Real-time evaluation of the effectiveness of microwave coagulation therapy for hepatocellular carcinoma using color Doppler imaging

Percutaneous microwave coagulation therapy (PMCT) is a new technique for the treatment of hepatocellular carcinoma (HCC). However, it is difficult to distinguish those lesions in which necrosis has been induced from the viable residual lesions during the procedure, because the margin of the tumor becomes unclear during PMCT. We determined the area of necrotic lesions during the procedure using color Doppler imaging. PMCT was performed on 10 patients (17 lesions) with recurrent HCC. The electrode of the microwave delivery system was moved around the tumor and the surrounding area until color mosaic images disappeared from the entire area of the tumor. The areas in which necrotic tissue was indicated by color Doppler imaging were later confirmed by other modalities such as angiography or contrast-enhanced computed tomography. This leads us to believe that real-time, effective evaluation of PMCT is possible with color Doppler imaging.

Age-related changes in aortic sensitivity to noradrenaline and acetylcholine in rats

1. The purpose of the present study was to determine the relationship between plasma and tissue lipid levels and the effects of age on vascular responses to noradrenaline (NA) and acetylcholine (ACh). 2. Studies were performed in young and aged rats and the response of endothelium-intact and -denuded aortic rings to NA and to ACh was measured. The plasma concentration of cholesterol (total, high-density lipoprotein (HDL) and low-density lipoprotein (LDL)) and 17 beta-oestradiol was determined, as was the aortic tissue content of phospholipids, cGMP and cholesterol (total, free and esterified). 3. Levels of all types of cholesterol in plasma and aorta increased with age; cholesterol levels in plasma correlated with those in the aorta; levels of phospholipid in the aorta did not increase with age but correlated with those of LDL cholesterol in plasma; levels of 17 beta-oestradiol did not change, but those of cGMP increased with age. 4. In endothelium-intact rings, the maximum tension developed by exposure to NA did not change, but the EC50 of NA increased with age and correlated with total cholesterol in the plasma and with the levels of all types of cholesterol in the aorta. In rings precontracted with NA, age decreased the maximum relaxation induced by ACh. The EC50 of ACh decreased with age and was inversely correlated with levels of cholesterol in the plasma and aorta. Treatment with NA increased cGMP levels in aged rats. Removal of the endothelium abolished the response to ACh and heightened the sensitivity to NA in young and aged rats. 5. Aortic endothelial cells seem to inhibit amine-induced contraction, while age-related changes in the levels of cholesterol in aortic tissue affect the sensitivity of the tissue to NA and ACh.

Tectal projections to the parvicellular reticular formation and the upper cervical spinal cord in the rat, with special reference to axon collateral innervation

After Phaseolus vulgaris leucoagglutinin injection into the lateral part of the superior colliculus (SC) in the rat, labeled fibers and axon terminals in the lower brainstem were distributed not only in the medial reticular formation but also in the lateral tegmental field including the parvicellular reticular formation (RFp). More caudally, in the upper cervical spinal cord labeled fibers with bouton-like varicosities were distributed mainly in laminae V, VII and VIII, with relatively sparse distribution in lamina IX. These labeled axons were found bilaterally with a clear-cut contralateral dominance. After combined injections of rhodamine-dextranamine, Fluoro-ruby (FR) into the RFp and Fluoro-gold (FG) into the upper cervical spinal cord on the same side, SC neurons labeled with FR were intermingled with those labeled with FG in the lateral part of the SC contralateral to the injection sites. In the stratum griseum intermediale, some of them were double-labeled with both tracers. Our results suggest that SC neurons innervating both the RFp and the cervical spinal cord may be involved in the coordination of head and mouth movements.

Developmental appearance of oligodendrocytes in the embryonic chick retina

The axons of the optic nerve layer are known to be myelinated by oligodendrocytes in the chick retina. The development of the retinal oligodendrocytes has been studied immunohistochemically with antibodies against oligodendrocyte lineage: monoclonal antibodies O4 and O1, and an antibody against myelin basic protein. O4 positive (O4+) cells were first detected in the retina on the tenth day of incubation (embryonic day (E)10, stage 36). The labeled cells were located in the optic nerve layer close to the optic fissure. Most were unipolar in shape, extending a leading process with a growth cone toward the periphery of the retina. By E12, unipolar O4+ cells had spread to the middle of the retina. Many O4+ cells close to the optic fissure showed radial arrangement with extension of processes toward the inner limiting membrane. O1+ oligodendrocytes were first observed in the E14 retina positioned just above (interiorly to) retinal ganglion cells. These labeled cells extended fine processes in the optic nerve layer. Limited numbers of myelin basic protein-positive cells were present by E16 and located interiorly to the retinal ganglion cells. In addition to the oligodendrocyte in the optic nerve layer, a limited number of O4+ cells were observed in the inner nuclear layer by E14, and they became O1+ by E18. Furthermore, explant culture experiments showed E10 to be the youngest stage at which the retina contained oligodendrocyte precursors. An intraventricular inj ection of fluorescent dye 1,1',dioctadecyl-3,3,3',3-tetramethylindocarbocyanine perchlorate (DiI) at E6 yielded O4+/DiI+ cells in the retina at E10, which provided direct evidence to support migration of oligodendrocyte precursor into the retina. The present results demonstrated the sequential appearance of the cells of oligodendrocyte lineage and the detailed morphology of the developing oligodendrocytes in the retina. These morphologic features strongly suggested that retinal oligodendrocytes were derived from the optic nerve and spread by migration through the optic nerve layer.

Phylogenetic relationships among Fagopyrum species revealed by the nucleotide sequences of the ITS region of the nuclear rRNA gene

The DNA sequences of the internal transcribed spacer (ITS) region of the rRNA gene were determined in 20 taxa of 12 species of Fagopyrum. By comparing the sequence data and constructing phylogenetic trees, the phylogenetic relationships among the Fagopyrum species were established. The sequences of ITS (ITS1 and ITS2) were about 3-7 times more variable than those of the 5.8S subunit of the rRNA gene. The classification of Fagopyrum species based on the DNA sequences of the rRNA gene almost coincides with the classification based on morphology, allozyme variability, and nucleotide sequences of the rbcL-accD region of the chloroplast DNA. A close relationship of F. lineare with the F. statice-F. leptopodum clade was suggested and this was strongly supported by a 68-bp gap in ITS1 found in these three species. A tetraploid F. cymosum from Kathi, India, has two distinct rRNA genes probably on homoeologous chromosomes, and was distinguished from the clade of other diploid/tetraploid F. cymosum with a high bootstrap value. This strengthened the hypothesis of the polyphyletic origin of the tetraploid F. cymosum.

Interspecific relationships in Fagopyrum (Polygonaceae) revealed by the nucleotide sequences of the rbcL and accD genes and their intergenic region

DNA sequences of the rbcL and accD 5' coding regions and their intergenic region (IGR) were determined in 20 taxa of 12 species of Fagopyrum. By comparing the sequence data and constructing phylogenetic trees, phylogenetic relationships among Fagopyrum species were investigated. The accD 5' coding region and the IGR have evolved about five times faster than the rcbL coding region; hence the phylogenetic trees based on the data of the accD 5' coding region, the IGR, and these data combined, had higher resolution than the trees based on rcbL alone. The classification of Fagopyrum based on the DNA sequences was almost perfectly consistent with the classification by Ohnishi and Matsuoka (1996, Genes & Genetic Systems 71: 383-390). New facts and minor differences are (1) polyploidization in F. cymosum might have occurred more than once, (2) F. lineare may not be a sister species of F. leptopodum, and (3) F. pleioramosum rather than F. capillatum may be a sister species of F. gracilipes.

Variation in mammographic breast density by time in menstrual cycle among women aged 40-49 years

BACKGROUND

Mammography is less effective for women aged 40-49 years than for older women, which has led to a call for research to improve the performance of screening mammography for younger women. One factor that may influence the performance of mammography is breast density. Younger women have greater mammographic breast density on average, and increased breast density increases the likelihood of false-negative and false-positive mammograms. We investigated whether breast density varies according to time in a woman's menstrual cycle.

METHODS

Premenopausal women aged 40-49 years who were not on exogenous hormones and who had a screening mammogram at a large health maintenance organization during 1996 were studied (n = 2591). Time in the menstrual cycle was based on the woman's self-reported last menstrual bleeding and usual cycle length.

RESULTS

A smaller proportion of women had "extremely dense" breasts during the follicular phase of their menstrual cycle (24% for week 1 and 23% for week 2) than during the luteal phase (28% for both weeks 3 and 4) (two-sided P = .04 for the difference in breast density between the phases, adjusted for body mass index). The relationship was stronger for women whose body mass index was less than or equal to the median (two-sided P<.01), the group who have the greatest breast density.

CONCLUSIONS/IMPLICATIONS

These findings are consistent with previous evidence suggesting that scheduling a woman's mammogram during the follicular phase (first and second week) of her menstrual cycle instead of during the luteal phase (third and fourth week) may improve the accuracy of mammography for premenopausal women in their forties. Breast tissue is less radiographically dense in the follicular phase than in the luteal phase.

Isolation, purification, and characterization of a collagen-associated serpin, caspin, produced by murine colon adenocarcinoma cells

A 45-kDa serpin secreted by a murine colon adenocarcinoma cell line, colon26, was isolated, purified, and characterized. It was found to bind specifically to type I collagen with high affinity and to type III collagen with lower affinity. Immunohistochemical studies of murine embryonic tissues showed a specific distribution of this collagen-associated serpin, named caspin, in relation to the formation of bone, cartilage, teeth, and basement membrane. The expression of caspin in high and low lung metastatic subclones of colon26 cell lines was inversely correlated with their metastatic capacity: low lung metastatic cells secreted higher amounts of caspin than their high lung metastatic counterparts. Caspin also demonstrated high homology with human pigment epithelium-derived factor/early population doubling level cDNA-1, which reportedly induces neuronal differentiation of human retinoblastoma cells and is expressed in association with G0 growth arrest. These findings suggest that caspin/pigment epithelium-derived factor/early population doubling level cDNA-1 is a novel factor that might play a crucial role in embryogenesis and tumor metastasis through binding to the extracellular matrix.

Patient empowerment and feedback did not decrease pain in seriously ill hospitalized adults

We tested a nurse clinician-mediated intervention to relieve pain in a group of seriously ill hospitalized adults using a randomized controlled trial at five tertiary care academic centers in the US. The study included 4804 patients admitted between January 1992 and January 1994 with one or more of nine high mortality diagnoses; 2652 were allocated to the intervention and 2152 to usual care. Specially-trained nurse clinicians assessed patients' pain, educated them and their families about pain control, empowered patients to expect pain relief, informed patients' nurses and physicians about level of pain and suggested or used other pain management resources. Patients' pain was determined from hospital interviews with patients and surrogates. Pain 2 and 6 months later or after death and satisfaction with its control at all time periods were also assessed. All analyses were adjusted for baseline risk of being in pain and propensity to be in the intervention group. Overall, 50.9% of patients reported some pain. After adjustment for other variables associated with pain, comparing the intervention to the control group, there was not a statistically significant difference in level of pain (OR for higher levels of pain 1.15; CI 1.00-1.32) or satisfaction with control of pain during the hospitalization (OR for higher levels of pain 1.12; CI 0.91-1.39), 2 or 6 months after discharge, or during the last 3 days of life. A multifaceted intervention using information, empowerment, advocacy, counseling and feedback was ineffective in ameliorating pain in seriously ill patients. Control of pain in these patients remains an important problem. More intensive pain treatment strategies addressing the needs of seriously ill hospitalized adults must be evaluated.

Nigral axon terminals are in contact with parvicellular reticular neurons which project to the motor trigeminal nucleus in the rat

We examined whether in the rat the descending fibers from the substantia nigra pars reticulata (SNr) were in contact with premotor neurons projecting to the motor trigeminal nucleus (Vm), using a combined anterograde and retrograde tracing technique. After ipsilateral injections of cholera toxin B subunit (CTb) into the Vm and biotinylated dextranamine (BDA) into the SNr, numerous CTb-labeled neurons were distributed bilaterally with slightly ipsilateral dominance in the parvicellular reticular formation (RFp), where many BDA-labeled axons with bouton-like varicosities were found bilaterally with a clear-cut ipsilateral dominance. The overlapping distribution of these labeled axons and neurons was more prominent in the rostral RFp than in the caudal RFp. Within the neuropil of the RFp, some of the BDA-labeled axons made synapses with the somata and proximal dendrites of CTb-labeled neurons. Thus, the present study demonstrated the existence of an indirect pathway from the SNr to the Vm, relayed by the RFp.

Filopodia and growth cones in the vertically migrating granule cells of the postnatal mouse cerebellum

The details of the morphology of vertically migrating granule cells were examined semiquantitatively in the postnatal mouse cerebellum by a Golgi method, with special reference to the growth cone-related structures such as filopodia and lamellipodia. The first sign of inward migration was extension of short, vertical filopodium-like processes from the sides of the perikarya of tangentially oriented granule cells, followed by a change of orientation of cell bodies to the vertical axis showing a T-shaped morphology. The T-shaped migratory cells formed sprouted filopodia (side spikes) from their vertical leading processes and perikarya at right angles to the vertical axis. More than three-quarters of the migratory cells extended the side spikes. The presence of such side spikes was confirmed with laser scanning confocal microscopy of granule cells labeled with 1,1', dioctadecyl-3,3,3',3-tetramethylindocarbocyanine perchlorate and also with transmission electron microscopy (TEM). In addition, about one-fourth of migratory cells extended lamellipodia of web-like forms along the stem or at the tip of the leading process, some of which showed a typical growth cone. Several morphological variations of vertical granule cells were also observed. Furthermore, TEM observation confirmed that side spikes from migratory cells made direct contact with parallel fibers. The present results suggest that, during vertical migration, growth cone-related structures of the leading processes of granule cells adhere to and probably recognize tangentially oriented parallel fibers. Therefore, the mechanisms of the vertical guidance and migration of granule cells in the cerebellar cortex seem to be multiple, involving not only parallel contact guidance by the Bergmann glia fibers but also perpendicular contact guidance by the parallel fibers. These parallel and perpendicular geometric cues surrounding the granule cells seem to have produced the varying morphology of vertically migrating granule cells.

Evaluation of the AMPLICOR CMV test for direct detection of cytomegalovirus in plasma specimens

We evaluated the AMPLICOR CMV test (PCR) for the direct detection of cytomegalovirus in plasma. Sixty-eight specimens were involved for the comparison between the AMPLICOR test and the antigenemia assay. The sensitivities, specificities, and positive and negative predictive values were 97.1, 100, 100, and 97.1%, respectively, for the AMPLICOR test and 79.4, 100, 100, and 82.9%, respectively, for the antigenemia assay.

Enhancement of neurite outgrowth by the soluble form of human L1 (neural cell adhesion molecule)

L1, a neural cell adhesion molecule, is involved in neurite outgrowth, migration and fasciculation. Although L1 is a membrane glycoprotein expressed on neural cells, the soluble form of L1 is generated in vivo by proteolysis. In the present study, a stable transfectant of Chinese hamster ovary (CHO) cells secreting human L1 without cytoplasmic and membrane spanning domains was generated, and the function of the secreted L1 was examined. Explants from embryonic chick brain stem were cultured on a substrate coated with polyethylenimine (PEI) alone, on substrate-bound L1 or in medium containing soluble L1. The neurites induced by L1, both the substrate-bound form and the soluble form, were 2-3 times longer than those cultured on PEI. The ability of the soluble L1 to induce neurite formation was slightly greater than that of the substrate L1. The present results demonstrated that neurite outgrowth was induced not only by substrate-bound L1 but also by soluble L1. Soluble L1 could be a pharmaceutical candidate for the promotion of nerve regeneration.

Organization of the nigro-tecto-bulbar pathway to the parvicellular reticular formation: a light- and electron-microscopic study in the rat

We examined a nigro-tecto-bulbar pathway to the parvicellular reticular formation (RFp), where many premotor neurons for orofacial motor nuclei are known to be distributed, by using a combined anterograde and retrograde tracing method. After contralateral injections of biotinylated dextranamine (BDA) into the dorsolateral part of the substantia nigra (SNr) and cholera toxin B subunit (CTb) into the RFp, overlapping distributions of BDA-labeled terminals and CTb-labeled neuronal cell bodies were found in the lateralmost part of the superior colliculus (SC) ipsilateral or contralateral to the site of BDA injection or CTb injection, respectively. After contralateral injections of BDA into the SNr and horseradish peroxidase conjugated to wheat germ agglutinin (WGA-HRP) injection into the RFp, ipsilateral labeled axon terminals with BDA were found to make symmetrical synaptic contacts with the somata and dendrites of contralateral labeled neurons with WGA-HRP in the lateralmost part of the SC. Furthermore, we demonstrated that BDA-labeled axon terminals were immunoreactive for GABA, by using the anterograde tracing method combined with immunohistochemistry for GABA. Thus, GABA-like immunoreactive fibers originating from the dorsolateral part of the SNr make monosynaptic contacts with the tectal neurons sending their axons to the RFp.

Focal ventricular origin and migration of oligodendrocyte precursors into the chick optic nerve

During central nervous system (CNS) development, oligodendrocyte precursors originate in specific locations and subsequently migrate to all regions of the CNS. Here, we demonstrate that the chick optic nerve is populated by oligodendrocyte precursors, which initially appeared in a focal region at the ventral midline of the third ventricle at stage 26-27. Oligodendrocyte precursors migrated into the chiasmal end of the nerve by stage 29 and became uniformly distributed by stage 35. Migrating precursors were restricted to the anterior region of the nerve, closely apposed to axons, and had a bipolar morphology. In contrast to the polysialic acid (PSA)-dependent cooperative streaming migration of olfactory neuronal precursors, the migration of oligodendrocyte precursors along the optic nerve appeared axophilic and unaffected by removal of neural cell adhesion molecule (N-CAM)-associated PSA. These data indicate that during development, defined domains of the ventricular zone give rise to distinct cell types that utilize discrete mechanisms to navigate specific migrational pathways.

Immunohistochemical differentiation of fiber types in human skeletal muscle using monoclonal antibodies to slow and fast isoforms of troponin I subunit

The cDNA sequence of troponin I (TnI), one of the subunits of the skeletal muscle regulatory protein, differs between slow-twitch muscle and fast-twitch muscle. We prepared monoclonal antibodies to the slow and fast isoforms of human TnI for the purpose of differentiating muscle fiber types in human neuromuscular disorders. Slow TnI antibody was labeled with tetramethylrhodamine isothiocyanate while fast TnI antibody was labeled with fluorescein isothiocyanate; then these two antibodies were mixed. This mixture was then used to stain biopsied muscle from patients with neuromuscular disorders. It was possible to differentiate muscle fibers into slow, fast and intermediate fibers having various contents of slow and fast TnI. In tissue composed of small muscle fibers, this method facilitated differentiation of types of muscle fibers by allowing staining of only a single section. The usefulness of our technique using slow and fast TnI antibodies is discussed in comparison with ATPase staining. Because our staining method can distinguish slow and fast fiber components, it is useful for clinical application.

Adult respiratory distress syndrome, pneumonia, and mortality following thoracic injury and a femoral fracture treated either with intramedullary nailing with reaming or with a plate. A comparative study

Multiply injured patients (an Injury Severity Score of 17 points or more) who were admitted to one of two level-I regional trauma centers between 1983 and 1994 because of a fracture of the femoral shaft with a thoracic injury (an Abbreviated Injury Scale score of 2 points or more) or without a thoracic injury were studied retrospectively. The patient populations and the protocols for the treatment of trauma were similar at the two centers; however, the centers differed with regard to the technique that was used for acute stabilization of the fracture of the femoral shaft. At Center I intramedullary nailing with reaming was used in 217 (95 per cent) of the 229 patients, whereas at Center II a plate was used in 206 (92 per cent) of the 224 patients. This difference was used to investigate the effect of acute femoral reaming on the occurrence of adult respiratory distress syndrome in multiply injured patients who had a chest injury. Three groups of patients were evaluated: those who had both a fracture of the femur and a thoracic injury, those who had a fracture of the femur but no thoracic injury, and those who had a thoracic injury without a fracture of the femur or the tibia. The third group was studied at each center to determine if there was a difference between the institutions with regard to the rate of adult respiratory distress syndrome. Patients who had diabetes, chronic obstructive pulmonary disease, asthma, hepatic or renal failure, or an immunosuppressive condition were excluded from the study. The records were abstracted to determine the Injury Severity Score, Abbreviated Injury Scale score, and Glasgow Coma Score for each patient. Requirements for fluid resuscitation were calculated for the first twenty-four hours; these included the number of units of packed red blood cells, fresh-frozen plasma, and platelets that were transfused and the volume of crystalloid that was used. The duration of intubation, the duration of hospitalization, and the occurence of adverse outcomes (death, multiple organ failure, adult respiratory distress syndrome, pneumonia, and pulmonary embolism) were determined for each patient. The groups of patients were analyzed as a whole and then were stratified into subgroups (according to whether or not they had a thoracic injury and whether the Injury Severity Score was less than 30 points or 30 points or more) to determine if the type of fixation of the femoral fracture affected the rate of adult respiratory distress syndrome or mortality. Logistic regression models were used to analyze the data. The over-all occurrence of adult respiratory distress syndrome in the 453 patients who had a femoral fracture was only 2 per cent (ten patients). The rates of adult respiratory distress syndrome for the patients who had a thoracic injury but no femoral fracture (eight [6 per cent] of 129 patients at Center I, compared with ten [8 per cent] of 125 patients at Center II) did not differ between centers, suggesting that the institutions were comparable in their treatment of multiply injured patients. The occurrence of adult respiratory distress syndrome in the patients who had a femoral fracture without a thoracic injury did not differ substantially according to whether the fracture had been treated with a nail (118 patients) or a plate (114 patients). Likewise, the frequency of adult respiratory distress syndrome, pneumonia, pulmonary embolism, failure of multiple organs, or death for the patients who had a femoral fracture and a thoracic injury was similar regardless of whether nailing with reaming (117 patients) or a plate (104 patients) had been used. The use of intramedullary nailing with reaming for acute stabilization of fractures of the femur in multiply injured patients who have a thoracic injury without a major comorbid disease does not appear to increase the occurrence of adult respiratory distress syndrome, pulmonary embolism, failure of multiple organs, pneumonia, or death.

Early development of the oligodendrocyte in the embryonic chick metencephalon

It has been demonstrated that the spinal cord oligodendrocytes in the vertebrates arise in the ventral ventricular zone adjacent to the floor plate in their early development. Because of the similarities of basic structures in the spinal cord and metencephalon, it is probable that the mode of early oligodendrocyte development in the metencephalon is the same as that in the spinal cord. We examined this possibility in chick embryos, using monoclonal antibodies O1 and O4, markers for oligodendrocyte lineage. An O4-positive (O4+) cell focus was observed in the medial ventricular zone of E5 chick ventral metencephalon (the earliest stage examined), adjacent to the floor plate. At E6, O4+ cells were dispersed from the medial to the lateral pons and, at E7, to the cerebellar anlagen. O4+ cells in the E6 brainstem and in the E7 cerebellum were unipolar in shape, whereas one day later, some of the labeled cells were multipolar with a few thin processes. O1+ oligodendrocytes first appeared at E8 in the ventromedial part of the pons and were distributed throughout the pons at E10 and in the cerebellum at E12. Explants from three subdivisions of the metencephalon (medial and lateral pons, and cerebellum) from E5 to E8 chick embryos were separately cultured to confirm the potential for generation of oligodendrocyte lineage. O4+ cells appeared in the culture of the E5 medial pons (the earliest stage examined), in the E6 lateral pons, and in the E7 cerebellum. In addition, E7 was the youngest stage from which cerebellar explants were able to generate O1+ oligodendrocytes. Our results clearly demonstrated the in vivo morphology of oligodendrocyte precursors in the metencephalon and their developmental appearance in a ventral-to-dorsal manner. From the bipolar morphology of O4+ cells and the spacio-temporal continuity of the dispersion, it is inferred that the initial dispersion of O4+ cells may involve oligodendrocyte migration from the focus of the medial pons to the lateral and dorsal parts of the metencephalon.

Demonstration of the corticotectobulbar pathway from the orofacial motor cortex to the parvicellular reticular formation in the rat

We examined a corticotectobulbar pathway from the orofacial motor cortex (OfM) to the parvicellular reticular formation (RFp), where numerous premotor neurons for the orofacial motor nuclei were known to be distributed, light and electron microscopically by using a combination of anterograde and retrograde tracing techniques. After contralateral injections of biotinylated dextranamine (BDA) into the OfM and cholera toxin B subunit (CTb) into the RFp, the overlapping distribution of ipsilateral axon terminals labeled with BDA and contralateral neurons labeled with CTb was found in the lateralmost part of the superior colliculus (SC). Furthermore, contralateral injections of BDA into the OfM and wheat germ agglutinin-horseradish peroxidase (WGA-HRP) into the RFp resulted in that ipsilateral axons labeled with BDA made asymmetrical synaptic contacts with the dendrites of contralateral SC neurons labeled with WGA-HRP.

High affinity interaction of mouse DNA topoisomerase I with di- and trinucleotides corresponding to specific sequences of supercoiled DNA cleaved chain

Recently mouse DNA topoisomerase I (topo) was shown to possess high affinity for a single-stranded AAGACTTAG nonanucleotide (K(i) = 2.0 microM) corresponding to the scissile strand of the minimal DNA duplex, which is necessary for cleavage of supercoiled DNA. In order to determine the most important part of the above sequence for the DNA recognition by topo, the interactions of the enzyme with a set of extremely short (2-5 nucleotides in length) oligonucleotides corresponding to different parts of the nonanucleotide have been investigated. The affinities of different oligonucleotides corresponding to the CTTAG part of the sequence (K(i) = 0.13-0.92 mM) were shown to be significantly lower than that for the AAGA tetranucleotide (K(i) = 9.0 microM). Topo effectively recognized even short oligonucleotides containing only two or three bases (AGA and pAG, K(i) = 20 and 50 microM). We suppose that oligonucleotides having a high afffinity to the enzyme can offer a unique opportunity for the rational design of topoisomerase-targeting drugs.

Selective determination of haloperidol in human serum: surface ionization mass spectrometry and gas chromatography with surface ionization detection

Surface ionization organic mass spectrometry (SIOMS) has been performed on the clinically important drug haloperidol using quadrupole mass spectrometry in which the thermal ion source has a rhenium oxide emitter. The surface ionization (SI) mass spectrum is presented, interpreted in a purely empirical way by means of evidence from previous investigations, and then compared to results from conventional electron impact (EI) ionization. An approach to detection of this drug in serum by gas chromatography (GC) with a surface ionization detector (SID) and GC-SIOMS is described. This approach demonstrates that (a) haloperidol is efficiently surface-ionized, giving a unique SI mass spectrum, (b) experimental results rationalize the combined sensitivity and selectivity of the GC-SID for the examined drug, (c) the detection limit for haloperidol in serum is 1.1 ng/ml (S/N = 3) by GC-SID (the coefficients of variation of the assay are generally low, i.e., below 8.5%) and (d) the GC-SIOMS coupling can be used for sensitive and selective detection of haloperidol in serum.

Comparison of three methods for analysis of urinary sediments

Efficiency of urine sediment analysis was evaluated in 423 specimens including 86 documented renal disorder ones using three methods; a traditional centrifugal and microscopic one, an image-scanning one and a flow cytometric one. Among the three methods, good correlations were observed in white blood cells and epithelial cells. Between white blood cells and bacterial counts a good correlation was observed only in the flow cytometry one. Female specimens usually demonstrated high values in white blood cells except with the microscopic method. Casts in patients with renal disorder exhibited significantly high in the flow cytometric method. In all methods, proteinuria specimens showed high cast count in the sediment. From these results we concluded that the flow cytometric method was clinically useful, especially in urinary tract disorder specimens.