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1.
Biosens Bioelectron ; 252: 116146, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38417286

RESUMEN

Staphylococcus aureus contamination in food supplements poses substantial challenges to public health and large-scale production but the sensitive detection in a timely manner remains a bottleneck. Drawing inspiration from the sea hedgehog, gold nanostars (AuNSs) were leveraged to design an ultrasensitive surface-enhanced Raman scattering (SERS) biosensor for the determination of Staphylococcus aureus in food supplements. Besides the surface enhancement furnished by the AuNSs, Raman reporter molecules and specific aptamers sequentially self-assembled onto these AuNSs to construct the "three-in-one" SERS biosensor probe for label-based quantitation of Staphylococcus aureus. Following incubation with contaminated health product samples, the gold nanostars@Raman reporter-aptamer specifically recognize and assemble around Staphylococcus aureus cells, forming a distinctive sea hedgehog structure. This unique configuration results in an amplified Raman signal at 1338 cm-1 and an enhancement factor of up to 6.71 × 107. The entire quantitative detection process can be completed within 30 min, boasting an exceptional limit of detection as low as 1.0 CFU mL-1. The method exhibits a broad working range for the determination of Staphylococcus aureus, with concentrations spanning 2.15 CFU mL-1 to 2.15 × 105 CFU mL-1. Furthermore, it demonstrates outstanding precision, with relative standard deviation values consistently below 5.0%. As a showcase to validate the practicality of the SERS method, we conducted tests on determining Staphylococcus aureus in a herbal food supplement, i.e., Ginkgo Biloba extract (GBE); the results align closely with those obtained through the conventional lysogeny broth agar plate method, pointing to the potential applicability in real-world scenarios.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Nanopartículas del Metal , Animales , Staphylococcus aureus , Nanopartículas del Metal/química , Erizos , Espectrometría Raman/métodos , Técnicas Biosensibles/métodos , Oro/química , Aptámeros de Nucleótidos/química , Suplementos Dietéticos
2.
Vector Borne Zoonotic Dis ; 20(8): 580-585, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32301684

RESUMEN

Coxiella burnetii is the causative agent of query fever (Q fever), and distributes broadly in environment. Livestock are identified as main reservoirs, which may infect people through their contaminative urine, feces, milk, and birth products. Wild animals can also be the potential carriers and transmitters of C. burnetii. To understand the geographic distribution and host species of C. burnetii in China, we investigated the prevalence of C. burnetii in hedgehogs (Erinaceus amurensis) in Hubei Province. Hedgehogs were tested for C. burnetii with PCR targeting three genes (com1, rrs, and icd) followed by multispacer sequence typing (MST). We found that 12.2% (5/41) hedgehogs were PCR positive for C. burnetii. MST revealed presence of two novel genotypes and phylogenetic analysis revealed that the strains were similar to a group of isolates from chronic Q fever patients and mammals. This study showed that C. burnetii are highly prevalent in hedgehogs in Hubei Province in central China, suggesting that hedgehogs may play an important role in the ecology and transmission of C. burnetii to humans because it is captured and used as traditional medicine in China.


Asunto(s)
Coxiella burnetii/aislamiento & purificación , Erizos/microbiología , Fiebre Q/veterinaria , Animales , China/epidemiología , Coxiella burnetii/clasificación , Coxiella burnetii/genética , ADN Bacteriano , Genotipo , Filogenia , Reacción en Cadena de la Polimerasa , Prevalencia , Fiebre Q/epidemiología
3.
Acta Parasitol ; 64(1): 195-204, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30666546

RESUMEN

Moniliformis cryptosaudi n. sp. (Moniliformidae) is an acanthocephalan described from the long-eared hedgehog Hemiechinus auritus (Gmelin) (Erinaceidae) in Iraq as an incipient cryptic species of Moniliformis saudi Amin, Heckmann, Mohammed, Evans, 2016 described from the desert hedgehog Paraechinus aethiopicus (Ehrenberg) (Erinaceidae) in Saudi Arabia. Microscopical studies demonstrate that the two species are morphologically indistinguishable with practically identical measurements and counts but differed significantly in their energy dispersive X-ray analysis (EDXA) of metal composition of hooks. Hooks of specimens of the new species appeared to be of collagen material with very low levels of phosphorus and calcium unlike those of M. saudi and Moniliformis kalahariensis Meyer, 1931 that had high levels of calcium and phosphorus. Using 18S rDNA and cox1 genes, M. Saudi and M. kalahariensis were shown to be molecularly distinct but the molecular profiles of M. saudi and M. cryptosaudi were more similar. The molecular profile of M. kalahariensis collected from the South African hedgehog Atelerix frontalis Smith (Erinaceidae) in South Africa is reported for the first time and is studied only for comparative purposes. Moniliformis saudi and M. kalahariensis had comparable EDXA metal analysis that was distinct from that of M. cryptosaudi.


Asunto(s)
Erizos/parasitología , Helmintiasis Animal/parasitología , Moniliformis/clasificación , Moniliformis/aislamiento & purificación , Animales , Arabia , Calcio/análisis , Análisis por Conglomerados , ADN de Helmintos/química , ADN de Helmintos/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Complejo IV de Transporte de Electrones/genética , Irak , Microscopía , Moniliformis/anatomía & histología , Moniliformis/genética , Fósforo/análisis , Filogenia , ARN Ribosómico 18S/genética , Arabia Saudita , Análisis de Secuencia de ADN , Espectrometría por Rayos X
4.
Vet Pathol ; 55(5): 711-718, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29673307

RESUMEN

Wobbly hedgehog syndrome (WHS) is a leading cause of neurologic disease in African pygmy hedgehogs (APHs; Atelerix albiventris). This study describes the signalment, clinical signs, gross, microscopic, and ultrastructural lesions of WHS in a cohort of 12 pet APHs. Microscopically, lesions consisted of status spongiosus of the white matter, typically bilateral and symmetrical, with myelin degeneration and loss that was accompanied by neuronal/axonal degeneration plus reactive microgliosis and mild, focal astrocytosis and astrogliosis. Lesions were most severe in the cerebellum and medulla oblongata, as well as cervical and thoracic spinal cord. Less affected areas were the corona radiata, corpus callosum, corpus striatum, internal capsule, and the mesencephalon. Ultrastructurally, the lesions consisted of splitting of the myelin sheath at the intraperiod line with subsequent focal expansion, resulting in status spongiosus, disruption, dilatation, rhexis, and phagocytosis. Based on these results, WHS is best described as a "spongy myelinopathy" with widespread central nervous system involvement.


Asunto(s)
Erizos , Enfermedades Neurodegenerativas/veterinaria , Animales , Cerebelo/patología , Femenino , Masculino , Bulbo Raquídeo/patología , Enfermedades Neurodegenerativas/patología , Síndrome , Tálamo/patología , Nervio Trigémino/patología , Sustancia Blanca/patología
5.
JCI Insight ; 2(21)2017 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-29093271

RESUMEN

Advanced basal cell carcinomas (BCCs) circumvent Smoothened (SMO) inhibition by activating GLI transcription factors to sustain the high levels of Hedgehog (HH) signaling required for their survival. Unfortunately, there is a lack of efficacious therapies. We performed a gene expression-based drug repositioning screen in silico and identified the FDA-approved histone deacetylase (HDAC) inhibitor, vorinostat, as a top therapeutic candidate. We show that vorinostat only inhibits proliferation of BCC cells in vitro and BCC allografts in vivo at high dose, limiting its usefulness as a monotherapy. We leveraged this in silico approach to identify drug combinations that increase the therapeutic window of vorinostat and identified atypical PKC Ɩ/ʎ (aPKC) as a HDAC costimulator of HH signaling. We found that aPKC promotes GLI1-HDAC1 association in vitro, linking two positive feedback loops. Combination targeting of HDAC1 and aPKC robustly inhibited GLI1, lowering drug doses needed in vitro, in vivo, and ex vivo in patient-derived BCC explants. We identified a bioavailable and selective small-molecule aPKC inhibitor, bringing the pharmacological blockade of aPKC and HDAC1 into the realm of clinical possibility. Our findings provide a compelling rationale and candidate drugs for combined targeting of HDAC1 and aPKC in HH-dependent cancers.


Asunto(s)
Carcinoma Basocelular/tratamiento farmacológico , Histona Desacetilasa 1/efectos de los fármacos , Inhibidores de Histona Desacetilasas/farmacología , Isoenzimas/efectos de los fármacos , Proteína Quinasa C/efectos de los fármacos , Neoplasias Cutáneas/tratamiento farmacológico , Aloinjertos , Animales , Carcinoma Basocelular/genética , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Biología Computacional , Combinación de Medicamentos , Descubrimiento de Drogas , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Erizos/genética , Erizos/metabolismo , Histona Desacetilasa 1/genética , Histona Desacetilasa 1/metabolismo , Inhibidores de Histona Desacetilasas/química , Isoenzimas/metabolismo , Ratones , Ratones Noqueados , Proteína Quinasa C/metabolismo , Transducción de Señal , Factores de Transcripción/efectos de los fármacos , Factores de Transcripción/genética , Proteína con Dedos de Zinc GLI1/genética , Proteína con Dedos de Zinc GLI1/metabolismo
6.
Nat Prod Commun ; 11(6): 747-8, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27534107

RESUMEN

Two new 13, 14/14, 15-disecopregnane-type skeleton C21 steroidal aglycones, neocynapanogenin G (1) and neocynapanogenin H (2), were isolated from the hydrolyzed extract of the CHCl3 soluble extract of the roots of Cynanchun paniculatum. Their structures were determined on the basis of chemical evidence and extensive spectroscopic methods, including 1D and 2D NMR spectroscopy. Compound 1 displayed signifidant inhibition of the Hedgehog signaling pathway in vitro.


Asunto(s)
Cynanchum/química , Medicamentos Herbarios Chinos/química , Iridoides/química , Raíces de Plantas/química , Esteroides/química , Animales , Línea Celular , Erizos/genética , Erizos/metabolismo , Humanos , Estructura Molecular , Transducción de Señal/efectos de los fármacos
7.
Int Immunopharmacol ; 34: 129-138, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26945831

RESUMEN

The present study aimed to investigate the effect of palmatine (Pal) in a rabbit osteoarthritis (OA) model in vivo and rabbit interleukin-1ß (IL-1ß)-stimulated chondrocytes in vitro. Appropriate concentrations of Pal were identified by the MTT assay and used to preincubate IL-1ß-induced chondrocytes, as well as an activator or inhibitor of Wnt and Hedgehog signaling pathways. Matrix metalloproteinase (MMP)-1, 3, and 13; tissue inhibitor of metalloproteinase (TIMP)-1; collagenase II; aggrecan; and the related molecules of the Wnt/ß-catenin and Hedgehog signaling pathways were investigated. Protein expression was detected by Western blot analysis and messenger RNA (mRNA) expression was examined by PCR analysis. Pal (0.3 mL, 100 mg/L) was injected into rabbit knee joints and histological examination, immunohistochemistry, and Mankin scoring of the articular cartilage were performed. Pal (10-100 mg/L) had no effect on chondrocyte viability, decreased the expression of the MMPs, and increased the synthesis of TIMP-1whereas collagenase II and aggrecan were inhibited by IL-1ß. When the activator (Licl) and inhibitor (DKK-1) of the Wnt/ß-catenin signaling pathway as well as the inhibitor (cyclopamine) of the Hedgehog signaling pathway were added, the Wnt/ß-catenin signaling pathway was less inhibited by Pal, and a similar inhibitory effect of cyclopamine on the Hedgehog signaling pathway was evident. Additionally, Pal enhanced the effect of cyclopamine. The histological examination, immunohistochemistry and Mankin scoring also demonstrated the protective effect of Pal, and the inhibition of the Wnt and Hedgehog signaling pathways by Pal. Pal may be useful in the treatment of OA, in which its effect is likely mediated via the Wnt/ß-catenin and Hedgehog signaling pathways.


Asunto(s)
Alcaloides de Berberina/uso terapéutico , Condrocitos/efectos de los fármacos , Erizos/metabolismo , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Osteoartritis/tratamiento farmacológico , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Animales , Células Cultivadas , Condrocitos/fisiología , Sinergismo Farmacológico , Humanos , Interleucina-1beta/inmunología , Cloruro de Litio/farmacología , Metaloproteinasas de la Matriz/metabolismo , Conejos , Inhibidor Tisular de Metaloproteinasa-1/genética , Inhibidor Tisular de Metaloproteinasa-1/metabolismo , Veratrum/inmunología , Alcaloides de Veratrum/farmacología , Vía de Señalización Wnt/efectos de los fármacos
8.
J Agric Food Chem ; 62(17): 3759-67, 2014 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-24724627

RESUMEN

In breast cancer, the cytokine tumor necrosis factor-α (TNF-α) induces cell invasion, although the molecular basis of it has not been clearly elucidated. In this study, we investigated the role of daidzein in regulating TNF-α induced cell invasion and the underlying molecular mechanisms. Daidzein inhibited TNF-α induced cellular migration and invasion in estrogen receptor (ER) negative MCF10DCIS.com human breast cancer cells. TNF-α activated Hedgehog (Hh) signaling by enhancing Gli1 nuclear translocation and transcriptional activity, which resulted in increased invasiveness; these effects were blocked by daidzein and the Hh signaling inhibitors, cyclopamine and vismodegib. Moreover, these compounds suppressed TNF-α induced matrix metalloproteinase (MMP)-9 mRNA expression and activity. Taken together, mammary tumor cell invasiveness was stimulated by TNF-α induced activation of Hh signaling; these effects were abrogated by daidzein, which suppressed Gli1 activation, thereby inhibiting migration and invasion.


Asunto(s)
Neoplasias de la Mama/fisiopatología , Glycine max/química , Erizos/metabolismo , Isoflavonas/farmacología , Proteínas Oncogénicas/metabolismo , Extractos Vegetales/farmacología , Transducción de Señal/efectos de los fármacos , Transactivadores/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Nucléolo Celular/genética , Nucléolo Celular/metabolismo , Regulación hacia Abajo/efectos de los fármacos , Femenino , Erizos/genética , Humanos , Invasividad Neoplásica/genética , Proteínas Oncogénicas/genética , Transactivadores/genética , Factor de Necrosis Tumoral alfa/genética , Proteína con Dedos de Zinc GLI1
9.
Rev Sci Tech ; 29(2): 311-27, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20919585

RESUMEN

This paper provides a 'long view' of the eradication and control of invasive mammals by reviewing the management of 24 mammalian species that have been introduced into Great Britain since the Neolithic period and have subsequently established free-living populations in the wild. The approach provides examples of the issues faced when managing populations and examines some of the lessons that can be learned from successes and failures. The species are covered in the order of introduction, with the control/eradication of rabbit (Oryctolagus cuniculus), muskrat (Ondatra zibethicus), coypu (Myocastor coypus) and American mink (Mustela vison) considered in more detail. The species accounts are set within the context of commitments for the control of invasive alien species made by parties to the Convention on Biological Diversity and guidance provided by the International Union for Conservation of Nature and the Council of Europe. These have led to improvements in the process for assessing risks and co-ordinating action. However, despite some notable cases documented here, there have been few successful eradication programmes carried out in Europe. This paper argues that there is a case for building on the improved frameworks that are being developed in the United Kingdom and elsewhere and for being more ambitious with goals for the management of invasive alien species.


Asunto(s)
Especies Introducidas , Mamíferos/fisiología , Animales , Ciervos/fisiología , Liebres/fisiología , Erizos/fisiología , Historia del Siglo XV , Historia del Siglo XVI , Historia del Siglo XVII , Historia del Siglo XVIII , Historia del Siglo XIX , Historia del Siglo XX , Historia Antigua , Historia Medieval , Humanos , Especies Introducidas/historia , Visón/fisiología , Conejos , Roedores/fisiología , Sus scrofa/fisiología , Reino Unido
10.
Arch Environ Contam Toxicol ; 59(4): 642-51, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20372884

RESUMEN

Many insectivores have been shown to be sensitive to heavy metals and therefore suitable for biomonitoring purposes. In Finland, the hibernation period of the European hedgehog (Erinaceus europaeus) is long, and during hibernation the stress caused by environmental toxins may be crucial. Concentrations of cadmium (Cd), copper (Cu), iron (Fe), magnesium (Mg), manganese (Mn), molybdenum (Mo), nickel (Ni), lead (Pb), arsenic (As), and selenium (Se) were measured in a population of hedgehogs in the town of Joensuu in eastern Finland during the summers of 2004 and 2005. The analyzed tissues were kidney, liver, hair, and spine. The sampled hedgehogs (n = 65) were mainly road-killed animals. As expected, the concentrations of heavy metals were low because the hedgehogs were living in a comparatively unpolluted area. Significant increases with age were found in Cd concentrations (kidney, liver, and spine) and some essential elements (Se in spine, kidney, and liver; Mo in kidney and liver; Cu in spine; Fe in liver; and Mn in spine). Age accumulation and correlations between Se and Cd and between Mo and Cd may indicate the protective roles of Se and Mo against Cd toxicity in hedgehogs, in which Cd is already at comparatively low concentrations. Sex had no significant effect on concentrations of the elements studied. In conclusion, age is an important parameter to be taken into account when studying heavy-metal concentrations in hedgehogs and other insectivores.


Asunto(s)
Arsénico/metabolismo , Contaminantes Ambientales/metabolismo , Erizos/metabolismo , Metales/metabolismo , Selenio/metabolismo , Factores de Edad , Animales , Exposición a Riesgos Ambientales/estadística & datos numéricos , Monitoreo del Ambiente , Femenino , Cabello/metabolismo , Riñón/metabolismo , Hígado/metabolismo , Masculino , Factores Sexuales , Columna Vertebral/metabolismo
11.
Brain Res ; 1100(1): 78-92, 2006 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-16777080

RESUMEN

Unlike the basal ganglia input from the midline and intralaminar nuclei, the origin and prominence of striatal projections arising in the lateral thalamus varies considerably among mammals being most restricted in the opossum and monkey, most extensive in the rat. To get further insight into the evolution of thalamo-striatal pathways the Madagascar lesser hedgehog tenrec (Afrotheria) was investigated using anterograde and retrograde flow techniques. An extensive medial thalamic region (including presumed equivalents to the paraventricular, parataenial and dorsomedial nuclei as well as the reuniens complex), the rostral (central) and caudal (parafascicular) intralaminar nuclei were shown to give rise to striatal projections. Additional projections originated in the ventral anterolateral nuclear group and regions within and around the medial geniculate complex. Similar to the rat there was also substantial projections from the lateral posterior-pulvinar complex and the ventral posterior nucleus. The fibers terminated extensively across the striatum in a mainly homogeneous fashion. Isolated patches of low-density terminations were found in the caudoputamen. This inhomogeneous labeling pattern appeared similar to one described in the cat with the unlabeled islands showing features of striosomes. The medial and intralaminar nuclei also projected heavily upon the olfactory tubercle. Differential innervation patterns were noted in the polymorphous layer, the deep and the superficial molecular layer.


Asunto(s)
Erizos/fisiología , Neostriado/fisiología , Vías Nerviosas/fisiología , Tálamo/fisiología , Animales , Mapeo Encefálico , Núcleos Talámicos Laterales/fisiología , Núcleos Talámicos de la Línea Media/fisiología , Sondas Moleculares , Aglutinina del Germen de Trigo-Peroxidasa de Rábano Silvestre Conjugada
12.
J Comp Pathol ; 126(1): 76-8, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11814325

RESUMEN

An adult pygmy African hedgehog developed acute posterior paresis attributed to a prolapsed intervertebral disc diagnosed by C-T scan. Corticosteroid therapy resulted in prompt resolution of the ataxia, but 2 weeks later the animal became anorexic and died. Macroscopically, the liver was stippled with punctate off-white foci which were confirmed microscopically to be foci of necrosis. Numerous hepatocytes contained intranuclear inclusions and syncytial cell formation was also present. A herpes virus was isolated and identified by fluorescent antibody and polymerase chain reaction studies as herpesvirus simplex type 1. To our knowledge, this is the first report of herpes infection in the African hedgehog and the first time herpes simplex has been identified as a cause of disease in insectivores.


Asunto(s)
Animales de Zoológico , Erizos , Herpes Simple/veterinaria , Simplexvirus/aislamiento & purificación , Animales , Antígenos Virales/análisis , ADN Viral/análisis , Resultado Fatal , Femenino , Técnica del Anticuerpo Fluorescente Directa , Herpes Simple/patología , Técnicas para Inmunoenzimas , Cuerpos de Inclusión/ultraestructura , Hígado/patología , Hígado/virología , Paresia/etiología , Paresia/patología , Paresia/veterinaria , Reacción en Cadena de la Polimerasa , Simplexvirus/genética , Simplexvirus/inmunología , Tálamo/patología , Tálamo/virología
13.
J Comp Neurol ; 402(3): 313-26, 1998 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-9853902

RESUMEN

To gain more insight into the evolution and functional significance of cerebrocerebellar circuits, the cerebellothalamic projections were studied with anterograde tracer substances in the Madagascan lesser hedgehog, tenrec. This insectivore shows one of the lowest size indices among mammals for both the cerebellar nuclei and the neocortex. Almost all cerebellodiencephalic target areas found in the tenrec have been described in other mammals. The intensity and extent of particular projections, however, vary considerably in the tenrec compared with the other mammals investigated so far. The most remarkable finding may be the tenrec's cerebellar projection to the nucleus ventralis medialis. This projection is the most prominent cerebellothalamic projection and originates in predominantly the lateral portion of the cerebellar nuclear complex. The projection to the caudolateral portion of the ventralis anterior complex (VAC) is located immediately rostral to the area receiving ascending somatosensory afferents and appears to originate, in particular, from the intermediate cerebellar nuclear complex. Another cerebellothalamic focus of terminations lies in the paralamellar region of the VAC, whereas the proper intralaminar nuclei, at best, receive a sparse cerebellar input. A faint-to-moderate projection, on the other hand, has been traced consistently to the ventral portion of the lateralis posterior-pulvinar complex and the adjacent dorsal geniculate nucleus. In addition, there are prominent cerebellosubthalamic projections to the zona incerta and the ventral geniculate nucleus. The latter projection is confined mainly to the ventralmost subdivision, which has been shown previously to receive ascending somatosensory, but not retinal, afferents. With the exception of the nucleus ventralis medialis, the projections were essentially confined to the contralateral side.


Asunto(s)
Núcleos Cerebelosos/fisiología , Erizos/fisiología , Neuronas Aferentes/fisiología , Tálamo/fisiología , Vías Aferentes/anatomía & histología , Vías Aferentes/fisiología , Animales , Núcleos Cerebelosos/anatomía & histología , Sondas Moleculares , Núcleos Talámicos/anatomía & histología , Núcleos Talámicos/fisiología , Tálamo/anatomía & histología , Aglutinina del Germen de Trigo-Peroxidasa de Rábano Silvestre Conjugada
14.
Neuroscience ; 86(2): 651-61, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9881877

RESUMEN

The objective of the present study was the identification and characterization of the trigemino-diencephalic target areas in the Madagascan lesser hedgehog tenrec in order to get a more comprehensive view on the mammalian somatosensory thalamus, its evolution and representation in different species. Such an analysis has been considered important because in lower mammals the head and face are relatively well represented, but their ascending trigeminal projections have scarcely been analysed. Following injections of different tracer substances into the rostral and caudal portions of the trigeminal nuclear complex the most prominent area of termination was found in the medial ventroposterior nucleus. These projections were patchy and scarcely overlapped the region previously shown to receive spinal and dorsal column nuclear afferents. On the basis of the laterality and the intensity of the projections, two subdivisions were distinguished, the principal portion and the accessory portion receiving a dense contralateral and a weak bilateral input, respectively. They were considered equivalents to the magnocellular and parvocellular subdivisions of the medial ventroposterior nucleus in more differentiated mammals. In the latter species, however, the overlap between trigeminal and parabrachial fibres appears less extensive than in the tenrec. In addition, a weak bilateral projection was shown from the caudal trigeminal nucleus to the caudal and dorsal subdivision of the nucleus submedius. There was little, if any evidence for a trigeminal projection to the intralaminar nuclei and we failed to identify a correlate to the posterior nuclear complex of higher mammals. On the other hand, there was a distinct contralateral projection to the ventral portion of the zona incerta. This projection was of similar strength as the projection to the medial ventroposterior nucleus; it supports the notion that the zona incerta may play a crucial role in relaying trigeminal information.


Asunto(s)
Diencéfalo/anatomía & histología , Erizos/anatomía & histología , Tálamo/anatomía & histología , Nervio Trigémino/anatomía & histología , Núcleos del Trigémino/anatomía & histología , Animales , Transporte Axonal , Biotina/análogos & derivados , Dextranos , Colorantes Fluorescentes , Madagascar , Aglutinina del Germen de Trigo-Peroxidasa de Rábano Silvestre Conjugada
15.
Exp Brain Res ; 111(3): 356-70, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8911930

RESUMEN

Using different tracer substances the pathways connecting the superior colliculus with the diencephalon were studied in the Madagascan hedgehog tenrec (Echinops telfairi), a nocturnal insectivore with tiny eyes, a small and little differentiated superior colliculus and a visual cortex with no obvious fourth granular layer. The most prominent tecto-thalamic projection terminated in the ipsilateral dorsal lateral geniculate nucleus. The entire region receiving contralateral retinal afferents was labeled with variable density. In addition, there was a widespread, homogeneously distributed collicular input to the lateralis posterior-pulvinar complex and a distinct tectal projection to the suprageniculate nucleus. The latter projections were bilateral with a clear ipsilateral predominance. Among the intra- and paralaminar nuclei the centralis lateralis complex was most heavily labeled on both sides, followed by the nucleus centralis medialis. The paralamellar portion of the nucleus medialis dorsalis and the nucleus parafascicularis received sparse projections. A clear projection to the nucleus ventralis medialis could not be demonstrated but its presence was not entirely excluded either. There were also projections to medial thalamic nuclei, particularly the reuniens complex and the nucleus paraventricularis thalami. The main tecto-subthalamic target regions were the zona incerta, the dorsal hypothalamus and distinct subdivisons of the ventral lateral geniculate nucleus. These regions also gave rise to projections to the superior colliculus, as did the intergeniculate leaflet. The pathways oriented toward the visual or frontal cortex and the projections possibly involved in limbic and circadian mechanisms were compared with the connectivity patterns reported in mammals with more differentiated brains. Particular attention was given to the tenrec's prominent tecto-geniculate projection, the presumed W- or K-pathway directed toward the supragranular layers.


Asunto(s)
Mapeo Encefálico , Diencéfalo/anatomía & histología , Erizos/anatomía & histología , Colículos Superiores/anatomía & histología , Corteza Visual/anatomía & histología , Animales , Cuerpos Geniculados/anatomía & histología , Hipotálamo/anatomía & histología , Microinyecciones , Núcleos Talámicos/anatomía & histología , Vías Visuales/anatomía & histología
17.
Neurosci Lett ; 189(2): 89-92, 1995 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-7541906

RESUMEN

The adult erinaceous hedgehog, unlike other mammals, has recently been shown to have prominent crossed projections from the thalamus to the motor cortex. There are suggestions relating this unique pattern of connectivity to the overall degree of brain differentiation and/or the poorly developed corpus callosum. The present tracing study demonstrates that the Madagascan lesser hedgehog tenrec, with its tiny corpus callosum and one of the lowest neocorticalization indices among insectivores, has extensive crossed cortico-thalamic projections, but essentially the same sparse thalamic projections to the contralateral cortex as have placental mammals with more differentiated brains. The implications of the findings and the relevance of extracallosal pathways are discussed.


Asunto(s)
Corteza Cerebral/anatomía & histología , Erizos/anatomía & histología , Tálamo/anatomía & histología , Animales , Cuerpo Calloso/anatomía & histología , Histocitoquímica , Peroxidasa de Rábano Silvestre , Vías Nerviosas/anatomía & histología , Especificidad de la Especie , Aglutinina del Germen de Trigo-Peroxidasa de Rábano Silvestre Conjugada , Aglutininas del Germen de Trigo
18.
Cell Tissue Res ; 278(1): 97-106, 1994 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7954706

RESUMEN

High affinity melatonin-binding sites have been described, by means of autoradiography with 2-125I-melatonin as the ligand, in more than 60 brain areas of about 20 mammalian species, with dramatic variations in the nature and number of labelled structures among the different species studied. As melatonin is involved in the synchronization of biological rhythms, we have tried to correlate the brain areas containing melatonin-binding sites with some rhythmic functions typical of given species. Therefore, we have studied the location of melatonin-binding sites in the complete brain of five long-day breeders with hibernation cycles, viz. one insectivore and four rodents. With the exception of the suprachiasmatic nuclei and the pars tuberalis of the pituitary, both of which contain binding sites in all five species, few reactive structures are common, even among species from the same family, e.g. the edible dormouse and the garden dormouse.


Asunto(s)
Química Encefálica , Mapeo Encefálico , Erizos/fisiología , Hibernación/fisiología , Proteínas del Tejido Nervioso/análisis , Periodicidad , Receptores de Superficie Celular/análisis , Roedores/fisiología , Animales , Cricetinae/anatomía & histología , Cricetinae/fisiología , Femenino , Erizos/anatomía & histología , Hipotálamo/química , Hipotálamo/fisiología , Masculino , Melatonina/análogos & derivados , Fotoperiodo , Adenohipófisis/química , Adenohipófisis/fisiología , Receptores de Melatonina , Roedores/anatomía & histología , Estaciones del Año , Especificidad de la Especie , Núcleo Supraquiasmático/química , Núcleo Supraquiasmático/fisiología
20.
Arterioscler Thromb ; 12(2): 146-54, 1992 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1531929

RESUMEN

Lipoprotein(a) (Lp[a]), a highly atherogenic lipoprotein particle, is the prominent apolipoprotein B-containing lipoprotein in the hedgehog (Laplaud PM et al, J Lipid Res 1988;29:1157-1170). In the present work, we studied the consequences of the structural homology between the specific Lp(a) glycoprotein, apoprotein(a), and plasminogen on the generation of plasmin by fibrin-bound tissue-type plasminogen activator. The activation of plasminogen was initiated by adding either native plasma or Lp(a)-free plasma supplemented with the equivalent of 0.25 mg/ml of either purified Lp(a) or albumin to a surface of fibrin prepared on micortitration plates and to which human tissue-type plasminogen activator was specifically bound. With the Lp(a)-free plasma, an increase in the binding and activation of plasminogen as a function of time was observed. In contrast, in the presence of Lp(a) (i.e., native plasma or the reconstituted system), a significant decrease in the binding of plasmin(ogen) (approximately 60%) was obtained. These data indicate that hedgehog Lp(a) interferes with the binding and activation of plasminogen at the fibrin surface and may thereby behave as a factor regulating the extent of fibrin deposition. These results support our previous data indicating that high levels of Lp(a) may have antifibrinolytic effects in humans (Rouy D et al, Arterioscler Thromb 1991;11:629-638), are in agreement with the observation that Lp(a) is a risk factor for atherosclerotic disease, and provide further support to the view of Lp(a) as a link between atherosclerosis and thrombosis.


Asunto(s)
Fibrina/fisiología , Erizos/sangre , Lipoproteínas/fisiología , Plasminógeno/fisiología , Adsorción , Animales , Proteínas Sanguíneas , Fibrina/metabolismo , Lipoproteína(a) , Lisina , Masculino , Activador de Tejido Plasminógeno/metabolismo , Activador de Tejido Plasminógeno/farmacología
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