Endothelins modulate inflammatory reaction in zymosan-induced arthritis: participation of LTB4, TNF-alpha, and CXCL-1

Endothelins (ETs) are involved in inflammatory events, including pain, fever, edema, and cell migration. ET-1 levels are increased in plasma and synovial membrane of rheumatoid arthritis (RA) patients, but the evidence that ETs participate in RA physiopathology is limited. The present study investigated the involvement of ETs in neutrophil accumulation and edema formation in the murine model of zymosan-induced arthritis. Intra-articular (i.a.) administration of selective ETA or ETB receptor antagonists (BQ-123 and BQ-788, respectively; 15 pmol/cavity) prior to i.a. zymosan injection (500 mu g/cavity) markedly reduced knee-joint edema formation and neutrophil influx to the synovial cavity 6 h and 24 h after stimulation. Histological analysis showed that ETA or ETB receptor blockade suppressed zymosan-induced neutrophil accumulation in articular tissue at 6 h. Likewise, dual blockade of ETA/ETB with bosentan (10 mg/kg, i.v.) also reduced edema formation and neutrophil counts 6 h after zymosan stimulation. Pretreatment with BQ-123 or BQ-788 (i.a.; 15 pmol/cavity) also decreased zymosan-induced TNF-alpha production within 6 h, keratinocyte-derived chemokine/CXCL1 production within 24 h, and leukotriene B-4 at both time-points. Consistent with the demonstration that ET receptor antagonists inhibit zymosan-induced inflammation, i.a. injection of ET-1 (1-30 pmol/cavity) or sarafotoxin S6c (0.1-30 pmol/cavity) also triggered edema formation and neutrophil accumulation within 6 h. Moreover, knee-joint synovial tissue expressed ETA and ETB receptors. These findings suggest that endogenous ETs contribute to knee-joint inflammation, acting through ETA and ETB receptors and modulating edema formation, neutrophil recruitment, and production of inflammatory mediators.

Role of olfaction and vision cues in feeding behavior and alarm reaction in the catfish pintado, Pseudoplatystoma corruscans

Experiments were performed to investigate senses that are essential for mediating fright reaction and food behavior in Pseudoplatystoma corruscans, pintado. The dilemma ""to feed or to flee"" was also analyzed in fishes with intact and sectioned olfactory tracts, stimulated by alarm substance extracts and food. Fishes were arranged into five groups: fish with intact lateral olfactory tracts (LOT), fish with intact medial olfactory tract (MOT), fish with tracts totally sectioned (TOTAL, both LOT and MOT), sham operated, and nonoperated fish. The five groups were submitted to either alarm substance extract and food stimulus or to distilled water (control) and food stimulus. Fish reacted to food independently of which tract (LOT, MOT or TOTAL) was sectioned; vision seems necessary and elemental to detect and deflagrate food response. Latency of the responses to each reaction was different between groups. None of the fish with sectioned tracts reacted to alarm substance extract, while sham- and nonoperated fish showed the typical alarm behavior response, leading to the conclusion that olfaction is essential for mediating alarm response. These results indicate that others sense systems (e.g., vision) are sufficient to trigger and elicit feeding behavior and that olfaction is not necessary to fully maintain food detection to qualitative and quantitative extent. However, olfactory tract integrity seems to be required for mediation of alarm reaction in P. corruscans.

Advantages and Pitfalls of the Polymerase Chain Reaction in the Diagnosis of Esophageal Ulcers in AIDS Patients

HIV-1-infected patients frequently have opportunistic esophageal infections which, when associated with severe immunodeficiency, can be attributed to unusual pathogens. The clinical presentation of several esophageal diseases is similar and the best method for a specific diagnosis of these patients has not been well defined. To evaluate the role of the polymerase chain reaction (PCR) in the etiologic definition of esophageal ulcers in HIV-1-infected patients, 96 esophageal biopsies from 79 HIV-1-infected patients were processed by PCR using specific primers for cytomegalovirus (CMV), herpes virus (HSV), human papilloma virus (HPV), HIV-1, Mycobacterium tuberculosis, Mycobacterium avium, Mycobacterium intracellulare, Treponema pallidum, and Haemophilus ducreyi. The PCR results were compared to the histopathologic results. Seventy-nine patients were studied (mean age: 34 years; 62% men; median CD4 + T cell = 103.59 cells/mu l (range 1-795.2 cells/mu l). The most common endoscopic findings were as follows: esophageal candidiasis (37.1%), esophageal ulcers (24.7%), esophagitis (11.2%), and lugol-negative areas (10.1%). The histopathologic findings in the esophageal ulcers (22 biopsies) were non-specific inflammation (31.8%), HSV (36.4%), Candida (13.6%), CMV (13.6%), or HPV disease (4.5%). In the esophageal ulcer biopsies, the PCR results were negative in 27.6% of cases, and positive for HIV (65.5%), CMV (31%), HPV (20.7%), HSV (10.3%), and H. ducreyi (6.9%). The histopathologic examination did not identify a pathogen or identified only Candida in 15 biopsies of esophageal ulcers. PCR was positive in ten (66.7%) and negative in five (33.3%) of these biopsies (idiopathic ulcers). PCR detected: HIV (53.3%), CMV (20%), HPV (13.3%), and H. ducreyi (6,7%). PCR detected more etiologic agents in esophageal ulcers than histopathology and was able to detect unusual pathogens. On the other hand, sometimes more than one pathogen was detected in the esophageal ulcers, making it difficult to reach an accurate diagnosis. This finding indicates the need for more studies to evaluate the benefit of this method in the routine evaluation of esophageal ulcer biopsies in HIV-1-infected patients.

Detection of Leptospira spp. in semen and vaginal fluids of goats and sheep by polymerase chain reaction

Thirteen goat herds and seven sheep flocks in the state of Rio de Janeiro, Brazil were screened for leptospirosis. From the three herds and three flocks with greatest seroreactivity, 19 goats (16 females and three bucks) and 40 sheep (26 ewes and 14 rams) that were seropositive (specific anti-Leptospira titres >= 400, based on a microscopic agglutination test), were selected for more detailed studies. From those animals, samples of vaginal fluids or semen were collected for bacteriological and molecular assays. For both species of animals, the most prevalent reactions were to serovars Hardjo, Shermani, and Grippotyphosa. Although leptospires were detected by darkfield microscopy in three vaginal fluid samples (from two goats and one ewe), pure isolates were not obtained by bacteriological culture of vaginal fluids or semen. However, seven vaginal fluid samples (from four goats and three ewes) and six semen samples (all from rams) were positive on polymerase chain reaction (PCR). Based on these findings, in addition to analogous findings in cattle, we inferred that there is potential for venereal transmission of leptospirosis in small ruminants. (c) 2008 Elsevier Inc. All rights reserved.

Phosphorus kinetics in calves experimentally submitted to a trickle infection with Cooperia punctata

Ten male Holstein calves (74.3 +/- 3.2 kg LW) were used for a trial with trickle infection with Cooperia punctata to evaluate phosphorus (P) kinetics. Five calves were inoculated with 10,000 L(3) stage larvae per week during 35 days, while the other group of five calves was kept as a control. On the 29th day each calf was intravenously injected with 29.6 MBq of a (32)p solution. Blood samples were taken at 24 h periods for 7 days, after which all calves were slaughtered and worms burdens. Faeces, urine and tissue samples were taken for analysis using isotopic dilution and modeling techniques. The number of eggs per gram of faeces (EPG)was 1920 +/- 168 on 28th day and the total number of worms burdens was 11,131 +/- 1500. Infected calves showed lower feed intake and live weight gain, as well as lower P intake, absorption and retention than control calves. The P flows between body compartments were lower for blood to gastrointestinal tract (TGI), TGI to blood, blood to soft tissues, bone balance and soft tissue balance in infected calves when compared to the control. The trickle infection of C punctata affected P metabolism due to the decrease in P retained and live weight due to fall in feed intake. (C) 2009 Elsevier B.V. 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

Visitors' reaction to Pinnawala Elephant Orphanage in Sri Lanka

Pinnawala Elephant Orphanage (PEO) is a unique captive elephant-based recreation facility in Sri Lanka. Over 35,000 visitors (both local and foreign) visit the PEO per month on average for a variety of reasons. However, little or no attempt has been made to examine their reaction to its activities. This paper reports preliminary findings from two visitor surveys (one local and one foreign) conducted at the PEO to examine the characteristics of visitors, the satisfaction they gained from the visit, their attitudes towards conservation of the elephant, their reactions to the current facilities available at the orphanage, and their opinions and maximum willingness to pay (WTP) to enter the PEO. It is found that, although some variations occurred between the samples, the majority of all respondents showed a similar reaction to the activities and facilities at the Orphanage. However, some differences are evident between these two samples in relation to satisfaction received, responses to the WTP elicitation and attitudes towards the information and interpretive facilities. Overall, the majority of the respondents indicated that their support for the conservation of the Asian elephant had increased considerably with their visit to the Orphanage. This indicates that considerable unrecorded and as yet unutilised support could be generated both financially and otherwise to conserve this endangered species through wildlife based recreation facilities such as PEO in Sri Lanka.

Polymerization stress, shrinkage and elastic modulus of current low-shrinkage restorative composites

Objective. To compare currently available low-shrinkage composites with others regarding polymerization stress, volumetric shrinkage (total and post-gel), shrinkage rate and elastic modulus. Methods. Seven BisGMA-based composites (Durafill/DU, Filtek Z250/FZ, Heliomolar/HM, Aelite LS Posterior/AP, Point 4/P4, Filtek Supreme/SU, ELS/EL), a silorane-based (Filtek LS, LS), a urethane-based (Venus Diamond, VD) and one based on a dimethacrylate-derivative of dimer acid (N`Durance, ND) were tested. Polymerization stress was determined in 1-mm high specimens inserted between two PMMA rods attached to a universal testing machine. Total volumetric shrinkage was measured using a mercury dilatometer. Maximum shrinkage rate was used as a parameter of the reaction speed. Post-gel shrinkage was measured using strain-gages. Elastic modulus was obtained by three-point bending. Data were submitted to one-way ANOVA/Tukey test (p = 0.05), except for elastic modulus (Kruskal-Wallis). Results. Composites ranked differently for total and post-gel shrinkage. Among the materials considered as ""low-shrinkage"" by the respective manufacturers, LS, EL and VD presented low post-gel shrinkage, while AP and ND presented relatively high values. Polymerization stress showed a strong correlation with post-gel shrinkage except for LS, which presented high stress. Elastic modulus and shrinkage rate showed weak relationships with polymerization stress. Significance. Not all low-shrinkage composites demonstrated reduced polymerization shrinkage. Also, in order to effectively reduce polymerization stress, a low post-gel shrinkage must be associated to a relatively low elastic modulus. (C) 2010 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

The Potential Role of Suppressors of Cytokine Signaling in the Attenuation of Inflammatory Reaction and Alveolar Bone Loss Associated with Apical Periodontitis

Inflammatory cytokines contribute to periapical tissue destruction. Their activity is potentially regulated by suppressors of cytokine signaling (SOCS), which down-regulate signal transduction as part of an inhibitory feedback loop. We investigated the expression of the cytokines tumor necrosis factor alpha (TNF-alpha); interleukin (IL)-10 and RANKL; and SOCS-1, -2, and -3 by real-time polymerase chain reaction in 57 periapical granulomas and 38 healthy periapical tissues. Periapical granulomas exhibited significantly higher SOCS-1, -2, and -3, TNF-alpha, IL-10, and RANKL messenger RNA levels when compared with healthy controls. Significant positive correlations were found between SOCS1 and IL-10 and between SOCS3 and IL-10. Significant inverse correlations were observed between SOCS1 and TNF-alpha, SOCS1 and RANKL, and SOCS3 and TNF-alpha. Increased SOCS-1, -2, and -3 messenger RNA levels in periapical granulomas may be related to the downregulation of inflammatory cytokines in these lesions; therefore, SOCS molecules may play a role in the dynamics of periapical granulomas development. (J Endod 2008;34:1480-1484)

Kinetics of fluoride removal from plasma and bone of rats after chronic intake of fluoride

This study evaluated the kinetics of fluoride in plasma, femur surface and the whole femur of rats, after chronic exposure to different water fluoride levels was interrupted. Four groups of Wistar rats received drinking water containing 0, 5, 15 or 50 mu g F/ml for 60 days (n = 50/group). The animals were euthanized immediately after exposure to fluoride or after 7, 30, 90 or 180 days (n = 10/subgroup). Plasma and femurs were collected. Fluoride on the femur surface, whole femur and plasma was analyzed with an electrode. Data were analyzed using ANOVA and Tukey`s test (p < 0.05). The increase in plasma fluoride levels was significant only for the 50 mu g F/ml group at 0 and 7 days. Regarding bone surface and whole bone, for most groups, significant increases in fluoride concentrations were observed with the increase in water fluoride concentrations at each time of euthanasia. For fluoride doses up to 15 mu g F/ml, femur surface fluoride levels were reestablished 180 days after the exposure was discontinued, which Was not valid for whole femur or for higher fluoride doses. We found a different kinetics of fluoride in plasma,femur surface and the whole femur of rats after chronic exposure to fluoride is interrupted. Copyright 2008 Prous Science, S.A.U. or its licensors. All rights reserved.

Diffusion modeling of percutaneous absorption kinetics: 2. Finite vehicle volume and solvent deposited solids

The diffusion model for percutaneous absorption is developed for the specific case of delivery to the skin being limited by the application of a finite amount of solute. Two cases are considered; in the first, there is an application of a finite donor (vehicle) volume, and in the second, there are solvent-deposited solids and a thin vehicle with a high partition coefficient. In both cases, the potential effect of an interfacial resistance at the stratum corneum surface is also considered. As in the previous paper, which was concerned with the application of a constant donor concentration, clearance limitations due to the viable eqidermis, the in vitro sampling rate, or perfusion rate in vivo are included. Numerical inversion of the Laplace domain solutions was used for simulations of solute flux and cumulative amount absorbed and to model specific examples of percutaneous absorption of solvent-deposited solids. It was concluded that numerical inversions of the Laplace domain solutions for a diffusion model of the percutaneous absorption, using standard scientific software (such as SCIENTIST, MicroMath Scientific software) on modern personal computers, is a practical alternative to computation of infinite series solutions. Limits of the Laplace domain solutions were used to define the moments of the flux-time profiles for finite donor volumes and the slope of the terminal log flux-time profile. The mean transit time could be related to the diffusion time through stratum corneum, viable epidermal, and donor diffusion layer resistances and clearance from the receptor phase. Approximate expressions for the time to reach maximum flux (peak time) and maximum flux were also derived. The model was then validated using reported amount-time and flux-time profiles for finite doses applied to the skin. It was concluded that for very small donor phase volume or for very large stratum corneum-vehicle partitioning coefficients (e.g., for solvent deposited solids), the flux and amount of solute absorbed are affected by receptor conditions to a lesser extent than is obvious for a constant donor constant donor concentrations. (C) 2001 Wiley-Liss, Inc. and the American Pharmaceutical Association J Pharm Sci 90:504-520, 2001.

Epstein-Barr virus encephalitis in a renal allograft recipient diagnosed by polymerase chain reaction on cerebrospinal fluid and successfully treated with ganciclovir

Epstein–Barr virus (EBV) encephalitis has been reported rarely in the context of solid-organ and bone-marrow transplantation [1]. We report a case of a renal transplant recipient who developed EBV encephalitis following OKT3 therapy for acute allograft rejection. The diagnosis was expedited by the detection of EBV DNA in the cerebrospinal fluid (CSF) by nested polymerase chain reaction (PCR). Moreover, clinical recovery and clearance of CSF EBV DNA appeared to follow the institution of parenteral ganciclovir treatment.

Interpretation of the reversible inhibition of adenosine deaminase by small cosolutes in terms of molecular crowding

Published results on the inhibitory effects of small cosolutes on adenosine deamination by adenosine deaminase [Kurz. L. C.. Weitkamp, E., and Frieden, C. (1987) Biochemistry 26, 3027-3032; Dzingeleski, G., and Wolfenden, R. (1993) Biochemistry 32, 9143 -9147] have been reexamined. Results for sucrose, dioxane, methanol, and ethanol are shown to be qualitatively consistent with thermodynamic interpretation in terms of molecular crowding effects arising from the occurrence of a minor increase in enzyme volume and/or asymmetry during the kinetic reaction-a conformational transition that could be either preexisting or ligand induced. Direct evidence for the existence of the putative isomeric transition is provided by active enzyme gel chromatography on Sephadex G-100, which demonstrates a negative dependence of enzyme elution volume upon substrate concentration and is therefore consistent with substrate-mediated conformational changes that favor a larger (or more asymmetric) isomeric state of the enzyme. There are thus experimental grounds for adopting the present description of the inhibitory effects of unrelated cosolutes on the kinetics of adenosine deamination by adenosine deaminase in terms of thermodynamic nonideality.

Quantitative analysis of the time courses of enzyme-catalyzed reactions

The catalytic properties of enzymes are usually evaluated by measuring and analyzing reaction rates. However, analyzing the complete time course can be advantageous because it contains additional information about the properties of the enzyme. Moreover, for systems that are not at steady state, the analysis of time courses is the preferred method. One of the major barriers to the wide application of time courses is that it may be computationally more difficult to extract information from these experiments. Here the basic approach to analyzing time courses is described, together with some examples of the essential computer code to implement these analyses. A general method that can be applied to both steady state and non-steady-state systems is recommended. (C) 2001 academic Press.