Diet as a Risk Factor for Cognitive Decline in African Americans and Caucasians with a Parental History of Alzheimer's Disease: A Cross-Sectional Pilot Study Dietary Patterns

BACKGROUND

African Americans (AA) are more likely to develop Alzheimer's disease (AD) than Caucasians (CC). Dietary modification may have the potential to reduce the risk of developing AD.

OBJECTIVE

The objective of this study is to investigate the relationship between Southern and Prudent diet patterns and cognitive performance in individuals at risk for developing AD.

DESIGN

Cross-sectional observational study.

PARTICIPANTS

Sixty-six cognitively normal AA and CC individuals aged 46-77 years with a parental history of AD were enrolled.

MEASUREMENTS

Participants completed a Food Frequency questionnaire, cognitive function testing, which consisted of 8 neuropsychological tests, and cardiovascular risk factor assessments, including evaluation of microvascular and macrovascular function and ambulatory blood pressure monitoring.

RESULTS

Results revealed a relationship between the Southern diet and worse cognitive performance among AAs. AAs who consumed pies, mashed potatoes, tea, and sugar drinks showed worse cognitive performance (p<0.05) compared with CCs. In addition, gravy (p=0.06) and cooking oil/fat (p=0.06) showed negative trends with cognitive performance in AAs. In both CC and AA adults, greater adherence to a Prudent dietary pattern was associated with better cognitive outcomes. Cardiovascular results show that participants are overall healthy. AAs and CCs did not differ on any vascular measure including BP, arterial stiffness and endothelial function.

CONCLUSION

Research shows that dietary factors can associate with cognitive outcomes. This preliminary cross-sectional study suggests that foods characteristic of the Southern and Prudent diets may have differential effects on cognitive function in middle-aged individuals at high risk for AD. Results suggest that diet could be a non-pharmaceutical tool to reduce cognitive decline in racially diverse populations. It is possible that the increased prevalence of AD in AA could be partially reduced via diet modification.

Body-weight goals, trends, and weight-loss techniques among patients with peripheral arterial disease

BACKGROUND:

Obesity contributes to negative outcomes in peripheral arterial disease (PAD). Little is known about the body-weight goals and trends among patients with PAD.

AIM:

The aim of this study was to explore self-reported body-weight trends and methods used to achieve weight loss in patients with PAD.

METHODS:

Data from the 1999-2004 National Health and Nutrition Examination Survey (NHANES) was utilized to compare individuals with PAD who were overweight and obese ( n = 240), to matched individuals without PAD ( n = 480). Self-reported body weight at age 25 years, 10 years prior and 1 year prior to the current assessment, and age and weight of heaviest body weight were compared. Self-reported weight-loss techniques during the past year were compared between groups.

RESULTS:

Individuals with PAD and controls reported similar weights 10 years prior (79.2 kg vs 78.5 kg; p = 0.60) and weight gain over the last 10 years of 5.7 kg. There was no significant difference in reported body weight at age 25 years, 10 years prior, 1 year prior, or heaviest weight. Compared with the control group, fewer participants with PAD reported attempted weight loss in the last year (27.50% vs 36.04%; p = 0.02) and were half as likely to report utilizing exercise as a weight-loss method (12.5% vs 21.7%; p = 0.003).

CONCLUSIONS:

These data indicate that those with PAD are less inclined to attempt weight loss, especially through means of increased physical activity. Future research is needed regarding the effectiveness of intentional weight-loss programs in this population.

Reduced LPL and subcutaneous lipid storage capacity are associated with metabolic syndrome in postmenopausal women with obesity

OBJECTIVES

This study examines the hypothesis that lower adipose tissue lipoprotein lipase (LPL) activity and a limited capacity for subcutaneous adipocyte expansion will be associated with metabolic syndrome (MSyn) in postmenopausal women who are overweight and obese.

METHODS

Women (N = 150; age 60 ± 1 year; BMI: 31.5 ± 0.3 kg m^-2; mean ± standard errors of the means [SEM]) with and without MSyn had dual-energy X-ray absorptiometry scans for total body fat, CT scans for visceral and subcutaneous abdominal adipose tissue areas, lipid and glucose metabolic profiles, and abdominal and gluteal fat aspirations for subcutaneous fat cell weight (FCW; N = 150) and LPL activity (N = 100).

RESULTS

Women with MSyn had similar total body fat, but 15% larger abdominal and 11% larger gluteal FCWs and more visceral fat (179 ± 7 vs. 134 ± 6 cm²) than women without MSyn (P's < 0.05). Abdominal LPL activity was 13% (P = 0.18) lower in women with than without MSyn and correlated with abdominal FCW (r = 0.49, P < 0.01) only in those without MSyn. Visceral fat and abdominal and gluteal FCWs correlated with MSyn components, and subcutaneous adipose tissue correlated with abdominal FCW (r = 0.43, P < 0.01) and LPL activity (r = 0.18, P < 0.05), independent of total body fat.

CONCLUSIONS

These results show that women with MSyn have lower LPL activity, limited capacity for subcutaneous adipocyte lipid storage and greater ectopic fat accumulation in viscera than women without MSyn of comparable obesity. This suggests that the development of novel therapies that would enhance adipocyte expandability might prevent the accumulation of ectopic fat and reduce the risk for MSyn in postmenopausal women with obesity.

Dietary prescription adherence and non-structured physical activity following weight loss with and without aerobic exercise

OBJECTIVES

To compare the effects of weight loss with and without exercise on 1) dietary prescription adherence and 2) non-structured activity in postmenopausal women.

DESIGN

Longitudinal study.

SETTING

Clinical research setting with facility based exercise and nutrition education.

PARTICIPANTS

Overweight and obese women, 45-76 years old.

INTERVENTION

6 months of weight loss alone (WL; N=38) or with aerobic exercise (AEX+WL; N=41).

MEASUREMENTS

Cardiorespiratory fitness (VO2max), resting metabolic rate (RMR), seven day food intake, and physical activity (by Actical accelerometers worn in a subset subgroup: WL: N=10; AEX+WL: N=15) were assessed before and after the interventions.

RESULTS

Both interventions resulted in similar weight loss (~9%) and no significant changes in RMR, while only the AEX+WL group improved VO2max (~10%). At baseline, the AEX+WL group consumed slightly more protein than the WL group (P<0.01). Macronutrient intake did not change following AEX+WL, but the WL group decreased their fat intake and increased their carbohydrates and protein intakes (Ps<0.05), which resulted in similar macronutrient intakes between groups post-intervention. Weekday total activity counts decreased 22% (P<0.05) following WL. This change tended (P=0.07) to be different than the lack of change in non-structured activity observed following AEX+WL.

CONCLUSION

Although similar dietary adherence was observed, these data suggest that postmenopausal women undergoing weight loss may benefit from the addition of exercise to prevent the decline in non-structured activity observed following weight loss alone.

[Mitochondrial and microcirculatory distress syndrome in the critical patient. Therapeutic implications]

Mitochondrial and microcirculatory distress syndrome (MMDS) can occur during systemic inflammatory response syndrome (SIRS), and is characterized by cytopathic tissue hypoxia uncorrected by oxygen transport optimization, and associated with an acquired defect in the use of oxygen and energy production in mitochondria, leading to multiple organ dysfunction (MOD). We examine the pathogenesis of MMDS, new diagnostic methods, and recent therapeutic approaches adapted to each of the three phases in the evolution of the syndrome. In the initial phase, the aim is prevention and early reversal of mitochondrial dysfunction. Once the latter is established, the aim is to restore flow of the electron chain, mitochondrial respiration, and to avoid cellular energy collapse. Finally, in the third (resolution) stage, treatment should focus on stimulating mitochondrial biogenesis and the repair or replacement of damaged mitochondria.

IMPACT OF WEIGHT LOSS AND AEROBIC EXERCISE ON NUTRITION AND BONE MINERAL DENSITY IN AFRICAN AMERICAN AND CAUCASIAN POSTMENOPAUSAL WOMEN

BACKGROUND

Weight loss is often recommended for obese women to reduce fat mass and the risk of developing chronic diseases, but may result in a reduction of bone mineral density (BMD). African Americans have greater BMD than Caucasians, but differences in the decrease in BMD between these races following weight reduction with and without exercise are unknown.

OBJECTIVES

The purpose of this study was to investigate the hypothesis that Caucasian women would lose greater amounts of BMD than African American women after undergoing weight loss, but that the addition of aerobic exercise would attenuate the loss in both races.

DESIGN

Longitudinal.

PARTICIPANTS

African American (n=34) and Caucasian (n=63), overweight and obese postmenopausal (age 45-80 years).

INTERVENTION

Six months of weight loss (250-350 kcal/days deficit) alone (WL) or in combination with aerobic exercise consisting of 3 days/week treadmill training at >85% of heart rate reserve for 45 min (AEX+WL).

MEASUREMENTS

Femoral neck, total femur, and lumbar BMD, VO2max, urinary calcium, and dietary intake.

RESULTS

African American women had a greater body weight, BMI, and BMD all sites and lower dietary protein and calcium intakes than Caucasian women (all P<0.05). Weight decreased 7.5% in both groups and VO2max increased only after AEX+WL (intervention effect, P<0.001). Both races lost ~1% of their femoral neck and total femur BMD following the interventions (P's<0.01). There were no race by intervention interactions. There was a trend for the women undergoing WL to lose greater femoral neck BMD than those in AEX+WL (P=0.07). There were no associations between changes in BMD and changes in VO2max, urinary calcium, or dietary intake.

CONCLUSIONS

Our data indicate that despite beginning the interventions with greater BMD than Caucasian postmenopausal women, African Americans were not spared from losses of femoral neck and total femur BMD following six months of weight loss, but that addition of aerobic exercise to weight loss tends to attenuate the decreases in femoral neck BMD in both races.

Microhardness and SEM after CO(2) laser irradiation or fluoride treatment in human and bovine enamel

BACKGROUND

It remains uncertain as to whether or not CO(2) laser is able to hinder demineralization of enamel. The possibility to use bovine instead of human teeth on anticariogenic studies with laser has not yet been determined.

PURPOSE

To compare the ability of CO(2) laser and fluoride to inhibit caries-like lesions in human enamel and to test whether a similar pattern of response would hold for bovine enamel.

STUDY DESIGN

Ninety-six enamel slabs (2 × 2 × 4 mm) (48 from bovine and 48 from human teeth) were randomly distributed according to surface treatment (n = 12): CO(2) laser, 5% sodium fluoride varnish (FV), 1.23% acidulated phosphate fluoride (APF) gel, or no treatment (control). Specimens were subjected to a 14-day in vitro cariogenic challenge. Microhardness (SMH) was measured at 30 μm from the surface. For ultrastructural analysis, additional 20 slabs of each substrate (n = 5) received the same treatment described earlier and were analyzed by SEM.

RESULTS

ANOVA and Tukey test ascertained that CO(2) laser promoted the least mineral loss (SMH = 252(a)). Treatment with FV resulted in the second highest values (207(b)), which was followed by APF (172(c)). Untreated specimens performed the worst (154(d)). SEM showed no qualitative difference between human and bovine teeth. APF and control groups exhibited surfaces covered by the smear layer. A granulate precipitate were verified on FV group and fusion of enamel crystals were observed on lased-specimens.

CONCLUSIONS

CO(2) laser may control caries progression more efficiently than fluoride sources and bovine teeth may be a suitable substitute for human teeth in studies of this nature.

Low relative skeletal muscle mass indicative of sarcopenia is associated with elevations in serum uric acid levels: findings from NHANES III

BACKGROUND

Sarcopenia may be related to increases in reactive oxygen species formation and inflammation, both of which are associated with elevations in serum uric acid.

OBJECTIVE

To test the hypothesis that a reduced skeletal muscle mass index, indicative of sarcopenia, is related to elevations in uric acid.

DESIGN

Cross-sectional analysis of nationally representative data.

SETTING

Third National Health and Nutrition Examination Survey, 1988-1994.

PATIENTS

7544 men and women 40 years of age and older who had uric acid, skeletal muscle mass, and select covariate information.

MEASUREMENTS

Skeletal muscle mass assessment was based on a previously published equation including height, BIA-resistance, gender, and age. Absolute skeletal muscle mass was calculated for all study population individuals and compared against the sex-specific mean for younger adults. Serum uric acid data were gathered from the NHANES laboratory file.

RESULTS

A logistic regression analysis revealed that elevations in serum uric acid are significantly related to sarcopenia status. For every unit (mg/dL) increase in uric acid, the odds ratio of manifesting a skeletal muscle mass index at least one standard deviation below the reference mean was 1.12. Participants in the highest grouping (> 8 mg/dL) of serum uric acid concentration had 2.0 times the odds of manifesting sarcopenia compared to the lowest grouping (< 6 mg/dL) (p < 0.01) after adjusting for the additional covariates.

LIMITATIONS

This study design was limited in its cross-sectional nature. Potential selection, measurement, and recall bias may have occurred, and methodology used to classify sarcopenia status based on skeletal muscle mass index is not validated.

CONCLUSION

This observation provides support for the theory that elevations in uric acid may lead to sarcopenia, although the proposed mechanism needs further experimental support.

Protective effect of the dental pellicle against erosive challenges in situ

The acquired dental pellicle helps prevent erosion, but the protection level is unknown. This in situ study tested whether a two-hour pellicle protects against different erosive challenges by orange juice. Subjects wore palatal appliances loaded with either enamel or dentin specimens. Pellicle was allowed to form, or not (control), on the surfaces of the specimens intra-orally for 2 hrs before the erosive challenges of 0 (control), 10, 20, and 30 minutes' duration. Specimens were randomly removed from the appliances after each challenge. Percentage of surface microhardness change (%SMC) was determined for the enamel specimens, and that of mineral loss and lesion depth for the dentin specimens. Enamel specimens with the pellicle showed a significantly lower %SMC, only after the 10-minute challenge. No protection was found for dentin. It was concluded that the acquired pellicle reduced dental erosion, but that this effect was limited to the less severe erosive challenge on enamel surfaces.

Influence of fluoride-releasing restorative material on root dentine secondary caries in situ

The usefulness of fluoride-releasing restorations in secondary caries prevention may be questioned because of the presence of other common sources of fluoride and because of ageing of the restorations. This study tested the hypothesis that glass-ionomer cement restorations, either aged or unaged, do not prevent secondary root caries, when fluoride dentifrice is frequently used. Sixteen volunteers wore palatal appliances in two phases of 14 days, according to a 2 x 2 crossover design. In each phase the appliance was loaded with bovine root dentine slabs restored with either glass-ionomer or resin composite, either aged or unaged. Specimens were exposed to cariogenic challenge 4 times/day and to fluoridated dentifrice 3 times/day. The fluoride content in the biofilm (FB) formed on slabs and the mineral loss (DeltaZ) around the restorations were analysed. No differences were found between restorative materials regarding the FB and the DeltaZ, for either aged (p = 0.792 and p = 0.645, respectively) or unaged (p = 1.00 and p = 0.278, respectively) groups. Under the cariogenic and fluoride dentifrice exposure conditions of this study, the glass-ionomer restoration, either aged or unaged, did not provide additional protection against secondary root caries.

Influence of the Organic Matrix on Root Dentine Erosion by Citric Acid

This investigation was conducted in an attempt to clarify the role of the organic matrix in bovine dentine demineralisation by 1% citric acid. Dentine slabs (n = 15) were treated for 2 min with 10% sodium hypochlorite (NaOCl, a strong protein solvent), 2% glutaraldehyde (GDA, a protein fixative) or deionised water (DIW, as negative control) prior to each of 5 demineralisation periods of 30 min. The mineral loss (DeltaZ), lesion depth (LD) and surface loss (SL) were determined after each period of demineralisation, by transverse microradiography. The NaOCl-treated group showed higher DeltaZ and LD than the GDA- and DIW-treated groups. No differences between GDA and DIW groups were found. The DeltaZ and LD profiles were explained by quadratic fits (r(2) >0.80; p = 0.001) in all groups. SL was detected only in the NaOCl-treated group. The data suggested that the maintenance of the organic matrix in the lesion might be important to reduce the erosion progression rate.

An in situ Investigation into the Abrasion of Eroded Dental Hard Tissues by a Whitening Dentifrice

This crossover study aimed to investigate abrasion of previously eroded hard dental tissues by a whitening dentifrice compared to a regular dentifrice. After a 3-day lead-in period, 14 volunteers were randomly assigned to use one of the toothpastes while wearing a removable appliance, containing 3 enamel and 3 root dentine slabs on each side. On the first day salivary pellicle was allowed to form. Twice daily for the following 3 days, one side of each appliance was immersed in an acidic carbonated drink ex vivo while the other side remained unexposed. Specimens were then brushed with the allocated dentifrice. After a 3-day washout period, new sets of enamel and dentine slabs were mounted in the appliances and the participants commenced period 2 using the alternative toothpaste. Acid-treated specimens always showed more wear than untreated specimens. The whitening dentifrice did not significantly increase the wear of softened enamel compared with the regular dentifrice. Brushing with the whitening toothpaste led to significantly greater wear of sound enamel and of both eroded and sound dentine than the regular dentifrice. The results suggest that whitening dentifrices may not increase the wear of acid-softened enamel but may have a more deleterious effect on dentine than regular toothpastes.

Effect of non-vital tooth bleaching on microleakage of coronal access restorations

This study evaluated the effect of non-vital tooth bleaching on microleakage of composite resin/bovine tooth interface at different post-bleaching times. A total of 320 teeth were cleaned. A pulp chamber access cavity was made at the lingual surface of each tooth. The teeth were randomly divided into four groups: SPH - sodium perborate + 30% hydrogen peroxide; SPW - sodium perborate + distilled water; CP-37% carbamide peroxide; and CON-distilled water (control). The bleaching agents were replaced every 7 days, over 4 weeks. Following bleaching procedures, the groups were divided into four subgroups (n = 20), according to the post-bleaching times: 0 (baseline), 7, 14 and 21 days. After that, the cavities were restored with an adhesive system (Single Bond; 3M Co., St Paul, MN, USA) and a composite resin (Z100/3M). The specimens were thermocycled, stained with 2% methylene blue solution (pH 7), and sectioned longitudinally. The teeth were evaluated blind and independently by three previously calibrated examiners, to provide representative scores. The data were submitted to Kruskal-Wallis and multiple comparison tests (alpha=0.05). At baseline and 7 days, the SPH group showed a higher degree of dye penetration than the CON (P=0.04). At 14 and 21 days, there were no differences among groups. The association of sodium perborate with 30% hydrogen peroxide or with water may affect the sealing ability of composite resin restorations performed up to 7 days after bleaching procedures.

Caries progression and inhibition in human and bovine root dentine in situ

Since the use of bovine instead of human dentine to evaluate cariogenic and anticariogenic substances is not well established, this in situ study was conducted. Eleven volunteers wore palatal acrylic devices containing 4 dentine slabs (2 human and 2 bovine). Sucrose solution (20%) was dripped over all slabs 4 times a day, simulating a cariogenic challenge. Dentifrice slurries, fluoridated or not, were dripped over specified dentine slabs 3 times a day to evaluate caries reduction. After 14 days, the biofilm formed on the dentine slabs was collected for microbiological analysis. In dentine, mineral loss (DeltaZ) and lesion depth (LD) were determined by cross-sectional microhardness and by polarized light microscopy, respectively. The total streptococci and mutans streptococci counts in the biofilm formed either on human or on bovine slabs, whether treated or not with fluoride dentifrice, were not statistically different. The DeltaZ and the LD values of dentine treated with fluoride dentifrice were significantly lower than the values of dentine treated with non-fluoride dentifrice. The differences in the DeltaZ and LD values between the human and bovine dentine were not statistically significant. The results suggest that bovine dentine can be used instead of human to evaluate caries development and inhibition.

In situ microhardness evaluation of glass--ionomer/composite resin hybrid materials at different post-irradiation times

The purpose of this paper was to evaluate in situ the microhardness of a composite resin, two resin-modified glass-ionomers and two polyacid-modified composite resins at different post-irradiation times. The materials analysed were: Z 100/3M (Z1); Fuji II LC/GC Corporation (Fu); Vitremer/3M (Vi); Freedom/SDI (Fr); and Dyract/Dentsply (Dy). Palatal intra-oral acrylic resin appliances were made for each of the 24 volunteers in the experiment. In each appliance, a specimen of each material was fixed. Microhardness tests were performed at 30 min, 1, 2, 4, 8, 24 and 48 h, 7, 10, 14, 17 and 21 days after initial light-curing. The analysis of variance followed by the Tukey test showed significant differences of microhardness among all materials (Fu < Vi < Fr < Dy < Z1) up to 48 h. From the seventh to the fourteenth day, statistical differences were not found between Freedom and Dyract (Fu < Vi < Fr=Dy < Z1). On the seventeenth and twenty-first days, Vitremer, Freedom and Dyract did not present statistical differences, but differed from Fuji II LC and Z 100 (Fu < Vi=Fr=Dy < Z1). The polynomial regression showed an increase of microhardness over time for the glass-ionomers/composite resin hybrid materials, although there were differences of microhardness among these materials. There was no significant changes in microhardness levels for the composite resin over time.

Effect of storage media upon the surface micromorphology of resin-based restorative materials

The aim of this study was to evaluate the effect of different storage media upon the surface micromorphology of resin-based restoratives. One resin-modified glass-ionomer (Fuji II LC Improved), one polyacid-modified composite resin (Dyract AP), one microfilled composite resin (Durafill VS), and one hybrid composite resin (Filtek Z250) were tested. For each material, 45 standardized cylindrical specimens were randomly made. After 24 h, samples were finished and polished, and their surface roughness measured to obtain Ra (micro m) baseline values (Bv). Fifteen specimens of each material were then stored at 37 +/- 1 degrees C, for 24 h, either in distilled deionized water or in artificial saliva, or else subjected to a pH-cycling regimen. At the end of 10 days of storage, final readings (Fv) of surface roughness were obtained. The Analysis of Covariance (alpha=0.05), considering the covariate Bv showed a significant interaction between restorative materials and storage media (P value=0.0000). Multiple comparison Tukey's test revealed that the surface roughness of resin-based restoratives subjected to a pH-cycling model was significantly higher compared with both distilled deionized water and artificial saliva. Micromorphological changes were noticed in a situation of acid challenge.

Extent of the cariostatic effect on root dentin provided by fluoride-containing restorative materials

This study evaluated the extent of the cariostatic effect on root dentin provided by four fluoride-containing restorative systems: Ketac-Fil/ESPE [Ke], Fuji II LC Improved/GC Corp [Fj], Dyract AP/Dentsply [Dy] and SureFil/Dentsply [Su], and one without fluoride: Z250/3M [control]. Ninety-five bovine root dentin fragments (5.0 x 6.0 mm) were obtained, embedded in polyester resin and planed. Cavities (1.5 x 3.5 x 1.0 mm) were made and restored by the five restorative systems (n=19) in a randomized complete block design according to the manufacturers' instructions. After 24 hours, the dentin/restoration surface was polished. The restoration surface and an adjacent area of 3.0 x 3.0 mm were demarcated and submitted to a pH-cycling model. Dentin surface Knoop microhardness values were obtained (5.0-g, 5.0-s) for 10 distances: 50, 100, 150, 300, 600, 900, 1200, 1500, 1800 and 2100 microm from the margin of the restoration. The dentin microhardness means for each restorative material at each distance was considered by the ANOVA multi-factor split-plot method. The interaction between the restorative system and distance was statistically significant (p<0.05). The Tukey test and the regression analysis showed that the means of [Ke] and [Fj] were similar up to 300 microm, the [Ke] means being higher than the [control] at distances 50, 100, 150 and 300 microm. The [Fj] means were higher than the [control] at distances 50, 100 and 150 microm. The microhardness means of [Dy] and [Su] were not statistically different from the [control] and remained steady throughout the studied distances. This study concluded that the extent of the cariostatic effect on root dentin was 300 microm for [Ke] and 150 microm for [Fj]. [Dy] and [Su] did not show any cariostatic effect.

Radiopacity of esthetic restorative materials compared with human tooth structure

PURPOSE

To compare the radiopacity of 13 restorative materials, (a conventional glass-ionomer cement, three resin-modified glass-ionomer cements, six polyacid-modified resin-based composites, and three resin-based composites) to sound tooth structure.

MATERIALS AND METHODS

315 specimens were made of the restorative materials (n = 21), of 2 mm height and 4.1 mm diameter. Radiographs were taken of the specimens, together with the tooth structure sample and an aluminum step wedge. The radiopacity values of each specimen were taken using a transmission densitometer.

RESULTS

ANOVA and Tukey's test (95% level of confidence) revealed that, except for a resin-based composite, a polyacid-modified resin-based composite, a resin-modified glass-ionomer cement and the conventional glass-ionomer cement, all the evaluated restorative materials were more radiopaque than the tooth structure.

Efficacy of a dip slide test for mutans streptococci in caries risk assessment

The aim of this study was to evaluate the efficacy of a dip slide test for mutans streptococci in caries risk assessment, when the microbiological results were compared to well-defined clinical criteria (DCC) for caries risk, clinically measured through high and low caries activity. Eighty-one volunteers from the 6th to 8th grades from public schools of Piracicaba, São Paulo, Brazil, were evaluated for dental caries. All free smooth surfaces were evaluated to check whether or not there were white spots. Based on the subjects' caries experience, a calibrated clinician divided them into groups of high and low caries activity. The subjects were submitted to a salivary test (CARITEST SM) from the same batch number. Kappa statistics (kappa) were applied to verify the reproducibility of the simplified test, checked through interexaminer agreement when the results were classified by independent and blind means. The microbiological results were validated according to expressions of sensitivity and specificity. A moderate agreement was verified as the results were classified according to 6 scores (kappa=0.55), and the agreement was substantial when the results were classified according to high and low microbiological count (kappa=0.78). The sensitivity and specificity values were 0.59 and 0.85, respectively, showing that the test was more specific than sensitive, and could thus better identify the low caries risk subjects.

Surface roughness assessment of resin-based materials during brushing preceded by pH-cycling simulations

This study evaluated the surface roughness pattern of resin-based restorative materials during brushing preceded by a regimen that simulated a dynamic pH-cycling. Restoratives included two resin composites (Renamel Microfill and Charisma), two polyacid-modified composite resins (Compoglass-F and Dyract AP) and one resin-modified glass ionomer cement (Fuji II LC Improved). Twenty standardized cylindrical specimens of each material were prepared according to a randomized complete block design. After finishing and polishing, the average surface roughness (Ra) and profile-length ratio (LR) of the specimens were determined. The experimental units were subjected to a pH-cycling regimen, and then to 10,000 brushing strokes. New readings of both the Ra and LR parameters were obtained. The same protocol of pH-cycling, brushing simulation and surface roughness measurements were repeated 10 times. Data was analyzed using ANOVA according to split-plot design and Tukey's test. Results showed the pH-cycling followed by 10,000 brushing strokes provided a remarkable increase in Ra for all restorative materials except for Renamel. Throughout the brushing simulation, Renamel, Charisma, Compoglass-F and Dyract AP showed steady textures, whereas Fuji II LC Improved exhibited a progressive increase in surface roughness. Among the materials tested, Renamel presented the smoothest surface, followed by Charisma and Compoglass-F, which did not differ from each other except at the baseline. Dyract AP was different from both these materials except at the baseline. Fuji II LC Improved had the roughest surface texture.

The effect of 10% carbamide peroxide bleaching material on microhardness of sound and demineralized enamel and dentin in situ

This in situ study evaluated the microhardness of sound and demineralized enamel and dentin submitted to treatment with 10% carbamide peroxide for three weeks. A 10% carbamide peroxide bleaching agent--Opalescence/Ultradent (OPA)--was evaluated against a placebo agent (PLA). Two hundred and forty dental fragments--60 sound enamel fragments (SE), 60 demineralized enamel fragments (DE), 60 sound dentin fragments (SD) and 60 demineralized dentin fragments (DD)--were randomly fixed on the vestibular surface of the first superior molars and second superior premolars of 30 volunteers. The volunteers were divided into two groups that received bleaching or the placebo agent at different sequences and periods at a double blind 2 x 2 crossover study with a wash-out period of two weeks. Microhardness tests were performed on the enamel and dentin surface. The SE and DE submitted to treatment with OPA showed lower microhardness values than the SE and DE submitted to treatment with PLA. There were no statistical differences in microhardness values for SD and DD submitted to the treatment with OPA and PLA. The results suggest that treatment with 10% carbamide peroxide bleaching material for three weeks alters the enamel microhardness, although it does not seem to alter the dentin microhardness.

Radiopacity of glass-ionomer/composite resin hybrid materials

This study visually compared the radiopacity of seven restorative materials (3 resin-modified glass-ionomer cements, 3 polyacid-modified composite resins, and 1 conventional glass-ionomer cement) to a sound tooth structure sample, and an aluminium stepwedge. All hybrid materials were more radiopaque, except for one resin-modified glass-ionomer cement, than both the tooth structure and conventional glass-ionomer cement.

Effect of fluoride gels on micromorphology of resin-modified glass-ionomer cements and polyacid-modified resin composites

OBJECTIVE

The purpose of this study was to evaluate the surface micromorphology of resin-modified glass-ionomer cements and polyacid-modified resin composites subjected to a neutral sodium fluoride (NNaF) and an acidulated phosphate fluoride (APF) gel application.

METHOD AND MATERIALS

Thirty standardized cylindric specimens were randomly obtained from each of two resin-modified glass-ionomer cements-Fuji II LC Improved and Photac-Fil Aplicap-and two polyacid-modified resin composites--Dyract and F2000-amounting to 120 samples. After 1 week, the specimens were finished and polished with aluminum oxide disks. Surface treatments with fluoride gels, or distilled water as a control, were performed four times, interspersed with eight pH cycles, simulating high cariogenic challenges. Five calibrated evaluators assessed the surface micromorphology through photomicrographs.

RESULTS

The Kruskal-Wallis test showed no significant difference between the control and experimental groups for Fuji II LC Improved and Dyract. Photac-Fil Aplicap showed less micromorphologic change as a result of distilled water application, unlike the NNaF and APF treatments, which revealed no significant difference from each other. For F2000, there was no significant difference between the surfaces treated by NNaF and distilled water; the highest degradation occurred with the APF.

CONCLUSION

Both the resin-modified glass-ionomer cements and the polyacid-modified resin composites showed erratic behaviors concerning their micromorphology when subjected to fluoride gel application.

Effects of 10% carbamide peroxide bleaching materials on enamel microhardness

PURPOSE

To evaluate the microhardness of enamel treated with two different 10% carbamide peroxide bleaching materials at different time intervals.

MATERIALS AND METHODS

Two bleaching agents were analyzed: Opalescence (OPA) and Rembrandt (REM). The control group (CON) consisted of dental fragments maintained in artificial saliva. Bleaching was accomplished for 8 hrs per day and stored during the remaining time in an individual recipient with artificial saliva. Enamel microhardness testing was performed before the initial exposure to the treatments and after 1, 7, 14, 21, 28, 35 and 42 days.

RESULTS

The ANOVA, followed by the Bartlet and Tukey tests, showed significant differences for treatments (P < 0.00001) from day 7-day 42. From the 7th to the 14th day, OPA presented an increase of enamel microhardness over time while REM presented a decrease of microhardness. Statistical differences were not found between REM and the control group (OPA > CON = REM). From the 21st-35th day, enamel fragments bleached with OPA and REM presented a decrease of microhardness. Statistical differences of microhardness were verified among all the treatments (OPA > CON > REM). On the day 42, statistical differences were not found between OPA and the control group, but they were found between REM and the control group (OPA = CON > REM). The polynomial regression showed an increase of microhardness for OPA until the 21st day, followed by a decrease of microhardness up to the 42nd day. A decrease of microhardness for REM was verified. There were alterations in enamel microhardness as a function of bleaching time when using the two different 10% carbamide peroxide whiteners. Over a 42-day treatment time, bleaching with REM agent caused a decrease in enamel microhardness. The OPA agent initially increased the microhardness, then returned to the control level. Different bleaching materials with the same concentration of carbamide peroxide have different effects on the enamel.

"Train surfers": analysis of 23 cases of electrical burns caused by high tension railway overhead cables

The term "train surfers" describes a group of adolescents from the outskirts of the city of Rio de Janeiro, who are compelled by the overcrowded railway trains to travel on the roofs of the wagons. Collision with electrical high-tension wires is a relatively frequent occurrence, causing extensive and complex injuries. This study analyzes this clinical and surgical phenomenon which has caused over 100 fatalities in more than 200 registered accidents over the past 10 years.

Effectiveness of surface protection for resin-modified glass-ionomer materials

OBJECTIVE

The purpose of this study was to evaluate the effectiveness of various surface treatments for resin-modified glass-ionomer restorative materials by determining dye uptake spectrophotometrically.

METHOD AND MATERIALS

Two hundred twenty-four specimens, 4.1 mm in diameter and 2.0 mm thick, were made of 3 materials: Vitremer, Fuji II LC, and Photac-Fil Aplicap. Specimens were divided into 15 groups. The positive and negative control specimens remained unprotected, while the experimental specimens were protected with Heliobond light-activated bonding resin, Colorama nail varnish, or surface coatings indicated by the manufacturers of the glass-ionomer materials: Finishing Gloss for Vitremer, Fuji Varnish for Fuji II LC, and Ketac Glaze for Photac-Fil. The disks were immersed in 0.05% methylene blue for 24 hours except for the negative control group, which was immersed in deionized water. After 24 hours, the disks were removed, washed, and individually placed in 1 mL of 65% nitric acid for 24 hours. The solutions were centrifuged and the spectrophotometric absorbance was determined at 606 nm. The dye uptake was expressed in micrograms of dye per milliliter, and the results were analyzed with the Kruskal-Wallis test.

RESULTS

There were no differences in dye uptake among the 3 resin-modified glass-ionomer restorative materials; however, all of them required surface protection.

CONCLUSION

The best surface protection for the 3 evaluated materials was obtained with Heliobond light-activated bonding resin.

Occlusal caries: diagnosis and noninvasive treatments

The diagnosis of occlusal caries and the initiation of more effective treatment present a considerable challenge. Caries not only has decreased in prevalence, but also has changed in pattern and in progression because of the increased use of fluorides. Correct diagnosis is crucial, distinguishing lesions that can be arrested by noninvasive treatment from those that may justify restorative treatment. For incipient lesions, it is necessary to improve the patient's home care preventive methods, to apply fluoride or other prophylactic agents, or even to seal fissures, preserving the maximum amount of sound tooth structure. This article discusses the diagnosis of occlusal caries and noninvasive treatments for the management of early caries.

In vitro microleakage of glass-ionomer composite resin hybrid materials

The purpose of this study was to evaluate the microleakage of six glass-ionomer composite resin hybrid materials compared with a glass-ionomer cement and a composite resin. Standardized class 5 dentin cavities were prepared on root surfaces of 240 extracted human teeth that were randomly assigned to eight groups and restored using the following restorative systems: (I) Vitremer, (II) Compoglass, (III) Photac-Fil Aplicap, (IV) Variglass, (V) Dyract, (VI) Fuji II LC, (VII) Ketac-Fil Aplicap, and (VIII) Z100. The teeth were thermocycled, placed in a 2% methylene blue solution, and sectioned with diamond disks. Dye penetration was scored on a scale of 0-3. Results showed no significant differences among groups VIII, IV, I, V, VI, III, and II. There were also no significant differences among groups VI, III, II, and VII.

Volumetric microleakage assessment of glass-ionomer-resin composite hybrid materials

OBJECTIVE

This study was intended to quantify the marginal leakage of three glass-ionomer-resin composite hybrid materials and compare it with the leakage exhibited by a glass-ionomer cement and a bonded resin composite system.

METHOD AND MATERIALS

Standardized Class V cavities were prepared on root surfaces of 105 extracted human teeth, randomly assigned to five groups of 21 each, and restored with either Ketac-Fil Aplicap, Z100/Scotchbond Multi-Purpose Plus, Vitremer, Photac-Fil Aplicap, or Dyract. The teeth were thermally stressed for 500 cycles and stained with methylene blue. The microleakage was quantified spectrophotometrically, and the data were statistically analyzed with Friedman's test.

RESULTS

There were no significant differences in microleakage among the five groups. Restorations of all tested materials showed some marginal leakage in Class V cavities.

CONCLUSION

The microleakage performance of glass-ionomer-resin composite hybrid materials was similar to those of a conventional glass-ionomer and a bonded resin composite system.

Inhibition of demineralization in vitro around amalgam restorations

OBJECTIVE

The purpose of this in vitro study was to evaluate some forms of preventing or avoiding demineralization within enamel cavity walls adjacent to amalgam restorations.

METHODS AND MATERIALS

Third molar teeth were sectioned to obtain 72 specimens, divided into one control and five experimental groups: amalgam only; varnish plus amalgam; acidulated phosphate fluoride plus amalgam; adhesive amalgam; glass-ionomer cement plus amalgam; control (amalgam only, not subjected to a demineralization challenge). The experimental groups were subjected to PH and thermal cycling and then submitted to enamel hardness determinations.

RESULTS

Significant differences between the treatment groups revealed that the bonded amalgam technique offered the best resistance to demineralization. The use of cavity varnish resulted in greater mineral loss than amalgam placed alone.

CONCLUSION

The use of an adhesive system, glass-ionomer cement, or acidulated phosphate fluoride under amalgam restorations may interfere with development of secondary caries.

First Report of Potato Tuber Necrotic Ringspot Disease Caused by PVYNTN in Portugal

During the last 2 years, potato (Solanum tuberosum L.) tubers displaying superficial necrotic arcs and rings were found in central Portugal. These symptoms increased during storage, and diminished tuber quality of ware (fresh-market) potatoes; however, no internal necrosis, which is typical for infections caused by tobacco rattle virus or potato mop top virus, was observed. The symptoms led to the preliminary diagnosis of potato tuber ringspot disease (PTNRD), caused by a tuber necrosis (TN)-inducing isolate of the tobacco veinal necrosis strain group of potato virus Y (PVY^N) that was named PVY^NTN. The occurrence of PVY^NTN has been reported by a number of European countries. Suspect PTNRD tubers of the cv. Monalisa were obtained from several Portuguese potato growers and were tested with polyclonal antibodies (pabs) that reacted generally with PVY, and with monoclonal antibodies (mabs) raised against PVY^N. Serogical tests were carried out in a double antibody sandwich (DAS) enzyme-linked immunosorbent assay (ELISA) with pabs and in a triple antibody sandwich (TAS) ELISA when mabs were used. As a result, the tubers were found to be infected with a virus isolate belonging to the PVY^N strain group. Since PVY^NTN cannot be distinguished serologically from other members of the PVY^N strain group due to the similarities of their coat proteins (1), reverse transcription-polymerase chain reaction combined with immunocapture was applied for diagnostic purposes. The olignucleotide primers used were located in the 5' non-coding region at nucleotide 103 and in the adjacent P1 protein gene coding region at position 919. This primer pair can be used to distinguish PVY^NTN from other members of the PVY^N strain group (2). Tests were carried out with plant sap from tubers and from plants grown from eye-cuttings and also from tobacco plants that were inoculated with plant sap of these potato tubers and plants. Control samples included sap from un-infected tobacco plants and from tobacco plants infected with a PVY^N isolate and with the PVY^NTN type strain "Hungary". The expected amplification product of 835 bp appeared in the agarose gel with samples originally obtained from the tubers and with the PVY^NTN control but not with the PVY^NTN control, indicating that the tuber symptoms in potato cv. Monalisa were caused by infections with PVY^NTN. This is the first report of the occurrence of PVY^NTN in Portugal. References: (1) T. Dalmay and E. Balazs. Nucleic Acids Res. 18: 6721, 1990. (2) H. L. Weidemann and E. Maiss. Z. Pflanzenkr. Pflanzenschutz 103:337, 1996.

Surface finishing of glass ionomer

PURPOSE

To evaluate the surface roughness and staining of a glass ionomer cement when subjected to different finishing procedures.

MATERIALS AND METHODS

Sixty-four discs of Chem-Fil II glass ionomer cement were submitted to staining test with methylene blue by spectrophotometry and roughness test by profilometry. Four groups were evaluated: Mylar matrix (control). Sof-Lex discs, Enhance points, and diamond bur.

RESULTS

Staining and roughness test, analyzed by ANOVA and Tukey's test, showed that the best surface was obtained when the material cured in contact with the Mylar matrix strip or when treated with Sof-Lex discs. The poorest results were obtained after using the diamond bur.

Glass ionomer cement surface protection

PURPOSE

To evaluate the effectiveness of various surface treatments for glass ionomer cement (GIC) by determining quantity of dye uptake spectrophotometrically.

MATERIALS AND METHODS

Sixty specimens, 4.5 mm diameter and 2 mm thick, were made from Shofu GIC and divided into 10 groups. Positive control (A) and negative control (B) specimens were not protected while experimental specimens were protected with ARM chemically-cured bonding resin (C), Durafill Bond light-cured bonding resin (D), Bondlite light-cured bonding resin (E), Colorama nail varnish (F), Shofu varnish (G), Copalite varnish (H), Vaseline (I) or Vaseline followed by Copalite (J). The discs were immersed in 0.05% methylene blue solution 10 minutes after mixing except group B specimens which were immersed in deionized water. After 24 hours the discs were removed, washed, and individually placed in 1 ml 65% nitric acid for 36 hours. The solutions were filtered, centrifuged and the absorbance determined spectrophotometrically at 590 nm. Dye uptake was expressed in microgram dye/restoration and the data analyzed by ANOVA and Tukey Kramer test.

RESULTS

The mean (SD) of dye uptake were: A:95.12 (11.28); B:0 (0); C:40.90 (5.06); D:33.89 (3.63); E:35.73 (3.36); F:3.29 (0.79); G:14.87 (2.86); H:21.99 (3.25); I:47.21 (7.06); J:29.74 (3.49). All the surface agents were effective in protecting setting restorative glass ionomer cement, but nail varnish provided the best results.

Effect of substance P on superoxide anion and IL-8 production by human PMNL

The neuropeptide substance P (SP), a main mediator of neurogenic inflammation, has been shown to have direct and modulatory effects on functional responses of polymorphonuclear leucocytes (PMNL). In this study, we further investigated the effects exerted by SP on human PMNL functions. Pretreatment of PMNL with SP resulted in an increase of superoxide anion (O2-) production in response to formyl-methionyl-leucyl-phenylalanine (FMLP), concanavalin A (Con A) and opsonized zymosan (STZ). In contrast, the O2- production induced by tumour necrosis factor (TNF) was strongly inhibited by pretreatment with SP. Both enhancement and inhibition of O2- response were exerted by SP in a dose-dependent manner and at concentrations which did not directly stimulate O2- production. These effects were rapid in onset, and occurred after 5 min of preincubation of cells with the neuropeptide. At concentrations that modulated O2- production by PMNL, SP also directly stimulated release of the chemotactic cytokine interleukin-8 (IL-8). Induction of IL-8 release required a longer incubation time (1 hr) with SP and was preceded by an increase of IL-8 mRNA steady-state levels. Furthermore, as well as directly stimulating IL-8 production, SP was also able to enhance the IL-8 release induced by other stimuli such as FMLP and TNF. The results of this study indicate that, in addition to the rapid and differential modulation of O2- production, SP also induces long-term changes such as IL-8 synthesis and release, and can thus amplify the process of PMNL recruitment to the inflammatory site.

Ligation of members of the beta 1 or the beta 2 subfamilies of integrins by antibodies triggers eosinophil respiratory burst and spreading

Eosinophils interact with extracellular matrix proteins and endothelial cells through adhesion proteins belonging to the beta 1 and beta 2 subfamilies of integrins. Extending previous observations, we found that tumour necrosis factor (TNF) and granulocyte-macrophage colony-stimulating factor stimulated generation of superoxide anion by eosinophils plated on fibronectin-coated surfaces. As studies with adherent neutrophils indicated that TNF might act as activating leucocyte integrins to deliver signals involved in activation of cell functions, we investigated the effects of monoclonal antibodies (mAb) directed against VLA-4 (CD49d/CD29), LFA-1 (CD11a/CD18), CR3 (CD11b/CD18) or the common beta 2 subunit (CD18) on generation of eosinophil toxic oxygen molecules and spreading. We show that cross-linking of members of both the beta 1 and the beta 2 integrin subfamilies triggers eosinophil respiratory burst and spreading. Evidence for the selectivity of anti-integrin mAb effects is derived from the findings that isotype-matched mAb of other specificities (anti-class I MHC Ag, anti-beta 2-microglobulin, anti-CD4) did not trigger eosinophil functions. The findings presented in this paper suggest that integrin-dependent, eosinophil adhesion in sites of allergic reaction may be accompanied by release of toxic oxygen molecules involved in tissue damage.

Factor-specific changes in oxidative burst response of human neutrophils in skin-window exudates

Human neutrophils were isolated from blood and aseptic inflammatory exudates. The respiratory burst response was measured as superoxide (O2-) production by a microplate assay system and polarographically as oxygen consumption. Exudate cells exhibited a respiratory burst in response to n-formyl-methionyl-leucyl-phenyl-alanine (FMLP) that was two- to threefold higher than the burst exhibited by peripheral blood cells. The O2- production induced by substance P was also found to be fivefold higher in exudate cells, while the metabolic response to other stimulants such as concanavalin A (con A), phorbol-myristate acetate (PMA), NaF, and immunocomplexes was not primed. Serum-treated zymosan (STZ)-stimulated activity was primed by only 11%. In contrast, superoxide production in response to tumor necrosis factor-alpha (TNF) was decreased in exudate versus blood cells by about 50%. Therefore, the skin-window cells, compared to blood cells, appear to be at the same time primed, unmodified, and desensitized, according to the different stimulants employed.

In situ anticariogenic potential of glass ionomer cement

The purpose of this study was to compare the amount of fluoride in plaque formed on glass ionomer cement or composite and to evaluate the effects of fluoride released on growth of cariogenic microflora, fluoride uptake, and secondary caries formation under in situ conditions of a high cariogenic challenge. Ten adult volunteers took part in this crossover study performed in two phases of 28 days. Eighty enamel blocks were randomly restored with glass ionomer cement (Chelon-Fil-Espe) or composite (Silux). During each phase of the study, an acrylic resin appliance, containing four enamel blocks restored with the same material, was constructed for each of the volunteers. During the experimental period, all subjects used fluoride-free dentifrice, refrained from brushing the restored enamel blocks, and immersed the appliances into 20% sucrose solution eight times a day. Fluoride levels, mutans streptococci, and lactobacilli were assessed in dental plaque. Fluoride uptake and microhardness profiles were determined in enamel around the restorations. Statistical analyses indicated a significantly higher level of fluoride (p < 0.05) and a lower level of mutans streptococci plaque formed on glass ionomer cement. Analysis of variance in a split-plot model indicated that in the enamel around the glass ionomer restoration the fluoride uptake was significantly greater (p < 0.025) and the mineral loss significantly lower (p < 0.01). The results show that glass ionomer cement presents a broad anticariogenic effect and may be of value in preventing secondary caries, even under conditions of a high caries risk.

The in vitro effect of glass-ionomer cement restoration on enamel subjected to a demineralization and remineralization model

The purpose of this in vitro study was to evaluate differences in initiation and progression of carieslike lesions around restorations in enamel. A demineralization/remineralization cycling model was used to induce experimental secondary caries around cavities restored with glass-ionomer cement or composite resin. The effects of these materials were compared by microhardness profiles. The results indicated that glass-ionomer cement showed potential value as a restorative material for the prevention or reversal of caries in enamel adjacent to restorations, even in situations of high cariogenic challenge.

Studies on the NADPH oxidase of phagocytes. Production of a monoclonal antibody which blocks the enzymatic activity of pig neutrophil NADPH oxidase

We describe in this paper a monoclonal antibody to pig NADPH oxidase which inhibits enzymatic activity. This antibody, designated 1H8.2, was selected from a group of monoclonal antibodies produced against active preparations of purified NADPH oxidase and which showed selectivity of binding. 1H8.2 is an IgM restricted in binding to pig NADPH oxidase and showing higher binding to NADPH oxidase purified from phorbol myristate acetate-stimulated than from resting neutrophils. The antibody inhibits by about 90% the oxidase activity at 20-50 micrograms/ml. Inhibition is due to a decrease of the Vmax of the oxidase, and the Km is not affected. Incubation of the NADPH oxidase with 1H8.2 in the presence of concentrations of NADPH up to 25-fold the Km does not prevent the inhibition. Together with the evidence that the antibody does not inhibit the neutrophil superoxide dismutase-insensitive NADPH cytochrome c reductase and the liver NADPH-cytochrome c reductase this observation indicates that the 1H8.2 does not bind to an epitope belonging to the NADPH-binding site. Experiments of immunoprecipitation of iodinated membrane proteins and of immunoaffinity purification showed that 1H8.2 recognizes a heterodimer of apparent molecular mass of 16/18 and 14 kDa. These polypeptides can be involved in the NADPH oxidase activity or represent still unrecognized molecules able to modulate its function.

Immunologic assessment determined by response to IL-2 and immunophenotyping of tumor-infiltrating lymphocytes, of invaded and non invaded lymph nodes and of peripheral blood lymphocytes from twenty-one patients with primary laryngeal cancer

The aim of the study was to identify the lymphocyte sets and/or subsets possibly involved in the response to malignant cells. For this purpose we have investigated both the cells at the tumor site, i.e. tumor-infiltrating lymphocytes (TIL), and the cells present in the draining lymph nodes, either invaded or non invaded, as well as the peripheral blood lymphocytes from twenty-one patients with primary laryngeal epidermoid carcinoma. The functional assay was carried out by the proliferative response to mitogens, to Interleukin 2 and to their association, the surface immunophenotyping was performed with a large panel of monoclonal antibodies. TIL are the most responsive cells to mitogens, while the responsiveness of TIL and of LN cells to IL-2 was in the same range. PHA-activated TIL are the most responsive cells to IL-2. Our data indicate that TIL do show in vitro, and probably also in vivo, "activation" with elevated responsiveness to IL-2. The surface phenotype showed a strikingly increased proportion of T8+ cells in TIL as compared to T8+ cells in all types of LN, thus confirming within TIL variable, but high, proportions of clones which display cytolytic activity, possibly induced by IL-2. Our data seem to support the perspective for a therapeutic approach in vivo with IL-2, which via its influence on TIL, may act on tumor cells.

Activation of human neutrophils by substance P. Effect on oxidative metabolism, exocytosis, cytosolic Ca2+ concentration and inositol phosphate formation

The neuropeptide substance P (SP), which has been suggested to mediate neurogenic inflammation, induces in human neutrophils the activation of the respiratory burst measured as O2 consumption and H2O2 production, and a cytochalasin B-dependent secretion of specific and azurophilic granules. The SP(4-11) fragment is much more stimulant than the entire molecule, whereas the SP(1-4) fragment is inactive. The respiratory and secretory response to SP are associated with an activation of phosphoinositide turnover, of Ca2+ influx and release from intracellular stores. Pertussis toxin inhibits 70% of the respiratory response and the residual 30% activity remains, even increasing 10-fold the concentration of the toxin. 1-(5-Isoquinolinesulfonyl)-2-methylpiperazine, a putative inhibitor of protein kinase C, does not modify the respiratory response to SP. Cytochalasin B significantly depresses the activation of the respiration by SP, whereas it moderately enhances the activation of phosphoinositide turnover and potentiates the increase of intracellular Ca2+ concentration. The results are discussed in relation to the receptor apparatus involved in SP activity, the signal transduction sequence activated by SP for the stimulation of NADPH oxidase, and the role of cell response to SP in the inflammatory process.

Activation of human neutrophils by substance P. Effect on oxidative metabolism, exocytosis, cytosolic Ca2+ concentration and inositol phosphate formation

The neuropeptide substance P (SP), which has been suggested to mediate neurogenic inflammation, induces in human neutrophils the activation of the respiratory burst measured as O2 consumption and H2O2 production, and a cytochalasin B-dependent secretion of specific and azurophilic granules. The SP(4-11) fragment is much more stimulant than the entire molecule, whereas the SP(1-4) fragment is inactive. The respiratory and secretory response to SP are associated with an activation of phosphoinositide turnover, of Ca2+ influx and release from intracellular stores. Pertussis toxin inhibits 70% of the respiratory response and the residual 30% activity remains, even increasing 10-fold the concentration of the toxin. 1-(5-Isoquinolinesulfonyl)-2-methylpiperazine, a putative inhibitor of protein kinase C, does not modify the respiratory response to SP. Cytochalasin B significantly depresses the activation of the respiration by SP, whereas it moderately enhances the activation of phosphoinositide turnover and potentiates the increase of intracellular Ca2+ concentration. The results are discussed in relation to the receptor apparatus involved in SP activity, the signal transduction sequence activated by SP for the stimulation of NADPH oxidase, and the role of cell response to SP in the inflammatory process.