A61603-induced contractions of the porcine meningeal artery are mediated by alpha1- and alpha2-adrenoceptors

It has recently been shown that A61603 (N-[5-(4,5-dihydro-1H-imidazol-2yl)-2-hydroxy-5,6,7,8-tetrahydro-naphthalen-1-yl]methane sulphonamide), a potent alpha(1A)-adrenoceptor agonist, decreased carotid artery conductance in anaesthetized pigs by a novel non-adrenergic mechanism. In this study, we set out to pharmacologically characterize A61603-induced contractions of the porcine isolated meningeal artery. While the maximum contractile responses of the artery were similar, A61603 (E(max): 183 +/- 23% of 100 mM KCl; pEC(50): 7.25 +/- 0.18) was more potent than noradrenaline (E(max): 156 +/- 16%; pEC(50): 5.75 +/- 0.17) or phenylephrine (E(max): 163 +/- 20%; pEC(50): 5.63 +/- 0.02). Prazosin (pA(2): 9.36 +/- 0.23) and, to a lesser extent, rauwolscine (pK(b): 6.36 +/- 0.38) and yohimbine (pK(b): 7.30 +/- 0.15) antagonised the contractions to A61603. The 5-HT(1B) (GR127935; N-[4-methoxy-3-(4-methyl-1-piperazinyl) phenyl]-2'-methyl-4'-(5-methyl-1,2,4-oxadiazol-3-yl)[1,1-biphenyl]-4-carboxamide) and 5-HT(2) (ritanserin) receptor antagonists failed to affect the responses to A61603, but methiothepin, which, in addition, has a high affinity for alpha-adrenoceptors, proved an effective antagonist. The A61603-induced responses were suppressed by the cAMP stimulator forskolin, but not by the protein kinase C inhibitor chelerythrine. Our results suggest that the contraction of porcine isolated meningeal artery by A61603 is mediated via mainly alpha(1)-(probably alpha(1A)) and, to a lesser extent, alpha(2)-adrenoceptors, involving the adenylyl cyclase, but not the diacylglycerol pathway.     

Radiotherapy of exudative age-related macular degeneration; a clinical and pathologic study

BACKGROUND: Radiotherapy has recently been employed to treat patients with exudative macular degeneration in order to prevent severe visual loss. Radiotherapy affects the evolution of exudative macular degeneration directly by endothelial toxicity, leading to capillary closure, and/or indirectly through its attenuating effects on the inflammatory response, mediated by macrophages and other inflammatory cells. METHODS: In this study we describe the histopathologic findings in a patient with exudative age-related macular degeneration (AMD) in both eyes whose right eye was treated with radiotherapy (5 times 2 Gy) 3 years before he died. The eyes were enucleated post mortem and investigated by light microscopy. Additionally, immunohistochemical investigation with antibodies against CD34 and CD68 was performed to identify patent endothelial cells and macrophages. RESULTS: Both eyes showed neovascular AMD consisting of mixed fibrocellular and fibrovascular membranes. Capillaries in both the choriocapillaris and the neovascular membrane were patent in both eyes. Macrophages were present in the choroidal neovascularization of both eyes. Neither preexistent choroidal, intraretinal, nor neovascular vessels showed increased wall thickness as sign of radiation damage. CONCLUSION: No radiation-related histopathologic effect could be demonstrated 3 years after radiation therapy in this patient with AMD.     

Youth tobacco sales in a metropolitan county: factors associated with compliance

OBJECTIVE: To describe and identify factors associated with tobacco sales in a metropolitan county. SETTING: King County, Washington is the largest county in Washington State with an estimated population of 1.8 million or about 30% of the state's population. DATA SOURCE: The data analysis is based on compliance checks in King County between January 2001 and March 2005. The 8879 checks were conducted by 91 youth operatives aged 14-17. Analysis of data was completed in 2006. STATISTICAL ANALYSIS: The outcome variable for this analysis was whether "a sale was made" to a youth operative during a compliance check. Associations between independent variables and the outcome variable were examined using 2 x 2 tables, univariate (unadjusted) logistic regression, and multivariate (adjusted) logistic regression analysis. RESULTS: Overall tobacco sales during the 4-year and 3-month period was 7.7%. Convenience stores selling gas were significantly more likely to sell tobacco products to minors, whereas restaurants, bars, and tobacco discount stores were less likely to sell to minors. Other factors that were significantly associated with sales are described. CONCLUSIONS: In a county that has adopted many of the required youth access laws, opportunities still exist to reduce sales of tobacco products to minors. Asking for age and photo identification still appears to be an effective strategy in reducing sales of tobacco products to minors.     

Studies of reservoir hosts for Marburg virus

To determine reservoir hosts for Marburg virus (MARV), we examined the fauna of a mine in northeastern Democratic Republic of the Congo. The mine was associated with a protracted outbreak of Marburg hemorrhagic fever during 1998-2000. We found MARV nucleic acid in 12 bats, comprising 3.0%-3.6% of 2 species of insectivorous bat and 1 species of fruit bat. We found antibody to the virus in the serum of 9.7% of 1 of the insectivorous species and in 20.5% of the fruit bat species, but attempts to isolate virus were unsuccessful.     

Final results of the double-blind placebo-controlled randomized phase 2 LOTUS trial of first-line ipatasertib plus paclitaxel for inoperable locally advanced/metastatic triple-negative breast cancer

Purpose

In LOTUS (NCT02162719), adding the oral AKT inhibitor ipatasertib to first-line paclitaxel for locally advanced/metastatic triple-negative breast cancer (aTNBC) improved progression-free survival (PFS; primary endpoint), with an enhanced effect in patients with PIK3CA/AKT1/PTEN-altered tumors (FoundationOne next-generation sequencing [NGS] assay). We report final overall survival (OS) results.

Methods

Eligible patients had measurable previously untreated aTNBC. Patients were stratified by prior (neo)adjuvant therapy, chemotherapy-free interval, and tumor immunohistochemistry PTEN status, and were randomized 1:1 to paclitaxel 80 mg/m² (days 1, 8, 15) plus ipatasertib 400 mg or placebo (days 1–21) every 28 days until disease progression or unacceptable toxicity. OS (intent-to-treat [ITT], immunohistochemistry PTEN-low, and PI3K/AKT pathway-activated [NGS PIK3CA/AKT1/PTEN-altered] populations) was a secondary endpoint.

Results

Median follow-up was 19.0 versus 16.0 months in the ipatasertib–paclitaxel versus placebo–paclitaxel arms, respectively. In the ITT population (n?=?124), median OS was numerically longer with ipatasertib–paclitaxel than placebo–paclitaxel (hazard ratio 0.80, 95% CI 0.50–1.28; median 25.8 vs 16.9 months, respectively; 1-year OS 83% vs 68%). Likewise, median OS favored ipatasertib–paclitaxel in the PTEN-low (n?=?48; 23.1 vs 15.8 months; hazard ratio 0.83) and PIK3CA/AKT1/PTEN-altered (n?=?42; 25.8 vs 22.1 months; hazard ratio 1.13) subgroups. The ipatasertib–paclitaxel safety profile was unchanged.

Conclusions

Final OS results show a numerical trend favoring ipatasertib–paclitaxel and median OS exceeding 2 years with ipatasertib–paclitaxel. Overall, results are consistent with the reported PFS benefit; interpretation within biomarker-defined subgroups is complicated by small sample sizes and TNBC heterogeneity.