RESUMEN
Exposure to ambient particulate matter (PM) increases mortality and morbidity due to respiratory and cardiovascular diseases. The aim of this study was to assess the effect of standardized urban dust (UD) on phagocytosis and autophagy in a monocyte-macrophage cell line (THP-1 cells). The cells were grown for 24 h in the medium supplemented with 200 µg·mL-1 coarse carbon black (CB) or UD. In some experiments glutathione (GSH) was depleted in THP-1 cells by buthionine sulfoximine. The cells were double stained with green latex beads (phagocytosis) and with red autophagy marker (LC3) and were evaluated in a flow cytometer. In naïve THP-1 cells, about 61% of them were classified as "negative", while 39% were classified as "double-positive". Both GSH depletion and UD treatment produced three distinct subpopulations of cells on bivariate scatterplots. A new subpopulation of cells (about 24% of the total number) appeared, with a lower autophagy and phagocytosis, but with a higher autophagy/phagocytosis ratio, when compared to highly positive cells. CB affected, to some extent, phagocytosis without a substantial effect on autophagy. In conclusion, the research on distinct pathways of immune cell activation may be relevant to the diagnostics and therapy of PM-induced pneumotoxicity, inflammation, and tumorigenesis.
Asunto(s)
Autofagia , Polvo , Proteínas Asociadas a Microtúbulos/análisis , Fagocitosis , Humanos , Células THP-1RESUMEN
Chronic exposure to cigarette smoke (CS) causes structural and functional changes in the respiratory tract. It is a major risk factor for cardiovascular and systemic pulmonary diseases. The aim of this study was to investigate the effect of acute CS exposure (2 h) on oxidative stress, heat shock protein 70 (HSP70) expression, autophagy (LC3 expression), and oxidative stress (DCF fluorescence) in human alveolar epithelial cell line A549. Cell culture medium was conditioned with CS using commercial cigarettes, and A549 cells were grown in modified media for 2 h. In some experiments, A549 cells were pretreated with 100 µM of L-buthionine-sulfoximine (BSO) for 24 h to induce glutathione (GSH) depletion. In the cells grown in CS-conditioned medium, GSH was depleted by more than 30%, and reactive oxygen species were increased. Moreover, there was a considerable overexpression of HSP70 and a substantial accumulation of LC3. Similar changes were found when the cells were pretreated with BSO. We conclude that the short-term exposure of epithelial cells to CS increases oxidative stress that entails enhanced autophagy activity.
Asunto(s)
Células Epiteliales Alveolares , Autofagia , Estrés Oxidativo , Contaminación por Humo de Tabaco/efectos adversos , Células A549 , Células Epiteliales Alveolares/efectos de los fármacos , Autofagia/efectos de los fármacos , Fumar Cigarrillos/efectos adversos , Humanos , Estrés Oxidativo/efectos de los fármacosRESUMEN
Exposure to urban airborne particulate matter (PM) associates with adverse health effects, but the exact mechanisms remain unclear. In this study, we focused on cytotoxicity (MTT), oxidative stress (DCF/FC), DNA damage (PI/FC), necrosis/apoptosis (FC), and autophagy (LC3 expression; WB/FC) triggered by urban dust (UD) in naïve human alveolar epithelial A549 cells and in the cells with reduced glutathione (GSH). The A549 cells were grown in F12K/FCS media supplemented with coarse carbon black (CB; Huber990; 260 nm diameter; 200 µg·ml-1) or urban dust (UD; Standard Reference Materials; 200 µg·ml-1) for 24 h. To deplete intracellular glutathione (GSH), l-buthionine-(S,R)-sulfoximine (BSO; 100 mM; 24 h) was used. Pre-treatment with BSO depleted the cellular GSH by about 30%. A similar effect was noticed after UD. The CB was without any effects on the parameters tested, except for LC3 expression (autophagy) which increased by about twofold. However, UD decreased cell viability by about 27%, decreased cell proliferation in BSO pre-treated cells, increased ROS production, and increased both Hsp70 and LC3 proteins by about twofold, but most changes were unrelated to ROS-mediated GSH depletion. We conclude that urban dust-induced oxidative stress is important in PM toxicity, but other as yet unrecognized mechanisms are also involved.
Asunto(s)
Células Epiteliales Alveolares , Autofagia , Polvo , Estrés Oxidativo , Material Particulado , Células A549 , Células Epiteliales Alveolares/efectos de los fármacos , Autofagia/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Glutatión/metabolismo , Humanos , Estrés Oxidativo/efectos de los fármacos , Material Particulado/toxicidad , Especies Reactivas de OxígenoRESUMEN
In 2011-2013 1588 samples of dogs' blood were examined for dirofilariosis using Knott method, as well as the Kingston and Morton method. The species of microfilariae was determined on the basis of morphometric characteristics. Samples were also examined using the Canine Heartworm Antigen Test. Positive samples were examined using a multiplex PCR assay for species confirmation. Microfilariae belonging to the species D. repens were found in the blood samples of dogs from all the provinces of Poland. The mean prevalence of this species observed in Poland was 11.7%. The range of intensity of infection was counted using the number of microfilariae found in 60 microl of blood amounted to between 1 and 158, and the mean intensity was 18 microfilariae. Microfilariae and antigens of D. immitis were not found in any examined blood samples.
Asunto(s)
Dirofilaria repens/aislamiento & purificación , Dirofilariasis/parasitología , Enfermedades de los Perros/parasitología , Animales , Enfermedades de los Perros/epidemiología , Perros , Polonia/epidemiología , PrevalenciaRESUMEN
OBJECTIVE: ISL1 is a pioneer transcription factor that plays important roles in cell lineage specification and differentiation, by programming the epigenome and recruiting additional regulatory factors. The aim of this study is to determine whether the human breastmilk contains ISL1-positive stem cells, and, if so, to describe the subcellular localization of ISL1. MATERIALS AND METHODS: Breast milk was obtained from fourteen healthy females during the first 2-6 months of lactation. Cell morphology was examined in the breast milk with the automatic ThinPrep® processor (Hologic® Inc.) in commercial Cytological ThinPrep® solution (Hologic® Inc.), followed by standard immunohistochemical staining of ISL1. RESULTS: ISL1 had a granular diffuse cytoplasmic localization, with varying intensity of staining in both single and grouped cells. Nuclear staining was also present, as was staining of intracellular and extracellular vesicles with ISL1 antibody. CONCLUSIONS: These preliminary results suggest that ISL1 could distinguish a readily available source of putative stem cells in human breast milk. These stem cells may complete the network created between the mother and the newborn during gestation, thereby improving the efficiency of programming and reprogramming postnatal events.
Asunto(s)
Leche Humana , Factores de Transcripción , Femenino , Humanos , Recién Nacido , Diferenciación Celular , Regulación de la Expresión Génica , Miocitos Cardíacos/metabolismo , Factores de Transcripción/genéticaRESUMEN
Asworthius sidemi Schulz, 1933 is a blood sucking gastrointestinal nematode, primarily typical for Asiatic deer. It was found for the first time in Poland in European bison in 1997. To estimate the level of invasion of A. sidemi and histopathological changes connected with the presence of the parasite in the years 2004-2007 parasitological and histopathological examinations of 54 European bison from Bialowieza Forest were carried out. Parasitological examination was carried out by the sedimentation method and A. sidemi were diagnosed under a binocular microscope. Samples for histological examination were collected from the abomasum and duodenum walls as well as from regional lymph nodes. Tissue samples were then fixed with 10% buffered formalin, embedded in paraffin, cut in to 5 microm thick sections and stained with hematoxylin and eosin (H&E). Parasitological examinations showed the presence of fourth stage larvae and juvenile forms of A. sidemi. The maximal intensity of invasion rose systematically from 4470 A. sidemi nematodes in 2004/2005 to 44310 in 2006/2007. Histopathological examinations showed infiltrations of inflammatory cells in the walls of abomasa and duodena at various levels of intensity (mainly lymphoid cells and eosinophils), hyperemiae, oedemae and lesions of mucosa and proliferation of lymphatic follicles. In individual cases of dysplasia of epithelial cells, atrophy or hyperplasia of glands and the presence of parasites in the lumen or walls of the abomasum/duodenum were observed. In one case, parasitic nodules were found. In regional lymph nodes proliferation of lymphatic follicles, presence of eosinophils and desolation of reproduction centers were observed. Intensification of histopathological changes was connected to a considerable degree with the developmental stage of A. sidemi as shown by parasitological examination.
Asunto(s)
Bison , Enfermedades Gastrointestinales/veterinaria , Tracto Gastrointestinal/parasitología , Trichostrongyloidea/clasificación , Tricostrongiloidiasis/veterinaria , Animales , Femenino , Enfermedades Gastrointestinales/parasitología , Enfermedades Gastrointestinales/patología , Tracto Gastrointestinal/patología , Masculino , Tricostrongiloidiasis/parasitología , Tricostrongiloidiasis/patologíaRESUMEN
BACKGROUND: Dogs with multicentric lymphoma are treated with various cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP)-based chemotherapy protocols with variable success. OBJECTIVES: To describe the progression-free survival (PFS) time and overall survival time (OST) of dogs with T-cell lymphoma or hypercalcemic lymphoma treated with L-asparaginase and mechlorethamine, vincristine, prednisone, procarbazine (MOPP). ANIMALS: Fifty dogs with T-cell lymphoma, hypercalcemic lymphoma, or both treated at 3 referral veterinary hospitals. METHODS: Retrospective study. Case were selected based on histologic or cytologic diagnosis of lymphoma; presence of the T-cell phenotype, presence of hypercalcemia or both; and absence of previous chemotherapy. The T-cell phenotype was determined by flow cytometry, immunocytochemistry, immunohistochemistry, or polymerase chain reaction of antigen receptor rearrangement. RESULTS: The overall response rate was 98% (78% complete response, 20% partial response). The median PFS for the entire study population was 189 days with 25% PFS at 939 days. The median OST for the entire study population was 270 days with 25% surviving 939 days. Twenty percent of the dogs required hospitalization for treatment related complications. CONCLUSIONS AND CLINICAL IMPORTANCE: L-Asp/MOPP chemotherapy might result in longer PFS and OST for dogs with multicentric T-cell lymphoma, dogs with hypercalcemic lymphoma or both, than achieved with CHOP.
Asunto(s)
Antineoplásicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Asparaginasa/uso terapéutico , Enfermedades de los Perros/tratamiento farmacológico , Linfoma/veterinaria , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Asparaginasa/administración & dosificación , Perros , Femenino , Linfoma/tratamiento farmacológico , Masculino , Mecloretamina/administración & dosificación , Mecloretamina/uso terapéutico , Prednisona/administración & dosificación , Prednisona/uso terapéutico , Procarbazina/administración & dosificación , Procarbazina/uso terapéutico , Estudios Retrospectivos , Vincristina/administración & dosificación , Vincristina/uso terapéuticoRESUMEN
Between 2003-2007, abomasa of 91 European bison (Bison bonasus), 4 red deer (Cervus elaphus) and 2 roe deer (Capreolus capreolus) shot in the Bialowieza Primeval Forest (Poland) were examined for worms presence. All the animals examined were infected with nematodes A. sidemi with an exception of one bison, that was shot in year 2003. There was much higher average intensity of invasion in bison (5529), than in red deer (85) and in roe deer (1837). The animals were shot in a period from December to March, and the nematodes found in them were fourth stage larvae and immature adult specimens. In the following years of examinations, a gradual increase in average intensity of infection was observed. In 2007, it reached in bison 10814 nematodes. Maximum intensity of invasion was found in this year as well and it reached 44310 nematodes in one bison. Pathological changes such as an oedema, hyperaemia and effusion in the abomasum and duodenum mucosa were most clearly seen in the calves that were highly infected. These changes probably lead to chronic diarrhoea, deterioration and deaths of young animals.
Asunto(s)
Bison , Ciervos , Nematodos/aislamiento & purificación , Tricostrongiloidiasis/veterinaria , Animales , Polonia/epidemiología , Factores de Tiempo , Tricostrongiloidiasis/epidemiología , Tricostrongiloidiasis/parasitologíaRESUMEN
The design of new and efficient chelators that can remove aluminium(iii), a metal with increasing recognition as a potential toxic agent, from biological systems is an area of high therapeutic relevance. In the present paper, we present an extensive computational study of a new promising type of these chelators based on mimosine containing peptides. The reason to choose mimosine is that the sidechain of this residue is similar to deferiprone, a ligand known to tightly interact with highly-valent metals, and in particular with Al(iii). In this article we analyze systematically, using a combination of methods that include QM/MM MD simulations, how the size and sequence of the polypeptides can alter the fundamental binding patterns to aluminum, in comparison with the binding to deferiprone. Particular attention is given towards the identification of the smallest peptide that interacts efficiently with aluminum, since polypeptide size is a fundamental factor to allow a given polypeptide to efficiently cross the cell membrane. The results indicate that the longest peptides, with 8 or 9 amino acids, show no difficulties interacting with Al(iii) in an optimum arrangement. By contrast, when the peptide contains five or six amino acids Al(iii) is pentacoordinated, reducing the stability of the resultant complex. In summary, our study demonstrates that the mimosine containing peptides can efficiently coordinate highly valent metals such as Al(iii), with a subtle dependence of the binding on the specific chain-lengths of the polypeptide. We believe that the present study sheds light on the adequacy of this new type of chelator towards aluminum binding.
RESUMEN
ADP plays a critical role in modulating thrombosis and hemostasis. ADP initiates platelet aggregation by simultaneous activation of two G protein-coupled receptors, P2Y1 and P2Y12. Activation of P2Y1 activates phospholipase C and triggers shape change, while P2Y12 couples to Gi to reduce adenylyl cyclase activity. P2Y12 has been shown to be the target of the thienopyridine drugs, ticlopidine and clopidogrel. Recently, we cloned a human orphan receptor, SP1999, highly expressed in brain and platelets, which responded to ADP and had a pharmacological profile similar to that of P2Y12. To determine whether SP1999 is P2Y12, we generated SP1999-null mice. These mice appear normal, but they exhibit highly prolonged bleeding times, and their platelets aggregate poorly in responses to ADP and display a reduced sensitivity to thrombin and collagen. These platelets retain normal shape change and calcium flux in response to ADP but fail to inhibit adenylyl cyclase. In addition, oral clopidogrel does not inhibit aggregation responses to ADP in these mice. These results demonstrate that SP1999 is indeed the elusive receptor, P2Y12. Identification of the target receptor of the thienopyridine drugs affords us a better understanding of platelet function and provides tools that may lead to the discovery of more effective antithrombotic therapies.
Asunto(s)
Plaquetas/efectos de los fármacos , Fibrinolíticos/farmacología , Proteínas de la Membrana , Antagonistas del Receptor Purinérgico P2 , Ticlopidina/farmacología , Adenosina Difosfato/farmacología , Adenilil Ciclasas/metabolismo , Animales , Tiempo de Sangría , Coagulación Sanguínea , Plaquetas/metabolismo , Células Cultivadas , Clopidogrel , Marcación de Gen , Cinética , Ratones , Ratones Noqueados , Agregación Plaquetaria/efectos de los fármacos , Receptores Purinérgicos P2/genética , Receptores Purinérgicos P2Y12 , Ticlopidina/análogos & derivadosRESUMEN
In 1953, during the building restoration of San Michele church (Bono, Sardinia, 16th-19th Century), a high number of disarticulated skeletons were recovered. From a group of 412 hip bones, two of these, affected by several pathological lesions, were analysed. The two coxal bones can be referred to the same individual, an adult man. A multi-analytical study, started with the purpose of investigating the bone pathology, was extended to characterize the mineral components of a large representative set of bones from the same ossuary, all attributed to adult men who lived in the region four-two centuries ago. A quantitative ICP-AES analysis for Ca, Fe, Mg, Mn, Na, Pb and Zn was executed, and a chemometric investigation on the results was performed. This approach gave evidence of the effects of diagenesis, allowed some hypothesis of the incidence of the known dietary habits on bone composition, and completely differentiated the pathological bones from those of a normal population on the basis of the mineral composition. Moreover, porosity, crystallinity and FT-IR analysis were conducted on both non- and pathological sample.
Asunto(s)
Huesos/química , Minerales/análisis , Adulto , Huesos/patología , Humanos , Masculino , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
The synthesis of 5-hydroxy-2-(hydroxymethyl)pyridin-4(1H)-one (P1) is presented, together with the evaluation of its coordination ability towards Fe(3+), studied by a combination of chemical, computational, and animal approaches. The use of complementary analytical techniques has allowed us to give evidence of the tautomeric changes of P1 as a function of pH, and to determine their influence on the coordinating ability of P1 towards Fe(3+). The pFe(3+) value 22.0 of P1-iron complexes is noticeably higher than that of deferiprone (20.6), one of the three clinical chelating agents in therapeutic use for iron overload diseases. This is due on one side to the tautomeric change to the catechol form, and on the other to the lower protonation constant of the OH group. Bio-distribution studies on mice allowed us to confirm in vivo the efficacy of P1. Furthermore the coordinating ability toward Al(3+), Cu(2+) and Zn(2+) has been studied to evaluate the possible use of P1 against a second toxic metal ion (Al(3+)), and to envisage its potential influence on the homeostatic equilibria of essential metal ions. The chelating ability of P1 toward these ions, not higher than that of the corresponding deferiprone, contributes to render P1 a more selective iron chelator.
Asunto(s)
Quelantes del Hierro/química , Quelantes del Hierro/síntesis química , Hierro/química , Piridinas/química , Piridinas/síntesis química , Piridonas/química , Piridonas/síntesis química , Animales , Técnicas de Química Sintética , Cristalografía por Rayos X , Femenino , Interacciones Hidrofóbicas e Hidrofílicas , Quelantes del Hierro/farmacocinética , Ratones , Modelos Moleculares , Conformación Molecular , Protones , Piridinas/farmacocinética , Piridonas/farmacocinética , Distribución TisularRESUMEN
Sixty-four dogs were treated with single-agent doxorubicin (DOX) for presumptive cardiac hemangiosarcoma (cHSA). The objective response rate (CR + PR) was 41%, and the biologic response rate (CR + PR + SD), or clinical benefit, was 68%. The median progression-free survival (PFS) for treated dogs was 66 days. The median survival time (MST) for this group was 116 days and was significantly improved compared to a MST of 12 days for untreated control dogs (P = 0.0001). Biologic response was significantly associated with improved PFS (P < 0.0001) and OS (P < 0.0001). Univariate analysis identified larger tumour size as a variable negatively associated with PFS. The high rate of clinical benefit and improved MST suggest that DOX has activity in canine cHSA.
Asunto(s)
Antibióticos Antineoplásicos/uso terapéutico , Enfermedades de los Perros/tratamiento farmacológico , Doxorrubicina/uso terapéutico , Neoplasias Cardíacas/veterinaria , Hemangiosarcoma/veterinaria , Animales , Estudios de Casos y Controles , Perros , Femenino , Neoplasias Cardíacas/tratamiento farmacológico , Hemangiosarcoma/tratamiento farmacológico , Masculino , Estudios Retrospectivos , Análisis de SupervivenciaRESUMEN
Hemokinin-1 (HK-1) is a recently described mouse tachykinin peptide whose biological functions are not fully understood. To date, a unique receptor for HK-1 has not been identified. Recent studies suggest HK-1 may have a role in immunological functions, but there has been little characterization of HK-1's effects in the central nervous system (CNS). In the present studies, we confirm that HK-1 is an endogenous agonist at all of the known tachykinin receptors, and is selective for the NK1 receptor over the NK2 and NK3 subtypes. CHO cells transfected with the human NK1 receptor released intracellular calcium in response to HK-1. In addition, HK-1 competed with substance P (SP) for binding to mouse NK1 and human NK1 receptors. In vivo central administration of HK-1 to gerbils and mice induced foot-tapping and scratching behaviors, respectively, similar to those observed following central administration of SP or the NK1 receptor agonist, GR-73632. Furthermore, these behavioral effects were blocked by the selective NK1 receptor antagonist, MK-869. Finally, a comprehensive expression analysis of HK-1 demonstrated that HK-1 mRNA is much more broadly expressed than previously reported with expression observed in many brain regions. Together these data demonstrate that HK-1 is a functional agonist at NK1 receptors and suggest that HK-1 may function both centrally and peripherally.
Asunto(s)
Conducta Animal/efectos de los fármacos , Precursores de Proteínas/administración & dosificación , Receptores de Neuroquinina-1/agonistas , Sustancia P/farmacología , Taquicininas/administración & dosificación , Animales , Conducta Animal/fisiología , Células CHO , Cricetinae , Relación Dosis-Respuesta a Droga , Femenino , Gerbillinae , Humanos , Masculino , Ratones , Antagonistas del Receptor de Neuroquinina-1 , Precursores de Proteínas/biosíntesis , Receptores de Neuroquinina-1/metabolismo , Sustancia P/biosíntesis , Taquicininas/biosíntesisRESUMEN
The serotonin receptor subtype 6, which raises intracellular cyclic AMP via stimulatory G-proteins, has recently been cloned and characterized. To determine the distribution of serotonin subtype 6 messenger RNA, in situ hybridization was performed in coronal sections of rat brain. 35S-labeled riboprobe, complementary to the 5' non-coding region of the serotonin subtype 6 messenger RNA, and a 33P-labeled riboprobe complementary to its 3' non-coding region, were used for hybridization. Serotonin subtype 6 receptor message was found in serotonin projection fields, rather than regions of serotonin-containing cell bodies, suggesting that the receptor is mainly postsynaptic. Hybridization signal was highest in olfactory tubercle, as well as prominent in the striatum, nucleus accumbens, dentate gyrus, and CA1, CA2 and CA3 of the hippocampus. Less intense hybridization was observed in cerebellum, some diencephalic nuclei, the amygdala, and layers 2, 3, 4 and 6 of the cortex. This pattern of hybridization was observed with both probes, but not when sense transcripts were used. Because the serotonin subtype 6 receptor has a high affinity for the atypical antipsychotic clozapine, and because striatum and nucleus accumbens are proposed sites of antipsychotic drug effects, the possibility is raised that this receptor may play an important role in mediating the effects of the atypical antipsychotic agents.
Asunto(s)
Encéfalo/fisiología , ARN Mensajero/genética , Receptores de Serotonina/fisiología , Animales , Autorradiografía , Ganglios Basales , Corteza Cerebral/fisiología , Hibridación in Situ , Masculino , Ratas , Ratas Sprague-Dawley , Receptores de Serotonina/clasificaciónRESUMEN
Current treatment of Alzheimer's Disease (AD) requires acetylcholinesterase inhibition to increase acetylcholine (ACh) concentrations in the synaptic cleft. Another mechanism by which ACh levels can be increased is blockade of presynaptic M2 muscarinic autoreceptors that regulate ACh release. An antagonist designed for this purpose must be highly selective for M2 receptors to avoid blocking postsynaptic M1 receptors, which mediate the cognitive effects of ACh. Structure-activity studies of substituted methylpiperadines led to the synthesis of 4-[4-[1(S)-[4-[(1,3-benzodioxol-5-yl)sulfonyl]phenyl]ethyl]-3(R)-methyl-1-piperazinyl]-4-methyl-1-(propylsulfonyl)piperidine. This compound, SCH 72788, binds to cloned human M2 receptors expressed in CHO cells with an affinity of 0.5 nM, and its affinity at M1 receptors is 84-fold lower. SCH 72788 is a functional M2 antagonist that competitively inhibits the ability of the agonist oxotremorine-M to inhibit adenylyl cyclase activity. In an in vivo microdialysis paradigm, SCH 72788 increases ACh release from the striatum of conscious rats. The compound is also active in a rodent model of cognition, the young rat passive avoidance response paradigm. The effects of SCH 72788 suggest that M2 receptor antagonists may be useful for treating the cognitive decline observed in AD and other dementias.
Asunto(s)
Acetilcolina/metabolismo , Antagonistas Muscarínicos/farmacología , Piperazinas/farmacología , Piperidinas/farmacología , Receptores Muscarínicos/metabolismo , Sinapsis/efectos de los fármacos , Adenilil Ciclasas/metabolismo , Enfermedad de Alzheimer/tratamiento farmacológico , Animales , Células CHO , Cricetinae , Relación Dosis-Respuesta a Droga , Humanos , Cinética , Aprendizaje/efectos de los fármacos , Memoria/efectos de los fármacos , Estructura Molecular , Agonistas Muscarínicos/farmacología , Antagonistas Muscarínicos/síntesis química , Antagonistas Muscarínicos/metabolismo , Antagonistas Muscarínicos/uso terapéutico , Oxotremorina/farmacología , Piperazinas/síntesis química , Piperazinas/metabolismo , Piperazinas/uso terapéutico , Piperidinas/síntesis química , Piperidinas/metabolismo , Piperidinas/uso terapéutico , Ensayo de Unión Radioligante , Ratas , Receptor Muscarínico M2 , Transducción de Señal/fisiología , Sinapsis/metabolismoRESUMEN
As a decrease in cholinergic neurons has been observed in Alzheimer's Disease (AD), therapeutic approaches to AD include inhibition of acetylcholinesterase to increase acetylcholine levels. Evidence suggests that acetylcholine release in the CNS is modulated by negative feedback via presynaptic M2 receptors, blockade of which should provide another means of increasing acetylcholine release. Structure-activity studies of [4-(phenylsulfonyl)phenyl]methylpiperazines led to the synthesis of 4-cyclohexyl-alpha-[4-[[4-methoxyphenyl]sulfinyl]-phenyl]-1-piperazin eacetonitrile. This compound, SCH 57790, binds to cloned human M2 receptors expressed in CHO cells with an affinity of 2.78 nM; the affinity at M1 receptors is 40-fold lower. SCH 57790 is an antagonist at M2 receptors expressed in CHO cells, as the compound blocks the inhibition of adenylyl cyclase activity mediated by the muscarinic agonist oxotremorine. This compound should be useful in assessing the potential of M2 receptor blockade for enhancement of cognition.
Asunto(s)
Antagonistas Muscarínicos/farmacología , Piperazinas/farmacología , Receptores Muscarínicos/fisiología , Acetilcolina/metabolismo , Adenilil Ciclasas/metabolismo , Enfermedad de Alzheimer/tratamiento farmacológico , Animales , Sitios de Unión , Células CHO , Colforsina/antagonistas & inhibidores , Colforsina/farmacología , Cricetinae , AMP Cíclico/metabolismo , Humanos , Agonistas Muscarínicos/farmacología , Antagonistas Muscarínicos/química , Antagonistas Muscarínicos/metabolismo , Antagonistas Muscarínicos/uso terapéutico , Oxotremorina/farmacología , Piperazinas/química , Piperazinas/metabolismo , Quinuclidinil Bencilato/metabolismo , Receptor Muscarínico M2 , Receptores Muscarínicos/metabolismo , TransfecciónRESUMEN
Alzheimer's disease (AD) is a neurodegenerative disease characterized by cognitive impairment and personality changes. The development of drugs for the treatment of the cognitive deficits of AD has focused on agents which counteract loss in cholinergic activity. Although symptoms of AD have been successfully treated with acetylcholinesterase inhibitors (tacrine, donepezil. rivastigmine, galanthamine), limited success has been achieved with direct M1 agonists, probably due to their lack of selectivity versus other muscarinic receptor subtypes. Muscarinic M2 antagonists have been reported to increase synaptic levels of acetylcholine after oral administration to rats (e.g. BIBN-99, SCH-57790), but their selectivity versus other muscarinic receptor subtypes is modest. Exploration of a series of piperidinylpiperidines has yielded the potent and selective M2 antagonist SCH-217443. This antagonist has excellent bioavailability in rats and dogs and shows activity in a rat model of cognition.
Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Agonistas Muscarínicos/uso terapéutico , Antagonistas Muscarínicos/uso terapéutico , Animales , Humanos , Agonistas Muscarínicos/química , Antagonistas Muscarínicos/química , Relación Estructura-ActividadRESUMEN
Acquired amegakaryocytic thrombocytopenla was diagnosed in four dogs. Initial platelet counts in all four dogs were less than 50,000 x 10(9)/litre and initial bone marrow examinations revealed megakaryocytic hypoplasia with minimal changes in the erythroid and myeloid cell lines. Two dogs had evidence of idiopathic immune-mediated disease and two dogs had evidence of associated infectious disease. One dog had a positive antibody titre to Borrella burgdorferi, and one dog had positive titres to both Ehrlichia canis and B. burgdorferi. Treatment consisted of prednisone and cyclophosphamide for the dogs with presumptive immune-mediated disease, and prednisone and tetracycline for the dogs with positive antibody titres to the Infectious organisms. Both dogs with evidence of associated infectious disease responded to treatment. A postmortem examination did not reveal the underlying aetiology in the two dogs with presumptive idiopathic immune-mediated disease.
Asunto(s)
Enfermedades de los Perros/etiología , Púrpura Trombocitopénica Idiopática/veterinaria , Trombocitopenia/veterinaria , Animales , Borrelia burgdorferi/efectos de los fármacos , Borrelia burgdorferi/crecimiento & desarrollo , Enfermedades de los Perros/tratamiento farmacológico , Enfermedades de los Perros/inmunología , Enfermedades de los Perros/microbiología , Perros , Ehrlichia canis/efectos de los fármacos , Ehrlichia canis/crecimiento & desarrollo , Ehrlichiosis/complicaciones , Ehrlichiosis/veterinaria , Femenino , Enfermedad de Lyme/complicaciones , Enfermedad de Lyme/veterinaria , Masculino , Púrpura Trombocitopénica Idiopática/tratamiento farmacológico , Púrpura Trombocitopénica Idiopática/inmunología , Púrpura Trombocitopénica Idiopática/microbiología , Trombocitopenia/tratamiento farmacológico , Trombocitopenia/inmunología , Trombocitopenia/microbiología , Resultado del TratamientoRESUMEN
Parasitological autopsy of 31 european bison , 9 red-deer and 3 roe-deer was made in Bialowieza Forest in the period 1983-1988. Together 20 species of nematodes were found, from them as much as 18 in bison , 6 in red-deer and 8 in roe-deer . The highest intensity and 100% of extensity was shown by nematodes from subfamily Ostertagiinae. Four species of this subfamily (O. leptospicularis, O. kolchida, S. boehmi i S. mathevossiani) have been permanently adapted by bison from cervids, however two species of nematodes typical for bison and cattle (O. ostertagii and O. lyrata) have not been adopted by deer . Besides, bison adopted from deer the following species of nematodes: T. capricola, C. pectinata, N. roscidus, N. europaeus and from moose N. alcidis. Bison gave to red-deer only C. bilobata, and roe-deer have not adopted any nematodes from bison . B. trigonocephalum and S. dagestanica found in roe-deer are in Poland typical parasites of moose .