Antioxidants improve antibacterial function in hyperoxia-exposed macrophages

Hyperoxia and pulmonary infections are well known to increase the risk of acute and chronic lung injury in newborn infants, but it is not clear whether hyperoxia directly increases the risk of pneumonia. The purpose of this study was to examine: (1) the effects of hyperoxia and antioxidant enzymes on inflammation and bacterial clearance in mononuclear cells and (2) developmental differences between adult and neonatal mononuclear cells in response to hyperoxia. Mouse macrophages were exposed to either room air or 95% O2 for 24 h and then incubated with Pseudomonas aeruginosa. After 1 h, bacterial adherence, phagocytosis, and macrophage inflammatory protein (MIP)-1alpha production were analyzed. Bacterial adherence increased 5.8-fold (p < 0.0001), phagocytosis decreased 60% (p < 0.05), and MIP-1alpha production increased 49% (p < 0.05) in response to hyperoxia. Overexpression of MnSOD or catalase significantly decreased bacterial adherence by 30.5%, but only MnSOD significantly improved bacterial phagocytosis and attenuated MIP-1alpha production. When monocytes from newborns and adults were exposed to hyperoxia, phagocytosis was impaired in both groups. However, adult monocytes were significantly more impaired than neonatal monocytes. Data indicate that hyperoxia significantly increases bacterial adherence while impairing function of mononuclear cells, with adult cells being more impaired than neonatal cells. MnSOD reduces bacterial adherence and inflammation and improves bacterial phagocytosis in mononuclear cells in response to hyperoxia, which should minimize the development of oxidant-induced lung injury as well as reducing nosocomial infections.     

Effect of adrenalectomy on rat peritoneal macrophage response

Glucocorticoid hormones are important for vital functions and act to modulate inflammatory and immune responses. In contrast to other hormonal systems no endogenous mediators have been identified that can directly counter-regulate their potent anti-inflammatory and immunosuppressive properties. Glucocorticoids are known to interfere with the ability of the macrophage not only to induce and amplify an immune response but also to inhibit macrophage inflammatory effector functions. Although the actual immunocompetence of animals undergoing endocrine gland ectomy has never been directly studied, there is no doubt that adrenal hormones are deeply involved in the development and maintenance of the immunitory functions and this may in turn influence the inflammatory reaction. To study the effect of endogenous glucocorticoids on the functions of rat peritoneal macrophages and induction of humoral immune response we observed some of the rat peritoneal macrophage effector functions, provided that endogenous glucocorticoids are depicted by adrenalectomy. The mean phagocytic index (PI) of control macrophage (Mphi) is increased from 23,825 +/- 427 to 31,895 +/- 83 after adrenalectomy (P < or = 0.001). Intracellular killing capacity in control cell is 82% which is found to be 73% in case of adrenalectomised cell (p < 0.05). The amount of nitric oxide released from control Mphi 20.25 +/- 1 microM following adrenalectomy shows the amount of nitric oxide release was 18.25 microM (p < or = 0.01 ). The percentage of DNA fragmentation in control Mphi was 68.82 +/- 4 which was reduced to 56.76 +/- 1 after adrenalectomy (p < or = 0.01). In sheep red blood cell (SRBC) immunised and adrenalectomised animal, agglutination titre was obtained at lowest antibody concentration (1 : 128) whereas serum from SRBC immunised normal rats showed early agglutination (1: 32). Endogenous glucocorticoid depleted rats show enhanced phagocytic capacity, antibody raising capacity as well as on the other hand adrenal hormone insufficiency reduces the intracellular killing capacity, nitric oxide (NO) release, improper cell maturation and heightens the probability of infection. These observations demonstrate a counter-regulatory system via glucocorticoid that functions to control inflammatory and immune responses.     

Ceramic modifications of porous titanium: Effects on macrophage activation

Porous titanium is one of the most widely used implant materials because of its mechanical properties, however, it is also characterised by low bioactivity. To improve the above parameter we prepared three modifications of the porous (30 wt%) titanium (Ti) surface by covering it with bioactive hydroxyapatite (HA), bioglass (BG) and calcium silicate (CS). Subsequently we tested the impact of the modifications on macrophages directing the inflammatory response that might compromise the implant bioactivity. In the study we investigated the in vitro effects of the materials on murine cell line RAW 264.7 macrophage adherence, morphology and activation (production/release of metalloproteinase MMP-9 and pro- and anti-inflammatory cytokines). CS Ti decreased the macrophage adherence and up-regulated the release of several pro-inflammatory mediators, including TNF-α, IL-6, IL-12. Also HA Ti reduced the cell adherence but other parameters were generally not increased, except of TNF-α. In contrast, BG Ti improved macrophage adherence and either decreased production of multiple mediators (MMP-9, TNF-α, IFN-γ, MCP-1) or did not change it in comparison to the porous titanium. We can conclude that analyzing the effects on the inflammatory response initiated by macrophages in vitro, calcium silicate did not improve the biological properties of the porous titanium. The improved bioactivity of titanium was, however, achieved by the application of the hydroxyapatite and bioglass layers. The present in vitro results suggest that these materials, HA Ti and especially BG Ti, may be suitable for in vivo application and thus justify their further investigation.     

The biomechanical effect of torsion on humeral shaft repair techniques for completed pathological fractures

In the presence of a tumor defect, completed humeral shaft fractures continue to be a major surgical challenge since there is no "gold standard" treatment. This is due, in part, to the fact that only one prior biomechanical study exists on the matter, but which only compared 2 repair methods. The current authors measured the humeral torsional performance of 5 fixation constructs for completed pathological fractures. In 40 artificial humeri, a 2-cm hemi-cylindrical cortical defect with a transverse fracture was created in the lateral cortex. Specimens were divided into 5 different constructs and tested in torsion. Construct A was a broad 10-hole 4.5-mm dynamic compression plate (DCP). Construct B was the same as A except that the screw holes and the tumor defect were filled with bone cement and the screws were inserted into soft cement. Construct C was the same as A except that the canal and tumor defect were filled with bone cement and the screws were inserted into dry cement. Construct D was a locked intramedullary nail inserted in the antegrade direction. Construct E was the same as D except that bone cement filled the defect. For torsional stiffness, construct C (4.45 ± 0.20 Nm/deg) was not different than B or E (p > 0.16), but was higher than A and D (p < 0.001). For failure torque, construct C achieved a higher failure torque (69.65 ± 5.35 Nm) than other groups (p < 0.001). For the failure angle, there were no differences between plating constructs A to C (p ≥ 0.11), except for B versus C (p < 0.05), or between nailing groups D versus E (p = 0.97), however, all plating groups had smaller failure angles than both nailing groups (p < 0.05). For failure energy, construct C (17.97 ± 3.59 J) had a higher value than other groups (p < 0.005), except for A (p = 0.057). Torsional failure always occurred in the bone in the classic "spiral" pattern. Construct C provided the highest torsional stability for a completed pathological humeral shaft fracture.     

Lack of CCR2 results in increased mortality and impaired leukocyte activation and trafficking following infection of the central nervous system with a neurotropic coronavirus

In the present study, we evaluated the role of CCR2 in a model of viral-induced neurologic disease. An orchestrated expression of chemokines, including the CCR2 ligands monocyte chemoattractant protein-1/CCL2 and monocyte chemoattractant protein-3/CCL7, occurs within the CNS following infection with mouse hepatitis virus (MHV). Infection of mice lacking CCR2 (CCR2(-/-)) with MHV resulted in increased mortality and enhanced viral recovery from the brain that correlated with reduced (p < or = 0.04) T cell and macrophage/microglial (determined by F4/80 Ag expression, p < or = 0.004) infiltration into the CNS. Moreover, MHV-infected CCR2(-/-) mice displayed a significant decrease in Th1-associated factors IFN-gamma (p < or = 0.001) and RANTES/CCL5 (p < or = 0.002) within the CNS as compared with CCR2(+/+) mice. Further, peripheral CD4(+) and CD8(+) T cells from immunized CCR2(-/-) mice displayed a marked reduction in IFN-gamma production in response to viral Ag and did not migrate into the CNS of MHV-infected recombination-activating gene (RAG)1(-/-) mice following adoptive transfer. In addition, macrophage/microglial infiltration into the CNS of RAG1(-/-) mice receiving CCR2(-/-) splenocytes was reduced (p < or = 0.05), which correlated with a reduction in the severity of demyelination (p < or = 0.001) as compared with RAG1(-/-) mice receiving splenocytes from CCR2(+/+) mice. Collectively, these results indicate an important role for CCR2 in host defense and disease by regulating leukocyte activation and trafficking.     

The effects on immune response of levamisole treatment following infection of U-937 macrophages with Candida albicans

The aim of this study was to investigate the effects on the immune response of levamisole alone and in conjunction with Candida albicans stimulation in human macrophage cell culture by determining the alterations in the levels of cytokine release. Levamisole treatment was performed before, during and after infecting U-937 human macrophage cells with C. albicans. In cell supernatants, interleukin (IL)-1b, IL-12, IL-18, tumour necrosis factor alpha (TNF-α) levels were measured by ELISA. In vitro levamisole treatment accompanied by C. albicans stimulation significantly increased IL-12, IL-1β and IL-18 production in macrophage cells (p < 0.05). It was observed that when administered before C. albicans infection, levamisole significantly increased IL-12 and IL-1β production in macrophage cells (p < 0.05). Another finding was that when applied to macrophage cells simultaneously with C. albicans infection, or before infection with C. albicans, levamisole suppressed the TNF-β production stimulating effect of C. albicans (p < 0.05). These results indicated that levamisole could be useful in treating patients infected with C. albicans or in protecting individuals under the risk of being infected with this pathogen. There is a need for further experimental and clinical studies on this hypothesis.     

Water jet cutting for bones and bone cement--parameter study of possibilities and limits of a new method]

Water jet techniques have been used in industrial cutting, drilling and cleaning applications for more than 30 years. Plain water is typically used for the cutting of non-metallic materials. The addition of abrasive substances to the stream allows almost any material to be cut. The first medical applications were reported in the early 1980s, when the water jet was used to cut organs. The present study investigates the use of water jet cutting technology for endoprosthesis revision surgery. Bone and PMMA (polymethylmethacrylate) samples were cut at different pressures using an industrial water jet cutting device. Using plain water at 400 bar, PMMA was cut selectively without damaging the bone; above 400 bar, bone was also cut, but the cutting depths in PMMA were significantly greater (p < 0.05). Adding a water-soluble abrasive disaccharide to the water results in a significantly higher removal rate for both materials (p < 0.05), but selectivity is lost, although the differences in cutting depth between the two materials was significant (p < 0.05). With an abrasive, the quality of the cut was better for both materials. The water jet technology--in particular the abrasive technique--can be used to cut biomaterials such as bone and bone cement. The diameter of the jet is a great advantage when working in the confined area at the prosthesis interface. The cutting process is essentially cold, thus eliminating a thermal effect, and the jet reaction forces are relatively low. Accurate manipulation of the hydro jet nozzle is possible both manually and by robot. The results obtained show that it is possible to remove prostheses with this cutting technique, rapidly and with little damage to the surrounding tissue. Problem areas are the development of sterile pumps and the "depth control" of the jet.     

Pharmacological characterisation of anti-inflammatory compounds in acute and chronic mouse models of cigarette smoke-induced inflammation

Background

Candidate compounds being developed to treat chronic obstructive pulmonary disease are typically assessed using either acute or chronic mouse smoking models; however, in both systems compounds have almost always been administered prophylactically. Our aim was to determine whether the prophylactic effects of reference anti-inflammatory compounds in acute mouse smoking models reflected their therapeutic effects in (more clinically relevant) chronic systems.

Methods

To do this, we started by examining the type of inflammatory cell infiltrate which occurred after acute (3 days) or chronic (12 weeks) cigarette smoke exposure (CSE) using female, C57BL/6 mice (n = 7-10). To compare the effects of anti-inflammatory compounds in these models, mice were exposed to either 3 days of CSE concomitant with compound dosing or 14 weeks of CSE with dosing beginning after week 12. Budesonide (1 mg kg^-1; i.n., q.d.), roflumilast (3 mg kg^-1; p.o., q.d.) and fluvastatin (2 mg kg^-1; p.o., b.i.d.) were dosed 1 h before (and 5 h after for fluvastatin) CSE. These dose levels were selected because they have previously been shown to be efficacious in mouse models of lung inflammation. Bronchoalveolar lavage fluid (BALF) leukocyte number was the primary endpoint in both models as this is also a primary endpoint in early clinical studies.

Results

To start, we confirmed that the inflammatory phenotypes were different after acute (3 days) versus chronic (12 weeks) CSE. The inflammation in the acute systems was predominantly neutrophilic, while in the more chronic CSE systems BALF neutrophils (PMNs), macrophage and lymphocyte numbers were all increased (p < 0.05). In the acute model, both roflumilast and fluvastatin reduced BALF PMNs (p < 0.01) after 3 days of CSE, while budesonide had no effect on BALF PMNs. In the chronic model, therapeutically administered fluvastatin reduced the numbers of PMNs and macrophages in the BALF (p ≤ 0.05), while budesonide had no effect on PMN or macrophage numbers, but did reduce BALF lymphocytes (p < 0.01). Roflumilast''s inhibitory effects on inflammatory cell infiltrate were not statistically significant.

Conclusions

These results demonstrate that the acute, prophylactic systems can be used to identify compounds with therapeutic potential, but may not predict a compound''s efficacy in chronic smoke exposure models.     

Surface roughness of denture base and reline materials after disinfection by immersion in chlorhexidine or microwave irradiation

doi: 10.1111/j.1741‐2358.2011.00484.x
Surface roughness of denture base and reline materials after disinfection by immersion in chlorhexidine or microwave irradiation Background: This study evaluated the effect of disinfection by immersion and microwave irradiation on the roughness of one denture base resin (Lucitone‐L) and five relining materials, three hard (Tokuyama Rebase II‐TR, New Truliner‐NT, Ufigel Hard‐UH) and two resilient (Trusoft‐T, Sofreliner‐S). Methods: Fifty specimens were made and divided into groups: CL2 specimens were brushed with 4% chlorhexidine (1 min), immersed in the same solution (10 min) and immersed in water (3 min); MW2 specimens were immersed in water and microwave irradiated (650W; 6 min); CL2 and MW2 specimens were disinfected twice; CL7 and MW7 specimens were submitted to seven cycles using chlorhexidine or microwave irradiation, respectively; W specimens were not disinfected and remained in water (37°C; 7 days). Results: Results were statistically analysed (p = 0.05) and revealed that, at baseline, the highest mean value was observed for T (p < 0.001). Material NT showed increase in roughness after the first (p = 0.003), second (p = 0.001), seventh (p = 0.000) cycles of microwave disinfection and after 7 days of immersion in water (p = 0.033). Conclusions: Resilient liner S presented significant increase in roughness after the second cycle of disinfection with chlorhexidine (p = 0.003). Material T exhibited significantly decreased roughness in group W (p = 0.010), while microwaving produced severe alterations on its surface.     

Effect of different frequencies of creatine supplementation on muscle size and strength in young adults

The purpose was to determine if creatine supplementation, consumed immediately before and immediately after exercise, with different dosing frequency (i.e., 2 or 3 d wk) could enhance the gains in muscle size and strength from resistance training (RT) in young adults. A group of 38 physically active, nonresistance trained university students (21-28 years) was randomly allocated to 1 of 4 groups: CR2 (0.15 g·kg creatine during 2 d wk of RT; 3 sets of 10 repetitions; n = 11, 6 men, 5 women), CR3 (0.10 g·kg creatine during 3 d wk of RT; 2 sets of 10 repetitions; n = 11, 6 men, 5 women;), PLA2 (placebo during 2 d wk of RT; n = 8, 5 men, 3 women), and PLA3 (placebo during 3 d wk of RT; n = 8, 4 men, 4 women) for 6 weeks. Before and after training, measurements were taken for muscle thickness of the elbow and knee flexor and extensor muscle groups (ultrasound), 1-repetition maximumleg press and chest press strength, and kidney function (urinary microalbumin). Repeated-measures analysis of variance showed that strength and muscle thickness increased in all groups with training (p < 0.05). The CR2 (0.6 ± 0.9 cm or 20%; p < 0.05) and CR3 groups (0.4 ± 0.6 cm or 16.4%; p < 0.05) experienced greater change in muscle thickness of the elbow flexors compared to the PLA2 (0.05 ± 0.5 cm or 2.3%) and PLA3 groups (0.13 ± 0.7 cm or 6.3%). Men supplementing with creatine experienced a greater increase in leg press strength (77.3 ± 51.2 kg or 62%) compared to women on creatine (21.3 ± 10 kg or 34%, p < 0.05). We conclude that creatine supplementation during RT has a small beneficial effect on regional muscle thickness in young adults but that giving the creatine over 3 d wk did not differ from giving the same dose over 2 d wk.     

Macrophage CD74 contributes to MIF-induced pulmonary inflammation

Background

MIF is a critical mediator of the host defense, and is involved in both acute and chronic responses in the lung. Neutralization of MIF reduces neutrophil accumulation into the lung in animal models. We hypothesized that MIF, in the alveolar space, promotes neutrophil accumulation via activation of the CD74 receptor on macrophages.

Methods

To determine whether macrophage CD74 surface expression contributes MIF-induced neutrophil accumulation, we instilled recombinant MIF (r-MIF) into the trachea of mice in the presence or absence of anti-CD74 antibody or the MIF specific inhibitor, ISO-1. Using macrophage culture, we examined the downstream pathways of MIF-induced activation that lead to neutrophil accumulation.

Results

Intratracheal instillation of r-MIF increased the number of neutrophils as well as the concentration of macrophage inflammatory protein 2 (MIP-2) and keratinocyte-derived chemokine (KC) in BAL fluids. CD74 was found to be expressed on the surface of alveolar macrophages, and MIF-induced MIP-2 accumulation was dependent on p44/p42 MAPK in macrophages. Anti-CD74 antibody inhibited MIF-induced p44/p42 MAPK phosphorylation and MIP-2 release by macrophages. Furthermore, we show that anti-CD74 antibody inhibits MIF-induced alveolar accumulation of MIP-2 (control IgG vs. CD74 Ab; 477.1 ± 136.7 vs. 242.2 ± 102.2 pg/ml, p < 0.05), KC (1796.2 ± 436.1 vs. 1138.2 ± 310.2 pg/ml, p < 0.05) and neutrophils (total number of neutrophils, 3.33 ± 0.93 × 10⁴ vs. 1.90 ± 0.61 × 10⁴, p < 0.05) in our mouse model.

Conclusion

MIF-induced neutrophil accumulation in the alveolar space results from interaction with CD74 expressed on the surface of alveolar macrophage cells. This interaction induces p44/p42 MAPK activation and chemokine release. The data suggest that MIF and its receptor, CD74, may be useful targets to reduce neutrophilic lung inflammation, and acute lung injury.     

Two short, daily activity bouts vs. one long bout: are health and fitness improvements similar over twelve and twenty-four weeks?

This study sought to determine whether a 12-week intermittent (INT; 2 x 15 min.d(-1)) exercise program yielded similar improvements in cardiovascular health and fitness, compared with a traditional 12-week, 30-minute continuous (CON; 1 x 30 min.d(-1)) exercise program. A second purpose was to determine the effects of switching exercise programs and continuing training for an additional 12 weeks. Twenty women and 17 men, (age 48.8 +/- 9.0 years) were divided randomly into 2 groups: INT (n = 20) and CON (n = 17). Aerobic exercise was performed 4 d.wk(-1) for 12 weeks. Subjects then crossed over to the opposite training program for an additional 12 weeks of training. Subjects exercised incrementally for weeks 1-4 and training was conducted at 70-80% heart rate reserve for weeks 5-24. Both groups showed comparable exercise adherence, completing 96.6 +/- 12.2% (CON) and 96.3% +/- 17.7% (INT) of the prescribed exercise time. The INT walked at a lower percentage of Vo(2)max, maximum heart rate, systolic blood pressure, and diastolic blood pressure (p < 0.05). Maximal oxygen consumption increased by 4.5% in CON and by 8.7% in INT. Following the second 12 weeks, Vo(2)max increased by 3.6 and 7.7% in CON and INT, respectively. Treadmill test time increased by 41 seconds in CON (p < 0.05) and 71 seconds in INT (p < 0.05) after 12 weeks of training. High-density lipoproteins significantly increased in the INT group following the first 12 weeks of training. This study suggests that an INT exercise program, which is incremental in nature, provides comparable, and in some cases greater, health and fitness benefits than those expected following traditional CON exercise training.     

Six months of supervised high-intensity low-volume resistance training improves strength independent of changes in muscle mass in young overweight men

To determine the effects of a 6-month supervised low-volume resistance training (RT) program (1 set, 85-90%, one repetition maximum, 1RM, 3 d x wk(-1)) on muscular strength (1RM) and skeletal muscle mass (SMM) in previously sedentary, overweight men on an ad libitum diet. Nineteen men were randomly assigned to a control (CON, n = 8) or RT (n = 11) group. The exercise protocol consisted of 5 upper- and 4 lower-body exercises using weight machines. CON maintained their sedentary lifestyle. One RM for upper body (chest press [CP] + lat pull-down [LPD]) and lower body (leg press [LP]) and SMM were assessed at baseline, and at 3 and 6 months. Adherence was 96 +/- 2% with an average time to complete each exercise session of 15 +/- 2 minutes. Volume completed per exercise session significantly increased from baseline (2,812 +/- 670 kg) to 6 months (6,411 +/- 2,128 kg). There was a group by time interaction in 1RM for CP, LPD, and LP. Upper-body strength increased significantly (p < 0.001) (31.3 +/- 9.3%) from baseline to 3 months and from 3 to 6 months (17.9 +/- 8.7%). Lower-body strength also increased significantly from baseline to 3 months (17.8 +/- 16.6%) and from 3 to 6 months (32.0 +/- 33.7%). No changes in upper- or lower-body strength occurred in the CON group. There was no group by time interaction for SMM (CON, 34.5 +/- 2.9 kg vs. RT, 34.2 +/- 2.9 kg; p > 0.05) or for energy intake (p > 0.05). In conclusion, a single set resistance training program at 85% of 1RM, 3 d x wk(-1) resulted in continued increases in muscular strength and a very high adherence rate over a 6-month period in sedentary, overweight men independent of significant changes in SMM. This training protocol may increase adherence and produce long-term increases in muscular fitness as part of an adult fitness program.     

Statin treatment increases formation of carbon monoxide and bilirubin in mice: a novel mechanism of in vivo antioxidant protection

Heme oxygenase (HO) has a central role in cellular antioxidant defences and vascular protection, and it may mediate pleiotropic actions of drugs used in cardiovascular therapy. We investigated whether long-term use of statins upregulates HO activity and increases carbon monoxide (CO) and bilirubin levels in vivo. Adult FvB mice were given atorvastatin or rosuvastatin (5 mg/kg) daily by i.p. injections for 1, 2, or 3 weeks. HO activity, tissue CO, bilirubin, and antioxidant levels, total plasma bilirubin, and carboxyhemoglobin (COHb) were measured. Fold changes in heart HO activity significantly increased after 1, 2, and 3 weeks of atorvastatin (1.24 +/- 0.06 (p < or = 0.05); 1.29 +/- 0.26 (p < or = 0.03); 1.33 +/- 0.08 (p < 0.01), respectively) and 2 and 3 weeks of rosuvastatin (1.23 +/- 0.20 (p < or = 0.03); 1.63 +/- 0.42 (p < 0.01), respectively). Heart tissue CO and COHb levels also increased after 3 weeks with atorvastatin (1.30 +/- 0.24 (p < or = 0.05); 1.92 +/- 0.17 (p < or = 0.001), respectively) and rosuvastatin (1.47 +/- 0.13 (p < or = 0.004); 1.63 +/- 0.12 (p < or = 0.001), respectively). Significant increases in heart antioxidant levels were observed after statin treatment and corroborated by heart bilirubin content elevations. Antioxidant level increases were abolished by treatment with an HO inhibitor. These findings suggest that the induction of HO and the production of its products, CO and bilirubin, may be a mechanism by which statins exert antioxidant actions and confer cardioprotection in vivo.     

The effects of natural biofilms on the reattachment of young adult zebra mussels to artificial substrata

This laboratory study examined the effects of natural biofilms on the reattachment of young adult zebra mussels, Dreissena polymorpha, in Petri dishes. Natural biofilms were developed in glass and polystyrene Petri dishes using water samples collected at various times of the year. Biofilms were developed over 1, 3, 8, and 14 d. Controls were clean glass and polystyrene Petri dishes. Zebra mussels collected from the field (< or = 10 mm, ventral length) were placed in the dishes and their reattachment by byssal threads was recorded after 1 d. Zebra mussels reattached to the dish surface or the shells of other mussels in the dish, or remained unattached. The data indicate that reattachment to clean glass was greater than to clean polystyrene (p < or = 0.05, ANOVA), but there were no consistent differences between reattachment to filmed polystyrene and filmed glass dish surfaces. Zebra mussels in control and filmed glass dishes reattached in higher percentages to the dish surface compared to the shells of other mussels (p < or = 0.05, ANOVA). There was no difference in mussel of reattachment between the dish surface and the shells of other mussels in most control polystyrene dishes (p > 0.05, ANOVA), whereas in filmed polystyrene the percentage of reattachment to the dish surface was greater than to the shells of other mussels (p < or = 0.05, ANOVA). These results indicate that substratum wettability and the presence of biofilms on some types of substrata can be factors in the reattachment of young adult zebra mussels.     

Aspects of peridomiciliary ecotopes in rural areas of northeastern Brazil associated to triatomine (Hemiptera, Reduviidae) infestation, vectors of chagas disease

Artificial ecotopes of 121 peridomiciliary environments in four rural localities in the state of Ceará, Brazil, were studied and the type of material of the ecotopes was identified as triatomine infestation. Two thousand two hundred and four Triatoma brasiliensis Neiva, 340 Triatoma pseudomaculata Corrêa and Espínola, 121 Rhodnius nasutus Stall, and 5 Panstrongylus lutzi (Neiva and Pinto) were captured. Out of the 323 ecotopes found (X = 2.0 +/- 1.8 per dwelling) - such as pigpens, henhouses, corrals, perches, dovecotes, piles of roofing tiles, bricks, wood, and straw - 30.3% were infested by triatomines in all different developmental stages, including eggs. A substantial number of triatomines were found in perches, however the largest infestation took place in roofing materials used in the construction of goat/sheep corrals, henhouses, and pigpens, where 98% of them were captured: 1372 triatomines were located in the roofing tile covers, 285 in the straw, 187 in the perches, 77 in the coverings of roofing tiles and straw, and 13 in the straw and wood Among all the different pile of materials, roofing tiles were the most infested (50%) followed by bricks (38.9%) and woods (36.1%). T. brasiliensis colonized mainly brick piles (chi-squared = 16.539; p < 0.05) and roofing tiles (chi-squared = 5,090.58; p < 0.05); T. pseudomaculata preferred wood perches (chi-squared = 472.39; p < 0.05) and woodpiles (chi-squared = 126.0 p < 0.05), and R. nasutus was principally found in roofing straw (chi-squared = 384.43; p < 0.05). These findings suggest that triatomines tend to colonize peridomiciliary ecotopes similar to their original habitats.     

Changes in the essential oil composition in the needles of Scots pine (Pinus sylvestris L.) under anthropogenic stress

Unfavorable anthropogenic factors, such as air pollution, lead to biochemical responses in trees. Changes in the amounts of secondary metabolites may be early indicators of invisible injuries. The aim of this study was to evaluate composition of the essential oils in the needles of Scots pine (Pinus sylvestris L.) growing in the areas affected by pollutant emissions of main factories in Lithuania: a nitrogen fertilizer factory (NFF), a cement factory (CF), and an oil refinery (OR). Totally, 14 pine stands were examined along transects from the factories (July 2005). Volatile components of the needles were extracted and analyzed by GC and GC/MS. Over 70 components of the essential oils were identified in current-year and 1-year-old needles. Along the CF transect for current-year needles, the percentage of diterpenes was decreasing with the increasing pH of the pine bark (r = -0.582; p < 0.05) or with the increasing concentration of SO2 (r = -0.573; p < 0.05); for 1-year-old needles, the percentage of diterpenes was decreasing with the increasing pH of the bark (r = -0.534; p < 0.05). Along the OR transect, in both the current-year and 1-year-old needles, the percentage of diterpenes was decreasing with the increasing SO2 (respectively, r = -0.773; p < 0.01; r = -0.486; p < 0.05); an opposite relation was true for sesquiterpenes (respectively, r = -0.751; p < 0.01; r = 0.785; p < 0.01). The view was different along the NFF transect. For current-year needles, the percentage of monoterpenes was decreasing with the increasing NH3 (r = -0.669; p < 0.01); while the percentage of sesquiterpenes or oxysesquiterpenes was increasing with the increasing NH3 (respectively, r = 0.540; p < 0.05 and r = 0.688; p < 0.01). For each transect, cluster analysis of the percentages of components of essential oils in the needles allowed us to distinguish the most contrasting stands according to the concentration of air pollutants. Current-year needles were more effective as indicators of the effects of pollution than 1-year-old needles in the case of the NFF and the OR transects, and both-aged needles were equally valuable in the case of the CF transect. The changes detected in the proportions of components of the essential oils in the needles of the trees affected by the industrial emissions may play a significant role in modifying the susceptibility of the pine stands to the biotic factors, and also may alter emissions of terpenes from the stands to the atmosphere.     

Two distinctive patterns of monocyte immunoregulatory and effector functions in heavy human infections with Schistosoma mansoni

We evaluated the relationship between immunoregulatory and effector functions of monocytes in subjects with heavy S. mansoni infection (greater than 400 eggs/g of stool). Two main patterns were found. In seven individuals (mean 601 eggs/g), the depletion of adherent cells from peripheral blood mononuclear cells (PBMC) increased blastogenic responses to soluble worm antigenic preparation (SWAP) from a stimulation index (SI) of 3.2 +/- 1.0 to 11.0 +/- 3.0 (p less than 0.01). The presence of indomethacin (1.0 micrograms/ml) in cultures of PBMC from these subjects increased the SWAP response to 7.1 +/- 2.0 (p less than 0.05). In contrast, neither adherent cell depletion nor indomethacin affected blastogenesis induced by nonschistosome antigens or nonspecific mitogens. In this group of infected individuals, monocyte killing of schistosomula and adherence to plastic were increased 122% (p less than 0.01) and 50% (p less than 0.01) over the respective values obtained in uninfected, age-matched controls. A second pattern was found in 10 individuals with a significantly higher intensity of infection (1339 eggs/g of stool (p less than 0.02)). PBMC from these subjects failed to respond significantly to SWAP (SI = 2.0 +/- 0.5), whereas the levels of responses to other antigens and mitogens were maintained at rates comparable to controls. Adherent cell depletion did not significantly affect the blastogenic response (1.8 +/- 0.2), nor did the presence of indomethacin in cultures (2.0 +/- 0.5). Moreover, monocyte-mediated schistosomula killing was depressed in these individuals (50% of controls, p less than 0.05) as was adherence to plastic (77% of controls, p less than 0.05).     

Expression of macrophage functions in hybrids of a myeloma cell line with inflammatory macrophages: Evidence for negative control mechanisms in the expression of macrophage functions

Mouse inflammatory macrophages from C57BL/6N mice were fused with BALB/c mouse-derived myeloma cells (the CANS series). The hybrids in the early period after cell fusion (8 weeks) showed no macrophage functions (chemotaxis, EA and EAC rosette-forming abilities, phagocytosis or lysozyme production). EA rosette-forming ability was observed when these hybrids were treated with trypsin, whereas other macrophage functions were not. After prolonged culture, the hybrids (12 clones of 13 randomly selected) showed all the macrophage functions along with chromosome loss. Myeloma cell functions ( light chain production) were found in the young hybrids soon after cell fusion but were absent in the aged hybrids. These results indicated that reexpression of macrophage properties, except for EA rosette-forming abilities, takes place after the loss of chromosomes or genes repressing the expression of macrophage functions.     

Compositional and structural alterations of chondroitin and dermatan sulfates during the progression of atherosclerosis and aneurysmal dilatation of the human abdominal aorta

Glycosaminoglycans participate in several biological functions in the arterial wall through their specific structures. They undergo specific compositional and structural modifications during the development of vascular diseases. The present study was performed to determine the variations in the concentration and the structural characteristics of galactosaminoglycans--chondroitin sulfate (CS) and dermatan sulfate (DS)--during the progression of atherosclerosis and aneurysmal dilatation of the human abdominal aorta. The concentration of CS was increased 24% (p < or = 0.05) in atherosclerotic type II aortas, but it was significantly decreased (29%, p < or = 0.05) in atherosclerotic type V aortas and aneurysmal aortas (65%, p < or = 0.01). In contrast, the concentration of DS was almost constant in all stages of arterial disease examined. Significant structural alterations were detected in the disaccharide composition of galactosaminoglycans. The ratio of 6-sulfated to 4-sulfated disaccharides was increased in atherosclerotic type II aortas (4.0 instead of 3.1 in normal aortas) due to the marked increase of CS in this tissue. This ratio was significantly decreased in atherosclerotic type V and aneurysmal aortas (2.1 and 1.6, respectively) due to the significant reduction of CS in the respective tissues. In addition, significant decrease of the oversulfated disaccharides, which are mainly located in DS chains, was recorded in atherosclerotic and aneurysmal aortas. Particularly, deltadi-di(2,6)S were decreased 32% (p < or = 0.01) and 86% (p < or = 0.01) in atherosclerotic type II and V aortas and 88% (p < or = 0.01) in aneurysm. Deltadi-di(2,4)S were increased in atherosclerotic type II aortas (21%, p < or = 0.01), but significantly decreased in atherosclerotic type V (33%, p < or = 0.01) and aneurysmal aortas (56%, p < or = 0.01). The amounts of deltadi-di(4,6)S were not markedly affected in the diseased tissues. These results suggest that the concentration of galactosaminoglycans is differentially affected during the progression of atherosclerosis. Furthermore, the development of vascular disease is associated with specific structural modifications, especially with the significant reduction of particular types of oversulfated disaccharides, which may play essential biological roles in the arterial wall.