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1.
Dent J (Basel) ; 12(4)2024 Apr 11.
Article in English | MEDLINE | ID: mdl-38668015

ABSTRACT

Orthodontic mini-implants are devices used for anchorage in various orthodontic treatments. We conducted a pilot study which aimed to observe preliminary trends regarding the impact of heat treatment on the elastic modulus of Ti6Al4V alloy and stainless steel 316L mini-implants. The initial phase involved testing the impact of heat treatment on the mechanical properties of Ti6Al4V alloy and stainless steel 316L mini-implants. MATERIAL AND METHODS: Ten self-drilling mini-implants sourced from two distinct manufacturers (Jeil Medical Corporation® and Leone®) with dimensions of 2.0 mm diameter and 10 mm length were tested. They were separated into two material groups: Ti6Al4V and 316L. Using the CETRUMT-2 microtribometer equipment, indentation testing was conducted employing a diamond-tipped Rockwell penetrator at a constant force of 4.5 N. RESULTS: Slight differences were observed in the elastic modulus of the Ti6Al4V alloy (103.99 GPa) and stainless steel 316L (203.20 GPa) compared to natural bone. The higher elastic moduli of these materials indicate that they are stiffer, which could potentially lead to stress-shielding phenomena and bone resorption. Heat treatment resulted in significant changes in mechanical properties, including elastic modulus reductions of approximately 26.14% for Ti6Al4V and 24.82% for 316L, impacting their performance in orthodontic applications. CONCLUSION: Understanding the effects of heat treatment on these alloys is crucial for optimizing their biomechanical compatibility and longevity in orthodontic treatment. To fully evaluate the effects of heat treatment on mini-implants and to refine their design and efficacy in clinical practice, further research is needed.

2.
Brain Commun ; 6(2): fcae071, 2024.
Article in English | MEDLINE | ID: mdl-38495305

ABSTRACT

Enlarged perivascular spaces have been previously reported in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy, but their significance and pathophysiology remains unclear. We investigated associations of white matter enlarged perivascular spaces with classical imaging measures, cognitive measures and plasma proteins to better understand what enlarged perivascular spaces represent in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy and whether radiographic measures of enlarged perivascular spaces would be of value in future therapeutic discovery studies for cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy. Twenty-four individuals with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy and 24 age- and sex-matched controls were included. Disease status was determined based on the presence of NOTCH3 mutation. Brain imaging measures of white matter hyperintensity, brain parenchymal fraction, white matter enlarged perivascular space volumes, clinical and cognitive measures as well as plasma proteomics were used in models. White matter enlarged perivascular space volumes were calculated via a novel, semiautomated pipeline, and levels of 7363 proteins were quantified in plasma using the SomaScan assay. The relationship of enlarged perivascular spaces with global burden of white matter hyperintensity, brain atrophy, functional status, neurocognitive measures and plasma proteins was modelled with linear regression models. Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy and control groups did not exhibit differences in mean enlarged perivascular space volumes. However, increased enlarged perivascular space volumes in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy were associated with increased white matter hyperintensity volume (ß = 0.57, P = 0.05), Clinical Dementia Rating Sum-of-Boxes score (ß = 0.49, P = 0.04) and marginally with decreased brain parenchymal fraction (ß = -0.03, P = 0.10). In interaction term models, the interaction term between cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy disease status and enlarged perivascular space volume was associated with increased white matter hyperintensity volume (ß = 0.57, P = 0.02), Clinical Dementia Rating Sum-of-Boxes score (ß = 0.52, P = 0.02), Mini-Mental State Examination score (ß = -1.49, P = 0.03) and marginally with decreased brain parenchymal fraction (ß = -0.03, P = 0.07). Proteins positively associated with enlarged perivascular space volumes were found to be related to leukocyte migration and inflammation, while negatively associated proteins were related to lipid metabolism. Two central hub proteins were identified in protein networks associated with enlarged perivascular space volumes: CXC motif chemokine ligand 8/interleukin-8 and C-C motif chemokine ligand 2/monocyte chemoattractant protein 1. The levels of CXC motif chemokine ligand 8/interleukin-8 were also associated with increased white matter hyperintensity volume (ß = 42.86, P = 0.03), and levels of C-C motif chemokine ligand 2/monocyte chemoattractant protein 1 were further associated with decreased brain parenchymal fraction (ß = -0.0007, P < 0.01) and Mini-Mental State Examination score (ß = -0.02, P < 0.01) and increased Trail Making Test B completion time (ß = 0.76, P < 0.01). No proteins were associated with all three studied imaging measures of pathology (brain parenchymal fraction, enlarged perivascular spaces, white matter hyperintensity). Based on associations uncovered between enlarged perivascular space volumes and cognitive functions, imaging and plasma proteins, we conclude that white matter enlarged perivascular space volumes may capture pathologies contributing to chronic brain dysfunction and degeneration in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy.

4.
Article in English | MEDLINE | ID: mdl-37209261

ABSTRACT

PURPOSE OF REVIEW: The risk of cardiovascular complications due to SARS-CoV-2 are significantly increased within the first 6 months of the infection. Patients with COVID-19 have an increased risk of death, and there is evidence that many may experience a wide range of post-acute cardiovascular complications. Our work aims to provide an update on current clinical aspects of diagnosis and treatment of cardiovascular manifestations during acute and long-term COVID-19. RECENT FINDINGS: SARS-CoV-2 has been shown to be associated with increased incidence of cardiovascular complications such as myocardial injury, heart failure, and dysrhythmias, as well as coagulation abnormalities not only during the acute phase but also beyond the first 30 days of the infection, associated with high mortality and poor outcomes. Cardiovascular complications during long-COVID-19 were found regardless of comorbidities such as age, hypertension, and diabetes; nevertheless, these populations remain at high risk for the worst outcomes during post-acute COVID-19. Emphasis should be given to the management of these patients. Treatment with low-dose oral propranolol, a beta blocker, for heart rate management may be considered, since it was found to significantly attenuate tachycardia and improve symptoms in postural tachycardia syndrome, while for patients on ACE inhibitors or angiotensin-receptor blockers (ARBs), under no circumstances should these medications be withdrawn. In addition, in patients at high risk after hospitalization due to COVID-19, thromboprophylaxis with rivaroxaban 10 mg/day for 35 days improved clinical outcomes compared with no extended thromboprophylaxis. In this work we provide a comprehensive review on acute and post-acute COVID-19 cardiovascular complications, symptomatology, and pathophysiology mechanisms. We also discuss therapeutic strategies for these patients during acute and long-term care and highlight populations at risk. Our findings suggest that older patients with risk factors such as hypertension, diabetes, and medical history of vascular disease have worse outcomes during acute SARS-CoV-2 infection and are more likely to develop cardiovascular complications during long-COVID-19.

5.
Curr Treat Options Neurol ; 25(4): 71-92, 2023.
Article in English | MEDLINE | ID: mdl-36950279

ABSTRACT

Purpose of review: The risks of cerebrovascular manifestations due to SARS-CoV-2 infection are significantly increased within the first 6 months of the infection. Our work aims to give an update on current clinical aspects of diagnosis and treatment of cerebrovascular manifestations during acute and long-term SARS-CoV-2 infection. Recent findings: The incidence of acute ischemic stroke and haemorrhagic stroke during acute SARS-CoV-2 patients is estimated at 0.9 to 4.6% and 0.5-0.9%, respectively, and were associated with increased mortality. The majority presented with hemiparesis, dysarthria, sensory deficits, and a NIHSS score within 5-15. In addition, beyond the first 30 days of infection people with COVID-19 exhibited increased risk of stroke. During acute phase, age, hypertension, diabetes, and medical history of vascular disease were increased in patients with COVID-19 with new onset of cerebrovascular manifestations, while during long-COVID-19, the risk of cerebrovascular manifestations were found increased regardless of these factors. The management of patients with large-vessel ischemic stroke fulfilling the intravenous thrombolysis criteria are successfully treated according to the guidelines, while hyperosmolar therapy is typically administered in 4- to 6-h intervals. In addition, prophylaxis of anticoagulation therapy is associated with a better prognosis and low mortality during acute and post hospital discharge of patients with COVID-19. Summary: In this work, we provide a comprehensive review of the current literature on acute and post-acute COVID-19 cerebrovascular sequelae, symptomatology, and its pathophysiology mechanisms. Moreover, we discuss therapeutic strategies for these patients during acute and long-term care and point populations at risk. Our findings suggest that older patients with risk factors such as hypertension, diabetes, and medical history of vascular disease are more likely to develop cerebrovascular complications.

6.
Angle Orthod ; 93(1): 104-110, 2023 01 01.
Article in English | MEDLINE | ID: mdl-36240427

ABSTRACT

OBJECTIVES: To evaluate and compare the efficiency of orthodontic treatment and surgical uprighting of first and second mandibular molars. MATERIALS AND METHODS: An electronic literature search in PubMed, Science Direct, Embase, Scopus, Web of Science, Cochrane Library, LILACS, and Google Scholar, as well as a hand search was conducted by two independent researchers to identify relevant articles up to January 2022. In addition, a manual search was done that included article reference lists, grey literature, and dissertations. The risk of bias of the included prospective and retrospective studies was assessed with the Risk Of Bias Tool In Non-randomized Studies of Interventions (ROBINS-I) assessment tool. RESULTS: A total of six nonrandomized clinical trials (non-RCT) evaluating the efficiency of mandibular molar orthodontic and/or surgical uprighting were included. The quality analysis showed certain defects of the Non-RCTs included and, according to the criteria used, the majority of the articles were judged to be of moderate quality. CONCLUSIONS: Based on the evidence, orthodontic and surgical uprighting appear to be effective treatment methods for mandibular molars. Surgical uprighting may be associated with more complications than orthodontic uprighting. However, the existing literature on the subject is limited, heterogeneous, and methodologically limited. Therefore, the outcomes should be interpreted carefully.


Subject(s)
Molar , Tooth Movement Techniques , Retrospective Studies , Prospective Studies , Tooth Movement Techniques/methods , Molar/surgery , Mandible/surgery
7.
Stem Cell Investig ; 9: 2, 2022.
Article in English | MEDLINE | ID: mdl-35280344

ABSTRACT

Alzheimer's disease (AD) is the most common type of dementia responsible for more than 121,499 deaths from AD in 2019 making AD the sixth-leading cause in the United States. AD is a progressive neurodegenerative disorder characterized by decline of memory, behavioral impairments that affects a person's ability to function independently ultimately leading to death. The current pressing need for a treatment for (AD) and advances in the field of cell therapy, has rendered stem cell therapeutics a promising field of research. Despite advancements in stem cell technology, confirmed by encouraging pre-clinical utilization of stem cells in AD animal models, the number of clinical trials evaluating the efficacy of stem cell therapy is limited, with the results of many ongoing clinical trials on cell therapy for AD still pending. Mesenchymal stem cells (MSCs) have been the main focus in these studies, reporting encouraging results concerning safety profile, however their efficacy remains unproven. In the current article we review the latest advances regarding different sources of stem cell therapy and present a comprehensive list of every available clinical trial in national and international registries. Finally, we discuss drawbacks arising from AD pathology and technical limitations that hinder the transition of stem cell technology from bench to bedside. Our findings emphasize the need to increase clinical trials towards uncovering the mode of action and the underlying therapeutic mechanisms of transplanted cells as well as the molecular mechanisms controlling regeneration and neuronal microenvironment.

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