Our findings reveal altered perivascular inflammatory cell infiltration in pulmonary vascular lesions of patients with idiopathic pulmonary arterial hypertension. Targeting attraction of inflammatory cells by blocking stromal-derived factor-1 may be a novel approach for treatment of PAH.

Phosphodiesterases (PDEs) modulate the cellular proliferation involved in the pathophysiology of pulmonary hypertension (PH) by hydrolyzing cAMP and cGMP. The present study was designed to determine whether any of the recently identified PDEs (PDE7-PDE11) contribute to progressive pulmonary vascular remodeling in PH. All in vitro experiments were performed with lung tissue or pulmonary arterial smooth muscle cells (PASMCs) obtained from control rats or monocrotaline (MCT)-induced pulmonary hypertensive (MCT-PH) rats, and we examined the effects of the PDE10 inhibitor papaverine (Pap) and specific small interfering RNA (siRNA). In addition, papaverine was administrated to MCT-induced PH rats from day 21 to day 35 by continuous intravenous infusion to examine the in vivo effects of PDE10A inhibition. We found that PDE10A was predominantly present in the lung vasculature, and the mRNA, protein, and activity levels of PDE10A were all significantly increased in MCT PASMCs compared with control PASMCs. Papaverine and PDE10A siRNA induced an accumulation of intracellular cAMP, activated cAMP response element binding protein and attenuated PASMC proliferation. Intravenous infusion of papaverine in MCT-PH rats resulted in a 40%–50% attenuation of the effects on pulmonary hypertensive hemodynamic parameters and pulmonary vascular remodeling. The present study is the first to demonstrate a central role of PDE10A in progressive pulmonary vascular remodeling, and the results suggest a novel therapeutic approach for the treatment of PH.

We screened 50 glioblastomas for P53 mutations. Five glioblastomas showed heterozygous mutations, while three were putatively heterozygous. Six of these eight glioblastomas showed elimination of wild-type P53 mRNA. These results strongly suggest that some sort of mechanism(s) favouring mutated over wild-type P53 mRNA exists in glioblastoma cells with heterozygous mutations of this gene. (Nigro et al, 1989;Dittmer et al, 1993). However, the effects of at least some heterozygous mutations cannot be explained only by the gain of P53 function (Park et al, 1994). In case of P53 mutations such as R249S or R273H, at least three mutated monomers per tetramer appeared to be required to inactivate the transactivation of MDM2 and p21 CIP1/ WAF1 promoters (Chan et al, 2004). In case of R280T mutations, heterotetramers consisting even of three mutated and one wild-type P53 monomer showed partially but not completely abolished activity compared to P53 homotetramers consisting of wild-type monomers only (Sun et al, 1993). In this context, the occurrence of heterozygous mutations of P53 remains enigmatic, leading to a question of whether mechanisms other than P53 mutations or deletions are involved in the elimination of the wild-type P53 protein. Several nongenomic mechanisms of protein elimination or aberration have been described, including processes operating at the level of transcription (e.g., methylation) or translation (e.g., miRNA) (Voorhoeve et al, 2006;Watanabe et al, 2007). We examined whether glioblastoma cells with heterozygous mutations of P53 contained a mixture of wild-type and mutated P53 mRNA, or predominantly the mutated P53 mRNA. Additionally, we also checked the methylation status of the P53 promoter. MATERIALS AND METHODS Tumour samplesThe study included 50 cases of glioblastoma, diagnosed at Department of Pathology, Medical University of Lodz, according to the World Health Organization criteria for classification of brain tumours (Louis et al, 2007). The group consisted of 25 females and 25 males, aged from 15 to 76 years (median 59.5). DNA and RNA isolationThe investigations were performed using snap-frozen tissues stored at À801. DNA was isolated from tumour tissues and blood samples from each patient. DNA and RNA were coextracted by means of Macherey-Nagel DNA/RNA purification kit. RNA samples were treated with DNAase. RNA and DNA concentrations were measured spectrophotometrically. In all 100 ng of total RNA was reverse-transcribed into single-stranded cDNA in a final volume of 40 ml containing 50 mM DTT, 1.5 mg oligo(dT), 0.5 mM dNTP, 40 units RNase inhibitor and 200 units M-MLV reverse transcriptase (Promega). Loss of heterozygosity and microsatellite instability analysesLoss of heterozygosity (LOH) and microsatellite instability (MSI) analyses were performed using paired tumour specimens and corresponding peripheral blood samples, to recognise tumour samples with minimal contamination by normal cells. The following LOH and MSI markers were used:

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BackgroundThough insulin resistance (IR) is common in polycystic ovary syndrome (PCOS), there is no agreement as to what surrogate method of assessment of IR is most reliable.Subjects and methodsIn 478 women with PCOS, we compared methods based on fasting insulin and either fasting glucose (HOMA-IR and QUICKI) or triglycerides (McAuley Index) with IR indices derived from glucose and insulin during OGTT (Belfiore, Matsuda and Stumvoll indices).ResultsThere was a strong correlation between IR indices derived from fasting values HOMA-IR/QUICKI, r = −0.999, HOMA-IR/McAuley index, r = −0.849 and between all OGTT-derived IR indices (e.g. r = −0.876, for IRI/Matsuda, r = −0.808, for IRI/Stumvoll, and r = 0.947, for Matsuda/Stumvoll index, P < 0.001 for all), contrasting with a significant (P < 0.001), but highly variable correlation between IR indices derived from fasting vs OGTT-derived variables, ranging from r = −0.881 (HOMA-IR/Matsuda), through r = 0.58, or r = −0.58 (IRI/HOMA-IR, IRI/QUICKI, respectively) to r = 0.41 (QUICKI/Stumvoll), and r = 0.386 for QUICKI/Matsuda indices. Detailed comparison between HOMA-IR and IRI revealed that concordance between HOMA and IRI was poor for HOMA-IR/IRI values above 75th and 90th percentile. For instance, only 53% (70/132) women with HOMA-IR >75th percentile had IRI value also above 75th percentile. There was a significant, but weak correlation of all IR indices with testosterone concentrations.ConclusionsSignificant number of women with PCOS can be classified as being either insulin sensitive or insulin resistant depending on the method applied, as correlation between various IR indices is highly variable. Clinical application of surrogate indices for assessment of IR in PCOS must be therefore viewed with an extreme caution.