Time-dependent dissolution of amalgams into saline solution

The dissolution of mercury, silver, and copper from polished and unpolished surfaces of low- and high-copper amalgams into saline was investigated with respect to time via atomic absorption spectrophotometry. Greater amounts of mercury and silver were released from unpolished than from polished surfaces. Ion release was greatest during the first three hours after trituration of all amalgams. The rate of dissolution of ions from amalgams into saline is considered to be very low once the amalgam has set, and is probably inhibited by the formation of a surface film formed during immersion.

Osteoporosis, falls, and age in fracture of the proximal femur

The relative importance of osteoporosis and risk of falling in causing hip fracture is not known. Femoral neck bone mass was measured in 708 elderly people, all of whom had fallen and injured a hip. Below 75 years of age there was a steep increase in relative risk of fracture with reduced bone mass, measured by Singh grade. Above that age the increase in risk was small, and neuromuscular responses which protect the skeleton against trauma may be more important than bone mass.

Striated intramural gallbladder lucencies on US studies: predictors of acute cholecystitis

Ultrasound scans of 51 consecutive patients with gallbladder wall thickening were reviewed, and specific sonographic features were correlated with surgical and clinical follow-up. Two patterns of thickening were identified as specific indicators of the presence or absence of acute cholecystitis. "Striated" wall thickening, consisting of several alternating, irregular, discontinuous, lucent and echogenic bands, was seen in eight of 13 patients (62%) with acute cholecystitis. This pattern was not encountered in any of the patients who did not have acute cholecystitis. Conversely, "three-layer" thickening, consisting of a single circumferential lucent zone between two relatively uniform echogenic layers, was seen in only one of 13 patients (8%) with acute cholecystitis but in 11 of 38 patients (29%) with other diagnoses. Other abnormalities, including the presence of intramural echogenic foci and wall irregularities, were more frequently seen in patients with acute cholecystitis but were not as helpful. Use of these features may suggest or help exclude a diagnosis of acute cholecystitis in those patients in whom the cause of gallbladder wall thickening is otherwise not apparent.

Severe atypical molluscum contagiosum infection in an immunocompromised host

A case of severe molluscum contagiosum in a patient with treated thymoma is described. This unusual complication of immunosuppression is discussed and the literature on the subject reviewed.

Five new personality scales: their location in the factor space of personality measures

Five scales from a picture-preference test (PPT; Auld, 1981) and a sixth, provisional scale from this test, along with some of the best established factorial tests of personality and ability, were administered to 182 university students. The marker tests included the Eysenck Personality Questionnaire, Cattell's 16 Personality Factor Questionnaire, the Hakstian-Cattell Comprehensive Ability Battery, and measures of authoritarian personality traits, obsessionality, and Machiavellianism. In order to determine the factorial composition of the five PPT scales, we computed the correlations among the 53 variables, extracted the 12 significant factors by the principal axes method, and did a direct oblimin rotation. It was shown that three of the PPT scales loaded on a single factor, which was identified as P, Eysenck's "psychoticism." We concluded that the three PPT scales may prove useful as a non-questionnaire approach to measurement of P.

Angelchik antireflux device: computed tomography appearance

The Angelchik antireflux prosthesis is a silicon gel-filled, doughnut-shaped device with a tantalum tie strap that wraps around the gastroesophageal junction after reduction of a hiatal hernia. If dislodged, this prosthesis may produce a confusing picture on computed tomography, as it is of soft tissue density and may mimic a mass lesion. The computed tomography appearance of a normally placed prosthesis is demonstrated, and a case of prosthesis dislodgment diagnosed by computed tomography is reported.

Computed tomography of mesenteric disease

Inflammation, edema, and neoplasms may directly involve the mesentery. Here, the authors illustrate the varied CT appearances of such mesenteric abnormalities.

The cystic fibrosis locus

The identification of the cystic fibrosis locus (CF) provides a model for the study of single gene defects where the biochemical lesion is not known. Using families each of which has several affected siblings, it was possible to exclude a number of 'candidate genes' which had previously been proposed as possible sites of the CF mutation. Exclusion mapping of the genome using polymorphic protein and DNA markers showed that CF is on the long arm of human chromosome 7. The most closely linked flanking markers were identified, and human chromosome fragments containing them (and therefore the CF locus) were isolated in rodent cell lines by chromosome-mediated gene transfer. The transgenome was then analysed using cosmid contig mapping, pulse-field gel electrophoresis, HTF island identification and linkage disequilibrium. In this way, a candidate coding sequence has been identified which always segregates with CF.

Dissolution of mercury from amalgam into saline solution

Dissolution of mercury from amalgams and some intermetallic compounds found in the amalgam structure, such as gamma 1, gamma 2, and beta 1, was examined during one week of aging in 0.9% NaCl solution at 37 degrees C. The amount of mercury released from gamma 1 (30.2 micrograms/cm2) was at least 13 times that released from amalgam (0.5-2.2 micrograms/cm2) and five times that released from beta 1(5.7 micrograms/cm2). Gamma 2 released the least amount of mercury (0.46 micrograms/cm2). The study revealed that as high as 55% of the mercury ions liberated from the amalgams and the amalgam phases was adsorbed onto the walls of the vials in which the specimens were aged.

Broadband ultrasonic attenuation in the os calcis and single photon absorptiometry in the distal forearm: a comparative study

The measurement of broadband ultrasonic attenuation (BUA) in the os calcis has been described recently but the method has not been compared with other non-invasive techniques for the assessment of bone mass. We have compared the measurement of BUA in the os calcis with single-photon absorptiometry of the distal forearm in 44 subjects. A highly significant positive correlation was found between these two measurements (r = 0.80, p less than 0.001). Day to day repeatability was assessed for both techniques, with coefficients of variation of 3.9% and 1.4%, respectively, being obtained. Broadband ultrasonic attenuation appears to be a potentially useful bone measurement in the appendicular skeleton.

Etoposide pharmacokinetics in patients with normal and abnormal organ function

Precise guidelines for dose modification of etoposide in patients with hepatic dysfunction have not been determined. Etoposide pharmacokinetics were determined in 17 patients. Nine patients had bilirubin less than or equal to 1 mg/dL and eight had bilirubin ranging from 1.9 to 23 mg/dL. Twelve patients received etoposide 100 mg/m2 days 1, 3, and 5, in combination with cisplatin 70 mg/m2 or iproplatin 225 mg/m2 on day 1. Five patients received only one dose of etoposide. Etoposide was measured using a published high pressure liquid chromatography (HPLC) method which also quantitates picro etoposide and its hydroxy acid. Systemic clearance, Vdss and t1/2 beta averaged (+/- SD) 21.4 (+/- 7.4) mL/min/m2, 10.7 (+/- 4.1) L/m2, and 8.1 (+/- 2.8) hours in the nine patients with bilirubin less than or equal to 1 mg/dL, and 22.4 (+/- 9.6) mL/min/m2, 13.6 (+/- 11.3) L/m2, and 8.4 (+/- 3.9) hours in the eight patients with bilirubin 1.9 to 23.0 mg/dL. Stepwise multiple linear regression analysis of liver and renal function tests and other patient-specific variables identified creatinine clearance as the strongest predictor of etoposide systemic clearance (r2 = 40.8). Serum albumin was identified as the next strongest predictor, improving the r2 to 57.3%. Cumulative biliary excretion of unchanged etoposide and glucuronide or sulfate conjugates over 48 hours accounted for less than 3% of the dose in six patients studied. Toxicity occurred in patients with normal and abnormal bilirubin and was unrelated to etoposide clearance. Patients with total bilirubin 1.9 to 23 mg/dL, but creatinine clearance greater than 30 mL/min/m2 had etoposide clearance within the range for patients with normal liver function (16.8 to 35 mL/min/m2). Although these patients did not have reduced etoposide clearance, the major routes of etoposide non-renal elimination remain to be clearly defined. Additional patients should be evaluated to establish more precise guidelines for dosing etoposide in patients with abnormal liver function.

CT demonstration of myocardial perforation by a pacemaker lead

We report a case of perforation of the right atrium by a transvenous right atrial appendage pacemaker lead diagnosed by CT. Routine radiologic assessment was unable to demonstrate the perforation. Computed tomography is recommended in cases where pacemaker perforation is clinically suspected but not confirmed by conventional radiographic means.

Bacterial arthritis in an English health district: a 10 year review

Bacterial arthritis continues to present a difficult clinical and therapeutic problem, necessitating prompt diagnosis and intensive therapy. This study comprises a 10 year review of the condition in an English health district, with particular reference to aetiology, presentation, treatment, and outcome. Although the causative organisms remain qualitatively unchanged, increasing numbers of patients are elderly, immunosuppressed, or have underlying arthropathy. Factors which influence outcome include age, causative organism, joint involved, and delay in diagnosis. Attention is drawn to the notably poor outcome of hip infections in the elderly.

Psychoticism and creativity

Eysenck and Eysenck (1976) cited a number of studies showing that creativity and originality are associated with high scores on their Psychoticism factor, P. In this study, we examined the generality of this claim by using a different set of creativity measures, scales from the Comprehensive Ability Battery (Hakstian & Cattell, 1976) and the Eysenck Personality Questionnaire (Eysenck & Eysenck, 1975), with a sample of 173 students. No appreciable overlap was found between the creativity scales and P. A number of possible explanations for this result are discussed, and we concluded that this finding may cast doubt on the generality of the link between creativity and P.

Epiphyseal ossification centers in the assessment of fetal maturity: sonographic correlation with the amniocentesis lung profile

The epiphyseal ossification centers of the distal femur (DFE) and proximal tibia (PTE) appear and enlarge during the third trimester of pregnancy. Late in the third trimester, the epiphysis of the proximal humerus (PHE) begins to ossify in some fetuses. Using the amniocentesis lung profile to determine the value of sonographic epiphyseal visualization as a predictor of pulmonary maturity, we studied 50 fetuses prospectively and compared the sonographic epiphyseal findings with results from the amniocentesis lung profiles. Nine fetuses with a visible PHE had a mature amniocentesis lung profile (accuracy of positive prediction = 100%), and then fetuses with an immature amniocentesis lung profile had no visible PHE (conegativity = 100%). Fetuses in which the combined DFE and PTE diameters were greater than 11 mm or in which the DFE and the PTE diameters were similar in size (DFE less than or equal to 1 mm larger than PTE) also yielded positive results. Copositivity and accuracy of prediction of an immature amniocentesis lung profile, on the other hand, were low (22%-25%) for the same epiphyseal parameters. These data suggest that antenatal visualization and measurement of the epiphyseal ossification centers of the fetal knee and shoulder may help to identify fetuses that would have a mature amniocentesis lung profile.

Evaluation of the Singh index and femoral calcar width as epidemiological methods for measuring bone mass in the femoral neck

Epidemiological research into the causes of osteoporosis requires a validated radiological measure of bone mass. Ashing studies were carried out on 62 excised femoral heads, and a positive correlation was demonstrated between the weight to volume ratio of the ash and two radiological indices in the contralateral femoral neck: the Singh grade and the femoral calcar width. The repeatability and right-left concordance of the Singh grading method was also assessed. It is concluded that these radiological indices will provide useful epidemiological tools for the measurement of bone mass in the proximal femur.

Azathioprine hypersensitivity manifesting as acute focal hepatocellular necrosis

Images

Rectal spirochaetosis in homosexual men: characterisation of the organism and pathophysiology

Microbiological and electron microscopy studies were carried out on rectal biopsy specimens and faecal samples from eight practising male homosexuals and five heterosexual controls. Rectal spirochaetosis was present in five of the eight homosexual men. The organism was cultured and morphologically identified as a large anaerobic host associated treponeme. The degrees of infestation and depletion of microvilli were also measured. The results are discussed in relation to the possible clinical importance of rectal spirochaetosis.