Collagen V and vascular injury promote lung architectural changes in systemic sclerosis

Background: Systemic sclerosis (SSc) is a multisystem disorder characterized by inflammation, fibrosis and vascular damage. The aim of this study was to evaluate the interactions between basement membrane disruption, endothelial injury and collagen V deposition on the vascular wall, as well as their association with pulmonary function tests in patients with SSc. Method: The endothelial apoptosis was assessed by TUNEL and electron microscopy, and quantified through the point-counting technique. To evaluate basement membrane integrity, laminin immunostaining and electron microscopy were used. Immunofluorescence and morphometric analysis were used to determine the amount of collagen V in the vascular walls in 23 open lung biopsies of patients with SSc without pulmonary hypertension. Normal lung tissue was obtained from five individuals who had died of traumatic injuries. Results: The apoptosis index in SSc was higher in the endothelial cells (13.83 +/- 6.83) when compared with the control (2.51 +/- 2.06) group (P < 0.001) and confirmed by electron microscopy. We observed an important disruption of the basement membrane on the vascular wall shown by discontinuous laminin immunostaining and electron microscopy. An increase in collagen V on the vascular wall of the SSc group was observed (45.28 +/- 13.21), when compared with control group (22.90 +/- 4.13, P < 0.001), and this difference was statistically significant. An inverse correlation was found between vital capacity, forced vital capacity, forced expiratory volume in 1 s, vascular collagen V and endothelial apoptosis (P < 0.05). Conclusions: We conclude that the endothelial apoptosis and vascular collagen V interaction reinforce the vascular pathway in the SSc pathogenesis. Further studies are needed to determine whether this relationship is causal or consequential. Please cite this paper as: Parra ER, Aguiar AC Jr, Teodoro WR, de Souza R, Yoshinari NH and Capelozzi VL. Collagen V and vascular injury promote lung architectural changes in systemic sclerosis. The Clinical Respiratory Journal 2009; 3: 135-142.

Inducible nitric oxide synthase inhibition attenuates lung tissue responsiveness and remodeling in a model of chronic pulmonary inflammation in guinea pigs

We evaluated the influence of iNOS-derived NO on the mechanics, inflammatory, and remodeling process in peripheral lung parenchyma of guinea pigs with chronic pulmonary allergic inflammation. Animals treated or not with 1400W were submitted to seven exposures of ovalbumin in increasing doses. Seventy-two hours after the 7th inhalation, lung strips were suspended in a Krebs organ bath, and tissue resistance and elastance measured at baseline and after ovalbumin challenge. The strips were submitted to histopathological measurements. The ovalbumin-exposed animals showed increased maximal responses of resistance and elastance (p < 0.05), eosinophils counting (p < 0.001), iNOS-positive cells (p < 0.001), collagen and elastic fiber deposition (p < 0.05), actin density (p < 0.05) and 8-iso-PGF2 alpha expression (p < 0.001) in alveolar septa compared to saline-exposed ones. Ovalbumin-exposed animals treated with 1400 W had a significant reduction in lung functional and histopathological findings (p < 0.05). We showed that iNOS-specific inhibition attenuates lung parenchyma constriction, inflammation, and remodeling, suggesting NO-participation in the modulation of the oxidative stress pathway. (C) 2008 Elsevier B.V. All rights reserved.

Effects of different mechanical ventilation strategies on the mucociliary system

To evaluate the effects of different mechanical ventilation (MV) strategies on the mucociliary system. Experimental study. Twenty-seven male New Zealand rabbits. After anesthesia, animals were tracheotomized and ventilated with standard ventilation [tidal volume (Vt) 8 ml/kg, positive end expiratory pressure (PEEP) 5 cmH(2)O, flow 3 L/min, FiO(2) 0.4] for 30 min. Next, animals were randomized into three groups and ventilated for 3 h with low volume (LV): Vt 8 ml/kg, PEEP 5 cmH(2)O, flow 3 L/min (n = 6); high volume (HV): Vt 16 ml/kg, PEEP 5 cmH(2)O, flow 5 L/min (n = 7); or high pressure (HP): Ppeak 30 cmH(2)O, PEEP 12 cmH(2)O (n = 8). Six animals (controls) were ventilated for 10 min with standard ventilation. Vital signals, blood lactate, and respiratory system mechanics were verified. Tracheal tissue was collected before and after MV. Lung and tracheal tissue sections were stained to analyze inflammation and mucosubstances by the point-counting method. Electron microscopy verified tracheal cell ultrastructure. In situ tracheal ciliary beating frequency (CBF), determined using a videoscopic technique, and tracheal mucociliary transport (TMCT), assessed by stereoscopic microscope, were evaluated before and after MV. Respiratory compliance decreased in the HP group. The HV and HP groups showed higher lactate levels after MV. Macroscopy showed areas of atelectasis and congestion on HV and HP lungs. Lung inflammatory infiltrate increased in all ventilated groups. Compared to the control, ventilated animals also showed a reduction of total and acid mucus on tracheal epithelium. Under electron microscopy, injury was observed in the ciliated cells of the HP group. CBF decreased significantly after MV only in the HP group. TMCT did not change significantly in the ventilated groups. Different MV strategies induce not only distal lung alterations but also morphological and physiological tracheal alterations leading to mucociliary system dysfunction.

Pleural fluid cytokines correlate with tissue inflammatory expression in tuberculosis

SETTING: A tertiary care research centre in Sao Paolo, Brazil. OBJECTIVE: To quantify interleukin (IL) 8, tumour necrosis factor alpha (TNF-alpha), vascular endothelial growth factor (VEGF) and transforming growth factor beta(1), (TGF-beta(1))in pleural fluid from tuberculous patients, correlating its values with the histopathological patterns in pleural biopsies. DESIGN: Cytokines were quantified in patients with transudatcs secondary to congestive heart failure (n = 8) and exudates secondary to tuberculosis (TB; n = 39). In parietal pleural biopsies from TB patients, the histological patterns of the inflammatory response were quantified by morphometric analysis (stereological point-counting method). RESULTS: IL-8, TNF-alpha, VEGF and TGF-beta(1) levels were higher in TB than in transudates. A positive correlation existed between components of the fibrinoid exudative phase with pleural fluid IL-8 (R = 0.52, P = 0.004) and VEGF (R = 0.42, P = 0.0021) levels. A negative correlation existed between pleural fluid IL-8 (R = -0.37, P = 0.048) and VEGF (R = -0.44, P = 0.0015) levels with tissue components of fibroproliferation. CONCLUSION: The high pleural levels of TNF-a, IL-8, VEGF and TGF-beta(1) suggest the involvement of these cytokines in the TB immunological response. The positive correlation between pleural fluid IL-8 and VEGF with the components of the acute exudative phase and the negative correlation between these cytokines with the fibroproliferative components suggest a temporary inflammatory response in the pleural space.

Changes of somatomotor and parietal regions produced by different amounts of electrical stimulation

Our study aims to investigate changes in electrocortical activity by observing the variations in absolute theta power in the primary somatomotor and parietal regions of the brain under three different electrical stimulation conditions: control group (without stimulation), group 24 (24 trials of stimulation) and group 36 (36 trials of stimulation). Thus, our hypothesis is that the application of different patterns of electrical stimulation will promote different states of habituation in these regions. The sample was composed of 24 healthy (absence of mental and physical impairments) students (14 male and 10 female), with ages varying from 25 to 40 years old (32.5 +/- 7.5), who are right-handed (Edinburgh Inventory). The subjects were randomly distributed into three groups: control (n = 8), G24 (n = 8) and G36 (n = 8). We use the Functional electrical stimulation (FES) equipment (NeuroCompact-2462) to stimulate the right index finger extensor muscle, while the electroencephalographic signal was simultaneously recorded. We found an interaction between condition and block factors for the C3 and P3 electrode, a condition and block main effects for the C4 electrode, and a condition main effect for the P4 electrode. Our results support the hypothesis that electrical stimulation promotes neurophysiological changes. It appears that stimulus adaptation (accommodation) of specific circuits can strengthen the brain`s ability to distinguish between and respond to such stimuli over time. (C) 2009 Elsevier Ireland Ltd. All rights reserved.

Topical interleukin-1 receptor antagonist inhibits inflammatory cell infiltration into the cornea

Interleukin (IL)-1 alpha and beta are important modulators of many functions of corneal epithelial and stromal cells that occur following injury to the cornea, including the influx of bone marrow-derived inflammatory cells into the stroma attracted by chemokines released from the stroma and epithelium. In this study, we examined the effect of topical soluble IL-1 receptor antagonist on bone marrow-derived cell influx following corneal epithelial scrape injury in a mouse model. C57BL/6 mice underwent corneal epithelial scrape followed by application of IL-1 receptor antagonist (Amgen, Thousand Oaks, CA) at a concentration of 20 mg/ml or vehicle for 24 h prior to immunocytochemical detection of marker CD11b-positive cells into the stroma. In two experiments, topical IL-1 receptor antagonist had a marked effect in blocking cell influx. For example, in experiment 1, topical IL-1 receptor antagonist markedly reduced detectible CD11b-positive cells into the corneal stroma at 24 It after epithelial injury compared with the vehicle control (3.5 +/- 0.5 (standard error of the mean) cells/400x field and 13.9 +/- 1.2 cells/400x field, respectively, p < 0.01). A second experiment with a different observer performing cell counting had the same result. Thus, the data demonstrate conclusively that topical IL-1 receptor antagonist markedly down-regulates CD-11b-positive monocytic cell appearance in the corneal stroma. Topical IL-1 receptor antagonist could be an effective adjuvant for clinical treatment of corneal conditions in which unwanted inflammation has a role in the pathophysiology of the disorder. (c) 2008 Elsevier Ltd. All rights reserved.

A combined study of behavior and Fos expression in limbic structures after re-testing Wistar rats in the elevated plus-maze

The elevated plus-maze is an animal model used to study anxiety. In a second session, rats show a reduction in the exploratory behavior even when the two sessions are separated by intervals as large as 7 days. The aim of the present study was to investigate whether the reduction in the exploratory behavior is maintained after intervals larger than 7 days. Additionally, we aimed at investigating eventual correlations between behaviors in the plus-maze and activation of limbic structures as measured by Fos protein expression after the second session. Rats were tested for 5 min in the elevated plus-maze and re-tested 3, 9 or 33 days later. Other groups were tested only once. The rat brains were processed for immunohistochemical detection of Fos protein. The results show a decrease in the open arms exploration in the second trial with intervals of 3, 9 and 33 days. The expression of Fos protein in the piriform cortex, septal nucleus and paraventricular hypothalamic nucleus in the groups tested with intervals of 9 and 33 days were statistically different from the other groups. The alterations observed in exploratory behavior in the second session in the plus-maze did not correlate with Fos expression. In conclusion, although the specific test conditions were sufficient to evoke behavioral alterations in exploration in the elevated plus-maze, they were enough to induce significant Fos protein expression in piriform cortex, septal nucleus and thalamic and hypothalamic paraventricular nuclei but not in other areas such as dorsomedial nucleus of the hypothalamus and amygdala nuclei, known to be also active participants in circuits controlling fear and anxiety. (C) 2010 Elsevier Inc. All rights reserved.

Activation of lateral parabrachial afferent pathways and endocrine responses during sodium appetite regulation

Modulation of salt appetite involves interactions between the circumventricular organs (CVOs) receptive areas and inhibitory hindbrain serotonergic circuits. Recent studies provide support to the idea that the serotonin action in the lateral parabrachial nucleus (LPBN) plays an important inhibitory role in the modulation of sodium appetite. The aim of the present work was to identify the specific groups of neurons projecting to the LPBN that are activated in the course of sodium appetite regulation, and to analyze the associated endocrine response, specifically oxytocin (OT) and atrial natriuretic peptide (ANP) plasma release, since both hormones have been implicated in the regulatory response to fluid reestablishment. For this purpose we combined the detection of a retrograde transported dye, Fluorogold (FG) injected into the LPBN with the analysis of the Fos immunocytochemistry brain pattern after sodium intake induced by sodium depletion. We analyzed the Fos-FG immunoreactivity after sodium ingestion induced by peritoneal dialysis (PD). We also determined OT and ANP plasma concentration by radioimmunoassay (RIE) before and after sodium intake stimulated by PD. The present study identifies specific groups of neurons along the paraventricular nucleus, central extended amygdala, insular cortex, dorsal raphe nucleus, nucleus of the solitary tract and the CVOs that are activated during the modulation of sodium appetite and have direct connections with the LPBN. It also shows that OT and ANP are released during the course of sodium satiety and fluid reestablishment. The result of this brain network activity may enable appropriate responses that re-establish the body fluid balance after induced sodium consumption. (C) 2009 Elsevier Inc. All rights reserved.

Multi-system neurological disease is common in patients with OPA1 mutations

Additional neurological features have recently been described in seven families transmitting pathogenic mutations in OPA1, the most common cause of autosomal dominant optic atrophy. However, the frequency of these syndromal `dominant optic atrophy plus` variants and the extent of neurological involvement have not been established. In this large multi-centre study of 104 patients from 45 independent families, including 60 new cases, we show that extra-ocular neurological complications are common in OPA1 disease, and affect up to 20% of all mutational carriers. Bilateral sensorineural deafness beginning in late childhood and early adulthood was a prominent manifestation, followed by a combination of ataxia, myopathy, peripheral neuropathy and progressive external ophthalmoplegia from the third decade of life onwards. We also identified novel clinical presentations with spastic paraparesis mimicking hereditary spastic paraplegia, and a multiple sclerosis-like illness. In contrast to initial reports, multi-system neurological disease was associated with all mutational subtypes, although there was an increased risk with missense mutations [odds ratio = 3.06, 95% confidence interval = 1.44-6.49; P = 0.0027], and mutations located within the guanosine triphosphate-ase region (odds ratio = 2.29, 95% confidence interval = 1.08-4.82; P = 0.0271). Histochemical and molecular characterization of skeletal muscle biopsies revealed the presence of cytochrome c oxidase-deficient fibres and multiple mitochondrial DNA deletions in the majority of patients harbouring OPA1 mutations, even in those with isolated optic nerve involvement. However, the cytochrome c oxidase-deficient load was over four times higher in the dominant optic atrophy + group compared to the pure optic neuropathy group, implicating a causal role for these secondary mitochondrial DNA defects in disease pathophysiology. Individuals with dominant optic atrophy plus phenotypes also had significantly worse visual outcomes, and careful surveillance is therefore mandatory to optimize the detection and management of neurological disability in a group of patients who already have significant visual impairment.

Intraoperative bleeding during vitrectomy for diabetic tractional retinal detachment with versus without preoperative intravitreal bevacizumab (IBeTra study)

Aims: To compare the amount of intraoperative intraocular bleeding in patients with diabetes with macula-involving tractional retinal detachment (TRD) undergoing pars plana vitrectomy (PPV) with and without preoperative intravitreal bevacizumab (IVB) injection. Methods: An institutional study was carried out with consecutive patients with diabetic retinopathy and macula-involving TRD of recent (3 months) onset who were randomly assigned to PPV only (PPV group) or PPV combined with one IVB (1.5 mg/0.06 ml) injection 2 weeks prior to surgery (bevacizumab (BEV)/PPV group). All patients underwent 23-gauge PPV 3 weeks after baseline. The main outcome measure was erythrocyte count in the fluid retrieved from the vitrectomy cassette using a Neubauer counting chamber. Results: The study included 20 patients. The mean erythrocyte count was 14865x10(3) (SD 19332x10(3); median 4500x10(3)) cells in the BEV/PPV group, and 176240x10(3) (SD 108375x10(3); median 166600x10(3)) cells in the PPV group. The mean erythrocyte count was significantly lower in the BEV/PPV group than in the PPV group (p < 0.0001). No major adverse events were identified. Conclusion: Preoperative IVB injection was associated with reduced intraocular bleeding during 23-gauge PPV for diabetic macula-involving TRD. Further studies are needed to confirm our preliminary findings.

Inflammatory mediators involved in the nociceptive and oedematogenic responses induced by Tityus serrulatus scorpion venom injected into rat paws.

The present study investigated the role of kinins, prostaglandins (PGs) and nitric oxide (NO) in mechanical hypernociception, Spontaneous nociception and paw oedema after intraplantar (ipl) injection of Tityus serrulatus venom (Tsv) in male Wistar rats. Tsv was ipl-injected in doses of 0.01-10 mu g/paw. Pre-treatment (30 min prior) with DALBK (100 nmol/paw) and icatibant (10 nmol/paw), B1 and B2 selective kinin receptor antagonists, L-NAME (50 mg/kg, i.p., a non-selective nitric oxide synthase inhibitor) or celecoxib, selective COX-2 inhibitor, was given 1 h prior per os (5 mg/kg, p.o.), significantly reduced the hypernociceptive response (Von Frey method), the spontaneous nociception (determined by counting the number of flinches) and paw oedema (plethysmometer method) induced by Tsv at doses of 1.0 and 10 mu g/paw for both nociceptive and oedematogenic responses, respectively. Nevertheless, indomethacin (5 mg/kg, i.p.. 30 min prior) was ineffective in altering all of these events. The results of the present study show that Tsv, injected ipl into the rat paw, causes a dose-dependent paw oedema, mechanical hypernociception and flinches (a characteristic biphasic response) in which kinins and NO are substantially involved. Although celecoxib was effective against the oedema and pain caused by Tsv, COX-2 does not seem to be involved in the inflammatory response caused by Tsv. (C) 2008 Elsevier Ltd. All rights reserved.

Is dystonic posturing during temporal lobe epileptic seizures the expression of an endogenous anticonvulsant system?

In temporal lobe epilepsy (TLE) seizures, tonic or clonic motor behaviors (TCB) are commonly associated with automatisms, versions, and vocalizations, and frequently occur during secondary generalization. Dystonias are a common finding and appear to be associated with automatisms and head deviation, but have never been directly linked to generalized tonic or clonic behaviors. The objective of the present study was to assess whether dystonias and TCB are coupled in the same seizure or are associated in an antagonistic and exclusive pattern. Ninety-one seizures in 55 patients with TLE due to mesial temporal sclerosis were analyzed. Only patients with postsurgical seizure outcome of Engel class I or II were included. Presence or absence of dystonia and secondary generalization was recorded. Occurrence of dystonia and occurrence of bilateral tonic or clonic behaviors were negatively correlated. Dystonia and TCB may be implicated in exclusive, non-coincidental, or even antagonistic effects or phenomena in TLE seizures. A neural network related to the expression of one behavioral response (e.g., basal ganglia activation and dystonia) might theoretically ""displace"" brain activation or disrupt the synchronism of another network implicated in pathological circuit reverberation and seizure expression. The involvement of basal ganglia in the blockade of convulsive seizures has long been observed in animal models. The question is: Do dystonia and underlying basal ganglia activation represent an attempt of the brain to block imminent secondary generalization? (C) 2007 Elsevier Inc. All rights reserved.

Shape alterations in the striatum in chorea-acanthocytosis

Chorea-acanthocytosis (ChAc) is an uncommon autosomal recessive disorder due to mutations of the VPS13A gene, which encodes for the membrane protein chorein. ChAc presents with progressive limb and orobuccal chorea, but there is often a marked dysexecutive syndrome. ChAc may first present with neuropsychiatric disturbance such as obsessive-compulsive disorder (OCD), suggesting a particular role for disruption to striatal structures involved in non-motor frontostriatal loops, such as the head of the caudate nucleus. Two previous studies have suggested a marked reduction in volume in the caudate nucleus and putamen, but did not examine morphometric change. We investigated morphometric change in 13 patients with genetically or biochemically confirmed ChAc and 26 age- and gender-matched controls. Subjects underwent magnetic resonance imaging and manual segmentation of the caudate nucleus and putamen, and shape analysis using a non-parametric spherical harmonic technique. Both structures showed significant and marked reductions in volume compared with controls, with reduction greatest in the caudate nucleus. Both structures showed significant shape differences, particularly in the head of the caudate nucleus. No significant correlation was shown between duration of illness and striatal volume or shape, suggesting that much structural change may have already taken place at the time of symptom onset. Our results suggest that striatal neuron loss may occur early in the disease process, and follows a dorsal-ventral gradient that may correlate with early neuropsychiatric and cognitive presentations of the disease. (C) 2010 Elsevier Ireland Ltd. All rights reserved.

Insulin Affects Tissue Organization and the Kinetics of Epithelial Cell Death in the Rat Ventral Prostate After Castration

Prostate growth and physiology are regulated by steroid hormones and modulated by multiple endocrine factors We investigated the action of insulin on the tissue organization and kinetics of epithelial cells in the rat ventral prostate (VP) in response to castration up to 120 hours after surgery by using an acute protocol of alloxan induced diabetes Diabetes caused a reduction in volume density (Vv(o)/) and volume of the epithelium The effects of castration on the epithelium were accelerated in the diabetic animals as determined by changes in V(o)/, and volume The smooth muscle cells became atrophic and apparently relaxed in response to castration in contrast to the spinous aspect observed in nondiabetic castrated rats Counting of apoptotic nuclei in the epithelium showed the classical apoptosis peak at 72 hours in nondiabetic rats and an advance of the apoptosis peak to 48 hours after castration in diabetic rats Insulin restored the time of the peak to 72 hours These results were confirmed after immunostaining for cleaved caspase 3 and suggest a survival and antiapoptotic effect on VP epithelial cells in both the presence and absence of androgen stimulation This idea is supported by the observation that insulin also reduced the overall rate of apoptosis at all experimental points analyzed before and after castration

The essential role of toll like receptor-4 in the control of Aggregatibacter actinomycetemcomitans infection in mice

Objective: Aggregatibacter actinomycetemcomitans is an oral Gram-negative bacterium that contributes to periodontitis progression. Isolated antigens from A. actinomycetemcomitans could be activating innate immune cells through Toll-like receptors (TLRs). In this study, we evaluated the role of TLR4 in the control of A. actinomycetemcomitans infection. Material and Methods: We examined the mechanisms that modulate the outcome of A. actinomycetemcomitans-induced periodontal disease in TLR4(-/-) mice. The production of cytokines was evaluated by ELISA. The bacterial load was determined by counting the number of colony-forming units per gram of tissue. Results: The results showed that TLR4-deficient mice developed less severe periodontitis after A. actinomycetemcomitans infection, characterized by significantly lower bone loss and inflammatory cell migration to periodontal tissues. However, the absence of TLR4 facilitated the A. actinomycetemcomitans dissemination. Myeloperoxidase activity was diminished in the periodontal tissue of TLR4(-/-) mice. We observed a significant reduction in the production of tumour necrosis factor-alpha (TNF-alpha) and interleukin (IL)-1 beta in the periodontal tissue of TLR4(-/-) mice. Conclusion: The results of this study highlighted the role of TLR4 in controlling A. actinomycetemcomitans infection.