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PubMed2001

Laboratory evaluations of a toothbrush with diamond-shaped filaments for stiffness and efficacy.

The purpose of these studies was to evaluate four toothbrushes with a similar flat profile for stiffness and efficacy in removing artificial plaque deposits from interproximal areas, or depth of removal from broad tooth surfaces, and to relate these findings to bristle stiffness. The test toothbrush had 5-mil diameter, elongated diamond-shaped bristles (D). Three toothbrushes contained 5-mil (5), 6-mil (6), or 7-mil (7) diameter round bristles. Stiffness studies were performed using the ISO 8627 method. In the efficacy studies, toothbrushing was conducted with a vertical or horizontal brushing motion on simulated anterior or posterior teeth using a brushing weight of 250 g. The bristles were placed at a 90 degrees angle to the tooth surface, and brushing was performed for 15 seconds at two strokes per second with 50 mm strokes. Each of the toothbrush designs was tested 24 times. Interproximal access efficacy (IAE) was recorded as the maximum width of simulated plaque deposit removed. Depth of deposit removal (DDR) was determined using a color comparative scale, where 0 = no deposit change and 4 = maximum removal. The averages of wet and dry stiffness measurements were found to be 7 > D > 6 > 5; all values were in the range accepted as soft texture. The means for total IAE were ranked D > 5 > 6 > 7, and total DDR mean rankings were D > 7 > 6 > 5. For the round bristles, stiffness was inversely related to IAE and paralleled the DDR rankings. Using ANOVA, the D and 5-mil toothbrushes had significantly higher (p < 0.05) IAE means compared to the 6- or 7-mil products. The D toothbrush had significantly higher (p < 0.05) DDR means than the 5-mil product. The diamond-shaped bristles in these flat profile products resulted in improved depth of deposit removal compared to the same design with 5-mil round bristles.

Dental Plaque↗
PubMed1992

[Blackfan-Diamond disease and malignancy: cause effect relationships?].

The authors report on a 24-year old patient with Blackfan-Diamond syndrome who developed a Hodgkin's disease. This patient became transfusion-dependent at the age of 10, after an initial period of corticosensitivity, and after failure of androgens. He developed hemochromatosis despite from parenteral chelation therapy. He died of infectious complications 4 months after the diagnosis of Hodgkin's lymphoma. A review of the literature shows an increased incidence of malignancies in Blackfan-Diamond syndrome (three cases of leukemia), and in similar disease (thalassemia and sickle cell disease), but not in other patients with hemosiderosis (primitive hemochromatosis, end-stage renal failure under dialysis). Etiopathogenic hypotheses are discussed.

Adult↗
PubMed1992

Fourier transform infrared analyses of some particulate drug mixtures using a diamond anvil cell with a beam condenser and an infrared microscope.

Although the diamond anvil cell (DAC) has been used in many forensic science laboratories for the analysis of trace evidence, few applications of this technique for the analysis of controlled substances have been reported. This may be due to both an unfamiliarity on the part of forensic drug chemists with this accessory and the nature and quality of spectra that result from use of a DAC on a dispersive instrument. Along with low energy throughput, which results in relatively high noise levels, strong broad diamond absorptions occur. With the use of a Fourier transform infrared instrument, these do not present a problem and nanogram quantities of materials can be analyzed when the DAC is used with an infrared microscope. Since single crystals can be sampled with the DAC, simple physical separations (involving particle-picking) can be used in certain cases to isolate drugs from particulate mixtures for infrared analysis. This method is especially useful for some "difficult" mixtures and residues, and several examples of such analyses involving samples of forensic science interest are presented.

Amobarbital↗
PubMed1992

Rotary Diamond Chart--a new visual field screening device.

The Rotary Diamond Chart (RDC) is presented as a new clinical method suitable for screening general optometry patients for visual field defects. A pilot study was conducted using both the rotary diamond chart and a central 76-point threshold-related screening test (Allergan-Humphrey) on 21 consecutive clinical patients. Full-threshold field testing was then completed on those subjects failing either screening test. The RDC detected five of six visual field defects including one very subtle defect which was not detected by the automated screening test. The sensitivity of the RDC visual field screening assessment was 83.33 percent with a specificity of 100 percent. These results suggest that the RDC is an effective clinical visual field screening test. It is easy for the clinician to use and for the patient to understand.

Adult↗
PubMed1992

The death penalty and Bernard Diamond's approach to forensic psychiatry.

Bernard Diamond would testify only for the defense in criminal cases, but only if the whole psychiatric truth would be introduced during a trial and the facts of the case supported the defense position. Otherwise, he would refuse to participate. Although few other forensic psychiatrists have personal or professional ethical concerns regarding ever participating for the prosecution, many more have such problems in capital cases. Bernard Diamond's approach to forensic psychiatry should be considered at least as an option by those opposed to the death penalty. Bias in capital cases is not a persuasive reason to withdraw from involvement if the forensic psychiatrist remains honest.

Capital Punishment↗
PubMed2005

[H(alpha) line and the optimum experimental condition for diamond deposition in EACVD].

The process of atomic hydrogen emission in the CH4/H2 gas mixture in EACVD was simulated by Monte Carlo method. In the simulation the collision between electron and H2 molecule has two basic types: elastic collision and inelastic collision. Four types of inelastic processes have been considered, namely vibrational excitation, dissociation, electron excitations and ionization. For e-CH4 collision, elastic momentum transfer, vibrational excitation, dissociation, ionization, and dissociation ionization were considered. The relationship between the numbers of H, and CH3, and the atomic hydrogen emission line intensity under different experimental conditions was investigated. A method of extrapolating the optimum experimental condition for diamond deposition by the atomic hydrogen emission line is given. The result is of great importance to depositing high quality diamond films by controlling the conditions of technology efficiently.

English Abstract↗
PubMed1975

Gardner-Diamond syndrome with multiple glomus tumors.

The case of a patient with two unusual dermatologic entities, multiple glomus tumors and the painful purpura of Gardner-Diamond syndrome, is reported. The diagnosis of multiple glomus tumors was confirmed by biopsy, and the Gardner-Diamond syndrome was confirmed by reproduction of the painful purpura with the intradermal injection of the patient's sonicated erythrocytes.

Adult↗
PubMed2006

[Spectroscopic ellipsometry investigations of amorphous diamond films deposited with filtered arc].

In order to investigate thoroughly the optical properties of amorphous diamond (alpha-D) films deposited by the filtered vacuum arc technology, the optical constants of the films were measured by spectroscopic ellipsometry. Moreover, the dispersion relations of the optical constants, and the correlations among refractive index, extinction coefficient, optical gap and the substrate bias were also analyzed. It has been shown that the refractive index of alpha-D films is higher than that of diamond crystal, and the absorption edge corresponding to the interband transformation can be described with the parabolic line shape. With increasing the wavelength, the extinction coefficient gradually declines and approaches nearly to zero in the infrared band. In addition, the adjustable amplitudes of the optical constants owing to the changing bias also reduce strikingly with the extension of the wavelength. With raising the bias, the refractive index and the optical gap firstly augment, then minish, and there is a maximal value when the substrate bias is -80 V. However, the extinction coefficient firstly minishes, then augments, and there is a minimal value when the bias is -80 V.

English Abstract↗
PubMed1991

Familial insulin-dependent diabetes mellitus (IDDM) epidemiology: standardization of data for the DIAMOND Project. The WHO Multinational Project for Childhood Diabetes Group.

The WHO Multinational Project for Childhood Diabetes, known as the DIAMOND Project, has been responsible for establishing insulin-dependent diabetes mellitus (IDDM) registries and for carrying out diabetes incidence studies, descriptive epidemiological research, and analytical investigations which are being used to test specific hypotheses regarding the etiology of the disease. Standardized epidemiological data are being collected from countries around the world, permitting international comparisons between registries. Multinational studies are also beginning to investigate the potential genetic determinants of the disease, and are contributing to the development of familial IDDM epidemiology worldwide. The development of standards for data collection of IDDM family histories is important for multinational studies of IDDM recurrence risks in families, descriptive analyses of patterns of familial aggregation, and comparative analytical investigations of specific etiological determinants of IDDM in relatives. These activities are being implemented through the DIAMOND Project.

Child↗
PubMed1989

Diamond-Blackfan anemia: promotion of marrow erythropoiesis in vitro by recombinant interleukin-3.

To clarify the defective erythropoiesis in eight patients with Diamond-Blackfan anemia, we studied their bone marrow response in vitro to recombinant human interleukin-3 (IL-3) and recombinant granulocyte-macrophage colony-stimulating factor (GM-CSF). In an erythropoietin-containing assay system, specimens from six of the eight patients yielded low numbers of erythroid colonies compared to control values, and in five of these no erythropoietin dose-response could be elicited. Addition of IL-3, GM-CSF or both to cultures from the six patients had no effect on CFU-E-derived colonies. In contrast, IL-3 but not GM-CSF induced a marked increase in the number (183%) and size of the BFU-E-derived colonies in five of the six cases and partially corrected the impaired dose-response to erythropoietin in four. Bone marrow from the other two patients yielded numbers of CFU-E and BFU-E colonies comparable to controls and manifested similar increments in colonies with increasing concentrations of erythropoietin. When IL-3 was added to these cultures, further increments were observed in the number and size of BFU-E colonies. We conclude that IL-3 enhanced the marrow erythropoiesis in most of the patients and exerted a corrective effect on the aberrant colony formation in the presence of erythropoietin. The data raise the possibility of IL-3 as a therapeutic agent in Diamond-Blackfan anemia.

Adolescent↗
PubMed1988

[Scanning microscopy comparison of keratotomies using a diamond or steel knife].

We have compared on 4 cadaver eyes the aspect of keratotomies obtained with a diamond blade or a steel blade. We used the scanning electron microscope for the comparison. The incisions with diamond blade are much thinner than the incisions with steel blade. However the steel blade produced regular and smooth keratotomies. Whatever the blades, the microscopic appearance of the penetration was much better than the exit. The choice between cutting instruments for keratotomy depends upon these results and financial factors.

Humans↗
PubMed1978

Decreased serum complement in the Gardner-Diamond syndrome: immunofluorescent findings and association with angioimmunoblastic lymphadenopathy.

Immunologic and immunofluorescent profiles of two patients with the Gardner-Diamond syndrome are described. During the time ecchymoses were present, both patients had decreased serum complement levels; when the lesions healed, the serum complement level returned to normal. One patient had associated angioimmunoblastic lymphadenopathy and subepidermal deposits of immunoglobulin IgM at the basement membrane of ecchymotic skin. The other patient had a normal immunofluorescent pattern. Both patients had increased B-cell counts. The association of immunologic and immunofluorescent findings in patients with the Gardner-Diamond syndrome is suggestive and deserves further study.

Adult↗
PubMed1986

[Studies on the pathogenesis of congenital hypoplastic anemia (Diamond-Blackfan syndrome)].

CFU-E growth from fractionated bone marrow cells of five patients with Diamond Blackfan syndrome was studied. In all patients, CFU-E growth was reduced in mononuclear cell rich fraction. In two patients out of five, CFU-E growth was returned to normal by the depletion of E-rosette forming cells of monocytes from mononuclear cell rich fraction. In the patient whose CFU-E growth returned to normal by the depletion of E-rosette forming cells, cocultivation between bone marrow buffy coat cells and autologous bone marrow E-rosette forming cells resulted in a significant decrease of CFU-E growth, and there was a significant increase in CFU-E growth by the treatment of OKT 4. In other three patients out of five, there was no significant increase in CFU-E growth by the depletion of monocytes and/or E-rosette forming cells. It is concluded that immunologic causes such as cellular factors may play a role, at least in part, on the pathogenesis of Diamond-Blackfan syndrome.

Anemia, Aplastic↗
PubMedDate not supplied

[Ecchymotic patches of the fingers and Gardner-Diamond vascular purpura].

Ecchymotic patches on the fingers and vascular purpura in Gardner-Diamond syndrome are two benign but recurrent clinical disorders occurring chiefly in young women. They involve superficial cutaneous hemorrhagic signs. Both disorders testify to microvascular fragility without perturbation of general hemostasis. Diagnosis is easy for those familiar with the disorders. Ecchymotic episodes accompanied by sharp pain begin at the roots of the fingers. Microtraumatism is soon seen to be involved. Ecchymosis develops at the flexor muscles of the fingers but "capillary" resistance is only reduced in one third of cases. The pathogenic explanation involves rupture of a small post-capillary vein due to disorders in the control system of kinins and local metabolites. The autoerythrocyte sensitization syndrome described in 1955 by Gardner and Diamond is characterized by painful and febrile episodes followed by purpuric and ecchymotic lesions of the skin on various parts of the body, but not necessarily on the legs. Dysneurotonic effects are frequent but diagnosis is based upon promotion of the disorder by intradermal or subcutaneous injection of a minimal quantity of autologous blood. Immunological effects are considered but the ailment involves microvascular control disorders, notably of the capillary-vein segment, in particular at Copley's endo-endothelial fibrin film. Imbalance in fibrin formation and lysis is associated with perturbation of the kinin and serotonin systems. In addition to the use of certain bioflavonoids and calcium inhibitors, prevention and treatment should involve consideration of drugs which affect plasticity in the vascular wall and pericapillary interstitial conjunctiva and the rheological properties of blood flow and interstitial tissue.

Ecchymosis↗
PubMed1986

Progressive hyperopia in radial keratotomy. Long-term follow-up of diamond-knife and metal-blade series.

In an earlier report, the authors demonstrated a trend toward progressive hyperopia in radial keratotomy (RK) patients examined between one and three to four years postoperatively. In those 109 cases, the surgeries were performed using a metal-blade instrument. In the following study, the metal-blade series was updated to a total of 225 procedures, and a more recent series of 300 procedures performed on 228 patients was examined in which a diamond-knife cutting instrument was used. Patients had uncorrected visual acuity determination, cycloplegic refractions with best corrected visual acuity measurements and keratometry measurements. The authors demonstrated a hyperopic shift in the distribution of postoperative spherical equivalent (SE) values across time such that higher proportions of cases in both metal-blade and diamond-knife series were at least 1.0 diopter (D) away from emmetropia at 24 and 48 months than was the case at 12 months after surgery. Regression analysis determined that none of the preoperative or surgical variables known to affect refractive outcome of RK (alone or in combination) could account for the changes in refraction seen during the course of postoperative time. In general, changes in keratometry paralleled refractive changes, but were somewhat smaller in magnitude.

Cornea↗
PubMed1987

Combined asthma and alveolitis induced by cobalt in a diamond polisher.

A diamond polisher presented with a history of dyspnea, chest tightness, chills and weight loss related to exposure to diamond cobalt disks at work. Pulmonary function showed slightly reduced lung volumes, low normal diffusing capacity and a moderate bronchial hyperresponsiveness to histamine. Chest X-ray and cell count in bronchoalveolar lavage fluid were normal. After 3 months of non-exposure, a bronchial cobalt challenge test caused an immediate decrease in specific airway conductance and in vital capacity (VC) but not in FEV1/VC. After 6 h, chills, fever, tachycardia and crackles appeared along with moderate reductions in lung volumes. After 24 h, the bronchoalveolar lavage fluid showed 43% granulocytes, and there was a marked increase in bronchial hyperresponsiveness to histamine. These changes are interpreted as combined asthma and alveolitis induced by cobalt.

Alveolitis, Extrinsic Allergic↗
PubMed1985

[Borderline structure and painful skin hemorrhages: a case of Gardner-Diamond syndrome].

The Gardner-Diamond Syndrome is an infrequently diagnosed impressive psychosomatosis. The patients (exclusively female) suffering from this disorder are described as "angry young women". They are considered hysterical, masochistic, depressive, hostile and timid. Physically the syndrome is characterized by atypical, painful, apparently spontaneous skin bleeding in young women and these patients look like they have been beaten, injured or are seriously ill. Besides hematoma, renal hemorrhage, uterine hemorrhage, headaches or unconsciousness as well as numerous symptoms of conversion in the narrower sense of the word have been observed, e.g. loss speech, gait deviation, or feelings of discomfort. To this day the pathophysiological peculiarity that enables the patients to transform subconscious psychic events into the specific temporary alteration in the permeability of the capillary walls being a constitutional variant characteristic of females suffering from Gardner-Diamond Syndrome and activated by psychic stimuli. In the case history presented, the problem is the psychic working out of narcissistic injuries in the context of a borderline structure. These injuries turn into physical symptoms analogous to the process of conversion. Since, in this case, there is no question of a defense against oedipal fantasies one would prefer to speak of a "narcissistic conversion". Quite peculiar is the universally described resemblance of the patients to one another. The syndrome, together with the character and psychodynamic features, is repeated in almost a stereotypical manner. An explanation for this phenomenon cannot be expected even from the discovery of a pathophysiological detail in the blood vessels. Rather, we are confronted with one of those extremely rare syndromes where, in a limited field, physical and psychic events are completely blended. The physical events such as affects and defense mechanisms for which they can be substituted at random and without mutual interference. It is as though these disorders had retained a phylogenetically lost unity and primeval capability of interchanging psychic and somatic structures and, so to speak, preserved them in the manner of a museum. These syndromes make us surmise that in processes of somatization a recourse to ancient, long-faded psychosomatic relationships may play a certain role.

Adult↗