A case report on a novel use of intraoperative Intrabeam™ radiation therapy for a recurrent malignant peripheral nerve sheath tumor with sciatic nerve involvement.

Background: Malignant peripheral nerve sheath tumors (MPNST) are sarcomas that arise from peripheral nerves. They generally have a poor prognosis which is exacerbated by high local recurrence rates. This case report discusses the treatment of a patient with a MPNST with local recurrence.

Gamma Knife Radiosurgery for Arteriovenous Malformations Using a Four-Dimensional Dynamic Volume Computed Tomography Angiography Planning System as an Alternative to Traditional Catheter Angiogram.

Background Gamma knife radiosurgery (GKRS) remains a critical intervention in the long-term management of arteriovenous malformations (AVMs). For planning a treatment, identification of the nidus is essential, and it is dependent on high-resolution blood flow imaging, usually in the form of a traditional angiogram. The development of dynamic 320-slice computed tomography (CT) angiography has offered a noninvasive alternative to intra-arterial fluoroscopic imaging, and it is capable of providing equivalent temporal resolution.

A multispecialty pediatric neurovascular conference: a model for interdisciplinary management of complex disease.

Introduction: In 2013, our institution established a multidisciplinary pediatric neurovascular conference for coordination of care. Here, we review our initial experience.

Methods: Clinical and demographic data were obtained from medical records for patients presented to the pediatric neurovascular conference from April 2013 to July 2014.

Survival benefit for early hormone ablation in biochemically recurrent prostate cancer.

Purpose: To determine whether early initiation of androgen ablation in patients with biochemically recurrent prostate cancer, but without clinically evident metastases, is associated with improved overall or disease-specific survival. To describe subgroups, based on PSA kinetics, which are most likely to benefit from early androgen ablation.

Materials And Methods: A retrospective cohort of 124 patients, who were definitively treated by external beam radiotherapy between 1988 and 1999, and subsequently received androgen ablation for biochemical (92 patients) or clinically metastatic (32 patients) failure, was reviewed.

MammoSite and interstitial brachytherapy for accelerated partial breast irradiation: factors that affect toxicity and cosmesis.

Background: In interstitial brachytherapy (IB), cosmesis and toxicity correlate with volume of tissue irradiated, dose homogeneity index (DHI), and adjuvant doxorubicin/cyclophosphamide based chemotherapy (ACCT). MammoSite brachytherapy (MSB) irradiates smaller volumes than IB, and lower dose homogeneity does not appear to affect toxicity. However, clinical experience suggests that other factors may also play an important role in cosmesis and toxicity with MSB.

Interaction of a toxin from the scorpion Tityus serrulatus with a cloned K+ channel from squid (sqKv1A).

A toxin from the scorpion Tityus serrulatus (TsTX-Kalpha) blocks native squid K(+) channels and their cloned counterpart, sqKv1A, at pH 8 ((native)K(d) approximately 20 nM; (sqKv1A)K(d) approximately 10 nM). In both cases, decreasing the pH below 7.0 significantly diminishes the TsTX-Kalpha effect (pK = 6.

Structural and functional differences of two toxins from the scorpion Pandinus imperator.

The Pandinotoxins, PiTX-K alpha and PiTX-K beta, are members of the Charybdotoxin family of scorpion toxins that can be used to characterize K+ channels. PiTX-K alpha differs from PiTX-K beta, another peptide from Pandinus imperator, by one residue (P10E). When the two toxins are compared in a physiological assay, the affinity of PiTX-K beta for voltage-gated, rapidly inactivating K+ channels in dorsal root ganglia (DRG) neurons is 800-fold lower than that of PiTX-K alpha (K alpha-IC50 = 8.

Solution structure for Pandinus toxin K-alpha (PiTX-K alpha), a selective blocker of A-type potassium channels.

PiTX-K alpha, a 35-residue peptide recently isolated from the venom of Pandinus imperator, blocks the rapidly inactivating (A-type) K+ channel(s) in rat brain synaptosomes and the cloned Kv 1.2 potassium channel at very low toxin concentrations (6 nM and 32 pM, respectively) [Rogowski, R. S.

Three new toxins from the scorpion Pandinus imperator selectively block certain voltage-gated K+ channels.

Three 35-amino acid peptide K+ channel toxins (pandinotoxins) were purified from the venom of the scorpion Pandinus imperaton the toxins are designated pandinotoxin (PiTX)-K alpha, PiTX-K beta, and PiTX-K gamma. In an 86Rb tracer flux assay on rat brain synaptosomes, all three toxins selectively blocked the component of the K(+)-stimulated 86Rb efflux that corresponds to a voltage-gated, rapidly inactivating (A-type) K+ current (IC50 = 6, 42, and 100 nM, respectively). These toxins blocked neither the noninactivating component of the K(+)-stimulated 86Rb efflux (corresponding to a delayed rectifier) nor the Ca(2+)-dependent component of the 86Rb efflux (i.

Effect of disordered hemes on energy transfer rates between tryptophans and heme in myoglobin.

Our recent linear dichroism study of heme transitions (Gryczynski, Z., E. Bucci, and J.

Rates of energy transfer between tryptophans and hemes in hemoglobin, assuming that the heme is a planar oscillator.

Using the Förster equations we have estimated the rate of energy transfer from tryptophans to hemes in hemoglobin. Assuming an isotropic distribution of the transition moments of the heme in the plane of the porphyrin, we computed the orientation factors and the consequent transfer rates from the crystallographic coordinates of human oxy- and deoxy-hemoglobin. It appears that the orientation factors do not play a limiting role in regulating the energy transfer and that the rates are controlled almost exclusively by the intrasubunit separations between tryptophans and hemes.

Differences in myristic acid synthesis and in metabolic rate for P388 cells resistant to doxorubicin.

Lipids extracted from doxorubicin-resistant murine leukemia cells (P388/ADR) contained greater relative amounts of myristic and palmitoleic acids than lipids from sensitive cells (P388). This was seen in both the phospholipid and neutral lipid fractions under two nutritional conditions. Correspondingly in P388/ADR cells, myristic acid comprised a greater proportion of the products of the fatty acid synthetase system, and acyl-CoA 9-desaturase activity was transiently greater than in P388.

Cellular pharmacology of N,N',N''-triethylene thiophosphoramide.

N,N',N''-triethylene thiophosphoramide (Thio-TEPA) is an alkylating agent whose antineoplastic activity has been known for nearly 30 years. Human plasma pharmacokinetic studies revealed the presence of TEPA, a Thio-TEPA metabolite which after 4 h achieved plasma concentrations equal to those of the parent compound. We studied the activity of both Thio-TEPA and TEPA against murine leukemia P388 cells in culture.