Biomedical subjects

M A Greco

Publications and source records attributed to M A Greco.

At least 19 recordsLinked to original sources

PubMed2003

Effects of lateral hypothalamic lesion with the neurotoxin hypocretin-2-saporin on sleep in Long-Evans rats.

Narcolepsy, a disabling neurological disorder characterized by excessive daytime sleepiness, sleep attacks, sleep fragmentation, cataplexy, sleep-onset rapid eye movement sleep periods and hypnagogic hallucinations was recently linked to a loss of neurons containing the neuropeptide hypocretin. There is considerable variability in the severity of symptoms between narcoleptic patients, which could be related to the extent of neuronal loss in the lateral hypothalamus. To investigate this possibility, we administered two concentrations (90 ng or 490 ng in a volume of 0.5 microl) of the neurotoxin hypocretin-2-saporin, unconjugated saporin or saline directly to the lateral hypothalamus and monitored sleep, the entrained and free-running rhythm of core body temperature and activity. Neurons stained for hypocretin or for the neuronal specific marker were counted in the perifornical area, dorsomedial and ventromedial nucleus of the hypothalamus. More neuronal nuclei (NeuN) cells were destroyed by the higher concentration of hypocretin-2-saporin (-55%) compared with the lower concentration (-34%) in the perifornical area, although both concentrations lesioned the hypocretin neurons almost equally well (high concentration=91%; low concentration=88%). The high concentration of hypocretin-2-saporin also lesioned neurons in the dorsomedial nucleus of the hypothalamus and ventromedial nucleus of the hypothalamus. Narcoleptic-like sleep behavior was produced by both concentrations of the hypocretin-2-saporin. The high concentration produced a larger increase in non-rapid eye movement sleep amounts during the normally active night cycle than low concentration. Neither concentration of hypocretin-2-saporin disrupted the phase or period of the core temperature or activity rhythms. The low concentration of unconjugated saporin did not significantly lesion hypocretin or neurons and did not alter sleep. The high concentration of unconjugated saporin produced some loss of neuronal nuclei-immunoreactive (NeuN-ir) neurons and hypocretin immunoreactive neurons, but only a transient increase in non-rapid eye movement sleep. These results led us to conclude that the extent of hypocretin neuronal loss together with an accompanying loss of cells in the lateral hypothalamus may explain the differences in severity of symptoms seen in human narcolepsy.

Animals↗

PubMed2003

Region-specific changes in immediate early gene expression in response to sleep deprivation and recovery sleep in the mouse brain.

Previous studies have documented changes in expression of the immediate early gene (IEG) c-fos and Fos protein in the brain between sleep and wakefulness. Such expression differences implicate changes in transcriptional regulation across behavioral states and suggest that other transcription factors may also be affected. In the current study, we examined the expression of seven fos/jun family member mRNAs (c-fos, fosB, fos related antigen (fra)1, fra-2, junB, c-jun, and junD) and three other IEG mRNAs (egr-1, egr-3, and nur77) in mouse brain following short-term (6 h) sleep deprivation (SD) and 4 h recovery sleep (RS) after SD. Gene expression was quantified in seven brain regions by real-time reverse transcription-polymerase chain reaction (RT-PCR). Multivariate analysis of variance revealed statistically significant variation in cerebral cortex, basal forebrain, thalamus and cerebellum. Levels of c-fos and fosB mRNA were elevated during SD in all four of these brain regions. In the cerebral cortex, junB mRNA was also elevated during SD whereas, in the basal forebrain, fra-1 and fra-2 mRNA levels increased in this condition. During RS, the only IEG mRNA to undergo significant increase was fra-2 in the cortex. C-jun and junD mRNAs were invariant across experimental conditions. These results indicate that the expression of fos/jun family members is diverse during SD. Among other IEGs, nur77 mRNA expression across conditions was similar to c-fos and fosB, egr-1 mRNA was elevated during SD in the cortex and basal forebrain, and egr-3 mRNA was elevated in the cortex during both SD and RS. The similarity of fosB and nur77 expression to c-fos expression indicates that these genes might also be useful markers of functional activity. Along with our previous results, the increased levels of fra-2 and egr-3 mRNAs during RS reported here suggest that increased mRNA expression during sleep is rare and may be anatomically restricted.

Analysis of Variance↗

PubMed2003

Small cells in hepatoblastoma lack "oval" cell phenotype.

Hepatoblastoma, a childhood tumor of the liver, is composed of epithelial and mesenchymal elements in varying proportions and at various stages of differentiation. The epithelial element recapitulates the stages of hepatocyte development from the primitive blastema through embryonal hepatocytes to fetal hepatocytes. The blastemal or undifferentiated cells have been postulated to represent neoplastic hepatocyte progenitor cells. In this study, we examine the immunophenotype of the various epithelial cells of hepatoblastoma with special emphasis on the small undifferentiated cell component and compare it with that of adult hepatocytes and hepatic stem (oval) cells. Putative stem cells in the liver can express all of the following markers: alpha-feto protein, CK19 (OV-6), chromogranin A, Bcl-2, HepPar-1, and alpha1 microglobulin. The latter, like alpha-feto protein, is a plasma protein synthesized by hepatocytes. Both alpha1 microglobulin and HepPar-1 are expressed in fetal liver cells as early as 7 weeks of intrauterine life. They are also expressed in hepatocellular carcinoma and in hepatocytic cell lines derived from normal fetal or adult liver. Formalin-fixed, paraffin-embedded archival tissues from 10 predominantly epithelial hepatoblastomas were immunostained with antibodies directed against CD 34, alpha1 microglobulin, Bcl-2, HepPar 1, and CK19 using the avidin-biotin-peroxidase method. The undifferentiated small cell component did not express any of the markers studied, namely, Bcl-2, HepPar-1, alpha(1) microglobulin, CD34, or CK19. Hepatocyte-like cells were alpha1 microglobulin- and HepPar-1-positive, with the intensity of staining correlating with the degree of hepatocytic differentiation. Bcl-2 expression was restricted to areas of ductular differentiation. CK19 was detected in foci that showed duct formation. The small cells of hepatoblastoma did not express HepPar-1, Bcl-2, CK19, alpha1 microglobulin, or CD34, markers that characterize the immunophenotype of hepatic stem cells ("oval" cells). Thus, this observation raises the following questions: (1) is "hepatoblastoma" a misnomer? (2) is the expression of tumor antigens dysregulated in hepatoblastoma? (3) does the liver have two different types of progenitor cells, oval cells and blastemal cells, with differing immunophenotypes? and (4) do the blastemal cells, rather than oval cells, represent the more primitive progenitor cells of the liver?

Cell Differentiation↗

PubMed2002

Appropriate and inappropriate use of day-hospital care in Italy.

This study describes the extent of inappropriate day-hospital assistance and the effect of different variables on such inappropriateness. A random sample of patients admitted to pediatric and adult day-hospital care during the period Janurary--December 2000 in three hospitals located in the area of Catanzaro, Italy were reviewed. Assessment of appropriateness was made for the first access and for each of the following accesses in day-hospital. A total of 826 patients were reviewed. Overall, 23.8% of the first access in day-hospital care was judged to be inappropriate and 49.7% of the sample showed at least one inappropriate access for day-hospital care with a mean of 1.4 inappropriate accesses. Multiple logistic regression analysis indicated that the inappropriateness of the first access significantly increased with relation to lower distance from hospital to patient's home; admission to general medicine wards; first access from Monday to Thursday; lower number of patient's diagnostic procedures and medical examinations in the first access. Stepwise multiple linear regression analysis showed that the number of inappropriate accesses was significantly higher for general medicine and surgery and trauma/orthopedics wards; in patients who the first access was inappropriate; in those who received a lower number of diagnostic procedures and medical examinations; in patients who showed a higher length of care in day-hospital. The findings suggest the need for standardized diagnostic and therapeutic guidelines for day-hospital care.

Adolescent↗

PubMed2001

Complement-independent, peroxide-induced antibody lysis of platelets in HIV-1-related immune thrombocytopenia.

Immunologic thrombocytopenia is seen commonly in HIV-1 infection. The pathogenesis of this problem has been unclear, but it is associated with circulating immune complexes that contain platelet membrane components and anti-platelet membrane GPIIIa49-66 IgG antibodies. These antibodies cause acute thrombocytopenia when injected into mice. We now show that purified anti-GPIIIa49-66 causes platelet fragmentation, in vitro in the absence of complement, and in vivo in wild-type and C3-deficient mice. The mechanism of complement-independent platelet lysis is shown to be caused by the antibody-induced generation of H202, as indicated by in vitro experiments with inhibitors of reactive oxygen species, and in vivo studies carried out with p47phox-deficient mice. Thus, a novel mechanism of immunologic platelet clearance is described in which an anti-platelet IgG causes platelet fragmentation via the induction of reactive oxygen species.

Animals↗

PubMed2001

Hypocretin receptor protein and mRNA expression in the dorsolateral pons of rats.

The hypocretins (also known as orexins) are hypothalamic peptides that have been implicated in feeding and sleep regulation. Previous reports have described the distribution of the mRNAs encoding two hypocretin receptors (HCRT-R), but the pattern of protein expression has not been investigated. Here we examine the distribution of the mRNA and protein for the HCRT receptor 1 (HCRT-R1) and HCRT receptor 2 (HCRT-R2) in the pontine brainstem and demonstrate that they are present in many pontine nuclei including those associated with REM sleep. Immunohistochemistry indicates that one or both of the receptor subtypes are expressed in the dorsal raphe, the lateral dorsal tegmental (LDT), the pedunculo pontine (PPT), the locus coeruleus (LC), the locus subcoeruleus, pontis oralis, Barrington's, the trigeminal complex (mesencephalic trigeminal and motor nucleus of the trigeminal nerve), the dorsal tegmental nucleus of Gudden (DTG), the ventral cochlear nucleus (VCA), trapezoid nucleus (TZ), pontine raphe nucleus and the pontine reticular formation. These regions have been shown to be involved in mastication, bladder control, gastrointestinal function and in arousal. Given these projection sites and the functions associated with these sites, we suggest that HCRT may play a role in maintaining alertness and vigilance while the animal is engaged in consummatory behavior.

Animals↗

PubMed2000

Sleep and wakefulness in c-fos and fos B gene knockout mice.

G-protein coupled receptor (GPCR) stimulation has been implicated in the regulation of sleep. Upon stimulation of a GPCR an intracellular cascade involving second and third messengers is initiated. The latter include the fos-family of immediate early genes (IEGs). Although there is considerable evidence indicating that IEGs are expressed in response to sleep, the effects of their deletion on sleep is not known. The present study examined sleep-wakefulness in mice lacking the c-fos or fos B genes. Null c-fos mice compared to their wildtype (WT) and heterozygote (het) siblings had more wakefulness and less slow wave sleep (SWS); REM sleep was not affected. The null c-fos mice also had increased delta activity (0.3-4 Hz). In contrast, the null and heterozygote fos B mice had less REM sleep, but the time spent in SWS or wakefulness was not different from their wild-type (WT) siblings. In the null c-fos mice, the increased wakefulness and the reduction in SWS could not be due to a systemic alteration in temperature since the core temperature was similar in all mice. By demonstrating that these IEGs are involved in sleep, we suggest that the deletion of specific genes, even within a family of genes, can have a specific effect on sleep.

Animals↗

PubMed2000

Effect of lesions of the ventrolateral preoptic nucleus on NREM and REM sleep.

Neurons in the ventrolateral preoptic nucleus (VLPO) in rats show c-fos activation after sleep and provide GABAergic innervation of the major monoamine arousal systems, suggesting that they may be a necessary part of the brain circuitry that produces sleep. We examined the effects on sleep behavior in rats of cell-specific damage to the VLPO by microinjection of ibotenic acid. Severe lesions of the central cell cluster of the VLPO ( approximately 80-90% cell loss bilaterally) caused a 60-70% decrease in delta power and a 50-60% decrease in nonrapid-eye-movement (NREM) sleep time (p < 0.001). The number of remaining Fos-immunoreactive neurons in the VLPO cell cluster was linearly related to NREM sleep time (r = 0.77; p < 0.001) and total electroencephalogram delta power (r = 0. 79; p < 0.001) but not to rapid-eye-movement (REM) sleep (r = 0.35; p > 0.10). Lesions in the region containing scattered VLPO neurons medial or dorsal to the cell cluster caused smaller changes in NREM sleep time (24.5 or 15%, respectively) but were more closely associated with loss of REM sleep (r = 0.74; p < 0.01). The insomnia caused by bilateral VLPO lesions persisted for at least 3 weeks. Lesions of the VLPO caused no change in mean body temperature or its circadian variation; after small lesions of the ventromedial preoptic nucleus, body temperature showed normal circadian variation but a wider temperature range, and sleep behavior was not affected. These experiments delineate distinct preoptic sites with primary effects on the regulation of NREM sleep, REM sleep, and body temperature.

Animals↗

PubMed2000

c-Fos expression in the cholinergic basal forebrain after enforced wakefulness and recovery sleep.

The present study used c-Fos expression to examine cellular activity in cholinergic regions in the basal forebrain (BF) following enforced waking and recovery sleep. Cholinergic cells within the vertical and horizontal limbs of the diagonal band of Broca (VDB and HDB, respectively) showed significantly higher c-Fos immunoreactivity after prolonged waking than after recovery sleep. Cholinergic cells within the medial septal nucleus (MS), however, showed no change in c-Fos expression under these conditions. Consistent with our previous findings, c-Fos immunoreactivity in the ventral lateral preoptic area (VLPO) was increased after 1-2h of recovery sleep compared with enforced waking. These results indicate state-specific effects on transcription and subsequent protein expression in cell populations associated with behavioral state and further show that the HDB, VDB and VLPO are good candidates for the further study of intracellular events associated with sleep and wakefulness.

Animals↗

PubMed2000

Vascular apoptosis and involution in gliomas precede neovascularization: a novel concept for glioma growth and angiogenesis.

Vascular changes in gliomas were analyzed by implanting fluorescent-labeled glioma 261 cells in the brains of 28 mice. Seven animals were killed each week for 4 weeks. We investigated the expression of angiopoietin-2 (Ang-2) by in situ hybridization and compared it with the distribution of apoptotic cells identified by DNA strand breaks (using the terminal deoxynucleotidyl transferase-mediated biotinylated deoxyuridine triphosphate nick end labeling [TUNEL] method) and transmission electron microscopy (TEM). As early as 1 week after implantation, tumor cells accumulated around vessels, which expressed Ang-2 and were TUNEL negative. TEM showed tumor cells adjacent to the vascular cells "lifting up" the normal astrocytic feet processes away from the endothelial cells and disrupting normal pericytic cuffing. After 2 weeks the number of perivascular glioma cells had increased. No increase in the number of blood vessels was detected at this time. Vascular cells remained positive for Ang-2 and rare ones were TUNEL positive. TEM showed closely packed proliferating perivascular tumor cells. After 3 weeks, there was vascular involution with scant zones of tumor necrosis. Ang-2 was still detected in vascular cells, but now numerous vascular cells were TUNEL positive. In addition, TEM showed apoptotic vascular cells. After 4 weeks, there were extensive areas of tumor necrosis with pseudopalisading and adjacent angiogenesis. Ang-2 was detected in vascular cells at the edge of the tumors in the invaded brain and in vessels surrounded by tumor cells. At both 3 and 4 weeks, most of the TUNEL-positive tumor cells lacked morphological features characteristic of apoptosis and displayed features consistent with necrotic cell death as determined by TEM. Only rare tumor cells appeared truly apoptotic. In contrast, the TUNEL-positive endothelial cells and pericytes were round and shrunken, with condensed nuclear chromatin by TEM, suggesting that vascular cells were undergoing an apoptotic cell death. These results suggest that vascular cell apoptosis and involution preceded tumor necrosis and that angiogenesis is a later event in tumor progression in experimental gliomas. Moreover, Ang-2 is detected prior to the onset of apoptosis in vascular cells and could be linked to vascular involution.

Angiopoietin-2↗

PubMed2000

Compensatory sleep response to 12 h wakefulness in young and old rats.

There is a pronounced decline in sleep with age. Diminished output from the circadian oscillator, the suprachiasmatic nucleus, might play a role, because there is a decrease in the amplitude of the day-night sleep rhythm in the elderly. However, sleep is also regulated by homeostatic mechanisms that build sleep drive during wakefulness, and a decline in these mechanisms could also decrease sleep. Because this question has never been addressed in old animals, the present study examined the effects of 12 h wakefulness on compensatory sleep response in young (3.5 mo) and old (21.5 mo) Sprague-Dawley and F344 rats. Old rats in both strains had a diminished compensatory increase in slow-wave sleep (SWS) after 12 h of wakefulness (0700-1900, light-on period) compared with the young rats. In contrast, compensatory REM sleep rebound was unaffected by age. To assess whether the reduced SWS rebound in old rats might result from loss of neurons implicated in sleep generation, we counted the number of c-Fos immunoreactive (c-Fos-ir) cells in the ventral lateral preoptic (VLPO) area and found no differences between young and old rats. These findings indicate that old rats, similar to elderly humans, demonstrate less sleep after prolonged wakefulness. The findings also indicate that although old rats have a decline in sleep, this cannot be attributed to loss of VLPO neurons implicated in sleep.

Adaptation, Physiological↗

PubMed2000

Distribution of hypocretin-containing neurons in the lateral hypothalamus and C-fos-immunoreactive neurons in the VLPO.

The present study investigated the distribution of neurons implicated in the regulation of sleep in three species generally used in sleep research, i.e., mice, rats and cats. We focused on sleep active neurons in the ventral lateral preoptic (VLPO) area and the hypocretin/orexin-containing neurons in the lateral hypothalamus. The latter groups of neurons were found recently to play an important role in the regulation of REM sleep. The expression of the transcription factor, c-Fos, was used to identify the VLPO. In mice and rats, in response to sleep, a discrete cluster of c-Fos positive cells was found in the VLPO. In mice, this cluster was located more medially compared to the rat, and as in the rat, galanin immunostained neurons were found in the VLPO. In the cat, c-Fos positive cells did not segregate to a specific location but were more diffusely represented in the preoptic area. In all three species, orexin/hypocretin-containing neurons were located only in the lateral hypothalamus with the distribution being more diffuse in the cat. The grouping of sleep-active cells in rodents makes it feasible to extract these cells for tissue culture and molecular analysis. Moreover, given that rodents have a distinct circadian distribution of sleep-wakefulness, the connectivity with the suprachiasmatic nucleus can also be determined.

Animals↗

PubMed1999

Congenital cystic adenomatoid malformation of the lung (CCAM): evaluation of the cellular components.

Congenital cystic adenomatoid malformation of the lung (CCAM) is a rare congenital lesion whose pathogenesis is not well defined. It is generally accepted that the various types of CCAMs originate at different levels of the tracheobronchial tree. To further define the pathogenesis of CCAM, we evaluated the cellular composition of different CCAM types by immunohistochemistry. Twenty-two CCAMs (17 CCAM type 1, two type 2, one type 3, and two type 4) were collected. The cellular composition was determined using immunohistochemical stains for type I cell-associated antigen (T1 cell-Ag), surfactant proteins and surfactant protein precursors (SP-A, SP-B, proSP-B, and proSP-C), neuroendocrine cells (GRP), Clara cells (UP-1), and the adhesion molecule CD44v6, a glycoprotein thought to be involved in cell-matrix and cell-cell interactions. Eleven fetal lungs also were analyzed to compare cytodifferentiation of the epithelial-lined cysts of the different types of CCAM with the stages of normal lung development. Our results indicate that CCAM is caused by an arrest in lung development, and, on the basis of cytodifferentiation, two major subtypes can be distinguished. One subtype consisting of CCAM types 1, 2, and 3 that shows a bronchiolar type of epithelium and a second subtype, consisting of CCAM type 4, that has an acinar-alveolar type of epithelium. Our findings also suggest that these two subtypes may arise at different stages of the branching of the bronchopulmonary tree, the first at the pseudoglandular stage and the second at the saccular stage.

Antigens, Neoplasm↗

PubMed1999

Choline acetyltransferase expression during periods of behavioral activity and across natural sleep-wake states in the basal forebrain.

The present study examined whether the expression of the messenger RNA encoding the protein responsible for acetylcholine synthesis is associated with sleep-wakefulness. Choline acetyltransferase messenger RNA levels were analysed using a semi-quantitative assay in which reverse transcription was coupled to complementary DNA amplification using the polymerase chain reaction. To examine the relationship between steady-state messenger RNA and behavioral activity, rats were killed during the day (4.00 p.m.) or night (4.00 a.m.), and tissue from the vertical and horizontal limbs of the diagonal bands of Broca was analysed. Choline acetyltransferase messenger RNA levels were higher during the day than during the night. The second study examined more closely the association between choline acetyltransferase messenger RNA levels and individual bouts of wakefulness, slow-wave sleep or rapid eye movement sleep. Choline acetyltransferase messenger RNA levels were low during wakefulness, intermediate in slow-wave sleep and high during rapid eye movement sleep. In contrast, protein activity, measured at a projection site of cholinergic neurons of the basal forebrain, was higher during wakefulness than during sleep. These findings suggest that choline acetyltransferase protein and messenger RNA levels exhibit an inverse relationship during sleep and wakefulness. The increased messenger RNA expression during sleep is consistent with a restorative function of sleep.

Animals↗

PubMed1998

Apoptosis of undifferentiated progenitors and granule cell precursors in the postnatal human cerebellar cortex correlates with expression of BCL-2, ICE, and CPP32 proteins.

Naturally occurring apoptotic cells have been demonstrated in the postnatal cerebellum of rodents (Wood et al. [1993] Neuron 11:621-632; Krueger et al. [1995] J. Neurosci. 15:3366-3374). The nature of these cells differs among species: they are considered to be granule cells in mouse and astrocytes in rat. We labeled proliferating and apoptotic cells in the postnatal human cerebellar cortex by using antibodies against the Ki-67/proliferating cell nuclear antigen and the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling method for fragmented DNA. We also immunocytochemically detected some proteins encoded by genes modulating apoptosis and specific markers of neuronal/glial differentiation. Proliferating cells were observed from birth to 4 months, representing 31-35% of cells within the external granular layer (EGL). Apoptotic cells were detected during the first 3 months and corresponded to 5-7% of EGL cells. Much lower percentages were calculated in other cortical layers and white matter. The balance between proliferation and apoptosis was quantitatively favorable to the latter during the first postnatal week. Expression of BCL-2, CPP32, and interleukin-1beta-converting enzyme (ICE) proteins was spatially and developmentally regulated in parallel with apoptosis. Apoptotic cells were often CPP32/ICE immunoreactive but negative for BCL-2. Some apoptotic cells were positive for vimentin and, less frequently, for alpha-internexin or type-III beta tubulin, but never expressed the glial fibrillary acidic protein. This study demonstrates that apoptosis is a significant phenomenon in early postnatal development of human cerebellar cortex and shares some of the regulatory mechanisms described in other vertebrates.

Antibodies↗

PubMed1998

Villin, cytokeratin 7, and cytokeratin 20 expression in pulmonary adenocarcinoma with ultrastructural evidence of microvilli with rootlets.

Villin (V) is a glycoprotein of microvilli associated with rootlet formation. Most colonic adenocarcinomas have a V positive (+), cytokeratin (CK) 20 (+), CK7-negative (-) immunophenotype; most lung adenocarcinomas have a CK20(-), CK7(+) immunophenotype. The reports of villin immunoreactivity in lung adenocarcinoma range from 6% to 68% in studies using various fixations and varied anti-villin antibodies. Some lung adenocarcinomas have microvilli with rootlets leading to possible diagnostic confusion with metastatic colonic adenocarcinoma to lung. Nine primary lung adenocarcinomas with rootlets on ultrastructure (including four bronchioloalveolar carcinomas [BAC]), four metastatic lung adenocarcinomas with rootlets, nine metastatic colon adenocarcinomas to lung, and 10 randomly selected lung adenocarcinomas without rootlets (including five BAC), were immunostained with monoclonal antibodies to villin (1D2C3), CK7 (OV-TL12/30), and CK20 (Ks20.8) using a streptavidin peroxidase technique with heat-induced epitope retrieval. All primary lung adenocarcinomas with rootlets were CK7(+) CK20(-), and six of nine (67%) were V(+). Cytoplasmic villin positivity occurred in a diffuse--five of nine (56%), focal--two of nine (22%), or brush border pattern--two of nine (22%). Two of four metastatic lung adenocarcinomas with rootlets were V(+). One metastatic lung adenocarcinoma had a CK7(+), CK20(+), V(-) phenotype. All metastatic colonic adenocarcinomas were V(+), CK20(+), CK7(-), and 1 of 10 (10%) lung adenocarcinomas without rootlets was V(+), and all 10 were CK20(-), and CK7(+). In summary, villin positivity is more common in lung adenocarcinoma with rootlets (67%) than those without rootlets (10%). AU primary lung adenocarcinomas were CK7(+), CK20(-). The combination of villin, CK 7, and CK 20 is helpful in differentiating metastatic colon adenocarcinoma from lung adenocarcinoma with rootlets.

Adenocarcinoma↗

PubMed1998

Expression of cholinergic markers in the pons of Flinders rats.

The Flinders sensitive line of rats (FSL rats) have an altered REM sleep pattern which includes a shorter REM sleep latency and an increased percentage of REM sleep [R.M. Benca, D.H. Overstreet, M.A. Gilliland, D. Russell, B.M. Bergmann, W.H. Obermeyer, Increased basal REM sleep but no difference in dark induction or light suppression of REM sleep in Flinders rats with cholinergic supersensitivity, Neuropsychopharmacology 15 (1996) 45-51; P.J. Shiromani, D.H. Overstreet, D. Levy, C.A. Goodrich, S.A. Campbell, J. C. Gillin, Increased REM sleep in rats selectively bred for cholinergic hyperactivity, Neuropsychopharmacology 1 (1988) 127-133]. Cholinergic mechanisms have been implicated in REM sleep generation [reviewed in P.J. Shiromani, J.C. Gillin, S.J. Henriksen, Acetylcholine and the regulation of REM sleep: basic mechanisms and clinical implication for affective illness and narcolepsy, Annu. Rev. Pharmacol. Toxicol. 27 (1987) 137-156]. In the present study, specific aspects of the cholinergic system were examined in the pontine region of the FSL rats. The number of cholinergic neurons in the LDT and PPT were not different in FSL and control rats. Analysis of steady state levels of mRNAs encoding the acetylcholine synthesizing protein, choline acetyltransferase (ChAT) or the m2, m3 and m5 muscarinic receptor subtypes were also comparable in FSL and control rats. These data raise the possibility that the cellular events underlying the altered REM sleep pattern in FSL rats may include mechanisms that effect the muscarinic or nicotinic receptor in the pons.

Acetylcholine↗

PubMed1998

Immunohistochemical evaluation of hepatoblastomas with use of the hepatocyte-specific marker, hepatocyte paraffin 1, and the polyclonal anti-carcinoembryonic antigen.

The distinction of hepatoblastoma, especially the embryonal type, from other small, round-cell tumors of childhood can sometimes be difficult. Polyclonal anticarcinoembryonic antigen (pCEA) and Hepatocyte Paraffin 1 (Hep Par 1) are immunohistochemical markers that are useful in the diagnosis of hepatocellular carcinomas. We immunohistochemically studied pCEA, monoclonal CEA (mCEA), and Hep Par 1 on 12 hepatoblastomas (3 fetal type, 2 embryonal type, and 7 mixed epithelial type). In addition, we studied the expression of Hep Par 1 on 27 other selected childhood tumors, including 1 hepatocellular carcinoma, 5 germ-cell tumors, 4 peripheral neuroectodermal tumors/Ewing's sarcomas, 3 rhabdomyosarcomas, 5 neuroblastomas, 2 rhabdoid tumors, 3 lymphomas, and 4 Wilms' tumors. All of the hepatoblastomas expressed Hep Par 1 with a characteristic granular intracytoplasmic pattern that was generally less intense in embryonal-type than in fetal-type hepatoblastomas, perhaps reflecting the degree of hepatocyte differentiation. All of the fetal-type hepatoblastomas expressed pCEA with both an intracytoplasmic and bile canalicular pattern. Embryonal type hepatoblastomas were more likely to be pCEA negative or to show focal or no canalicular pattern of expression, again possibly reflecting the degree of hepatocyte differentiation. All of the hepatoblastomas were mCEA negative. All of the nonhepatoblastomas were Hep Par 1 negative, except for the one hepatocellular carcinoma in this study, which was Hep Par 1 positive. We conclude that Hep Par 1 and pCEA are useful markers for hepatoblastomas, as they have been shown to be in hepatocellular carcinomas.

Adolescent↗