Search results for "Tunic"

Prophenoloxidase activating system in tunicate hemolymph

1996

The activation sequence and related factors of the prophenoloxidase activating system in crustaceans was compared with the equivalent system in tunicates. Both solitary and colonial ascidians present in their hemolymph a copper-dependent phenoloxidase activity that may be inhibited by tropolone and phenylthiourea. Carbohydrates are able, to various extents, to trigger proPO system which requires serine protease cleavage for activation to phenoloxidase (PO). In some ascidians, hemocytes called ≪morula cells≫ show PO activity, while in Ciona intestinalis the ≪univacuolar refractile granulocytes≫ are positive after cytochemical staining with L-dopa. The relationships between proPO system and d…

Tunicate immunocytes can be cytotoxic toward foreign cells

2008

Effetti antiproliferativi degli estratti di emociti dell'ascidia Styela plicata ( Tunicata)

2009

USO DELLA TUNICA VAGINALE DEL TESTICOLO NELLA CHIRURGIA DELL'IPOSPADIA

1993

Urethrocutaneus fistulas are the most common complication of surgery for hypospadias. In five patients, fistulas of this type were repaired with patches of tunica vaginalis to prevent fistula recurrence. Our experience and that of others suggest that tunica vaginalis autografts can be used for treatment of a variety of urethral problems in children.

USE OF TUNICA VAGINALIS IN THE SURGERY OF HYPOSPADIAS

1992

The authors report their experience in the use of the Tunica vaginalis in the surgical correction of hypospadias and illustrate the peculiarities showing their case studies and the results obtained

Cellular components and tunic architecture of the solitary ascidian Styela canopus (Stolidobranchiata, Styelidae).

1998

Abstract Cell distribution and tunic morphology in the ascidian Styela canopus were examined by electron microscopy. The observations showed that the outer covering is composed of a thin sinuous cuticle with several protrusions and a deep layer of ground substance. The fibrous component and its arrangement in the tunic were demonstrated: elementary fibrils exhibit a ‘microtubular’ structure and an elliptical cross-sectional shape. Four types of cells were described: clear vesicular tunic granulocytes, tunic microgranulocytes, unilocular tunic granulocytes, and globular tunic granulocytes. Morphofunctional aspects of the tunic tissue and certain phylogenetic relationships are discussed.

Circulating hemocytes and pharyngeal explants of Styela clava release hemagglutinin in vitro

1997

Tunicate blood cells are a mixed population, thus experiments that assay their immunodefense responses, such as release of hemagglutinins, were done to isolate different functional hemocytic types. Two sources of hemocytes from Styela clava were used, the hemolymph and the pharynx (the hemopoietic organ). Hemolymph centrifuged through a discontinuous Percoll gradient yielded four distinct bands of hemocytes. After incubation at 15°C, circulating hemocytes and those from pharyngeal cultures released hemagglutinin after 2 and 30 days. Highest titers were found in B1 (hyaline and compartment cells), B3 (hyaline cells and eosinophil granulocytes), and B4 (hyaline cells and debris). Hemagglutina…

Microscopic features of the tunic in young Styela canopus (Tunicata, Styelidae)

The tunic is a unique tissue in metazoans covering the epidermis of ascidians and other tunicates. The tunic is a multifunctional tissue that provides support, mechanical rigidity, and protection against infection and predation. The outermost surface of it is covered by a thin continuous layer called tunic cuticle. The tunic cuticle density and integrity must be maintained during the growth of the animal after metamorphosis, as it represents the primary body surface barrier preventing the mechanical damage. Using transmission electronic microscopy we attempted to characterize the cuticle morphology of young Styela canopus, a solitary ascidian (Styelidae), in comparison with the cuticle arch…

Protective effect of paraoxonase-2 against endoplasmic reticulum stress-induced apoptosis is lost upon disturbance of calcium homoeostasis

2008

PON2 (paraoxonase-2) is a ubiquitously expressed antioxidative protein which is largely found in the ER (endoplasmic reticulum). Addressing the cytoprotective functions of PON2, we observed that PON2 overexpression provided significant resistance to ER-stress-induced caspase 3 activation when the ER stress was induced by interference with protein modification (by tunicamycin or dithiothreitol), but not when ER stress was induced by disturbance of Ca2+ homoeostasis (by thapsigargin or A23187). When analysing the underlying molecular events, we found an activation of the PON2 promoter in response to all tested ER-stress-inducing stimuli. However, only tunicamycin and dithiothreitol resulted i…

Radiologic and Intraoperative Finding of Intimal Tear in Type A Intramural Hematoma of the Aorta

2019

AbstractAortic intramural hematoma (IMH) is described as “dissection without intimal tear” due to rhexis of vasa vasorum, which results in bleeding within the tunica media in the absence of intimal disruption or blood flow communication. The aim of our study is to validate perioperative evidence of intimal entry tear in IMH patients and to suggest that this entity may represent a part of a disease and not a separate disease.