Trigeminocardiac reflex by mandibular extension on rat pial microcirculation: Role of nitric oxide

In the present study we have extended our previous findings about the effects of 10 minutes of passive mandibular extension in anesthetized Wistar rats. By prolonging the observation time to 3 hours, we showed that 10 minutes mandibular extension caused a significant reduction of the mean arterial blood pressure and heart rate respect to baseline values, which persisted up to 160 minutes after mandibular extension. These effects were accompanied by a characteristic biphasic response of pial arterioles: during mandibular extension, pial arterioles constricted and after mandibular extension dilated for the whole observation period. Interestingly, the administration of the opioid receptor antagonist naloxone abolished the vasoconstriction observed during mandibular extension, while the administration of Nω-Nitro-L-arginine methyl ester, a nitric oxide synthase inhibitor, abolished the vasodilation observed after mandibular extension. Either drug did not affect the reduction of mean arterial blood pressure and heart rate induced by mandibular extension. By qRT-PCR, we also showed that neuronal nitric oxide synthase gene expression was significantly increased compared with baseline conditions during and after mandibular extension and endothelial nitric oxide synthase gene expression markedly increased at 2 hours after mandibular extension. Finally, western blotting detected a significant increase in neuronal and endothelial nitric oxide synthase protein expression. In conclusion mandibular extension caused complex effects on pial microcirculation involving opioid receptor activation and nitric oxide release by both neurons and endothelial vascular cells at different times

Effects of bone marrow mesenchymal stem cells (BM-MSCs) on rat pial microvascular remodeling after transient middle cerebral artery occlusion

Previous studies have shown that the pial microcirculation remodeling improves neurological outcome after middle cerebral artery occlusion (MCAO), accompanied by higher expression of vascular endothelial growth factor (VEGF) and endothelial nitric oxide synthase (eNOS), modulating in vivo angiogenesis. This study was aimed to assess the effects of bone marrow mesenchymal stem cells (BM-MSCs) infused after MCAO on rat pial microcirculation. Animals were subjected to 2 h MCAO followed by BM-MSCs infusion into internal carotid artery. Pial microcirculation was observed at different reperfusion times by fluorescence microscopy. Geometric characteristics of arteriolar networks, permeability increase, leukocyte adhesion, perfused capillary density, VEGF, and endothelial nitric oxide synthase (e-NOS) expression were evaluated. Green fluorescent protein (GFP)-BM-MSCs were used to evaluate their distribution and cell phenotype development during reperfusion. BM-MSCs stimulated a geometric rearrangement of pial networks with formation of new anastomotic vessels sprouting from preexistent arterioles in the penumbra at 7-14-28 days of reperfusion. At the same time VEGF and eNOS expression increased. GFP-BM-MSCs appear to be involved in endothelial and smooth muscle cell programming in the infarcted area. In conclusion, transient MCAO induced pial vascular remodeling characterized by arteriolar anastomotic arcades (originated from preexistent arterioles in penumbra area) able to overlap the ischemic core supplying blood to the neuronal tissue. BM-MSCs appear to accelerate angiogenic processes facilitating new vessel formation; this mechanism was promoted by an increase in VEGF and eNOS expression

The cAMP-HMGA1-RBP4 system: a novel biochemical pathway for modulating glucose homeostasis

<p>Abstract</p> <p>Background</p> <p>We previously showed that mice lacking the high mobility group A1 gene (<it>Hmga1</it>-knockout mice) developed a type 2-like diabetic phenotype, in which cell-surface insulin receptors were dramatically reduced (below 10% of those in the controls) in the major targets of insulin action, and glucose intolerance was associated with increased peripheral insulin sensitivity. This particular phenotype supports the existence of compensatory mechanisms of insulin resistance that promote glucose uptake and disposal in peripheral tissues by either insulin-dependent or insulin-independent mechanisms. We explored the role of these mechanisms in the regulation of glucose homeostasis by studying the <it>Hmga1</it>-knockout mouse model. Also, the hypothesis that increased insulin sensitivity in <it>Hmga1</it>-deficient mice could be related to the deficit of an insulin resistance factor is discussed.</p> <p>Results</p> <p>We first show that HMGA1 is needed for basal and cAMP-induced retinol-binding protein 4 (<it>RBP4</it>) gene and protein expression in living cells of both human and mouse origin. Then, by employing the <it>Hmga1</it>-knockout mouse model, we provide evidence for the identification of a novel biochemical pathway involving HMGA1 and the RBP4, whose activation by the cAMP-signaling pathway may play an essential role for maintaining glucose metabolism homeostasis <it>in vivo</it>, in certain adverse metabolic conditions in which insulin action is precluded. In comparative studies of normal and mutant mice, glucagon administration caused a considerable upregulation of HMGA1 and RBP4 expression both at the mRNA and protein level in wild-type animals. Conversely, in <it>Hmga1</it>-knockout mice, basal and glucagon-mediated expression of RBP4 was severely attenuated and correlated inversely with increased <it>Glut4 </it>mRNA and protein abundance in skeletal muscle and fat, in which the activation state of the protein kinase Akt, an important downstream mediator of the metabolic effects of insulin on Glut4 translocation and carbohydrate metabolism, was simultaneously increased.</p> <p>Conclusion</p> <p>These results indicate that HMGA1 is an important modulator of <it>RBP4 </it>gene expression <it>in vivo</it>. Further, they provide evidence for the identification of a novel biochemical pathway involving the cAMP-HMGA1-RBP4 system, whose activation may play a role in glucose homeostasis in both rodents and humans. Elucidating these mechanisms has importance for both fundamental biology and therapeutic implications.</p

Effects of physical exercise associated with a diet enriched with natural antioxidants on cerebral hypoperfusion and reperfusion injury in spontaneously hypertensive rats

Oxidative stress is implicated in the pathogenesis of arterial hypertension. The reduction in the bioavailability of nitric oxide (NO) causes endothelial dysfunction, altering the functions of cerebral blood vessels. Physical exercise and intake of antioxidants improve the redox state, increasing the vascular NO production and/or the decrease in NO scavenging by reactive oxygen species (ROS). The present study was aimed at assessing the effects of physical exercise associated with a diet enriched with antioxidants from the Annurca apple in preventing the microvascular damage due to cerebral hypoperfusion and reperfusion injury in spontaneously hypertensive rats (SHRs). The rat pial microcirculation was investigated by intravital fluorescence microscopy through a parietal closed cranial window. As expected, SHRs subjected to physical exercise or an antioxidants-enriched diet showed a reduction of microvascular permeability, ROS formation, and leukocyte adhesion to venular walls, with a major effect of the antioxidants-enriched diet, when compared to untreated SHRs. Moreover, capillary perfusion was preserved by both treatments in comparison with untreated SHRs. Unexpectedly, the combined treatments did not induce higher effects than the single treatment. In conclusion, our results support the efficacy of physical activity or antioxidant supplement in reducing the microvascular alterations due to hypertension and ascribe to an antioxidants-enriched diet effective microvascular protection in SHRs

BRCA1 and BRCA2 mutations in central and southern Italian patients

INTRODUCTION: Germline BRCA1 and BRCA2 mutations account for most hereditary breast/ovarian cancers and are associated with male breast cancer. Furthermore, constitutional mutations in these genes may occur in breast/ovarian cancer patients that do not meet stringent criteria of autosomal-dominant predisposition. The relevance of BRCA1 and BRCA2 mutations in such patients is still debated. OBJECTIVES: We sought to determine the impact of BRCA1 and BRCA2 mutations in a population of patients from central and southern Italy. We analyzed the BRCA1 and BRCA2 coding regions in 136 unrelated probands: 117 females with breast/ovarian cancer and 19 males with breast cancer. This population of patients was mostly representative of cases who are at risk for hereditary susceptibility, but who do not meet stringent criteria of autosomal-dominant predisposition. METHODS: Probands, subclassified as follows, were consecutively recruited depending on informed consent from patients attending breast cancer clinics in Rome and Naples. Selection criteria for females were as follows: breast cancer with breast cancer family history [one to two first-/second-degree relative(s), n = 55]; breast cancer diagnosed before age 40 years (no breast/ovarian cancer family history, n = 28); bilateral breast cancer (regardless of age and family history, n =10); breast cancer associated with gastrointestinal, pancreatic or uterine cancers [synchronous/metachronous or in first-degree relative(s), n = 9]; breast or ovarian cancer with family history of breast-ovarian/ovarian cancer (at least 1 first-/ second-degree relative, n = 10); and ovarian cancer with no breast/ovarian cancer family history (n = 5). Males with breast cancer were recruited regardless of age and family history. BRCA1 exon 11 and BRCA2 exons 10 and 11 were screened by PTT. Coding BRCA1 exons 2, 3, 5-10 and 12-24 and BRCA2 exons 2-9 and 12-27 were screened by SSCP. Primers are listed in Table 1. In 27 cases, analyzed by PTT along the entire BRCA1 coding sequence, BRCA1 SSCP analysis was limited to exons 2, 5, 20 and 24. Mutations were verified by sequence analysis on two independent blood samples. RESULTS: Deleterious germline BRCA1/BRCA2 mutations were detected in 11 out of 136 cases (8%). Only three BRCA2 mutations were novel. One BRCA2 mutation recurred in two unrelated probands. Table 2 shows the mutations and data concerning carriers and their families. Table 3 shows correlations between BRCA1/BRCA2 mutations and sex, age at disease diagnosis and familial clustering of breast/ovarian cancer in the total patient population. Table 4 shows the proportions of BRCA1 and BRCA2 mutations in females with site-specific breast and breast-ovarian/ovarian cancer. Table 5 shows the frequency of BRCA1/BRCA2 mutations in males. BRCA1 and BRCA2 mutations, respectively, accounted for four out of 68 (6%) and one out of 68 (1%) cases diagnosed before age 50 years, and for one out of 68 (1%) and five out of 68 (7%) cases diagnosed after age 50 years. BRCA1 mutations were found in five out of 117 females (4%) and in none of 19 males (0%), and BRCA2 mutations were found in four out of 117 females (3%) and in two out of 19 males (10%). The proportions of BRCA1 and BRCA2 mutations coincided in site-specific female breast cancers (four out of 102; ie 4% each). BRCA1 and BRCA2 equally contributed to female breast cancers, with no familial clustering in those diagnosed before age 40 years (one out of 28; 4% each), and to female breast cancers, all ages, with familial clustering in one to two relatives (three out of 55; ie 5% each). In the latter subset of cases, BRCA1 mostly accounted for tumours diagnosed before age 40 years (two out of eight; 25%), and BRCA2 for tumours diagnosed after age 50 years (three out of 34; 9%). Regardless of family history, the respective contributions of BRCA1 and BRCA2 to site-specific female breast cancers diagnosed before age 40 years were 8% (three out of 36) and 3% (one out of 36). One BRCA1 mutation was detected among the 15 female probands from breast-ovarian/ovarian cancer families (7%). Among male breast cancers, BRCA2 mutations were identified in one out of five (20%) cases with family history and in one out of 14 (7%) apparently sporadic cases. No BRCA1 or BRCA2 mutations were found in female probands with nonfamilial bilateral breast cancer (10 cases) or in those with breast cancer associated with gastrointestinal, pancreatic or uterine cancers, synchronous/metachronous or in first-degree relative(s) (nine cases). These cases were all diagnosed after age 40 years. DISCUSSION: Our results indicate a lack of relevant founder effects for BRCA1- and BRCA2-related disease in the sample of patients studied, which is consistent with other Italian studies and with ethnical and historical data. Overall, the contribution of BRCA1 and BRCA2 to breast/ovarian cancer in Italian patients appears to be less significant than in patients from communities with founder mutations. The present study is in agreement with direct estimates on other outbred populations, indicating that 7-10% of all female breast cancers that occur in patients aged under 40 years are due to BRCA1/BRCA2. We found that BRCA1 and BRCA2 equally contributed to site-specific breast cancers who had one/two breast cancer-affected first-/second-degree relative(s) or who were diagnosed within age 40 years in the absence of family history. This is consistent with recent data that indicated that the respective frequencies of BRCA1 and BRCA2 mutations are comparable in early onset breast cancer. Considering the total population of patients analyzed here, however, BRCA1 and BRCA2 mutations were mostly found in cases with disease diagnosis before and after age 50 years, respectively. Moreover, in cases with familial clustering of site-specific breast cancer, BRCA1 mostly accounted for tumours diagnosed before age 40 years, and BRCA2 for tumours diagnosed after age 50 years. This is in agreement with a trend, which has been observed in other populations, for the proportion of cases with BRCA2 mutations to increase, and the proportion with mutations in BRCA1 to decrease, as the age at cancer onset increases. As in other studies, the frequency of BRCA1/BRCA2 mutations taken together was lower than the estimated frequencies at comparable ages for all susceptibility alleles derived from the Contraceptive and Steroid Hormones (CASH) study. The discrepancy between direct data deriving from BRCA1/BRCA2 mutational analysis and CASH estimates could be due to several factors, including contribution of gene(s) other than BRCA1/BRCA2, differences between populations and relative insensitivity of mutational screening. Only BRCA1 mutations were found in breast/ovarian and site-specific ovarian cancer families. BRCA2, but not BRCA1 mutations were found in the male breast cancers. The overall proportion of males with BRCA2 mutations was high when compared with data from other studies on outbred populations, but was low compared with data from populations with founder effects. The present results should be regarded as an approximation, because the following types of mutation are predicted to escape detection by the screening strategy used: mutations in noncoding regions; missense mutations within BRCA1 exon 11 and BRCA2 exons 10 and 11; large gene deletions; and mutations within the first and last 180 nucleotides of the amplicons analyzed by PTT

Fluorouracil and dose-dense chemotherapy in adjuvant treatment of patients with early-stage breast cancer: An open-label, 2 × 2 factorial, randomised phase 3 trial

Background: Whether addition of fluorouracil to epirubicin, cyclophosphamide, and paclitaxel (EC-P) is favourable in adjuvant treatment of patients with node-positive breast cancer is controversial, as is the benefit of increased density of dosing. We aimed to address these questions in terms of improvements in disease-free survival. METHODS: In this 2 × 2 factorial, open-label, phase 3 trial, we enrolled patients aged 18-70 years with operable, node positive, early-stage breast cancer from 81 Italian centres. Eligible patients were randomly allocated in a 1:1:1:1 ratio with a centralised, interactive online system to receive either dose-dense chemotherapy (administered intravenously every 2 weeks with pegfilgrastim support) with fluorouracil plus EC-P (FEC-P) or EC-P or to receive standard-interval chemotherapy (administered intravenously every 3 weeks) with FEC-P or EC-P. The primary study endpoint was disease-free survival, assessed with the Kaplan-Meier method in the intention-to-treat population. Our primary comparisons were between dose schedule (every 2 weeks vs every 3 weeks) and dose type (FEC-P vs EC-P). This study is registered with ClinicalTrials.gov, number NCT00433420. FINDINGS: Between April 24, 2003, and July 3, 2006, we recruited 2091 patients. 88 patients were enrolled in centres that only provided standard-intensity dosing. After a median follow-up of 7·0 years (interquartile range [IQR] 4·5-6·3), 140 (26%) of 545 patients given EC-P every 3 weeks, 157 (29%) of 544 patients given FEC-P every 3 weeks, 111 (22%) of 502 patients given EC-P every 2 weeks, and 113 (23%) of 500 patients given FEC-P every 2 weeks had a disease-free survival event. For the dose-density comparison, disease-free survival at 5 years was 81% (95% CI 79-84) in patients treated every 2 weeks and 76% (74-79) in patients treated every 3 weeks (HR 0·77, 95% CI 0·65-0·92; p=0·004); overall survival rates at 5 years were 94% (93-96) and 89% (87-91; HR 0·65, 0·51-0·84; p=0·001) and for the chemotherapy-type comparison, disease-free survival at 5 years was 78% (75-81) in the FEC-P groups and 79% (76-82) in the EC-P groups (HR 1·06, 0·89-1·25; p=0·561); overall survival rates at 5 years were 91% (89-93) and 92% (90-94; 1·16, 0·91-1·46; p=0·234). Compared with 3 week dosing, chemotherapy every 2 weeks was associated with increased rate of grade 3-4 of anaemia (14 [1·4%] of 988 patients vs two [0·2%] of 984 patients; p=0·002); transaminitis (19 [1·9%] vs four [0·4%]; p=0·001), and myalgias (31 [3·1%] vs 16 [1·6%]; p=0·019), and decreased rates of grade 3-4 neutropenia (147 [14·9%] vs 433 [44·0%]; p<0·0001). Addition of fluorouracil led to increased rates of grade 3-4 neutropenia (354 [34·5%] of 1025 patients on FEC-P vs 250 [24·2%] of 1032 patients on EC-P; p<0·0001), fever (nine [0·9%] vs two [0·2%]), nausea (47 [4·6%] vs 28 [2·7%]), and vomiting (32 [3·1%] vs 15 [1·4%]). INTERPRETATION: In patients with node-positive early breast cancer, dose-dense adjuvant chemotherapy improved disease-free survival compared with standard interval chemotherapy. Addition of fluorouracil to a sequential EC-P regimen was not associated with an improved disease-free survival outcome

Prospective validation of the CLIP score: a new prognostic system for patient with cirrhosis and hepatocellular carcinoma

Prognosis of patients with cirrhosis and hepatocellular carcinoma (HCC) depends on both residual liver function and tumor extension. The CLIP score includes Child-Pugh stage, tumor morphology and extension, serum alfa-fetoprotein (AFP) levels, and portal vein thrombosis. We externally validated the CLIP score and compared its discriminatory ability and predictive power with that of the Okuda staging system in 196 patients with cirrhosis and HCC prospectively enrolled in a randomized trial. No significant associations were found between the CLIP score and the age, sex, and pattern of viral infection. There was a strong correlation between the CLIP score and the Okuda stage, As of June 1999, 150 patients (76.5%) had died. Median survival time was 11 months, overall, and it was 36, 22, 9, 7, and 3 months for CLIP categories 0, 1, 2, 3, and 4 to 6, respectively. In multivariate analysis, the CLIP score had additional explanatory power above that of the Okuda stage. This was true for both patients treated with locoregional therapy or not. A quantitative estimation of 2-year survival predictive power showed that the CLIP score explained 37% of survival variability, compared with 21% explained by Okuda stage. In conclusion, the CLIP score, compared with the Okuda staging system, gives more accurate prognostic information, is statistically more efficient, and has a greater survival predictive power. It could be useful in treatment planning by improving baseline prognostic evaluation of patients with RCC, and could be used in prospective therapeutic trials as a stratification variable, reducing the variability of results owing to patient selection

Evidence in hypertensive rats of hypotensive effect after mandibular extension

Previous studies in anesthetized normotensive rats demonstrated that a single mouth opening for 10 min obtained by an ad hoc dilator (mandibular extension [ME]) produced a blood pressure reduction by about 20 mmHg lasting for about 2 h and that once-repeated ME prolonged this effect. We here describe these effects in hypertensive rats. Mean (intra) arterial blood pressure (MABP) and heart rate (HR) was followed for up to a maximum of 470 min after single or repeated 10 min-lasting ME in two groups of anesthetized, male, 6-9 months old hypertensive rats. In one group, hypertension was induced by dexamethasone (20 μg/kg/day, subcutaneously for 7 days; Dex-HT); the other group was spontaneously hypertensive rats (SHR). Studies were done, in Dex-HT rats, after only surgical procedures (no ME, sham-operated rats), single ME, early repeated (after 10 min) ME (ER-ME) and late repeated (after 160 min) ME (LR-ME) and, in SHR, after only surgical procedures and ER-ME. One-way ANOVA for repeated measures revealed no significant effect on MABP and HR in sham-operated groups. In Dex-HT rats, single ME was followed by a significant MABP decline by 25 mmHg, lasting for 100 min; ER-ME and LR-ME were followed by an even greater significant MABP decline by 40 mmHg, which outlasted the experimental observation period. In SHR, ER-ME gave similar results as in Dex-HT rats. HR significantly declined in all, except sham-operated groups. In conclusions, ME is followed by a prolonged MABP decline also in hypertensive rats. This effect is even more pronounced, in length and magnitude, after repeated ME

Vascular Disrupting Agents: A Novel Mechanism of Action in the Battle against Non-Small Cell Lung Cancer

1. Explain the molecular mechanism of action of vascular disrupting agents. Evaluate the preclinical results of vascular disrupting agents. 3. Assess the preliminary clinical results of vascular disrupting agents in the treatment of patients with NSCLC. This article is available for continuing medical education credit at CME.TheOncologist.com. The aim of this review is to discuss the hypothesized molecular mechanisms of action of VDAs and their early preclinical and clinical results, emphasizing ASA404, combretastatin A-4 disodium phosphate, ABT-751, and NPI-2358, reported in the treatment of non-small cell lung cancer, which is the leading cause of cancer death worldwide, and also to discuss future developments in this cancer population. The Oncologist CME CME ABSTRAC

EFFECTS OF TRIGEMINAL NERVE STIMULATION BY MANDIBULAR EXTENSION ON RAT PIAL MICROCIRCULATION: ROLE OF NITRIC OXIDE

In the present study we have extended our previous findings about the effects of 10 minutes of passive mandibular extension in anesthetized Wistar rats. By prolonging the observation time to 3 hours, we showed that 10 minutes mandibular extension caused a significant reduction of the mean arterial blood pressure and heart rate respect to baseline values, which persisted up to 160 minutes after mandibular extension. These effects were accompanied by a characteristic biphasic response of pial arterioles: during mandibular extension, pial arterioles constricted and after mandibular extension dilated for the whole observation period. Interestingly, the administration of the opioid receptor antagonist naloxone abolished the vasoconstriction observed during mandibular extension, while the administration of N?-Nitro-L-arginine methyl ester, a nitric oxide synthase inhibitor, abolished the vasodilation observed after mandibular extension. Either drug did not affect the reductions of mean arterial blood pressure and heart rate induced by mandibular extension. By qRT-PCR, we also showed that neuronal nitric oxide synthase gene expression was significantly increased compared with baseline conditions during and after mandibular extension and endothelial nitric oxide synthase gene expression markedly increased at 2 hours after mandibular extension. Finally, western blotting detected a significant increase in neuronal and endothelial nitric oxide synthase protein expression. In conclusion mandibular extension caused complex effects on pial microcirculation involving opioid receptor activation and nitric oxide release by both neurons and endothelial vascular cells at different times