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J Stingl

Publications and source records attributed to J Stingl.

At least 19 recordsLinked to original sources
PubMed2006

[Teaching arthroscopy techniques at the Educational Center for Clinical Anatomy and Endoscopy (ECAE), Department of Anatomy, 3rd Faculty of Medicine, Charles University in Prague].

In the period from 2000 to 2005, with support of several grants, a unique multi-media center for teaching endoscopic techniques was established at the Department of Anatomy, 3rd Faculty of Medicine, Charles University in Prague. This conditions have been provided for the repeated use of cadavers preserved by a special embalming method of Professor Thiel of the Institute for Anatomy, University of Graz, for simulation of surgical procedures. One room of the Department has been converted into a small operating theatre and an audio-visual network with wireless Internet connection covers the whole dissection unit of the Department. A graphic studio for production of teaching materials has also been set up. The course in dissection for the first- and second-year medical students also includes demo arthroscopy. In addition to the courses for students, postgraduate courses for young surgeons are organized. These provide an opportunity to learn about techniques and instruments employed in a broad range of arthroscopic procedures, using appropriate cadaver materials.

Arthroscopy↗
PubMed2004

Early postnatal growth of the initial lymphatics in the ventral stripe of spinotrapezius muscle of the rat.

The aim of this study was the morphological description of the early postnatal growth of initial lymphatics in the ventral stripe of the spinotrapezius muscle of the rat. Electron-microscopically it was found that in the muscles of newborn rats no well-developed lymphatics were apparent, but the presence of specifically polarized mesenchymal cells in the close vicinity of central blood vessels was evident. In animals aged one-day through two-weeks-old, those modified mesenchymal cells continuously joined with one another, to form simple intercellular contacts and incomplete lymphatic lumina. Morphologically, they were well demarcated relative to the surrounding muscular interstitium. In three-week-old rats, all intramuscular lymphatics were well developed, including fine intraluminal valves, and their endothelial cells presented slight pinocytotic activity and a complete absence of a basal lamina. In growing lymphatic endothelial cells, no mitoses or signs of sprouting, typical for the growth of blood capillaries, were found. In conclusion, a possible morphological mechanism enabling the expansion of the growing lymphatic endothelial cells could be the specific remodeling of cytoplasmic vacuoles accumulated in the peripheral cellular processes.

Animals↗
PubMed2003

Vasa vasorum of the human great saphenous vein.

The distribution of the vasa vasorum of the human great saphenous vein (GSV) was studied on veins taken both post-mortem and peroperatively. It was found that the stems of feeding vessels approach the venous wall at intervals of 1.5-2.5 cm; their smaller branches first passed the fascial compartments of the GSV and then entered the adventitia at intervals of 0.5-1.5 cm on both the stem and the largest tributaries of the GSV. In the stem regions vasa vasorum arteries and veins ran together but, between neighboring stems, isolated venae vasorum were regularly found which opened individually into terminal segments of the largest tributaries of the GSV. Neither by dissection nor by injection methods were venae vasorum found to open directly into the lumen of the GSV stem. The total thickness of the media ranged between 500 and 1300 micro m, according to the state of constriction of the venous wall before fixation. Two structurally different layers of GSV tunica media were present: an inner loose layer and an outer dense layer, both of similar thickness. The innermost capillaries of the vasa vasorum network were found in all cases on the border between the two layers of media. No lymphatic was found in any of the layers of GSV wall. From the findings the authors recommend extremely careful dissection of the GSV wall during in situ grafting surgery, to ensure the best viability of the venous wall.

Aged↗
PubMed2002

Morphology and some biomechanical properties of human liver and spleen.

The aim of the study was an experimental determination of some morphological and mechanical properties of human liver and spleen (amount of collagen in organ capsules, their critical tension and density), followed by a definition of the threshold of critical acceleration, above which the organs can be injured during a car crash. Experiments were done on 33 fresh cadavers (18 males, 15 females; age 3 months to 88 years), and completed by sled tests on dummies testing the loads of both hypochondrial regions protected by air bags and/or seat belts. Results obtained were the following: (1). liver: capsule collagen 14-35%, critical tension 0.066-0.386 MPa, density 0.92-1.19 g/ml, critical acceleration 48-155 g; (2). spleen: capsule collagen 1.8-24.4%, critical tension 0.022-0.652 MPa, density 0.85-1.25 g/ml, critical acceleration 33-149 g. Loads of both hypochondrial regions measured on dummies during a predefined sled test were 34-67 g. Results obtained were evaluated qualitatively and discussed from the point of view of their possible use in future passive safety engineering and design calculations.

Acceleration↗
PubMed2001

Characterization of bipotent mammary epithelial progenitor cells in normal adult human breast tissue.

The purpose of the present study was to characterize primitive epithelial progenitor populations present in adult normal human mammary tissue using a combination of flow cytometry and in vitro colony assay procedures. Three types of human breast epithelial cell (HBEC) progenitors were identified: luminal-restricted, myoepithelial-restricted and bipotent progenitors. The first type expressed epithelial cell adhesion molecule (EpCAM), alpha6 integrin and MUC1 and generated colonies composed exclusively of cells positive for the luminal-associated markers keratin 8/18, keratin 19, EpCAM and MUC1. Bipotent progenitors produced colonies containing a central core of cells expressing luminal markers surrounded by keratin 14+ myoepithelial-like cells. Single cell cultures confirmed the bipotentiality of these progenitors. Their high expression of alpha6 integrin and low expression of MUC1 suggests a basal position of these cells in the mammary epithelium in vivo. Serial passage in vitro of an enriched population of bipotent progenitors demonstrated that only myoepithelial-restricted progenitors could be readily generated under the culture conditions used. These results support a hierarchical branching model of HBEC progenitor differentiation from a primitive uncommitted cell to luminal- and myoepithelial-restricted progenitors.

Antigens, Neoplasm↗
PubMed1999

[Correct use of anatomic nomenclature in selected Czech professional journals].

The objective was to assess in a qualitative study how correctly anatomical terms are used in four selected Czech medical journals (Acta Chirurgiae Orthopaedicae and Traumatologicae Cechoslovaca, Ceská gynecology, Ceská radiology and Rozhledy v chirurgii, 1990-1996). A total of 1200 articles were evaluated where 145 anatomical terms were detected which differed from P.N.A. and from Nomina Anatomica valid at present. Of these 25 were terms from B.N.A. (4) and from I.N.A. (21). Approximately twice as frequent were anatomical and clinical eponyms (52). The highest ratio (71) was formed by incorrect terms (36 Latin and 35 Czech). The authors feel that in the improvement of the standard of exact anatomical terminology in clinical medicine as well as in the professional literature in future a part should be played by better teaching at medical faculties within the framework of the new curriculum and by higher demands on the standard of manuscripts accepted by editors of professional journals.

Anatomy↗
PubMed1998

Phenotypic and functional characterization in vitro of a multipotent epithelial cell present in the normal adult human breast.

The developmental relationships between the different mammary epithelial cell lineages in the human mammary gland are not well defined. To characterize human breast epithelial cells (HBEC) with progenitor activity, we used flow cytometry and single cell sorting to analyze the distribution of cellular phenotypes in primary cultures of reduction mammoplasties and their associated ability to generate colonies in 2-dimensional (D) and 3-D (collagen gel) culture systems. This approach allowed two distinct types of HBEC progenitor populations to be distinguished on the basis of their differential expression of the MUC-1 glycoprotein, CALLA/CD10 and epithelial-specific antigen (ESA). The first type of progenitor, which is enriched in the MUC-1+/CAL-LA-/ESA+ subpopulation, generated colonies of tightly arranged cells in 2-D cultures and small alveolar-like colonies with a central lumen when cultured in a collagen matrix. The cells produced in the colonies and derived from these MUC-1+/CALLA-/ESA+ progenitors were found to express typical luminal epitopes (keratin 8/18, keratin 19, MUC-1, ESA) and showed low levels of expression of myoepithelial epitopes (keratin 14 and CD44v6). The second type of progenitor, which is present in the MUC-1-to +/-/CALLA +/- to +/ESA+ subpopulation, generated mixed colonies of both luminal and myoepithelial cells when seeded in 2-D and 3-D cultures. In 2-D cultures, the centrally located cells exhibited a luminal morphology and expressed ESA, but were heterogeneous in their expression of MUC-1. Radiating from the periphery of these ESA+ HBEC were highly refractile ESA- teardrop-shaped myoepithelial-like cells. When cultured in a collagen matrix, these bipotent progenitors generated large branched colonies composed of a heterogeneous population of cells, with some of the progeny cells expressing luminal epitopes (keratin 8/18, keratin 19 and MUC-1) and others expressing myoepithelial epitopes (keratin 14 and CD44v6). A third type of progenitor, which became apparent is passaged HBEC cultures and was enriched in the MUC-1-/CALLA+/ESA- subpopulation, was found to generate colonies of cells with an exclusively myoepithelial phenotype. These results provide definitive evidence for the existence of multilineage HBEC progenitors in normal adult human mammary tissue. The phenotypic profile of these cells suggest that these multilineage progenitors are a relatively undifferentiated cell since they express low levels of MUC-1 and that they have a luminal location within the mammary epithelium since they are ESA+. Furthermore, we suggest that the MUC-1+/CALLA-/ESA+ and the MUC-1- to +/-/CALLA +/- to +/ESA+ progenitors we have identified and characterized are candidate in vivo alveolar and ductal progenitors, respectively.

Actins↗
PubMed1996

Selective growth of freshly isolated human breast epithelial cells cultured at low concentrations in the presence or absence of bone marrow cells.

In this study, we show that conditions previously found to promote the selective growth of human breast epithelial cells (HBEC) in serum-free primary cultures established from normal or malignant tissue can be extended to cultures initiated at low seeding densities (< 5000 cells/cm2). The epithelial nature of the cells produced was documented by their positive staining with antibodies specific for keratins 8, 14, and 18, and 2 antibodies that recognize epithelial-specific antigens (Ber-EP4 and HB8630). HBEC growth was not affected, either positively or negatively, by the use of a medium containing a combination of fetal calf and horse serum, which promotes the growth of many types of stromal cells and associated hematopoietic precursors, or by the inclusion in the initial cell suspension of marrow cells at HBEC to marrow cell ratios typical of bone marrow samples from patients with metastatic breast cancer. The presence of fibroblast feeders from a variety of sources enhanced the growth of HBEC to different degrees. In cultures initiated with low numbers of cells obtained from samples of breast carcinoma, HBEC growth was generally reduced by comparison to cultures of normal HBEC. With the detection methods used, it was not possible to determine the extent to which this decreased growth was due to a reduced frequency of malignant HBEC with in vitro precursor activity, or the presence of reduced numbers of residual normal HBEC precursors, or both. However, preliminary data indicate that this approach also allows the detection of some breast carcinoma cells with proliferative ability that are present in the marrow or pleural effusions of some breast cancer patients. These studies demonstrate the feasibility of detecting normal and malignant HBEC with growth potential when these are cultured at low density and/or as rare contaminants of marrow cell suspensions, and provide a starting point for their further characterization.

Bone Marrow Cells↗
PubMed1995

[Variations in extrahepatic bile ducts, their arteries and pancreatic ducts].

The author presents a brief account of congenital varieties of extrahepatic biliary pathways, a cystica and pancreatic ducts and explains their development. Good knowledge of these varieties is of great importance for detailed preparation in laparoscopic cholecystectomy and during fibroscopic examination of duodenal papillae.

Arteries↗
PubMed1994

Early postnatal growth of skeletal muscle blood vessels of the rat.

The development of blood vessels during the first three postnatal weeks was studied in the ventral stripe of the spinotrapezius muscle of the rat by use of India ink-gelatine injections, and electron microscopy. The number of terminal arterioles and collecting venules remained unchanged postnatally in the observed area. A remarkable proximodistal gradient of vascular development was apparent: while the basic structure of the hilar vessels remained unchanged in the time studied, the intramuscular arteries and veins matured gradually. More peripherally, gradual maturation of terminal and precapillary arterioles was observed. The capillary endothelium and the pericytes showed immature features, and remained unchanged during the time studied. An intense rebuilding activity was found in the endothelial cells of the growing venules, expressed by various forms of gaps, covered by an intact basal lamina and pericytes. Numerous mast cells and macrophages were found along all vessels. Intramuscular lymphatics were not present prior to the first postnatal week.

Animals↗
PubMed1994

Ontogenesis of the vascular bed in the human skeletal muscles.

The ontogenetic development of the vascular bed was studied in the muscles of human fetuses after India ink and gelatine injections. By the 12th week of intrauterine life the architectural arrangement of the largest (primary) intra-muscular vessels is qualitatively comparable with that of the adult muscles. The smaller (secondary) vessels, as well as the microcirculatory bed, have very immature features in all fetal muscles studied. This part of the vascular bed develops gradually during further time from a primitive intramuscular capillary network. The basic architectural arrangement of the microcirculatory bed in adult muscles, and the development of the structure of the hilar vessels of the gastrocnemius muscle were described in the muscles of fetuses, newborns, and adults.

Blood Vessels↗
PubMed1992

In vitro screening of crude extracts and pure metabolites obtained from marine invertebrates for the treatment of breast cancer.

A total of 15 samples (crude extracts and pure secondary metabolites) obtained from marine invertebrates collected from the offshore waters of British Columbia, Papua New Guinea, and Sri Lanka have previously been shown to exert cytotoxic activity in the in vitro L1210 leukemic bioassay. We screened these metabolites for in vitro cytotoxic activity against the drug-sensitive breast-tumor cell lines MCF-7, T-47D, ZR-75-1, and MDA-MB-231; the multidrug-resistant and P-glycoprotein (Pgp)-positive breast-tumor cell lines MCF-7 Adr and MDA-A1r; and normal and malignant human breast epithelial cells (HBEC) in primary culture. Eight samples exhibited significant [drug concentration resulting in a 50% decrease in cell growth as compared with controls (ED50), less than 25 micrograms/ml] dose-dependent cytotoxicity against the drug-sensitive cell lines; the ED50 values were as low as 0.004 micrograms/ml. Five of the eight samples exhibited significant cytotoxicity against the multidrug-resistant cell lines; the ED50 values were as low as 0.0006 micrograms/ml. Incubation of MCF-7 Adr cells with varying concentrations of compounds in the presence of Adriamycin demonstrated that none of the compounds tested interfered with Pgp function. Results obtained using HBEC in primary culture showed a wide range of chemosensitivities for a given drug against tissue taken from different patients, demonstrating the uniqueness of the response of different individuals to chemotherapy.

Animals↗
PubMed1990

[The history of morphological research of the vascular bed of the skeletal muscles].

The present paper briefly reports on the history of vascular research with special emphasis to the contribution of G. Prochaska and W. Spalteholz in the topic of the vascular pattern in the skeletal muscle. The merit of Prochaska was to summarize the findings of earlier investigators and to perform own experiments using injection techniques to demonstrate vessels in the muscle. For a longer period his results has served as the morphological base for the physiological understanding of the muscular circulation. 100 years later W. Spalteholz was the first scientist which has elaborated a complete scheme of the vascular distribution in the muscle including the capillaries, using his special method, to make tissue translucent combined with injection techniques. His fundamental work "Die Vertheilung der Blutgefässe im Muskel" was published in 1888. In many details it is valid up to recent time because the concept of Chambers and Zweifach can not be applied to the circulation of the muscle. Additionally our report gives information of further development of vascular research in the muscle with respects to theoretical problems and practical application in the muscle surgery.

Anatomy↗
PubMed1989

[Normal anatomy of the Achilles tendon].

The paper contains introductory historic and nomenclature comments, survey of topography and basic morphological modifications of Achilles tendon including description of all m. triceps surae components. Morphology of the distal third and tendon insertion, bursa calcanea and arterial supply of both the tendon and its sheaths is described in detail. The paper is concluded by a brief survey of tendon ontogenesis. With respect to its general topic the paper provides morphological basis for topical clinical needs especially in sports medicine and orthopedics.

Achilles Tendon↗