New fluxon resonant mechanism in annular Josephson tunnel structures

A novel dynamical state has been observed in the dynamics of a perturbed sine-Gordon system. This resonant state has been experimentally observed as a singularity in the dc current-voltage characteristic of an annular Josephson tunnel junction, excited in the presence of a magnetic field. In this respect it can be assimilated to self-resonances known as Fiske steps. Differently from these, however, we demonstrate, on the basis of numerical simulations, that its detailed dynamics involves rotating fluxon pairs, a mechanism associated, so far, to self-resonances known as zero-field steps. This occurs because the size of nonlinear excitations is comparable with that of the system.

Selection for aneuploid potato hybrids combining a low wild genome content and resistance traits from Solanum commersonii

A breeding scheme based on the production of progenies with odd ploidy was followed to introduce useful genes from the wild Solanum commersonii (cmm) into S. tuberosum (tbr) genome. Hybrids from 5 x x 4 x crosses were characterized for traits of interest, and selection was assisted by amplified fragment length polymorphism (AFLP) analysis. As expected, most of the hybrids were aneuploids, with a trend towards a low degree of aneuploidy. Despite the fact that aneuploidy has often been associated with a reduction in male and female fertility, most of the hybrids were fertile following crosses with tbr, making it possible to produce viable offspring. A screening for resistance traits deriving from cmm was also carried out. With respect to freezing resistance, the killing temperatures of cold-acclimated genotypes were distributed between the wild and cultivated parental values, with some hybrids displaying an acclimation capacity higher than 3 degrees C. A wide variability was also found for tuber soft rot resistance, and hybrids with high levels of resistance were identified. Selection of hybrids was based on a two-stage scheme that consisted of conventional phenotypic selection followed by an estimation of the wild genome content still present in order to identify hybrids combining noteworthy traits with a low wild genome content. Previously selected cmm-specific AFLPs were used to monitor the degree of wild genome content still present in each hybrid. The percentage of cmm-specific markers ranged from 59% to 91%, with an average value of 75%. AFLP analysis was employed to assist in the selection of valuable hybrids for further breeding efforts.

Dynamical control of macroscopic quantum tunneling

We show that the quantum Zeno and anti-Zeno effects are realizable for macroscopic quantum tunneling by current-bias modulation in Josephson junctions (and their analogs in atomic condensates).

Glycoalkaloids and acclimation capacity of hybrids between Solanum tuberosum and the incongruent hardy species Solanum commersonii

F(1) and backcross hybrids between sexually incompatible species Solanum commersonii and Solanum tuberosum were characterized for glycoalkaloid content and capacity to cold acclimate. Glycoalkaloid (GA) analysis revealed that F(1) triploids and BC(1) pentaploids contained the glycoalkaloids of both parents. In BC(2) (near) tetraploids the situation was different, in that some hybrids produced the GAs of both parents, whereas others contained only the GAs of S. tuberosum. This suggested that the GAs from S. commersonii may be lost rapidly, and that they may have a simple genetic control. The total tuber GA content of BC(1) and BC(2) groups averaged quite acceptable levels (165.9 mg/kg in BC(1) and 192.8 mg/kg in BC(2)), with six genotypes having a GA content <200 mg/kg fresh weight. The F(1) triploid hybrids expressed a capacity to cold acclimate similar to S. commersonii, whereas BC(1) and BC(2) genotypes generally displayed an acclimation capacity higher than the sensitive parent but lower than S. commersonii. However, one BC(1) and two BC(2) genotypes with an acclimation capacity as high as S. commersonii were identified. The polar lipid fatty acid composition in S. commersonii and its hybrid derivatives showed that, following acclimation, there was a significant increase in 18:3. Correlation analysis between the capacity to cold acclimate and the increase in 18:3 was significant, suggesting that the increase in 18:3 can be used as a biochemical marker for the assisted selection of cold-acclimating genotypes in segregating populations.

Intrinsic d-wave effects in YBa(2)Cu(3)O(7-delta) grain boundary Josephson junctions

We have measured the angular dependence of the Josephson critical current density (J(C)) in c-axis tilt biepitaxial grain boundary YBa(2)Cu(3)O(7-delta) junctions. We observe for the first time intrinsic d-wave pairing symmetry effects manifested as an oscillatory dependence of J(C) on angle. This intrinsic effect is evident even though spontaneous currents, possibly induced by faceting or barrier impurities, are observed in the grain boundaries.

Effects of CO2 laser treatment on fibroblast attachment to root surfaces. A scanning electron microscopy analysis

BACKGROUND

The aim of this study was to analyze the CO2 laser effects on root surfaces affected by periodontal disease in comparison to scaling and root planing for fibroblast attachment.

METHODS

Thirty single-rooted human teeth extracted because of advanced periodontal disease were included in this study. A total of 60 specimens, obtained from all selected teeth, were randomly assigned to 3 groups: 1) control (untreated); 2) hand scaling and root planing (SRP); or 3) laser (CO2 defocused pulsed) and ultrasonic scaling. All the specimens were incubated in Petri dishes with fibroblast suspension, and then observed by scanning electron microscopy (SEM).

RESULTS

The control group showed the lowest number of attached cells, with no tightly attached fibroblasts. The laser plus scaling group showed the highest number of attached fibroblasts, with the tightly attached fibroblast prevailing. The laser-treated and scaled root specimens did not show any damage or morphologic alteration of the root surfaces.

CONCLUSION

CO2 laser treatment in defocused, pulsed mode with a low power of 2W combined with mechanical instrumentation constitutes a useful tool to condition the root surface and increase fibroblast attachment to root surfaces.

Root surface morphological changes after focused versus defocused CO2 laser irradiation: a scanning electron microscopy analysis

BACKGROUND

Many studies have observed damages to root surfaces treated by CO2 laser in continuous mode with a focused beam. The morphologic changes observed were always associated with temperature increase induced by high energy release.

METHODS

The purpose of this study was to analyze by scanning electron microscopy (SEM) the effects of CO2 laser in 2 different modes on root surfaces. Study samples consisted of 30 extracted single-rooted periodontally compromised human teeth. Root specimens were randomly assigned to 3 groups: group A (12) treated with CO2 laser in continuous mode with a focused beam of 0.8 mm; group B (12) treated with CO2 laser in pulsed mode with defocused beam of 4 mm; and group C (6), untreated controls.

RESULTS

Group A (continuous mode) showed severe damages to dentin surfaces such as craters and fissures. Group B (defocused mode) did not result in any damages to the root surfaces, showing flat and smooth surfaces with apparent fusion of the smear layer and dentinal tubules almost completely sealed. The untreated control group was characterized by irregular and amorphous surfaces with several shallow depressions.

CONCLUSIONS

Although both laser modes resulted in changes to the treated root surface specimens, the changes resulting in a smooth surface from use of defocused pulsed beam may present an advantage in periodontal treatment.

Evidence for tetrasomic inheritance in a tetraploid Solanum commersonii (+) S. tuberosum somatic hybrid through the use of molecular markers

In order to assess the potential for interspecific recombination between the cultivated Solanum tuberosum (tbr) and the sexually isolated wild species Solanum commersonii(cmm), genetic analysis of a F(2) progeny obtained by selfing one tetraploid cmm (+) tbr somatic hybrid was performed through molecular markers. For this purpose, the extent of disomic and/or tetrasomic inheritance of species-specific RAPD and AFLP markers was determined by following their segregation in a 90-genotype progeny, and testing all the possible segregation ratios in a selfed tetraploid progeny. The RAPD analysis performed using 16 primers revealed that the cmm-specific RAPDs were mainly (93.7%) duplex markers and were equally distributed between loci with a disomic (46.7%) and tetrasomic (53.3%) inheritance. The AFLP analysis led to the identification of 272 (58%) informative AFLPs, which were either cmm- or tbr-specific markers. About 63% of cmm-specific AFLPs were duplex loci, most of which (92.6%) were inherited as tetrasomic loci. As regards the tbr-specific AFLPs, the percentage of simplex loci (52.9%) was higher than that of duplex loci (32.6%), and among the latter most (88.5%) were inherited as tetrasomic loci. Overall, 130 duplex markers were found, of which 53.1% were cmm-specific and 46.9% were tbr-specific. Out of 130 markers, 18 (13.8%) were inherited as disomic, and 112 (86.2%) as tetrasomic, loci. This implies that the majority of duplex markers were located on chromosomes which at meiosis tend to randomly pair as bivalents or to form tetravalents. The total number of simplex loci was 119, and most of them (82.3%) were tbr-specific loci. In some cases the observed segregation ratios even allowed us to clearly determine whether a random chromosome or chromatid segregation was detected. This was the case of three cmm-specific RAPDs, 19 cmm- and 25 tbr-specific AFLPs, which fit a 20.8:1 or 2.5:1 ratio, both cases for which a clear random chromatid segregation can be assumed, since they represent the limit of segregation expected when the distance between the locus and the centromere always leads to a cross-over event. The percentage of ascertained crossing-over events was around 37% out of the tetrasomically inherited loci clearly identified (128 loci), a value indicating that the flow of genes from the sexually isolated S. commersonii to the cultivated potato is possible, for at least a large proportion of genes.

Pharmacological and dietary prophylaxis and treatment of acute actinic esophagitis during mediastinal radiotherapy

Our purpose was to evaluate a pharmacological and dietary protocol of prophylaxis and treatment of acute actinic esophagitis during mediastinal radiotherapy. This phase II study was conducted on 29 patients affected by cancer not directly involving the esophagus. The irradiated volume included at least 10 cm of esophagus with a median dose of 46 Gy and the incidence of clinical acute esophagitis was scored with RTOG-EORTC tables. During the entire course of radiation therapy all patients were subjected to prophylaxis pharmacological therapy in addition to dietetic rules commonly used. All patients were evaluable, 9 (31%) had no acute esophageal toxicity, 20 (69%) had toxicity of degree 1, and no patient showed a toxicity of degree 2, 3, or 4, there were no toxicity-related related interruptions of the radiotherapy course. In conclusion, this low cost protocol seems to reduce the incidence and degree of acute radiation esophagitis (without added morbidity), compared with literature reports.

Evaluation and use of plant biodiversity for food and pharmaceuticals

Many epidemiological studies have shown the importance of fruit and vegetables in the human diet so as to prevent the onset of cardiovascular disease and several forms of cancer. The use for food and pharmaceuticals of two of the most widely grown and genetically well-known species in the world, the tomato and the potato, is reviewed. Tomatoes are important sources of vitamin C, potassium, folic acid and carotenoids such as lycopene and beta-carotene. It has been demonstrated that lycopene has anti-oxidant properties and interferes with the growth of cancerous cells. At the Department of Agronomy and Plant Genetics in Portici, interesting results have been obtained with the constitution of stable tomato hybrids having a high content of lycopene and vitamin C. Many of the parental lines used in constituting the hybrids come from interspecific crosses. Potato is also very important in the human diet for its content of high quality proteins, mineral salts and vitamins and it has many medicinal properties. The use of diploid wild species to transfer traits such as high content of vitamin C, mineral salts and high quality proteins into the cultivated potato through ploidy manipulation is discussed.

[Implants in partially edentulous patients with history of periodontal disease]

BACKGROUND

Microbiota associated with periodontal diseases were also associated with periimplant diseases. The purpose of this study was to determine the clinical status and composition of subgingival microbiota of implants and natural teeth in a group of partially edentulous patients with history of periodontal disease.

METHODS

38 partially edentulous patients with history of periodontal disease, treated with dental implants, were selected for this study. Patients selected for the study were in good health condition and did not take any antibiotics in the last six months. One year after second stage surgery a total of 72 implants and 38 teeth underwent clinical and microbiological examination. Clinical parameters were PD, PAL, PI and GI. Subgingival plaque samples were analyzed by dark-field microscopy and cultural analysis.

RESULTS

Clinical parameters didn't show any significant differences between periodontal and periimplant tissues. Dark-field microscopic examination showed higher prevalence of rods and spirochetes around implants than around teeth. There were no differences detected by cultural examination in the subgingival microbiota at peri-implant and periodontal sites.

CONCLUSIONS

Findings from this study showed no differences between implants and teeth in partially edentulous patients with history of periodontal disease one year after second stage surgery. Implants were colonized by microbiota similar to that observed around teeth and were well-maintained in patients with a history of periodontitis.

[New methods of percutaneous closure of patent ductus arteriosus]

Various devices have been developed for the percutaneous closure of persistent patent ductus arteriosus (PDA). In recent years Gianturco coils have become increasingly widespread for this purpose. Poor control during positioning is a major disadvantage of Gianturco coils, with resultant embolization of coils and residual shunts. Very recently a new screwing detachable coil is available (Cook Cardiology, Europe). Between January 1996 and January 2000, 34 consecutive patients with PDA underwent cardiac catheterization. Thirty cases were judged suitable for this procedure, on the base of diameter and morphology of the ductus. Three cases were excluded because of the ductal diameter was too large (> 4.2 mm) and one because of its morphology (type B). In 28 patients a single coil was positioned, while in one case 2 coils were simultaneously used. In 29 cases (97%) complete closure was obtained (in 18 cases immediately, in 6 after 24 hours, in 5 after 1 month). One case showed a residual shunt and a second coil was applied eighteen months later with complete closure. So, considering also this last case, the closure was achieved in 100%. There were neither embolization or other complications. In conclusion, screwing detachable coil for PDA closure is a safe, very effective and at low cost technique. Therefore nowadays this procedure represents the method of choice for occlusion of small PDA (minimal diameter < or = 4 mm).

Tetracycline fibres used to control bacterial infection during guided tissue regeneration (GTR)

AIMS

The colonization of suspected periodontal pathogens during the healing of periodontal defects treated by guided tissue regeneration (GTR) with e-PTFE membranes and tetracycline fibers was investigated.

METHODS

Fifteen patients, each with one pair of angular periodontal bone defects of comparable size and morphology were recruited for the study. In a matched-pair study design, the test defects were treated with e-PTFE membranes in combination with tetracycline fibers, while control defects were treated with e-PTFE membranes alone. Microbiological specimens were taken from control as well as from test sites preoperatively (T0), intraoperatively (T1), two weeks after surgery (T2) and from membranes at time of removal (T3). Cultural methods were used to identify the following species: Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi), Fusobacterium nucleatum (Fn) and Actinobacillus actinomicetemcomitans (Aa).

RESULTS

At baseline and T1, none of the suspected periodontal pathogens were detected at test or control sites. Levels of P. intermedia and F. nucleatum, as mean percentages of total culturable microflora, were detected at levels significantly higher in control sites than test sites at times T2 and T3.

CONCLUSIONS

Findings from this study suggest that e-PTFE membranes are frequently colonized by periodontal pathogens, and that bacterial colonization of healing sites after GTR procedures can be kept under control with a controlled delivery system releasing tetracycline.

Bacterial colonisation during GTR treatment. A longitudinal analysis

The purpose of the present study was to evaluate the long-term biological and clinical effects of a controlled delivery system releasing tetracyclines during the healing of interproximal periodontal defects treated by the technique of guided tissue regeneration (GTR) using e-PTFE membranes.

METHODS

Fifteen patients, each with two comparable interproximal periodontal defects, underwent surgical treatment with e-PTFE membranes in conjunction with tetracycline fibres at the test site and e-PTFE membranes alone at the control site. Microbiological specimens were taken from each site treated at baseline (T0) and one year after surgery (T4). Plaque index (PI), gingival index (GI), pocket depth at probing (PD) and attachment level at probing (PAL) were recorded at baseline (T0) and one year after surgery (T4). The presence of selected pathogenic microbial species, Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi), Fusobacterium Nucleatum (Fn) and Actinobaccillus Actinomicetemcomitans (Aa), was investigated and these species were identified by cultural methods.

RESULTS

No statistically significant difference in the level of periodontal pathogens was detected between the test and control sites at time T4. Likewise, no significant clinical difference between the test site and the control site was detected at time T4.

CONCLUSIONS

The results suggest that tetracycline fibres used in conjunction with e-PTFE membranes do not provide and further clinical and microbiological improvement or effect the healing of periodontal defects one year after GTR treatment.

Longitudinal study of dental implants in a periodontally compromised population

BACKGROUND

The purpose of this longitudinal study was to determine the clinical status and the composition of the subgingival microbiota of dental implants and natural teeth in patients with a history of periodontitis.

METHODS

Twenty-five partially edentulous patients treated for moderate to advanced adult periodontitis and having a total of 42 implants participated in this 3-year study. The assessment of clinical status was done 1, 2, and 3 years after prosthetic loading (T1, T2, and T3, respectively). Clinical parameters evaluated included probing depth (PD), clinical attachment level (CAL), gingival index (GI), and plaque index (PI). The subgingival microbiota at peri-implant and periodontal sites were analyzed at T1 and T2.

RESULTS

No significant difference in clinical parameters between implants and teeth and within the 2 groups between different time points was observed through the study. PD and CAL measurements of sampled periodontal and peri-implant sites did not show any statistically significant difference through the study and between the 2 groups. PI of sampled periodontal sites showed a statistically significant improvement during the study. From the morphological observation of the subgingival microbiota, a significant difference in the composition of motile rods between implants and teeth was found at T1. There were no differences detected in the subgingival microbiota, culturally identified at peri-implant and periodontal sites for the duration of the study.

CONCLUSIONS

In conclusion, implants were colonized by the indigenous periodontal microbiota and were well maintained in patients with a history of periodontitis. No significant association between progressing or non-progressing periodontal or peri-implant sampled sites in terms of loss of attachment and infection with at least one of the searched periodontal pathogens was found, suggesting that the presence of putative periodontopathogens at peri-implant and periodontal sites may not be associated with future attachment loss or implant failure.

A clinical comparison of the efficacy and efficiency of two professional prophylaxis procedures in orthodontic patients

This study compared the efficacy and efficiency of two professional prophylaxis procedures in orthodontic patients performing different oral hygiene regimens: the air powder polishing system (APP), and the rubber cup and pumice (RCP) technique. Sixty-two patients were divided into two groups: group I included 40 subjects who did not use any chlorhexidine mouthwash and group II comprised 22 subjects who regularly rinsed with a chlorhexidine mouthwash (at a 0.12 per cent concentration) and showed increased tooth staining. Using a split-mouth experimental design, the buccal and lingual tooth surfaces were cleaned in half of the mouth by the APP and in the opposite half by the RCP technique. Tooth surfaces were scored before (PRE) and after (POST) the experimental procedures for the plaque index (PI), and for the presence of tooth staining. In addition, the treatment time required by each procedure was recorded. In test group I, significant reductions in the PI after APP and RCP were observed. Likewise, in test group II, both procedures significantly reduced the baseline PI values. In both experimental groups, the percentage of stained sites significantly decreased after APP and RCP, but in test group II, APP seemed to be more effective than RCP. In addition, APP required significantly less time than RCP to remove dental plaque and staining. These data show that both professional prophylaxis procedures are effective in orthodontic patients, with APP being the most time-efficient technique and the most effective method for removal of tooth staining.

Exercise test in detecting anomalous behaviour of blood pressure in patients successfully operated on for coarctation of the aorta

Twenty-eight patients operated with success for isolated coarctation of the aorta (i.e. with normal blood pressure and upper/lower limb gradient < or = 20 mmHg at rest) underwent exercise testing to evaluate blood pressure and upper/lower limb pressure gradient during exercise. At maximum effort: 57% (16/28) of the patients were hypertensive and 43% (12/28) of patients increased upper/lower limb gradient over 35 mmHg. No significant correlation was found between the age at surgery (before or after 3 years of age) and maximal systolic blood pressure on exercise and maximal pressure gradient on exercise. The 12 patients with an exercise pressure gradient > 35 mmHg underwent digital angiography or magnetic resonance of the aorta. In 7 cases a mild residual narrowing was found (5 with mild transverse aortic arch hypoplasia, 2 with a mild residual coarctation). In 5 cases no residual narrowing was present. Many factors are thought to be involved in the anomalous behaviour of blood pressure during effort: in some cases anatomic factors, as residual narrowings of the aorta, in other cases functional factors, as increased forearm vascular reactivity, altered baroceptor function, different reactivity and structure of the pre- and post-stenotic aorta, etc., in other cases finally, both factors, anatomic and functional. We conclude that the exercise testing provides the best information on blood pressure modifications during activity and it allows to us to identify those patients which, because of exercise-induced hypertension, remain at risk of premature cardiovascular disease, also after a successful operation. However, when hypertension is found during effort, a strenous physical activity should be avoided and antihypertensive treatment may be required. So the cardiovascular risk due to hypertension can be reduced in the long term follow-up. Corrective surgery for coarctation of the aorta, introduced in 1944, has completely modified the natural history of the disease. Nowadays the operative risk is very low for isolated coarctation and the great majority of the patients is asymptomatic after surgical repair. Nevertheless, their life expectancy is substantially shortened, if compared with the survival curve of a normal population. The vascular and cardiovascular accidents, usually related to residual systemic hypertension, are the most common cause of this. Some studies in the literature have shown that many patients with normal blood pressure and no or little residual upper/lower limb pressure gradient at rest, may develop an anomalous blood pressure response e and/or a high upper/lower limb pressure gradient during exercise. We have studied by exercise test a group of patients successfully operated on for isolated coarctation of the aorta to evaluate the behaviour of the systolic blood pressure and the upper/lower limb pressure gradient during exercise. The aim was to recognize the patients who, inspite of very good operative result, remain at cardiovascular risk in the long-term follow-up.

Microbiotica associated with refractory periodontis. Prevalence and antibiotic susceptibility

BACKGROUND

The aim of the present study was to analyze the composition of subgingival microflora in patients with refractory periodontitis and to evaluate the antimicrobial sensitivity of isolated periodontopathic microorganisms to different antibiotics.

METHODS

Eleven subjects with a mean age of 46.4 years were selected for the present study. All had been treated for periodontal disease in the past. After further disease progression patients were included in this study. Eight subgingival plaque samples per patients were collected for cultural analysis.

RESULTS

"Black pigmenting anaerobic bacilli" were the pathogenic microorganisms more frequently isolated. The findings from antibiotic susceptibility test showed that high number of bacteria associated with refractory periodontitis resulted resistant to erythromycin, metronidazole and tetracycline. The most effective antibiotics were ciprofloxacin, amoxicillin-metronidazole and amoxicillin-clavulanic acid.

CONCLUSIONS

Microbiological analysis and antibiotic susceptibility test should be considered important tools in the management of patients with poor clinical response to conventional periodontal treatment.

[Transcatheter closing of patent ductus arteriosus using detachable coils]

Various devices have been developed for the percutaneous closure of persistent patent ductus arteriosus (PDA). In recent years Gianturco coils have become increasingly widespread for this purpose. Poor control during positioning is a major disadvantage of Gianturco coils, with resultant embolization of coils and residual shunts. Modifications to improve the positioning of coils have been developed. Very recently a new screwing detachable coil is available (Cook Cardiology, Europe). Between January 1996 and March 1999, 24 consecutive patients with PDA underwent cardiac catheterization. Twenty cases were judged suitable for this procedure, on the base of diameter and morphology of the ductus. Three cases were excluded because of the ductal diameter was too large (> 4.2 mm) and one because of its morphology (type B). In 19 patients a single coil was positioned, while in 1 case 2 coils were simultaneously used. In 19 cases (95%) complete closure was obtained (in 15 cases immediately, in 2 after 24 hours, in 2 after 1 month). One case showed a residual shunt and a second coil was applied eighteen months later with complete closure. So, considering also this last case, the closure was achieved in 100%. There were neither embolization or other complications. In conclusion, screwing detachable coil for PDA closure is a safe, very effective and at low cost technique. Therefore nowadays this procedure represents the method of choice for occlusion of small PDA (minimal diameter < or = 4 mm).

Combined effect of high-fat diet and copper deficiency during gestation on fetal copper status in the rat

We have previously shown that a low-copper (Cu) diet produced alterations in placental Cu transport and fetal Cu stores. Because Cu deficiency has been associated with lipid deposition in rat dam liver, we hypothesized that a high fat intake, a prevalent dietary habit in many populations, may worsen fetal Cu status and its closely linked iron (Fe) deposits. Pregnant rats were fed one of four diets during the second half of gestation: NFNCu: normal fat (7%), normal Cu (6 mg/kg); HFNCu: high fat (21%), normal Cu; NFLCu: normal fat, low Cu (0.6 mg/kg), and HFLCu: high fat, low Cu. One day before delivery, dams were anesthetized, and maternal as well as fetal plasma and tissues were obtained. Maternal, fetal, and placental weights were indistinguishable regardless of the group. Dam plasma Cu and placental Cu were lower in both LCu groups than in the NFNCu or the HFNCu groups. However, fetal plasma Cu was similar in all treatment groups. Dam and fetal liver Cu stores were reduced in the LCu groups compared to the NCu groups. This resulted in lower fetal/maternal liver Cu ratios in the NFLCu (1.79+/-0.14, p < 0.05) and HFLCu (1.59+/-0.21, p < 0.05) as compared to the NFNCu (4.12+/-0.44) and the HFNCu (4.15+/-0.27). Dam liver Fe was higher in the NFNCu than in HFNCu group (1.10+/-0.8 vs. 0.89+/-0.06 micromol/g, p < 0.05); fetal liver Fe from HFNCu and NFLCu dams was lower than that from NFNCu fetuses (NFNCu: 2.42+/-0.14; HFNCu: 1.92+/-0.15, p < 0.05; NFLCu: 1.81+/-0.10, p < 0.01). Fetuses of the HFLCu group had a lower heart Fe than the NFNCu group (0.56+/-0.03 vs. 44.0+/-3.0 microg/g, p < 0.01). These data indicate that a maternal high-fat diet can potentially aggravate the effects of Cu deficiency by further altering fetal Cu and Fe tissue stores.

Carotid rupture and intraplaque hemorrhage: immunophenotype and role of cells involved

BACKGROUND

A complete immunohistochemical characterization in complicated carotid plaques is still lacking. The cellular components of 165 carotid endarterectomy specimens were analyzed to assess their role in the pathogenesis of plaque rupture and intraplaque hemorrhage without rupture.

METHODS AND RESULTS

The fibrous caps at the sites of plaque rupture showed CD68+ macrophages, T-lymphocytes, and scarce B-lymphocytes. Ruptured plaques showed mononuclear infiltrates in the caps, shoulders, and bases of the plaques in 85% of the cases. Only 46% of nonruptured plaques showed such infiltrates (P <.0001). Two types of lipid cores were recognized: avascular or mildly vascularized and highly vascularized. The vessels of the latter type reacted with CD31 and CD34. In 57.5% of the cases, the base and the shoulders of the plaques showed neoformed, CD34+ vessels, often surrounded by mononuclear infiltrates. Intraplaque hemorrhage without rupture had highly vascularized lipid cores in all cases. T-lymphocytes and macrophages were in close contact with neoformed vessels.

CONCLUSIONS

Plaque rupture is characterized by mononuclear cell infiltration of the caps, whereas intraplaque hemorrhage without rupture is characterized by extensive vascularization of the plaque.

Effect of cyclosporin on apoptosis in human cultured monocytic THP-1 cells and synovial macrophages

OBJECTIVE

Cyclosporin A (CyA) is an immunosuppressant drug used for the treatment of rheumatoid arthritis (RA), that might affect programmed cell death (apoptosis) of the cells involved in the synovial inflammatory reaction. The effects of CyA on apoptosis were evaluated on cultured human monocytic myeloid cells (THP-1 cell line) and on RA synovial macrophages.

METHODS

In order to induce THP-1 cell differentiation into adherent cells, an amount of these was treated with human recombinant IFN-gamma before incubation with CyA. Primary cultures of synovial macrophages were obtained from RA patients and treated in vitro with CyA.

RESULTS

CyA, at the pharmacological range (100-300 ng/ml) employed in the treatment of RA, seems to induce, after 48-96 hrs, programmed cell death in differentiating THP-1 cells, whereas cultured synovial macrophages (fully differentiated monocytic cells) do not show any apoptosis at the same time.

CONCLUSION

Short-term CyA treatment may induce increased apoptosis in immature and differentiating cultured monocytes. Cultured synovial macrophages (resident monocytic-derived and differentiated cells) seem to be resistant to the treatment as far as apoptosis is concerned.

Placental copper transport in rats: effects of elevated dietary zinc on fetal copper, iron and metallothionein

We hypothesized that the competition between zinc (Zn) and copper (Cu) during fetal accretion of copper could be discriminated at either the dam-to-placenta or placenta-to-fetus stage. This premise was tested by feeding dams a high Zn diet (1000 mg/kg, HZn) during the second half of gestation. One day before delivery, dams were anesthetized, fetuses removed and both maternal and fetal tissues and plasma obtained and assayed. Other rats were fed a normal Zn concentration diet (32.4 mg/kg, ND) throughout pregnancy. There were significantly lower fetal liver Cu concentrations and greater plasma Fe concentrations, but not plasma Cu concentrations or liver Fe concentrations in the HZn group. Both dam and fetal Zn liver concentrations were greater in the HZn than in the ND group. Plasma Cu levels were lower in the HZn-fed than in the ND-fed dams. Placental tissue from the HZn litters had a greater concentration of Zn and Fe than did the ND group, whereas no effect was noted for Cu concentration. Metallothionein (MT) levels were elevated in dam livers and placenta in the HZn group, but there were no differences in fetal liver MT. The dynamic assessment of placental transport was conducted by injecting 2.5 mg/kg Cu acetate intravenously into dams of both groups. Sequential samplings of dam and fetal blood and placentas were taken from 0 to 60 min. After the Cu bolus, there was a consistently higher plasma Cu concentration in the HZn than in the ND dams, but no alteration in the concentration of Cu in the placenta or fetal plasma. This study indicates that placental Cu uptake is not affected by a high Zn diet in the dam. In addition, the greater Zn concentration in the placenta of HZn than in ND litters results in abnormal fetal Cu, Fe and Zn concentrations, suggesting that an imbalanced maternal mineral consumption is deleterious to normal divalent metal accretion.

Periodontal status and subgingival microbiota of insulin-dependent juvenile diabetics: a 3-year longitudinal study

This study examined for 3 years the changes in periodontal status and the possible correlations with selected subgingival microbiota and diabetic conditions in a group of 16 insulin-dependent diabetes mellitus (IDDM, JD) patients as compared with their 16 healthy cohabiting siblings (HS). JD patients were monitored every 3 months for levels of glycosylated hemoglobin (HbA1C). Clinical and microbiological parameters were measured 6 weeks before drawing blood to determine levels of HbA1C. Periodontal parameters were measured at baseline (TO), year 2 (T2), year 3 (T3) and included: probing depth (PD), attachment level (AL), sulcus bleeding index (SBI), and plaque index (PI). Two sites in each patient were selected for microbial samples: a mesio-facial aspect of the maxillary right first molar (defined as constant site, CS) and a site with the greatest probing depth (defined as deepest site, DS). Microbial samples were analyzed by culture techniques. No significant differences in clinical parameters were found between diabetics and healthy siblings at any examination. The SBI in the non-diabetic group at T2 and at T3 was significantly lower than at baseline. PD and AL of constant sites in the diabetic group at T3 were significantly higher than baseline. There was a significant increase in Prevotella intermedia at T3 as compared with baseline for deepest sites in the diabetic group. Cluster analysis revealed, in a former study, two clusters (IV and V) at baseline which were significantly different from the overall mean regarding composition of Porphyromonas gingivalis and Capnocytophaga spp. They were not significantly different for periodontal parameters from TO to T3. These data would suggest no significant differences in clinical parameters between the diabetics and non-diabetic siblings throughout this 3-year longitudinal study.

Placental copper transport in the rat. III: Interaction between copper and iron in maternal protein deficiency

Copper (Cu) and iron (Fe) metabolism are linked in the haematopoietic process. There is also considerable evidence of a linkage between protein intake and mineral sufficiency. The present study tested the hypothesis that a low protein diet during the second half of gestation in the rat alters Cu and Fe transport across the placenta and affects the Cu and Fe status of the fetus. Pregnant rats were fed a normal commercial diet the first half of gestation, and then assigned either a 20 per cent protein (NP) or a 4 per cent protein diet (LP) during the second half of gestation. One day before delivery, rats were anaesthetized, fetuses removed and dam tissues and plasma obtained. Other pregnant rats were injected i.v. with 2.5 mg/kg Cu acetate and sequential samples of dam blood, fetal blood and placentae were taken from 0 to 60 min. The LP diet produced generalized maternal hypoproteinaemia, and although there was no difference in fetal plasma albumin, there was a generalized fetal hypoproteinaemia as well. Fetal haematocrit (Hct) of the LP litters was lower than that of the NP group, but dam Hct was unchanged. Dam plasma Fe and Cu showed no differences between diets. Dam liver Cu was unaltered but liver Fe stores were elevated significantly. Before and after a Cu bolus, the LP placentae retained Cu to a greater extent than those of the NP placentae. Fetal liver Cu and Fe were elevated in the LP litters compared to the NP group. In conclusion, the LP diet in the dam during the second half of gestation was associated with fetal anaemia, hypoproteinaemia, and increased Cu and Fe accumulation in fetal liver. The higher concentration of Cu and Fe retained in LP placentae during gestation, and confirmed in the Cu challenge, suggest that Cu and Fe delivery to the fetus is related to placental concentration and that maternal protein malnutrition is a regulatory factor in fetal mineral homeostasis.

Endosperm balance number manipulation for direct in vivo germplasm introgression to potato from a sexually isolated relative (Solanum commersonii Dun.)

Diploid (2n = 2x = 24) Solanum species with endosperm balance number (EBN) = 1 are sexually isolated from diploid 2EBN species and both tetraploid (2n = 4x = 48, 4EBN) and haploid (2n = 2x = 24, 2EBN) S. tuberosum Group Tuberosum. To sexually overcome these crossing barriers in the diploid species S. commersonii (1EBN), the manipulation of the EBN was accomplished by scaling up and down ploidy levels. Triploid F1 hybrids between an in vitro-doubled clone of S. commersonii (2n = 4x = 48, 2EBN) and diploid 2EBN clones were successfully used in 3x x 4x crosses with S. tuberosum Group Tuberosum, resulting in pentaploid/near pentaploid BC1 progenies. This provided evidence of 2n (3x) egg formation in the triploid female parents. Two selected BC1 pentaploid hybrids were successfully backcrossed both as male and as female parents with S. tuberosum Group Tuberosum. The somatic chromosome number varied greatly among the resulting BC2 progenies, which included hyperaneuploids, but also a number (4.8%) of 48-chromosome plants. The introgression of S. commersonii genomes was confirmed by the presence of S. commersonii-specific randomly amplified polymorphic DNA markers in the BC2 population analyzed. The results clearly demonstrate the feasibility of germplasm introgression from sexually isolated diploid 1EBN species into the 4x (4EBN) gene pool of the cultivated potato using sexual hybridization. Based on the amount and type of genetic variation generated, cumbersomeness, general applicability, costs, and other factors, it would be interesting to compare the approach reported here with other in vitro or in vivo, direct or indirect, approaches previously reported.

Endovascular treatment of abdominal aortic aneurysms: lessons learned

The authors offer an overview of their 20-year involvement in the development of an endovascular graft for abdominal aortic aneurysm exclusion. Clinical experience gained throughout 6 years of clinical evaluation are reviewed, along with observations and insights on preoperative assessment, implantation techniques, and complications.

Testosterone metabolism and cyclosporin A treatment in rheumatoid arthritis

A constant dose-dependent side-effect in cyclosporin A (CSA)-treated patients is the appearance of hypertrichosis; this occurs in both sexes and suggests an androgenizing activity. To determine the influence of CSA on peripheral androgen metabolism, we evaluated in rheumatoid arthritis (RA) patients treated with low-dose CSA (3.5 mg/kg/day), during a period of 12 months, plasma levels of testosterone (Tes) and of 5alpha-androstane-3alpha, 17beta-diol glucuronide (Adiol-G), an important peripheral Tes metabolite. Clinical and laboratory parameters of RA were also monitored. Furthermore, the metabolism of physiological concentrations of Tes (1 x 10(-8) M) was evaluated in primary cultures of RA synovial macrophages (M phi) in the presence of CSA concentrations close to the pharmacological immunosuppressive doses (100-500 ng/ml). At the final time of observation (12 months), a significant increase in the mean plasma Adiol-G level was observed in patients of both sexes. The increase was evident after 1 month of treatment in male patients (P < 0.01) and after 3 months in female patients (P < 0.05). Almost all the patients experienced the side-effect of a low-degree hypertrichosis after a mean period of 1-2 months. No significant correlations with the laboratory parameters of the disease were observed. Results from in vitro experiments on Tes metabolism by cultured synovial M phi showed at 24 and 48 h, in the presence of CSA, a significantly (P < 0.0001) greater formation of dihydrotestosterone and increased amounts of other Tes metabolites, including androstenedione, androsterone and epiandrosterone, when compared to untreated controls. In conclusion, the appearance of a dose-related hypertrichosis and the increase in plasma androgen metabolites (i.e. Adiol-G) in CSA-treated patients, as well as the hormonal metabolic effects on cultured synovial M phi, should be regarded as possible markers of the influence of CSA on peripheral androgen metabolism at the level of target cells.

Craniomandibular disorders and orthodontic treatment need in children

Two hundred and forty subjects (113 boys and 127 girls), divided in three age groups, 7, 11, and 16 years were interviewed and clinically examined to estimate the prevalence of CMDs and the need for functional treatment, and to compare the functional status of the stomatognatic system in two subgroups: those judged to need orthodontic treatment and those judged not to need orthodontic treatment. Signs and symptoms of craniomandibular disorders were quite common and, in most cases, mild. There were significant differences in prevalence of CMDs between sexes. Only 3.7% of the patients were judged to need some functional treatment for CMDs. Trauma to the facial area and headaches were significantly associated with signs and symptoms of CMDs. No indication was found that oral parafunctions produce CMDs. No greater prevalence of CMDs signs and symptoms was found in subjects who needed orthodontic treatment than in subjects who did not need orthodontic treatment. In conclusion, preliminary results of this ongoing study support the contention that the high prevalence of signs and symptoms of CMDs is not really a measure of masticatory dysfunction, and that malocclusion does not appear to cause CMDs and/or to increase craniomandibular treatment need in a young population.

Carotid atherosclerosis. Immunocytochemical analysis of the vascular and cellular composition in endarterectomies

Papers dealing with rupture of carotid plaque surface are few in spite of the growing importance of the subject. The aim of this study was to analyze the cellular and vascular components of surgically excised carotid endarterectomies in order to obtain information about their role in the pathogenesis of the plaque rupture and intraplaque hemorrhage. Seventy-six surgical specimens of carotid endarterectomies were used for this study. The findings of immunophenotyping of the cellular constituents of the plaques were: 1) endothelial lining: the fibrous cap at the site of the rupture showed an eroded surface with loss of the endothelial lining. Conversely, in the remaining surface a continuous, not damaged row of endothelial cells stained with anti-CD31 and anti-CD34 was observed; 2) fibrous cap: the collagenous fibrous cap at the site of erosion was attenuated and the phenotypic characterization of the cells showed inflammatory components consisting mainly of macrophages (CD68 positive), 2/3 of the total infiltration. The remaining 1/3 was composed of T-lymphocytes and scarce B-lymphocytes. A close interaction between macrophages and capillaries and macrophages and T-lymphocytes was observed; 3) lipid cores: two different types of lipid cores could be depicted. Avascular or mildly vascularized lipid cores and highly vascularized, with neoformed vessels stained with CD34 and CD31. CD34 stained endothelia of all kind of vessels; conversely, neoformed vessels showed a weak stain with CD31. T-lymphocytes were found to be in close contact with neoformed vessels, and in some cases, migrating through the endothelial cells; 4) deeper layers of the plaque: the base and the shoulder of the plaques showed in 28/76 cases neoformed vessels, thin or thick walled, CD34 positive, generally surrounded by mild to extensive mononuclear infiltrates. Atherosclerotic plaques were found to belong to six different lesions: plaque rupture plus thrombosis (18/76, 23.6%), plaque rupture plus intraplaque hemorrhage plus thrombosis (18/76, 23.6%), intraplaque hemorrhage without plaque rupture (16/76, 21.0%), plaque rupture plus intraplaque hemorrhage (5/76, 6.5%), stable calcified non complicated plaque (14/76, 18.4%) and unstable, soft, non complicated plaque (5/76, 6.5%). The first four lesions were considered as "complicated lesions". Complicated plaques presented neoformed vessels in the periphery, shoulder and base of the plaque in 22/57 (38.5%) cases. Conversely only 1/14 (7.1%) of non complicated, stable calcified plaques presented neoformed vessels, (p < 0.05). Of note, the 5 causes of unstable, soft non complicated plaque presented neoformed vessels surrounding the plaque. In 10/57 (17.5%) complicated plaques unequivocal histological signs of old hemorrhages were found surrounding those vessels. Irrespective of presenting no rupture, 11/35 plaques showed a mononuclear infiltrate in the fibrous cap. In conclusion, rupture of carotid plaques (50% of the cases), is characterized by the presence of a macrophagic infiltration of the caps and by the direct apposition of T-lymphocytes to macrophages and a close relation of these cells to endothelial cells. This highly suggests a cell-to-cell interaction, which results in an inflammatory process. Intraplaque hemorrhage without rupture represented 21% of the endarterectomies. These lesions are not related to cap erosion, but to plaque vascularization. Most lipid cores were highly vascularized with neoformed vessels with macrophages and T-cells in close contact and in some cases disrupting the endothelium. The abrupt growing of the lipid core and/or an overproduction of oxygen free radicals could lead to the breakdown of core vessels and intraplaque hemorrhage.

Androgen and estrogen receptors are present in primary cultures of human synovial macrophages

Macrophages, as antigen-processing and -presenting cells to T lymphocytes, play a key role in the immune system and are suspected to be target cells of the sex hormone-related dimorphism in the immune response peculiar to rheumatoid arthritis (RA) pathology. In the present study, the use of specific monoclonal antibodies revealed immunostaining for androgen and estrogen receptors in primary cultures of macrophages obtained from synovial tissues of patients affected by RA and controls without RA disease. Soluble and nuclear type I (high affinity, low capacity) and type II (lower affinity, greater capacity) sites of androgen or estrogen binding were detected in primary cultures of RA macrophages using radioligand binding assay. Higher levels of type I and type II estrogen receptor compared to those of androgen receptor were found, particularly in the soluble fraction; however, contrary to what was observed in whole synovial tissues, higher steroid receptor concentrations were found in the soluble than in the nuclear fraction of RA synovial macrophages. Binding affinities and receptor contents of cultured synovial macrophages were comparable to those previously reported in other well established sex hormone-responsive cells and tissues. Further, specific messenger ribonucleic acids for sex hormone receptors, encoding for a sequence of the DNA-binding domain of the receptor proteins were revealed by RT-PCR.

Sex hormones, proto-oncogene expression and apoptosis: their effects on rheumatoid synovial tissue

Programmed cell death (apoptosis), is a non-random physiological process characterized by cell fragmentation without leakage of the cellular contents into the extracellular space. Apoptosis is especially important in the immune system. On the other hand the capacity of cells to proliferate and to show local invasiveness, as in cancer cells or the "tumor-like" synoviocytes in rheumatoid arthritis (RA), seems to be controlled by a group of genes called "proto-oncogenes". The early metabolic events in cell apoptosis and proliferation are remarkably similar. The primary location of apoptotic cells in RA synovial tissue is at the level of the synovial lining, varying from rare positive cells to > 50% positive cells. C-jun, c-fos and c-myc oncoproteins seem to be largely restricted to the synovial cells attached to the sites of cartilage and bone destruction. Ovarian follicle atresia could serve as a useful model to study the hormonal regulation of apoptosis in different endocrine tissues. Based on ovarian studies it seems that estrogens generally prevent apoptosis whereas androgens induce apoptosis. The binding of steroids to their receptors forms a complex wherein the receptors are transformed, so that they can then pass through the nuclear membrane and associate with specific recognition sites on DNA. In the majority of cases, the steroid receptors mediate the rapid regulation of the nuclear proto-oncogene transcription. Therefore, they may serve as important "early" regulatory genes and as excellent universal markers in all tissues in steroid hormone action. Since the macrophages are considered to be target cells for sex hormones, we recently evaluated c-myc expression in cytocentrifuge preparations obtained from primary cultures of RA synovial macrophages treated with estrogens, and observed a marked upregulation. Further studies of the influence of sex hormones on synoviocyte apoptosis and proto-oncogene expression should offer new perspectives on the pathogenesis and therapy of synovitis in RA and other rheumatic diseases.

Heterozygosity in 2n gametes of potato evaluated by RFLP markers

The heterozygosity transmitted through 2n gametes in potato was evaluated by following the segregation of RFLP markers in tetraploid progeny from bilateral sexual polyploidization in a cross between two diploid (2x) interspecific hybrids which produce 2n SDR eggs or 2n FDR pollen. Out of 84 probe/enzyme combinations tested, 23 revealed polymorphism between the parents and were heterozygous in at least one of the parents. These probes characterized 13 loci distributed on five different chromosomes of the potato RFLP map. The heterozygosity transmitted through SDR and FDR gametes was estimated to be 31.8% and 71.4%, respectively. Two different indices (LH and RHI) were used to select plants showing a high level of heterozygosity in the tetraploid progeny. The recombination events and the centromere positions were estimated for chromosomes I, VI and VII, following the segregation ratios of SDR or FDR gametes produced by the parents. A different recombination rate was observed between the two interspecific hybrids.

Periodontal status and selected cultivable anaerobic microflora of insulin-dependent juvenile diabetics

The periodontal status and subgingival microflora of insulin-dependent juvenile diabetic (JD) patients (n = 16, mean age = 11.3) were compared with that of their non-diabetic cohabiting healthy siblings (HS, n = 16, mean age = 13.2). JD patients were monitored every 3 months for levels of glycosylated hemoglobin (HbA1c) and clinical and microbial parameters were measured 6 weeks before drawing blood for levels of HbA1c (M% = 8.76). Clinical indices, measured for the entire permanent dentition, included: probing depth (PD), attachment level (AL), sulcus bleeding index (SBI), and plaque index (PI). Subgingival plaque samples were obtained at 2 sites from each subject; whenever possible, the site with the deepest probing depth and the mesial aspect of the maxillary right first molar were used. Microbial analyses were determined by cultural characteristics and biochemical tests. No significant differences were detected in any of the clinical indices for the entire dentition. The mean AL for JD sites was 2.32 +/- 0.83 mm and for HS sites was 2.2 +/- 0.85 mm. Mean percentage of total cultivable anaerobic microflora included Capnocytophaga spp. (JD, 13.21%; HS, 11%) and Porphyromonas gingivalis (JD, 5.1%; HS, 7.9%). Differences between the two groups were not statistically significant. When cluster analysis was performed on sampled sites, one cluster group in JD patients showed significantly elevated P. gingivalis and lower Capnocytophaga spp. levels as compared to the overall mean. The clinical parameters of this cluster were characterized by statistically significant greater loss of attachment and probing depth. These data would suggest few differences between JD patients and their HS in this population.

Macroamylasemia: a possible cause of unexplained hyperamylasemia in rheumatoid arthritis

Macroamylasemia is a benign acquired condition, characterized by a serum amylase unusually large in molecular size that has been found to occur in apparently healthy humans as well as in a variety of diseases including liver disease, diabetes, cancer malabsorption and autoimmune disorders. Most commonly macroamylasemia results from the formation of immune complexes between amylase and immunoglobulins. We describe the first case of an association between macroamylasemia/hyperamylasemia and rheumatoid arthritis characterized by the absence of immunoglobulins, as amylase binding globulins, within the macroamylase complex. Failure to identify macroamylase as the cause of unexplained but benign hyperamylasemia correctly, can lead to costly studies (e.g. ultrasonography, computerized tomography) to rule out pancreatic disease, and could induce prescription of unnecessary elemental diets and replacement therapies, as reported in our patient.

Antimicrobial susceptibility of periodontopathic bacteria associated with failing implants

The aim of this study was to examine the subgingival microflora associated with failing implants, and to determine their susceptibility to commonly used antibiotics in periodontal therapy and dental practice. Thirteen partially edentulous patients with 19 failing implants were selected. Clinical examination included probing depth, attachment level, gingival index, plaque index, and radiographic analyses. Two subgingival plaque samples were taken from each failing implant and analyzed for microbial composition. Fusobacterium nucleatum, Porphyromonas gingivalis, and Prevotella intermedia were the prevalent cultivable microflora. Antimicrobial susceptibility of isolates was determined by the agar dilution technique. Antibacterial activity of penicillin G, amoxicillin, amoxicillin-clavulanate, and the combination amoxicillin-metronidazole was significantly higher than with other antibiotics tested. These data indicated that the commonly-used antibiotics were highly effective against bacteria isolated around failing implants, which would suggest the use of these antibiotics to control peri-implant infections.

[Periodontal regeneration: the use of polypeptide growth factors]

Polypeptide growth factors are a class of potent natural biologic mediators which regulate many of the activities of wound healing including cell proliferation, migration and metabolism. Periodontal regeneration is thought to require the migration and proliferation of periodontal ligament cells on the root surface. In fact, repopulation of the detached root surface by cells from periodontal ligament (PDL) is a prerequisite for new attachment formation. Many studies suggested that Polypeptide Growth Factors (PGF) such as Insulin-like Growth Factor I (IGF-I), Platelet Derived Growth Factor (PDGF), Transforming Growth Factor B (TGF-B), Epidermal Growth Factor (EGF), are important mediators of cellular events in wound healing. Studies in vitro analysed the mitogenic effects determined on periodontal ligament cells by growth factors using (3H) Thymidine incorporation during DNA synthesis. The results suggested that recombinant human PDGF and IGF-I stimulate the proliferation of PDL fibroblastic cells and the combination of these growth factors showed a synergistic effect revealing the highest mitogenic effect among all individual growth factors as well as any combination of the growth factors tested. Furthermore these studies demonstrated that rh-PDGF and IGF-I stimulate chemotaxis of PDL fibroblastic cells, and supported a role for TGF-B as a regulator of the mitogenic response to PDGF in these cells. Other studies in vivo showed periodontal tissues regeneration introducing mixtures of recombinant human platelet derived growth factor and insulin-like growth factor into lesions of experimentally induced periodontitis in beagle dogs and monkeys.(ABSTRACT TRUNCATED AT 250 WORDS)

Cisplatin as a radiation sensitizer in the treatment of advanced head and neck cancers. Results of a phase II study

BACKGROUND

Surgery and radiotherapy mainstays in the management of advanced head and neck cancer, although historically, only 20-30% of patients survive. Therefore, in an attempt to improve locoregional control and survival, a multimodal protocol using cisplatin as a radiosensitizer was implemented.

METHODS

Between 1984 and 1990, 68 patients with advanced head and neck cancer (Stages III and IV) were treated with a regimen consisting of an induction phase of 4500 cGy and two cycles of cisplatin followed by an eradicative phase of either radical surgery (Group A, 27 patients) or radical radiotherapy (Group B, 41 patients). The maintenance phase chemotherapy consisted of adjuvant 5-fluorouracil (5-FU) and cisplatin after completion of locoregional treatment. Of the 68 patients, 19 had Stage III disease, and 49 had Stage IV; 21 had no regional lymph node metastases (N0), and 47 had regional lymph node metastases (N+).

RESULTS

The induction phase yielded a 26% (18 patients) complete response (CR) rate and a 57% (39 patients) partial response (PR) rate (response > 50%), yielding an overall response rate of 83%. Eleven patients (16%) had stable disease (ST) (i.e., < 50% response). The 2-year survival rates by initial treatment response for patients who had a CR, a PR, and stable disease were 53%, 56%, and 36%, respectively; for Groups A and B, 63% and 45%, respectively; for Stages III and IV, 68% and 43%, respectively; and for N0 and N+, 69% and 43%, respectively. In Group A, 14 of 27 patients (52%) had no viable tumor in the surgical specimen (i.e. had pathologic complete tumor clearance [CTC]); this subgroup had a 5-year survival rate of 58%. Ten patients (37%) who had gross total resection of tumor with negative margins but had tumor present in the specimen had a 5-year survival of 22%. In Group B, the 5-year survival rate was 43% for 27 patients who achieved CR after completion of radical radiotherapy (total tumor dose, 6480-7020 cGy). The 5-year survival rate of the 14 patients who had a PR and stable disease after radical radiotherapy and 3 patients whose resection was incomplete was 0%. The overall 2- and 5-year survival rates for all patients were 53% and 32%, respectively. Of 21 patients in whom treatment failed, most (90%) had a locoregional recurrence: 13 local recurrences (62%), 5 regional (24%), and 1 locoregional (5%). Two patients (10%) experienced failure at distant sites (the lung). Major treatment-related morbidity developed in two patients.

CONCLUSIONS

Although induction chemotherapy-radiotherapy produces a high clinical response rate, this does not translate into improved survival compared with historical controls. A subgroup that showed complete tumor clearance (CTC or pathologic complete response) at surgery had an apparent improved survival and merits further study. Patient selection did not appear to be a factor for the CTC group, because the majority of patients in this group had partial responses to induction therapy, nodal disease and advanced tumor stage, and tumor presence in unfavorable sites.

Stimulation of lamina propria lymphocytes by intestinal epithelial cells: evidence for recognition of nonclassical restriction elements

We have addressed the restriction elements involved in the interaction of lamina propria lymphocytes (LPL) and intestinal epithelial cells using the model of primary mixed cell culture reaction. Whereas peripheral blood T cells proliferate in response to both allogeneic non T cells and class II antigen-bearing intestinal epithelial cells (non T cells >> epithelial cells), LP T cells appear to proliferate preferentially in response to intestinal epithelial cells. The interaction between these cells does not appear to be restricted by conventional products of the major histocompatibility complex as neither monoclonal antibodies to class I nor to class II antigens inhibit the mixed cell cultures, whereas they are inhibitory in conventional mixed lymphocyte reactions. Furthermore, treatment of epithelial cells with interferon gamma fails to augment the cells' ability to induce proliferation of LPL while successfully enhancing proliferation of peripheral blood T cells in parallel cultures. Taken together, these data suggest that alternate restriction elements or mucosa-specific accessory molecules may exist on intestinal epithelial cells that are preferentially recognized by LPLs. Such a distinct regulatory network may be critical to the maintenance of immunologic homeostasis in the gut.

[The therapy of anterior disk dislocation in craniomandibular disorders. A clinical case report]

The authors discuss the outcomes of therapy for CMDs and present a clinical case reporting an alternative method for the treatment of disc displacement. The orthopaedic therapy for CMDs is based on the use of interocclusal splints. Two kind of splints are prescribed to patients with CMDs: stabilization or repositioning splint. The former is used for a conservative treatment, the latter for irreversible treatment. In view of the poor long-term success of repositioning therapy, the cost of subsequent dental treatment, and the great potential for iatrogenic occlusal and muscular problems, the authors believe that the initial treatment approaches should be, in any case, conservative, reversible, and non invasive. The authors prescribe to their patients the repositioning splint for use either part-time or full time use. Part-time use is effective for preventing disc displacement without reduction. If used full time, once joint noises, pain, and displacement are decreased, the appliance should be adjusted to/or replaced with a stabilization appliance to allow posterior positioning of the mandible into a more physiologically stable position. The authors present a clinical case, a 27 yo female with disc displacement with reduction was treated with stabilization splint. After 6 weeks of therapy she returned reporting a temporary closed lock and sharp pain in the left TMJ. An anterior repositioning splint was fabricated in order to position the mandible forward. After 10 weeks of this treatment the patient reported absence of joint/muscle symptoms and of joint noise.(ABSTRACT TRUNCATED AT 250 WORDS)

Macrophages, synovial tissue and rheumatoid arthritis

Macrophage-like synoviocytes originate in the bone marrow, like other mononuclear phagocytes, and are constantly replaced via the circulation. In rheumatoid synovium sections, 80-100% of the synovial lining cells are macrophage-like cells functioning as antigen processing- and antigen-presenting cells to T lymphocytes. Monocyte and lymphocyte traffic into the rheumatoid arthritis (RA) synovium is mediated by adhesion molecules such as endothelial-leukocyte adhesion molecule-1 (ELAM-1), vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecules-1 and -2 (ICAM-1 and ICAM-2), as well as monocyte chemotactic protein 1 (MCP-1) and beta 2 integrins (CD11 a,b,c/CD18). Macrophage-like cells in the RA synovium are highly activated based on their morphology, surface class II HLA antigen expression, and synthesis of cytokines such as interleukin-1 beta (IL-1 beta), tumor necrosis factor alpha (TNF-alpha), interleukin-6 (IL-6), granulocyte-macrophage colony-stimulating factor (GM-CSF), macrophage CSF, and transforming growth-factor beta (TGF-beta). Evidence for type 1 (higher affinity) and type 2 (lower affinity) androgen (ARs) and estrogen receptors (ERs) on macrophage-like synoviocytes in either male or female synovial samples from both RA patients and controls has been reported. In particular, ERs have also been found on CD8+CD29+ CD45R0+ T lymphocytes (memory), infiltrating rheumatoid synovial tissues. Sex hormones have been found to influence macrophage activity in experimental and clinical conditions such as RA. Generally estrogens have immunostimulatory effects, whereas androgens are immuno-suppressive.(ABSTRACT TRUNCATED AT 250 WORDS)

RFLP maps of potato and their alignment with the homoeologous tomato genome

An RFLP linkage map of the potato is presented which comprises 304 loci derived from 230 DNA probes and one morphological marker (tuber skin color). The self-incompatibility locus of potato was mapped to chromosome I, which is homoeologous to tomato chromosome I. By mapping chromosome-specific tomato RFLP markers in potato and, vice versa, potato markers in tomato, the different potato and tomato RFLP maps were aligned to each other and the similarity of the potato and tomato genome was confirmed. The numbers given to the 12 potato chromosomes are now in accordance with the established tomato nomenclature. Comparisons between potato RFLP maps derived from different genetic backgrounds revealed conservation of marker order but differences in chromosome and total map length. In particular, significant reduction of map length was observed in interspecific compared to intraspecific crosses. The distribution of regions with distorted segregation ratios in the genome was analyzed for four potato parents. The most prominent distortion of recombination was found to be caused by the self-incompatibility locus.

[Guided regeneration of the periodontal tissues with resorbable and nonresorbable membranes. II. Microbiological evaluation]

The present experimental study has been undertaken in order to analyze the influence of bacterial recolonization on periodontal wound healing following guided tissue regeneration therapy in humans. Two different surgical techniques has been carried out: one using a non absorbable membrane and the other a absorbable one. Microbiological data indicate no statistically significant difference between the techniques employed. Furthermore our data have confirmed the necessity of maintaining the healing sites free from the main periodontal pathogens.