Is Devic's neuromyelitis optica a separate disease? A comparative study with multiple sclerosis

Devic's neuromyelitis optica (NMO) associates optic neuritis and myelopathy without other neurological signs. Many patients with NMO may be diagnosed as having multiple sclerosis (MS). However, there have been no previous studies comparing these two pathologies and it is still unclear if NMO is a separate entity or a subtype of MS. In the present study, we compared a series of NMO patients with a series of MS patients for whom optic neuritis or myelopathy was the presenting symptom, in order to determine the place of NMO in the spectrum of MS. We retrospectively studied 30 patients diagnosed with NMO and we compared these patients with 50 consecutive MS cases revealed by optic neuritis or acute myelopathy. MS patients were only included if a relapse occurred demonstrating time and space dissemination. We compared the two groups in terms of clinical presentation, laboratory findings (MRI and CSF) and clinical outcome. NMO patients were older and more frequently women than MS patients but the difference was not significant. CSF and MRI data were clearly different: oligoclonal bands (OCB) were found in 23% of NMO cases and 88% of MS (P < 0.001), abnormal brain MRI data were observed in 10% of NMO cases and 66% of MS (P < 0.001) and a large spinal cord lesion was observed in 67% of NMO cases and 7.4% of MS cases (P < 0.001). Clinical outcome was evaluated as more severe in the NMO group (P < 0.001). On the basis of clinical data, all NMO patients but three had dissemination in time and space. When we included MRI parameters, only two of the NMO patients met criteria for MS and one of the MS patients met criteria for NMO. Our study demonstrates that NMO and MS should be considered as two different entities. The respective criteria for NMO and MS were able to distinguish these two pathologies but only when MRI data were applied. This finding could have implications for future therapeutic trials.     

Secretory characteristics and viability of human term placental tissue after overnight cold preservation

Collection of human term placentae for research purposes is generally limited during working hours. Preserving placental tissue overnight might help to postpone experiments and, by extent, to increase material availability. In this study, fragments from normal placentae were incubated at 37 degrees C either immediately after delivery or after preservation at 4 degrees C in a HEPES-buffered solution or in a Roswell Park Memorial Institute (RPMI) 1640 culture medium. Protein, human chorionic gonadotrophin (HCG), human placental lactogen (HPL) and lactate dehydrogenase (LDH) contents within preserved explants were similar to those within freshly delivered ones. In contrast, HCG and HPL amounts released during incubation of preserved tissue were lower than with freshly delivered tissue. Differences were significant only during the first 3 h of incubation. Hormone releases were similarly Ca(2+)-stimulated, and Co(2+)- and low temperature-inhibited in preserved and freshly delivered tissues. After preservation, LDH leakage was also reduced. Furthermore, before and after 37 degrees C incubation during 6 h, preserved tissue was morphologically indistinguishable from freshly delivered tissue and showed neither higher incidence of DNA fragmentation, nor elevated caspase-3 activity, both of which are markers of apoptosis. This study validates an original, useful and rapid method to preserve placental tissue. Consequently, this preservation model may facilitate the study of physiological processes regulating placental hormone secretion in normal and pathological conditions.     

An ERD mapping study of the neurocognitive processes involved in the perceptual and semantic analysis of environmental sounds and words

The aim of this paper was to investigate and compare the EEG mechanisms underlying the perceptual and semantic processes involved in environmental and language sounds perception by manipulating the degree of identification of sounds and using the ERD (event-related desynchronization) method in healthy subjects. Four types of stimuli were analyzed: meaningful environmental sounds, meaningless sounds, words and non-words. We report many similarities in the ERDs and ERSs (event-related synchronizations) patterns among all stimuli, with: (i) similar time-course of ERDs and ERSs between meaningful environmental sounds and words, and between meaningless sounds and non-words; (ii) similar topography of the maximal ERDs for meaningful environmental sounds, words and non-words; and (iii) same right posterior ERSs for all four stimuli. However, differences were also observed: (i) in time-course, with earlier ERSs for meaningless than meaningful stimuli, whether environmental or verbal; and (ii) in topography, with ERDs predominating in left and right hemisphere channels for meaningful and meaningless environmental sounds, respectively; (iii) ERSs predominating in the left temporal channel for non-words and in the left posterior and right frontal channels for meaningless sounds. The results of this study suggest that meaningful stimuli involve greater and longer-lasting semantic processes than meaningless stimuli, while the occurrence of ERSs for the latter points to the possible involvement of an inhibitory processing of semantic representations. Finally, the findings concerning the comparison between verbal and non verbal stimuli suggest the involvement of left-lateralized phonological and semantic processes for the former, and more distributed neurocognitive processes in both hemispheres for the latter although with predominant left laterality for their semantic processing.     

Advanced breast cancer: an evaluation of the cost of recurrence]

In the context of a medicoeconomic study of the adjuvant treatment of breast cancer, we evaluated the cost of the recurrence. This cost was assessed from the medical records of 146 patients having presented either distant metastases, or a local recurrence followed or not by metastases between 1983 and 1990. We checked according to published data that the frequency of the metastatic risk is negligible if beyond 5 years after the local recurrence. Costs are expressed in 1995 French Francs (FF), with the French Social Security point of view. From the medical records, we calculated the mean cost of each type of recurrence using medical costs (visits, drugs and treatments, assessments, tests, hospital care, outpatient services.) and non medical costs (patient transportation). The costs are 175,168 FF (standard deviation or SD: 127,972) for metastatic recurrence, and respectively 287,582 FF (SD: 142,280) and 115,705 FF (SD: 78,677) for local recurrence followed or not by metastases. There is a significant difference between these figures (p < 0.001). The hospitalization costs are around 66% of the total cost of each type of recurrences and they are significantly higher (p < 0.005) when metastatic disease occurs after a local recurrence. The mean cost of isolated local recurrence added to metastatic recurrence, 290,873 FF, is not different from that of local recurrence followed by metastases, 287,582 FF (p = 0.15). These results will be integrated in a model in order to evaluate the long-term economic consequences of an adjuvant strategy in the treatment of breast cancer and presented in other publications.     

Prolonged QT interval and cardiac arrhythmias in two neonates: sudden infant death syndrome in one case

Two neonates with arrhythmias and the long QT syndrome are described. The arrhythmias were detected in utero and both infants were apparently well after birth. The first infant, although well, had a bradycardia for the first 9 days of life. A normal heart rate was documented at 10 days but a prolonged QT interval was not appreciated on the ECG. He was discharged from hospital but died suddenly and unexpectedly 3 days later. A post-mortem examination failed to find a cause for his death which therefore fell into the category of the sudden infant death syndrome (SIDS). A retrospective analysis of the perinatal electrocardiogram showed a probable junctional rhythm with 2:1 conduction to the ventricle; the QT interval was prolonged at 0.52 seconds (QTC = 0.63). The second infant had a QT interval of 0.52 seconds (QTC = 0.54) and frequent ventricular premature beats on a 24-hour electrocardiogram. She was treated with propranolol and remains well 2 years later. Sudden infant death has often been described in the siblings of children with the long QT syndrome and one other report described a case of SIDS which was said to have had a prolonged QT interval on the perinatal ECG. This report, however, provides unquestionable evidence, in one case, of an association between the long QT syndrome and SIDS.     

Excretory urography with iohexol: evaluation in children

A multicenter clinical study was conducted using iohexol, a second-generation nonionic contrast medium, for excretory urography performed in 130 children. Doses of iohexol (300 mg iodine/ml) ranged between 150 and 660 mgI/kg (0.5 and 2.2 ml/kg). Iohexol was tolerated well, and no significant adverse reactions occurred. Sixty-five iohexol urograms were evaluated to determine the minimum dose for adequate visualization of the kidneys and collecting systems. A dose greater than 300 mgI/kg (1.0 ml/kg) always resulted in a urogram of diagnostic quality, while visualization was insufficient for diagnosis in 10% of studies done with doses of 150-300 mgI/kg (0.5-1.0 ml/kg). Another 65 iohexol urograms were compared in a blinded manner with a similar number of studies performed using iothalamate meglumine at comparable iodine concentration and dose. Visualization of calyces and pelvoinfundibular structures achieved with iohexol was rated better with statistical significance, but there was no difference in visualization of the renal parenchyma or ureters. Use of iohexol in excretory urography may be advantageous in children who are at greatest risk for an adverse reaction to contrast media or in those most likely to benefit from use of a low osmolality contrast agent.     

Volumetric rendering techniques: applications for three-dimensional imaging of the hip

Volumetric rendering is a new approach to three-dimensional (3D) imaging that overcomes many of the drawbacks of currently available surface-rendering systems. Its application on the Pixar Imaging System in two cases of acetabular fracture was assessed to illustrate the features of the technique. The fast-computing architecture and large memory of this system allow rapid generation of a series of high-quality 3D images in each plane of rotation (x or spinal axis, z or somersaulting axis) that can be viewed as independent static images or as an animated real-time video loop. Editing to remove the normal contralateral hemipelvis enhances appreciation of acetabular abnormalities. Every pixel of computed tomographic data is preserved, allowing representation of both soft tissue and bone as translucent overlap. The presentation of data also allows detection of subtle abnormalities and features and minimizes the artifact generation common in surface-rendered images.     

Diagnostic value of thallium 201 scintigraphy in the determination of malignancy of cold thyroid nodules

In this paper we discuss and quantify the respective values of Thallium 201 scintigraphy and cytologic punction in determining malignancy of the cold thyroid nodule. These two diagnostic tests are evaluated on the basis of their sensitivity and specificity while taking into consideration various therapeutic attitudes in the presence of a cold thyroid nodule.