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Biomedical subjects

S D Johnson

Publications and source records attributed to S D Johnson.

34 records · Page 2Linked to original sources
PubMed1989

Epidemiology of insulin dependent diabetes before age 20 in Wisconsin, with particular reference to seasonality.

Physicians in the State of Wisconsin were contacted by mail and asked to report all cases of diabetes in patients under 20 yr diagnosed between 1 July 1982 and 30 June 1984 in order to study factors associated with seasonality in insulin-dependent diabetes mellitus (IDDM). Wisconsin's population is fairly homogeneous and is primarily middle socioeconomic class, small-town or rural, and of northern European Caucasian descent. The incidence of IDDM in winter was higher than in summer during the first year of the study, similarly to results of other studies. However, there was no significant winter peak in diagnosis during the second year. When monthly incidence rates from both years were combined, the increased evidence of IDDM in winter vs. summer was evident in males, but not in females. There appeared to be a spike in the number of new cases of IDDM in the first year of the study which was more evident in males. Such a spike is consistent with spikes in the incidence of IDDM occurring about the same time in Europe and in North America. The percentage of patients with antibody titres to Coxsackie virus and mycoplasma pneumoniae diagnosed during the first winter's peak were equal to those in nondiabetic controls. The distributions of HLA DR types of patients diagnosed in winter were no different from diabetics diagnosed in other seasons. The distribution of HLA DR types (5% DR2, 55% DR3, 82% DR4 and 38% DR3DR4) were similar to those of other groups of Caucasian subjects with IDDM. Also similarly to other studies of IDDM, 14% of the patients had thyroid microsomal antibody titers. The results of this study support the previously-advanced idea that winter might precipitate overt carbohydrate intolerance in individuals in whom insulin cell destruction is already well established (Diabetes, 36, 265-268, 1987). If this is true, studies of seasonality in IDDM might not be informative about the causation of IDDM.

Adolescent↗
PubMed1988

The diagnosis of temporomandibular joint disease: two-compartment arthrography and MR.

The reliability and accuracy of two-compartment temporomandibular joint (TMJ) arthrography was compared with MR imaging on the basis of an analysis of surgical findings obtained from joints that had been studied preoperatively with arthrography or MR or, in some cases, both procedures. Seven hundred forty-three consecutive TMJ arthrograms were successfully obtained in a total of 443 patients by using a single 27-gauge needle and a two-compartment technique in each joint. There was a 100% correlation with surgical findings in 218 radiologically abnormal joints operated on within 90 days of arthrography with respect to the presence or degree of meniscus displacement and normal or abnormal disk morphology and function. In 604 patients 1052 TMJs were studied with high-field-strength surface-coil MR. Surgical findings were available for correlation in 170 of the joints studied. Forty-three joints were studied with both two-compartment arthrography and MR. Eight operated joints had been imaged successfully with both two-compartment arthrography and MR. Both methods of evaluation provided highly reliable and accurate information regarding meniscus position and shape. Arthrography was superior to MR in detecting capsular adhesions and the presence or absence of perforation of the disk or meniscus attachments. Simple meniscectomy (with or without insertion of a temporary Silastic TMJ implant) was the most frequently performed surgical procedure in the series, followed by meniscus repositioning procedures. Joint effusions, failed TMJ implants, and avascular necrosis were demonstrated best with MR. Soft-tissue lesions, including intrinsic degeneration of the meniscus, anomalous muscle development, muscle atrophy, tendinitis, and injuries such as contusions and hematomas, were demonstrated only with MR. Partial-flip-angle GRASS (gradient-recalled acquisition in the steady state) techniques permit both fast scanning and study of functional joint dynamic. Joint fluid may appear as high signal intensity on GRASS images because of T2*-weighting. We recommend MR as the procedure of choice for diagnosis of uncomplicated internal derangements of the TMJ. Two-compartment arthrography with videofluoroscopy is an important ancillary procedure that should be performed whenever capsular adhesions or perforations are suspected and not demonstrated with MR and whenever MR is inconclusive.

Arthrography↗
PubMed1981

Carbon-13 nuclear magnetic resonance spectroscopic study of teichuronic acid from Micrococcus luteus cell walls. Comparison of the polysaccharide isolated from cells with that synthesized in vitro.

Teichuronic acid isolated from the cell walls of Micrococcus luteus has been examined by natural-abundance (13)C NMR spectroscopy. Proton-decoupled and proton-coupled spectra were obtained for native teichuronic acid and also after the teichuronic acid had been oxidized with periodate and reduced with borohydride. The spectra are consistent with the structure [ManNAcUAp-( beta -1,6)-G1cp-( alpha -1,4)]n. Teichuronic acid synthesized in vitro from suitable substrates by the particulate enzyme fraction obtained from M. luteus yielded a (13)C NMR spectrum which is indistinguishable from that of the native teichuronic acid, indicating a structural identity of the teichuronic acid synthesized in vitro with that isolated from cell walls.

Cell Wall↗
PubMed1980

Anterior cervical discectomy without fusion: long-term results.

The long-term follow-up of patients operated by one surgeon by simple anterior discectomy without fusion have been presented. The results are much better in patients with soft extruded discs than with painful discs or degenerative discs with varying degrees of radiculopathy or myelopathy. The same statement can be made for the posterior approach. The anterior approach appears to be superior for soft central extruded discs compressing the spinal cord. There appears to be a greater incidence of another disc at an adjacent level with the anterior approach than when the operation is done posteriorly. The anterior operation is an easier surgical procedure than the posterior operation in the average surgeon's hands; otherwise, it would not be as popular as it is. Interbody fusion has no long-term advantages over simple discectomy. Complications of the anterior approach, particularly with fusion, appear greater than the limited posterior approach. Rather than continue the controversy over the anterior vs. the posterior approach, it is recommended that each surgical case be evaluated to determine the preferred approach. With the passage of time, I have preferred to operate the C4, 5, and 6 ruptured discs anteriorly, as well as all central discs or hard central cervical spondylotic bars. This seems preferable to the extensive laminectomy recommended by many for spondylotic myelopathy. However, the anterior approach has been limited to two spaces rather than multiple spaces. On the rare occasions when an extensive decompression of the cervical canal is indicated, the posterior approach has been chosen. In addition, the C7 or rare T1 soft ruptured disc have been done posteriorly. When there is a doubt about the diagnosis, e.g., when a tumor is suspected or a multiple root defect associated with atypical findings on myelography, the posterior approach is preferred.

Chronic Disease↗
PubMed1980

Reverse discrimination and aggressive behavior.

Aggression of each of 32 white male and female university students toward an opponent who had just defeated him in a competition was assessed in a 2 X 2 experiment design in which the winning opponent was either a black or a white and the loss was for one or two reasons: because the opponent 1) was economically deprived or 2) had superior ability. It was assumed that those Ss who had lost to a black opponent because this person was economically deprived experienced reverse discrimination based on race. Results indicated that white Ss were more aggressive toward a black when the loss was based on economic deprivation (reverse discrimination) than towards a white when the loss was due to economic deprivation (an arbitrary loss but not based on race), whereas white Ss were less aggressive towards a black opponent than towards a white opponent when the Ss lost because of the other's superior ability. The practical and theoretical implications of these results are discussed.

Aggression↗
PubMed1979

Altered coagulation after albumin supplements for treatment of oligemic shock.

Coagulation and need for postoperative blood and plasma therapy were studied in 94 injured patients requiring massive transfusions (average = 14.4); 46 patients, by random selection, received supplemental albumin. Albumin therapy increased total protein concentration (6.4 vs 5.8 g/dL), serum albumin level (4.2 vs 2.9 g/dL), and plasma volume (3,895 vs 3,579 mL) but not RBC volume (1,520 vs 1,530 mL). During the initial five postoperative days, patients receiving albumin required more transfusions (7.1 vs 3.8) and plasma (455 vs 317 mL). This increased need for blood and plasma correlated with a significant decrease in fibrinogen (238 vs 405 mg/dL) and prolongation of the prothrombin time (2.6 vs 1.4 seconds). The partial thromboplastin time was prolonged and the platelet concentration was decreased in albumin-treated patients, but not significantly. Deficiencies in specific coagulation factors have not yet been identified but are being studied. Impaired coagulation is another potential hazard of supplemental albumin therapy, which is probably contraindicated in injured patients.

Adult↗
PubMed1978

Pulmonary effects of albumin resuscitation for severe hypovolemic shock.

The effect of albumin when added to the resuscitation regimen of patients in hypovolemic shock was studied in a randomized prospective manner in 52 injured patients who received an average of 15.3 transfusions, 9.6 liters of balanced electrolyte solution, and 980 ml of fresh frozen plasma. Before and during operation, 27 patients received an average of 25 gm of albumin and 150 gm/day for three to five days. Patients who received albumin had greater dependence on respiratory support, averaging eight days while receiving ventilatory support with volume ventilator compared with three days in patients not receiving albumin. Furthermore, patients receiving albumin had forced inspiratory oxygen/Pao2 ratios that were statistically and significantly higher than those of patients not receiving albumin during all phases of their hospital course. These effects were associated with increased plasma volumes caused by the oncotic effects of albumin and by its interference with saline diuresis. On the basis of this preliminary report, albumin seems to have a detrimental effect on respiratory function.

Adult↗
PubMed1978

Alcohol and rape in Winnipeg, 1966-1975.

Either victim or rapist or both were drinking prior to 72% of the rapes occurring in Winnipeg from 1966 through 1975, and the presence of alcohol increased the likelihood that the victim would be injured prior to sexual intercourse.

Adult↗