Chronic exposure to ambient levels of urban particles affects mouse lung development

Rationale- Chronic exposure to air pollution has been associated with adverse effects on children`s lung growth. Objectives: We analyzed the effects of chronic exposure to urban levels of particulate matter (PM) on selected phases of mouse lung development. Methods: The exposure occurred in two open-top chambers (filtered and nonfiltered) placed 20 m from a street with heavy traffic in Sao Paulo, 24 hours/day for 8 months. There was a significant reduction of the levels of PM(2.5) inside the filtered chamber (filtered = 2.9 +/- 3.0 mu g/m(3), nonfiltered = 16.8 +/- 8.3 mu g/m(3); P = 0.001). At this exposure site, vehicular sources are the major components of PM(2.5) (PM <= 2.5 mu m). Exposure of the parental generation in the two chambers occurred from the 10th to the 120th days of life. After mating and birth of offspring, a crossover of mothers and pups occurred within the chambers, resulting in four groups of pups: nonexposed, prenatal, postnatal, and pre+postnatal. Offspring were killed at the age of 15 (n = 42) and 90 (n = 35) days; lungs were analyzed by morphometry for surface to volume ratio (as an estimator of alveolization). Pressure-volume curves were performed in the older groups, using a 20-ml plethysmograph. Measurements and Main Results: Mice exposed to PM(2.5) pre+postnatally presented a smaller surface to volume ratio when compared with nonexposed animals (P = 0.036). The pre+postnatal group presented reduced inspiratory and expiratory volumes at higher levels of transpulmonary pressure (P = 0.001). There were no differences among prenatal and postnatal exposure and nonexposed animals. Conclusions: Our data provide anatomical and functional support to the concept that chronic exposure to urban PM affects lung growth.

The role of BPH, lower urinary tract symptoms, and PSA levels on erectile function of Brazilian men who undergo prostate cancer screening

Introduction. Lower urinary tract symptoms (LUTS) and erectile dysfunction (ED) are common problems in middle-aged and older men. Recently, epidemiologic studies have shown significant associations between severity of LUTS and male sexual dysfunction. Aim. We analyzed the role of prostate enlargement, LUTS, and prostate specific antigen (PSA) levels in the erectile function of Brazilian men who underwent prostate cancer (PCa) screening. Method. We analyzed data from 1,008 consecutive patients enrolled in a PCa screening program. Benign prostatic hyperplasia (BPH) was defined as a prostate weight greater than 30 g as defined by digital rectal examination. For statistical analysis, we used the chi-squared and analysis of variance tests. The odds ratios (OR) for correlation of ED with prostate volume LUTS and PSA were estimated using logistic regression models. Main Outcome Measure. The American Urological Association (AUA) symptom score for LUTS and the International Index of Erectile Function. Results. Mean patient age was 61.2 years (45-87) and median PSA value was 1.9 ng/mL. BPH was identified in 48.5% of patients. Mild, moderate, and severe LUTS were found in 52.3%, 30.9%, and 16.8% of cases, respectively. ED was classified as absent, mild, mild to moderate, moderate, and severe in 18.6%, 23.1%, 18.6%, 15.2%, and 24.5%, respectively. While only 5.4% of the patients with no ED presented severe LUTS, this finding was observed in 27.1% of patients with severe ED (P<0.001). Univariate logistic regression analysis demonstrated that age, prostate volume, AUA symptom score, and PSA levels were significant predictors of ED. However, when controlled for patient age, only LUTS remained as an independent predictor of ED. Conclusions. Controlling for patient age, LUTS are independent risk factors for the development of ED among Brazilian men who undergo PCa screening.

Understanding the genetic diversity, spatial genetic structure and mating system at the hierarchical levels of fruits and individuals of a continuous Theobroma cacao population from the Brazilian Amazon

Understanding the mating patterns of populations of tree species is a key component of ex situ genetic conservation. In this study, we analysed the genetic diversity, spatial genetic structure (SGS) and mating system at the hierarchical levels of fruits and individuals as well as pollen dispersal patterns in a continuous population of Theobroma cacao in Para State, Brazil. A total of 156 individuals in a 0.56 ha plot were mapped and genotyped for nine microsatellite loci. For the mating system analyses, 50 seeds were collected from nine seed trees by sampling five fruits per tree (10 seeds per fruit). Among the 156 individuals, 127 had unique multilocus genotypes, and the remaining were clones. The population was spatially aggregated; it demonstrated a significant SGS up to 15m that could be attributed primarily to the presence of clones. However, the short seed dispersal distance also contributed to this pattern. Population matings occurred mainly via outcrossing, but selfing was observed in some seed trees, which indicated the presence of individual variation for self-incompatibility. The matings were also correlated, especially within ((r) over cap (p(m)) = 0.607) rather than among the fruits ((r) over cap (p(m)) = 0.099), which suggested that a small number of pollen donors fertilised each fruit. The paternity analysis suggested a high proportion of pollen migration (61.3%), although within the plot, most of the pollen dispersal encompassed short distances (28m). The determination of these novel parameters provides the fundamental information required to establish long-term ex situ conservation strategies for this important tropical species. Heredity (2011) 106, 973-985; doi:10.1038/hdy.2010.145; published online 8 December 2010

Human mucosal leishmaniasis: Neutrophils infiltrate areas of tissue damage that express high levels of Th17-related cytokines

Mucosal leishmaniasis (ML) is characterised by severe tissue destruction. Herein, we evaluated the involvement of the IL-17-type response in the inflammatory infiltrate of biopsy specimens from 17 ML patients. IL-17 and IL-17-inducing cytokines (IL-1 beta, IL-23, IL-6 and TGF-beta) were detected by immunohistochemistry in ML patients. IL-17(+) cells exhibited CD4(+), CD8(+) or CD14(+) phenotypes, and numerous IL-17(+) cells co-expressed the CC chemokine receptor 6 (CCR6). Neutrophils, a hallmark of Th17-mediated inflammation, were regularly detected in necrotic and perinecrotic areas and stained positive for neutrophil elastase, myeloperoxidase and MMP-9. Taken together, these observations demonstrate the existence of Th17 cells in ML lesions associated with neutrophils in areas of tissue injury and suggest that IL-17 is involved in ML pathogenesis.

Atrogin-1 and MuRF1 regulate cardiac MyBP-C levels via different mechanisms

Familial hypertrophic cardiomyopathy (FHC) is frequently caused by cardiac myosin-binding protein C (cMyBP-C) gene mutations, which should result in C-terminal truncated mutants. However, truncated mutants were not detected in myocardial tissue of FHC patients and were rapidly degraded by the ubiquitin-proteasome system (UPS) after gene transfer in cardiac myocytes. Since the diversity and specificity of UPS regulation lie in E3 ubiquitin ligases, we investigated whether the muscle-specific E3 ligases atrogin-1 or muscle ring finger protein-1 (MuRF1) mediate degradation of truncated cMyBP-C. Human wild-type (WT) and truncated (M7t, resulting from a human mutation) cMyBP-C species were co-immunoprecipitated with atrogin-1 after adenoviral overexpression in cardiac myocytes, and WT-cMyBP-C was identified as an interaction partner of MuRF1 by yeast two-hybrid screens. Overexpression of atrogin-1 in cardiac myocytes decreased the protein level of M7t-cMyBP-C by 80% and left WT-cMyBP-C level unaffected. This was rescued by proteasome inhibition. In contrast, overexpression of MuRF1 in cardiac myocytes not only reduced the protein level of WT- and M7t-cMyBP-C by > 60%, but also the level of myosin heavy chains (MHCs) by > 40%, which were not rescued by proteasome inhibition. Both exogenous cMyBP-C and endogenous MHC mRNA levels were markedly reduced by MuRF1 overexpression. Similar to cardiac myocytes, MuRF1-overexpressing (TG) mice exhibited 40% lower levels of MHC mRNAs and proteins. Protein levels of cMyBP-C were 29% higher in MuRF1 knockout and 34% lower in TG than in WT, without a corresponding change in mRNA levels. These data suggest that atrogin-1 specifically targets truncated M7t-cMyBP-C, but not WT-cMyBP-C, for proteasomal degradation and that MuRF1 indirectly reduces cMyBP-C levels by regulating the transcription of MHC.

Modulation of B-1 and B-2 kinin receptors expression levels in the hippocampus of rats after audiogenic kindling and with limbic recruitment, a model of temporal lobe epilepsy

Epileptic seizures are hypersynchronous, paroxystic and abnormal neuronal discharges. Epilepsies are characterized by diverse mechanisms involving alteration of excitatory and inhibitory neurotransmission that result in hyperexcitability of the central nervous system (CNS). Enhanced neuronal excitability can also be achieved by inflammatory processes, including the participation of cytokines, prostaglandins or kinins, molecules known to be involved in either triggering or in the establishment of inflammation. Multiple inductions of audiogenic seizures in the Wistar audiogenic rat (WAR) strain are a model of temporal lobe epilepsy (TLE), due to the recruitment of limbic areas such as hippocampus and amygdata. In this study we investigated the modulation of the B-1 and B-2 kinin receptors expression levels in neonatal WARs as well as in adult WARs subjected to the TLE model. The expression levels of pro-inflammatory (IL-1 beta) and anti-inflammatory (IL-10) cytokines were also evaluated, as well as cyclooxygenase (COX-2). Our results showed that the B-1 and B-2 kinin receptors mRNAs were up-regulated about 7- and 4-fold, respectively, in the hippocampus of kindled WARs. On the other hand, the expressions of the IL-1 beta, IL-10 and COX-2 were not related to the observed increase of expression of kinin receptors. Based on those results we believe that the B, and B2 kinin receptors have a pivotal role in this model of TLE, although their participation is not related to an inflammatory process. We believe that kinin receptors in the CNS may act in seizure mechanisms by participating in a specific kininergic neurochemical pathway. (c) 2007 Elsevier B.V. All rights reserved.

Determination of Kininogens Levels and Kallikrein/Kininase II Activities in Patients with Thromboangiitis Obliterans

Some components of the kinin system such as plasma kallikrein levels, the activities of tissue kallikrein (including saliva) and kininase II and the concentrations of kininogen fractions (low-molecular weight/LKg and high-molecular weight/HKg) were evaluated in the plasma of patients with thromboangiitis obliterans (TAO) presenting clinical symptoms of the condition. Twenty TAO were diagnosed by means of the traditional Shionoya and Olin criteria and later classified into non-smokers (n = 11) and active smokers (n = 9). Fifty-three normal, non-smoking/smoking individuals (control) were also studied. Kininogen levels were determined by ELISA; the activities of kallikreins and kininase II were determined using selective substrates. The levels of enzymes (kallikreins and kininase II) and protein (kininogens) were significantly higher in patients with TAO who were active smokers compared to the control groups (no matter whether control individuals were active smokers or non-smokers, P < 0.001 for all comparisons). Interestingly, regardless of the time of disease onset, a significant increase in the levels of these components of the kinin system was also observed in patients when TAO active smokers were compared with TAO ex-smokers (P < 0.01 for all analysed parameters). Activation of the kinin system in patients with TAO may indicate the involvement of vasodilatation in an attempt to control vascular changes, thereby favouring the deposition of immune complexes at the vascular level because of nicotine stimulation. Moreover, our results corroborate the idea that TAO can be an autoimmune disorder with specific mechanisms.

Effects of creatine supplementation on homocysteine levels and lipid peroxidation in rats

Hyperhomocysteinaemia is an independent risk factor for CVD. Recent data show a relationship between homocysteine (Hcy) and free radical formation. Since creatine synthesis is responsible for most of the methyl group transfers that result in Hcy formation, creatine supplementation might inhibit Hcy production and reduce free radical formation. The present study investigated the effects of creatine supplementation on Hcy levels and lipid peroxidation biomarkers. Thirty rats were divided into three groups: control group; diet with creatine group (DCr; 2% creatine in the diet for 28 d); creatine overload plus diet with creatine group (CrO + D; 5 g creatine/kg by oral administration for 5 d + 2 % in the diet for 23 d). Plasma Hcy was significantly lower (P<0.05) in DCr (7.5 (SD 1.2) mu mol/l) and CrO + D (7.2 (SD 1.7) mu mol/l) groups compared with the control group (12.4 (SD 2.2) mu mol/l). Both plasma thiobarbituric acid-reactive species (TBARS) (control, 10 (SD 3.4); DCr, 4.9 (So 0.7); CrO + D, 2.4 (SD 1) mu mol/l) and plasma total glutathione (control, 4.3 (SD 1.9); DCr, 2.5 (SD 0.8); CrO + D, 1.8 (SD 0.5) mu mol/l) were lower in the groups that received creatine (P<0.05). In addition, Hcy showed significant negative correlation (P<0.05) with plasma creatine (r - 0.61) and positive correlation with plasma TBARS (r 0.74). Plasma creatine was negatively correlated with plasma TBARS (r - 0.75) and total peroxide (r - 0.40). We conclude that creatine supplementation reduces plasma Hcy levels and lipid peroxidation biomarkers, suggesting a protective role against oxidative damage. Modulating Hcy fort-nation may, however, influence glutathione synthesis and thereby affect the redox state of the cells.

Effects of a Low-Protein Diet on Plasma Amino Acid and Homocysteine Levels and Oxidative Status in Rats

Background/Aims: Transmethylation reactions and antioxidant metabolism are linked by transsulfuration, where homocysteine (Hcy) is converted to cysteine and reduced glutathione (GSH). Low protein intake can modulate the balance of this metabolic reaction. The aim of the present investigation was to study the effect of a low-protein diet on Hcy metabolism by monitoring levels of the amino acids involved in these pathways, and relating these levels to GSH levels and lipid peroxidation in rats. Methods: Sixteen rats were divided into 2 groups: control (C; standard AIN-93 diet, 20% protein) and low-protein diet (LPD; 8% protein diet). Rats in both groups were placed on the diets for 28 days. Results: A significant reduction (p < 0.05) in plasma Hcy concentration was found in LPD rats (0.16 +/- 0.04 mu mol/mg protein) versus C rats (0.25 +/- 0.03 mu mol/mg protein). Methionine levels were not significantly different between the 2 groups (C: 1.24 +/- 0.22 mu mol/mg protein; LPD: 1.03 +/- 0.27 mu mol/mg protein). A significant reduction (p ! 0.05) in hepatic GSH concentrations (C: 44 8 10 mu mol/mg protein; LPD: 17.4 +/- 4.3 mu mol/mg protein) was accompanied by an increase in lipid peroxidation (C: 0.13 +/- 0.01 mu mol/mg protein; LPD: 0.17 +/- 0.02 mu mol/mg protein; r = -0.62, p < 0.01). Conclusion: Hcy levels were reduced under a low-protein diet, resulting in modulated methyl balance and reduced GSH formation leading to increased susceptibility of hepatic cells to oxidative events. Copyright (C) 2009 S. Karger AG, Basel

Cross-reactive IgE antibody responses to tropomyosins from Ascaris lumbricoides and cockroach

Background: Evidence indicates that infection with Ascaris lumbricoides may promote development of allergy and asthma. Objective: To study the role of tropomyosin, a pan-allergen in invertebrates, in IgE responses to A lumbricoides. Methods: Recombinant A lumbricoides and Periplaneta americana tropomyosins were expressed in Pichia pastoris. Levels of IgE to tropomyosins from A lumbricoides and P americana were determined by chimeric ELISA in sera from 119 children living in a parasite-endemic area and 112 patients with cockroach allergy from the allergy clinics. Presence of tropomyosin in A lumbricoides larvae at L3 stage was evaluated by immunofluorescence using mAb IA6, directed against mite tropomyosin. Molecular modeling of P americana and A lumbricoides tropomyosins was performed by using the MODELLER program. Results: A lumbricoides tropomyosin showed 69% to 98% sequence identity to tropomyosins from other invertebrates. The predicted structure of A lumbricoides tropomyosin was similar to that of P americana tropomyosin and showed the characteristic coiled-coil structure. Strong correlation was found for IgE antibodies to tropomyosins from A lumbricoides and P americana in sera from children living in a parasite-endemic area and from patients with cockroach allergy. Larvae of A lumbricoides reacted strongly with mAb IA6. Conclusion: Tropomyosin induces IgE responses in A lumbricoides-infected children and in patients allergic to cockroach.

Discordant Nadir GH After Oral Glucose and IGF-I Levels on Treated Acromegaly: Refining the Biochemical Markers of Mild Disease Activity

Biochemical markers for remission on acromegaly activity are controversial. We studied a subset of treated acromegalic patients with discordant nadir GH levels after oral glucose tolerance test (oGTT) and IGF-I values to refine the current consensus on acromegaly remission. We also compared GH results by two GH immunoassays. From a cohort of 75 treated acromegalic patients, we studied 13 patients who presented an elevated IGF-I despite post-oGTT nadir GH of <= 1 mu g/l. The 12-h daytime GH profile (GH-12 h), nadir GH after oGTT, and basal IGF-I levels were studied in patients and controls. Bland-Altman method showed high concordance between GH assays. Acromegalic patients showed higher mean GH-12 h values (0.71+/-0.36 vs. 0.31+/-0.28 mu g/l; p<0.05) and nadir GH after oGTT (0.48+/-0.32 vs. 0.097+/-0.002 mu g/l; p<0.05) as compared to controls. Nadir GH correlated with mean GH-12 h (r=0.92, p<0.05). The mean GH-12 h value from upper 95% CI of controls (0.54 mu g/l) would correspond to a theoretical normal nadir GH of <= 0.27 mu g/l. Patients with GH nadir <= 0.3 mu g/l had IGF-I between 100-130% ULNR (percentage of upper limit of normal range) and mean GH-12 h of 0.35+/-0.15, and patients with GH nadir >0.3 and <= 1 mu g/l had IGF-I >130% ULNR and mean GH-12 h of 0.93+/-0.24 mu g/l. Our data integrate daytime GH secretion, nadir GH after oGTT, and plasma IGF-I concentrations showing a continuum of mild residual activity in a subgroup of treated acromegaly with nadir GH values <= 1 mu g/l. The degree of increased IGF-I levels and nadir GH after oGTT are correlated with the subtle abnormalities of daytime GH secretion.