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Summary Background Systemic sclerosis (SSc) is characterized by target-organ fibrosis and microvascular dysfunction, which can be assessed using nailfold capillaroscopy. Dermoscopy is a useful and easily performed method for diagnosing skin lesions. Aim To compare conventional capillaroscopy, using the gold-standard method (conventional stereomicroscope nailfold capillaroscopy; SNFC), with polarized light noncontact dermoscopy (PNCD) and nonpolarized light contact dermoscopy (NPCD), and to evaluate their accuracy in diagnosing characteristic SSc-related alterations. Methods The study enrolled 45 patients with SSc. Capillaroscopy images and photographs were taken with three devices, SNFC, NPCD and PNCD, and these images were randomly analysed by a blinded observer. Results The scleroderma pattern was found in 83% of patients. PNCD and NPCD were highly sensitive in identifying the presence of focal capillary loss (96.4% and 100%, respectively), haemorrhage (96.2% and 92%, respectively), and scleroderma (91.9%, 94.6%), and showed high specificity for haemorrhage and enlarged loops. The intra-observer kappa values for detection of the scleroderma pattern by SNFC images, NPCD and PNCD were moderate to good: (κ = 0.71 (95% CI 0.44–0.95), κ = 0.60 (95% CI 0.35–0.83) and κ = 0.60 (95% CI 0.32–0.86), respectively. Evaluation of haemorrhage presence gave high kappa values for all methods: κ = 0.77 (95% CI 0.57–0.95), κ = 0.90 (95% CI 0.76–1.00) and κ = 0.95 (95% CI 0.85–1.00), respectively. Conclusions Both polarized and nonpolarized dermoscopy are reliable methods for valuation of nailfold capillaroscopy in patients with SSc. They are easy to perform, with good rates of accuracy and results that are comparable with traditional capillaroscopy.

Several germline mutations and sequence variants in cancer predisposition genes have been described. Among these, the CDKN2A p.A148T variant appears to be frequent in patients with melanoma, at least in certain ethnic groups. In this case-control study, we evaluated 127 patients with cutaneous melanoma and 128 controls from Southern Brazil, the region with the highest melanoma incidence rates in the country. Using PCR-RFLP, we demonstrate that CDKN2A p.A148T variant was significantly more frequent in patients with melanoma than in controls (12.6% vs 3.9%; P=0.009). There was no association between presence of the polymorphism and tumor thickness, site of the primary tumor, melanoma subtype, age at diagnosis, quantitative and qualitative number of nevi. Patients with a positive family of history for other cancers were particularly prone to carry the CDKN2A p.A148T allele. All patients with p.A148T-positive melanoma reported European ancestry, especially German, and this was confirmed using a panel of ancestry-informative INDELs. Our data suggest that CDKN2A p.A148T is a melanoma susceptibility allele in Southern Brazil and is particularly common in patients with melanoma of predominantly European ancestry.

BackgroundStudies suggest a paucity of and lack of prioritisation in mental health research from low- and middle-income (LAMI) countries.AimsTo investigate research priorities in mental health among researchers and other stakeholders in LAMI countries.MethodWe used a two-stage design that included identification, through literature searches and snowball technique, of researchers and stakeholders in 114 countries of Africa, Asia, Latin America and the Caribbean; and a mail survey on priorities in research.ResultsThe study identified broad agreement between researchers and stakeholders and across regions regarding research priorities. Epidemiology (burden and risk factors), health systems and social science ranked highest for type of research. Depression/anxiety, substance use disorders and psychoses; and children and adolescents, women, and people exposed to violence/trauma were prioritised among the disorders and population groups respectively. Important criteria for prioritising research were burden of disease, social justice, and availability of funds. Stakeholder groups differed in the importance they gave to the personal interest of researchers as a criterion for prioritising research. Researchers' and stakeholders' priorities were consistent with burden of disease estimates, however suicide was underprioritised compared with its burden. Researchers' and stakeholders' priorities were also largely congruent with the researchers' projects.ConclusionsThe results of this first ever conducted survey of researchers and stakeholders regarding research priorities in mental health suggest that it should be possible to develop consensus at regional and international levels regarding the research agenda that is necessary to support health system objectives in LAMI countries.

Here we present an overview of the experimental evidence and of the conceptual basis for the involvement of lamins and nuclear envelope proteins in a group of genetic diseases collectively referred to as laminopathies. Some of these diseases affect a specific tissue (skeletal and/or cardiac muscles, subcutaneous fat, peripheral nerves), while others affect a variety of tissues; this suggests that the pathogenic mechanism of laminopathies could reside in the alteration of basic mechanisms affecting gene expression. On the other hand, a common feature of cells from laminopathic patients is represented by nuclear shape alterations and heterochromatin rearrangements. The definition of the role of lamins in the fine regulation of heterochromatin organization may help understanding not only the pathogenic mechanism of laminopathies but also the molecular basis of cell differentiation and ageng.

The existence of a nuclear polyphosphoinositol metabolism independent from that at the plasma membrane is now widely recognized. Specific changes in the nuclear phosphatidylinositol (Ptdlns) metabolism have been implicated in cell growth, differentiation, and neoplastic transformation. Here we shall review the main features of nuclear inositol lipid signaling through type I IGF receptor, focusing the attention on the role of inositide-specific phospholipase C (PI-PLC) beta1 in cell proliferation and differentiation, given its peculiar localization in the nuclear compartment.

We compare the prevalence of obsessive-compulsive symptoms in schizophrenic patients in treatment with clozapine and those who receive classic antipsychotic drugs.Outpatients with schizophrenia treated with clozapine (n = 56) or classic antipsychotic drugs (n = 54) at the Honorio Delgado-Hideyo Noguchi Specialized Institute in Mental Health (Lima-Peru), were evaluated for the presence of obsessive-compulsive symptoms by means of the Obsessive-Compulsive Disorder Module of Structured Clinical Interview for DSM-IV and Yale-Brown Obsessive-Compulsive Symptoms Checklist.46.4 % of patients treated with clozapine presented obsessive-compulsive symptoms while this occurred in 20.4 % of those with classic antipsychotic drugs (p = 0.005). In addition, 21.4 % of patients with clozapine and 13 % of those treated with classic antipsychotics presented obsessive-compulsive disorder according to DSM-IV criteria (p = 0.31).In schizophrenic patients, treatment with clozapine is associated with a higher rate of obsessive-compulsive symptoms than treatment with classic antipsychotic drugs.

To assess sexual risk behavior for human immunodeficiency virus (HIV) infection and other sexually transmitted diseases (STD) in males with psychotic disorders and to compare it to that of the patients without these disorders.We used a structured interview to collect information regarding sexual risk behavior, knowledge about HIV/AIDS, history of STD and drug use. We included 106 patients with psychotic disorders from a psychiatric institution and 89 control medical out-patients from a general hospital.Among psychotic patients, 70.8% declared that they had had sexual intercourse at some time in their lives and 37.7% during the last year. The psychotic patients had significantly less knowledge about HIV/AIDS than the controls and they had a smaller proportion of stable sexual partners and greater frequency of sexual risk behaviors, such as inconsistent condom use and sexual intercourse with prostitutes. In psychotic patients, inconsistent condom use was associated with more hospitalizations.Although patients with psychotic disorders have reduced sexual activity, they present greater frequency of sexual risk behaviors that predispose them to acquire HIV infection and other STD.

The objective of this study is to validate a version in Spanish of the Edinburgh Postnatal Depression Scale (EPDS) in Peruvian women with less than 1 year of delivery.We administered the EPDS and the SCID section for diagnosis of major depression according to DSM-IV criteria to 321 women within the first year of postpartum.We found that the optimum cut-off score of the EPDS for the studied population was 13.5. With this value the sensitivity was 84.21% and the specificity 79.47% for diagnosis of major depression. No woman with score lower than 7.5 had major depression (sensitivity and negative predictive value were 100%). The correlation coefficient between the EPDS score and the number of criterion A symptoms for major depression according to DSM-IV was 0.4478. The Cronbach's alpha coefficient was 0.7043. The items that had more predictive power for postpartum depression were those regarding worries, ability to cope, panic, cry and optimism.The version in Spanish of the EPDS performed adequately in Peruvian women.

Dentin proteoglycans are fundamental constituents of the dentin matrix and are distributed ubiquitously both in dentin and cement. They have several important functional properties; in particular, they have a fundamental role in the maintenance and the correct stabilization of collagen fibers. The use of phosphoric acid on dentin, as proposed in most common dental adhesive systems to establish a reliable bond, may affect the molecular structure of proteoglycans. The aim of this study was to evaluate, after the application of EDTA or phosphoric acid on dentin, the dentin proteoglycans with an immunocytochemical approach with high resolution SEM. For this purpose, dentin disks obtained from recently extracted human molars were etched with a 35% water solution of phosphoric acid for 15 s, 30 s, and 60 s. Control specimens were conditioned with EDTA. Specimens were immunolabeled with a monoclonal antibody antichondroitin sulfate and visualized with a gold-conjugated secondary antibody. Conditioning dentin with EDTA resulted in a distinct labeling of the proteoglycans, as visualized on branching fibrillar structures in the order of 10-20 nm. The use of 35% phosphoric acid on dentin revealed a coagulation of proteoglycans after etching for 15 s while a very low labeling signal was detectable after 30 s. No labeling was obtained after etching dentin with phosphoric acid for 60 s. These results suggest that the use of 35% phosphoric acid on dentin is able to produce significant structural modifications of the dentin proteoglycans even after short application times. Additionally, when applied on the dentin surface for more than 30 s, phosphoric acid produces a dramatic decrease in proteoglycans' antigenicity, probably due to structural modifications of the three-dimensional conformation of these molecules.

The objective of this study is to validate a version in Spanish of the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS).We administered to 20 patients with obsessive-compulsive disorder (OCD) the Maudsley Obsessive-Compulsive Inventory (MOI) and a version in Spanish of the Y-BOCS. The application of the last one was performed by an interviewer, filmed, and then watched and rated by other 4 observers. In addition, the opinion of the treating psychiatrist about the severity of the patient's symptoms was registered. The interviewer and the observers were named raters.The mean scores of the Y-BOCS assigned by the 4 observers were from 18.35 to 19.55; the maximum scores, from 34 to 35; and the minimum scores, from 1 to 5. The Pearson's correlations between raters were significant for all cases (r0.86 and p0.001). For all raters, Y-BOCS scores significantly correlated with MOI scores (p0.001) and the opinion of the treating psychiatrist (p0.05). We did not find significant correlation between the last one and MOI scores. The Cronbach's coefficients ranged from 0.8789 to 0.9488.The Spanish version of the Y-BOCS is reliable, homogeneous and valid for quantification of the obsessive-compulsive symptoms, and has more correlation with the opinion of the treating psychiatrist than the MOI.

Although common in clinical settings, major depressive disorder with associated anxious symptoms ('anxious depression') has not been well studied in antidepressant clinical trials. The aim of this study was to compare the effects of fluoxetine versus amitriptyline in this group of patients. After a single-blind placebo run-in period of 2 weeks, patients were treated on a double-blind basis with fluoxetine or amitriptyline for 8 weeks. Assessment instruments included: 21-item Hamilton Rating Scale for Depression, Hamilton Rating Scale for Anxiety, Clinical Global Impressions, Raskin Depression Scale and Covi Anxiety Scale. A total of 157 patients were randomized to either fluoxetine or amitriptyline. Fluoxetine was given at a fixed dose of 20 mg/day and amitriptyline was given in a range of 50-250 mg/day (mean of 138.1 mg/day). Fluoxetine was comparable to amitriptyline in all efficacy measures except the HAMD sleep factor. Unwanted effects were more frequent and more severe in the amitriptyline-treated patients. Fluoxetine was comparably efficacious to amitriptyline in the treatment of major depression with associated anxiety. Since fluoxetine was far better tolerated, it is a promising alternative for this frequent and disabling condition.

The objectives of the research are to determine the prevalence of major depression after childbirth and compare it with that of non-postpartum women; and to study the risk factors for postpartum depression.We studied 425 women: 321 women in the first postpartum year, 41 nulliparous women and 63 women with more than 1 year postpartum.The prevalence of major depression in the first postpartum year was 5.92%; this value was significantly lower than that of the women with more than 1 year postpartum. In women with less than 2 years postpartum we found less depression than in those with more than 2 years of delivery. The risk factors associated with postpartum depression found by logistic regression were: obsessive-compulsive disorder, premenstrual dysphoric disorder, previous major depression, maternity blues, young age and lower educational grade.Our study does not support the existence of a greater prevalence of major depression during postpartum in Peruvian women.

The new generation of field emission in lens scanning electron microscopy with the sample located within the objective lens allows the observation of uncoated biological samples. Here we describe HeLa metaphase chromosomes isolated by two procedures and the localization within these chromosomes of a DNA centromeric probe. Chromosomes isolated in methanol acetic acid show 10 nm fibers organized in a three dimensional network while the structure of chromosomes obtained by the polyamine method's characterized by very dense short protusions of 30-50 nm in thickness. In situ hybridization with a DNA centromeric probe revealed by colloidal gold particles demonstrate that the hybridization occurs at the level of the 10 nm fiber with a high definition in the localization of specific DNA sequences.

Tumor irradiation induces modifications in the interaction of surviving target cells with immune cells. This interaction is mediated by adhesion molecules, whose expression can be strongly altered by radiation treatment. Here the probably of K562 tumor cells for lymphocyte binding was studied after exposure of target cells to different doses of gamma-radiation. Results were correlated to the expression of ICAM-1 and LFA-3 adhesion molecules on target cells. Radiation treatment enhanced the expression of both ICAM-1 and LFA-3 on the surface of target cells in a dose and time of culture-dependent fashion, reaching a maximum 24 hrs postirradiation, when also lymphocyte binding was increased. 10-30 Gy irradiation of K562 cells in vitro induces after 24 hrs, an up-regulation of ICAM-1 and LFA-3 expression that, in turn, increase lymphocyte binding, making tumor cells more exposed to cytotoxic attack. The progressive morphological damage induced by radiation, documented by the scattering singlas in flow cytometry and by electron microscopy analysis of irradiated K562 cells, induced, particularly at delayed times of culture in high doses irradiated cells, alterations of the target cell surface that might prevent the correct interaction with immune cells.

In order to detect proliferative processes in human marginal gingiva in pathological conditions and after externalization of titanium implants, we have attempted BrdU incorporation after "in vitro" incubation of tissue fragments. In comparison with healthy controls, immunocytochemical detection of samples from patients affected by hypertrophic gengivitis shows a good number of proliferating cells in the basal layer of the epithelium, while only in one case can positiveness be detected after externalization of titanium implants. Since after reduction of inflammation by hygienic treatment a low number of proliferating cells can be observed only in the regions where pathological alterations are also present, we suggest that the increase in tissue proliferation may be closely dependent on the intensity of the inflammatory process. All these data demonstrate that in vitro BrdU incubation of tissue fragments represents a suitable method to evaluate cell proliferation in human tissue.

The recognition of effector cell populations that are able to actively from conjugates with target cells is of major importance in studies of lymphocyte cytotoxicity. A number of methodologies have been described to identify the conjugates and count them, but there have been few studies of the binding capability of the different subsets of effector cells involved in the conjugation phenomenon. Here we describe a methodology that permits the study of two surface markers on lymphocytes conjugated to K562 target cells. In particular, the expression of low density CD8 (CD8dim) has been studied on both CD3+ and CD16+ lymphocytes bound to K562 target cells. Previously described methodologies, either optical microscopy or flow cytometry, were not able to identify the effector population by mAb double staining, especially in the case of antigens expressed at low density. The flow cytometric methodology described here permits the measurement of the binding activity of small lymphocyte subsets such as the CD3+ 8dim+ population. However, the method could be used to study the binding activity of any effector population defined by mAb double staining.

Antacids are often the first therapeutic approach in patients with pyrosis. We carried-out a study on 8 healthy volunteers who underwent a 24 hour gastric pH-metry to assess the real efficacy of magnesium hydroxide administration on gastric acidity. Magnesium hydroxide was alternatively administered at different dosages (400 mg or 800 mg) in the population studied. Our results showed a mild and non reproducible response to lower dose, but, on the contrary, the 800 mg dose always induced an immediate, effective and prolonged antacid action, reaching a maximum pH value of 5 and lasting up to 40 minutes. Our study confirms, using a modern and reliable technique as the 24-hour gastric pH-metry, the antacid activity of magnesium hydroxide.

In the present paper some general and technical features of two of the commonest pH and manometric long-term ambulatory recording devices available in Italy are reviewed.

The sensitivity of human natural killer (NK) cell activities (both binding and killing) after exposure of peripheral blood mononuclear cells to different doses of gamma radiation was studied. A panel of monoclonal antibodies was used to identify the NK and T-lymphocyte subsets and to evaluate their radiosensitivity. Peripheral blood mononuclear cells were irradiated with low (2-6 Gy) and high (10-30 Gy) doses and NK cell binding and cytotoxic activity against K562 target cells were studied after 3 h and 48 h in culture. The primary damage to NK cell activity was identified at the postbinding level and affected mainly the lytic machinery. After 48 h culture postirradiation, an overall depression of cytotoxic activity was observed, but ionizing radiation produced either a selection of the more cytotoxic NK cell subsets, which therefore might be considered more resistant to radiation damage than the less cytotoxic NK cells, or a long-term stimulation of cytotoxic activity in surviving cells.

Nuclear matrices, purified from normal and chronic lymphocytic leukemia lymphocytes, exhibit a close association with the centriole. This finding suggests that the nuclear and cytoplasmic skeletal systems are linked by transmembrane connections represented by nuclear matrix constituents. This could account for the observed synchrony between transformations of the centriole and particular nuclear events which take place during the cell cycle and suggests that the nuclear matrix, besides being involved in DNA replication and chromosome condensation, should affect the centriole cycle which controls the cytoskeleton organization.

We report the cytogenetic data of two patients with erythroleukemia showing the chromosome Ph'. In one case the chromosome Ph', as revealed with the GTG band technique was the result of a translocation involving the chromosomes 19 and 22. The aim of this work is to provide more contribution to the knowledge of the origin of the Ph' and to give data in the field of this disease for which few cytogenetic data are available after the introduction of the banding techniques.

A reagent is described for the colorimetric enzymic determination of high-density-lipoprotein (HDL) cholesterol. The reagent can be used with HDL fractions isolated by the various methods of precipitation of low- and very-low-density lipoproteins we investigated. The considerable sensitivity obtained by use of Barham-Trinder's reaction allows the sample/reagent volume ratio to be decreased to 1:80, and major interferences thus eliminated. The response is linear from 100 to 2000 mg of HDL cholesterol per liter. The maximum CV obtained in precision tests was approximately 1% within series and approximately 3% between series. Most of the bilirubin interference is eliminated by adopting a reaction pH of 6.1. Because of its sensitivity, the reagent is particularly suitable for use with HDL fractions isolated after precipitation with polyethylene glycol 6000, which are characterized by a marked dilution. HDL cholesterol determination with the proposed reagent is accurate and precise. Values obtained are in line with those provided for by the Abell-Kendall method. The method can easily be automated.

The effect of tiropramide hydrochloride--a new spasmolytic drug with calmodulin-independent activity--in correcting alterations of intestinal transit, has been investigated in 40 IBS patients (20 with accelerated and 20 with delayed transit time). Intestinal transit has been evaluated by means of radioopaque markers. Tiropramide hydrochloride, at a dose of 100 mg t.i.d. for 4 weeks, was found significantly more effective than placebo both in normalizing intestinal transit time and in inducing symptomatic relief.

We report cytogenetic data concerning 9 patients with chronica granulocytic leukemia and eosinophilia at the onset and during the chronic phase of the disease before the blastic crisis. The cariotype analises in the intermediate phases allowed to determine the first changes which could be involved in the evolutionary events of the disease up to the moment in which the typical markers of the blastic crisis can be found.

The effects of pinaverium bromide, a non-absorbable antispasmodic agent, administered locally, on sigmoid-rectal motility was investigated in 20 patients with irritable bowel syndrome. The influence of either pinaverium (10 subjects) or placebo (10 subjects) on a neostigmine-induced increase of sigmoid pressure was assessed and compared by means of computerized electromanometry. The drug was found to counteract significantly the motor effects of neostigmine, thus appearing to be an effective compound for the treatment of functional disorders of the colon.

Radionuclide impurities can significantly increase the absorbed dose in Nuclear Medicine examinations. The aim of this study is to evaluate the dose of Tl-200 and Tl-202 in patients injected with Tl-201 for myocardial scintigraphy. All relevant nuclear and biological data are reported; Thallium distribution in the body is then discussed with particular regard to the gastro-intestinal tract. Since MIRD Committee has not published "S" values for Tl-200 and Tl-202, these have been calculated by a computer code and are reported. The absorbed dose for these Thallium isotopes is presented. For example, kidney doses in Gy/GBq are 0.29 (Tl-200), 0.27 (Tl-201) and 0.97 (Tl-202). The total dose increase for a 2% presence of Tl-202 is about 11%.

Passaretti S, Mazzotti G, de Franchis R, Cipolla M, Testoni PA, Tittobello A. Esophageal motility in cirrhotics with and without esophageal varices. Scand J Gastroenterol 1989, 24, 334–338Esophageal manometry was performed in 45 cirrhotics with varices, in 15 cirrhotics without varices, and in 20 normal subjects, to define the effect of varices on esophageal motility. Cirrhotics with varices showed a decreased amplitude of motor waves in the lower half of the esophagus (p < 0.01), an increased duration of primary peristaltic waves along the entire length of the esophagus (upper esophagus, p < 0.05; lower esophagus, p < 0.01), and an increased peak-to-peak speed of primary peristaltic waves p < 0.01). Resting lower esophageal sphincter pressure and duration of sphincter relaxation were similar in patients and controls. The above-mentioned abnormalities might be due to the mechanical effect of the presence of varices.

Wharton's jelly (WJ) is an important source of mesenchymal stem cells (MSCs) both in human and other animals. The aim of this study was to compare human and equine WJMSCs. Human and equine WJMSCs were isolated and cultured using the same protocols and culture media. Cells were characterized by analysing morphology, growth rate, migration and adhesion capability, immunophenotype, differentiation potential and ultrastructure. Results showed that human and equine WJMSCs have similar ultrastructural details connected with intense synthetic and metabolic activity, but differ in growth, migration, adhesion capability and differentiation potential. In fact, at the scratch assay and transwell migration assay, the migration ability of human WJMSCs was higher (P

In this study, we analyzed the chromatin ultrastructure in interphase cells after different chemical fixations. In light of the fact that there is little information regarding the fixa- tion of biological samples in combination with molecular biology methods (such as DNA extraction and in situ hybridization methods) we analyzed the ultrastructure of chromatin in interphase cells fixed with different fixatives and tested under the same conditions for both DNA extraction and in situ hybridization. The results showed that, among the different combinations and concentrations we analyzed, the solution of 4% paraformaldehyde/0.1% glutaraldehyde was the best compromise in order to achieve a well-preserved morphology, successful DNA extraction, and specific signaling of in situ hybridization, suggesting a low interference of this fixative with the chromatin organiza- tion. Microsc. Res. Tech. 70:599-606, 2007. V C 2007 Wiley-Liss, Inc.

Guaiazulene (GA) is widely used as a natural ingredient in many health care products and solutions. Although it has been reported to have interesting biological effects, GA and azulene derivatives have been proven to be cytotoxic against normal human cells and human tumor cells; moreover, guaiazulene has shown photomutagenic properties on bacterial strains. Therefore, we evaluated and compared the cytotoxicity of GA at different concentrations on human gingival fibroblast (HGF) cell cultures under normal conditions and under UV irradiation (UV-A dose: 6.4 J/cm2). The compound tested was found to significantly reduce cell viability (dose-dependent trend, IC50 72.1 microM), decrease protein procollagen alfa1 type I synthesis, a marker for HGF protein, and COL1A1 mRNA expression. The cytotoxic effects were accompanied by activation of an intrinsic apoptotic pathway, studied using transmission electron microscopy (TEM) and caspase-3 activation. The light exposure of the cell culture treated decreased GA-induced cell death (IC50 128.9 microM), suggesting a photoprotective effect due to the photodegradation of the toxic agent, guaiazulene. Furthermore, the products of the photodegradation reaction of GA proved not to be toxic against HGFs.

The role and function of dentin matrix metalloproteinases (MMPs) are not well-understood, but they may play a key role in dentinal caries and the degradation of resin-bonded dentin matrices. To test the null hypothesis that MMP-9 is not found in dentin matrix, we used gelatin zymography to extract and isolate all molecular forms of gelatinolytic MMPs in demineralized mature sound dentin powder obtained from extracted human molars, characterizing and identifying the enzymes by Western blotting. Gelatinolytic MMPs were detected in extracts of demineralized dentin matrix and identified as MMP-2 and MMP-9. Acidic extracts (pH 2.3) yielded 3–8 times more MMP activity than did EDTA (pH 7.4). Their activation may contribute to dentin matrix degradation, which occurs during caries progression and following resin bonding. Inhibition of MMP-2 and -9 proteolytic activity may slow caries progression and increase the durability of resin-dentin bonds.

The use of electric current during the application of etch-and-rinse adhesive systems has been recently claimed to increase bonding of etch-and-rinse adhesives by enhancing substrate impregnation. The null hypothesis tested in this study was that electrically assisted application has no effect on bond strength of self-etching bonding systems. Three self-etch adhesives (Protect-Bond, Xeno III, and Prompt L-Pop) were applied with the aid of an electric signal-generating device (ElectroBond) and tested vs. controls prepared with the same disposable sponges but without electric current. Specimens bonded under the influence of electric current exhibited increased microtensile bond strength compared with the controls (p < 0.05). High-resolution SEM analysis showed that bonding under the influence of electricity reduced interfacial nanoleakage. It is speculated that resin infiltration may be improved by the attraction of polar monomers by an electric current or by modification of the dentin surface charges, resulting in better water substitution or evaporation.

The purpose of this study was to analyze the inner structure of chromosomes in cells arrested, fixed and cryosectioned in metaphase. The chromosomes in metaphase maps prepared using standard cytogenetic protocols, are usually covered by cellular debris, which obscures the structural details on the surface and limits analysis by techniques when using nanometric resolution. By using cryosectioning, the debris is removed and it is possible to analyze the internal structure of the chromosomes. We described the ultrastructure of chromosome sections fixed with either acetic acid, methanol or glutaraldehyde, evaluating the effect and the influence of the fixative on the morphology. Furthermore, we subjected those cells previously fixed with glutaraldehyde to osmic maceration in order to better visualize the intracellular structure. All samples were examined with a Field Emission In Lens Scanning Electron Microscope (FEISEM), which allows high-resolution analysis of biological samples without any metal coating. The results showed a package morphology in samples fixed with glutaraldehyde, mainly due to the high capacity of the fixative to strongly crosslink the proteins. In contrast, the fibrillar structure seen in cryosections fixed with acetic acid/methanol is due to the propensity of the fixatives to extract and remove proteins. We propose that in situ chromosomes fixed with glutaraldehyde and then osmicated are a good model for studying the inner structure of chromosomes by using high resolution scanning electron microscopy.