Synergistic Effect of Polyvinyl Alcohol and Copovidone in Itraconazole Amorphous Solid Dispersions.

Purpose: The first objective is to evaluate the feasibility of melt-extruding polyvinyl alcohol-based amorphous solid dispersions for oral drug delivery. The second objective is to investigate the miscibility between polyvinyl alcohol 4-88 and copovidone, and to characterize the properties of ternary itraconazole amorphous solid dispersions comprising both polymers.

Methods: Samples were prepared using a co-rotating, twin-screw extruder.

Physicochemical properties of direct compression tablets with spray dried and ball milled solid dispersions of tadalafil in PVP-VA.

The aim of this research was to develop immediate release tablets comprising solid dispersion (IRSDTs) of tadalafil (Td) in a vinylpyrrolidone and vinyl acetate block copolymer (PVP-VA), characterized by improved dissolution profiles. The solid dispersion of Td in PVP-VA (Td/PVP-VA) in a weight ratio of 1:1 (w/w) was prepared using two different processes i.e.

Three-dimensional printed polycaprolactone-based scaffolds provide an advantageous environment for osteogenic differentiation of human adipose-derived stem cells.

The capacity of bone grafts to repair critical size defects can be greatly enhanced by the delivery of mesenchymal stem cells (MSCs). Adipose tissue is considered the most effective source of MSCs (ADSCs); however, the efficiency of bone regeneration using undifferentiated ADSCs is low. Therefore, this study proposes scaffolds based on polycaprolactone (PCL), which is widely considered a suitable MSC delivery system, were used as a three-dimensional (3D) culture environment promoting osteogenic differentiation of ADSCs.

Osteocyte Lacunae Density in Dentine-Induced Ectopic Bone.

The frequency of osteocytic lacunae, expressed as mean lacunae number per 1000 μm2 of measured bone, evaluated 65 days post intramuscular implantation of demineralized incisors is higher (1.10 ± 0.19) than in femoral (orthotopic) bone (0.

Physical stability of solid dispersions with respect to thermodynamic solubility of tadalafil in PVP-VA.

The aim of this paper was to evaluate physical stability of solid dispersions in respect to the drug, tadalafil (Td), in vinylpyrrolidone and vinyl acetate block copolymer (PVP-VA). Nine solid dispersions of Td in PVP-VA (Td/PVP-VA) varied in terms of quantitative composition (1:9-9:1, w/w) were successfully produced by spray-drying. Their amorphous nature, supersaturated character and molecular level of mixing (a solid solution structure) were subsequently confirmed using DSC, PXRD, SEM and calculation of Hansen total solubility parameters.

Physicochemical properties of tadalafil solid dispersions - Impact of polymer on the apparent solubility and dissolution rate of tadalafil.

To improve solubility of tadalafil (Td), a poorly soluble drug substance (3μg/ml) belonging to the II class of the Biopharmaceutical Classification System, its six different solid dispersions (1:1, w/w) in the following polymers: HPMC, MC, PVP, PVP-VA, Kollicoat IR and Soluplus were successfully produced by freeze-drying. Scanning electron microscopy showed a morphological structure of solid dispersions typical of lyophilisates. Apparent solubility and intrinsic dissolution rate studies revealed the greatest, a 16-fold, increase in drug solubility (50μg/ml) and a significant, 20-fold, dissolution rate enhancement for the Td/PVP-VA solid dispersion in comparison with crystalline Td.

Expression of bone morphogenetic protein-2 and -7 in urinary bladder cancer predicts time to tumor recurrence.

Introduction: Urinary bladder cancer patients who have undergone transurethral resection of bladder tumor (TURBT) are at risk of recurrence. This study aims to correlate the level of bone morphogenetic protein (BMP) expression with urothelial carcinoma invasiveness, TNM stage and time to recurrence after TURBT.

Material And Methods: In 33 specimens of healthy transitional epithelium and 42 of urothelial carcinoma, BMP2, BMP4 and BMP7 expression was determined by real-time polymerase chain reaction.

Incidence of bone formation by whole bone marrow cell suspensions and by its stromal cell cultures injected into kidney parenchyma of Balb/c mice.

The evaluation of incidence of bone formation by whole syngeneic bone marrow cell suspension and by bone marrow stromal cell cultured in vitro injection into kidney parenchyma was done. Bone tissue was found in 26 kidneys out of 100 injected with whole bone marrow cells suspension. Cultured stromal bone marrow cells grafted into kidney parenchyma produced ossicles in only 4 out of 101 injected kidneys.

Physical stability of the amorphous anticholesterol agent (ezetimibe): the role of molecular mobility.

The purpose of this paper is to examine the role of molecular mobility in the recrystallization process from the amorphous state of the anticholesterol drug ezetimibe. Both the molecular dynamics and crystallization kinetics have been studied using various experimental techniques, such as broadband dielectric spectroscopy (BDS), differential scanning calorimetry (DSC), and X-ray diffraction (XRD). Our investigations have shown that ezetimibe easily recrystallizes from the disordered state, both below and above its glass transition temperature (Tg = 336 K).

[The importance of lactoferrin in bone regeneration].

Lactoferrin is an iron-binding protein secreted by mammary gland, thus present in milk and in colostrum, which are a cheap and easy to obtain sources of this protein. Lactoferrin is also present in specific granules of neutrophils. Lactoferrin is a multifunctional agent involved, among others in the immune response and in the regulation of bone metabolism.

Are chondroclasts and osteoclasts identical?

Brief characteristics of cells termed "osteoclasts" and "chondroclasts" are outlined and reasons to consider them as the same cell type, able to resorb calcified matrix, are discussed.

The influence of amorphization methods on the apparent solubility and dissolution rate of tadalafil.

This study for the first time investigates the solubility and dissolution rate of amorphous tadalafil (Td)--a poorly water soluble chemical compound which is commonly used for treating the erectile dysfunction. To convert the crystalline form of Td drug to its amorphous counterpart we have employed most of the commercially available amorphization techniques i.e.

Fluvastatin influences hair color in C57BL/6 mice.

Our recent in vitro experiments suggest that fluvastatin may influence tyrosinase (key enzyme of melanogenesis) synthesis. The aim of the present study was to verify those findings in experiments, in vitro, in melanoma cell line, and in vivo, in mice. The expression of tyrosinase in B16F10 melanoma cell line, after induction of melanogenesis by UVB irradiation, was examined by Western blot analysis.

Osteogenic efficiency of demineralized and lyophylized xenogeneic bone and syngeneic dentine implants in mice.

Intramuscular implantation of demineralized and lyophilized rat bone matrix and murine lower incisors into thigh muscles of BALB/c mice results in deposits of bone adjacent to the implants, a phenomenon termed as ectopic osteogenesis. The yield of induced bone does not critically depend on the mass of implanted matrices, and thus on the quantity of bone morphogenetic proteins (BMPs) present in the implants. A positive correlation between bone matrix implant weight and the yield of induced bone was observed only 28 days post grafting, i.

Long-term preservation of Bone Morphogenetic Activity in stored demineralized murine incisors.

Demineralized bone or dentine implanted intramuscularly induce endochondral bone formation. This phenomenon, termed "bone induction" is triggered by non-collagenous signal molecules, named "Bone Morphogenetic Proteins" (BMPs), released from bone or dentine. Demineralization of bone/dentine prior their implantation facilitates the release of BMPs from the extracellular matrix allowing to reach a BMP threshold level needed to initiate the process of differentiation of mesenchymal cells towards an osteogenic/chondrogenic lineage.

Adipose mesenchymal stem cells. Their characteristics and potential application in tissue repair.

Mesenchymal stem cells, derived from adipose tissue do not differ substantially from mesenchymal stem cells isolated from bone marrow stroma. They are able to differentiate in differentiating culture medium into various cell type of mesodermal lineage, but also into cells of ectodermal type. Their potency to differentiate toward osteogenic and adipogenic lineage is promising to be a ready source of cells for tissue regeneration.

Effect of amorphization method on telmisartan solubility and the tableting process.

Telmisartan (TLM), a poorly water-soluble angiotensin II receptor antagonist in crystalline form, was transformed into the amorphous state by the melt quench technique, as well as a cryogenic grinding method, in order to improve its physiochemical properties. The chemical stability of TLM, that is, the tendency of the material to resist change or decomposition due to internal reaction, or due to the effects of air, heat, light, pressure, etc., during formation of the amorphous phase was assessed by monitoring high performance liquid chromatography.

The adipocyte component of bone marrow in heterotopic bone induced by demineralized incisor grafts.

The relative proportion of adipocytes to hematopoietic elements in the marrow of heterotopically induced bone evaluated 4-42 weeks post implantation of demineralized murine incisors was estimated by histological analysis of hematoxylin-eosin stained tissue sections. Using computerized image analysis of microphotographs,the proportion of nuclear cells vs. adipocytes was ascertained.

Skeletal muscle-derived fibroblast-like cells fail to enable HeLa cells to induce bone in the murine kidney.

HeLa cells fail to induce bone in murine kidneys, despite being highly chondro/osteogenic when implanted into thigh muscles. Bone induction in the kidneys failed also when HeLa cells were grafted together with skeletal-muscle-derived cell cultures. It is postulated that kidney parenchyma releases unidentified factcor(s) which prevent activation by inducer of cells termed Friedenstein's (1976) "inducible osteoprogenitor cells", while this hypothetical factor does not prevent further differentiation of"determined osteoprogenitor cells", thus allowing bone to form in the renal parenchyma.

Haematopoietic and osteogenic bone marrow stem cells.

This article discusses the concept of a common stem cell for bone marrow stromal cells and haematopoietic cells. Until recently it was generally accepted that bone marrow contains two types of stem cells. One is the haemopoietic stem cell; the second one, the mesenchymal stem cell or stromal stem cell, gives rise to the stromal compartment of the marrow.

[Regulation of the differentiation of bone marrow mesenchymal stem cells into osteoblastic and adipogenic lineage].

The role of transcription factors and signalling pathways important for differentiation of bone marrow mesenchymal stem cell differentiation toward osteogenic and adipogenic lineage are briefly outlined.

Effects of time of initial exposure to MSV sarcoma on bone induction by dentine matrix implants and on orthotopic femora.

HCl-demineralized murine lower incisors were implanted intramuscularly into syngeneic BALB/c mice to induce heterotopic osteogenesis. Implants were exposed at the early, preosteogenic stage (4), or at the later, osteogenic stage (12) to the Moloney sarcoma virus (MSV), which within 3-4 days results in a sarcoma. The yield of bone induction was determined by weight of dry bone mass following NaOH hydrolysis of soft tissues.

Peripheral blood and lymphatic organs in BALB/c mice during the progressive and regressive phases of Moloney sarcoma development.

Blood cell counts, differential blood cell counts and weights of the spleen and peripheral lymph nodes draining the area of lesions induced by Moloney sarcoma virus inoculation into the quadriceps shank muscles of inbred BALB/c mice were examined at various stages of tumor development and regression. The blood cell count remained constant through the observation period up to 27 days post tumor development and regression. Differential counts revealed some changes in the cellular composition of the peripheral blood.