Cerebral microhemorrhage in Marchiafava–Bignami disease detected by susceptibility-weighted imaging

Marchiafava–Bignami disease (MBD) is a rare alcohol-associated disorder. Clinical features include not only disturbed consciousness, dysarthria, tetraparesis, astasia-abasia, and symptoms of interhemispheric disconnection as initial symptoms but also cognitive deficits as clinical outcomes. The clinical significance of cerebral microhemorrhage (CMH) has been recognized in patients with cognitive deficits; however, the presence of CMH in patients with MBD has not been emphasized. The aim of the present study was to clarify the relationship between CMH and MBD. For this purpose, we report four patients with MBD, who showed asymmetrical hypointense areas in multiple cortico-subcortical regions on susceptibility-weighted imaging (SWI). All cases had a history of chronic alcohol abuse and symmetrical lesions in the entire corpus callosum. These patients’ clinical symptoms included not only coma, dysarthria, and astasia-abasia as initial symptoms but also dementia as a clinical outcome. SWI showed asymmetrical hypointense areas in the multiple cortico-subcortical regions, indicating the presence of CMH. Compared with patients with normal cognitive function, demented patients showed higher severity of CMH. Our report would indicate that CMH is an important factor indicating the severity of dementia in patients with MBD.     

Ethylmaltol Odor Enhances Salivary Hemodynamic Responses to Sucrose Taste as Detected by Near-Infrared Spectroscopy

The perceived intensity of the taste of a food is enhanced only if the odor of the food is perceptually similar to the taste. For example, a caramel-like odor enhances the perceived intensity of sweetness. The way gustatory and olfactory signals are integrated in the brain depends largely on one’s previous experiences with taste and odor pairings. To elucidate the effects of a sweet, sugary odor, ethylmaltol, on sucrose taste, as perceived by the central integration of flavor, we recorded salivary hemodynamic responses to the odor and taste pairings using near-infrared spectroscopy (NIRS) of seven panelists. First, we observed concentration-dependent increases in the amplitude of the responses to 0 to 6 % sucrose solutions. Second, when ethylmaltol odor was added to a 4 % sucrose solution, we observed a significant increase in the amplitude of the responses from all panelists. The addition of ethylmaltol to a tasteless solution caused no significant change in the amplitude of the salivary hemodynamic response. These results indicate that the sweet odor of ethylmaltol enhances the salivary hemodynamic response when combined with a sweet taste. Therefore, a congruent combination of sweet odor and taste greatly enhances salivary responses, which are dependent on the central integration of odor and taste.     

Enzyme Immunoassay for Mabuterol,A Selective β2-Adrenergic Stimulant in the Trachea

A sensitive double antibody and heterologous enzyme immunoassay for mabuterol was established. For competitive reactions, antibody raised against diazotized mabuterol-human serum albumin was incubated with a mixture of diazotized mabuterol analog (RC-1) labeled with β-D-galactosidase and standard or sample. Free and antibody-bound enzyme hapten were separated using anti-rabbit IgG immobilized on polystyrene balls. Activity of the enzyme on the solid phase was fluorometrically determined. The present immunoassay allows detection of 0.5 to 100 pg/tube of mabuterol.

Pharmacokinetic behavior of this agent in human plasma and urine was studied after a single oral administration (50 yg). The maximum level was achieved after 2–3 hrs with approximately 280 pg mabuterol /ml of plasma and the half life of mabuterol was estimated to be 19.5 hrs. Cumulative amount of mabuterol in the first 72 hrs urine was 64.3 ± 13.2% of the administered dose.     

A Single Intraduodenal Administration of Human Adenovirus 40 Vaccine Effectively Prevents Anaphylactic Shock

Vaccine administration into the intestine is known to induce mucosal tolerance most efficiently. Therefore, developing a delivery system that targets the intestinal mucosa is expected to improve the efficiency of immunosuppression. Human enteric adenovirus serotype 40 (Ad40)-based vectors have the advantage of targeting intestinal mucosa, making them prime candidates as mucosal vaccine carriers for immunosuppression. Here, after both oral and intraduodenal administrations, the vector distribution of replication-defective recombinant Ad40 vectors (rAd40) was significantly higher than that of a conventional Ad vector based on human adenovirus 5 (Ad5) in ilea containing Peyer''s patches. Single intraduodenal administration of rAd40 induced antigen-specific mucosal immunoreaction mediated by intestinal mucosal and systemic immunity. In ovalbumin-induced allergy mouse models, this approach inhibited antigen-specific delayed-type hypersensitivity reactions, diarrhea occurrence, and systemic anaphylaxis. Thus, a single intraduodenal administration of rAd40 provides a potent method of inducing allergen-specific mucosal tolerance and a new allergen-specific immunotherapy for overcoming problems with current therapies against life-threatening allergic reactions, including anaphylaxis.     

Composite polymerization stress as a function of specimen configuration assessed by crack analysis and finite element analysis

Objectives

To test the null hypothesis that polymerization-induced stress was not influenced by cavity dimensions and geometries.

Methods

Four experimental groups, with different C-factors and specimen volumes were defined using bottom-less glass disks (height: 1 or 2 mm) with a central hole 3 or 6 mm in diameter, and 3 mm wall thickness. Another four groups were created by bonding a glass plate to the bottom of the disks. Additionally, disks with 2-mm height, 3 mm in cavity diameter, and 4.5-mm thick walls were prepared. Vickers indents (9.8 N, 20 s) were made at the top surface at 600 μm from the cavity margin. The lengths of the indentation diagonal and the corner cracks parallel to the cavity margin were measured. Ten minutes after restoration (Majesty Esthetic, Kuraray), cracks were re-measured. Stresses at the indent site were calculated based on glass fracture toughness and increase in crack length. Data were subjected to ANOVA/Tukey or Kruskal–Wallis/Mann–Whitney tests (alpha: 5%, n = 8). Finite element analysis (FEA) was used to estimate stress at the interface and the effective structural rigidity of the substrate.

Results

Overall, for experimental and FEA results, cavities developed higher stress than bottom-less disks. Increasing wall thickness did not affect stress. When similar geometries and C-factors were compared, higher volumes developed higher stress and had greater incidence of margin cracking.

Clinical significance

C-factor is a suitable predictor for polymerization stress in low compliance environments, particularly due to its simplicity. However, the influence of cavity size cannot be disregarded especially for the development of marginal cracking. The interaction between size, geometry and stiffness is likely to become more complex according to the complexity of the cavity shape.     

Bone temperature elevation by drilling friction and neurological outcome in the cervical spino-laminoplasty

Background

Drill-induced heat has been suspected as a cause of tissue injury, and there are ample experimental data to substantiate the implication. However, no clinical results have been presented with measurement of temperature in the vicinity of neural structures during the actual spinal procedures.

Methods

Using a thermocouple, temperature in the gutters drilled in the midline and the lateral margins of the lamina was monitored closely in 61 patients, who underwent the French-door style of cervical spino-laminoplasty. The drilling was performed intermittently for a duration of 5 or 10 seconds, using 3- or 5-mm diamond burrs with sufficient continuous cooling irrigation. The correlations between bone temperature elevation and postoperative sensorimotor symptoms were then analyzed.

Results

In the lateral gutters at the most cephalad level (typically C3), where the drilling was performed underneath an overlying bundle of muscle attached to C2's spinous process, the temperature rose significantly. This occurred even with 5-second drilling sessions. The average peak temperature was 44 °C at this level. At all other sites, the temperature was maintained below 40 °C. In three patients, transient neurological deficit developed postoperatively, which did not correlate with the incidence of bone temperature elevation.

Conclusions

Intermittent drilling with sufficient irrigation can prevent thermal neuronal damage generated by high-speed drills. Drilling with small diamond burrs in deep and narrow spaces covered by overlying muscles predisposes to inadequate irrigation and thermal elevation. Continuous, protracted drilling without frequent irrigation may result in excessive heat generation and nerve injury.