Atypical presentation of NREM arousal parasomnia with repetitive episodes

The case report describes a distinct variant of non-REM (Rapid Eye Movement) arousal parasomnia, sleepwalking type, featuring repetitive abrupt arousals, mostly from slow-wave sleep, and various automatisms and semi-purposeful behaviours. The frequency of events and distribution throughout the night presented as a continuous status of parasomnia (' status parasomnicus '). The patient responded well to treatment typically administered for adult NREM parasomnias, and after careful review of the clinical presentation, objective findings and treatment outcome, sleep-related epilepsy was ruled out in favour of parasomnia.     

Dysembryoplastic neuroepithelial tumor in the left lateral ventricle.

Extracortical location of dysembryoplastic neuroepithelial tumor (DNT) is rare. We present a case of DNT localized in the left lateral ventricle of a 21-year-old female patient. Magnetic resonance imaging of the brain showed a round mass lesion in the floor of the anterior horn of the left lateral ventricle. The lesion was hypointense on T (1)-weighted images and slightly hyperintense on T (2)-weighted images without contrast enhancement. Total removal of the yellowish-white colored soft tumor was performed through a transcallosal approach. Histologically, the tumor was of simple type of DNT that was composed of small oligodendrogliocytes clustered tightly about perivascular spaces with neurons floating in mucoid pools showing an eosinophilic fibrillary matrix in the background. The recognition of DNT with an unusual location in lateral ventricle has therapeutic and prognostic significance since DNT is curable by surgical excision and radiation therapy is of no obvious benefit.     

Cyclophosphamide-induced cytogenetic effects in mouse bone marrow and spleen cells in in vivo and in vivo/in vitro assays

Sister chromatid exchange (SCE) and chromosomal aberration studies have been used to monitor human populations for genotoxic exposure to chemical substances. These monitoring techniques involve collection of blood and/or bone marrow from the exposed subjects and culturing cells for one or two cell cycles with various treatments in culture. The results obtained from such in vivo/in vitro studies may lead to an over- or underestimation of the damage that could occur in vivo. In the present study, which uses a mouse model, the in vivo/in vitro cytogenetic assays (SCEs and chromosomal aberrations) have been compared with similar in vivo systems in bone marrow and spleen cells treated with various doses of cyclophosphamide (CPA). The results indicate a significant difference in CPA-induced cytogenetic endpoints between in vivo and in vivo/in vitro conditions in both organs. However, linear relationships were found between CPA dose and cytogenetic end point analyzed under both conditions. Based on these results it appears that the in vivo/in vitro assay is a useful technique for indicating potential in vivo damage of chemicals.     

Polysialic acid, a unique glycan that is developmentally regulated by two polysialyltransferases, PST and STX, in the central nervous system: From biosynthesis to function

Polysialic acid is a developmentally regulated carbohydrate composed of a linear homopolymer of a-2,a-linked sialic acid residues. This unique glycan is mainly attached to the neural cell adhesion molecule (N-CAM) and implicated in many morphogenic events of the neural cells by modulating the adhesive property of N-CAM. Recently, the cDNA that encodes polysialyltransferase, which is responsible for the polysialylation of N-CAM, was successfully cloned from three mammalian species. This review focuses on the molecular cloning of human polysialyltransferase, designated PST. it then describes the number of enzymes actually required for the polysialylation of N-CAM using an in vitro polysialyltransferase assay. Comparisons between PST and another polysialyltransferase, sialyltransferase X (STX), are made and it Is demonstrated that both enzymes can independently form polysiatic acid In vitro , but that during neural development they coordinately but distinctly synthesize polysialic acid on N-CAM. The role of polysialic acid in the central nervous system is also discussed. Finally, evidence that the two polysialyltransferases, PST and STX, apparently have distinct roles in the development of neural cells is provided by using a neurite outgrowth assay.     

Relative carriage rates of nuclear dehydrogenating clostridia in two populations of different colorectal cancer risk

Carriage of nuclear dehydrogenating clostridia has been associated with colon cancer and implicated in its aetiology. This study has compared the carriage of these organisms in a British population at high risk for the development of colon cancer with a low risk Nigerian population. Clostridia were found in all of the stools from both populations. Nuclear dehydrogenating clostridia were only found in the stools of the British subjects (32%). These results support the suggestion that the carriage rate of nuclear dehydrogenating clostridia in a population is related to the risk of colon cancer.     

Plasmodium falciparum sexual stage antigens: immunogenicity and cell-mediated responses.

Antibody and cell-mediated immune responses to the transmission-blocking target antigens of Plasmodium falciparum, Pfs 48/45, were determined in infected non-immune patients and in immune individuals from an endemic area. Characterization of the B cell epitopes with monoclonal antibodies showed that there were five regions identifiable but there could be interactions between them causing either competitive or enhancing effects. Sera from infected non-immune patients contained antibodies that would compete with one or more of the mAbs to the different epitopes. Immune responsiveness to purified Pfs 48/45 in P. falciparum-immune adults measured as lymphoproliferation, production of interferon-gamma, or as Pfs 48/45-specific antibody was very limited. This did not appear to be due to MHC class II restriction, to diversity in structure of the parasite antigens or to a failure of immunological memory. The antibody-response data were more consistent with down-regulation of immunity as a result of prolonged exposure to infection.     

Development of hatching blastocysts from immature human oocytes following in-vitro maturation and fertilization using a co-culture system

Recently, in-vitro maturation (IVM) of immature human oocytes recovered from non-stimulated follicles has been applied in the treatment of infertility. However, in previous reports, very few embryos cultured in conventional medium have reached the expanded blastocyst stage following in-vitro maturation and fertilization (IVM/IVF). The objective of this study was to investigate whether the developmental competence of human embryos following IVM/IVF could be enhanced by the use of a human ampullary cell co-culture system. Immature human oocytes were aspirated from small follicles at Caesarean section and then cultured in medium containing human menopausal gonadotrophin for 36 to 48 h, followed by insemination. Zygotes were randomly cultured either in conventional culture medium alone or in the co-culture system. Of 48 embryos cultured in conventional medium alone, all arrested at the 2-16- cell stage on day 3 after insemination. Of 46 embryos cultured in the co-culture system, 26 embryos (56.5%) arrested at the 2-16-cell stage. Six embryos (13%) developed to the morula stage. Fourteen embryos (30.4%) developed to expanded blastocysts and two blastocysts were hatching on day 7 after insemination. We conclude that co-culture significantly enhances the development of blastocysts in embryos resulting from IVM/IVF.      

Evaluation of the common conditions associated with eosinophilia.

In an eosinophilic population of 47 boys of the same age, a large proportion (92%) were helminth infested or atopic, or both, compared with 36% of 36 controls. The methods used to detect these conditions were not costly or elaborate, except for the radioallergosorbent test, which was used to measure concentrations of circulating IgE antibodies to atopic allergens. It is suggested that an economical approach to detect helminthiasis and atopy in cases of eosinophilia is adopted using the methods employed here, with skin prick tests replacing the radioallergosorbent test.     

Sliding window dual gradient echo (SW-dGRE): T1 and proton resonance frequency (PRF) calibration for temperature imaging in polyacrylamide gel

The aim of the work is to evaluate a magnetic resonance imaging (MRI) thermometry sequence suitable for targeting of focused ultrasound (FUS) when used in vascular occlusion studies. A sliding window dual gradient echo (SW-dGRE) sequence was used. This sequence has the capability of monitoring both T1 relaxation and phase changes, which vary with temperature. Preliminary work involved quantification of the changes in T1 relaxation time with temperature and obtaining the PRF shift coefficient in polyacrylamide gel as it underwent an exothermic reaction during polymerization (avoiding the use of an external heat source). Temperature changes were visualized using thermal maps acquired with the sequence. For FUS guidance a thermal imaging technique is required with a temporal resolution <5 s, a spatial resolution of approximately 1 mm and a temperature resolution of approximately 5 degrees C. The sequence was optimized to improve the CNR (contrast to noise ratio) and SNR (signal to noise ratio) in the phase and magnitude images respectively. The PRF coefficient obtained for the polyacrylamide gel was -9.98 +/- 0.24 ppb degrees C(-1), whilst deltaT1 and temperature change were related by a proportionality factor, the T1 temperature coefficient, of 102.3 +/- 2.9 ms degrees C(-1). The sequence produces an image at every 1.4 s interval. In both magnitude and phase data, the in-plane resolution is +/- 1.2 mm and the temperature resolution is approximately 2 degrees C. The advantage of this sequence is that the temperature obtained from the magnitude data can be confirmed independently using the phase data and vice versa. Thus the sequence can essentially be crosschecked.