Mechanical instability as a cause of gait disturbance in high-grade spondylolisthesis: a pre- and postoperative three-dimensional gait analysis

Mechanical instability of the spinopelvic junction is a suspected cause of abnormal gait in high-grade spondylolisthesis. Computerized three-dimensional gait analysis was performed on a 10-year-old with grade III spondylolisthesis at L-5. Preoperatively, the gait pattern was characterized by posterior pelvic tilt, decreased hip flexion, increased knee flexion, and decreased stride length and walking speed. All temporal and kinematic parameters of gait normalized after laminectomy and instrumented, in situ arthrodesis (L-4-S-1). The absence of any neurologic abnormalities on preoperative imaging, intraoperative somatosensory-evoked potentials (SSEP) monitoring, and nerve-root exploration, together with the observed improvement after stabilization of the spinopelvic junction, suggests a mechanical basis for the gait changes in high-grade spondylolisthesis.

A rat model to study hypercalcemia-induced acute pancreatitis

Hypercalcemia causes acute pancreatitis in humans, a phenomenon reproduced experimentally in cats and guinea pigs. Because the rat is the most frequently used animal for the study of experimental pancreatitis, the present studies were performed to evaluate the effects of hypercalcemia in the rat. In in vitro studies, pancreatic lobules were prepared from fasted Wistar rats (200-250 g) and incubated in HEPES bicarbonate-buffered medium (pH 7.4) containing 0, 0.6, 1.2, 2.5, 5, and 10 mM CaCl2 with or without carbachol 10(-6) M. Amylase was measured in the medium after 30 min to 3 h, and expressed as percent of total amylase. In in vivo studies, fasted male Wistar rats (300-400 g) received calcium (CaCl2; 0.6 mmol/kgh) into the tail vein for 12 h. Control animals received NaCl 0.9% infusion. Histologic slides (H&E-stained) were evaluated in a blinded fashion. Pancreatic lobules showed a higher basal amylase output when incubated in higher calcium medium. The largest, significant difference (2.6-fold) was between 0.6 and 5 mM medium CaCl2 (p < 0.05). Carbachol-stimulated amylase release was again higher with increasing medium calcium with the most pronounced difference (1.3-fold) between 0.6 and 2.5 mM CaCl2 (p < 0.05). In vivo calcium-treated animals showed accumulation of zymogen granules in the cytoplasm, cytoplasmic vacuolization, focal acinar cell depolarization, acinar necrosis, and edema. Calcium causes amylase release from rat pancreatic lobules in vitro. Higher medium calcium levels both significantly increase amylase release from unstimulated and carbachol stimulated lobules. Twelve-hour in vivo calcium infusion leads to accumulation of zymogen granules in acinar cells and acinar injury.(ABSTRACT TRUNCATED AT 250 WORDS)

[The use of nonpathogenic leptospira as diagnostic antigens for the diagnosis of leptospira infections in cattle]

The seroprevalence of leptospira antibodies was determined in 4377 bovine sera by microagglutination assay using 11 Leptospira interrogans serovars. In 10% (439 samples) of the sera, a positive reaction was detected. These included 275 sera (62.6%) with reaction to L. grippotyphosa, 159 (36.2%) to L. saxkoebing and 5 (1.1%) sera with reactions to other serovars. Multiple reactions were found in 9.8% of the 439 positive sera, whereby the Sejroe group dominated (65%) within the possible combinations of crossreactions. To determine the suitability of nonpathogenic strains as polyvalent diagnostic antigens, two L. biflexa serovar patoc strains were compared with the above-mentioned 11 L. interrogans serovars in microagglutination testing of 1995 screen sera. The sensitivity of the test was found to be 0.3% and the specificity was 80.3%. Using the two L. patoc strains, all of the 415 positive field sera and 11 positive control sera yielded negative reactions. Based on these results, the use of L. biflexa serovar patoc cannot be recommended as polyvalent antigen in the diagnosis of bovine leptospirosis by microagglutination.

Green Spring criteria for medical necessity of outpatient treatment and its use in a mental health utilization review program

The authors have developed a two-tiered method for utilization review of outpatient mental health services. The methodology looks at initial and continued treatment evaluation and uses diagnosis, symptoms, plan of treatment, and the Global Assessment Scale (GAS) among other indicators to determine appropriateness of treatment. Preliminary program experience has been positive and is included.

Changes in upper airway muscle activation and ventilation during phasic REM sleep in normal men

Several investigators have observed that irregular breathing occurs during rapid-eye-movement (REM) sleep in healthy subjects, with ventilatory suppression being prominent during active eye movements [phasic REM (PREM) sleep] as opposed to tonic REM (TREM) sleep, when ocular activity is absent and ventilation more regular. Inasmuch as considerable data suggest that rapid eye movements are a manifestation of sleep-induced neural events that may importantly influence respiratory neurons, we hypothesized that upper airway dilator muscle activation may also be suppressed during periods of active eye movements in REM sleep. We studied six normal men during single nocturnal sleep studies. Standard sleep-staging parameters, ventilation, and genioglossus and alae nasi electromyograms (EMG) were continuously recorded during the study. There were no significant differences in minute ventilation, tidal volume, or any index of genioglossus or alae nasi EMG amplitude between non-REM (NREM) and REM sleep, when REM was analyzed as a single sleep stage. Each breath during REM sleep was scored as "phasic" or "tonic," depending on its proximity to REM deflections on the electrooculogram. Comparison of all three sleep states (NREM, PREM, and TREM) revealed that peak inspiratory genioglossus and alae nasi EMG activities were significantly decreased during PREM sleep compared with TREM sleep [genioglossus (arbitrary units): NREM 49 +/- 12 (mean +/- SE), TREM 49 +/- 5, PREM 20 +/- 5 (P less than 0.05, PREM different from TREM and NREM); alae nasi: NREM 16 +/- 4, TREM 38 +/- 7, PREM 10 +/- 4 (P less than 0.05, PREM different from TREM)]. We also observed, as have others, that ventilation, tidal volume, and mean inspiratory airflow were significantly decreased and respiratory frequency was increased during PREM sleep compared with both TREM and NREM sleep. We conclude that hypoventilation occurs in concert with reduced upper airway dilator muscle activation during PREM sleep by mechanisms that remain to be established.

Evaluation of five different methods for routine diagnosis of rabies

Brain tissue from 187 animals of different species was investigated by means of fluorescent antibody test, peroxidase anti-peroxidase technique, mouse inoculation test and cell culture technique for a diagnosis of rabies. With peroxidase anti-peroxidase technique the rabies specific reaction comprised inclusion bodies and a granular staining of the cytoplasm of affected cells. A specific positive reaction was found only in neurons, in which perikaryon as well as cell processes were affected. Fluorescent antibody test and peroxidase anti-peroxidase technique detected 98% each, mouse inoculation test 95% and cell culture technique 81% of the rabies positive animals. In conclusion, peroxidase anti-peroxidase technique allows a highly reliable diagnosis of rabies when only formalin-fixed and paraffin-embedded material is available. Histopathological alterations comprising Negri bodies, inflammatory and degenerative lesions were encountered in 53% of the rabies positive brains.

Freud, Fliess, and the nasogenital reflex: did a look into the nose let us see the mind?

Wilhelm Fliess, a Berlin nose and throat surgeon, and Sigmund Freud, the father of psychoanalysis, collaborated to treat one of Freud's earliest patients, Emma Eckstein. The basis for the treatment was their belief in the "Nasogenital Reflex," a widely accepted theory that has disappeared from the literature of otolaryngology. The outcome of Emma's treatment may have profoundly altered the history of psychiatry, by suggesting the role of the unconscious and the existence of the Oedipus complex.

Differences in IgG1 and IgG2 responses of cattle infected with Coxiella burnetii and following vaccination

Vaccination of 115 cattle with a formalin-inactivated Coxiella burnetii (Phase II) vaccine selectively induced a highly significant IgG2 response detectable by enzyme-linked immunosorbent assay. High IgG2 and negative or cut off IgG1 levels could be detected in uninfected cattle, whereas significant IgG1 but lower IgG2 levels were associated with C. burnetii infections.

Taurocholate is more potent than cholate in suppression of bile salt synthesis in the rat

Synthesis of bile salts is regulated through negative feedback inhibition by bile salts returning to the liver. Individual bile salts have not been distinguished with regard to inhibitory potential. We assessed inhibition of bile salt synthesis by either cholate or its taurine conjugate in bile fistula rats. After allowing synthesis to maximize, baseline synthesis was determined by measuring bile salt output in four consecutive 6-hr periods. Next, sodium cholate (+[(14)C]cholate) or taurocholate (+[(14)C]taurocholate) was infused into the jugular vein for 36 hr and bile was collected in 6-hr aliquots. Hepatic flux of exogenous bile salt was determined by measuring output of radioactivity in bile divided by specific activity of the infusate. Synthesis was determined during the last four 6-hr periods of infusion by subtracting exogenous bile salt secretion from the total bile salt output. Thirteen studies using cholate and 13 using taurocholate were performed. Hepatic flux of infused bile salt varied from 1 to 12 micro mol/100 g per rat per hr. Percent suppression of synthesis varied directly with hepatic flux of exogenous bile salt for both cholate and taurocholate in a linear fashion (r = 0.66, P < 0.01 and r = 0.87, P < 0.0005, respectively). Slope of the taurocholate line was 7.82 (% suppression/ micro mol per 100 g per hr), while slope of the cholate line was 3.66 (P < 0.05), indicating that taurocholate was approximately twice as potent as cholate in suppression of synthesis. At fluxes of 10-12 micro mol/100 g per hr, taurocholate suppressed synthesis 84 +/- 8 (SEM) % while cholate suppressed synthesis only 42 +/- 12% (P < 0.02). The x-intercept of the taurocholate line was 0.65 ( micro mol/100 g per hr), while that of the cholate line was -1.01 (NS) suggesting that the threshold for initial suppression of synthesis did not differ for these two bile salts. We conclude that taurocholate is a more effective inhibitor of hepatic bile salt synthesis than cholate, and that intestinal deconjugation of bile salts may play a role in the regulation of synthesis.-Pries, J. M., A. Gustafson, D. Wiegand, and W. C. Duane. Taurocholate is more potent than cholate in suppression of bile salt synthesis in the rat.

Photochemical rearrangement of diene endoperoxides

It has been shown that the direct irradiation of cyclic peroxides such as ascaridole, and those derived from cyclohexadiene, 1,3,5,5-tetramethylcyclohexadiene, and levopimaric acid methyl ester rearrange on irradiation. The bisepoxides are obtained, as in the thermal rearrangement, together with, where the structure permits, the ketoepoxide. The reaction can be induced by triplet–triplet energy transfer.