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.

A light and electron microscope study of the connections between the preganglionic fibers and the intralingual ganglion cells in the rat

The topographical distribution of the preganglionic neurons sending projection fibers to the tongue, and the connections between their fibers and the intralingual ganglion cells, were examined in the rat. When horseradish peroxidase injections were made into the anterior two-thirds of the tongue, labeled neuronal cell bodies were distributed mainly in the lateral reticular formation at the level between the rostral part of the facial nucleus and the caudal part of the superior olivary complex. On the other hand, after horseradish peroxidase injections into the posterior one-third of the tongue, labeled neuronal cell bodies were found mainly in the rostromedial part of the nucleus of the solitary tract, and additionally in the lateral reticular formation just ventral to the rostral part of the nucleus of the solitary tract. In both cases, labeled neuronal cell bodies were always found in the hypoglossal nucleus. The anterograde tracing study with Phaseolus vulgaris-leucoagglutinin or Fluoro-ruby confirmed the topographical organization suggested by the retrograde tracing study; when the tracer injections were centered on the lateral reticular formation at the level of the rostral part of the facial nucleus or on the rostral part of the nucleus of the solitary tract, labeled fibers distributed mainly in the anterior or posterior part of the tongue, respectively. It was also shown that the axon terminals of the preganglionic fibers labeled with Fluoro-ruby made close contacts with the intralingual ganglion cells immunopositive for neuron specific enolase. The electron microscopy combined with the anterograde tracing method with biotinylated dextran amine further indicated that the preganglionic fibers made synaptic contacts with the soma and dendritic processes of the intralingual ganglion cells.

Pain and satisfaction with pain control in seriously ill hospitalized adults: findings from the SUPPORT research investigations. For the SUPPORT investigators. Study to Understand Prognoses and Preferences for Outcomes and Risks of Treatmentm

OBJECTIVES

To evaluate the pain experience of seriously ill hospitalized patients and their satisfaction with control of pain during hospitalization. To understand the relationship of level of pain and dissatisfaction with pain control to demographic, psychological, and illness-related variables.

DESIGN

Prospective, cohort study.

SETTING

Five teaching hospitals.

PATIENTS

Patients for whom interviews were available about pain (n = 5,176) from a total of 9,105 patients in the Study to Understand Prognoses and Preferences for Outcomes and Risks of Treatments (SUPPORT).

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Patients were interviewed after study enrollment about their experiences with pain. When patients could not be interviewed due to illness, we used surrogate (usually a family member) responses calibrated to patient responses (from the subset of interviews with both patient and surrogate responses). Ordinal logistic regression was used to study the association of variables with level of pain and satisfaction with its control. Nearly 50% of patients reported pain. Nearly 15% reported extremely severe pain or moderately severe pain occurring at least half of the time, and nearly 15% of those patients with pain were dissatisfied with its control. After adjustment for confounding variables, older and sicker patients reported less pain, while patients with more dependencies in activities of daily living, more comorbid conditions, more depression, more anxiety, and poor quality of life reported more pain. Patients with colon cancer reported more pain than patients in other disease categories. Levels of reported pain varied among the five hospitals and also by physician specialty. After adjustment for confounding variables, dissatisfaction with pain control was more likely among patients with more severe pain, greater anxiety, depression, and alteration of mental status, and lower reported income; dissatisfaction with pain control also varied among study hospitals and by physician specialty.

CONCLUSIONS

Pain is common among severely ill hospitalized patients. The most important variables associated with pain and satisfaction with pain control were patient demographics and those variables that reflected the acute illness. Pain and satisfaction with pain control varied significantly among study sites, even after adjustment for many potential confounders. Better pain management strategies are needed for patients with the serious and common illnesses studied in SUPPORT.

Structure and organization of the gene encoding human selenoprotein

We have isolated a genomic clone encoding human selenoprotein P including the putative promoter region. The gene spans 12 kb and consists of five exons with a start codon in the second exon. A typical TATA sequence, the recognition motifs for a GATA-binding factor and the liver-specific factors, HNF-1 and HNF-3, were detected upstream from the transcription start point.

Comparative study of rbcL gene sequences in Fagopyrum and related taxa

Four species of Fagopyrum, two species of Persicaria and one species of Rumex were analyzed for the DNA sequences of their rbcL genes. In addition to these seven species, we analyzed the published or available sequence data of ten related taxa in Polygonales, Plumbaginales and Caryophyllales. By estimating the base substitution rate between each pair of species, and by constructing phylogenetic trees we concluded that: 1) In Fagopyrum, F. cymosum and F. tataricum are much more closely related than expected previously; this confirms the conclusion of Kishima et al. (1995). 2) The new classification of Fagopyrum species proposed by Ohnishi and Matsuoka (1996) based on morphology, isozyme and cpDNA variability is consistent with the rbcL sequences. 3) The Polygonales and the Plumbaginales should be separated from the Caryophyllales as concluded by Giannasi et al. (1992). 4) The separation of Fagopyrum from other genera in the Polygoneae has a solid molecular basis.

Reactive oxygen species involved in the glutamate toxicity of C6 glioma cells via xc antiporter system

We recently demonstrated that continuous L-glutamate exposure led to cell death in C6 glioma cells over a period of 24-36 h, due to inhibition of cystine uptake through the cystine/glutamate (XC) antiporter. The antioxidant vitamin E provided protection against this effect, supporting the hypothesis that depletion of glutathione might be responsible, resulting from insufficient cystine uptake. To clarify the content of oxidative stress after glutathione depletion, the present study was done to investigate accumulation and target molecules of reactive oxygen species induced by glutamate treatment. The accumulation of reactive oxygen species was increased three-fold as compared to a control culture. Membrane oxidation, as judged by lipid peroxidation, was increased two-fold after glutamate treatment. Cellular ATP content was significantly reduced by glutamate exposure. For the two cytosolic enzymes examined, activity of glyceraldehyde 3-phosphate dehydrogenase was slightly enhanced by glutamate treatment, while activity of glutamine synthetase was not changed. Impairment of nuclear DNA after glutamate exposure was also revealed by nuclear chromatin condensation with DNA fragmentation. Thus, the multiple targets (membrane, cytoplasm and nuclei) of oxygen radicals in glutamate toxicity through the xc antiporter system were evaluated for the first time. Furthermore, prevention from cell death and from cellular toxicity induced by oxygen radicals could be seen using three specific oxygen radical scavengers, catalase, 3,3,5,5-tetramethyl-pyrroline N-oxide and alpha-phenyl-N-t-butylnitrone, without restoring the glutathione deficit. This indicates that radical scavengers did not interact with the xc antiporter system, but directly scavenged the oxygen radicals. Taken together, the data strongly suggest that O2-, H2O2 and OH accumulate in response to oxidative stress after glutathione depletion, resulting in glutamate cell death of C6 glioma cells.

Gene transfer into human bone marrow hematopoietic cells mediated by adenovirus vectors

Human bone marrow mononuclear cells (BMMNCs) and enriched CD34 positive (CD34+) cells were transduced with adenovirus vectors encoding Escherichia coli beta-galactosidase gene. Tranductions were carried out by 24-hour coincubation with adenovirus vectors at different multiplicities of infections (moi). Efficacy of gene transfer into BM cells and expression of the gene product (ie, beta-galactosidase) were studied using X-Gal histochemical staining and flow cytometric analysis. X-Gal staining demonstrated that the percentage of positive cells at mois of 5 to 500 was 3.4% to 34.5% for BMMNCs and 6.0% to 20.0% for enriched CD34+ cells. Similar results (1.5% to 35.7% for BMMNCs and 5.4% to 24.2% for enriched CD34+ cells) were obtained with flow cytometric analysis using fluorescein di-beta-D-galactopyranoside (FDG). Multicolor flow cytometry analysis, which included FDG, demonstrated that BM progenitors (CD34+ or CD34+CD38-), T cells (CD2+), B cells (CD19+), natural killer cells (CD56+), granulocytes, and monocytes all expressed the adenovirus transgene. To ascertain the effects of adenovirus vectors on normal BM progenitors, the numbers of colony forming unit-granulocyte/macrophage (CFU-GM), burst-forming unit-erythrocyte (BFU-E), and high-proliferative potential-colony-forming cells (HPP-CFC) after 24-hour coincubation with adenovirus vectors were determined. When BMMNCs or enriched CD34+ cells were incubated with adenovirus vectors at mois of 5 and 50, no significant differences in the numbers of CFU-GM, BFU-E, and HPP-CFC were observed compared with the uninfected control cells. However, the numbers of CFU-GM were significantly (P < .01) decreased when BMMNCs or enriched CD34+ cells were incubated with adenovirus vectors at a moi of 500, compared with the uninfected control cells. The adenovirus infected cells, purified by cell sorting for FDG expression, were capable of growing in culture and gave rise to various colonies (ie, CFU-GM, BFU-E, and HPP-CFC). These data indicate that recombinant adenovirus vectors can be used to transfer genes to human BM hematopoietic cells with expression of the exogenous gene at a high transduction efficiency.

Crigler-Najjar syndrome type II is inherited both as a dominant and as a recessive trait

Crigler-Najjar syndrome type II (CN-II) is caused by a severely reduced hepatic activity of bilirubin UDP-glucuronosyltransferase (UGT). Recently, by the analysis of the genetic background of CN-II patients, it has been clarified that the patients carry homozygous missense mutations or nonsense plus missense mutations on the gene for UGT, and CN-II was inherited as an autosomal recessive trait. We encountered a new case which had a nonsense mutation caused by a single nucleotide substitution on one allele. This indicates that CN-II is also inherited as a dominant trait as well as a recessive trait. Expression study in vitro strongly suggests that the disease in this case is caused by a dominant negative mutation by forming a heterologous subunit structure.

A nigro-rubro-bulbar pathway to the parvicellular reticular formation in the rat

A possible pathway from the substantia nigra pars reticulata (SNr) to the parvicellular reticular formation (RFp) via the red nucleus (RN) was examined light and electron microscopically by combining anterograde and retrograde tracing techniques. After contralateral injections of biotinylated dextranamine (BDA) into the dorsolateral part of the SNr and cholera toxin B subunit (CTb) into the RFp, many CTb-labelled neurones were distributed contralaterally in the dorsal part of the RN, where numerous BDA-labelled axon terminals originating from the ipsilateral SNr were found. After contralateral injections of BDA into the dorsolateral part of the SNr and wheat germ agglutinin-horseradish peroxidase (WGA-HRP) into the RFp, ipsilateral axons labelled with BDA were found to make synaptic contacts with the somata and dendrites of contralateral neurones labelled with WGA-HRP in the dorsal part of the RN.

Distribution of nitric oxide synthase-containing nerves in the aganglionic intestine of mutant rats: a histochemical study

We examined the distribution of nerves containing nitric oxide synthase in the intestine of congenitally aganglionic rats, using a reduced nicotinamide adenine dinucleotide phosphate diaphorase histochemical method for whole-mount and cryostat specimens. A constricted intestinal segment extends from the terminal ileum to the anus in this mutant. No nerve elements with the activity were found in the affected terminal ileum, cecum and proximal colon. Although intrinsic ganglionic neurons were absent along the constricted intestine, nerve fibers with the activity were found in both the submucous and intermuscular layers distal to the proximal colon. These fibers increased in density towards the rectum, forming hypertrophic nerve bundles and unusual fiber networks. However, positive fibers were never seen within the circular and longitudinal musculature of the constricted lesion. Some of these hypertrophic nerve bundles were continuous with ectopic ganglia that were situated in the adventitial connective tissue around the lower rectum and in the submucosa near the anus. The hypertrophic nerve bundles seemed to have an extrinsic origin; some of them may have originated from ectopic ganglia. These results suggest that the defective distribution of nerves containing nitric oxide synthase may be involved in the pathogenesis of congenital colonic aganglionosis.

Changes of NADPH-diaphorase activity in the lumbosacral intermediolateral neurons of the rat after pelvic axotomy

Changes of nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) activity in the lumbosacral intermediolateral (IML) neurons of the rat were examined for approximately 10 weeks after pelvic nerve transection. Both the number and the staining intensity of NADPH-d-positive neurons in the IML region increased remarkably 1 week after pelvic axotomy; the number of darkly NADPH-d-stained cells on the axotomized side was approximately 2.2-fold greater than on the control side. The number of NADPH-d-positive cells returned to the control level at 5 weeks and decreased significantly below the control level 10-11 weeks postaxotomy. In addition, using a retrograde tracing technique with Fluorogold (FG) combined with NADPH-d histochemistry, approximately 95% of the NADPH-d-positive IML neurons were found to send their axons to the pelvic nerve 1 week after axotomy, whereas nearly 25% of the FG-labeled neurons were found to be negative for NADPH-d. Thus, these results indicate that pelvic axotomy in the rat enhances NADPH-d activity transiently in the IML neurons of the lumbosacral spinal cord, and suggest that the IML region may include different neurons showing different responses in nitric oxide synthase expression after peripheral axotomy.

The vestibular nuclei of the rat project to the lateral part of the thalamic parafascicular nucleus (centromedian nucleus in primates)

To clarify the vestibular projections to the centromedian-parafascicular nuclear complex, the Phaseolus vulgaris leucoagglutinin (PHA-L) and horseradish peroxidase conjugated to wheat germ agglutinin (WGA-HRP), tracing studies have been done in rats. The data demonstrated that the lateral parafasicular nucleus received vestibular afferents mainly from the ventral part of medial vestibular nucleus, and the superior and inferior vestibular nuclei, with an ipsilateral predominance. These findings suggest the vestibular influence to the motor loop of the basal ganglia thalamocortical projections.

Characteristics of distribution of peptide-containing nerve fibres in the atrioventricular valves of the rat

The distribution of vasoactive intestinal polypeptide-, neuropeptide Y-, and calcitonin gene-related peptide-immunoreactive nerve fibres was investigated in the atrioventricular valves of the rat. These nerve fibres were visualized by immunostaining of whole-mount preparations by the avidin-biotin-peroxidase complex method. Vasoactive intestinal polypeptide-immunoreactive nerve fibres were observed mainly in the anterior cusp of the mitral valve and, to a lesser extent, in the medial cusp of the tricuspid valve. Numerous neuropeptide Y-immunoreactive nerve fibres were found covering all of the cusps. Both types of peptidergic nerve fibre formed dense networks that consisted of interlacing and anastomosing nerve fibres. Calcitonin gene-related peptide-immunoreactive nerve fibres were seen in every cusp, but did not form a fine network. These results provide detailed anatomical information for evaluation of the possible roles of each type of peptide-containing nerve fibre in the function of atrioventricular valves.

Statistical analysis of passive surveillance disease registry data

Passive surveillance disease data involve a registry of individuals who are at risk of disease and who are not under active follow up. The most serious limitations with such data are incomplete ascertainment of cases of disease and little or no follow-up information on patient vital status. This paper considers whether it is possible to estimate disease risk from such data and, if not, what additional information is required. In general, relative risks based on passive surveillance data will be biased even under the assumption that the probability of disease reporting and the hazard of death from other causes are the same for all individuals in the registry. However if the disease is rare, this bias is negligible. Methods are developed for estimating absolute disease incidence rates by combining passive surveillance data with a cohort study. Analytic approaches are proposed for the situations when death rates from all other causes are known and also unknown, and it is found that there is little loss in efficiency even if death rates are not known. There are considerable gains in efficiency for estimating absolute disease incidence rates by supplementing a cohort study with passive surveillance registry data compared to using the cohort study alone, especially if the exposure is rare and the cohort study is small relative to the size of the registry. Intuitively, the cohort data provides information about absolute rates of disease, while the passive surveillance data provides information about relative risks. The methods are applied to a registry of patients with an artificial heart valve that is at risk of breaking.

Origins of nerve fibers containing nitric oxide synthase in the rat celiac-superior mesenteric ganglion

The origin of nitric oxide synthase-containing nerve fibers in rat celiac-superior mesenteric ganglion was examined using retrograde tracing techniques combined with the immunofluorescence method. Fluoro-Gold was injected into the celiac-superior mesenteric ganglion. Neuronal cell bodies retrogradely labeled with Fluoro-Gold in the thoracic spinal cord, the dorsal root ganglia at the thoracic level, the nodose ganglion, and the intestine from the duodenum to the proximal colon were examined for nitric oxide synthase immunoreactivity. About 60% of sympathetic preganglionic neurons in the intermediolateral nucleus projecting to the celiac-superior mesenteric ganglion were immunoreactive for nitric oxide synthase, as were approximately 27% of nodose ganglion neurons and about 65% of dorsal root ganglion neurons projecting to the celiac-superior mesenteric ganglion. Neurons projecting to the celiac-superior mesenteric ganglion were found in the myenteric plexus of the small and large intestine. In the proximal colon, about 23% of such neurons were immunoreactive for nitric oxide synthase. However, in the small intestine, no immunoreactivity was found in these neurons.