Gasless fetoscopy: A new approach to endoscopic closure of a lumbar skin defect in fetal sheep

Objective: To develop a new endoscopic approach to the correction of a myelomeningocele-like defect in fetal sheep. Methods: The fetuses of 9 pregnant ewes, with an average gestational age of 115 days, were subjected to a 3.0 x 2.0 cm removal of the skin over the lumbar spine, performed through hysterotomy. The uterus was closed, and three 5-mm endoscopic cannulas, without valve mechanisms, were inserted. In the pilot phase (2 animals), we initially worked exclusively in the amniotic fluid space. In the study phase, we partially withdrew the fetus from the amniotic fluid to completely expose its back. By simply allowing air to enter the amniotic cavity (without gas injection), a working space was created using a uterine lift device. The skin around the defect was dissected, and a biosynthetic cellulose material was applied to cover the area. A continuous suture of the skin was performed to completely hide the material. Results: The combined air/fluid space allowed the skin to be successfully closed in 6 out of 7 cases in the study phase. All fetuses were alive at the end of the procedures. Time to complete the endoscopic part of the procedure fell from 3 to 1 h by the end of this series. Premature birth occurred in 2 of the 4 cases allowed to continue with the pregnancy. Conclusion: A new gasless fetoscopic surgery technique was developed as an alternative to current techniques used for fetal endoscopic surgery. Copyright (C) 2008 S. Karger AG, Basel.

Crotamine toxicity and efficacy in mouse models of melanoma

Objectives: Selective anticancer cell activity for both cell-penetrating and cationic antimicrobial peptides has previously been reported. As crotamine possesses activities similar to both of these, this study investigates crotamine`s anticancer toxicity in vitro and in vivo. Research design and methods: In vitro cancer cell viability was evaluated after treatment with 1 and 5 mu g/ml of crotamine. In vivo crotamine cytotoxic effects in C57Bl/6J mice bearing B16-F10 primary cutaneous melanoma were tested, with two groups each containing 35 mice. The crotamine-treated group received 1 mu g/day of crotamine per animal, subcutaneously which was well tolerated; the untreated group received a placebo. Results: Crotamine at 5 mu g/ml was lethal to B16-F10, Mia PaCa-2 and SK-Mel-28 cells and inoffensive to normal cells. In vivo crotamine treatment over 21 days significantly delayed tumor implantation, inhibited tumor growth and prolonged the lifespan of the mice. Mice in the crotamine-treated group survived at significantly higher rates (n = 30/35) than those in the untreated group (n = 7/35) (significance calculated with the Kaplan-Meier estimator). The average tumor weight in the untreated group was 4.60 g but was only about 0.27 g in the crotamine-treated mice, if detectable. Conclusions: These data warrant further exploration of crotamine as a tumor inhibition compound.

Comparison of Two Models for Evaluation Histopathology of Experimental Renal Ischemia

Renal ischemia/reperfusion (I/R) injury is one of the frequent causes of acute renal failure (ARF) due to the complex, interrelated sequence of events, that result in damage to and death of kidney cells. Cells of the proximal tubular epithelium are especially susceptible to I/R injury, leading to acute tubular necrosis, which plays a pivotal role in the pathogenesis of ARE Several models have been explicated to assess morphological changes, including those of Jabonski et al. and Goujon et al. We compared the 2 models for histopathological evaluation of 30- or 120-minute periods of renal ischemia followed by 24-hour reperfusion in rats. Several changes were observed after application of the 2 models: proximal tubular cell necrosis, loss of brush border, vacuolization, denudation of tubular basement membrane as a consequence of flattening of basal cells, and presence of intratubular exfoliated cells in the lumen of proximal convoluted tubules at various stages of degeneration (karyorexis, kariopyknosis and karyolysis). Evaluating tubular lesions after 2 periods of experimental ischemia with light microscopy allowed us to conclude that the Goujon classification better characterized the main changes in cortical renal tubules after ischemia.

EFFECT OF FLUID AND FOOD INTAKE ON THE BODY COMPOSITION EVALUATION OF ELDERLY PERSONS

Background: Several studies have shown that liquid and food intake interfere with the evaluation of body composition in adults. However, since there are no reports about this interference in the elderly population, the need to fast for this evaluation may be dispensable. Objectives: The objective of the present study was to assess the influence of liquid and solid food on the measurement of body composition by bioelectrical impedance analysis (BIA) and by dual energy X-ray absorptiometry (DXA). Design: Forty-one male volunteers aged 62 to 87 years participated in the study. The subjects were submitted to evaluation of body composition by DXA and BIA under fasting conditions and 1 hour after the ingestion of breakfast (500 ml of orange juice and one 50 g bread roll with butter). Results: There was no significant difference in the variables fat-free mass (FFM) or fat mass (FM) between the fasting condition and the evaluation performed 1 hour after the meal as measured by BIA or DXA. There was also no significant difference when the same variables were compared between methods. Conclusion: In the present study, the ingestion of 500 ml orange juice and of one bread roll with butter by elderly subjects did not affect the results of the parameters of body composition determined by BIA or DXA. Thus, these exams could be performed without the rigor of fasting, often poorly tolerated by the elderly.

Protective Effect of RC-3095, an Antagonist of the Gastrin-Releasing Peptide Receptor, in Experimental Arthritis

Objective. To evaluate the antiinflammatory effects of RC-3095 in 2 experimental models of arthritis, collagen-induced arthritis (CIA) and antigen-induced arthritis (AIA), and to determine the mechanisms of action involved. Methods. RC-3095 was administered daily to mice with CIA and mice with AIA, after induction of disease with methylated bovine serum albumin. Disease incidence and severity were assessed using a clinical index and evaluation of histologic features, respectively. In mice with CIA, gastrin-releasing peptide receptor (GRPR) was detected by immunohistochemical analysis, while in mice with AIA, migration of neutrophils, presence of glycosaminoglycans, and lymphocyte proliferation, determined using the MTT assay, were assessed. Expression of cytokines interleukin-17 (IL-17), IL-1 beta, and tumor necrosis factor alpha (TNF alpha) was evaluated in all mouse knees using enzyme-linked immunosorbent assay. Treg cell production was assessed by flow cytometry in the joints of mice with AIA. Results. In mice with AIA, administration of RC-3095 reduced neutrophil migration, mechanical hypernociception, and proteoglycan loss. These findings were associated with inhibition of the levels of all 3 proinflammatory cytokines, decreased lymphocyte proliferation, and increased Treg cell numbers. In the CIA model, treatment with RC-3095 led to a significant reduction in arthritis clinical scores and the severity of disease determined histologically. Synovial inflammation, synovial hyperplasia, pannus formation, and extensive erosive changes were all dramatically reduced in the arthritic mice treated with RC-3095. Furthermore, arthritic mice treated with RC-3095 showed a significant reduction in the concentrations of IL-17, IL-1 beta, and TNF alpha, and showed a diminished expression of GRPR. Conclusion. These findings suggest that the GRP pathway has a significant role in chronic arthritis, and its inhibition can be explored as a possible therapeutic strategy in rheumatoid arthritis.

Anti-aversive effects of the atypical antipsychotic, aripiprazole, in animal models of anxiety

Aripiprazole is a unique antipsychotic that seems to act as a partial agonist at dopamine D2-receptors, contrasting with other drugs in this class, which are silent antagonists. Aripiprazole may also bind to serotonin receptors. Both neurotransmitters may play major roles in aversion-, anxiety-and panic-related behaviours. Thus, the present work tested the hypothesis that this antipsychotic could also have anti-aversive properties. Male Wistar rats received injections of aripiprazole (0.1-10 mg/kg) and were tested in the open field, in the elevated plus and T mazes (EPM and ETM, respectively) and in a contextual fear conditioning paradigm. Aripiprazole (1mg/kg) increased the percentage of entries onto the open arms of the EPM and attenuated escape responses in the ETM. In the latter model, the dose of 0.1 mg/kg also decreased the latency to leave the enclosed arm, suggesting anxiolytic- and panicolytic-like properties. This dose also decreased the time spent in freezing in a contextual fear conditioning. No significant motor effects were observed at these doses. The present data support the hypothesis that aripiprazole could inhibit anxiety-related responses. Acting as a partial agonist at dopamine receptors, this drug could effectively treat schizophrenia and, in contrast with most antipsychotic drugs, alleviate aversive states.

Anxiolytic-like effect of noradrenaline microinjection into the dorsal periaqueductal gray of rats

The brain noradrenergic system has been implicated in the expression of defensive behaviors elicited by acute stress. The dorsal periaqueductal gray area (dPAG) is a key structure involved in the behavioral and cardiovascular responses elicited by fear and anxiety situations. Although there are noradrenergic terminals in the dPAG, few studies have investigated the role of noradrenaline (NA) in the dPAG on anxiety modulation. The aim of this study was to evaluate the effect of NA microinjection into the dPAG of rats subjected to two animal models of anxiety, the elevated plus-maze and the Vogel conflict test. Male Wistar rats implanted with a guide cannula aimed at the dPAG received microinjections of NA (3, 15, or 45 nmol/0.05 mu l) or artificial cerebral spinal fluid into the dPAG immediately before being exposed to the elevated plus-maze or the Vogel conflict test. NA increased the exploration of the open arms and the number of enclosed arm entries in the elevated plus-maze. The increase in open arm exploration remained significant after being subjected to an analysis of covariance using the latter variable as covariate. Moreover, the NA microinjection into the dPAG did not increase general exploratory activity of animals subjected to the open-field test, indicating that the increase in open arm exploration cannot be attributed to a nonspecific increase in exploratory activity. In the Vogel test, the NA microinjection into the dPAG increased the number of punished licks without changing the number of nonpunished licks or interfering with the tail-flick test. The results, therefore, indicate that the NA microinjection into the dPAG produces anxiolytic-like effects, suggesting its possible involvement in the anxiety modulation. Behavioural Pharmacology 20:252-259 (C) 2009 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins.

Protective effect of an extract from Ascaris suum in experimental arthritis models

We investigated the effect of an extract from a helminth (Ascaris suum) in zymosan-induced arthritis (ZYA) or collagen-induced arthritis (CIA). Rats and mice, respectively, received 1 mg and 0.1 mg zymosan intra-articularly (i.a.). Test groups received an A. suum extract either per os (p.o.) or intraperitoneally (i.p.) 30 min prior to i.a. zymosan. Controls received saline. Hypernociception was measured using the articular incapacitation test. Cell influx, nitrite, and cytokine levels were assessed in joint exudates. The synovia and distal femoral extremities were used for histopathology. Cartilage damage was assessed through determining glycosaminoglycan (GAG) content. DBA/1J mice were subjected to CIA. The test group received A. suum extract i.p. 1 day after CIA became clinically detectable. Clinical severity and hypernociception were assessed daily. Neutrophil influx was determined using myeloperoxidase activity. The A. suum extract, either i.p. or p.o., significantly and dose-dependently inhibited cell influx and hypernociception in ZYA in addition to reducing GAG loss and ameliorating synovitis. The A. suum extract reduced i.a. levels of NO, interleukin-1 beta (IL-1 beta), and IL-10 but not tumor necrosis factor alpha (TNF-alpha) in rats subjected to ZYA while reducing i.a. IL-10, but not IL-1 beta or TNIT-alpha, levels in mice. Clinically, mice subjected to CIA treated with the A. suum extract had less severe arthritis. Hypernociception, myeloperoxidase activity, and synovitis severity were significantly reduced. These data show that a helminth extract given p.o. protects from arthritis severity in two classical arthritis models. This A. suum effect is species independent and functions orally and parenterally. The results show clinical and structural benefits when A. suum extract is given either prophylactically or therapeutically.

Nitric oxide-mediated anxiolytic-like and antidepressant-like effects in animal models of anxiety and depression

The effects of microinjection of the nitric oxide (NO) precursor L-arginine (L-Arg), the NO synthase (NOS) inhibitors N-methyl-L-arginine (L-NAME) and 7-nitroindazole (7-NI), and the cyclic guanosine 3`,5`-monophosphate (cGMP) analog 8-Br-cGMP into the dorsal raphe nucleus (DRN) were assessed in rats using the elevated plus maze (EPM) and the forced swim test (FST). L-Arg (100 and 200 nmol) produced an anxiolytic-like effect in the EPM. 8-Br-cGMP (25 and 50 nmol) dose-dependently increased locomotor activity. In the FST, antidepressant-like effects were produced by L-Arg (50 and 100 nmol) and 8-Br-cGMP (12.5 and 25 nmol). Dual effects were observed with NOS inhibitors L-NAME and 7-NI in both the EPM and FST. While low doses of L-NAME (25 nmol) or 7-NI (1 nmol) induced a selective increase in EPM open arm exploration and a decrease in immobility time in the FST, high doses (L-NAME 400 nmol, 7-NI 10 nmol) decreased locomotor activity. These results show that interference with NO-mediated neurotransmission in the DRN induced significant and complex motor and emotional effects. Further studies are needed to elucidate the mechanisms involved in these effects. (C) 2007 Elsevier Inc. All rights reserved.

An anti-inflammatory lectin from Luetzelburgia auriculata seeds inhibits adhesion and rolling of leukocytes and modulates histamine and PGE2 action in acute inflammation models

To study and characterize the in vivo effect of the lectin from Luetzelburgia auriculata seed on acute inflammation models. The lectin was purified from the crude saline extract by affinity chromatography on a guar-gum matrix. Native, heat-treated, and digested lectin was evaluated for anti-inflammatory activity by using peritonitis and paw edema models. The anti-inflammatory activity was characterized by intravital microscopy, nitric oxide production, and myeloperoxidase activity. The lectin exhibited anti-inflammatory activity (2 mg/kg) on both models, reducing local myeloperoxidase activity. Galactose or heat treatment (100A degrees C, 10 min) reduced anti-inflammatory action. Anti-inflammation involves the inhibition of adhesion and rolling of leukocytes along with augmentation of nitric oxide in serum. The lectin inhibited the edematogenic effect of histamine and prostaglandins (PGE2) but did not alter the chemoattractant effect of IL-8. The results indicate that this lectin is a potent anti-inflammatory molecule. Its effects engage diverse modulatory events.