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1.
Int J Biol Macromol ; 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35026220

RESUMO

In this study, the effect of marjoram essential oil (MEO) on the mechanical, barrier, antioxidant and antimicrobial properties of mung bean protein isolate (MPI)/pullulan (PU) composite films and its influence on the quality of minced beef meat during 14 days storage at 4 °C was studied. The Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM) results confirmed the compatibility between components. Also, depend on the different ratios of combination of MEO and MPI/PU, tensile strength (TS) and elongation at break (EAB) were varied. The results showed that an increase in the level of the MPI led to a significant increment in TS and water-proof properties of the composite films. Also, with addition of MEO, the EAB of the antimicrobial blend-films was decreased, while TS and water-proof properties were increased. In addition, enrichment of the films with MEO led to a considerable positive effect on DPPH radical scavenging and antibacterial activity against pathogenic bacteria (Staphylococcus aureus and Escherichia coli). Based on the bacterial and chemical analyses of the minced meat samples, MEO-incorporation in MPI/PU films enhanced oxidative stability of minced beef samples, and also showed effective antimicrobial activity against all of the tested bacteria.

2.
World J Surg ; 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35006329

RESUMO

BACKGROUND: The negative effects of bullying, discrimination, harassment, and sexual harassment (BDHS) on well-being and productivity of surgical residents in training have been well documented. Despite this, little has changed over the past decade and these behaviors continue. The purpose of this study was to determine the prevalence of each abusive behavior experienced by residents, identify the perpetrators, and examine the reporting tendency. METHODS: A systematic review of articles published between 2010 and 2020 in the MEDLINE, EMBASE, and Cochrane databases was performed following PRISMA guidelines. The following search terms were used: bullying, harassment, sexual harassment, discrimination, abuse, residency, surgery, orthopedic surgery, general surgery, otolaryngology, obstetrics, gynecology, urology, plastic surgery, and training. RESULTS: Twenty-five studies with 29,980 surgical residents were included. Sixty-three percent, 43, 29, and 27% of surgical residents experienced BDHS, respectively. Female residents reported experiencing all BDHS behaviors more often. Thirty-seven percent of resident respondents reported burnout, and 33% reported anxiety/depression. Attending surgeons, followed by senior co-residents, were the most common perpetrators. Seventy-one percent did not report the behavior to their institution. Fifty-one percent stated this was due to fear of retaliation. Of those who reported their experiences, 56% stated they had a negative experience reporting. CONCLUSION: Our review demonstrates high prevalence rates of BDHS experienced by residents during surgical training, which have been associated with burnout, anxiety, and depression. The majority of residents did not report BDHS due to fear of retaliation. Residency programs need to devise methods to have a platform for residents to safely voice their complaints.

3.
Foot Ankle Int ; : 10711007211049169, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34983250

RESUMO

BACKGROUND: An international consensus group of experts was convened to collaboratively advance toward consensus opinions based on the best available evidence on key topics within cartilage repair of the ankle. The purpose of this article is to present the consensus statements on osteochondral lesions of the tibial plafond (OLTP) and on ankle instability with ankle cartilage lesions developed at the 2019 International Consensus Meeting on Cartilage Repair of the Ankle. METHODS: Forty-three experts in cartilage repair of the ankle were convened and participated in a process based on the Delphi method of achieving consensus. Questions and statements were drafted within 4 working groups focusing on specific topics within cartilage repair of the ankle, after which a comprehensive literature review was performed and the available evidence for each statement was graded. Discussion and debate occurred in cases where statements were not agreed on in unanimous fashion within the working groups. A final vote was then held. RESULTS: A total of 11 statements on OLTP reached consensus. Four achieved unanimous support and 7 reached strong consensus (greater than 75% agreement). A total of 8 statements on ankle instability with ankle cartilage lesions reached consensus during the 2019 International Consensus Meeting on Cartilage Repair of the Ankle. One achieved unanimous support, and seven reached strong consensus (greater than 75% agreement). CONCLUSIONS: These consensus statements may assist clinicians in the management of these difficult clinical pathologies. LEVEL OF EVIDENCE: Level V, mechanism-based reasoning.

4.
Carbohydr Polym ; 277: 118824, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34893241

RESUMO

Polysaccharides are macromolecules with important inherent properties and potential biotechnological applications. These complex carbohydrates exist throughout nature, especially in plants, from which they can be obtained with high yields. Different extraction and purification methods may affect the structure of polysaccharides and, due to the close relationship between structure and function, modify their biological activities. One of the possible applications of these polysaccharides is acting on the skin, which is the largest organ in the human body and can be aged by intrinsic and extrinsic processes. Skincare has been gaining worldwide attention not only to prevent diseases but also to promote rejuvenation in aesthetic treatments. In this review, we discussed the polysaccharides obtained from plants and their innovative potential for skin applications, for example as wound-healing, antimicrobial, antioxidant and anti-inflammatory, antitumoral, and anti-aging compounds.

5.
Popul Health Manag ; 2021 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-34851742

RESUMO

Type 2 diabetes mellitus (T2DM) affects 31.5 million adults in the United States and is commonly treated in primary care settings. One promising approach to comprehensive care is to focus on an all-or-none diabetes bundle measure, which ensures each patient meets a set of guideline-recommended measures. This requires a practice-level coordinated strategy. The purpose of this initiative was to help health care organizations (HCOs) improve the care and outcomes of patients with T2DM using an all-or-none bundle measure. This observational study was carried out in the context of a national best practices learning Collaborative that implemented targeted interventions in primary care settings and measured success using an all-or-none bundle measure. Ten AMGA member-HCOs, across 8 states, treating nearly 300,000 adult patients with T2DM in primary care participated. The primary measure, the Together 2 Goal® Core Bundle, included hemoglobin A1c (A1c) control (<8%), blood pressure (BP) control (<140/90 mmHg), lipid management (prescribed a statin), and medical attention for nephropathy. All 10 HCOs improved the Core Bundle measure during the 12-month Collaborative. The rate for the Core Bundle improved from 40.2% to 42.8%, an absolute increase of 2.6% (P < 0.001). In addition, 9 HCOs improved BP control, 8 improved lipid management, 6 improved attention to nephropathy, and 4 improved A1c control. Implementing interventions in primary care settings was successful in achieving comprehensive care for an estimated additional 7700 people living with T2DM who met all 4 components of the bundle measure during the 12-month intervention period.

6.
J Am Podiatr Med Assoc ; : 1-29, 2021 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-34951866

RESUMO

Historically recalcitrant to treatment, infection of the nail unit is a pervasive clinical condition affecting about 10%-20% of the U.S. population; patients present with both cosmetic symptomatology and pain, with subsequent dystrophic morphology. To date, the presumptive infectious etiologies include classically-reported fungal dermatophytes, non-dermatophyte molds, and yeasts. Until now, the prevalence and potential contribution of bacteria to the clinical course of dystrophic nails had been relatively overlooked, if not dismissed. Previously, diagnosis had been largely made via clinical presentation, although microscopic examinations (KOH) of nail scrapings to identify fungal agents, and more recently, panel-specific PCR assays have been employed to elucidate causative infectious agents. Each of these tools suffers from test-specific limitations. However, molecular-age medicine now includes DNA-based tools to universally assess any microbe or pathogen with a known DNA sequence. This affords clinicians with rapid DNA sequencing technologies at their disposal. These sequencing-based diagnostic tools confer the accuracy of DNA level certainty, while concurrently obviating cultivation or microbial phenotypical biases. Using DNA sequencing-based diagnostics, the results herein document the first identification and quantification of significant bacterial, rather than mycotic, pathogens to the clinical manifestation of dystrophic nails. In direct opposition to the prevailing and presumptive mycotic-based etiologies, the results herein invoke questions about the very basis for our current standards of care, including effective treatment regimens.

7.
Semin Nucl Med ; 2021 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-34911637

RESUMO

Neuroendocrine tumors (NETs) are uncommon malignancies of increasing incidence and prevalence. As these slow growing tumors usually overexpress somatostatin receptors (SSTRs), the use of 68Ga-DOTA-peptides (gallium-68 chelated with dodecane tetra-acetic acid to somatostatin), which bind to the SSTRs, allows for PET based imaging and selection of patients for peptide receptor radionuclide therapy (PRRT). PRRT with radiolabeled somatostatin analogues such as 177Lu-DOTATATE (lutetium-177-[DOTA,Tyr3]-octreotate), is mainly used for the treatment of metastatic or inoperable NETs. However, PRRT is generally administered at a fixed injected activity in order not to exceed dose limits in critical organs, which is suboptimal given the variability in radiopharmaceutical uptake among patients. Advances in SPECT (single photon emission computed tomography) imaging enable the absolute quantitative measure of the true radiopharmaceutical distribution providing for PRRT dosimetry in each patient. Personalized PRRT based on patient-specific dosimetry could improve therapeutic efficacy by optimizing effective tumor absorbed dose while limiting treatment related radiotoxicity.

8.
Bull Hosp Jt Dis (2013) ; 79(4): 226-229, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34842515

RESUMO

Paul W. Lapidus' work has formed the foundation of modern foot and ankle surgery. Variations of his popularizedtechnique, the Lapidus procedure, remain in regular usetoday for the management and correction of hallux valgus.We revisit Dr. Lapidus' career and accomplishments withan emphasis on his importance to the expanding divisionof foot and ankle surgery at the Hospital for Joint Diseases.

9.
J Foot Ankle Surg ; 2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34844856

RESUMO

Concentrated bone marrow aspirate (CBMA) offers an alternative to sesamoid resection in end stage sesamoid pathology. CBMA potentiates the anti-inflammatory effect, stimulates local tissue regeneration and osteogenesis, when injected into bone. The purpose of this study is to evaluate the functional outcomes in a cohort of athletes following CBMA injection for the treatment of hallux sesamoid disorders. A retrospective case series of consecutive patients treated with CBMA injection for hallux sesamoid disorders were identified. Radiographs, Foot and Ankle Outcome Scores (FAOS), and Visual Analogue Scale (VAS) score were collected pre- and postinjections. Descriptive statistics were presented as the mean and standard deviation for continuous variables and frequency as percentages for categorical variables. Fifteen consecutive patients with were included with a mean follow-up time of 20.1 (range 12-34) months. Significant improvement in all scoring subscales of the FAOS and VAS score was noted preinjection compared to final follow-up postinjection (p < .001). Eight of 11 patients that were involved in sports prior to the CBMA injection returned to play, with 7 successfully returning to preinjury level status. Three patients required further treatment (20%). The case series suggests that CBMA injection is a safe and effective treatment option for hallux sesamoid disorders with a high rate of return to play.

10.
Am J Sports Med ; : 3635465211057117, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34786970

RESUMO

BACKGROUND: Autologous osteochondral transplantation (AOT) using a cylindrical graft in the treatment of osteochondral lesions of the talus (OLTs) is typically indicated for patients with larger lesions. However, with lesions that are irregular in shape, the AOT graft may not completely replace the lesion. For these lesions, we utilize extracellular matrix cartilage allograft (EMCA) augmentation in AOT to act as a physiologic grout at the host-graft interface. PURPOSE: To determine if the combination of EMCA with concentrated bone marrow aspirate (CBMA) would improve integration of the host-graft interface and subsequently reduce postoperative cyst formation after AOT. It was also hypothesized that EMCA in conjunction with CBMA would demonstrate improved MOCART (magnetic resonance observation of cartilage repair tissue) scores and functional outcome scores at a minimum 2 years after surgery. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A retrospective analysis was performed comparing patients treated with AOT/CBMA alone and AOT with CBMA/EMCA. Clinical outcomes were evaluated with the Foot and Ankle Outcome Score. Magnetic resonance imaging appearance was evaluated with the use of the MOCART (magnetic resonance observation of cartilage repair tissue) score. Cyst formation was also evaluated on postoperative magnetic resonance imaging. RESULTS: A total of 26 patients were included in the AOT + CBMA/EMCA group (10 male, 16 female), and 34 patients were included in the AOT/CBMA group (17 male, 17 female). The mean Foot and Ankle Outcome Score significantly improved in both groups (P < .001) across all subscales (symptoms, pain, activities of daily living, sports activities, and quality of life), but there was no significant difference between groups at final follow-up. There was no significant difference in mean MOCART scores between the groups (P = .118). In the AOT/CBMA group, 3 patients (8.8%) complained of knee pain, and 1 (2.9%) required additional surgery (hardware removal). In the AOT + CBMA/EMCA group, 2 patients (7.7%) complained of knee pain, and 6 patients (23%) required additional surgery (3 hardware removals and 3 arthroscopic debridements of scar tissue in the ankle). CONCLUSION: We found that while EMCA with CBMA has benefit in regeneration and repair of OLT treated with bone marrow stimulation, there appears to be little benefit of EMCA over CBMA alone as a physiologic grout at the graft-host interface in OLT treated with AOT.

11.
Artigo em Inglês | MEDLINE | ID: mdl-34821989

RESUMO

Biocatalytic conversion of greenhouse gases such as carbon dioxide into commercial products is one of the promising key approaches to solve the problem of climate change. Microbial enzymes, including carbonic anhydrase, NAD-dependent formate dehydrogenase, ribulose bisphosphate carboxylase, and methane monooxygenase, have been exploited to convert atmospheric gases into industrial products. Carbonic anhydrases are Zn2+-dependent metalloenzymes that catalyze the reversible conversion of CO2 into bicarbonate. They are widespread in bacteria, algae, plants, and higher organisms. In higher organisms, they regulate the physiological pH and contribute to CO2 transport in the blood. In plants, algae, and photosynthetic bacteria carbonic anhydrases are involved in photosynthesis. Converting CO2 into bicarbonate by carbonic anhydrases can solidify gaseous CO2, thereby reducing global warming due to the burning of fossil fuels. This review discusses the three-dimensional structures of carbonic anhydrases, their physiological role in marine life, their catalytic mechanism, the types of inhibitors, and their medicine and industry applications.

12.
World J Orthop ; 12(10): 791-801, 2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34754835

RESUMO

BACKGROUND: There appears to be a close relationship between deformities at the knee joint and at the hindfoot in patients with knee osteoarthritis (OA). Despite this intrinsic link, there is a dearth of studies investigating alterations in hindfoot alignment following total knee arthroplasty (TKA) in patients with knee OA. AIM: To evaluate changes in alignment of the hindfoot following TKA, foot and ankle clinical outcomes in terms of subjective clinical scoring tools following surgical intervention, and to analyse the level of evidence (LOE) and quality of evidence (QOE) of the included studies. METHODS: MEDLINE, EMBASE and Cochrane Library databases were systematically reviewed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Studies reporting changes in the postoperative alignment of the hindfoot following TKA were included. The level and QOE were recorded and assessed. RESULTS: Eleven studies with a total of 1142 patients (1358 knees) met the inclusion/ exclusion criteria. Six studies were of LOE II and 5 studies were of LOE III. Patients with preoperative varus knee deformity and valgus hindfoot deformity demonstrated improvement in hindfoot alignment post TKA. Patients with preoperative varus knee deformity and varus hindfoot deformity demonstrated no improvement in hindfoot alignment following TKA. Twelve different radiographic parameters were used to measure the alignment of the hindfoot across the included studies, with the tibio-calcaneal angle most frequently utilised (27.3%). CONCLUSION: This systematic review demonstrated that the hindfoot may display compensatory changes in alignment following TKA in patients with knee OA. However, the marked heterogeneity between the included studies and poor QOE limits any meaningful cross sectional comparisons between studies. Further, well designed studies are necessary to determine the changes and outcomes of hindfoot alignment following TKA.

13.
Sci Rep ; 11(1): 22741, 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34815449

RESUMO

Models of bone remodelling could be useful in drug discovery, particularly if the model is one that replicates bone regeneration with reduction in osteoclast activity. Here we use nanovibrational stimulation to achieve this in a 3D co-culture of primary human osteoprogenitor and osteoclast progenitor cells. We show that 1000 Hz frequency, 40 nm amplitude vibration reduces osteoclast formation and activity in human mononuclear CD14+ blood cells. Additionally, this nanoscale vibration both enhances osteogenesis and reduces osteoclastogenesis in a co-culture of primary human bone marrow stromal cells and bone marrow hematopoietic cells. Further, we use metabolomics to identify Akt (protein kinase C) as a potential mediator. Akt is known to be involved in bone differentiation via transforming growth factor beta 1 (TGFß1) and bone morphogenetic protein 2 (BMP2) and it has been implicated in reduced osteoclast activity via Guanine nucleotide-binding protein subunit α13 (Gα13). With further validation, our nanovibrational bioreactor could be used to help provide humanised 3D models for drug screening.

14.
Orthop J Sports Med ; 9(11): 23259671211029208, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34778469

RESUMO

Background: There is a paucity of data regarding osteochondral lesions of the tibial plafond (OLTPs), in part because they are far less common than osteochondral lesions of the talus. Purpose: To evaluate the topographical characteristics of OLTPs and outcomes after surgical intervention, while analyzing the level of evidence (LOE) and quality of evidence (QOE) of the included studies. Study Design: Systematic review; Level of evidence, 4. Methods: A systematic review of the MEDLINE, EMBASE, and Cochrane Library databases was performed in accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Studies reporting clinical data for OLTPs were included. The LOE and QOE of the included studies were evaluated using a 5-level grading system and the modified Coleman Methodology Score, respectively. Results: Included were 20 studies with 426 OLTPs; 4 studies were LOE 2 and 16 studies were LOE 4. Overall, 86.7% of OLTPs were associated with a traumatic history and/or previous ankle sprain. OLTPs were most commonly located in the centromedial region of the tibial plafond (30.4%), with the fewest number of OLTPs found in the anteromedial region of the tibial plafond (3.9%). In 17 of the studies, a total of 46.9% of OLTPs were associated with coexisting osteochondral lesions of the talus. The most frequently used surgical technique to treat OLTPs was microfracture, which resulted in good clinical outcomes at midterm follow-up. Conclusion: The results of this systematic review indicated that OLTPs are frequently preceded by ankle trauma and are often associated with coexisting osteochondral lesions of the talus. Clinical outcomes after arthroscopic intervention appear to produce good results in the midterm, but the low LOE, poor QOE, marked heterogeneity, and underreporting of the data confound any recommendation based on this systematic review.

15.
Sci Data ; 8(1): 261, 2021 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-34608148

RESUMO

This paper describes a global monthly gridded Sea Surface Temperature (SST) and Sea Ice Concentration (SIC) dataset for the period 1000-1849, which can be used as boundary conditions for atmospheric model simulations. The reconstruction is based on existing coarse-resolution annual temperature ensemble reconstructions, which are then augmented with intra-annual and sub-grid scale variability. The intra-annual component of HadISST.2.0 and oceanic indices estimated from the reconstructed annual mean are used to develop grid-based linear regressions in a monthly stratified approach. Similarly, we reconstruct SIC using analog resampling of HadISST.2.0 SIC (1941-2000), for both hemispheres. Analogs are pooled in four seasons, comprising of 3-months each. The best analogs are selected based on the correlation between each member of the reconstructed SST and its target. For the period 1780 to 1849, We assimilate historical observations of SST and night-time marine air temperature from the ICOADS dataset into our reconstruction using an offline Ensemble Kalman Filter approach. The resulting dataset is physically consistent with information from models, proxies, and observations.

16.
Int J Biol Macromol ; 192: 197-209, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34624381

RESUMO

Nanotechnology has proven as progressive technology that enables to contribute, develop several effective and sustainable changes in food products. Incorporating nanomaterials like TiO2, SiO2, Halloysite nano clay, Copper sulfide, Bentonite nano clay, in carrageenan to develop innovative packaging materials with augmented mechanical and antimicrobial properties along with moisture and gas barrier properties that can produce safe and healthy foods. Intervention of carrageenan-based bio-nanocomposites as food packaging constituents has shown promising results in increasing the shelf stability and food quality by arresting the microbial growth. Nanomaterials can be incorporated within the carrageenan for developing active packaging systems for continuous protection of food products under different storage environments from farm to the fork to ensure quality and safety of foods. Carrageenan based bio nanocomposite packaging materials can be helpful to reduce the environmental concerns due to their high biodegradability index. This review gives insight about the current trends in the applications of carrageenan-based bio nanocomposites for different food packaging applications.

17.
Semin Dial ; 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34642963

RESUMO

BACKGROUND: Access flow dysfunction, often associated with stenosis, is a common problem in hemodialysis access and may result in progression to thrombosis. Timely identification of accesses in need of evaluation is critical to preserving a functioning access. We hypothesized that a risk score using measurements obtained from the Vasc-Alert surveillance device could be used to predict subsequent interventions. METHODS: Measurement of five factors over the preceding 28 days from 1.46 million hemodialysis treatments (6163 patients) were used to develop a score associated with interventions over the subsequent 60 days. The score was validated in a separate dataset of 298,620 treatments (2641 patients). RESULTS: Interventions in arteriovenous fistulae (AVF; n = 4125) were much more common in those with the highest score (36.2%) than in those with the lowest score (11.0). The score also was strongly associated with interventions in patients with an arteriovenous graft (AVG; n = 2,038; 43.2% vs. 21.1%). There was excellent agreement in the Validation datasets for AVF (OR = 2.67 comparing the highest to lowest score) and good agreement for AVG (OR = 1.92). CONCLUSIONS: This simple risk score based on surveillance data may be useful for prioritizing patients for physical examination and potentially early referral for intervention.

18.
Iperception ; 12(5): 20416695211047259, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34707801

RESUMO

In his extensive writing about pictures, James J. Gibson offered perspective formulae for square tiles projecting trapezoids onto a picture plane, foreshortening to zero height with distance. I reverse the claim: as distance decreases, the trapezoids increase to infinite height, in marginal distortion, or forelengthening. I also reverse the direction of projection. Usually considered to be incoming, from the distant tile to the picture plane, in reverse-outgoing-the tiles have directions from the center of projection, with implications for haptics and people who are blind. A drawing of a cube illustrates the argument. It is by an adult who is blind. It includes foreshortening, and shows directions of surfaces from a vantage point.

19.
Am J Sports Med ; 49(14): 3876-3886, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34710335

RESUMO

BACKGROUND: Biological adjuvants are used after a musculoskeletal injury to improve healing, decrease inflammation, and restore joint homeostasis. Work on 1 such adjuvant, platelet-rich plasma (PRP), has suggested a positive effect when introduced during cartilage repair. However, it remains unknown whether healing osteochondral injuries benefit from serial PRP injections. PURPOSE: To evaluate the effects of serial PRP injections versus a single PRP injection on reparative cartilaginous tissue, subchondral bone remodeling, and the expression of inflammatory cytokines in joint synovium. STUDY DESIGN: Controlled laboratory study. METHODS: A total of 48 New Zealand White rabbits were randomly assigned to receive 1 (1P), 2 (2P), or 3 (3P) PRP injections. Cylindrical full-thickness cartilage defects (2.9 × 2.9 mm) with microdrillings (0.6-mm diameter) were created on the medial condyles of both knees. PRP was injected into the right knee after closure (groups 1P, 2P, and 3P), at 2 weeks after surgery (groups 2P and 3P), and at 4 weeks after surgery (group 3P). The left knees did not receive any PRP injections. A total of 6 rabbits in each group were euthanized at 3, 6, and 12 weeks postoperatively. Cartilage repair tissue was assessed using the Goebel macroscopic and modified International Cartilage Regeneration & Joint Preservation Society (ICRS) histological scoring systems. Subchondral bone remodeling was evaluated by micro-computed tomography analysis (micro-CT). Inflammatory cytokine levels were assessed by quantitative polymerase chain reaction. RESULTS: No significant differences were found for the mean macroscopic score between the PRP groups at 12 weeks (control, 6.1 ± 3.3; group 1P, 3.4 ± 2.7; group 2P, 4.2 ± 2.9; group 3P, 0.7 ± 1.5). All PRP groups had a significantly higher mean modified ICRS histological score compared with the control group, but no significant difference was found among the PRP groups. No significant differences were seen in outcomes for the tested micro-CT parameters or cytokine expression levels. CONCLUSION: Serial PRP injections conferred no apparent advantage over single injections according to evaluations of the macroscopic and histological appearance of the cartilaginous tissue, subchondral bone healing, and inflammatory cytokine expression levels in the synovium. CLINICAL RELEVANCE: The use of PRP as a biological adjuvant to bone marrow stimulation for osteochondral lesions has the potential to enhance the quality of regenerative cartilaginous tissue. We recommend only a single PRP injection if the use of PRP is indicated by the operating surgeon as an adjuvant therapy for osteochondral lesions.

20.
Materials (Basel) ; 14(18)2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34576679

RESUMO

Ironsand is an abundant and inexpensive magnetic mineral resource. However, the magnetic properties of unprocessed ironsand are often inadequate for any practical applications. In this work, the applicability of ironsand for use as a component in a soft magnetic composite for large-scale inductive power transfer applications was investigated. After magnetic separation, the chemical, structural and magnetic properties of ironsand sourced from different locations were compared. Differences observed in the DC magnetic properties were consistent with changes in the chemical compositions obtained from X-ray Absorption Near-Edge Spectroscopy (XANES), which suggests varying the titanohematite to titanomagnetite content. Increased content in titanomagnetite and magnetic permeability correlated well with the total Fe content in the materials. The best-performing ironsand with the highest permeability and lowest core losses was used alongside Mn,Zn-Ferrite particles (ranging from ∼100 µm to 2 mm) to fabricate toroid cores with varying magnetic material loading. It was shown that ironsand can be used to replace up to 15 wt.% of the magnetic materials with minimal impact on the composite magnetic performance, thus reducing the cost. Ironsand was also used as a supporting material in a single-rail wireless power transfer system, effectively increasing the power transfer, demonstrating potential applications to reduce flux leakage.

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