The antiviral mechanisms, effects, safety and adverse effects of chloroquine.

Chloroquine, a 4-aminoquinoline derivative, was initially used to treat malaria. It was later found to have immunomodulating, anti-infective, anti-thrombotic, anti-tumor, and metabolic effects. Recently, many studies have focused on the application of chloroquine in viral infections. Most in vitro studies suggested that chloroquine exerted some benefit in infections from viruses. However, animal experiment and clinical trials that attempted to use chloroquine in prevention or treatment of viral infections have reported disappointing results. It might be attributable to inadequate steady-state whole blood chloroquine concentration necessary for exerting its antiviral effects. A 16 µM/L steady-state whole blood concentration of chloroquine should suffice in antiviral treatment with minimal toxicity. Furthermore, chloroquine has both acute and cumulative toxicity. Hence, not only the appropriate treatment dose is crucial, the occurrence of adverse reactions should also be closely monitored and treated in time. Herein, we report the antiviral mechanisms, effects, safety and adverse effects of chloroquine.

Retraction Note: Structural simulation of adenosine phosphate via plumbagin and zoledronic acid competitively targets JNK/Erk to synergistically attenuate osteoclastogenesis in a breast cancer model.

This article has been retracted at the request of the authors. After publication, the authors found that in Figure 2B-a the first two images in the third row partly overlapped and that there is also overlap between the fourth and fifth image in the second row. The two images were taken from two adjacent wells, treated by ZA 0.3uM-CM or ZA 0.75uM-CM, with or without PL 1.25uM. This overlap may have been caused by mishandling in the imaging process when the authors made microscope observations and so the findings are no longer reliable. All authors agree to this retraction.

Surface-enrichment with hydroxyapatite nanoparticles in stereolithography-fabricated composite polymer scaffolds promotes bone repair.

Fabrication of composite scaffolds using stereolithography (SLA) for bone tissue engineering has shown great promises. However, in order to trigger effective bone formation and implant integration, exogenous growth factors are commonly combined to scaffold materials. In this study, we fabricated biodegradable composite scaffolds using SLA and endowed them with osteopromotive properties in the absence of biologics. First we prepared photo-crosslinkable poly(trimethylene carbonate) (PTMC) resins containing 20 and 40wt% of hydroxyapatite (HA) nanoparticles and fabricated scaffolds with controlled macro-architecture. Then, we conducted experiments to investigate how the incorporation of HA in photo-crosslinked PTMC matrices improved human bone marrow stem cells osteogenic differentiation in vitro and kinetic of bone healing in vivo. We observed that bone regeneration was significantly improved using composite scaffolds containing as low as 20wt% of HA, along with difference in terms of osteogenesis and degree of implant osseointegration. Further investigations revealed that SLA process was responsible for the formation of a rich microscale layer of HA corralling scaffolds. To summarize, this work is of substantial importance as it shows how the fabrication of hierarchical biomaterials via surface-enrichment of functional HA nanoparticles in composite polymer stereolithographic structures could impact in vitro and in vivo osteogenesis. STATEMENT OF SIGNIFICANCE: This study reports for the first time the enhance osteopromotion of composite biomaterials, with controlled macro-architecture and microscale distribution of hydroxyapatite particles, manufactured by stereolithography. In this process, the hydroxyapatite particles are not only embedded into an erodible polymer matrix, as reported so far in the literature, but concentrated at the surface of the structures. This leads to robust in vivo bone formation at low concentration of hydroxyapatite. The reported 3D self-corralling composite architecture provides significant opportunities to develop functional biomaterials for bone repair and tissue engineering.

Double-edged-sword effect of IL-1ß on the osteogenesis of periodontal ligament stem cells via crosstalk between the NF-κB, MAPK and BMP/Smad signaling pathways.

Microenvironmental conditions can interfere with the functional role and differentiation of mesenchymal stem cells (MSCs). Recent studies suggest that an inflammatory microenvironment can significantly impact the osteogenic potential of periodontal ligament stem cells (PDLSCs), but the precise effects and mechanisms involved remain unclear. Here, we show for the first time that interleukin-1ß (IL-1ß) has dual roles in the osteogenesis of PDLSCs at concentrations ranging from physiologically healthy levels to those found in chronic periodontitis. Low doses of IL-1ß activate the BMP/Smad signaling pathway to promote the osteogenesis of PDLSCs, but higher doses of IL-1ß inhibit BMP/Smad signaling through the activation of nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling, inhibiting osteogenesis. These results demonstrate that crosstalk between NF-κB, MAPK and BMP/Smad signaling mediates this dual effect of IL-1ß on PDLSCs. We also show that the impaired osteogenesis of PDLSCs results in more inflammatory cytokines and chemokines being released, inducing the chemotaxis of macrophages, which further clarifies the role of PDLSCs in the pathogenesis of periodontitis.

Methylprednisolone combined with low-dose indomethacin treating acute fibrinous and organizing pneumonia after a surgical resection of rectal adenocarcinoma: a case report and literature review.

OBJECTIVE: Acute Fibrinous and Organizing Pneumonia (AFOP) is a new pathologic pattern of acute lung injury characterized by the presence of intra-alveolar fibrin in the form of fibrin "balls" in a patchy distribution. CASE REPORT: A 65-years-old female after a surgical resection of rectal adenocarcinoma presented with typical manifestations of hospital-acquired pneumonia, but she didn't respond to the anti infective therapy. After an explicit diagnosis of AFOP via percutaneous needle lung biopsy, she got an impressive improvement with a long-term therapy of methylprednisolone and low-dose indomethacin. To date, a total of non-overlapped 45 individual AFOP cases and 4 single-center studies involving AFOP have been reported. The most common coexisting diseases are infections, connective tissue diseases and hematological diseases. Corticosteroids and immunosuppressants are the most common agents prescribed in AFOP. The prognosis of AFOP is unfavorable, associated with the pathologic characteristics and the clinical parameters. CONCLUSIONS: The immune system activated by infection may play an important role in the pathogenesis of AFOP. Low-dose indomethacin combined with methylprednisolone may be a new choice for AFOP treatment.

Structural simulation of adenosine phosphate via plumbagin and zoledronic acid competitively targets JNK/Erk to synergistically attenuate osteoclastogenesis in a breast cancer model.

The treatment of breast cancer-induced osteolysis remains a challenge in clinical settings. Here, we explored the effect and mechanism of combined treatment with zoledronic acid (ZA) and plumbagin (PL), a widely investigated component derived from Plumbago zeylanica, against breast cancer-induced osteoclastogenesis. We found that the combined treatment with PL and ZA suppressed cell viability of precursor osteoclasts and synergistically inhibited MDA-MB-231-induced osteoclast formation (combination index=0.28) with the abrogation of recombinant mouse receptor activator of nuclear factor-κB ligand (RANKL)-induced activation of NF-κB/MAPK (nuclear factor-κB/mitogen-activated protein kinase) pathways. Molecular docking suggested a putative binding area within c-Jun N-terminal kinase/extracellular signal-regulated kinase (JNK/Erk) protease active sites through the structural mimicking of adenosine phosphate (ANP) by the spatial combination of PL with ZA. A homogeneous time-resolved fluorescence assay further illustrated the direct competitiveness of the dual drugs against ANP docking to phosphorylated JNK/Erk, contributing to the inhibited downstream expression of c-Jun/c-Fos/NFATc-1 (nuclear factor of activated T cells, cytoplasmic, calcineurin-dependent 1). Then, in vivo testing demonstrated that the combined administration of PL and ZA attenuated breast cancer growth in the bone microenvironment. Additionally, these molecules prevented the destruction of proximal tibia, with significant reduction of tartrate-resistant acid phosphatase (TRAcP)-positive osteoclast cells and potentiation of apoptotic cancer cells, to a greater extent when combined than when the drugs were applied independently. Altogether, the combination treatment with PL and ZA could significantly and synergistically suppress osteoclastogenesis and inhibit tumorigenesis both in vitro and in vivo by simulating the spatial structure of ANP to inhibit competitively phosphorylation of c-Jun N-terminal kinase/extracellular signal-regulated kinase (JNK/Erk).

Hypereosinophilic obliterative bronchiolitis with an elevated level of serum CEA: a case report and a review of the literature.

A 44-year-old man presented with chronic, persistent cough and occasional wheezing. Airflow obstruction, blood eosinophilia and a remarkable elevated level of serum carcinoembryonic antigen (CEA) were found. Radiographic and pathological studies confirmed eosinophilic bronchiolitis. There was no evidence of neoplasms by extensive examinations. After a protracted oral steroid therapy, the blood eosinophil count, the serum CEA level and the lung lesions were all improved in parallel, whereas fixed airflow obstruction remained. This case was diagnosed as a new distinct syndrome, hypereosinophilic obliterative bronchiolits. Serum CEA and blood eosinophil cell count served as good markers of the disease condition for this syndrome.

OA-4 inhibits osteoclast formation and bone resorption via suppressing RANKL induced P38 signaling pathway.

Osteoclasts are one of the key therapeutic targets for a variety of orthopedic diseases such as osteoporosis and osteoarthritis. In this study, we synthesized a novel compound N-(3-(cyclohexylcarbamoyl) phenyl)-1H-indole-2- carboxamide (termed as OA-4) and investigated the effects of OA-4 on the differentiation and function of osteoclasts. OA-4 markedly diminished osteoclast differentiation and osteoclast specific gene expression in a dose-dependent manner. In addition, OA-4 dose-dependently suppressed osteoclastic bone resorption. Furthermore, we found OA-4 attenuated RANKL-induced p38 phosphorylation without affecting JNK or NF-κB signaling pathways. Collectively, we synthesized a novel compound OA-4 which can inhibit osteoclast formation and functions via the suppression of p38 signaling pathway.

Andrographolide suppresses RANKL-induced osteoclastogenesis in vitro and prevents inflammatory bone loss in vivo.

BACKGROUND AND PURPOSE: Osteoclasts play a pivotal role in diseases such as osteoporosis, rheumatoid arthritis and tumour bone metastasis. Thus, searching for natural compounds that may suppress osteoclast formation and/or function is promising for the treatment of osteoclast-related diseases. Here, we examined changes in osteoclastogenesis and LPS-induced osteolysis in response to andrographolide (AP), a diterpenoid lactone isolated from the traditional Chinese and Indian medicinal plant Andrographis paniculata. EXPERIMENTAL APPROACH: Effects of AP on osteoclast differentiation and bone resorption were measured in vitro. Western blots and RT-PCR techniques were used to examine the underlying molecular mechanisms. The bone protective activity of AP in vivo was assessed in a mouse model of osteolysis. KEY RESULTS: AP concentration-dependently suppressed RANKL-mediated osteoclast differentiation and bone resorption in vitro and reduced the expression of osteoclast-specific markers, including tartrate-resistant acid phosphatase, calcitonin receptors and cathepsin K. Further molecular analysis revealed that AP impaired RANKL-induced NF-κB signalling by inhibiting the phosphorylation of TGF-ß-activated kinase 1, suppressing the phosphorylation and degradation of IκBα, and subsequently preventing the nuclear translocation of the NF-κB p65 subunit. AP also inhibited the ERK/MAPK signalling pathway without affecting p38 or JNK signalling. CONCLUSIONS AND IMPLICATIONS: AP suppressed RANKL-induced osteoclastogenesis through attenuating NF-κB and ERK/MAPK signalling pathways in vitro, thus preventing bone loss in vivo. These data indicated that AP is a promising natural compound for the treatment of osteoclast-related bone diseases.

Biocompatibility and membrane strength of C3H10T1/2 cell-loaded alginate-based microcapsules.

BACKGROUND: C3H10T1/2 cells, from a mouse embryonic fibroblast cell line, were used to investigate the improvement of alginate-based microencapsulated cells for cellular therapy. METHODS: Purified sodium alginate (PSA) and non-purified sodium alginate (SA) were used to prepare alginate-based microcapsules, and their biocompatibility and membrane strength were then compared for the purposes of analyzing the advantages of purifying SA. In addition, poly-l-lysine (PLL) was replaced by chitosan for alginate-chitosan microcapsule preparation. The process of optimization and chemical modification of alginate-chitosan microcapsules using polyethylene glycol was also reviewed. RESULTS: The results showed improved biocompatibility and membrane strength of PSA-based microcapsules. Under optimal conditions, mesenchymal stromal cell (MSC)-loaded alginate-chitosan microcapsules with good morphology could be obtained using PSA and chitosans of medium molecular weight (1.0-2.5 x 10(5)). A chitosan solution of 0.1% (w/v) and a reaction time of 7 min between alginate and chitosan were determined as optimal preparation parameters. DISCUSSION: It could be concluded that the chemical modification of alginate-based microcapsules can improve their biocompatibility.

Biologic effect and immunoisolating behavior of BMP-2 gene-transfected bone marrow-derived mesenchymal stem cells in APA microcapsules.

We investigated the encapsulation of BMP-2 gene-modified mesenchymal stem cells (MSCs) in alginate-poly-L-lysine (APA) microcapsules for the persistent delivery of bone morphogenic protein-2 (BMP-2) to induce bone formation. An electrostatic droplet generator was employed to produce APA microcapsules containing encapsulated beta-gal or BMP-2 gene-transfected bone marrow-derived MSCs. We found that X-gal staining was still positive 28 days after encapsulation. Encapsulated BMP-2 gene-transfected cells were capable of constitutive delivery of BMP-2 proteins for at least 30 days. The encapsulated BMP-2 gene-transfected MSCs or the encapsulated non-gene transfer MSCs (control group) were cocultured with the undifferentiated MSCs. The gene products from the encapsulated BMP-2 cells could induce the undifferentiated MSCs to become osteoblasts that had higher alkaline phosphatase (ALP) activity than those in the control group (p<0.05). The APA microcapsules could inhibit the permeation of fluorescein isothiocyanate-conjuncted immunoglobulin G. Mixed lymphocyte reaction also indicates that the APA microcapsules could prevent the encapsulated BMP-2 gene-transfected MSCs from initiating the cellular immune response. These results demonstrated that the nonautologous BMP-2 gene-transfected stem cells are of potential utility for enhancement of bone repair and bone regeneration in vivo.

Treatment of osteonecrosis of the femoral head with hBMP-2-gene-modified tissue-engineered bone in goats.

The efficacy of beta-tricalcium phosphate (beta-TCP) loaded with bone morphogenetic protein-2 (BMP-2)-gene-modified bone-marrow mesenchymal stem cells (BMSCs) was evaluated for the repair of experimentally-induced osteonecrosis of the femoral head in goats. Bilateral early-stage osteonecrosis was induced in adult goats three weeks after ligation of the lateral and medial circumflex arteries and delivery of liquid nitrogen into the femoral head. After core decompression, porous beta-TCP loaded with BMP-2 gene- or beta-galactosidase (gal)-gene-transduced BMSCs was implanted into the left and right femoral heads, respectively. At 16 weeks after implantation, there was collapse of the femoral head in the untreated group but not in the BMP-2 or beta-gal groups. The femoral heads in the BMP-2 group had a normal density and surface, while those in the beta-gal group presented with a low density and an irregular surface. Histologically, new bone and fibrous tissue were formed in the macropores of the beta-TCP. Sixteen weeks after implantation, lamellar bone had formed in the BMP-2 group, but there were some empty cavities and residual fibrous tissue in the beta-gal group. The new bone volume in the BMP-2 group was significantly higher than that in the beta-gal group. The maximum compressive strength and Young's modulus of the repaired tissue in the BMP-2 group were similar to those of normal bone and significantly higher than those in the beta-gal group. Our findings indicate that porous beta-TCP loaded with BMP-2-gene-transduced BMSCs are capable of repairing early-stage, experimentally-induced osteonecrosis of the femoral head and of restoring its mechanical function.

BMP2 gene therapy on the repair of bone defects of aged rats.

Age-related decline in the number of mesenchymal stem cells (MSCs) and their reduced capability to differentiate osteogenically, along with diminished availability of growth factors, may be major factors accounting for reduced bone formation in the aging mammalian body. In the first part of the study, we compared the number of MSCs in bone marrow (BM) and the content of bone morphogenetic protein 2 (BMP2) in cortical bone tissue in juvenile, adult, and aged (1, 9, and 24 months, respectively) male rats. To assay the influence of aging on osteogenic differentiation ability, MSCs from the three age groups were transduced with the BMP2 gene. Following gene transduction, the production of BMP2 in culture media, expression of osteogenic proteins (e.g., alkaline phosphatase, type Ialpha1 collagen, osteopontin, and bone sialoprotein), as well as ectopic bone formation in athymic mice were compared. Results showed that the number of MSCs in BM as well as the content of BMP2 in cortical bone tissue decreased with age, but no significant differences between the three age groups were found with regard to production of BMP2 or capability of BMP2 gene-modified MSCs to differentiate osteogenically. The second part of the study applied BMP2 gene-modified autologous MSCs/beta-tricalcium phosphate for repair of bone defects in aged rats with positive results. Our data indicate that the osteogenic potential of MSCs of aged rats can be restored following BMP2 gene transduction and that this technique may be a useful approach in the future planning of gene therapy for age-related osteoporotic fractures.

Repairing of goat tibial bone defects with BMP-2 gene-modified tissue-engineered bone.

Bone defects larger than a critical size are major challenges in orthopedic medicine. We combined tissue-engineered bone and gene therapy to provide osteoprogenitor cells, osteoinductive factors, and osteo-conductive carrier for ideal bone regeneration in critical-sized bone defects. Goat diaphyseal bone defects were repaired with tissue and genetically engineered bone implants, composed of biphasic calcined bone (BCB) and autologous bone marrow derived mesenchymal stem cells (BMSC) transduced with human bone morphogenetic protein-2 (hBMP-2). Twenty six goats with tibial bone defects were divided into groups receiving implants by using a combination of BCB and BMSCs with or without the hBMP-2 gene. In eight goats that were treated with BCB that contained hBMP-2 transduced BMSC, five had complete healing and three showed partial healing. Goats in other experimental groups had only slight or no healing. Furthermore, the area and biochemical strength of the callus in the bone defects were significantly better in animals treated with genetically engineered implants. We concluded that the combination of genetic and tissue engineering provides an innovative way for treating critical-sized bone defects.

[The effect of stress-relaxation plate fixation on the remodeling of the cortex under plate].

OBJECTIVE: To explore the influence of stress-relaxation plate(SRP) fixation on the remodeling of cortex under plate. METHODS: Twenty-eight New Zealand rabbits were used in this study, the bilateral tibia were osteotomized in the middle and fixed with SRP (experimental group) and rigid plate (control group) respectively. The scanning electron microscopy was used to observe the bone remodeling process from 2 to 48 weeks after operation. RESULTS: There was cortex osteoporosis beneath plate in different degree in both experimental and control groups before 8 weeks, it showed as the disorganization of collagen fiber structure and formation of resorption cavities. In comparison, the osteoporosis degree in experimental group showed milder than that of the control group. After 12 weeks, the resorption cavities became smaller, and the structure of collagen fibers became regular with the alignment parallel to the long axis of cortex. In contrast to the experimental group, the bone osteoporosis under plate of control group exacerbated continuously. CONCLUSION: Without removal of the bone plate, SRP fixation not only reduce the degree of plated bone osteoporosis, but also make the osteoporosic bone return to normal.

[The gene expression of some cytokines and collagen proteins in rat bone tissue is related to estradiol (E2) and age].

30 female SD rats (3 months old) are equally divided into three groups: ovariectomy (OVX) rats, sham-operated (SHO) rats and 17 beta estradiol (E2) treated OVX rats. For each group, mRNA was isolated from long bone at one month and three months after surgery, respectively. mRNA was reverse transcribed into single strand cDNA and then used as a probe hybridizing to the DNA fragments of col I alpha(1), col I alpha(2), col III, col V, fibronectin, IL-1, IL-6, TGF-beta, LIF, TNF-alpha, TNF-beta by reverse northern and dot blot hybrization. The housekeeping gene, gapdh, was used as an internal control. The results show that in bone of rat, the stable expression of col I alpha (1), col I alpha(2) and col III are related to age not ovariectomy, while supplement with E2 can inhibit the expression of col III and col I alpha(2) completely. The expression of col V, IL-1, IL-6 can be inhibited by estrogen and recovered by removal of estrogen by OVX, then addition of E2 decreased it to the normal level. The expression of TGF-beta is also inhibited by estrogen. It increased during one month after overiectomy, and partially decreased in E2 complemented rat. Three months after surgery, the level of increasing and decreasing is less evident as two months ago. It seems that in young SD rat, the expression of TGF-beta is related to both estrogen and age.

Neonatal hypotonia and cardiomyopathy secondary to type IV glycogenosis.

A neonate with deficiency of branching enzyme (glycogenosis type IV) presented symptoms of severe hypotonia pre- and postnatally, and dilated cardiomyopathy in early infancy. The classical clinical manifestation of liver cirrhosis was not present, although amylopectin-like inclusions were found in the hepatocytes. In contrast to a previous report, the neurons in the brain stem and spinal anterior horns contained PAS-positive, diastase-resistant deposits. The combined involvement of the muscles and motor neurones could account for the severity of hypotonia. The muscle biopsy, electromyogram and biochemical and enzyme assays were helpful in establishing the diagnosis.

GM1-gangliosidosis type 1 involving the cutaneous vascular endothelial cells in a black infant with multiple ectopic Mongolian spots.

GM1-gangliosidosis (GM1) is one of the metabolic storage diseases, of which a differential diagnosis requires an array of biochemical assays to determine the enzyme deficiency. This approach is not only time-consuming and costly but also unavailable to most hospital laboratories. However, a presumptive diagnosis of GM1 may be made on the basis of coarse facial feature, foamy endothelial cells in the cutaneous blood vessels and ectopic Mongolian spots, if present. A more definitive diagnosis of GM1 is then made on the demonstration of deficiency of GM1 beta-galactosidase in leukocytes, plasma or cultured skin fibroblasts. Thus, a battery of enzyme tests may be averted.

Epithelioid hemangioendothelioma of the orbital bones.

PURPOSE: The authors report a case of an epithelioid hemangioendothelioma arising in the orbital bones. A review of the literature related to this rare orbital neoplasm identified eight well-documented cases, one of which occurred in a patient younger than that reported here, but none of which originated in bone. METHODS: A 3 1/2-month-old boy had a left inferior orbital mass that had grown rapidly over a 3-day period. An emergency computed tomography scan showed a large neoplasm with significant bone destruction of the zygoma and maxilla. Initial examination suggested a rhabdomyosarcoma, and a transconjunctival biopsy was performed, which was complicated by significant blood loss. The final pathologic diagnosis was an epithelioid hemangioendothelioma, or grade 2 hemangioendothelioma, of bone origin. No other sites of disease were found on metastatic survey. Subsequent treatment consisted of an en bloc tumor resection sparing the orbital soft tissues and globe. RESULTS: The patient is free of disease and has normal visual fixation and ocular motility 20 months after surgery. CONCLUSION: Epithelioid hemangioendothelioma, a vascular malignancy of endothelial cell origin, very rarely involves the orbit. This case is notable for its early development, rapid growth, bony origin, and epithelioid histology.