[4-dimensional computed tomography for localization of parathyroid adenoma].

INTRODUCTION: In about 85% of patients with primary hyperparathyroidism (pHPT) only a single parathyroid gland is diseased. The operation of choice in this group of patients is minimally invasive parathyroidectomy (MIP). In order to perform an MIP, the diseased gland should be identified prior to surgery. This is not always possible with the routine imaging studies including parathyroid sestamibi scan and ultrasound. Four-dimensional computed tomography (4D-CT) scanning was developed in order to identify an enlarged parathyroid gland. Several characteristics make it possible to identify glands of this type and to differentiate it from other neck nodes. PURPOSE: To evaLuate the accuracy of 4D-CT in the identification of parathyroid adenoma/s in order to perform an MIP. METHODS: A total of 69 patients underwent parathyroidectomy for pHPT during the period July 2010 to June 2012. The 4D-CT was performed on 27 patients. Data were retrospectively extracted from the patients' charts including imaging studies, operative notes, number and LocaLization of glands excised and pathological reports. RESULTS: The 4D-CT was positive for a single adenoma in 26 patients confirmed in surgery. In 4 of those patients, one or two additional glands were found enlarged during surgery. Sixteen patients underwent an MIP, 3 patients had a unilateraL exploration and in 8 cases a biLateraL exploration was performed. The 4D-CT had a sensitivity of 81.4% and a positive predictive value of 100% in this group of patients. CONCLUSIONS: The 4D-CT is another tool for the identification of enlarged parathyroid gLand/s before surgery. Further study is needed to determine its place in the current armamentarium of pre-operative localization studies.

Regulation of the action of early mitotic inhibitor 1 on the anaphase-promoting complex/cyclosome by cyclin-dependent kinases.

Cell cycle regulation is characterized by alternating activities of cyclin-dependent kinases (CDKs) and of the ubiquitin ligase anaphase promoting complex/cyclosome (APC/C). During S-phase APC/C is inhibited by early mitotic inhibitor 1 (Emi1) to allow the accumulation of cyclins A and B and to prevent re-replication. Emi1 is degraded at prophase by a Plk1-dependent pathway. Recent studies in which the degradation pathway of Emi1 was disrupted have shown that APC/C is activated at mitotic entry despite stabilization of Emi1. These results suggested the possibility of additional mechanisms other than degradation of Emi1, which release APC/C from inhibition by Emi1 upon entry into mitosis. In this study we report one such mechanism, by which the ability of Emi1 to inhibit APC/C is negatively regulated by CDKs. We show that in Plk1-inhibited cells Emi1 is stabilized and phosphorylated, that Emi1 is phosphorylated by CDKs in mitotic but not S-phase cell extracts, and that Emi1 phosphorylation by mitotic cell extracts or purified CDKs markedly reduces the ability of Emi1 to bind and to inhibit APC/C. Finally, we show that the addition of extracts from S-phase cells to extracts from mitotic cells protects Emi1 from CDK-mediated inactivation.

Smokeless consumption of medical cannabis pharmacokinetics, safety and feasibility of the CannaHALER© a phase 1a study.

BACKGROUND: Substantial advancements were achieved in the management of postoperative pain, however the need for further improvement remains. This study explores the pharmacokinetics and safety of the CannaHaler, a metered dose inhaler for plant material made by Kite-Systems situated in Tel-Aviv, Israel. METHODS: The study was conducted on 12 healthy adult volunteers divided into four arms (each arm/group holds 3 volunteers) with the evaporated plant material being Alaska strain provided by "Tikun Olam". This strain is a hybrid of 70% Sativa and 30% Indika strains, consisting of 20-22% THC and 0% CBD. Each arm received a single dose and groups were divided in an ascending dose fashion: Group I-IV receiving 10, 15, 20, 25 mg of THC respectively. The volunteers inhaled a single dose of THC using the CannaHaler, device. Blood samples for Δ9 - Tetrahydrocannabinol (THC) and 9-THCCOOH were taken at base line and up to 30 min after dosing. Adverse events were monitored following the inhalation. Pharmacokinetics profile was obtained for each patient in all arms. RESULTS: Ascending doses of THC produced a linear increase in the maximum concentration 10, 15, 20 and 25 mg of THC. (35.43 ± 5.97, 51.47 ± 13.79, 72.37 ± 15.93, 88.63 ± 14.75 respectively) with the same linear increase in the dimension of the AUC (441.59 ± 88.49, 624 ± 123.56, 698.35 ± 174.98, 971.36 ± 310.4 respectively) both with no change in the time needed to reach such concentration. No adverse events were recorded in all of study subjects. The CannaHaler achieved high Cmax (35.43-88.63 ng/mL) values and low coefficient of variations (16.64-26.79%) in comparison to both smoking and oral preparations, thus reaching the potential of a pharmaceutical grade device for inhaled substance. CONCLUSIONS: The current study showed that the use of Kite-Systems CannaHaler as a smokeless medical cannabis inhalation device is feasible and efficient. The low coefficient of variation together with the high Cmax values, suggest the potential use of the CannaHaler device as a pharmaceutical cannabis dosing administrator.

Regulation of APC/C (Cdh1) ubiquitin ligase in differentiation of human embryonic stem cells.

We have recently shown that Skp2 levels are high in undifferentiated human embryonic stem cells, but decline rapidly following induction of differentiation, thereby leading to accumulation of p27. Changes in Skp2 levels were found to be caused mainly by its rate of degradation. Here we show that the activity of APC/C (Cdh1), the ubiquitin ligase that targets Skp2 for degradation, increases markedly during the differentiation process of human embryonic stem cells. APC/C (Cdh1) is present but inactive in undifferentiated embryonic stem cells and becomes active in the differentiated state. The rise in APC/C (Cdh1) activity with differentiation appears to be due, at least in part, to a dramatic decline in the levels of its inhibitor Emi1. In addition, protein kinase activity also appears to contribute to the suppression of APC/C (Cdh1) activity in undifferentiated stem cells, possibly by inhibitory phosphorylation of Cdh1.

Differential effects of doxorubicin treatment on cell cycle arrest and Skp2 expression in breast cancer cells.

Overexpression of Skp2, the ubiquitin ligase subunit that targets p27 for degradation, is often observed in cancers, and is associated with aggressive tumor proliferation and poor prognosis. As there is no drug at present that specifically targets Skp2, studies were undertaken to examine the effects of commonly used drugs on Skp2 regulation. Doxorubicin is among the most effective antitumor agents used for the management of breast cancer, but its effect on Skp2 expression is unknown. The objective of this study was to examine the effect of doxorubicin on Skp2 expression regulation in breast cancer cell lines. The expression of Skp2 mRNA and the protein levels of Skp2, p27, p21 and cyclin B were examined in doxorubicin-treated MCF-7 and MDA-MB-231 breast cancer cells. The effect of doxorubicin on the cell cycle profile was assessed by fluorescence-activated cell sorting analysis. Doxorubicin decreased Skp2 mRNA and protein levels in MCF-7 cells, but had the opposite effect in MDA-MB-231 cells. p27 levels were slightly decreased, whereas p53 and p21 levels were significantly upregulated in doxorubicin-treated MCF-7 cells. In contrast, p27 levels were unaffected by doxorubicin treatment in MDA-MB-231 cells, but cyclin B levels were markedly increased. Doxorubicin arrested MCF-7 cells at G1/S and G2/M checkpoints, whereas MDA-MB-231 cells were arrested at G2/M only. The differential effects of doxorubicin on Skp2 expression in breast cancer cells depend upon the specific cell cycle checkpoints activated by the drug. These changes induced by doxorubicin, however, do not significantly affect p27 expression in these cell lines, suggesting that the potential of a given drug to alter p27 expression through Skp2 modulation might depend on its specific action on cell cycle arrest.