Gene delivery to human adult and embryonic cell-derived stem cells using biodegradable nanoparticulate polymeric vectors.

Gene delivery to stem cells holds great potential for tissue regeneration and delivery of therapeutic proteins. The major barrier is the lack of safe and efficient delivery methods. Here, we report enhanced gene delivery systems for human stem cells using biodegradable polymeric vectors. A library of poly (beta-amino esters) end-modified derivatives was developed and optimized for high transfection efficiency and low cytotoxicity for three human stem cell lines including human mesenchymal stem cells (hMSCs), human adipose-derived stem cells (hADSCs) and human embryonic stem cell-derived cells (hESCds). In the presence of 10% serum, leading end-modified C32 polymeric vectors exhibited significantly high transfection efficiency in hMSCs (27+/-2%), hADSCs (24+/-3%) and hESCds (56+/-11%), with high cell viability (87-97%) achieved in all cell types. Our results show that poly(beta-amino esters) as a class, and end-modified versions of C32 in particular, are efficient polymeric vectors for gene delivery to both adult and embryonic-derived stem cells.

Clomiphene, an ovulation-inducing agent, causes [Ca2+]i increases in human osteoblast-like cells.

The effect of clomiphene, an ovulation-inducing agent, on cytosolic free Ca2+ levels ([Ca2+]i) in MG63 human osteosarcoma cells was explored by using fura-2 as a Ca2+ indicator. Clomiphene at concentrations between 5-75 microM increased [Ca2+]i in a concentration-dependent manner with an EC50 of 50 microM. The [Ca2+]i signal consisted of an initial rise and a sustained phase. Ca2+ removal reduced the Ca2+ signal by 40+/-10%. The [Ca2+]i increase induced by 50 microM clomiphene was inhibited by 80+/-5% by 10 microM nifedipine, but was insensitive to 50 microM La3+ or 10 microM verapamil. In Ca2+-free medium, pretreatment with 50 microM brefeldin A (to disrupt the Golgi complex Ca2+ store), 1 microM thapsigargin (to inhibit the endoplasmic reticulum Ca2+ pump), and carbonylcyanide m-chlorophenylhydrazone (CCCP; to uncouple mitochondria) inhibited 51+/-3% of 50 microM clomiphene-induced Ca2+ release; conversely, pretreatment with 50 microM clomiphene abolished the [Ca2+]i increase induced by thapsigargin, CCCP, and brefeldin A. The Ca2+ release-induced by 50 pM clomiphene was unchanged by inhibition of phospholipase C with 2 microM 1-(6-((17beta-3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione (U73122). Collectively, the results suggest that clomiphene increased [Ca2+]i, in osteoblast-like cells, by releasing intracellular Ca2+ in a phospholipase C-independent manner and by causing nifedipine-sensitive Ca2+ influx.

Maxillofacial prosthetic rehabilitation of a midfacial defect complicated by microstomia: a clinical report.

Severe limitation in the oral opening, though an uncommon clinical presentation, makes gaining access to the oral cavity difficult for any dental procedure. This article describes the maxillofacial prosthetic management of a patient with a midfacial defect complicated by postsurgical microstomia. Intraoral and extraoral prostheses restored the patient's speech, dental articulation, mastication, lip support, esthetics, and anterior oral seal.

Homozygous alpha-thalassemia associated with hypospadias in three survivors.

We report three cases of homozygous alpha-thalassemia (alphaTH) who survived beyond the neonatal period, all with hypospadias. A review of literature identified two additional male cases of homozygous alphaTH who survived, and both had hypospadias. The simultaneous occurrence of the two conditions seems beyond coincidence and may be causally related. Possible pathogenesis for the association may be 1) homozygous alphaTH-induced in utero and/or edema secondary to hydrops fetalis, both leading to the failure of proper fusion of the urogenital folds, or 2) defect of another gene located at a chromosome 16p13.3 region. Thus, parents who request intrauterine therapy for a male fetus with homozygous alphaTH should be informed about this association and its prognosis.

Evaluation of the hemostatic clot formation of newborns by Sonoclot coagulation analyzer.

BACKGROUND: Sonoclot Analyzer has been widely used for more than five years in The United States to evaluate the platelet function and coagulation in adult. No clinical trial with the Analyzer has been reported in the field of pediatrics. The present study was aimed to evaluate the efficacy of the Sonoclot Analyzer for urgent determination of platelet function and coagulation in newborns. METHODS: Venous blood samples were drawn from the umbilical vein in 70 healthy newborns, and from the median cubital vein in 70 healthy adult volunteers, between 24 to 40 years of age, for control. DP2951 Sonoclot II Surgical Analyzer with graphic printer was used to evaluate the hemostatic clot formation. RESULTS: Results demonstrated that Sono ACT (activated coagulation time), peak time and retraction time increased by 36%, 66% and 70% respectively in newborns, while clot rate decreased by 69% in comparison with that of these adults. CONCLUSIONS: The results of using the Sonoclot Analyzer in this study confirmed other previous investigation that platelet function and coagulation are altered in newborns when compared with that of adults. The Sonoclot Analyzer is a simple device, easy to perform; It requires only small amounts of blood sampled (0.4 ml), and provides a rapid coagulation function for newborns.