Purpose: To demonstrate experimentally, with the use of pig knee joints, that the posterior meniscofemoral ligament (PML) stabilizes the lateral meniscus (LM).
Methods: Amputated stumps of the knee joints of Yorkshire pigs, which are anatomically similar to human knee joints, were used. The PML was intact or was cut according to 1 of 6 different conditions: (1) intact PML with intact LM, (2) intact PML with a radial tear of the posterior horn of the LM, (3) intact PML with total lateral meniscectomy, (4) cut PML with intact LM, (5) cut PML with a radial tear of the posterior horn of the LM, and (6) cut PML with total lateral meniscectomy. Pressure-sensitive film was inserted beneath the lateral femoral condyle, an axial load of 150 kg was placed on the knee joint with a universal testing machine, and the pressed area and maximum and average pressures were measured with the Prescale Imaging Analysis System (Fujifilm Medical Systems, Stamford, CT).
Results: With an intact PML, no difference was seen between the intact meniscus and the radial tear of the posterior horn of the LM in pressed area and maximum and average pressures. With a cut PML, pressure concentration, detected as significantly reduced pressed area and increased maximum and average pressures, was observed, regardless of the condition of the LM.
Conclusions: PML of the pig stabilized the LM under an axial load, and an intact PML yielded results similar to those observed in total lateral meniscectomy. Our findings suggest that posterior horn tears of the LM, which are rarely symptomatic, may be caused by stabilizing of the lateral meniscus by the PML against the load placed on the knee joint.
Clinical Relevance: Findings suggest that the PML, lateral side, stabilizes the LM when the ligament is intact. Even when a tear of the meniscus occurs, no increased localized pressure areas appear on the meniscus; this may explain why these tears are rarely symptomatic.
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http://dx.doi.org/10.1016/j.arthro.2006.04.081 | DOI Listing |
Commun Biol
October 2024
Department of Physics and Astronomy "Ettore Majorana", University of Catania, Catania, Italy.
To understand how oncogenes affect genome organization, it is essential to visualize fundamental processes such as DNA replication and transcription at high resolution in intact cells. At the same time, it is important to determine the progression of the cell along the cell cycle, as cell cycle regulation is crucial for the control of cell proliferation and oncogenesis. Here, we present a super-resolution imaging-based method to analyze single cell nuclei sorted according to specific phases of the cell cycle.
View Article and Find Full Text PDFCureus
July 2024
Internal Medicine, Max Smart Super Speciality Hospital, Saket, New Delhi, IND.
Mult Scler Relat Disord
July 2024
Abreos Biosciences, 3550 General Atomics Court(,) G02/rm140, San Diego, CA, USA.
Background: Natalizumab (NAT) pharmacokinetics and pharmacodynamics are complicated by arm exchange with endogenous IgG4, resulting in a mixture of a more potent intact, bivalent form and a less potent, functionally monovalent form. Total NAT and endogenous IgG4 concentrations vary considerably across patients. This study assessed the concentration of intact NAT, and how it relates to total NAT and endogenous IgG4 levels in blood and saliva.
View Article and Find Full Text PDFJ Am Soc Mass Spectrom
June 2024
Biomolecular Mass Spectrometry & Proteomics, Bijvoet Center for Biomolecular Research & Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands.
Endogenous antibodies, or immunoglobulins (Igs), abundantly present in body fluids, represent some of the most challenging samples to analyze, largely due to the immense variability in their sequences and concentrations. It has been estimated that our body can produce billions of different Ig proteins with different isotypes, making their individual analysis seemingly impossible. However, recent advances in protein-centric proteomics using LC-MS coupled to Orbitrap mass analyzers to profile intact Fab fragments formed by selective cleavage at the IgG-hinge revealed that IgG repertoires may be less diverse, albeit unique for each donor.
View Article and Find Full Text PDFBiophys J
November 2022
Department of Physics and Astronomy "Ettore Majorana", University of Catania, Catania, Italy; Nanoscopy and NIC@IIT, CHT Erzelli, Istituto Italiano di Tecnologia, Genoa, Italy. Electronic address:
The molecular mechanisms that underlie oncogene-induced genomic damage are still poorly understood. To understand how oncogenes affect chromatin architecture, it is important to visualize fundamental processes such as DNA replication and transcription in intact nuclei and quantify the alterations of their spatiotemporal organization induced by oncogenes. Here, we apply superresolution microscopy in combination with image cross correlation spectroscopy to the U937-PR9 cell line, an in vitro model of acute promyelocytic leukemia that allows us to activate the expression of the PML-RARα oncogene and analyze its effects on the spatiotemporal organization of functional nuclear processes.
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