Viscosupplementation with hyaluronic acid in the treatment for cartilage lesions: a review of current evidence and future directions

Diseases involving the articular cartilage are one of the leading causes of physical impairment among the adult population. While surgical technique and advancement have allowed us effective means at treating these diseases, this is not without significant risk and morbidity. With a very solid safety profile, viscosupplementation with hyaluronic acid (HA) derivatives has become an excellent modality for treating diseased articular cartilage. Recent literature supports the use of HA not only in the management of the pain associated with osteoarthritis but also as a disease-modifying agent as well. Further studies have started to define exciting new roles for viscosupplementation in the treatment for acute injuries to the joint microenvironment.     

Techniques in recurrent giant cell tumour of the first metatarsal in adolescents – A rare report of 2 cases

Giant cell tumour of the foot is very rare. Very few cases of first metatarsal giant cell tumour were reported. We report two cases of recurrent giant cell tumour in adolescent patients. One was treated with wide excision and fibula grafting. The second patient underwent Boyd's amputation because of superceded infection. Both had no pain, recurrence at the end of final follow up. Recurrent giant cell tumour of the first metatarsal in adolescents and its management is not described in English literature to the best of our knowledge.     

Safe surgical technique: reconstruction of the sternoclavicular joint for posttraumatic arthritis after posterior sternoclavicular dislocation

Posttraumatic sternoclavicular arthritis related to chronic ligamentous instability after posterior sternoclavicular dislocation represents a rare but challenging problem. The current article in the Journal’s “Safe Surgical Technique” series describes a successful salvage procedure by partial resection of the medial clavicle and ligamentous reconstruction of the sternoclavicular joint with a figure-of-eight semitendinosus allograft interposition arthroplasty.     

Reciprocal relationships between orthodontics and periodontics in esthetic treatments

The objective of this article is to review various unsightly periodontal defects and the treatments that have previously been used to eliminate them in order to establish guidelines for future therapy. The inter-relationship between orthodontic and periodontal disciplines is well established and needs no defense here. Periodontal tissues change throughout life and the same is true for the smile. The periodontium is an essential component of the appearance of the face as well as the lips. These are dynamic esthetic criteria while the gingiva and the static character of the dentition also contribute to the character of an individual's smile. In order to conduct orthodontic therapy most effectively it is essential that orthodontists and periodontists utilize a coordinated approach. From the beginning, they must establish an etiological diagnosis of any esthetic defects that will insure that their joint therapy is conducted appropriately and at the proper moment.     

A novel approach to evaluating the benefit of post-urinary tract infection renal ultrasonography,using decision curve analysis

Background

The benefit of post-urinary tract infection (UTI) sonography to detect clinically significant renal abnormalities remains a subject open to debate. Decision curve analysis (DCA) is a novel method for evaluating the clinical usefulness of diagnostic tests. Our objective was to determine, using DCA, the benefit of post-UTI sonography and of post-UTI sonography with biological markers of inflammation to predict the risk of recurrence of febrile UTI in children aged 2 to 24 months without known uropathy.

Methods

We retrospectively analyzed all children aged 2 to 24 months, without known uropathy, who presented with a first episode of febrile UTI between 2009 and 2012 and followed them for 30 months. We then used DCA to estimate the benefit of post-UTI sonography or post-UTI sonography + biological markers of inflammation for detecting the risk of recurrence.

Results

A total of 318 children [144 boys (45.3 %) and 174 girls (54.7 %)], with a mean age of 6.9?±?5.6 months, were identified. Of these, 210 children presented with a significant inflammation [66.2 %; 95 % confidence interval (CI) 61.0–71.4], and 30 (9.4 %; 95 % CI 6.2–12.6) presented with abnormal post-UTI sonographic findings. Eighteen (5.7 %; 95 % CI 3.1–8.2) children presented with recurrent UTI at 30 months.

Conclusions

There were significantly more recurrences in those children who presented with abnormal sonographic findings than in those who did not (relative risk?7.68; 95 % CI 3.03–19.46). However, taking into account the effect of false-positives and false negatives, the DCA revealed that for threshold probabilities of >30 %, at which patients/doctors are concerned about unnecessary interventions (whether tests or treatments), neither post-UTI sonography nor post-UTI sonography + biological markers of inflammation have sufficient value to improve care.

     

Expression of the gp150 maedi visna virus envelope precursor protein by mammalian expression vectors

There are very few previous reports of expression of native full-length maedi visna virus (MVV) Env gp150 protein in the literature. Therefore the use of different plasmid and viral expression vectors to obtain full-length gp150 was investigated. A mammalian expression plasmid, pN3-Env, was constructed containing the MVV env gene encoding the precursor protein gp150 Env. The functionality of the recombinant plasmid was tested for expression in HEK293 cells. A recombinant modified vaccinia Ankara virus, MVA-Env, with expression detected in avian cells was also made. The expression of the MVV gp150 Env precursor protein was shown for the first time upon transfection of the eukaryotic HEK293 cells by the pN3-Env plasmid DNA as demonstrated by Western blot analysis. These plasmid or viral expression vectors are of potential use in MVV vaccines.     

PDGF Receptor Signaling in Osteoblast Lineage Cells Controls Bone Resorption Through Upregulation of Csf1 Expression

The physiological functions of platelet-derived growth factor receptors (PDGFRs) α and β in osteoblast biology and bone metabolism remain to be established. Here, we show that PDGFRA and PDGFRB genes are expressed by osteoblast-lineage canopy and reversal cells in close proximity to PDGFB-expressing osteoclasts within human trabecular bone remodeling units. We also report that, although removal of only one of the two PDGFRs in Osterix-positive cells does not affect bone phenotype, suppression of both PDGFRs in those osteoblast lineage cells increases trabecular bone volume in male mice as well as in female gonad-intact and ovariectomized mice. Furthermore, osteoblast lineage-specific suppression of PDGFRs reduces Csf1 expression, bone marrow level of macrophage colony-stimulating factor (M-CSF), number of osteoclasts, and, therefore, bone resorption, but does not change bone formation. Finally, abrogation of PDGFR signaling in osteoblasts blocks PDGF-induced ERK1/2-mediated Csf1 expression and M-CSF secretion in osteoblast cultures and calcitriol-mediated osteoclastogenesis in co-cultures. In conclusion, our results indicate that PDGFR signaling in osteoblast lineage cells controls bone resorption through ERK1/2-mediated Csf1 expression. © 2020 American Society for Bone and Mineral Research (ASBMR).