Interpretation of intraocular and serum antibody levels in necrotizing retinitis

BACKGROUND: Intraocular antibodies have been measured as a diagnostic aid in necrotizing retinitis but interpretation of results may be difficult. METHODS: Vitreous or aqueous and serum immunoglobulin G antibodies to toxoplasmosis, cytomegalovirus, herpes simplex virus I and II, and varicella zoster virus were subjected to enzyme-linked immunosorbent assay in 27 patients with necrotizing retinitis and 15 control patients. A quotient was derived quantitating the amount of excess antibody in the eye compared to serum. Different interpretative rules were analyzed to determine which yielded the highest sensitivity and specificity. RESULTS: The highest intraocular antibody relative to serum among the 4 antibodies correctly predicted the final clinical diagnosis in 21 of 27 patients, for a sensitivity of 78% and a specificity of 90%. Interpretive rules that relied on a high numeric value of the antibody quotient or did not consider the relative ranking of the four antibody quotients were less sensitive and specific because multiple antibodies were detected in most eyes. The technique was safe and rapid. CONCLUSION: Interpretation of antibody titers in intraocular fluids is facilitated by testing several relevant antibodies and comparing the results. The technique may be helpful to diagnose necrotizing retinitis and to ascertain viral cause in acute retinal necrosis.     

Bond strengths and SEM evaluation of Clearfil Liner Bond 2

PURPOSE: To evaluate a dental adhesive system that uses a single conditioning/primer agent. MATERIALS AND METHODS: Twenty-five flat enamel and dentin bonding sites were prepared to 600 grit on human molar teeth. The Clearfil Liner Bond 2 adhesive system was used to bond Clearfil AP-X composite to both enamel and dentin. After 24 hours of water storage, shear bond strengths were determined using an Instron testing machine. Fifty V-shaped cavity preparations were prepared in human molar teeth with an enamel and cementum margin. Composite restorations were placed using the new adhesive system. The teeth were stored for 24 hours, thermocycled, stained with AgNO3 , sectioned and examined for microleakage. SEM examinations were also completed to evaluate the effects of the treatment steps on enamel and dentin surfaces. RESULTS: Mean shear bond strengths for the experimental adhesive to enamel and dentin were 28.2 +/- 4.9 and 19.4 +/- 3.1 MPa. A t-test revealed that the enamel bond strength was significantly greater (P<0.05) than the dentin strength. No marginal leakage was observed from the enamel margins of the restorations. Three restorations showed minimal leakage from the cementum margins. SEM examinations showed resin penetration into both the conditioned enamel and dentin surfaces. The adhesive system produced high bond strengths to both enamel and dentin, exhibited very minimal microleakage and was easy to use.     

Achieving and maintaining compliance with the ketogenic diet

The ketogenic diet, a treatment for intractable epilepsy, is rarely initiated because it requires strict compliance with a diet that is perceived to be unpalatable. In a case study of a 15-year-old girl with uncontrolled epilepsy, we used a stimulus-choice procedure to assess relative preferences of 33 foods from the diet and to develop two treatments based on Premack's principle. The results of a multielement analysis showed that both treatments increased dietary compliance. Compliance was maintained with generalization of treatment across settings, and was associated with a 40% reduction in seizures.     

Nitric oxide-synthesising neurons in the central subnucleus of the nucleus tractus solitarius provide a major innervation of the rostral nucleus ambiguus in the rabbit

We describe an intramedullary nitric oxide synthase (NOS) neural pathway that projects from the nucleus tractus solitarius (NTS) to the rostral nucleus ambiguus (NA) in the rabbit. With the use of NADPH diaphorase histochemistry and NOS immunohistochemistry, a compact group of NOS-positive perikarya was identified in the central subnucleus of the NTS dorsomedial to the tractus solitarius and rostral to the obex. A dense network of NOS terminals was seen in the rostral NA. We investigated whether NOS terminals in the NA derive from NOS perikarya in the central NTS and whether the central NOS pathway links esophageal afferents and efferents. In some rabbits, the central NTS was unilaterally lesioned. In others, Phaseolus vulgaris-leucoagglutinin (PHA-L) was injected into the central NTS, or cholera toxin-gold was injected into the NA, or cholera toxin-horseradish peroxidase (HRP) was injected into the wall of the esophagus. The medulla was subsequently processed to demonstrate PHA-L, cholera toxin-gold, HRP, and NOS reactivity. Seven days after the NTS lesion, we observed a marked decrease in the density of NOS terminals in the ipsilateral NA. After injection of PHA-L into the central NTS, a dense group of PHA-L fibres was seen in the rostral NA, principally ipsilaterally. Afferent fibres from the esophagus were found around the NOS cell bodies in the central NTS, and many of these NOS neurons were double labeled with cholera toxin-gold after injection of this tracer into the NA. NOS terminals were found around NA neurons that were retrogradely labelled from the esophagus. We conclude that the NOS neurons in the central NTS act as interneurons in a central pathway connecting esophageal afferents and efferents.     

The effect of calcipotriol on lesional fibroblasts from patients with active morphoea

We examined the responsiveness of cultured dermal fibroblasts from biopsies of 6 patients with active morphoea and a similar number of matched controls to the cell proliferation inhibition activity of calcipotriol. Cultured fibroblasts from controls showed no significant response to calcipotriol (at concentrations of 1 x 10(-8) to 1 x 10(-4) M). However, calcipotriol did inhibit the proliferation response of morphoea fibroblasts at all concentrations when compared with controls. There was 4- to 20-fold inhibition in 2 of the morphoea patients when compared with control samples. Four other morphoea samples showed inhibition but to a lesser extent compared with controls.     

Routine microbiological testing in sudden and unexpected infant death

We reviewed 187 depth recorded seizures in 33 patients with non-lesional temporal lobe complex partial seizures. All patients had a minimum of 1 year follow-up following temporal lobectomy. We classified seizure onset pattern as rhythmic activity, attenuation, or repetitive spikes or spike wave complexes. The most common pattern of seizure onset was rhythmic activity and the next most common pattern was repetitive spikes. Seventy-five seizures (49%) had only one seizure onset pattern, and 79 seizures (51%) had a combination of seizure onset patterns. The degree of hippocampal gliosis strongly predicted the type of seizure onset pattern (Chi square = 24.07, 2 d.f., P < 0.01). The rhythmic activity pattern was associated with mild gliosis, and the repetitive spike pattern was associated with severe gliosis. We classified seizure onset as focal or regional based on the number of electrode contacts that were involved by the ictal EEG. A focal seizure onset was associated with an excellent outcome following temporal lobectomy.     

Digital calcification in systemic sclerosis: effective treatment with good tissue preservation using the carbon dioxide laser

Tissue calcification of the fingers associated with limited systemic sclerosis is a common problem and is the source of considerable morbidity as it may be extremely tender and cause considerable functional disability. The current treatment of digital calcification is unsatisfactory. We evaluated the use of the carbon dioxide (CO2) laser in the management of this condition in six patients with the limited form of systemic sclerosis. A total of 21 areas of symptomatic digital calcification of the fingers were treated. Complete resolution of symptoms occurred in 12, moderate response with partial improvement was seen in five, little improvement was observed in two, and recurrence of calcinosis was found in two. The patient's average healing time was 6 weeks (range 4-10). The median duration of follow-up was 20 months (range 12-40). Postoperative infection was seen in two patients, and resolved completely in both with the use of topical and oral antibiotics. We found the CO2 laser a simple and effective treatment for most of the symptomatic lesions of digital calcification, and it may obviate the need for deforming surgery in many cases.