Trends in Sustainable Dentistry.

ABSTRACT: The advance of Dentistry must take into account national, European and global policies for sustainable development and green transition. This article illustrates possible scenarios in this context for the next decade.

Syndrome of iron pill inhalation in four patients with accidental tablet aspiration: Severe airway complications are described.

Iron pill inhalation represents a uncommon cause of syntomatic endobronchial foreign bodies. Unlike foreign body, the direct contact of iron tablet onto the bronchial mucosa results in severe bronchial damage in addition to obstruction and local irritation. Four patients with Iron Pill Inhalation Syndrome are described. All but one patient developed irreversible bronchial stenosis as late post inflammatory complication. Bronchoscopic features and clinical evolution are described in order to reduce the risk of severe side-effects in patients highly suspected for iron pill aspiration.

Optimization by factorial analysis of caprylic acid precipitation of non-immunoglobulins from hyperimmune equine plasma for antivenom preparation.

Optimization of caprylic acid precipitation of equine plasma non-immunoglobulin proteins for antivenom preparation was achieved by regression analysis of the responses of three highly significant factors assayed by factorial design. The factors studied were caprylic acid concentration, plasma pH and temperature, and their response was assessed in terms of filtration speed, residual albumin, total protein content and turbidity. The results evidenced that the three variables are involved in the precipitation process. Moreover, the factors displayed significant interactions, indicating that their levels distinctly affect the optimization procedure. The best combination was 3% caprylic acid, 37 °C and plasma pH 4.9; under these conditions, all immunoglobulins and only 0.1% albumin remained in the supernatant, in a very fast and simple procedure. After formulation, the antivenom obtained by this procedure presented full lethality neutralizing activity and absence of protein aggregates.

Class of solvable nonlinear oscillators with isochronous orbits.

The nonlinear oscillator x¨+(2m+3)x(2m+1)x˙+x+x(4m+3)=0, with m a non-negative integer, is known to have a center in the origin, in a neighborhood of which are isochronous orbits, i.e., orbits with fixed period, not dependent on the amplitude. Here, we show that this oscillator can be explicitly integrated, and that its phase space can be completely characterized.

Analytic solutions to the shallow water equations.

Analytic, two-dimensional steady-state solutions to the rotating shallow water equations over variable topography are derived, by exploiting a drastic simplification of the equilibrium problem that occurs for nondivergent flows. For such flows, the equilibrium system decouples, and the cross-stream component of the momentum equation formally reduces to the barotropic vorticity equation. Thus, any solution to the barotropic vorticity equation can be used, in principle, to construct exact equilibrium solutions to the shallow water equations.

Immunochemical and morphometric features of astrocyte reactivity vs. plaque location in Alzheimer's disease

The quantitative relationship between glial fibrillary acidic protein (GFAP) hyper-reactivity and -amyloid protein (AP) deposition was investigated by double immunoperoxidase labeling of hippocampal and entorhinal cortex sections from five Alzheimer´s disease (AD) cases and five age-matched controls. AP plaques, which were absent in controls, were found in all AD samples, without significant differences in number or perimeter according to their location among the regions studied. In contrast, the mean number of GFAP (+) cells was significantly greater in the hippocampus than in the entorhinal cortex from AD cases (49 vs.39). Although at lower values (30 vs. 20), predominance of astrocyte hyperplasia in hippocampus as compared with entorhinal cortex was also found in control samples. Concomitant astrocyte hypertrophy, as defined by surface density (Sv) values of GFAP-immunoreactive material exceeding those of control means, affected a similar proportion of cells in the hippocampus (73%) and the entorhinal cortex (74%) from AD cases. Since an increased number of GFAP (+) cells in the hippocampus was not accompanied by an increased number and/or perimeter of neighbouring plaques, such differential hyper-reactivity in samples from AD patients, as well as in those with normal aging, seems to depend partially on the regional location of the involved astrocyte.

Health related quality of life in patients with Parkinson's disease two years following posteroventral pallidotomy.

BACKGROUND: There has been a new emphasis on the use of health related quality of life (HRQOL) measures for translating how a patient's response to treatment is experienced by the patient. The purpose of this study was to describe patient reported HRQOL two years after surgery in subjects who underwent posteroventral pallidotomy (PVP) for the treatment of Parkinson's disease (PD) and a subset of these same subjects four years following PVP. METHOD: A consecutive series of 52 subjects who were evaluated previously, prior to and at 4 months following PVP [3], received long term follow-up using mailed questionnaires. Twenty seven subjects (52% of the original sample) provided 2 year follow-up data and 15 of these subjects (29%) provided 4 year follow-up data. Severity of disease and subject reported HRQOL were evaluated. FINDINGS: Immediately following surgery, there was a sharp decrease in all measures of severity of disease. While there were differing patterns of increasing severity of disease among the measures following the immediate postoperative assessment, all of the measures remained better than the pre-surgery values. The data showed a pattern of marked improvement in HRQOL at 4 months following PVP. Over the 2 years following surgery, there was a gradual deterioration toward preoperative levels that nevertheless remained better than preoperative HRQOL. For the group with data at 4 years following surgery, there was no significant further deterioration in HRQOL between 2 and 4 years, with the 4 year data also remaining better than the preoperative HRQOL reports. CONCLUSIONS: In spite of advanced severe PD and advanced age, subjects in this study reported better HRQOL at 2 years following PVP than they reported at entry into the study prior to surgery. Additionally, the 15 patients who were available for follow-up at 4 years also reported better HRQOL than they experienced prior to the surgery.

Stretching, alignment, and shear in slowly varying velocity fields.

We derive criteria that locate intense material stretching and shear in two-dimensional flows with slow time dependence. Our derivation makes use of the near integrability of the equation of variations along trajectories of the slowly varying flow. The criteria yield two diagnostic scalar fields for use in real-time Lagrangian predictions in geophysical flows.

Long-lasting astrocyte reaction to persistent Junin virus infection of rat cortical neurons.

Immunoperoxidase labeling was performed in histological sections from rat brain harvested during acute (10-30 days), clinically inapparent (90-270 days) and late (450-540 days) stages of Junin virus-induced neurological disease. In frontoparietal cortex, count of viral antigen (+) neurons peaked during the acute period (27.7+/-6.8), dropped within the intermediate (4.8+/-4.0 to 1.4+/-1.1) and increased (7.6+/-4.3) at the onset of the late neurological syndrome. In infected vs. control rats, the number of GFAP (+) astrocytes maximized during the acute stage (19+/-4 vs. 11+/-5), and from the end of the intermediate (27+/-5 vs. 21+/-5) up to the late (37+/-7 vs. 26+/-6) periods. In turn, surface density of GFAP (+) material in infected samples peaked at 0.196+/-0.066, while it failed to exceed 0.090+/-0.043 in controls. Both astrocyte hypertrophy relapsing into chronicity, as depicted by surface density, and astrocyte hyperplasia preceding the onset of the late neurological syndrome, support their pathogenic contribution to disease expression.

Human serum antibodies against shared antigens of different stages of Trichinella spiralis: relevance of glycan and protein epitopes.

Taking into account that antibodies against the surface antigens of newborn larvae (anti-NBL Abs) present in sera from individuals with chronic trichinellosis recognize antigenic determinants of the excretory-secretory muscle larva products (ML-ESP), and that these products are mainly glycoproteins, the aim of this work was to assess the frequency of anti-NBL Abs in sera from individuals with acute and chronic trichinellosis, to analyse the relevance of glycan and protein epitopes of the ML-ESP in the cross-reactivity phenomenon, and its correlation with the host's serum response towards these products. Anti-NBL surface Abs were determined in sera by indirect immunofluorescence. The degree of recognition by serum and purified anti-NBL Abs was evaluated comparatively before and after chemical deglycosylation of ML-ESP by immunoelectrotransfer blot assay. Results showed that 64% of the sera from individuals with acute trichinellosis and 35% of those belonging to the chronic phase had anti-NBL Abs, and also that the protein epitopes are the major ones responsible for the cross-reactivity phenomenon involving the ML-ESP and the NBL surface during both phases of the infection, while glycan epitopes are immunodominant in the stimulation of the host's immune system. A modulatory phenomenon in the immune response generated towards Trichinella spiralis NBL driven by the ML-ESP is postulated.

Study of in vitro stability of liposomes and in vivo antibody response to antigen associated with liposomes containing GM1 after oral and subcutaneous immunization.

In order to evaluate the usefulness of liposomes as possible vaccine vehicles (oral and subcutaneous), the stability of liposomes in buffer, plasma and saliva at 25 and 37 degrees C was analyzed via fluorescence and enzymatic methodology. The tested mixtures included [EggPC/Chol] 1 : 1 (mixture I), [EggPC/Chol/SM] 1 : 1 : 1 (mixture II), [EggPC/Chol/SM/GM typeIII] 1 : 1 : 1 : 0.14 (mixture III), [EggPC/Chol/SM/GM1] 1 : 1 : 1 : 0.14 (mixture IV) and [DIAPC/DMPC] 1 : 1 non polymerized (mixture V) and polymerized (mixture VI); all mole ratio. Liposome mixtures I and II were more stable in buffer at 25 degrees C. On the other hand, mixtures III and IV were more stable in plasma at 37 degrees C; mixture VI was more stable in plasma at 37 degrees C than in buffer or saliva. Mixtures IV and V liposomes were both stable in saliva for at least one hour. Blood and feces anti-GM1 response to antigen associated liposomes after subcutaneous and oral administration was also examined. After mixture IV mice immunization, no detectable anti-ganglioside GM1 antibody response was detected. Negative stain transmission electron microscopy, shows that liposomes containing SM, GM1, GM typeIII and DIAPC : DMPC were twice the size of those made with EggPC/Chol. The hydrophobicity factor expressed as A(570/500) was obtained using the probe merocynine 540 (MC540). The order of fluidity increased from: mixture II < mixture I < mixture III < mixture IV < mixtureV < mixture VI. Although the high hydrophobicity factor for polymerizable lipids there are other factors like stability must be taken into account according to the administration via selected. Also, the hydrophilicity of the groups protruding from the membrane interphase into the solution in the case of subcutaneous inoculation is very relevant and for oral administration stability is the property to take into account, as long as they have to last through the different fluids of the gastrointestinal tract. The results obtained suggest that liposomes that showed stability in saliva and plasma at 37 degrees C containing GM1, GM typeIII or DIAPC/DMPC would serve effectively as a delivery vehicle for oral and subcutaneous non-viral vaccines.

Combined measurement of diabetes mellitus immunological markers: an assessment of its benefits in adult-onset patients.

The convenience of combining the measurement of antibodies to glutamic acid decarboxylase (GADA), protein tyrosine phosphatase (IA-2A), and autoantibodies to insulin (IAA) in diabetic patients was assessed. We analysed 71 type 1 and 115 adult-onset diabetic patients. The latter were grouped into three categories according to the time of evolution to insulin dependence. The main findings were as follows: (i) in type 1 diabetes, the combined analysis of GADA and IA-2A showed a sensitivity of 87.4% and was not appreciably improved by adding IAA; (ii) out of 31 adults who required insulin immediately or within the first two years of diagnosis, 41.9, 29.0, and 6.5% were positive for at least one, two or all three, and all three markers, respectively; GADA was the most prevalent (35.5%) and IA-2A the least represented (16.1%); (iii) 34 adult patients with slow evolution to insulin dependence showed a completely different profile: 5.9% were GADA positive and 23.5% were IAA positive and no double or triple positivity was observed as all patients were IA-2A negative; and (iv) 50 type 2 patients who had not required insulin treatment showed a low incidence of GADA (4%) as the only marker present. We conclude that a combined double-antigen test for GADA and IA-2A is a useful strategy for prospective screening of type 1 diabetes. However, in adults, the profile of individual markers discloses the course to insulin dependence. Therefore, it seems advisable to measure the markers separately, to allow a better classification of these patients, and help define their treatment.

Pericapillary arteriovenous malformations angiographically manifested as cerebral venous malformations.

Cerebral venous malformations have been diagnosed by angiographic features and are considered to be a benign anomaly. However, ample evidence indicates that stroke or similar symptomatology occurs in patients harboring a cerebral vascular malformation that was diagnosed angiographically as a venous malformation. The purpose of the study is to confirm the presence of a pericapillary arteriovenous malformation in these patients by analyzing the clinical history and surgical findings and correlating them with histological features. Thirteen patients were included in this study. Each patient fulfilled four criteria: 1. the patient was neurologically symptomatic; 2. the angiographic diagnosis was a venous malformation; 3. at operation, shunting arterioles (50-100 microns) were found to contribute to the malformation; and 4. histologically, a mixture of venous channels and arterioles with arterioles directly connected to venules was found. Based on the above findings, the malformation present in the 13 patients can be termed a 'pericapillary arteriovenous malformation'. Its angiographic distinction from the cerebral venous malformation requires technological advancement in the capability of magnifying images of arterioles and venules, along with improvement in image resolution.

Immunologic and genetic markers in insulin-dependent diabetes mellitus (type 1) in an Argentine population.

The objective was to evaluate the prevalence and association of several markers (islet cell antibodies: ICA, insulin autoantibodies: IAA, glutamic acid decarboxylase antibodies: GADA and ICA512 antibodies: ICA512A) along with HLA DQB1 genotype in type 1 diabetes mellitus of recent onset, including siblings and individuals without any history of this disease, in an Argentine population. A total of 79 children with type 1 diabetes mellitus of recent onset were studied, as well as 79 control children, and 68 healthy siblings of type 1 diabetic cases. IAA, ICA, GADA, ICA512A and HLA DQB1 alleles were determined. Sensitivity was 67.1% for ICA, 36.7% for IAA, 74.6% for GADA and 63.4% for ICA512A. None of the control subjects was positive for the immunological markers. Combined sensitivity of ICA-IAA-GADA was 89.8%, similar to the ICA512A-GADA (87.3%) or ICA512A-GADA-IAA combination (91.1%). GADA correlated positively with ICA, but no such correlation was found between IAA, ICA512A and ICA. IAA correlated negatively and GADA positively with age. IAA was associated to DQB1*0201, whereas ICA and ICA512A associated to DQB1*0302. Among siblings, 3/68 (4.4%) were positive for IAA and a single case (1.5%) was positive for GADA and one for ICA512A. Our findings show that the combination of multiple tests increases the sensitivity for prediction, with the ICA512A-GADA combination proving highly sensitive and equivalent to other proposed combinations, such as ICA-IAA-GADA.

Detection of GDNF secretion in glial cell culture and from transformed cell implants in the brains of live animals.

Current ex vivo gene therapy for Parkinson's disease using glial cell line-derived neurotrophic factor (GDNF) is limited by the lack of a monitoring mechanism to determine the expression of GDNF once the cells or other vehicles are transferred into animal models. The purpose of this study was to test whether a Renilla luciferase (RUC)-GDNF fusion protein secreted by the genetically engineered glial cell line RG-1 could be measured photometrically in cerebrospinal fluid (CSF). RG-1 was constructed by permanent transformation with a plasmid DNA construct that contains a GDNF cDNA (gdnf) fused to a RUC cDNA (ruc). The fusion protein secreted by RG-1 was shown to retain both GDNF and RUC activity. The concentration of GDNF determined by enzyme-linked immunoadsorbent assay (ELISA) was correlated with the light emission detected by assaying for RUC bioluminescence in RG-1 culture medium, indicating that RUC can be used as a reporter for GDNF in vitro. The cells were then implanted into rat brain (n=20), and the cisternal CSF was analyzed. Bioluminescence was successfully detected in the CSF samples, and was quantified over a period of 25 days, while Western blotting and ELISA failed to detect GDNF in CSF, presumably because the concentration of the RUC-GDNF fusion was too low. This study demonstrates that the transformed glial cell line RG-1 offers a sensitive self-reporting assay for GDNF expression.

A quantitative approach to correlate astrocyte differentiation and phagocytic activity.

A triple staining procedure (PAP labeling for GFAP, PAS reaction for added yeast cells and hematoxylin for nuclear staining of the whole cell monolayer) had disclosed that Junin virus infection enhanced phagocytic activity by inducing greater astrocyte differentiation. Here, we resorted to a mathematical approach for simultaneous evaluation of astrocyte differentiation and potential phagocytosis. At light microscopy level, the total number of: a) PAS-stained yeast cells, b) PAS-stained yeast cells associated to GFAP-positive astrocytes, c) GFAP-positive astrocytes, and d) total number of GFAP-labeled and non-labeled astrocytes, were counted within the monolayer area delimited by a grid with a total area of 0.01 mm2. As the percentage of PAS-stained yeast cells associated to GFAP-positive astrocytes correlated significantly with the percentage of GFAP-positive astrocytes for the three yeast cell incubation times (24, 48 and 72 h), a mathematical approach involving a so-called beta parameter representing the percentage of differentiated astrocytes capable of taking up 50% of added yeast cells, was developed. Since beta value dropped along yeast cell incubation time, and more markedly in Junin-virus infected samples, a numerical value was thus available to assess enhanced phagocytic activity in astrocytes undergoing differentiation. Therefore, the application of a mathematical approach to cell monolayers subjected to current staining techniques, allows more objective analysis of data provided by cursory visualization at light microscopy level.

Changes in health related quality of life in patients with Parkinson's disease with and without posteroventral pallidotomy.

Traditional clinical outcome measures for the treatment of Parkinson's disease (PD) have focused on motor function and activities of daily living. However, in the past decade there has been a new emphasis on the use of health related quality of life (HRQOL) measures for translating how a patient's response to treatment is experienced by the patient. The purpose of this study was to describe patient reported HRQOL in subjects who underwent Posteroventral pallidotomy (PVP) for the treatment of PD compared with a similar group of subjects who did not undergo surgery (non-PVP). A consecutive series of patients who underwent PVP (n = 52) was compared prospectively with a similar group of patients, who received adjustments to medications without surgery (n = 45). Severity of disease and self reported HRQOL were evaluated at two time periods. Time 1 data were collected within one week prior to surgery for the PVP group or when subjects received medication adjustments for the non-PVP group. Time 2 data were collected 4 months later. Results showed that the severity of disease improved from Time 1 to Time 2 for both groups. HRQOL improved significantly for the PVP group (p = 0.001) but not for the non-PVP group (p > 0.29). Changes in HRQOL were most strongly related to the improvement in severity of disease in the "off" state. The results of this study suggest that PVP is associated with significant improvements in clinical and patient reported outcomes four months following surgery compared with a similar group of patients who did not undergo surgery. Additionally, the results suggest that the difference in perceived outcome between the groups is due in part to the improvement in the levodopa "off" periods which occurred for the PVP group but not for the non-PVP group.

Correlation of intellectual impairment in Parkinson's disease with FDG PET scan.

This study investigated the relationship between regional glucose metabolism with intellectual impairment in patients with Parkinson's disease using statistical parametric mapping. Regional cerebral glucose metabolism using [18F]deoxyglucose (FDG) PET scans were performed on 10 patients with Parkinson's disease. We used the intellectual impairment score from the UPDRS. PET scans were analyzed with SPM96. Patients showed significant positive correlations with left limbic structures such as the cingulate gyrus, parahippocampal gyrus, and medial frontal gyrus. Patients showed significant negative correlations with associative neocortical posterior structures such as bilateral parietal and occipital gyrus. There were significant relationships between regional glucose metabolism and intellectual impairment.

Replacement of methionine-161 with threonine eliminates a major by-product of human glutamate decarboxylase 65-kDa variant expression in Escherichia coli.

Most insulin-dependent diabetes mellitus patients gen-erate conformational autoantibodies to the islet-cell 65-kDa variant of human glutamate decarboxylase (GAD65), and several immunochemical tests for the early detection of type-1 diabetes rely on GAD65 antibody (GADA) assessment using properly folded recombinant GAD65 as the antigen. In addition, preventive therapies based on tolerization by GAD65 administration may be available in the near future. Therefore, there exists a strong interest in a facile and economically sound expression procedure for this antigen. Several attempts to produce, in native form, wild-type GAD65 in Escherichia coli have failed. However, this difficulty was recently surmounted in our laboratory by expressing GAD65 as a fusion protein with thioredoxin [Papouchado, Valdez, Ghiringhelli, Poskus and Ermácora (1997) Eur. J. Biochem. 246, 350-359]. In this work, a new GAD65 hybrid gene was prepared by joining engineered cDNA obtained from human and rat tissues. The new gene was modified additionally to finally code for human GAD65 with a single amino-acid substitution: Met-161-->Thr. This change impeded the co-expression of a 48-kDa by-product from an internal translation site. Also, a second 58-kDa by-product was identified as a GAD65 C-terminal proteolytic fragment that co-purifies with thioredoxin-M161T GAD65. The new GAD65 variant was expressed and easily purified, yielding an antigen that performed equally or better than wild-type GAD65 in the reference radiobinding assay for GADA. The procedure provides an inexpensive source of large amounts of fully active and immunochemically competent GAD65.

Serotonergic decompensation in the akinetic expression of Parkinson's disease.

The current diagnostic and treatment paradigm for the akinetic form of Parkinson's disease asserts that the majority of symptoms and treatment phenomena arise from a dysfunctional dopaminergic system. Recent studies have attempted to determine the roles of other biogenic amine neurotransmitters such as serotonin and norepinephrine. Metabolic breakdown product studies of Parkinsonian and non-Parkinsonian cerebrospinal fluid (CSF) samples indicate significant differences in the levels of serotonin and norepinephrine in addition to the levels of dopamine. Such changes may suggest that current pharmacologic therapies that attempt to restore only dopamine are inadequate, and require accompanying therapies to elevate serotonin and norepinephrine levels.