjusting for multiple potential confounders.
Conclusion
The differential prevalence of post-COVID symptoms and functional impairment attributed to Omicron BA.1 and BA.2 infection is low when compared to negative controls. Vaccination is associated with lower prevalence of post-COVID symptoms.
View on Web
Posted by at No comments:

Weight and metabolic changes after switching from tenofovir alafenamide (TAF)/emtricitabine (FTC)+dolutegravir (DTG), tenofovir disoproxil fumarate (TDF)/FTC+DTG and TDF/FTC/efavirenz (EFV) to TDF/lamivudine (3TC)/DTG

alexandrossfakianakis shared this article with you from Inoreader

cid_ogimage.png

Abstract
Participants randomised to first-line tenofovir alafenamide (TAF)/emtricitabine (FTC)+dolutegravir (DTG), tenofovir disoproxil fumarate (TDF)/FTC+DTG or TDF/FTC/efavirenz (EFV) for 192 weeks were then switched to TDF/lamivudine (3TC)/DTG for 52 weeks. Participants switching either TAF/FTC+DTG or TDF/FTC/EFV to TDF/3TC/DTG showed statistically significant reductions in weight, low density lipoprotein, triglycerides, glucose and glycated haemoglobin.
View on Web
Posted by at No comments:
Subscribe to: Posts (Atom)