Impairment of acetylcholine-mediated endothelium-dependent relaxation in isolated parotid artery of the alloxan-induced diabetic rabbit

The aim of this study was to assess the effect of type 1 diabetes mellitus (induced by a single intravenous injection of 100 mg kg(-1) of alloxan) on acetylcholine (ACh)-induced relaxation in isolated rabbit parotid gland feeding artery. Isometric force measurements and quantification of inducible nitric oxide synthase (iNOS) mRNA by real-time RT-PCR were made in parotid artery rings from diabetic and control rabbits. Acetylcholine induced concentration- and endothelium-dependent vasorelaxation that was significantly decreased in parotid artery rings from diabetic rabbits. Schild analysis of the ACh vasorelaxant effect, in the presence of selective muscarinic receptor antagonists, revealed involvement of the M(3) receptor subtype in parotid artery rings from both control and diabetic rabbits, with no change in antagonist affinity constants. The inhibitory effects of indomethacin, a non-selective inhibitor of cyclooxygenase, and of high potassium, an inhibitor of hyperpolarization, on ACh vasorelaxation were increased. The effect of N(G) -nitro-l-arginine, a non-selective inhibitor of NOS, was decreased in diabetes. S-methylisothiourea, a selective inhibitor of iNOS, significantly reduced ACh vasorelaxation only in parotid artery rings from diabetic rabbits. Also, up-regulation of iNOS mRNA expression was detected in parotid artery rings from diabetic rabbits. These results suggest that in parotid artery rings from diabetic rabbits, impaired endothelium-dependent vasorelaxation to ACh appears to be caused by the loss of a nitric oxide-mediated component and increased iNOS expression, and is unlikely to be caused by a change at the M(3) receptor level.     

Continental-Mediterranean and rural-urban differences in cardiovascular risk factors in Croatian population

Aim

To compare the distribution of cardiovascular disease (CVD) factors between continental and Mediterranean areas and urban and rural areas of Croatia, as well as to investigate the differences in achieving treatment goals by the general practitioners (GP) in different settings.

Methods

A multicenter prospective study was performed on 2467 participants of both sexes ≥40 years old, who visited for any reason 59 general practices covering the whole area of Croatia (May-July 2008). The study was a part of the Cardiovascular Risk and Intervention Study in Croatia-family medicine (CRISIC-fm) study. Patients were interviewed using a 140-item questionnaire on socio-demographics and CVD risk factors. We measured body mass index (BMI) and waist circumference and determined biochemical variables including blood pressure, total, high-density lipoprotein-, and low-density lipoprotein-cholesterol, triglycerides, glycemia, and uric acid.

Results

Participants from continental rural areas had significantly higher systolic and diastolic blood pressure (P < 0.001), obesity (P = 0.001), increased waist circumference (P < 0.001), and more intense physical activity (P = 0.020). Participants from coastal rural areas had higher HDL-cholesterol, participants from continental rural and coastal urban areas had higher LDL-cholesterol, and participants from rural continental had significantly higher BMI and waist circumference.

Conclusion

Prevalence of CVD risk factors in Croatian population is high. Greater burden of risk factors in continental region and rural areas may be partly explained by lifestyle differences.Cardiovascular disease (CVD) is the major cause of death in the developed world but also an increasingly important cause in developing and underdeveloped countries that are adopting the Western way of life (1). In Europe, there was an increase in CVD mortality from north to south, but recently an increase from west to east has been observed. Still, the lowest mortality rates are mainly found in the Mediterranean countries (2). Although Croatia is geographically a Mediterranean country, its CVD mortality rate is significantly higher than in other Mediterranean countries, and in fact it is closer to Central and Eastern Europe (Croatian paradox) (2,3). CVD is a leading cause of death in Croatia and contributes to nearly 50% of total mortality cases (4).Only a few epidemiological studies on CVD risk factors in general population of Croatia have been performed over the last 50 years. A study performed in 1995-1997 did not investigate anthropometric data on central obesity (5), while Croatian Adult Health Survey performed in 2003 did not include a laboratory analysis of important CVD risk factors (6).Although there was one prevalence study on hypertension in Croatian general population (7), two studies on risk factors on hospitalized patients with CVD (8,9), and one small survey on high risk persons as a part of a large multinational study (10), there has been no comprehensive study of the CVD risk factors and total CVD risk in a representative sample of the adult general population in Croatia. There was also only one study comparing CVD risk factors in different regions of Croatia but it was performed on hospitalized patients with CVD eight years ago (11).The aim of our study was to investigate the distribution and possible differences among CVD risk factors (elevated blood pressure, dyslipidemia, hyperglycemia, hyperuricemia, smoking, overweight, obesity and central obesity, physical activity, alcohol consumption, total CVD risk calculated by SCORE and by Framingham) between different parts of Croatia (continental-inland and Mediterranean-coastal) and different settlement sizes (urban/rural), as well as to determine whether the target values of CVD risk factors (blood pressure, serum lipids, blood glucose) according to the guidelines (12) are achieved in the primary and secondary CVD prevention.     

Reversal of FLT3 mutational status and sustained expression of NPM1 mutation in paired presentation, and relapse samples in a patient with acute myeloid leukemia

We report a case of de novo acute myeloid leukemia (AML) with unstable FLT3 gene mutations and stable NPM1 mutation. FLT3/D835 and NPM1 (Type A) mutations were detected upon diagnosis. During the relapse, the FLT3/D835 mutation changed to an FLT3/ITD mutation while the NPM1 (Type A) mutation was retained. Cytogenetic analyses showed the normal karyotype at diagnosis and relapse. Our findings raise interesting questions about the significance of these mutations in the leukemogenic process, about their stability during the evolution of the disease, and regarding the selection of appropriate molecular markers for the monitoring of minimal residual disease.     

C-myc as a predictive marker for chemotherapy in metastatic breast cancer

C-myc is considered to have an important role in cancerogenesis and tumor progression. The aim of this study was to evaluate a possible significance of c-myc amplification as a clinically useful prognostic/predictive parameter in metastatic breast cancer (MBC). Eighty-seven MBC patients with known clinicopathological parameters were included in the study, at the time of diagnosis of metastatic disease. In metastatic setting, 52% of patients received CMF, 34% received FAC, and 32% received hormonal therapy (tamoxifen). C-myc amplification was analyzed by chromogenic in situ hybridization, according to the manufacturer's instructions. C-myc amplification was detected in 26% cases and showed a strong correlation with ER status, stage of disease (initial) and existence of distance metastasis. There was no statistically significant difference in MBC (post-relapse) survival between c-myc-nonamplified and c-myc-amplified subgroups regardless of or regarding the treatment. However, correlation was found between c-myc status and individual patient's outcomes. Patients with c-myc amplification treated with chemotherapy (CMF and FAC) had clinical benefit (complete remission, partial remission or stable disease) in contrast to patients without amplification. Lack of significant difference in MBC (post-relapse) survival according to c-myc status could be due to a better response of patients to appropriate treatment (chemotherapy). It is possible that negative prognostic impact of c-myc amplification is masked with increased responsiveness to chemotherapy.     

Alpha-1-antitrypsin Phenotypes and Neutrophil Elastase Gene Promoter Polymorphisms in Lung Cancer

Imbalance between neutrophil elastase and alpha-1-antitrypsin (AAT) leads to emphysema in smokers as well as in patients with inherited alpha-1-antitrypsin deficiency. AAT as a proven inhibitor of apoptosis may play role in lung cancer (LC) progression. The aim was to analyse AAT protein variants and polymorphism in promoter region of the neutrophil elastase gene (ELA2) in patients with primary lung cancer. AAT phenotypisation by isoelectric focusing method and ELA2 gene promoter characterization by DNA sequencing were performed in 66 patients with primary lung cancer. Results showed that the frequency of M1 allele and PiM1 homozygotes in LC patients was significantly higher when compared to the healthy subjects (f = 0.6360 and 0.7424 respectively). The most frequent ELA2 promoter region genotypes in LC patients were −903TT and −741GG. There were significantly more patients with intermediate and high ELA2 genotype activity, compared to those with low activity (91% vs. 9%, respectively). In conclusion, we found that PiM1 homozygosity could be associated with the lung cancer, probably due to increased synthesis of this antiapoptotic protein. Non-MM variants of AAT and ELA2 genotypes with predicted intermediate or high activity could also represent a risk factor for aggressive form of lung cancer associated with extrathoracic metastases.     

A1ATVar: a relational database of human SERPINA1 gene variants leading to α1‐antitrypsin deficiency and application of the VariVis software

We have developed a relational database of human SERPINA1 gene mutations, leading to α₁‐antitrypsin (AAT) deficiency, called A₁ATVar, which can be accessed over the World Wide Web at www.goldenhelix.org/A1ATVar . Extensive information has been extracted from the literature and converted into a searchable database, including genotype information, clinical phenotype, allelic frequencies for the commonest AAT variant alleles, methods of detection, and references. Mutation summaries are automatically displayed and user‐generated queries can be formulated based on fields in the database. A separate module, linked to the FINDbase database for frequencies of inherited disorders allows the user to access allele frequency information for the three most frequent AAT alleles, namely PiM, PiS, and PiZ. The available experimental protocols to detect AAT variant alleles at the protein and DNA levels have been archived in a searchable format. A visualization tool, called VariVis, has been implemented to combine A₁ATVar variant information with SERPINA1 sequence and annotation data. A direct data submission tool allows registered users to submit data on novel AAT variant alleles as well as experimental protocols to explore SERPINA1 genetic heterogeneity, via a password‐protected interface. Database access is free of charge and there are no registration requirements for querying the data. The A₁ATVar database is the only integrated database on the Internet offering summarized information on AAT allelic variants and could be useful not only for clinical diagnosis and research on AAT deficiency and the SERPINA1 gene, but could also serve as an example for an all‐in‐one solution for locus‐specific database (LSDB) development and curation. Hum Mutat 0,1–6, 2008. © 2008 Wiley‐Liss, Inc.     

Masked Hypertension and Left Atrial Dysfunction: A Hidden Association

Masked hypertension (MH) is a clinical condition that indicates normal values of clinic blood pressure (BP) but elevated 24‐hour BP. The purpose of this study was to investigate the relationship between MH and left atrial (LA) phasic function evaluated by both the volumetric and speckle tracking method. This cross‐sectional study included 49 normotensive individuals, 50 patients with MH, and 70 untreated sustained hypertensive patients adjusted by age and sex. MH was diagnosed if clinic BP was normal and 24‐hour BP was increased. LA reservoir function was lower in patients with MH and those with sustained hypertension compared with the normotensive group. LA conduit function gradually decreased, while LA booster pump function progressively increased, from normotension to sustained hypertension. Similar results were obtained by two‐dimensional echocardiographic strain analysis. Independently of main clinic and echocardiographic characteristics, 24‐hour systolic BP was associated with LA passive ejection fraction, LA total longitudinal strain, LA positive longitudinal strain, and LA stiffness index. In conclusion, MH is associated with impairment of LA phasic function and stiffness, and 24‐hour systolic BP increment was closely related with LA remodeling.     

Psychopharmacotherapy of posttraumatic stress disorder

Posttraumatic stress disorder (PTSD) is a psychiatric disorder that develops after a psychological trauma usually caused by a situation perceived as deeply threatening to a person’s life or integrity. Complex neurobiological changes triggered by such a traumatic and stressful experience may explain a wide range of PTSD symptoms and provide the rationale for psychopharmacological treatment. Selective serotonin-reuptake inhibitors make the first-line treatment of PTSD. Clinical experience has shown that they are more effective than noradrenalin-reuptake inhibitors or tricyclic antidepressants. Antipsychotic drugs, especially atypical ones, have been shown effective in PTSD patients with psychotic characteristics or refractoriness to other treatments. Mood stabilizers seem to reduce mostly autonomous overreactions to stress, whereas the evidence for effectiveness of monoamine oxidase inhibitors is largely inconclusive. Other groups of medications, such as serotonin agonists and antagonists, new antidepressants, dual inhibitors of serotonin- and noradrenalin-reuptake, anticonvulsants, and opiate antagonists are also sometimes used in PTSD treatment. However, as shown in the present review, most clinical studies performed to date to investigate the effectiveness of different psychopharmacological agents in the therapy of PTSD have serious limitations in terms of small sample size, lack of blinding and randomization, and small effect size. More rigorously designed, comparative studies are needed to determine the usefulness, efficacy, tolerability, and safety of particular psychopharmaceutical drugs in the treatment of this therapeutically and functionally challenging disorder.