The application of barrier membranes in guided bone regeneration (GBR) has become a commonly used surgical technique in periodontal research. The objectives of this study were to evaluate the in vitro biocompatibility and osteogenic differentiation of mesenchymal stem cells (MSCs) on two different collagenous coatings (nano electrospun fibrous vs. solid wall) of bilayered collagen/chitosan membrane and their histological evaluation on bone regeneration in rabbit calvarial defects. It was found that chitosan-nano electrospun collagen (CNC) membranes had higher proliferation/metabolic activity compared to the chitosan-collagen (CC) and pristine chitosan membranes. The qRT-PCR analysis demonstrated the CNC membranes induced significant expression of osteogenic genes (Osteocalcin, RUNX2 and Col-α1) in MSCs. Moreover, higher calcium content and alkaline phosphatase activity of MSCs were observed compared to the other groups. Histologic and histomorphometric evaluations were performed on the uncovered (negative control) as well as covered calvarial defects of ten adult white rabbits with different membranes (CNC, CC, BioGide (BG, positive control)) at 1 and 2 months after surgery. More bone formation was detected in the defects covered with CNC and BG membranes than those covered by CC and the negative control. No inflammation and residual biomaterial particles were observed on the membrane surface or in the surrounding tissues in the surgical areas. These results suggest that bilayer CNC membrane can have the potential for use as a GBR membrane material facilitating bone formation.

Medicinal plants as a therapeutic agent with osteogenic properties can enhance fracture-healing process. In this study, the osteo-inductive potential of Asian Panax Ginseng root extract within electrospun polycaprolactone (PCL) based nanofibers has been investigated. Scanning electron microscopy images revealed that all nanofibers were highly porous and beadles with average diameter ranging from 250 to 650 nm. The incorporation of ginseng extract improved the physical characteristics (i.e., hydrophilicity) of PCL nanofibers, as well as the mechanical properties. Although ginseng extract increased the degradation rate of pure PCL nanofibers, the porous structure and morphology of fibers did not change significantly after 42 days. It was found that nanofibrous scaffolds containing ginseng extract had higher proliferation (up to ~1.5 fold) compared to the pristine PCL. The qRT-PCR analysis demonstrated the addition of ginseng extract into PCL nanofibers induced significant expression of osteogenic genes (Osteocalcin, Runx-2 and Col-1) in MSCs in a concentration dependent manner. Moreover, higher calcium content, alkaline phosphatase activity and higher mineralization of MSCs were observed compared to the pristine PCL fibers. Our results indicated the promising potential of ginseng extract as an additive to enhance osteo-inductivity, mechanical and physical properties of PCL nanofibers for bone tissue engineering application.

In periodontics, osteoconductive biodegradable guided bone regeneration (GBR) membranes with acceptable physico-mechanical properties are required to fix alveolar bone defects. The objectives of the present study were to produce and characterize a novel co-polyester—poly (butylene succinate-co-glycolate) (PBSGL), and fabricate a PBSGL membrane by electrospinning. We then aimed to evaluate the in vitro effect of the glycolate ratio on the biocompatibility and osteogenic differentiation of mesenchymal stem cells (MSCs), and evaluate in vivo bone regeneration using these membranes in rabbit calvarial defects by histology. Increasing the glycolate ratio of electrospun PBSGL membranes resulted in better cell attachment, greater cell metabolic activity, and enhanced osteogenic potential at both transcriptional and translational levels. Histologic and histomorphometric evaluations revealed further that bone defects covered with fibers of higher glycolate ratios showed more bone formation, with no adverse inflammatory response. These results suggest that novel PBSGL electrospun nanofibers show great promise as GBR membranes for bone regeneration.

Cryptococcal endocarditis is an exceedingly rare entity associated with high mortality and morbidity. Hereby, we present a 37-year-old patient with underlying systemic lupus erythematosus and end-stage renal disease who was diagnosed with cryptococcal endocarditis involving native mitral valve. Her blood culture grew Cryptococcus neoformans. Echocardiography confirmed presence of vegetations and patient underwent mitral valve replacement and received appropriate anti-fungal treatment. Her course was further complicated by sternal wound dehiscence and infection of hemodialysis site as well as atrial flutter. Unfortunately, patient passed 2 weeks after discharge from hospital. C. neoformans is typically known to cause serious central nervous system. However, this pathogen can rarely cause serious infective endocarditis case particularly in immune compromised patients or those with prosthetic valves. Fungal endocarditis is usually treated with a combination of surgery and anti-fungal medications.

<p><strong>Objective</strong>. We describe a rare case of pseudohyponatremia in the setting of hypercholesterolemia caused by cholestasis due to metastatic liver disease and provide a review of the published cases in the literature.</p><p><strong>Case Report</strong>. We report a case of pseudohyponatremia in a 60-year-old man with rectal cancer with extensive metastasis to the liver. While assessing the patient for<br />hyponatremia, extremely elevated serum cholesterol with normal serum osmolality was detected leading to the diagnosis of pseudohyponatremia. This is one of very few reports of pseudohyponatremia in patients with elevated cholesterol in cholestatic liver disease.</p><p><strong>Conclusion</strong>. Hypercholesterolemia is an exceedingly rare cause for pseudohyponatremia. Although pseudohyponatremia per se does not carry a risk to the patient, the delay in diagnosis and treatment plans may pose additional risks. Pseudohyponatremia needs to be considered in patients with low sodium and co-existing cholestasis from metastatic liver disease.</p>