934 resultados para ALPHA-1-ACID GLYCOPROTEIN
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Ginkgolides are potent blockers of the glycine receptor Cl- channel (GlyR) pore. We sought to identify their binding sites by comparing the effects of ginkgolides A, B and C and bilobalide on alpha 1, alpha 2, alpha 1 beta and alpha 2 beta GlyRs. Bilobalide sensitivity was drastically reduced by incorporation of the beta subunit. In contrast, the sensitivities to ginkgolides B and C were enhanced by beta subunit expression. However, ginkgolide A sensitivity was increased in the alpha 2 beta GlyR relative to the alpha 2 GlyR but not in the alpha 1 beta GlyR relative to the alpha 1 GlyR. We hypothesised that the subunit-specific differences were mediated by residue differences at the second transmembrane domain 2' and 6' pore-lining positions. The increased ginkgolide A sensitivity of the alpha 2 beta GlyR was transferred to the alpha 1 beta GlyR by the G2'A (alpha 1 to alpha 2 subunit) substitution. In addition, the alpha 1 subunit T6'F mutation abolished inhibition by all ginkgolides. As the ginkgolides share closely related structures, their molecular interactions with pore-lining residues were amenable to mutant cycle analysis. This identified an interaction between the variable R2 position of the ginkgolides and the 2' residues of both alpha 1 and beta subunits. These findings provide strong evidence for ginkgolides binding at the 2' pore-lining position.
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Using immunohistochemistry and RNA analyses we examined the fate of components of a newly identified matrix that develops between granulosa cells (focimatrix, abbreviated from focal intraepithelial matrix) and of the follicular basal lamina in ovulating bovine ovarian follicles. Pre- and postovulatory follicles were generated by treatment with estradiol (Day 1), progesterone (Days 1-10), and prostaglandin analogue (Day 9) with either no further treatment (Group 1, n = 6) and or with 25 mg porcine LH (Day 11, Group 2, n = 8 or Day 10, Group 3, n = 8) and ovariectomy on Day 12 (12-14 hr post LH in Group 2, 38-40.5 hr in Group 3). In the time frame examined no loss of follicular basal lamina laminin chains beta 2 and gamma 1 or nidogen 1 was observed. In the follicular basal lamina collagen type IV alpha 1 and perlecan were present prior to ovulation; after ovulation collagen type IV alpha 1 was discontinuously distributed and perlecan was absent. Versican in the theca interna adjacent to the follicular basal lamina in preovulatory follicles was not observed post ovulation, however, the granulosa cells then showed strong cytoplasmic staining for versican. Expression of versican isoforms V0, V1, and V3 was detected at all stages. Focimatrix was observed in preovulatory follicles. It contained collagen type IV alpha 1, laminins beta 2 and gamma 1, nidogen 1 and perlecan and underwent changes in composition similar to that of the follicular basal lamina. In conclusion focimatrix and the follicular basal lamina are degraded at ovulation. Individual components are lost at different times.
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We investigate boundary critical phenomena from a quantum-information perspective. Bipartite entanglement in the ground state of one-dimensional quantum systems is quantified using the Renyi entropy S-alpha, which includes the von Neumann entropy (alpha -> 1) and the single-copy entanglement (alpha ->infinity) as special cases. We identify the contribution of the boundaries to the Renyi entropy, and show that there is an entanglement loss along boundary renormalization group (RG) flows. This property, which is intimately related to the Affleck-Ludwig g theorem, is a consequence of majorization relations between the spectra of the reduced density matrix along the boundary RG flows. We also point out that the bulk contribution to the single-copy entanglement is half of that to the von Neumann entropy, whereas the boundary contribution is the same.
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We have carried out a discovery proteomics investigation aimed at identifying disease biomarkers present in saliva, and, more specifically, early biomarkers of inflammation. The proteomic characterization of saliva is possible due to the straightforward and non-invasive sample collection that allows repetitive analyses for pharmacokinetic studies. These advantages are particularly relevant in the case of newborn patients. The study was carried out with samples collected during the first 48 hours of life of the newborns according to an approved Ethic Committee procedure. In particular, the salivary samples were collected from healthy and infected (n=1) newborns. Proteins were extracted through cycles of sonication, precipitated in ice cold acetone, resuspended and resolved by 2D-electrophoresis. MALDI TOF/TOF mass spectrometry analysis was performed for each spot obtaining the proteins’ identifications. Then we compared healthy newborn salivary proteome and an infected newborn salivary proteome in order to investigate proteins differently expressed in inflammatory condition. In particular the protein alpha-1-antitrypsin (A1AT), correlated with inflammation, was detected differently expressed in the infected newborn saliva. Therefore, in the second part of the project we aimed to develop a robust LC-MS based method that identifies and quantifies this inflammatory protein within saliva that might represent the first relevant step to diagnose a condition of inflammation with a no-invasive assay. The same LC-MS method is also useful to investigate the presence of the F allelic variant of the A1AT in biological samples, which is correlated with the onset of pulmonary diseases. In the last part of the work we analysed newborn saliva samples in order to investigate how phospholipids and mediators of inflammation (eicosanoids) are subject to variations under inflammatory conditions and a trend was observed in lysophosphatidylcholines composition according to the inflammatory conditions.
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Signal integration determines cell fate on the cellular level, affects cognitive processes and affective responses on the behavioural level, and is likely to be involved in psychoneurobiological processes underlying mood disorders. Interactions between stimuli may subjected to time effects. Time-dependencies of interactions between stimuli typically lead to complex cell responses and complex responses on the behavioural level. We show that both three-factor models and time series models can be used to uncover such time-dependencies. However, we argue that for short longitudinal data the three factor modelling approach is more suitable. In order to illustrate both approaches, we re-analysed previously published short longitudinal data sets. We found that in human embryonic kidney 293 cells cells the interaction effect in the regulation of extracellular signal-regulated kinase (ERK) 1 signalling activation by insulin and epidermal growth factor is subjected to a time effect and dramatically decays at peak values of ERK activation. In contrast, we found that the interaction effect induced by hypoxia and tumour necrosis factor-alpha for the transcriptional activity of the human cyclo-oxygenase-2 promoter in HEK293 cells is time invariant at least in the first 12-h time window after stimulation. Furthermore, we applied the three-factor model to previously reported animal studies. In these studies, memory storage was found to be subjected to an interaction effect of the beta-adrenoceptor agonist clenbuterol and certain antagonists acting on the alpha-1-adrenoceptor / glucocorticoid-receptor system. Our model-based analysis suggests that only if the antagonist drug is administer in a critical time window, then the interaction effect is relevant.
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Tic-like movements in rodents bear close similarities to those observed in humans both pharmacologically and morphologically. Pharmacologically, tics are modulated by serotonergic and dopaminergic systems and abnormalities of these systems have been reported in Tourette's Syndrome (TS). Therefore, serotonergic and dopaminergic modulation of tics induced by a thyrotrophin-releasing hormone (TRH) analogue were studied as possible models for TS. The TRH analogue MK771 induced a variety of tic like movements in mice; blinking fore-paw-licking and fore-paw-tremor were quantified and serotonergic and dopaminergic modulation was investigated. The selective dopamine D1 receptor antagonists SCH23390 and SCH39166 and dopamine D2 antagonists raclopride and sulpiride had no effect on MK771 induced blinking. The D1 antagonists attenuated fore-paw-tremor and -licking while the D2 antagonists were generally without effect on these behaviours. Ketanserin (5-HT2A/ alpha-1 antagonist) and ritanserin (5-HT2A/2C antagonist) were able to attenuate MK771-induced blinking and ketanserin, mianserin (5-HT2A/2C antagonist) and prazosin (alpha-1 adrenoceptor antagonist) were able to attenuate MK771-induced fore-paw-tremor and -licking. The 5-HT2C/2B antagonist SB200646A was without effect on blinking and fore-paw-licking but dose-dependently potentiated fore-paw-tremor. The 5-HT1A agonists 8-OH DPAT and buspirone attenuated blinking at the lower doses tested but were ineffective at the higher doses; the converse was found for fore-paw-licking and -tremor behaviours.The effects of these ligands appeared to be at a postsynaptic 5-HTlA site since para-chlorophenylalanine was without effect on the manipulation of these behaviours. (S)-W A Y100135 was without effect on MK771-induced behaviours, spontaneous and DOl-induced head shakes. Because kynurenine potentiates head shakes and plasma concentrations are raised in TS patients the effects of kynurenine on the 5-HT2A/2C agonist DOl mediated head shake were established. Kynurenine potentiated the DOl head shake. Attempts were made to correlate serotonergic unit activity with tic like behaviour in cats but this proved unsuccessful. However, the pharmacological understanding of 5-HTlA receptor function has been hampered because of the lack of selective antagonists for this site. For this reason the effects of the novel 5-HTlA antagonists (S)-WA Y- 100135 and WAY -100635 were tested on 5-HT single-unit activity recorded from the dorsal-raphe-nucleus in the behaving cat. Both drugs antagonised the suppression of unit activity caused by 8-0H DPAT. (S)-WA Y-100135 reduced unit activity whereas WAY-100635 increased it. This suggests that WAY-100635 is acting as an antagonist at the 5-HTlA somatodendritic autoreceptor and that (S)W A Y -100135 acts as a partial agonist at this site. Aspects of tic like behaviour and serotonergic control are discussed.
A multimodal perspective on the composition of cortical oscillations:frontiers in human neuroscience
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An expanding corpus of research details the relationship between functional magnetic resonance imaging (fMRI) measures and neuronal network oscillations. Typically, integratedelectroencephalography(EEG) and fMRI,orparallel magnetoencephalography (MEG) and fMRI are used to draw inference about the consanguinity of BOLD and electrical measurements. However, there is a relative dearth of information about the relationship between E/MEG and the focal networks from which these signals emanate. Consequently, the genesis and composition of E/MEG oscillations requires further clarification. Here we aim to contribute to understanding through a series of parallel measurements of primary motor cortex (M1) oscillations, using human MEG and in-vitro rodent local field potentials. We compare spontaneous activity in the ~10Hz mu and 15-30Hz beta frequency ranges and compare MEG signals with independent and integrated layers III and V(LIII/LV) from in vitro recordings. We explore the mechanisms of oscillatory generation, using specific pharmacological modulation with the GABA-A alpha-1 subunit modulator zolpidem. Finally, to determine the contribution of cortico-cortical connectivity, we recorded in-vitro M1, during an incision to sever lateral connections between M1 and S1 cortices. We demonstrate that frequency distribution of MEG signals appear have closer statistically similarity with signals from integrated rather than independent LIII/LV laminae. GABAergic modulation in both modalities elicited comparable changes in the power of the beta band. Finally, cortico-cortical connectivity in sensorimotor cortex (SMC) appears to directly influence the power of the mu rhythm in LIII. These findings suggest that the MEG signal is an amalgam of outputs from LIII and LV, that multiple frequencies can arise from the same cortical area and that in vitro and MEG M1 oscillations are driven by comparable mechanisms. Finally, corticocortical connectivity is reflected in the power of the SMC mu rhythm. © 2013 Ronnqvist, Mcallister, Woodhall, Stanford and Hall.
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The Major Histocompatibility Complex (MHC) comprises the most polymorphic loci in animals. MHC plays an important role during the first steps of the immune response in vertebrates. In humans, MHC molecules (also named human leukocyte antigens, HLA) were initially regarded as class I or class II molecules. Each of them, presents to different T cells subsets. MHC class I molecules, are heterodimers in which the heavy chain (alpha) has three extracellular domains, two of which (alpha 1 and alpha 2) are polymorphic and conform the antigen recognition sites (ARS). The ARS is thought to be subjected to balancing selection for variability, which is the cause of the very high polymorphism of the MHC molecules. Different pathogenic epitopes would be the evolutionary force causing balancing selection. MHC class I genes have been completely sequenced (α1 and α2 protein domains) and thoroughly studied in Gallus gallus (chicken) as well as in mammals. In fact, the MHC locus was first defined in chicken, specifically in the highly consanguineous variety „Leghorn‟. It has been found that, in the case of chickens the MHC genetic region is considerably smaller than it is in mammals (remarkably shorter introns were found in chickens), and is organized quite differently. The noteworthy presence of short introns in chickens; supported the hypothesis that chicken‟s MHC represented a „minimal essential MHC‟. Until now, it has been assumed that chicken (order Galliformes) MHC was similar to all species included in the whole class Aves...
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Background: To validate STOPPFrail, a list of explicit criteria for potentially inappropriate medications (PIMs) in frailer older adults with limited life expectancy. A Delphi consensus survey of an expert panel (n = 17) comprising specialists in geriatric medicine, clinical pharmacology, palliative care, psychiatry of old age, clinical pharmacy and general practice.
Methods: STOPPFrail criteria was initially created by the authors based on clinical
experience and appraisal of the available literature. Criteria were organised according to physiological system. Each criterion was accompanied by an explanation. Panellists ranked their agreement with each criterion on a 5-point Likert scale and invited to provide written feedback. Criteria with a median Likert response of 4/5 (agree/strongly agree) and a 25th centile of ≥4 were included in the final criteria.
Results: Three Delphi rounds were required. All panellists completed all rounds. Thirty criteria were proposed for inclusion; 26 were accepted. No new criteria were added. The first two criteria suggest deprescribing medications with no indication or where compliance is poor. The remaining 24 criteria include lipid-lowering therapies, alpha-blockers for hypertension, anti-platelets, neuroleptics, proton pump inhibitors, H-2 receptor antagonists, anti-spasmodics, theophylline, leukotriene antagonists, calcium supplements, bone anti-resorptive therapy, selective oestrogen receptor modulators, non-steroidal antiinflammatories, corticosteroids, 5-alpha reductase inhibitors, alpha-1 selective blockers, muscarinic antagonists, oral diabetic agents, ACE-inhibitors, angiotensin receptor blockers, systemic oestrogens, multivitamins, nutritional supplements and prophylactic antibiotics. Anticoagulants and anti-depressants were excluded. Despite incorporation of panellists’ suggestions, memantine and acetyl-cholinesterase inhibitors remained inconclusive.
Conclusion: STOPPFrail comprises 26 criteria, which have been judged by broad consensus, to be potentially inappropriate in frailer older patients with limited life expectancy. STOPPFrail may assist in deprescribing medications in these patients.
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In this document we explore the issue of $L^1\to L^\infty$ estimates for the solution operator of the linear Schr\"{o}dinger equation, \begin{align*} iu_t-\Delta u+Vu&=0 &u(x,0)=f(x)\in \mathcal S(\R^n). \end{align*} We focus particularly on the five and seven dimensional cases. We prove that the solution operator precomposed with projection onto the absolutely continuous spectrum of $H=-\Delta+V$ satisfies the following estimate $\|e^{itH} P_{ac}(H)\|_{L^1\to L^\infty} \lesssim |t|^{-\frac{n}{2}}$ under certain conditions on the potential $V$. Specifically, we prove the dispersive estimate is satisfied with optimal assumptions on smoothness, that is $V\in C^{\frac{n-3}{2}}(\R^n)$ for $n=5,7$ assuming that zero is regular, $|V(x)|\lesssim \langle x\rangle^{-\beta}$ and $|\nabla^j V(x)|\lesssim \langle x\rangle^{-\alpha}$, $1\leq j\leq \frac{n-3}{2}$ for some $\beta>\frac{3n+5}{2}$ and $\alpha>3,8$ in dimensions five and seven respectively. We also show that for the five dimensional result one only needs that $|V(x)|\lesssim \langle x\rangle^{-4-}$ in addition to the assumptions on the derivative and regularity of the potential. This more than cuts in half the required decay rate in the first chapter. Finally we consider a problem involving the non-linear Schr\"{o}dinger equation. In particular, we consider the following equation that arises in fiber optic communication systems, \begin{align*} iu_t+d(t) u_{xx}+|u|^2 u=0. \end{align*} We can reduce this to a non-linear, non-local eigenvalue equation that describes the so-called dispersion management solitons. We prove that the dispersion management solitons decay exponentially in $x$ and in the Fourier transform of $x$.
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As Microcistinas são heptapeptídios cíclicos produzidos como metabólitos secundários por diferentes espécies de cianobactérias, sendo relevantes pelo seu potencial hepatotóxico. Peixes apresentam estratégias bioquímicas para detoxificar contaminantes ambientais, incluindo a ativação de enzimas de fase II de biotransformação, que incluem as isoformas de glutationa S-transferase (GST). As GST catalizam a conjugação de glutationa reduzida (GSH) com uma variedade de xenobióticos, incluindo as microcistinas. O presente estudo avaliou os níveis transcricionais de quinze isoformas de GST a fim de identificar isoformas possivelmente envolvidas na detoxificação de contaminantes ambientais como a microcistina-LR (MC-LR) em Danio rerio. A técnica de PCR em tempo real (RT-qPCR) foi utilizada para avaliação dos níveis transcricionais, permitindo análise das GST em diferentes órgãos, abundância e a ativação/repressão das isoformas de GST pela exposição à MC-LR. Foram avaliados os possíveis efeitos causados em brânquia e fígado após exposição por 24 hs às concentrações de 5 µg.L-1 e 50 µg.L-1 de MC-LR. Baseado nos scores de estabilidade para oito genes normalizadores, foram selecionados glicose-6-fosfato desidrogenase (g6pdh), β-actina1 e beta-2-microglobulina (b2m); b2m, alfa-tubulina 1 (tuba) e β- actin1; e tuba, b2m e g6pdh, para normalização dos níveis trancricionais de GST para distribuição órgão-específica, abundância e efeito da MC-LR em brânquia e fígado, respectivamente. A avaliação transcricional da distribuição órgão-específica revelou níveis significativos de gstal e gstk1.1 no fígado; gstp1 e gstp2 em brânquia; mgst3a, gstr1, gstm2, gstm33, gstp1, gstp2 e gstk1.1 no intestino; gstm2, gstm3 e gstal no olho e gstt1a e gsta2.1 no cérebro. Considerando os níveis de transcritos para um dado órgão, gstk1.1, gstal, gstp1 e gstt2 foram mais abundantes nos órgãos de detoxificação, tais como o fígado, brânquias e intestino, enquanto gstt1a e gsta2.1 foram mais abundantes no rim. Em brânquia, gsta2.1 e gstt1b foram reprimidas por 5 µg.L-1 de MC-LR e mgst1.1 foi reprimida em 50 µg.L-1 de MC-LR. No fígado, as isoformas gst2.2 e gstp2 foram reprimidas em ambas as concentrações, gstal foi reprimida em 5 µg.L-1, e gstt1a e gstk1.1 foram reprimidas em 50 µg.L-1 de MC-LR. As isoformas gstal, gstr1, gstp1, mgst3a, gstm1, gstm2 e gstm3 não foram alteradas pela exposição a MC-LR. Os resultados obtidos fornecem informações para a escolha de isoformas específicas de GST possivelmente envolvidas na detoxificação/toxicidade de MC-LR, a serem melhores caracterizadas ao nível protéico e também contribui para a escolha de genes normalizadores a serem utilizados em outros estudos da mesma natureza
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Structural changes in waste for zeolites synthesis are subject of many studies carried out in the synthesis of molecular sieves. These materials are named molecular sieves because they have well defined pore sizes and they have the capacity of select molecules by its size. In this work, it was studied the synthesis processes of two types of molecular sieves: pillared acid clays using as starting material one natural montmorillonite clay and the synthesis of zeolites from a silico-aluminous residue. This residue is a byproduct of the extraction of lithium -spodumene. The preparation of pillared acid clays was performed in two steps: 1° acid treatment of clay samples (time and temperature studies) and 2°pilarization of them with Al13 (Keggin ion). The temperature and acid concentration affect the removal of cations in the structure and porosity of the material obtained. The analysis of X-ray diffraction (XRD) and infrared spectroscopy (IR), showed that increasing the severity of the acid treatment compromises the structural material. Also the pore size distribution is approximately uniform. Despite presenting a structural disorganization, the samples were pillared. As evidenced by XRD increasing the basal spacing, specific area and uniform porosity by adsorption of N2. Regarding the microporous molecular sieves were synthesized zeolites A and NaP1 from a silico-aluminous residue, a byproduct of extracting lithium. The temperature and time of agitation during the synthesis were the most important factors for obtaining zeolite A. The aging of the gel and the highest crystallization time promoted the formation of zeolite NaP1 using a Si / Al ratio = 3.2
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BACKGROUND Anaplasma phagocytophilum infects a wide variety of hosts and causes granulocytic anaplasmosis in humans, horses and dogs and tick-borne fever in ruminants. Infection with A. phagocytophilum results in the modification of host gene expression and immune response. The objective of this research was to characterize gene expression in pigs (Sus scrofa) naturally and experimentally infected with A. phagocytophilum trying to identify mechanisms that help to explain low infection prevalence in this species. RESULTS For gene expression analysis in naturally infected pigs, microarray hybridization was used. The expression of differentially expressed immune response genes was analyzed by real-time RT-PCR in naturally and experimentally infected pigs. Results suggested that A. phagocytophilum infection affected cytoskeleton rearrangement and increased both innate and adaptive immune responses by up regulation of interleukin 1 receptor accessory protein-like 1 (IL1RAPL1), T-cell receptor alpha chain (TCR-alpha), thrombospondin 4 (TSP-4) and Gap junction protein alpha 1 (GJA1) genes. Higher serum levels of IL-1 beta, IL-8 and TNF-alpha in infected pigs when compared to controls supported data obtained at the mRNA level. CONCLUSIONS These results suggested that pigs are susceptible to A. phagocytophilum but control infection, particularly through activation of innate immune responses, phagocytosis and autophagy. This fact may account for the low infection prevalence detected in pigs in some regions and thus their low or no impact as a reservoir host for this pathogen. These results advanced our understanding of the molecular mechanisms at the host-pathogen interface and suggested a role for newly reported genes in the protection of pigs against A. phagocytophilum.
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Aggretin, a potent platelet activator, was isolated from Calloselasma rhodostoma venom, and 30-amino acid N-terminal sequences of both subunits were determined. Aggretin belongs to the heterodimeric snake C-type lectin family and is thought to activate platelets by binding to platelet glycoprotein alpha(2)beta(1). We now show that binding to glycoprotein (GP) Ib is also required. Aggretin-induced platelet activation was inhibited by a monoclonal antibody to GPIb as well as by antibodies to alpha(2)beta(1). Binding of both of these platelet receptors to aggretin was confirmed by affinity chromatography. No binding of other major platelet membrane glycoproteins, in particular GPVI, to aggretin was detected. Aggretin also activates platelets from Fc receptor gamma chain (Fcgamma)-deficient mice to a greater extent than those from normal control mice, showing that it does not use the GPVI/Fcgamma pathway. Platelets from Fcgamma-deficient mice expressed fibrinogen receptors normally in response to collagen, although they did not aggregate, indicating that these platelets may partly compensate via other receptors including alpha(2)beta(1) or GPIb for the lack of the Fcgamma pathway. Signaling by aggretin involves a dose-dependent lag phase followed by rapid tyrosine phosphorylation of a number of proteins. Among these are p72(SYK), p125(FAK), and PLCgamma2, whereas, in comparison with collagen and convulxin, the Fcgamma subunit neither is phosphorylated nor coprecipitates with p72(SYK). This supports an independent, GPIb- and integrin-based pathway for activation of p72(SYK) not involving the Fcgamma receptor.
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Homopolymers of alpha 2,8-linked N-acetylneuraminic acid [poly(alpha 2,8-Neu5Ac)] of the neural cell adhesion molecule NCAM have been shown to be temporally expressed during lung development and represent a marker for small cell lung carcinoma. We report the presence of a further polysialic acid in lung that consists of oligo/polymers of alpha 2,8-linked deaminoneuraminic acid residues [poly (alpha 2,8-KDN)], as detected with a monoclonal antibody in conjunction with a specific sialidase. Although the various cell types forming the bronchi, alveolar septs, and blood vessels were positive for poly (alpha 2,8-KDN) by immunohistochemistry, this polysialic acid was found on a single 150-kDa glycoprotein by immunoblot analysis. The poly(alpha 2,8-KDN)-bearing glycoprotein was not related to an NCAM protein based on immunochemical criteria. The expression of the poly (alpha 2,8-KDN) was developmentally regulated as evidenced by its gradual disappearance in the rat lung parenchyma commencing 1 week after birth. In adult lung the blood vessel endothelia and the smooth muscle fibers of both blood vessels and bronchi were positive but not the bronchial and alveolar epithelium. The poly (alpha 2,8-KDN)-bearing 150-kDa glycoprotein became reexpressed in various histological types of lung carcinomas and cell lines derived from them and represents a new oncodevelopmental antigen in lung.