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Contact Lens & Anterior Eye : the... Feb 2022With active investigation underway for embedded-circuit contact lenses, safe oxygen supply of these novel lenses remains a question. Central-to-peripheral corneal edema...
PURPOSE
With active investigation underway for embedded-circuit contact lenses, safe oxygen supply of these novel lenses remains a question. Central-to-peripheral corneal edema for healthy eyes during wear of soft contact (SCL) and scleral lenses (SL) with embedding components is assessed.
METHODS
Various 2-dimensional (2D) designs of SL and SCL with embedded components are constructed on Comsol Multiphysics 5.5. Local corneal swelling associated with the designed lenses is determined by a recently developed 2D metabolic-swelling model. Settled central post-lens tear-film thicknesses (PoLTFs) are set at 400 μm and 3 μm for SL and SCL designs, respectively. Each lens design has an axisymmetric central and an axisymmetric peripheral embedment. Oxygen permeability (Dk) of the lens and the embedments ranges from 0 to 200 Barrer. Dimensions and location of the embedments are varied to assess optimal-design configurations to minimize central-to-peripheral corneal edema.
RESULTS
By adjusting oxygen Dk of the central embedment, the peripheral embedment, or the lens matrix polymer, corneal swelling is reduced by up to 2.5 %, 1.5 %, or 1.4 % of the baseline corneal thickness, respectively, while keeping all other parameters constant. A decrease in PoLTF thickness from 400 μm to 3 μm decreases corneal edema by up to 1.8 % of the baseline corneal thickness. Shifting the peripheral embedment farther out towards the periphery and towards the anterior lens surface reduces peak edema by up to 1.3 % and 0.6 % of the baseline corneal thickness, respectively.
CONCLUSIONS
To minimize central-to-peripheral corneal edema, embedments should be placed anteriorly and far into the periphery to allow maximal limbal metabolic support and oxygen transport in the polar direction (i.e., the θ-direction in spherical coordinates). High-oxygen transmissibility for all components and thinner PoLTF thickness are recommended to minimize corneal edema. Depending on design specifications, less than 1 % swelling over the entire cornea is achievable even with oxygen-impermeable embedments.
Topics: Contact Lenses; Contact Lenses, Hydrophilic; Cornea; Corneal Edema; Edema; Humans; Oxygen; Sclera
PubMed: 33846087
DOI: 10.1016/j.clae.2021.101443 -
American Journal of Hematology Dec 2014A 21 year old male student presented in 1980 as an Olympic athlete with a 12 year history of jaundice, pallor, and darkened urine induced by the atraumatic exercise of...
A 21 year old male student presented in 1980 as an Olympic athlete with a 12 year history of jaundice, pallor, and darkened urine induced by the atraumatic exercise of swimming (1). Physical examination at that time was remarkable only for moderate scleral icterus without hepatosplenomegaly. Hematological examination revealed moderate macrocytosis (MCV 102 fL) without anemia (Hct 50%, Hb 17 g/dL, 9% reticulocytes). The peripheral blood smear showed occasional target cells. Red cell osmotic fragility was decreased. Red cell Na content was increased and K content was decreased, with reduced total monovalent ion content. Passive red cell permeability of both Na and K were increased. A supervised 2.5 hr swimming workout increased free plasma Hb from <5 to 45 mg/dL and decreased serum haptoglobin from 25 to 6 mg/dL. The post-exercise urine sediment was remarkable for hemosiderin-laden tubular epithelial cells, without frank hemoglobinuria. The circulating 15 day erythrocyte half-life measured after 6 days without exercise was further shortened to 12 days after resumption of twice-per-day swimming workouts for 1 week. The patient’s red cells were hypersensitive to shear stress applied by cone-plate viscometer.
Topics: Adolescent; Adult; Adult Children; Anemia, Hemolytic, Congenital; Erythrocytes; Glucuronosyltransferase; Hemochromatosis Protein; Hepatocytes; Heterozygote; Histocompatibility Antigens Class I; Humans; Hydrops Fetalis; Ion Channels; Liver; Male; Membrane Proteins; Middle Aged; Mutation; Osmotic Fragility; Pedigree
PubMed: 25044010
DOI: 10.1002/ajh.23799 -
Current Opinion in Rheumatology Jul 2017The Assessment of Spondyloarthritis International Society (ASAS) axial spondyloarthritis (axSpA) classification criteria marked a major step forward in SpA research,... (Review)
Review
PURPOSE OF REVIEW
The Assessment of Spondyloarthritis International Society (ASAS) axial spondyloarthritis (axSpA) classification criteria marked a major step forward in SpA research, distinguishing axial from peripheral disease, and allowing earlier identification through MRI. This facilitated all aspects of research including epidemiology, therapeutics and patient outcomes.
RECENT FINDINGS
The ASAS axSpA classification criteria have been applied broadly in research, and were validated in a recent meta-analysis of international studies. Concerns arose because of clinical differences between the clinical and imaging arms, which imply different risk for radiographic progression, and perform differently in validation studies. Low specificity of the MRI finding of sacroiliac joint bone marrow edema may lead to misclassification in populations with low axSpA prevalence. We suggest methodology to improve upon the criteria, including rigorous assessment of potential candidate criteria sets, discrete choice experiments to allow consideration of feature weights, and validation. Separately, assessment of structural and inflammatory MRI abnormalities should be performed to refine the MRI definition of sacroiliitis.
SUMMARY
The debate regarding the validation and modification of the ASAS axSpA classification criteria should lead to international efforts to build upon the gains made by these criteria, to further refine the axSpA population definitions for research and ultimately improve patient outcomes.
Topics: Bone Marrow; Disease Progression; Edema; Humans; Magnetic Resonance Imaging; Prevalence; Sacroiliac Joint; Sacroiliitis; Sensitivity and Specificity; Societies, Medical; Spondylarthritis; Spondylarthropathies; Spondylitis, Ankylosing
PubMed: 28376062
DOI: 10.1097/BOR.0000000000000402 -
Cureus Feb 2021T-cell prolymphocytic leukemia (T-PLL) is a very rare and aggressive lymphoproliferative disorder. We present a 70-year-old man with complaints of fatigue, low urinary...
T-cell prolymphocytic leukemia (T-PLL) is a very rare and aggressive lymphoproliferative disorder. We present a 70-year-old man with complaints of fatigue, low urinary output, and peripheral edema for one month. Objectively, he presented diminished respiratory sounds bilaterally and peripheral edema. Analytical study revealed mild anemia and mild lymphomonocytosis, acute kidney injury, and urinalysis with proteins, leukocytes, erythrocytes, and cylinders. Chest radiography was consistent with pleural effusion. Subsequent study showed new onset of thrombocytopenia with a progressive increase of lymphocytosis, in association with inguinal adenopathies and splenomegaly. Immunophenotypic study of peripheral blood and lymph node biopsy were compatible with the diagnosis of T-PLL. Negative serology for human T-cell lymphotropic virus type 1 (HTLV-1) excluded adult T-cell leukemia. Progressive changes in the peripheral blood smear were seen, finally showing the presence of lymphocytes with a cerebriform nucleus, revealing this variant. There was a rapid catastrophic progression, spontaneous tumor lysis syndrome, and death.
PubMed: 33732560
DOI: 10.7759/cureus.13299 -
Frontiers in Cardiovascular Medicine 2022From a pathogenetic point of view, heart failure (HF) is characterized by the activation of several neurohumoral pathways with a role in maintaining the cardiac output... (Review)
Review
From a pathogenetic point of view, heart failure (HF) is characterized by the activation of several neurohumoral pathways with a role in maintaining the cardiac output and the adequate perfusion pressure in target organs and tissues. Decreased cardiac output in HF with reduced ejection fraction causes activation of the sympathetic nervous system, the renin angiotensin aldosterone system, arginine-vasopressin system, natriuretic peptides, and endothelin, all of which cause water and salt retention in the body. As a result, patients will present clinically as the main symptoms: dyspnea and peripheral edema caused by fluid redistribution to the lungs and/or by fluid overload. By studying these pathophysiological mechanisms, biomarkers with a prognostic and therapeutic role in the management of edema were identified in patients with HF with low ejection fraction. This review aims to summarize the current data from the specialty literature of such biomarkers with a role in the pathogenesis of edema in HF with low ejection fraction. These biomarkers may be the basis for risk stratification and the development of new therapeutic means in the treatment of edema in these patients.
PubMed: 35783848
DOI: 10.3389/fcvm.2022.910100 -
Journal of Current Ophthalmology Jun 2016To present an overview on ultra-wide-field imaging in diabetic retinopathy. (Review)
Review
PURPOSE
To present an overview on ultra-wide-field imaging in diabetic retinopathy.
METHODS
A comprehensive search of the pubmed database was performed using the search terms of "ultra-wide-field imaging", "ultra-wide-field fluorescein angiography" and "diabetic retinopathy". The relevant original articles were reviewed.
RESULTS
New advances in ultra-wide-field imaging allow for precise measurements of the peripheral retinal lesions. A consistent finding amongst these articles was that ultra-wide-field imaging improved detection of peripheral lesion. There was discordance among the studies, however, on the correlation between peripheral diabetic lesions and diabetic macular edema.
CONCLUSIONS
Visualization of the peripheral retina using ultra-wide-field imaging improves diagnosis and classification of diabetic retinopathy. Additional studies are needed to better define the association of peripheral diabetic lesions with diabetic macular edema.
PubMed: 27331147
DOI: 10.1016/j.joco.2016.04.001 -
La Revue de Medecine Interne Feb 2023AA amyloidosis is secondary to the deposit of excess insoluble Serum Amyloid A (SAA) protein fibrils. AA amyloidosis complicates chronic inflammatory diseases,... (Review)
Review
AA amyloidosis is secondary to the deposit of excess insoluble Serum Amyloid A (SAA) protein fibrils. AA amyloidosis complicates chronic inflammatory diseases, especially chronic inflammatory rheumatisms such as rheumatoid arthritis and spondyloarthritis; chronic infections such as tuberculosis, bronchectasia, chronic inflammatory bowel diseases such as Crohn's disease; and auto-inflammatory diseases including familial Mediterranean fever. This work consists of the French guidelines for the diagnosis workup and treatment of AA amyloidosis. We estimate in France between 500 and 700 cases in the whole French population, affecting both men and women. The most frequent organ impaired is kidney which usually manifests by oedemas of the lower extremities, proteinuria, and/or renal failure. Patients are usually tired and can display digestive features anf thyroid goiter. The diagnosis of AA amyloidosis is based on detection of amyloid deposits on a biopsy using Congo Red staining with a characteristic green birefringence in polarized light. Immunohistochemical analysis with an antibody directed against Serum Amyloid A protein is essential to confirm the diagnosis of AA amyloidosis. Peripheral inflammatory biomarkers can be measured such as C Reactive protein and SAA. We propose an algorithm to guide the etiological diagnosis of AA amyloidosis. The treatement relies on the etiologic treatment of the undelying chronic inflammatory disease to decrease and/or normalize Serum Amyloid A protein concentration in order to stabilize amyloidosis. In case of renal failure, dialysis or even a kidney transplant can be porposed. Nowadays, there is currently no specific treatment for AA amyloidosis deposits which constitutes a therapeutic challenge for the future.
Topics: Male; Humans; Female; Serum Amyloid A Protein; Amyloidosis; Familial Mediterranean Fever; Chronic Disease; Renal Insufficiency
PubMed: 36759076
DOI: 10.1016/j.revmed.2022.12.004 -
Temperature (Austin, Tex.) 2014In this issue, Parrot and Young present the results of temperature measurements in young individuals "partying" with 3,4-methylenedioxymethamphetamine (MDMA or Ecstasy)....
In this issue, Parrot and Young present the results of temperature measurements in young individuals "partying" with 3,4-methylenedioxymethamphetamine (MDMA or Ecstasy). This editorial commentary briefly summarizes the main findings of their study, provides background gained from previous animal experiments, and reviews the implications for the development of future pharmacotherapies and harm reduction strategies.
PubMed: 27627800
DOI: 10.4161/23328940.2014.980137 -
Cureus Jun 2023The underpinning of Chronic Venous Insufficiency (CVI) is valvular dysfunction, which manifests on a spectrum depending on the severity of insufficiency and duration of... (Review)
Review
The underpinning of Chronic Venous Insufficiency (CVI) is valvular dysfunction, which manifests on a spectrum depending on the severity of insufficiency and duration of the disease. The mainstay of treatment relies on compression therapy of a proper type and intensity. In older adults, special consideration must be taken during the patient encounter to account for age-related factors. This review discusses the clinical presentation, diagnosis, and mimicking of CVI, focusing mainly on older adults. The epidemiology, risk factors, disease burden, and grave complications -- such as thrombosis and ulceration, are reviewed. The physiological impacts of CVI are described, providing the background for treatment strategies, including non-invasive, medical, and surgical therapies. The findings show advanced age to be an important risk factor contributing to CVI and that other age-related factors add to the risk of severe complications. Clinical assessments combined with objective measurements that assess localized skin water using tissue dielectric constant values or whole limb assessments may aid in the differential diagnosis. Furthermore, understanding the mechanism of action of compression therapy, the mainstay of CVI treatment, and its physiological impacts, allows for its informed use in geriatric patients with increased risks of potential compression-related side effects.
PubMed: 37485203
DOI: 10.7759/cureus.40687 -
Biomedicine & Pharmacotherapy =... May 2022Gabapentinoids are ligands of the α2-δ subunit of voltage-gated calcium channels (Cav) that have been associated with a risk of peripheral edema and acute heart...
INTRODUCTION
Gabapentinoids are ligands of the α2-δ subunit of voltage-gated calcium channels (Cav) that have been associated with a risk of peripheral edema and acute heart failure in connection with a potentially dual mechanism, vascular and cardiac.
OBJECTIVES & METHODS
All cases of peripheral edema or heart failure involving gabapentin or pregabalin reported to the French Pharmacovigilance Centers between January 1, 1994 and April 30, 2020 were included to describe their onset patterns (e.g., time to onset). Based on these data, we investigated the impact of gabapentinoids on the myogenic tone of rat third-order mesenteric arteries and on the electrophysiological properties of rat ventricular cardiomyocytes.
RESULTS
A total of 58 reports were included (gabapentin n = 5, pregabalin n = 53). The female-to-male ratio was 4:1 and the median age was 77 years (IQR 57-85, range 32-95). The median time to onset were 23 days (IQR 10-54) and 17 days (IQR 3-30) for non-cardiogenic edema and acute heart failure, respectively. Cardiogenic and non-cardiogenic peripheral edema occurred frequently after a dose escalation (27/45, 60%), and the course was rapidly favorable after discontinuation of gabapentinoid (median 7 days, IQR 5-13). On rat mesenteric arteries, gabapentinoids significantly decreased the myogenic tone to the same extent as verapamil and nifedipine. Acute application of gabapentinoids had no significant effect on Ca1.2 currents of ventricular cardiomyocytes.
CONCLUSION
Gabapentinoids can cause concentration-dependent peripheral edema of early onset. The primary mechanism of non-cardiogenic peripheral edema is vasodilatory edema secondary to altered myogenic tone, independent of Ca1.2 blockade under the experimental conditions tested.
Topics: Aged; Aged, 80 and over; Animal Experimentation; Animals; Edema; Female; Gabapentin; Heart Failure; Humans; Male; Middle Aged; Pharmacovigilance; Pregabalin; Rats
PubMed: 35303569
DOI: 10.1016/j.biopha.2022.112807