trans-[Ru(NO)(NH(3))(4)(py)](BF(4))(3)center dot H(2)O encapsulated in PLGA microparticles for delivery of nitric oxide to B16-F10 cells: Cytotoxicity and phototoxicity

The NO donor trans-[Ru(NO)(NH(3))(4)(py)](BF(4))(3).H(2)O (py = pyridine) was loaded into poly-lactic-co-glycolic acid (PLGA) microparticles using the double emulsification technique. Scanning electron microscopy (SEM) and dynamic light scattering revealed that the particles are spherical in shape, have a diameter of 1600 nm, and have low tendency to aggregate. The entrapment efficiency was 25%. SEM analysis of the melanoma cell B16-F10 in the presence of the microparticles containing the complex trans-[Ru(NO)(NH(3))(4)(py)](BF(4))(3).H(2)O (pyMP) showed that the microparticles were adhered to the cell surface after 2 h of incubation. The complex with concentrations lower than 1 x 10(-4) M did not show toxicity in B16-F 10 murine cells. The complex in solution is toxic at higher concentrations (> 1 x 10(-3) M), with cell death attributed to NO release following the reduction of the complex. pyMP is not cytotoxic due to the lower bioavailability and availability of the entrapped complex to the medium and its reducing agents. However, pyMP is phototoxic upon light irradiation. The phototoxicity strongly suggests that cell death is due to NO release from trans-[Ru(NO)(NH(3))(4)(py)](3+). This work shows that pyMP can serve as a model for a drug delivery system carrying the NO donor trans-[Ru(NO)(NH(3))(4)(py)](BF(4))(3).H(2)O, which can release NO locally at the tumor cell by radiation with light only. (c) 2007 Elsevier Inc. All rights reserved.

Effects of acute magnesium loading on pulmonary function of stable COPD patients

Background: Magnesium (Mg) use has the potential to promote bronchodilatation and to improve lung function in obstructive diseases. IV administration of Mg during exacerbations of chronic obstructive pulmonary disease (COPD) has led to improved peak flow. This study aimed to investigate the effects of acute IV Mg loading on respiratory parameters of stable COPD patients. Material/Methods: This was a randomized, double-blind, placebo-controlled crossover study. Twenty-two male COPD patients (64 +/- 6 years old, FEV1: 49 +/- 20%) received an IV infusion of 2 g of magnesium sulfate or placebo on two distinct occasions. Spirometry and mouth maximal respiratory pressures were obtained before and 45 minutes after the infusions. Results: Mg use led to significant changes in functional respiratory capacity (-0.48 1,95% CI: -0.96, -0.01), inspiratory capacity (0.21 1,95% CI: 0.04, 0.37). The treatment was also associated with a marginally significant decrease in residual volume (-0.47 1,95% CI: -0.96, 0.02, p=0.06). Conclusions: Acute IV Mg loading in stable COPD patients was associated with a reduction in lung hyperinflation and improvement of respiratory muscle strength. The clinical potential for chronic magnesium supplementation in COPD deserves further investigation.

Role of mixed Th1 and Th2 serum cytokines on pathogenesis and prognosis of hantavirus pulmonary syndrome

The hantavirus pulmonary syndrome (HPS) is an emerging syndrome in the Americas. The disease results from intense immune activation and changes in vascular permeability. The aim of this study was to determine the profile of serum cytokines in HPS patients looking for correlation with the clinical parameters, severity and outcome of illness. Studying 21 HPS patients, we found that IL-6 may have an important role in the pathogenesis of HPS, being associated with fatal outcome. Our results also support a mixed Th1/Th2 immune response during the course of HPS and that the magnitude of Th1 response effector cytokines is correlated to HPS severity. The decreased levels of TGF-beta observed in HPS patients suggest that immunoregulatory activity could be damaged in these patients. (c) 2008 Elsevier Masson SAS. All rights reserved.

Effects of Inspiratory Muscle Training on Muscular and Pulmonary Function After Bariatric Surgery in Obese Patients

This study seeks to assess the effect of inspiratory muscle training (IMT) on pulmonary function, respiratory muscle strength, and endurance in morbidly obese patients submitted to bariatric surgery. Thirty patients were randomly assigned to sham muscular training, or to IMT with a threshold device (40% of maximum inspiratory pressure, MIP), for 30 min/day, from the 2nd until 30th postoperative (PO) day. All of them were submitted to a standard respiratory kinesiotherapy and early deambulation protocol. Data on spirometry, maximum static respiratory pressures, and respiratory muscle endurance were collected on the PO days 2, 7, 14, and 30 in a blinded matter. IMT enabled increases in PO MIP and endurance, and an earlier recovery of the spirometry parameters FEV(1), PEF, and FEF(25-75%). Comparing to preoperative values, MIP was increased by 13% at the 30th PO day in the trained group, whereas control group had a reduction of 8%, with higher values for the IMT group (30th PO, IMT-130.6 +/- 22.9 cmH(2)O; controls-112.9 +/- 25.1 cmH(2)O; p < 0.05). Muscular endurance at the 30th PO day was increased in the trained group comparing to preoperative value (61.5 +/- 39.6 s vs 114.9 +/- 55.2 s; p < 0.05), a finding not observed in the control group (81.7 +/- 44.3 vs 95.2 +/- 42.0 s). IMT improves inspiratory muscle strength and endurance and accounts for an earlier recovery of pulmonary airflows in morbidly obese patients submitted to bariatric surgery.

Dose-dependent beneficial hemodynamic effects of BAY 41-2272 in a canine model of acute pulmonary thromboembolism

The current therapy of acute pulmonary embolism is focused on removing the mechanical obstruction of the pulmonary vessels. However, accumulating evidence suggests that pulmonary vasoconstriction drives many of the hemodynamic changes found in this condition. We examined the effects of stimulation of soluble guanylate cyclase with BAY 41-2272 (5-Cyclopropyl-2-[1-(2-fluoro-benzyl)-1H-pyrazolo[3,4-b]pyridin-3-yl]-pyrimidin-4-ylamine) in an anesthetized dog model of acute pulmonary embolism. Hemodynamic and arterial blood gas evaluations were performed in non-embolized dogs treated with vehicle (N = 5), and in embolized dogs (intravenous injections of microspheres) that received BAY 41-2272 intravenously in doses of 0.03, 0.1, 0.3, and 1 mg/kg/h or vehicle (1 ml/kg/h of 1.13% ethanol in saline, volume/volume). Plasma cGMP and thiobarbituric acid reactive substances concentrations were determined using a commercial enzyme immunoassay and a fluorometric method, respectively. The infusion of BAY 41-2272 resulted in a decrease in pulmonary artery pressure by similar to 29%, and in pulmonary vascular resistance by similar to 46% of the respective increases induced by lung embolization (both P<0.05). While the higher doses of BAY 41-2272 produced no additional effects on the pulmonary circulation, they caused significant arterial hypotension and reduction in systemic vascular resistance (both P<0.05). Although BAY 41-2272 increased cGMP concentrations (P<0.05), it did not affect the hypoxemia and the increased oxidative stress caused by lung embolization. These results suggest that stimulation of soluble guanylate cyclase with low (but not high) doses of BAY 41-2272 produces selective pulmonary vasodilation during acute pulmonary embolism. The dose-dependent systemic effects produced by BAY 41-2272, however, may limit its usefulness in larger doses. (C) 2007 Elsevier B.V. All rights reserved.

Severity dependent increases in circulating cardiac troponin I and MMP-9 concentrations after experimental acute pulmonary thromboembolism

Background: Making the diagnosis of acute pulmonary thromboembolism (APT) and assessing its severity is very challenging, While cardiac troponin I (cTnI) concentrations are promising in risk stratification, no previous study has examined whether there is a linear relation between cTnI concentrations and the severity of APT. Moreover, matrix metalloprotemases (MMPs) are involved in the pathophysiology of APT. However, it is unknown whether the increases in MMP concentrations after APT reflect the severity of this condition. We examined whether the circulating concentrations of these biomarkers increase in proportion to the severity of experimental APT induced in anesthetized dogs. Methods: APT was induced with autologous blood clots (saline, 1, 3, or 5 ml/kg) injected into the right atrium. Hemodynamic evaluations were carried out for 120 min. Gelatin zymography of MMP-2 and MMP-9 from plasma samples were performed and serum cTnI concentrations were determined at baseline and 120 min after APT. Results: While no significant increases in pro-MMP-2 concentrations were found after APT, pro-MMP-9 concentrations increased by 80% only after 5 ml/kg of clot embolization. Serum cTnI and plasma pro-MMP-9 concentrations correlated positively with pulmonary vascular resistance (P=0.007 and rs=0.833 for troponin 1, and P=0.034 and rs=0.684 for pro-MMP-9) and with pulmonary artery pressure (P=0.005 and rs=0.610 for troponin 1, and P=0.022 and rs=0.720 for pro-MMP-9). Conclusions: Circulating cTnI and pro-MMP-9 increase in proportion to the severity of APT, although the increases in plasma pro-MMP-9 are less clear with less severe APT. These findings may be relevant for clinical APT. (C) 2007 Elsevier B.V. All rights reserved.

Increases in circulating matrix metalloproteinase-9 levels following fibrinolysis for acute pulmonary embolism

Introduction: Fibrinolyis is one of the first line therapies in high risk pulmonary embolism (PE) according to current guidelines. Previous studies showed that brinolytic therapy with tPA (tissue plasminogen activator, or alteplase) upregulates the concentrations of matrix metalloproteinases (MMPs) and contributes to hemorrhagic transformation after cardioembolic stroke. However, no previous study has described the circulating MMPs levels following fibrinolysis for acute PE. Materials and Methods: We serially measured the circulating levels of MMPs (MMP-9 and MMP-2) and their endogenous inhibitors, the tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2 in alteplase and in streptokinase-treated patients with acute PE by gelatin zymography and by enzyme-linked immunosorbent assays, respectively. Results: We found that therapy of PE streptokinase or with alteplase is associated increased pro-MMP-9, but not MMP-2, concentrations for up to 24 hours, whereas no significant changes were found in TIMP-1 or TIMP-2 concentrations. This alteration returned to normal 3 to 5 days after thrombolysis. This is the first study reporting on MMPs alterations following fibrinolysis for acute PE. Conclusions: We found transient increases in circulating pro-MMP-9 levels following fibrinolysis for acute PE. Our findings support the hypothesis that increased MMP-9 levels may underlie the risk of intracerebral hemorrhage or other bleeding complication of thrombolysis for acute PE, and the use of MMP inhibitors may decrease such risk. (C) 2010 Elsevier Ltd. All rights reserved.

Uridine adenosine tetraphosphate-induced contraction is increased in renal but not pulmonary arteries from DOCA-salt hypertensive rats

Matsumoto T, Tostes RC, Webb RC. Uridine adenosine tetraphosphate-induced contraction is increased in renal but not pulmonary arteries from DOCA-salt hypertensive rats. Am J Physiol Heart Circ Physiol 301: H409-H417, 2011. First published May 6, 2011; doi:10.1152/ajpheart.00084.2011.-Uridine adenosine tetraphosphate (Up(4)A) was reported as a novel endothelium-derived contracting factor. Up(4)A contains both purine and pyrimidine moieties, which activate purinergic (P2)X and P2Y receptors. However, alterations in the vasoconstrictor responses to Up(4)A in hypertensive states remain unclear. The present study examined the effects of Up(4)A on contraction of isolated renal arteries (RA) and pulmonary arteries (PA) from DOCA-salt rats using isometric tension recording. RA from DOCA-salt rats exhibited increased contraction to Up(4)A versus arteries from control uninephrectomized rats in the absence and presence of N(G)-nitro-L-arginine (nitric oxide synthase inhibitor). On the other hand, the Up(4)A-induced contraction in PA was similar between the two groups. Up(4)A-induced contraction was inhibited by suramin (nonselective P2 antagonist) but not by diinosine pentaphosphate pentasodium salt hydrate (Ip5I; P2X(1) antagonist) in RA from both groups. Furthermore, 2-thiouridine 5`-triphosphate tetrasodium salt (2-Thio-UTP; P2Y(2) agonist)-, uridine-5`-(gamma-thio)-triphosphate trisodium salt (UTP gamma S; P2Y(2)/P2Y(4) agonist)-, and 5-iodouridine-5`-O-diphosphate trisodium salt (MRS 2693; P2Y(6) agonist)-induced contractions were all increased in RA from DOCA-salt rats. Protein expression of P2Y(2)-, P2Y(4)-, and P2Y(6) receptors in RA was similar between the two groups. In DOCA-salt RA, the enhanced Up(4)A-induced contraction was reduced by PD98059, an ERK pathway inhibitor, and Up(4)Astimulated ERK activation was increased. These data are the first to indicate that Up(4)A-induced contraction is enhanced in RA from DOCA-salt rats. Enhanced P2Y receptor signaling and activation of the ERK pathway together represent a likely mechanism mediating the enhanced Up(4)A-induced contraction. Up(4)A might be of relevance in the pathophysiology of vascular tone regulation and renal dysfunction in arterial hypertension.

Comparison of pelvic floor muscle strength between women undergoing vaginal delivery, cesarean section, and nulliparae using a perineometer and digital palpation

Objectives. To compare pelvic floor muscle (PFM) strength between women undergoing vaginal delivery, cesarean section, and nulliparae, investigating the factors associated with PFM strength, and observing the correlation between vaginal digital palpation and use of a perineometer. Methods. A cross-sectional study was conducted, including 31 women following vaginal delivery, 30 women following cesarean section, and 30 nulliparous women. PFM strength was measured by vaginal digital palpation and use of a perineometer. Multiple linear regression analysis with adjustment for covariables was used to compare the mean PFM strength and identify its associated factors. Results. The mean PFM strength of women undergoing vaginal delivery and cesarean section was 25.6 +/- 14.5 cmH(2)O and 39.6 +/- 22.0 cmH(2)O (p < 0.01, adjusted for covariables), respectively. A correlation was observed between measurements of PFM strength obtained by vaginal digital palpation and use of a perineometer (tau = 0.82; p < 0.01). The non-white race/ethnicity was negatively associated with PFM strength (coefficient: -10.2424; p = 0.02). Conclusions. A lower PFM strength was observed in women with a history of vaginal delivery compared to those undergoing cesarean section. Non-white race/ethnicity negatively affected PFM strength. Our data suggest that vaginal digital palpation may be used in clinical practice because of its expressive correlation with use of a perineometer.

Tuberculosis incidence among contacts of active pulmonary tuberculosis

BACKGROUND: Treatment of latent tuberculosis (TB) infection (LTBI) in Brazil is recommended only in the case of contacts of pulmonary smear-positive TB patients aged <= 15 years with a tuberculin skin test (TST) >= 10 mm and no previous bacille Calmette-Guerin (BCG) vaccination or with a TST >= 15 mm regardless of previous BCG vaccination. OBJECTIVE: To evaluate the 2-year incidence and predictors of TB among contacts who did not meet the Brazilian criteria for LTBI treatment. DESIGN: Retrospective cohort study. Contacts aged between 12 and 15 years and those aged >15 years who did not meet the Brazilian criteria for LTBI treatment were enrolled in the study. RESULTS: TB incidence was 3.2% (22/667), with an estimated TB rate of 1649 per 100000 population. Risk of TB was greater among the 349 contacts with TST >= 5 mm (5.4%) compared to the 318 contacts with TST <5 mm, (0.9%; RR 6.04, 95%CI 1.7-20.6). CONCLUSION: The high incidence of TB among contacts who did not meet the Brazilian criteria for LTBI treatment strongly suggests that these criteria should be reviewed. Furthermore, even among BCG-vaccinated contacts, TST induration >= 5 mm, was the only variable that predicted the development of TB disease within 2 years.

Cesarean delivery is associated with an increased risk of obesity in adulthood in a Brazilian birth cohort study

Background: Obesity is epidemic worldwide, and increases in cesarean delivery rates have occurred in parallel. Objective: This study aimed to determine whether cesarean delivery is a risk factor for obesity in adulthood in a birth cohort of Brazilian subjects. Design: We initiated a birth cohort study in Ribeirao Preto, southeastern Brazil, in 1978. A randomly selected sample of 2057 subjects from the original cohort was reassessed in 2002-2004. Type of delivery, birth weight, maternal smoking, and schooling were obtained after birth. The following data from subjects were collected at 23-25 y of age: body mass index (BMI; in kg/m(2)), physical activity, smoking, and income. Obesity was defined as a BMI >= 30. A Poisson multivariable model was performed to determine the association between cesarean delivery and BMI. Results: The obesity rate in adults born by cesarean delivery was 15.2% and in those born by vaginal delivery was 10.4% (P = 0.002). Adults born by cesarean delivery had an increased risk (prevalence ratio: 1.58; 95% CI: 1.23, 2.02) of obesity at adulthood after adjustments. Conclusion: We hypothesize that increasing rates of cesarean delivery may play a role in the obesity epidemic worldwide. Am J Clin Nutr 2011;93:1344-7.

Nitrite or sildenafil, but not BAY 41-2272, blunt acute pulmonary embolism-induced increases in circulating matrix metalloproteinase-9 and oxidative stress

Introduction: Inhibition of matrix metalloproteinases (MMPs) improves the hemodynamics during acute pulmonary embolism (APE) and oxidative stress upregulates MMPs. We compared the effects of different NO-cGMP pathway activators on APE-induced increases in MMPs. Materials and Methods: Hemodynamic and biochemical evaluations were performed in non-embolized dogs treated with saline (N = 5), and in microspheres embolized dogs receiving saline (n = 9), or nitrite (6.75 mu mol/kg i.v. over 15 min followed by 0.28 mu mol/kg/min; n = 5), or sildenafil (0.25 mg/kg; n = 5), or BAY 41-2272 (0.03, 0.1, 0.3, and 1 mg/kg/h; n = 5). Plasma thiobarbituric acid reactive substances (TBARS) concentrations were determined. Zymograms of plasma samples were performed, and in vitro antioxidant effects or inhibition of MMPs by these drugs were examined. Results: APE increased mean pulmonary artery pressure by similar to 25 mmHg. Nitrite, BAY 41-2272, or sildenafil reversed this increase by similar to 40% (P < 0.05). Similar effects were seen on the pulmonary vascular resistance. While both nitrite and sildenafil produced no systemic effects, the highest dose of BAY 41-2272 produced systemic hypotension (P<0.05). While nitrite and sildenafil blunted the increases in plasma pro-MMP-9 levels and TBARS (all P < 0.05), BAY 41-2272 produced no such effects. Nitrite and sildenafll produced in vitro antioxidant effects and inhibited MMPs only at high concentrations. BAY 41-2272 produced no such effects. Conclusions: Activation of the NO-cGMP pathway with nitrite or sildenafil, but not with BAY 41-2272, attenuates APE-induced oxidative stress and increased MMP-9 levels. These findings are consistent with the idea that NO-cGMP pathway activators with antioxidant effects prevent the release of MMP-9 during APE. (c) 2008 Elsevier Ltd. All rights reserved.

Role of sensory innervation in the rat pulmonary neutrophil recruitment induced by staphylococcal enterotoxins type A and B

Rat airways exposure to Staphylococcal enterotoxin A (SEA) and B (SEB) induces marked neutrophil influx. Since sensory neuropeptides play important roles in cell infiltration, in this study we have investigated its contribution in triggering SEA- and SEB-induced pulmonary neutrophil infiltration. Male Wistar rats were exposed intratracheally with SEA (3 ng/trachea) or SEB (250 ng/trachea). Animals received different in vivo pretreatments, after which the neutrophil counts and levels of substance P and IL-1 in bronchoalveolar lavage fluid were evaluated. Alveolar macrophages and peritoneal mast cells were incubated with SEA and SEB to determine the IL-1 and TNF-alpha levels. Capsaicin pretreatment significantly reduced SEA- and SEB-induced neutrophil influx in bronchoalveolar lavage fluid, but this treatment was more effective to reduce SEA responses. Treatments with SR140333 (tachykinin NK(1) receptor antagonist) and SR48968 (tachykinin NK(2) receptor antagonist) decreased SEA-induced neutrophil influx, whereas SEB-induced responses were inhibited by SR140333 only. Cyproheptadine (histamine/5-hydroxytriptamine receptor antagonist) and MD 7222 (5-HT(3) receptor antagonist) reduced SEA- and SEB-induced neutrophil influx. The substance P and IL-1 levels in bronchoalveolar lavage fluid of SEA-exposed rats were significantly hi.-her than SEB. In addition, SEA (but not SEB) significantly released mast cell TNF-alpha. Increased production of TNF-alpha and IL-1 in alveolar macrophages was observed in response to SEA and SEB. In conclusion, sensory neuropeptides contribute significantly to SEA- and SEB-induced pulmonary neutrophil recruitment, but SEA requires in a higher extent the airways sensory innervation, and participation of mast cells and alveolar macrophage products. (C) 2009 Elsevier B.V. All rights reserved.

Sildenafil improves the beneficial haemodynamic effects of intravenous nitrite infusion during acute pulmonary embolism

Acute pulmonary embolism produces acute pulmonary hypertension, which can be counteracted by activating the nitric oxide-cyclic guanosine 3`,5`-monophosphate (cGMP) pathway. While previous studies have shown that sildenafil (an inhibitor of cGMP-specific phosphodiesterase type 5) or nitrite (a storage molecule for nitric oxide) produces beneficial effects during acute pulmonary embolism, no previous study has examined whether the combination of these drugs can produce additive effects. Here, we expand previous findings and examine whether sildenafil enhances the beneficial haemodynamic effects produced by a low-dose infusion of nitrite in a dog model of acute pulmonary embolism. Haemodynamic and arterial blood gas evaluations were performed in non-embolized dogs treated with saline (n = 4), and in embolized dogs (intravenous injections of microspheres) that received nitrite (6.75 mu mol/kg intravenously over 15 min. followed by 0.28 mu mol/kg/min.) and sildenafil (0.25 mg/kg over 30 min.; n = 8), or nitrite followed by saline (n = 8), or saline followed by sildenafil (n = 7), or only saline (n = 8). Plasma thiobarbituric acid-reactive substances (TBARS) concentrations were determined using a fluorometric method. Acute pulmonary embolism increased pulmonary artery pressure by similar to 24 mmHg. While the infusion of nitrite or sildenafil infusions reversed this increase by similar to 42% (both P < 0.05), the combined infusion of both drugs reversed this increase by similar to 58% (P < 0.05). Similar effects were seen on the pulmonary vascular resistance index. Nitrite or sildenafil alone produced no significant hypotension. However, the combined infusion of both drugs caused transient hypotension (P < 0.05). Both dugs, either alone or combined, blunted the increase in TBARS concentrations caused by acute pulmonary embolism (all P < 0.05). These results suggest that sildenafil improves the beneficial haemodynamic effects of nitrite during acute pulmonary embolism.