Preparation and in vitro characterization of chitosan nanoparticles containing Mesobuthus eupeus scorpion venom as an antigen delivery system

Hydrophilic nanoparticles have been widely investigated in recent years as delivery systems for therapeutic macromolecules such as antigens. In the present study Mesobuthus eupeus venom-loaded chitosan nanoparticles were prepared via ionic gelation of tripolyphosphate (TPP) and chitosan. The optimum encapsulation efficiency (91.1 percent) and loading capacity (76.3 percent) were obtained by a chitosan concentration of 2 mg/mL, chitosan-to-TPP mass ratio of 2 and M. eupeus venom concentration of 500 µg/mL. The average nanoparticle size at optimum conditions was determined by Zetasizer (Malvern Instruments, UK). The nanoparticle size was about 370 nm (polydispersity index: 0.429) while the zeta potential was positive. Transmission electron microscope (TEM) imaging showed a spherical, smooth and almost homogenous structure for nanoparticles. Fourier transform infrared (FTIR) spectroscopy confirmed tripolyphosphoric groups of TPP linked with ammonium groups of chitosan in the nanoparticles. The in vitro release of nanoparticles showed an initial burst release of approximately 60 percent in the first ten hours, followed by a slow and much reduced additional release for about 60 hours. It is suggested that the chitosan nanoparticles fabricated in our study may provide a suitable alternative to traditional adjuvant systems.(AU)

Intrasinus catheter-directed heparin infusion in the treatment of dural venous sinus thrombosis.

BACKGROUND AND PURPOSE: In this small series, local intrasinus catheter-directed heparin infusion with or without balloon thrombectomy was safe in the treatment of dural venous sinus thrombosis (DVST). Although systemic anticoagulation (SAC) is the treatment of choice, there is a lack of consensus regarding the best treatment should SAC fail or be contraindicated. We present our institutional experience with 16 patients in whom failure of, or contraindication to, SAC occurred and who subsequently underwent intrasinus catheter-directed heparin infusion with or without balloon thrombectomy. MATERIALS AND METHODS: A retrospective review of 16 patients ranging in age from 14 days to 77 years who had intrasinus catheter-directed heparin infusion was undertaken with 9 male and 7 female patients identified. Of these 16 patients, 4 (25%) had a contraindication to SAC and SAC failed in 12 (75%). Technically successful intrasinus infusion catheter placement was achieved in all 16 patients (100%). Mean duration of infusion was 3.3 days (range, 1-6 days). Adjunctive balloon thrombectomy was performed in 9 (56.3%) of 16 patients. No procedure-related mortality occurred. RESULTS: Partial and complete sinus recanalization occurred in 10 (62.5%) of 16 patients and 1 (6.3%) of 16 patients, respectively. There were 3 deaths (18.8%) attributed to disease progression. At most recent clinical follow-up (mean, 9.3 months), 11 (84.6%) of 13 surviving patients were independent, with a modified Rankin Scale (mRS) score of 1 or less. CONCLUSIONS: Local intrasinus catheter-directed heparin infusion with or without adjunctive balloon thrombectomy seems to be a safe and effective treatment of DVST in patients in whom SAC failed or in whom there was a contraindication to SAC. In addition, the risk for symptomatic intracranial hemorrhage may be significantly lower than intrasinus infusion of thrombolytics.

The use of the Olympus EndoArm for spinal and skull-based transsphenoidal neurosurgery.

Minimally invasive surgical techniques have evolved to reduce soft-tissue injury associated with open surgical techniques. The use of endoscopic visualization allows the exposure of deep structures and provides a mechanism to perform all the components of an open surgical procedure through small portals, thus satisfying a basic requirement of minimally invasive surgical procedures. Surgeons in the field of skull-base and spine surgery are now taking advantage of the benefits of such endoscopes. The pneumatically powered EndoArm endoscopic holder has been used extensively in both cranial and spinal neurosurgical cases at the University of Utah. These cases include minimally invasive cervical and lumbar decompression procedures, as well as more recently the resection of larger and more extensive pituitary tumors. In this paper, the multiple advantages of the Olympus EndoArm endoscopic holder are described in detail. As more surgeons gain experience with endoscopes in skull-base surgery, the hope is that operative times will be shorter and more extensive surgical resections will be possible with less patient morbidity.

Progressive multifocal leucoencephalopathy associated with lupus and methotrexate overdose.

Progressive multifocal leucoencephalopathy (PML) is a CNS infection of oligodendrocytes by JC virus, which rarely occurs in lupus, and can be mistaken for antiphospholipid antibody syndrome or neuropsychiatric systemic lupus erythematosus (NSLE). This case of PML in a patient with systemic lupus erythematosus on supra-therapeutic doses of methotrexate emphasises that CNS infection is an important diagnostic consideration before empiric treatment with immunosuppresants for NSLE.

The effect of maternal anemia and iron deficiency on fetal erythropoiesis: comparison between serum erythropoietin, hemoglobin and ferritin levels in mothers and newborns.

OBJECTIVE: Maternal and fetal serum erythropoietin levels were correlated with hemoglobin, mean corpuscular volume and serum ferritin in a group of anemic pregnant women to evaluate the effect of maternal anemia on fetal erythropoiesis. METHODS: Serum erythropoietin, ferritin, hemoglobin and mean corpuscular volume were investigated in 33 pregnant women with anemia, 11 women with normal hematological parameters and in their newborns. RESULTS: Maternal serum erythropoietin concentration (mean +/- SEM) was significantly higher in the anemic group (145.2 +/- 42.9 mU/ml) as compared to the control group (37.3 +/- 7.6 mU/ml) (p < 0.05). In newborns, all parameters were comparable in both groups except cord serum erythropoietin concentration (mean +/- SEM) which was significantly higher in newborns born to anemic women (43.9 +/- 5.3 mU/ml) than controls (29.4 +/- 3.7 mU/ml) (p < 0.05). In the anemic group, maternal serum erythropoietin was inversely correlated to maternal hemoglobin (r = -0.375, p = 0.03), maternal hemoglobin was inversely correlated to cord serum erythropoietin (r = -0.552, p = 0.001) and maternal ferritin was correlated to fetal ferritin (r = 0.521, p = 0.002). CONCLUSION: Although cord hemoglobin and mean corpuscular volume were not affected by maternal anemia, increased cord serum erythropoietin levels related to low maternal hemoglobin levels suggest an induced fetal erythropoiesis in maternal anemia.