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1.
Am J Epidemiol ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38957996

RESUMO

Non-benzodiazepine hypnotics ( "Z-drugs") are prescribed for insomnia, but might increase risk of motor vehicle crash (MVC) among older adults through prolonged drowsiness and delayed reaction times. We estimated the effect of initiating Z-drug treatment on the 12-week risk of MVC in a sequential target trial emulation. After linking New Jersey driver licensing and police-reported MVC data to Medicare claims, we emulated a new target trial each week (July 1, 2007 - October 7, 2017) in which Medicare fee-for-service beneficiaries were classified as Z-drug-treated or untreated at baseline and followed for an MVC. We used inverse probability of treatment and censoring weighted pooled logistic regression models to estimate risk ratios (RR) and risk differences with 95% bootstrap confidence limits (CLs). There were 257,554 person-trials, of which 103,371 were Z-drug-treated and 154,183 untreated, giving rise to 976 and 1,249 MVCs, respectively. The intention-to-treat RR was 1.06 (95%CLs 0.95, 1.16). For the per-protocol estimand, there were 800 MVCs and 1,241 MVCs among treated and untreated person-trials, respectively, suggesting a reduced MVC risk (RR 0.83 [95%CLs 0.74, 0.92]) with sustained Z-drug treatment. Z-drugs should be prescribed to older patients judiciously but not withheld entirely over concerns about MVC risk.

2.
J Alzheimers Dis ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38995783

RESUMO

Background: Older adults with heart failure are at elevated risk of Alzheimer's disease and related dementias (AD/ADRD). Research suggests that insomnia and depressive episodes contribute somewhat dissociable impacts on risk for AD/ADRD in this patient population, although the temporal ordering of effects is unknown. Objective: This study examined time to dementia diagnosis among patients with comorbid insomnia and/or depressive episodes in an epidemiological sample. Methods: Secondary data analyses were conducted using a cohort study of 203,819 Veterans with a primary admission diagnosis of heart failure in 129 VA Medical Centers. Results: Patients with diagnoses of both insomnia and depressive episodes had the shortest time to a dementia diagnosis at both 1-year (Hazard ratio = 1.43, 95% CI [1.36, 1.51]) and 3-year follow-up time points (Hazard ratio = 1.40, 95% CI [1.34, 1.47]) versus patients with one or neither comorbidity. Conclusions: Individuals with both comorbidities had the shortest time to dementia onset. Screening for these comorbidities may help to identify patients at elevated risk of dementia who could benefit from enhanced monitoring or early intervention strategies for more rapid detection and management of dementia symptoms.

3.
Angew Chem Int Ed Engl ; : e202404492, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38948941

RESUMO

While plastics like polyethylene terephthalate can already be degraded efficiently by the activity of hydrolases, other synthetic polymers like polyurethanes (PUs) and polyamides (PAs) largely resist biodegradation. In this study, we solved the first crystal structure of the metagenomic urethanase UMG-SP-1, identified highly flexible loop regions to comprise active site residues, and targeted a total of 20 potential hot spots by site-saturation mutagenesis. Engineering campaigns yielded variants with single mutations, exhibiting almost 3- and 8-fold improved activity against highly stable N-aryl urethane and amide bonds, respectively. Furthermore, we demonstrated the release of the corresponding monomers from a thermoplastic polyester-PU and a PA (nylon 6) by the activity of a single, metagenome-derived urethanase after short incubation times. Thereby, we expanded the hydrolysis profile of UMG-SP-1 beyond the reported low-molecular weight carbamates. Together, these findings promise advanced strategies for the bio-based degradation and recycling of plastic materials and waste, aiding efforts to establish a circular economy for synthetic polymers.

4.
J Am Med Dir Assoc ; 25(8): 105101, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38906176

RESUMO

OBJECTIVE: Wandering behavior in nursing home (NH) residents could increase risk of infection. The objective of this study was to assess the association of wandering behavior with SARS-CoV-2 infection in Veterans Affairs (VA) Community Living Center (CLC) residents. DESIGN: Retrospective cohort study. SETTING & PARTICIPANTS: Veterans residing in 133 VA CLCs. METHODS: We included residents with SARS-CoV-2 test from March 1, 2020 to December 31, 2020 from VA electronic medical records. We identified CLC residents with wandering on Minimum Data Set 3.0 assessments and compared them with residents without wandering. The outcome was SARS-CoV-2 infection, as tested for surveillance testing, in those with and without wandering. Generalized linear model with Poisson link adjusted for relevant covariates was used. RESULTS: Residents (n = 9995) were included in the analytic cohort mean, (SD) age 73.4 (10.7); 388 (3.9%) women. The mean (SD) activities of daily living score in the overall cohort was 13.6 (8.25). Wandering was noted in 379 (3.8%) (n = 379) of the cohort. The exposure groups differed in prior dementia (92.6% vs 62.1%, standardized mean difference [SMD] = 0.8) and psychoses (41.4% vs 28.1%, SMD = 0.3). Overall, 12.5% (n = 1248) tested positive for SARS-CoV-2 and more residents among the wandering group were SARS-CoV-2 positive as compared with those in the group without wandering (19% [n = 72] vs 12.2% [n = 1176], SMD = 0.19). Adjusting for covariates, residents with wandering had 34% higher relative risk for SARS-CoV-2 infection (adjusted relative risk, 1.34; 95% CI, 1.04-1.69). CONCLUSIONS AND IMPLICATIONS: CLC residents with wandering had a higher risk of SARS-CoV-2 infection. This may inform implementation of infection control and isolation policies as NHs attempt to balance ethical concepts of resident autonomy, proportionality, equity, and utilitarianism.

5.
Appl Microbiol Biotechnol ; 108(1): 392, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38910173

RESUMO

In the last decades, biocatalysis has offered new perspectives for the synthesis of (chiral) amines, which are essential building blocks for pharmaceuticals, fine and bulk chemicals. In this regard, amidases have been employed due to their broad substrate scope and their independence from expensive cofactors. To expand the repertoire of amidases, tools for their rapid identification and characterization are greatly demanded. In this work an ultra-high throughput growth selection assay based on the production of the folate precursor p-aminobenzoic acid (PABA) is introduced to identify amidase activity. PABA-derived amides structurally mimic the broad class of commonly used chromogenic substrates derived from p-nitroaniline. This suggests that the assay should be broadly applicable for the identification of amidases. Unlike conventional growth selection assays that rely on substrates as nitrogen or carbon source, our approach requires PABA in sub-nanomolar concentrations, making it exceptionally sensitive and ideal for engineering campaigns that aim at enhancing amidase activities from minimally active starting points, for example. The presented assay offers flexibility in the adjustment of sensitivity to suit project-specific needs using different expression systems and fine-tuning with the antimetabolite sulfathiazole. Application of this PABA-based assay facilitates the screening of millions of enzyme variants on a single agar plate within two days, without the need for laborious sample preparation or expensive instruments, with transformation efficiency being the only limiting factor. KEY POINTS: • Ultra-high throughput assay (tens of millions on one agar plate) for amidase screening • High sensitivity by coupling selection to folate instead of carbon or nitrogen source • Highly adjustable in terms of sensitivity and expression of the engineering target.


Assuntos
Ácido 4-Aminobenzoico , Amidoidrolases , Ensaios de Triagem em Larga Escala , Amidoidrolases/metabolismo , Amidoidrolases/genética , Ensaios de Triagem em Larga Escala/métodos , Ácido 4-Aminobenzoico/metabolismo , Ácido 4-Aminobenzoico/química , Especificidade por Substrato , Escherichia coli/genética , Escherichia coli/enzimologia , Escherichia coli/metabolismo
6.
J Am Med Dir Assoc ; 25(9): 105120, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38945171

RESUMO

OBJECTIVES: Examine physical function change and physical therapy (PT) use in short-stay and long-stay residents not infected by CoVID-19 within Veterans Affairs (VA) Community Living Centers (CLCs). DESIGN: Retrospective cohort study using Minimum Data Set (MDS) 3.0 assessments. SETTINGS AND PARTICIPANTS: 12,606 Veterans in 133 VA CLCs between September 2019 and September 2020. METHODS: Difference in physical function [MDS Activities of Daily Living Score (MDS-ADL)] and PT use (minutes in past 7 days) from admission to last assessment in a period were compared between the pre-CoVID-19 (September 2019 to February 2020) and early CoVID-19 (April 2020 to September 2020) period using mixed effects regression with multivariable adjustment. Assessments after a positive CoVID-19 test were excluded. Differences were examined in the sample and repeated after stratifying into short- and long-stay stratums. RESULTS: Veterans admitted during early CoVID-19 had more comorbidities, worse MDS-ADL scores, and were more often long-stay residents compared with those admitted during pre-CoVID-19. In comparison to pre-CoVID-19, Veterans in VA CLCs during early CoVID-19 experienced greater improvements in their MDS-ADL (-0.49 points, 95% CI -0.27, -0.71) and received similar minutes of therapy (2.6 minutes, 95% CI -0.8, 6.0). Stratification revealed short-stay residents had relative improvements in their function (-0.69 points, 95% CI -0.44, -0.94) and higher minutes of PT (5.1 minutes, 95% CI 0.9, 9.2) during early CoVID-19 whereas long-stay residents did not see differences in functional change (0.08 points, 95% CI -0.36, 0.51) or PT use (-0.6 minutes, 95% CI -6.1, 4.9). CONCLUSIONS AND IMPLICATIONS: During early CoVID-19, physical function improved while the amount of PT received was maintained compared with pre-CoVID-19 for Veterans in VA CLCs. Short-stay residents experienced greater improvements in physical function and increases in PT use. These findings may be partly due to selection bias relating to Veterans admitted to CLCs during early CoVID-19.

7.
Angew Chem Int Ed Engl ; 63(30): e202405152, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-38739413

RESUMO

Biocatalysis provides an attractive approach to facilitate synthetic reactions in aqueous media. Motivated by the discovery of promiscuous aminolysis activity of esterases, we exploited the esterase from Pyrobaculum calidifontis VA1 (PestE) for the synthesis of carbamates from different aliphatic, aromatic, and arylaliphatic amines and a set of carbonates such as dimethyl-, dibenzyl-, or diallyl carbonate. Thus, aniline and benzylamine derivatives, aliphatic and even secondary amines could be efficiently converted into the corresponding benzyloxycarbonyl (Cbz)- or allyloxycarbonyl (Alloc)-protected products in bulk water, with (isolated) yields of up to 99 %.


Assuntos
Aciltransferases , Carbamatos , Esterases , Água , Esterases/metabolismo , Esterases/química , Carbamatos/química , Carbamatos/metabolismo , Carbamatos/síntese química , Água/química , Aciltransferases/metabolismo , Aciltransferases/química , Biocatálise , Estrutura Molecular , Aminas/química , Aminas/metabolismo
8.
Skeletal Radiol ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607418

RESUMO

OBJECTIVE: To compare image quality and diagnostic performance of 3T and 7T magnetic resonance imaging (MRI) for direct depiction of finger flexor pulleys A2, A3 and A4 before and after artificial pulley rupture in an ex-vivo model using anatomic preparation as reference. MATERIALS AND METHODS: 30 fingers from 10 human cadavers were examined at 3T and 7T before and after being subjected to iatrogenic pulley rupture. MRI protocols were comparable in duration, both lasting less than 22 min. Two experienced radiologists evaluated the MRIs. Image quality was graded according to a 4-point Likert scale. Anatomic preparation was used as gold standard. RESULTS: In comparison, 7T versus 3T had a sensitivity and specificity for the detection of A2, A3 and A4 pulley lesions with 100% vs. 95%, respectively 98% vs. 100%. In the assessment of A3 pulley lesions sensitivity of 7T was superior to 3T MRI (100% vs. 83%), whereas specificity was lower (95% vs. 100%). Image quality assessed before and after iatrogenic rupture was comparable with 2.74 for 7T and 2.61 for 3T. Visualization of the A3 finger flexor pulley before rupture creation was significantly better for 7 T (p < 0.001). Interobserver variability showed substantial agreement at 3T (κ = 0.80) and almost perfect agreement at 7T (κ = 0.90). CONCLUSION: MRI at 3T allows a comparable diagnostic performance to 7T for direct visualization and characterization of finger flexor pulleys before and after rupture, with superiority of 7T MRI in the visualization of the normal A3 pulley.

9.
J Psychiatr Res ; 173: 58-63, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38489871

RESUMO

Medical comorbidity, particularly cardiovascular diseases, contributes to high rates of hospital admission and early mortality in people with schizophrenia. The 30 days following hospital discharge represents a critical period for mitigating adverse outcomes. This study examined the odds of successful community discharge among Veterans with schizophrenia compared to those with major affective disorders and those without serious mental illness (SMI) after a heart failure hospital admission. Data for Veterans hospitalized for heart failure were obtained from the Veterans Health Administration (VHA) and Centers for Medicare & Medicaid Services between 2011 and 2019. Psychiatric diagnoses and medical comorbidities were assessed in the year prior to hospitalization. Successful community discharge was defined as remaining in the community without hospital readmission, death, or hospice for 30 days after hospital discharge. Logistic regression analyses adjusting for relevant factors were used to examine whether individuals with a schizophrenia diagnosis showed lower odds of successful community discharge versus both comparison groups. Out of 309,750 total Veterans in the sample, 7377 (2.4%) had schizophrenia or schizoaffective disorder and 32,472 (10.5%) had major affective disorders (bipolar disorder or recurrent major depressive disorder). Results from adjusted logistic regression analyses demonstrated significantly lower odds of successful community discharge for Veterans with schizophrenia compared to the non-SMI (Odds Ratio [OR]: 0.63; 95% Confidence Interval [CI]: 0.60, 0.66) and major affective disorders (OR: 0.65, 95%; CI: 0.62, 0.69) groups. Intervention efforts should target the transition from hospital to home in the subgroup of Veterans with schizophrenia.


Assuntos
Transtorno Depressivo Maior , Insuficiência Cardíaca , Transtornos Mentais , Esquizofrenia , Veteranos , Idoso , Humanos , Estados Unidos/epidemiologia , Esquizofrenia/epidemiologia , Esquizofrenia/terapia , Alta do Paciente , Veteranos/psicologia , Transtorno Depressivo Maior/epidemiologia , Transtorno Depressivo Maior/terapia , Estudos Retrospectivos , Medicare , Transtornos Mentais/epidemiologia , Transtornos Mentais/terapia , Transtornos Mentais/psicologia , Hospitalização
11.
Diagnostics (Basel) ; 14(6)2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38535042

RESUMO

In patients with premature ventricular contractions (PVCs), non-invasive mapping could locate the PVCs' origin on a personalized 3-dimensional (3D) heart model and, thus, facilitate catheter ablation therapy planning. The aim of our report is to evaluate its accuracy compared to invasive mapping in terms of assessing the PVCs' early activation zone (EAZ). For this purpose, non-invasive electrocardiographic imaging (ECGI) was performed using the Amycard 01C system (EP Solutions SA, Switzerland) in three cases. In the first step, a multichannel ECG (up to 224 electrodes) was recorded, and the dominant PVCs were registered. Afterward, a cardiac computed tomography (in two cases) or magnetic resonance imaging (in one case) investigation was carried out acquiring non-contrast torso scans for 8-electrode strip visualization and contrast heart acquisition. For the reconstructed epi/endocardial meshes of the heart, non-invasive isochronal maps were generated for the selected multichannel ECG fragments. Then, the patients underwent an invasive electrophysiological study, and the PVCs' activation was evaluated by a 3D mapping system (EnSite NavX Precision, Abbott). Finally, using custom-written software, we performed 3D fusion of the non-invasive and invasive models and compared the resulting isochronal maps. A qualitative analysis in each case showed the same early localization of the dominant PVC on the endocardial surface when comparing the non-invasive and invasive isochronal maps. The distance from the EAZ to the mitral or tricuspid annulus was comparable in the invasive/non-invasive data (36/41 mm in case N1, 73/75 mm in case N2, 9/12 mm in case N3). The area of EAZ was also similar between the invasive/non-invasive maps (4.3/4.5 cm2 in case N1, 7.1/7.0 cm2 in case N2, 0.4/0.6 cm2 in case N3). The distances from the non-invasive to invasive earliest activation site were 4 mm in case N1, 7 mm in case N2, and 4 mm in case N3. Such results were appropriate to trust the clinical value of the preoperative data in these cases. In conclusion, the non-invasive identification of PVCs before an invasive electrophysiological study can guide clinical and interventional decisions, demonstrating appropriate accuracy in the estimation of focus origin.

12.
Eur Radiol Exp ; 8(1): 30, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38472603

RESUMO

BACKGROUND: This study evaluated a deep learning (DL) algorithm for detecting vessel steno-occlusions in patients with peripheral arterial disease (PAD). It utilised a private dataset, which was acquired and annotated by the authors through their institution and subsequently validated by two blinded readers. METHODS: A single-centre retrospective study analysed 105 magnetic resonance angiography (MRA) images using an EfficientNet B0 DL model. Initially, inter-reader variability was assessed using the complete dataset. For a subset of these images (29 from the left side and 35 from the right side) where digital subtraction angiography (DSA) data was available as the ground truth, the model's accuracy and the area under the curve at receiver operating characteristics analysis (ROC-AUC) were evaluated. RESULTS: A total of 105 patient examinations (mean age, 75 years ±12 [mean ± standard deviation], 61 men) were evaluated. Radiologist-DL model agreement had a quadratic weighted Cohen κ ≥ 0.72 (left side) and ≥ 0.66 (right side). Radiologist inter-reader agreement was ≥ 0.90 (left side) and ≥ 0.87 (right side). The DL model achieved a 0.897 accuracy and a 0.913 ROC-AUC (left side) and 0.743 and 0.830 (right side). Radiologists achieved 0.931 and 0.862 accuracies, with 0.930 and 0.861 ROC-AUCs (left side), and 0.800 and 0.799 accuracies, with 0.771 ROC-AUCs (right side). CONCLUSION: The DL model provided valid results in identifying arterial steno-occlusion in the superficial femoral and popliteal arteries on MRA among PAD patients. However, it did not reach the inter-reader agreement of two radiologists. RELEVANCE STATEMENT: The tested DL model is a promising tool for assisting in the detection of arterial steno-occlusion in patients with PAD, but further optimisation is necessary to provide radiologists with useful support in their daily routine diagnostics. KEY POINTS: • This study focused on the application of DL for arterial steno-occlusion detection in lower extremities on MRA. • A previously developed DL model was tested for accuracy and inter-reader agreement. • While the model showed promising results, it does not yet replace human expertise in detecting arterial steno-occlusion on MRA.


Assuntos
Arteriopatias Oclusivas , Doença Arterial Periférica , Masculino , Humanos , Idoso , Meios de Contraste , Angiografia por Ressonância Magnética/métodos , Sensibilidade e Especificidade , Inteligência Artificial , Estudos Retrospectivos , Arteriopatias Oclusivas/diagnóstico
13.
J Psychosom Res ; 178: 111604, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38309130

RESUMO

OBJECTIVE: Adults with serious mental illness (SMI) have high rates of cardiovascular disease, particularly heart failure, which contribute to premature mortality. The aims were to examine 90- and 365-day all-cause medical or surgical hospital readmission in Veterans with SMI discharged from a heart failure hospitalization. The exploratory aim was to evaluate 180-day post-discharge engagement in cardiac rehabilitation, an effective intervention for heart failure. METHODS: This study used administrative data from the Veterans Health Administration (VHA) and Centers for Medicare & Medicaid Services between 2011 and 2019. SMI status and medical comorbidity were assessed in the year prior to hospitalization. Cox proportional hazards models (competing risk of death) were used to evaluate the relationship between SMI status and outcomes. Models were adjusted for VHA hospital site, demographics, and medical characteristics. RESULTS: The sample comprised 189,767 Veterans of which 23,671 (12.5%) had SMI. Compared to those without SMI, Veterans with SMI had significantly higher readmission rates at 90 (16.1% vs. 13.9%) and 365 (42.6% vs. 37.1%) days. After adjustment, risk of readmission remained significant (90 days: HR: 1.07, 95% CI: 1.03, 1.11; 365 days: HR: 1.10, 95% CI: 1.07, 1.12). SMI status was not significantly associated with 180-day cardiac rehabilitation engagement (HR: 0.98, 95% CI: 0.91, 1.07). CONCLUSIONS: Veterans with SMI and heart failure have higher 90- and 365-day hospital readmission rates even after adjustment. There were no differences in cardiac rehabilitation engagement based on SMI status. Future work should consider a broader range of post-discharge interventions to understand contributors to readmission.


Assuntos
Insuficiência Cardíaca , Transtornos Mentais , Veteranos , Idoso , Adulto , Humanos , Estados Unidos/epidemiologia , Readmissão do Paciente , Assistência ao Convalescente , Alta do Paciente , Medicare , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/terapia , Transtornos Mentais/epidemiologia
14.
J Am Geriatr Soc ; 72(2): 444-455, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37905738

RESUMO

BACKGROUND: Medications are one of the most easily modifiable risk factors for motor vehicle crashes (MVCs) among older adults, yet limited information exists on how the use of potentially driver-impairing (PDI) medications changes following an MVC. Therefore, we examined the number and types of PDI medication classes dispensed before and after an MVC. METHODS: This observational study included Medicare fee-for-service beneficiaries aged ≥67 years who were involved in a police-reported MVC in New Jersey as a driver between 2008 and 2017. Analyses were conducted at the "person-crash" level because participants could be involved in more than one MVC. We examined the use of 36 PDI medication classes in the 120 days before and 120 days after MVC. We described the number and prevalence of PDI medication classes in the pre-MVC and post-MVC periods as well as the most common PDI medication classes started and stopped following the MVC. RESULTS: Among 124,954 person-crashes, the mean (SD) age was 76.0 (6.5) years, 51.3% were female, and 83.9% were non-Hispanic White. The median (Q1 , Q3 ) number of PDI medication classes was 2 (1, 4) in both the pre-MVC and post-MVC periods. Overall, 20.3% had a net increase, 15.9% had a net decrease, and 63.8% had no net change in the number of PDI medication classes after MVC. Opioids, antihistamines, and thiazide diuretics were the top PDI medication classes stopped following MVC, at incidences of 6.2%, 2.1%, and 1.7%, respectively. The top medication classes started were opioids (8.3%), skeletal muscle relaxants (2.2%), and benzodiazepines (2.1%). CONCLUSIONS: A majority of crash-involved older adults were exposed to multiple PDI medications before and after MVC. A greater proportion of person-crashes were associated with an increased rather than decreased number of PDI medications. The reasons why clinicians refrain from stopping PDI medications following an MVC remain to be elucidated.


Assuntos
Acidentes de Trânsito , Condução de Veículo , Humanos , Idoso , Feminino , Estados Unidos/epidemiologia , Masculino , Medicare , Fatores de Risco , Veículos Automotores , New Jersey
16.
Front Sports Act Living ; 5: 1248581, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37828999

RESUMO

Purpose: Sport climbing may lead to tissue adaptation including finger cartilage before apparent surface damage is detectable. The main aim was to assess finger cartilage composition with T2 mapping in young, active climbers and to compare the results to a non-climbers' collective. A secondary aim was to compare whether differences in cartilage T2 times are observed between older vs. younger volunteers. Methods and materials: 7 Tesla MRI of the fingers Dig.2-4 was performed using a multi-echo spin echo sequence. Manual segmentation of 3 ROIs at the metacarpal heads, 1 ROI at the base phalanx and 1 ROI at the proximal interphalangeal joint was performed. Included were 13 volunteers without history of trauma who are regularly performing climbing activities as a recreational sport (>20 h/month). These were age-matched with 10 control subjects not performing climbing activities. Results: Mean age was 32.4 years for the climbing group and 25.8 years for the controls. Mean T2 values for the 5 different ROIs were 42.2 ± 7.8 msec for climbers and 41.4 ± 6.8 msec for non-climbers. No significant differences were observed for T2 values between both groups. However, higher age had a significant impact on T2 values for all assessed ROIs (higher age 44.2 ± 9.5, younger age 32.9 ± 5.7, p = 0.001). Discussion: This study evaluated the cartilage composition of young, engaged climbers with a T2 mapping MRI technique with the purpose to depict early onset joint changes. No negative impact on cartilage composition due to the sport activity was found, whereas age-related effects on the cartilage seemed to be more prominent.

17.
Int J Oral Maxillofac Implants ; 38(5): 923-932, 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37847834

RESUMO

PURPOSE: To compare bone substitutes composed of glycated collagen with synthetic micro-sized (1 to 10 µm) hydroxyapatite (OB) vs non-cross-linked collagen matrix with large-particle (250 to 1,000 µm) bovine-derived hydroxyapatite (BOC). MATERIALS AND METHODS: The P1 to P4 premolars were bilaterally extracted from the mandibles of 19 Beagle dogs. After 21 days, osteotomies were created in each dog that received OB or BOC and were covered with a collagen membrane or were left untreated. The animals were randomly divided into three groups based on sacrifice time (4, 12, or 24 weeks). The right and left hemimandibles were trimmed to facilitate imaging and histology, and all tissues were placed in 10% neutral-buffered formalin. Microcomputed tomography (MicroCT 40 Scanner, Scanco) was used to analyze bone sections. Bone volume, residual material volume, and bone mineral density were determined for each treatment site (OB and BOC) based on a volume of interest that encompassed the original defect. Additionally, blinded histopathologic assessment (based on the ISO 10993-6 scoring system) and histomorphometry were performed on sections ground to < 100 µm thick and stained with Stevenel's blue. RESULTS: No clinical side effects were noted. No statistical differences were observed for OB vs BOC regarding the mineral volume percentage. Compared to OB, BOC had significantly higher mean mineralization densities at 12 weeks (P < .01), but this difference did not extend to 24 weeks. For residual grafting material, bone maturation, alveolar ridge restoration, and inflammatory response, OB showed a residual amount of bone graft and no statistical differences compared to BOC. CONCLUSION: Both OB and BOC represent valid treatment options for critically sized bone defects. Both bone fillers outperformed the sham-operated, ungrafted (empty) control, demonstrating statistically improved bone growth and ridge restoration.


Assuntos
Aumento do Rebordo Alveolar , Substitutos Ósseos , Cães , Animais , Bovinos , Durapatita/uso terapêutico , Osteogênese , Microtomografia por Raio-X , Regeneração Tecidual Guiada Periodontal/métodos , Regeneração Óssea/fisiologia , Substitutos Ósseos/uso terapêutico , Colágeno/uso terapêutico , Aumento do Rebordo Alveolar/métodos
18.
Int J Oral Maxillofac Implants ; 38(4): 801-810, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37669520

RESUMO

Purpose: To compare glycated multilayered membranes (OV) to a commercially available thin-layer membrane (OP) in a lateral ridge augmentation model in dogs. Materials and Methods: This was designed as a three-arm study, where one negative control (empty defect) was compared to two test arms: alveolar bone defects grafted with a mixture of 90% deproteinized bovine bone mineral and 10% porcine collagen, then covered with either a thick- (OV) or thin-layered (OP) membrane. Animals were randomly divided into three groups corresponding to the final sacrifice times of 4 weeks, 12 weeks, and 24 weeks. Sections underwent microCT, histology, histopathology, and histomorphometry. Results: No statistical differences were observed for OV compared to OP regarding the percentage of mineral volume and mean mineral density, amount of bone maturation, percentage of bone graft and membrane remaining in the grafted area, alveolar ridge width measurements, membrane mineralization, or ossification. Test groups presented significantly higher values compared to the empty control for all the endpoints. Conclusions: Within its limitations, this in vivo study highlighted that multilayered thick glycated membranes can serve as effective occlusive barriers for up to 6 months.


Assuntos
Aumento do Rebordo Alveolar , Substitutos Ósseos , Animais , Bovinos , Cães , Aumento do Rebordo Alveolar/métodos , Regeneração Óssea , Colágeno , Regeneração Tecidual Guiada Periodontal , Membranas Artificiais , Minerais , Osteogênese , Suínos , Distribuição Aleatória
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