Computed tomography of the brain in the Smith-Lemli-Opitz syndrome

Computed tomographic (CT) scans of the brain in a child with Smith-Lemli-Opitz syndrome revealed enlargement of the ventricular system, hypoplasia of the cerebellum, and abnormal thickening of the gray matter, consistent with pachygyria. These findings have been previously noted in autopsies performed on patients with this disorder. We conclude that CT scanning is a valuable tool in the evaluation of children suspected of having the Smith-Lemli-Opitz syndrome.     

Localization of epileptogenic foci using a simple reference-subtraction montage to document small interchannel time differences

We present a modified EEG montage that detects small interchannel time differences and assists in localizing the epileptogenic focus. Regions with apparently synchronous epileptic discharges are displayed simultaneously in referential and subtraction derivations. The subtraction derivation is a bipolar configuration of two regions of interest that are not necessarily adjacent. The referential derivation reveals the polarity, voltage, and morphology of the two discharges, and the subtraction derivation detects asynchrony; the combined reference-subtraction derivation thus indicates the region that is activated first.     

Transarterial embolization of vein of Galen aneurysmal malformation after unsuccessful stereotactic radiosurgery

The authors present three cases of vein of Galen aneurysmal malformations (VGAMs) diagnosed in infancy and submitted by the referring teams for stereotactic radiosurgery as the initial therapy (therapeutic doses ranging between 20–25 Gy and 40–50 Gy to the peak dose). After the conventional follow-up of 18–24 months, no change could be detected in the angioarchitecture of the lesions. All three cases were then referred for endovascular treatment and underwent embolization by the transarterial route using liquid adhesives (N-butyl cyanoacrylate). This resulted in complete anatomical exclusion of the lesion. Regardless of the theoretical efficiency of radiosurgery in the management of brain arteriovenous malformations, the present authors believe that transarterial embolization remains the treatment of choice in VGAMs. It offers a high rate of morphological cure and the best chances for normal neurocognitive development. The time required by radiosurgery to achieve a significant result is too long for developing and maturing brain and may not prevent the negative effects of the lesion, mainly in regard to hemo- and hydrodynamic disorders (atrophy, subcortical calcifications, etc.) created by the VGAM, thus leading to irreversible mental retardation.     

Immunomodulation in mice by Bacillus megaterium and its dependence on culture conditions

Mice pretreated with Bacillus megaterium ATCC 33085 grown on TSA medium developed a significant increase in primary antibody response to SRBC. Conversely, pretreatment with a spore suspension harvested from nutrient Agar medium decreased this antibody response. A suspension of organisms grown on a defined, phosphorus-deficient medium (P-Medium) had no effect. Otherwise, only the spore suspension was able to enhance the contact sensitivity to dinitrofluorobenzene. Peritoneal leucocyte numbers were increased by inoculation with both TSA-cultured bacteria and the spore suspension, but not by P-Medium-cultured bacteria. Administration of both the spore suspension and P-Medium-cultured bacteria decreased the in vitro phagocytosis by peritoneal adherent cells. These immunomodulator properties are discussed in relation to characteristics of the strain tested.     

Imipenem/cilastatin therapy of infections in cancer patients

Imipenem/cilastatin was administered during 153 febrile episodes occurring in cancer patients and the response rate was 68%. Considering only documented infections the response rate was 71%. Patients who received imipenem as initial therapy had a higher response rate than patients who received it after failing other antibiotics (77% versus 68%). The overall response rates for septicemias and pneumonias were 75% and 58%. Among the 57 gram-negative infections 77% responded, but the response rate was substantially higher if imipenem was used as initial therapy (94% versus 69%). The poorest response rate was observed when imipenem was given as secondary therapy for Pseudomonas infections (50%), but most of these patients had failed to respond to other appropriate antibiotics. The only serious side effect was seizures which occurred in ten patients, although eight of them had other predisposing factors. Imipenem appears to be a useful antibiotic for treatment of infections, even in neutropenic cancer patients.     

Mycobacterium tuberculosis and Mycobacterium avium inhibit IFN- gamma -induced gene expression by TLR2-dependent and independent pathways.

Mycobacteria-infected macrophages are poor responders to interferon-gamma (IFN-gamma), resulting in decreased expression of IFN-gamma-induced genes. In the present study, we examined the inhibition of IFN-gamma-induced gene expression by Mycobacterium tuberculosis and four different Mycobacterium avium strains in mouse RAW264.7 macrophages. Gamma-irradiated M. tuberculosis inhibited mRNA expression of a panel of six different IFN- gamma-induced genes. All four of the M. avium strains completely inhibited IFN-gamma-induced expression of MHC class II Aalpha and Ebeta mRNA. However, the Mac101 strain, which is serovar 1, inhibited IFN-gamma induction of IFN regulatory factor-1 (IRF-1) and guanylate-binding protein-1 (GBP-1) mRNA to a greater extent than the other M. avium strains, which are serovar 2. In this study, we also show that mycobacteria inhibit gene expression by both toll-like receptor 2 (TLR2)-dependent and independent pathways. The inhibition of IFN-gamma-induced gene expression by M. avium was reduced but not completely blocked in macrophages from TLR2(/) mice. IFN-gamma-induced gene expression was also inhibited by mycobacteria in RAW264.7 cells expressing dominantnegative TLR2 or myeloid differentiation factor 88 (MyD88), further indicating the existence of a pathway independent of TLR2 and MyD88. These data suggest that mycobacteria inhibit IFN-gamma-induced gene expression by multiple pathways involving both TLR2 and non-TLR receptors.