Targeted deletion of Fgf9 in tendon disrupts mineralization of the developing enthesis

The enthesis is a transitional tissue between tendon and bone that matures postnatally. The development and maturation of the enthesis involve cellular processes likened to an arrested growth plate. In this study, we explored the role of fibroblast growth factor 9 (Fgf9), a known regulator of chondrogenesis and vascularization during bone development, on the structure and function of the postnatal enthesis. First, we confirmed spatial expression of Fgf9 in the tendon and enthesis using in situ hybridization. We then used Cre-lox recombinase to conditionally knockout Fgf9 in mouse tendon and enthesis (Scx-Cre) and characterized enthesis morphology as well as mechanical properties in Fgf

Loss of Fgfr1 and Fgfr2 in Scleraxis-lineage cells leads to enlarged bone eminences and attachment cell death

BACKGROUND Tendons and ligaments attach to bone are essential for joint mobility and stability in vertebrates. Tendon and ligament attachments (ie, entheses) are found at bony protrusions (ie, eminences), and the shape and size of these protrusions depend on both mechanical forces and cellular cues during growth. Tendon eminences also contribute to mechanical leverage for skeletal muscle. Fibroblast growth factor receptor (FGFR) signaling plays a critical role in bone development, and Fgfr1 and Fgfr2 are highly expressed in the perichondrium and periosteum of bone where entheses can be found. RESULTS AND CONCLUSIONS We used transgenic mice for combinatorial knockout of Fgfr1 and/or Fgfr2 in tendon/attachment progenitors (ScxCre) and measured eminence size and shape. Conditional deletion of both, but not individual, Fgfr1 and Fgfr2 in Scx progenitors led to enlarged eminences in the postnatal skeleton and shortening of long bones. In addition, Fgfr1/Fgfr2 double conditional knockout mice had more variation collagen fibril size in tendon, decreased tibial slope, and increased cell death at ligament attachments. These findings identify a role for FGFR signaling in regulating growth and maintenance of tendon/ligament attachments and the size and shape of bony eminences

Factors Influencing the Hope Level of Iranian English Major Students

This study aimed to measure the hope level of Iranian English-major students and also to find out if their gender, academic degree, years spent in a program, and GPA were associated with their hope level. To reach these aims, the Integrative Hope Scale developed by Sharpe, McElheran, and Whelton (2017) was modified, checked for validity, and piloted. Then, it was distributed among 206 English-major students doing their BA, MA, and PhD in different universities of Iran, chosen through random and snowball sampling. The analysis of the data through non-parametric tests showed that although undergraduate and postgraduate students enjoyed a higher level of hope, there was no significant difference in the students’ hope level based on their academic degree. Furthermore, no significant relationship was found between students’ levels of hope, on the one hand, and their GPA and the number of years spent in a program, on the other hand. However, there was a significant difference between male and female students, with males having a higher level of hope

Partial-width injuries of the rat rotator cuff heal with fibrosis

<p><b>Purpose</b>: Identify the healing outcomes following a partial-width, full-thickness injury to the rotator cuff tendon-bone attachment and establish if the adult attachment can regenerate the morphology of the healthy attachment.</p> <p><b>Hypothesis</b>: We hypothesized that a partial-width injury to the attachment would heal via fibrosis and bone remodeling, resulting in increased cellularity and extra-cellular matrix deposition, reduced bone volume (BV), osteoclast presence, and decreased collagen organization compared to shams.</p> <p><b>Materials and Methods</b>: A partial-width injury was made using a biopsy punch at the center one-third of the rat infraspinatus attachment. Contralateral limbs underwent a sham operation. Rats were sacrificed at 3 and 8 weeks after injury for analyses. Analyses performed at each time point included cellularity (Hematoxylin & Eosin), ECM deposition (Masson’s Trichrome), BV (micro-computed tomography; microCT), osteoclast activity (Tartrate Resistant Acid Phosphatase; TRAP), and collagen fibril organization (Picrosirius Red). Injured and sham shoulders were compared at both 3 and 8 weeks using paired, two-way ANOVAs with repeated measures (Sidak’s correction for multiple comparisons).</p> <p><b>Results</b>: Cellularity and ECM deposition increased at both 3 and 8 weeks compared to sham contralateral attachments. BV decreased and osteoclast presence increased at both 3 and 8 weeks compared to sham contralateral limbs. Collagen fibril organization was reduced at 3 weeks after injury compared to 3-week sham attachments.</p> <p><b>Conclusions</b>: These findings suggest that a partial-width injury to the rotator cuff attachment does not fully regenerate the native structure of the healthy attachment. The injury model healed via scar-like fibrosis and did not propagate into a full-width tear after 8 weeks of healing.</p

SD1000: High Sustained Viral Response Rate in 1361 Patients With Hepatitis C Genotypes 1, 2, 3, and 4 Using a Low-cost, Fixed-dose Combination Tablet of Generic Sofosbuvir and Daclatasvir: A Multicenter, Phase III Clinical Trial

Background. The combination of sofosbuvir and daclatasvir is a potent, pangenotypic regimen suitable for mass-scale hepatitis C treatment, especially in resource-limited countries where newer, expensive combinations are not available. This combination has been widely tested on genotype 4. However, Phase III trials of this combination in other genotypes have been cost prohibitive. With the introduction of generic, low-cost sofosbuvir and daclatasvir, large-scale studies in resource-limited countries are now possible. Methods. Sofosbuvir at 400 mg and daclatasvir at 60 mg were coformulated into a fixed-dose combination (FDC) tablet (Sovodak, Rojan Pharma, Tehran, Iran). Patients from 46 centers were dosed for 12 or 24 weeks with or without ribavirin, in line with existing guidelines. Responses to treatment were evaluated 12 weeks after the end of treatment (for a sustained virological response at Week 12; SVR12). Results. There were 1361 patients recruited. Overall, the patients were 21% female, with a mean age of 50 years; 39% were cirrhotic; 22% were treatment-experienced; 47% were genotype 1, 41% were genotype 3, and 2% were other genotypes. The genotype was not known in 10% of the patients. The intention-to-treat and per-protocol SVR12 rates were 94.7% and 98.8%, respectively. The safety profile was unremarkable, treatment was well tolerated, and compliance with the single-tablet regimen was excellent. Conclusions. The treatment with FDC of sofosbuvir and daclatasvir achieved high SVR12 rates, equivalent to those seen in Phase III trials of other pangenotypic options, and has been conducted at a similar scale in a representative, real-world population at a cost of under $100 per patient, which makes this combination suitable for elimination protocols in resource-limited countries. Keywords:sofosbuvir; daclatasvir; Hepatitis C; sustained virological response; generic drug