Gaucher disease: assessment with MR imaging

The skeletal system, spleen, and liver of five patients with proved Gaucher disease were studied with magnetic resonance (MR) imaging. Homogeneous, low intensity signals resulting from relaxation times different than normal (longer T1 and shorter T2 values) were found in the marrow of long bones, vertebrae, and hips in all patients. In three patients, normal signals were noted in the patella, epiphysis of the knee, and capital femoral epiphysis. In two patients with acute bone pain in the tibial region, a higher signal was received from the tibial marrow. This signal was related to increased accumulation of fluid following an avascular episode. Soft tissues in the same area were also involved. Liver and spleen enlargement was readily visible, especially on coronal images. T1 values of spleen were significantly shorter than normal. MR imaging provides an excellent assessment of the extent of involvement of the liver, spleen, and bone marrow in Gaucher disease.     

Perinatal outcome of ICSI pregnancies compared with a matched group of natural conception pregnancies in Flanders (Belgium): a cohort study

A retrospective cohort study was conducted with an intracytoplasmic sperm injection (ICSI) group and a naturally conceived comparison group. A total of 1655 singleton and 1102 twin ICSI births were studied with regard to perinatal outcome. Control subjects (naturally conceived pregnancies) were selected from a regional registry and were matched for maternal age, parity, place of delivery, year of birth and fetal sex. The main outcome measures were duration of pregnancy, birth weight, Apgar score <5 after 5 min, neonatal complications, perinatal death and congenital malformations. Twin births, when compared with singletons, carry a much higher risk of poor perinatal outcome. For both ICSI singletons and ICSI twins, no significant difference was found between ICSI and naturally conceived pregnancies for all investigated parameters. After excluding like-sex twin pairs, ICSI twin pregnancies were at increased risk for perinatal mortality (OR = 2.74, CI = 1.26-5.98), prematurity (OR = 1.38, CI = 1.10-1.75) and low birth weight (OR = 1.34, CI = 1.06-1.69) compared with spontaneously conceived different-sex twin pairs. In conclusion, the perinatal outcome of ICSI singleton and twin pregnancies was very similar to that of spontaneously conceived pregnancies in this large cohort study. After excluding like-sex twin pairs, ICSI twins were at increased risk for prematurity, low birth weight and higher perinatal mortality compared with the natural conception comparison group.     

Multifocal electroretinograms combined with periodic flashes: direct responses and induced components

Purpose To investigate the retinal responses generated by flash interactions in a recently introduced global (full-screen) flash stimulus paradigm to record the multifocal electroretinogram (mfERG).Methods Five normal individuals were studied with stimulation combining multifocal (pseudorandom) flashes with interleaved global (periodic, full-screen) flashes. The intensities of the two flashes were independently varied. Two distinct first-order response components were obtained: the mean response to the focal flashes (referred to as the direct response, DR) and the effect of the focal flash on the responses evoked by the global flash (the induced component, IC).Results Increasing the global flash luminance reduced DR amplitude and shortened DR implicit time. IC amplitude peaked with a moderate global flash (1.33–2.67 cd·s/m²). With a global flash of the right intensity, a weak focal flash could evoke a considerable IC even when the DR was barely detectable. Moderate global flashes maximized the IC, and its intersubject variability was reduced at lower focal flash luminances. IC topography had a large naso-temporal asymmetry.Conclusions While the DR is the average response generated by the local flashes regardless of the context of preceding and following flashes, the IC represents the difference in the global flash response in the presence and absence of the preceding focal flash. As the focal flashes were always preceded by the periodically occurring global flashes, the DR reflects the resulting adapted or desensitized state of the retinal patch. The pure, nonlinear IC is thought to reflect predominantly inner retinal function.     

Screening test battery for pharmaceuticals in urine and wastewater

A test battery for identifying ecotoxicological hazards was applied to six pharmaceuticals (carbamazepine, diclofenac, ethinylestradiol, ibuprofen, propranolol, and sulfamethoxazole), to their mixtures, and to urine spiked with pharmaceuticals to test the suitability of biotests for screening urine and wastewater and for monitoring the efficiency of wastewater treatment. The test battery comprised the bioluminescence inhibition test with Vibrio fischeri, the yeast estrogen screen, and a photosynthesis inhibition assay in algae based on chlorophyll fluorescence measurements. Mixture and additional experiments with a cocktail of pharmaceuticals added to urine confirmed the applicability of the test systems as an integrated measure of the overall micropollutant burden. Because the concentration of pharmaceuticals in wastewater is low and the nutrients and salts may have a negative impact on the bioassays, urine and wastewater samples were cleaned and concentrated by solid-phase extraction (SPE). The compounds of interest ranged from polar to nonpolar and from positively charged to neutral and negatively charged. Consequently, the SPE method was optimized for universality rather than for specificity. Results of preliminary experiments with raw and treated urine and wastewater indicate the suitability of the proposed test battery for screening urine and wastewater.     

Comparison of the hepatic mixed function oxidase system of young, adult, and old non-human primates (Macaca nemestrina)

The influence of age on the mixed function oxidase system from a non-human primate was studied. Microsomes were isolated from the livers of female Macaca nemestrina ranging from 2 to 21 years of age. No significant age-related change was observed in either the cytochrome P-450 content or the NADPH cytochrome c reductase activity. In addition, the ability of the microsomes to metabolize benzo [a]pyrene did not change significantly with age. These observations contradict studies with liver tissue from laboratory rodents in which an age-related decline in the mixed function oxidase system is generally observed. The lipid composition of the liver microsomes was studied also. Both the cholesterol and total phospholipid content of the liver microsomes increased significantly with age; however, the ratio of cholesterol to phospholipid remained constant. The percentage of individual phospholipids in the microsomes changed only slightly with age. These results provide new information on the effect of age on the mixed function oxidase system and indicate that one must be cautious in extrapolating from studies with liver tissue from laboratory rodents to primates.     

Study of serum factors potentially involved in the pathogenesis of heterotopic bone formation after severe brain injury

OBJECTIVE: To look for serum factors detectable early after head injury and predictive of heterotopic bone formation. PATIENTS AND METHODS: In this prospective study of a homogeneous population of 31 men with severe brain injury, blood samples were obtained 3 months after the accident, and levels of serum factors influenced by bone metabolism were compared between patients with and without heterotopic bone formation. As extensive fractures can influence serum factors, the patients without heterotopic bone formation were divided into two groups based on whether they had major fractures. Radionuclide bone scanning was used to validate patient classification. RESULTS: The group with heterotopic bone formation had significantly higher serum alkaline phosphatase levels (P < 0.01) and significantly lower serum leptin levels (P < 0.01), as compared to the other two groups. Body mass index and serum creatinine were comparable in the three groups. CONCLUSION: Leptin may be associated with the development of heterotopic bone formation. The antiosteogenic effect of leptin mediated by hypothalamic neurons may be impaired by hypothalamic damage related to severe brain injury.