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E Pokorná

Publications and source records attributed to E Pokorná.

At least 19 recordsLinked to original sources
PubMed2005

Immune characterization of the Lewis rats inoculated with K2 sarcoma cell line and newly derived R5-28 malignant cells.

Sarcoma is a relatively rare malignant disease with high mortality, bad prognosis and response to conventional therapy. Two possible models of this disease were tested: the K2 rat sarcoma cell line, which was described previously, and the new rat R5-28 cell line derived from a spontaneously growing rat neoplasm with sarcoma morphology. While all rats inoculated with K2 cells developed tumours at 22th-25th day after inoculation (D = 22-25), only 60%-75% of R5-28-inoculated rats were affected by tumours. The frequency and progress of the disease depended on the number of inoculated cells. No metastases were detected in both cases. All affected animals showed large splenomegaly. A possible response of some immune system components to tumours was tested. No tumour-infiltrating lymphocytes were revealed in the tumour tissue. Anti-tumour antibodies were not found in tumour-bearing animal sera. Appropriate changes in peripheral blood lymphocyte subsets were explored. While the relative numbers of both NK cells and Tc were impaired, no changes were noted in numbers of CD4+CD8- T helper cells. Leukocytosis with highly increased numbers of CD11b+ myeloid cells displaying variable expression of CD4 was detected in terminal stages of the disease.

Animals↗
PubMed2005

[The risk of malignancy after organ transplantation].

Improvements in immunosuppressive therapy during the past decade brought about improvements of the long term tolerance of organ allografts. However, the long-term immunosuppressive therapy has an important limitation, because it can increase the risk of cardivascular diseases, infections and tumors. As compared with age-matched healthy population, organ-transplant recipients have an increased incidence of tumors.

Humans↗
PubMed2003

Two dynamic morphotypes of sarcoma cells, asymmetric stellate and triangle with leading lamella, are related to malignancy.

A notion of the dynamic morphotype was developed as a conjunction between cell shape and migration. This enabled the investigation of the relationship between malignancy and patterns of dynamic morphology in neoplastic cells in vitro. Time-lapse cinemicroscopy was used to analyse the cell behaviour of three rat neoplastic cell lines (K2, T15, and A8), differing in metastatic potential, that were instrumental in revealing a coincidence between high migratory activity and appearance of the 3D structure of actin cables in high-malignant A8 cells (Pokorná et al., 1994). A set of criteria was established for visual classification of cell morphology. Matching the pattern of cell morphology with locomotory activity led to identification of four dynamic morphotypes. Cell speed was determined by tracking and the dynamic morphotypes assigned by the operator. All the three cell populations were studied for incidence of the dynamic morphotypes in culture media differing in pH: 6.6 simulating acid extracellular condition in tumours, physiological 7.4, and alkaline 8.2. The results showed that acid pH stimulated motile activity in the intermediate-malignant T15 and most malignant A8 cells. The T15 and A8 cells also manifested a prolonged continuation of fast locomotion in the early G1 phase and displayed a prevalence of two fast moving dynamic morphotypes: asymmetric stellate and triangle with leading lamella.

Animals↗
PubMed2003

[The results of kidney transplantation from very young paediatric cadaveric donors to adult recipients in Czech Republic in the years 1994-2001 (retrospective study of the Czech transplant centres)].

The results of kidney transplantation from very young paediatric cadaveric donors up to five years, which were transplanted to adult recipients, are evaluated in the first retrospective study of all Czech transplantcentres. In general, 42 of these transplantations were carried out during 1994-2001. In 28 cases single kidney was transplanted, in 14 cases en bloc graft of both children kidneys was transplanted. The reasons of kidney failure by recipients are usual (in 42.9% glomerulonephritis). An average age of the donors was 34.7 months (median 39 months). An average age of the recipients during transplantation was 42.6 years (median 43.5 years). All the kidneys were placed into retroperitoneum. As long as only single kidney was transplanted, the rules, already propagated by Salvatiera in 1970, were respected. At the transplantation of en bloc graft, Kinne's method with possible vessels elongation of the graft and with uretero-uretero anastomoses (in so called Ostrava modification) was used. The higher occurrence of the primary graft non-function (as 50% losses of all grafts) was confirmed in the study. Its reason was an acute thrombosis of vessels or rotation of graft stem. One-, three- and five-years patients and grafts survival were 97.6-90.5-90.5% and 76.2-73.8-73.8% actually. Patients survival are very good while grafts survival are average, momentarily a bit worse than national data published by the Czech Transplant Society, which determines one-, three- and five-years grafts survival with 90.3-82.9-75.5% and 79.1-71.1-65% actually. The kidney transplantation from paediatric cadaveric donors to adult recipients is acceptable under present allocated criteria, in case that some principles are kept. The study confirms the international experiences about rather higher incidence of surgical complications and primary graft non-function. In conclusion, some general references for reduction of complications, as well as for improvement of these transplantation results are introduced.

Adult↗
PubMed2002

Large expansion of morphologically heterogeneous mammary epithelial cells, including the luminal phenotype, from human breast tumours.

Regular expansion of heterogeneous populations of epithelial cells, including the luminal phenotype, was achieved from small biopsies of human breast tumours and cutaneous metastases by optimized feeder layer technique based on irradiated NIH 3T3 cells. Forty-one out of 47 primary tumour specimens and all three cutaneous metastases grew successfully for two to 10 passages in vitro. The main phenotypes of cultured cells and their changes in subcultures were characterized using immunocytochemistry and phase contrast microscopy (in few cases also time-lapse recording). In the majority of cultured cell populations a fraction of cells positive for keratin 19 (K19+), typical for the luminal phenotype, was detected. This is the cell type from which breast carcinoma is supposed to arise. While in cultures derived from benign lesions only basic phenotypes of luminal and myoepithelial cells were found, in cultures derived from malignant tumours unusual phenotypes of epithelial cells, in their majority K19+, were detected. The growth properties of cells from six benign and seven malignant samples were analyzed in detail. In the analyzed cell populations the culture lifetime - related to the number of colony-forming cells varied for cells from malignant tumours between 21 and 51 and from benign tumours between 22 and 40 cell generations. The total number of passages achieved was three to seven for malignant or four to nine for benign cultures. In spite of negative results of tumourigenicity testing in immunologically compromised Nu/nu mice the potential to culture apparently neoplastic cells was indicated by positive immunostaining for the p53 oncoprotein (seven of 23 tested malignant cases), the src oncoprotein (five of eight), and overexpression of the c-erbB-2 protein (five of 26). This was further confirmed by successful cultivation of malignant cells from cutaneous metastases. Two of the three metastasis-derived cultures were nearly homogeneously positive for K19 while the third was almost negative. The results proved the optimized feeder layer technique to be useful for regular yielding of large amounts of epithelial cells from small tumour biopsies and for supporting the majority of cell phenotypes present in the original tumour. Therefore, it appeared to be a promising tool for further analysis of interactions between luminal and myoepithelial cells in the development of human breast carcinoma and for the study of individual tumours.

3T3 Cells↗
PubMed2001

Y chromosome and vimentin used to trace the fate of allogeneic keratinocytes delivered to the wound by the recombined human/pig skin.

RHPS, composed of confluent allogeneic keratinocytes cultured on cell-free pig dermis, stimulates wound healing when applied with the keratinocyte layer facing the wound. So far it has not been clarified whether the confluent keratinocytes implanted 'upside-down' can 'take' or only stimulate healing by producing growth factors. Confluent male keratinocytes were grafted onto donor sites of three female patients. Biopsies were taken on days 4, 6 and 9 after grafting. The fate of donor cells was followed in paraffin sections by FISH for the Y chromosome and by persisting expression of vimentin taken as a marker of cultured keratinocytes. Histological evaluation was complemented by detection of keratin 10 and involucrin. All three donor sites healed within one week. On day 4 the early neoepidermis was multilayered but disordered after transplantation. A large proportion of cells were apparently of donor origin as indicated by the presence of Y chromosomes, irregular morphology, expression of vimentin in the bottom and upper layers of the neoepidermis, and by irregular expression of involucrin and keratin 10 only in the central layer of the neoepidermis. From day 6 onwards, the new epidermis acquired an ordered stratification. Involucrin and keratin 10 renewed normal distribution in suprabasal layers. Concomitantly, vimentin expression was decreasing. The Y chromosome was still found on day 6 but not on day 9. We concluded that confluent allogeneic keratinocytes temporarily 'take' to the wound and contribute to rapid wound closure, being replaced by the patient's epidermal cells after about one week.

Adult↗
PubMed2001

Necrobiotic process causing burn wound conversion may be prevented by allogeneic keratinocytes delivered by the recombined human/pig skin.

The spontaneous necrobiotic process frequently causes conversion of DDB (deep 2nd degree wounds) into full-thickness skin loss (3rd degree wounds). We found that this process may be positively influenced by the activity of living human allogeneic keratinocytes cultured on acellular pig dermis. This RHPS, if applied 'upside-down' with the epidermal layer facing the wound, provides an opportunity for keratinocytes to influence the healing. The aim of the present study was to find conditions, in terms of timing and wound-bed preparation, for optimum healing activity of RHPS. The wound beds were prepared either with tangential excision, surface dermabrasion or deep dermabrasion. Out of 17 wounds grafted with RHPS after tangential excision, 15 (88%) healed in 4-10 days; early excised wounds (up to day 5) healed within less than 10 days after the injury. Out of 8 wounds grafted after surface dermabrasion, only 2 (25%) healed. Out of 6 wounds grafted with RHPS after deep dermabrasion, 4 (67%) healed. The optimum healing effect of RHPS and prevention of conversion was achieved in early tangentially excised wounds.

Adolescent↗
PubMed2000

Proportion of glomerulosclerosis in procurement wedge renal biopsy cannot alone discriminate for acceptance of marginal donors.

BACKGROUND: The shortage of available kidneys for renal transplantation could be addressed, to some extent, by expanding the criteria for acceptance of marginal donors. The study of these criteria is limited by the selection of grafts actually retrieved and transplanted, therefore reduced to a study of risk factors. We have evaluated the potential of procurement renal biopies as an instrument for acceptance or refusal of donor kidneys for transplantation. METHODS: This was a prospective study of a consecutive series of 200 donors. Biopsies were performed by wedge technique at the donor operation and were evaluated for proportion of glomerulosclerosis, vascular and tubular changes, and interstitial fibrosis. The study included 387 renal grafts with a representative biopsy, transplanted, and followed-up for survival and functional evaluation; 24 hr creatinine clearance at 1 and 3 weeks, and 3, 6, 12, 18, and 24 months. RESULTS: Factors associated with initial graft function included cold ischemia time, number of DR mismatches, tubular changes, although donor age showed the strongest correlation with short- and long-term level of graft function. DR mismatches and retransplantation appeared to be the only significant risk factors for graft loss. The proportion of glomerulosclerosis (mean 8%, range 0-48%) correlated with graft function in the simple regression analysis. However, when age was taken into account glomerulosclerosis did not correlate significantly with graft function. Furthermore, glomerulosclerosis as high as 25% or more had an acceptable 3-year graft survival rate of 74.7%. CONCLUSION: Procurement biopsy provides only limited information for the decision whether or not to accept a kidney donor.

Adolescent↗
PubMed2000

Adverse effect of donor arteriolosclerosis on graft outcome after renal transplantation.

INTRODUCTION: In recent years less strict criteria for renal graft donors have been applied. Our study was designed to investigate whether the histological picture, with special reference to vascular changes of the donor kidney, has an effect on the development and level of graft function, and on 48-month graft survival. METHODS: Three morphologically distinct groups were formed from 150 consecutive cadaveric kidneys donors transplanted into 290 recipients. A control group (C) consisted of kidneys with a completely normal histological picture. Group M1 included kidneys with mild arteriolosclerosis and group M2 (n=122) was comprised of kidneys showing significant arteriolosclerosis. The onset of graft function was assessed by the need for dialysis treatment post-transplantation and the levels of serum creatinine and creatinine clearance at 6, 12, 24 and 36 months post transplant. RESULTS: The proportion of sclerotic glomeruli (P<0.001) and the incidence and severity of interstitial fibrosis was greater in groups M1 and M2 than in the control group (M1, P<0.01; M2, P<0.001). The incidence of vascular fibrinoid necrosis in M2 was greater than in controls (P<0.001). The onset of graft function did not differ significantly between the groups. Group M2 showed a significantly lower level of graft function (P<0.001). The 4-year graft survival rate of group M2 was 74.2%, significantly lower than in the combined group C+M1 (P=0.03). CONCLUSION: Significant vascular lesions in the donor kidney should be taken into account when predicting graft function and survival.

Acute Disease↗
PubMed1998

[Techniques and tactics in multiorgan harvesting].

The eighties and nineties are characterized by potent development of transplantology. Despite this the number of patients with organ failures waiting for a suitable organ is steadily increasing. Due to the permanent shortage of donors transplantation surgery tries to implement the maximum possible multiple organ collection. In the conclusion the authors emphasize the importance of satisfactory cooperation of the anaesthesiologist attending donors and the organ collection teams.

Humans↗
PubMed1998

[Techniques, tactics and organizational aspects of distant procurement of donor hearts for transplantation. Experience at the Department of Cardiovascular and Transplantation Surgery of IKEM with 100 distant procurement of donor hearts].

Transplantation of the heart is currently an accepted therapeutic method. One of the factors which have an adverse effect on its availability is shortage of suitable donors. Distant procurement of hearts helps to extend the number of organs for transplantations. The authors present their experience with distant procurement of donor hearts performed during more than three years. They evaluate the influence of cold ischaemia time of the cardiac graft on early results of cardiac transplantations. In the discussion they try to draw attention to some problems associated with this technique for other organ retrieval teams participating in multiple organ procurement.

Heart Transplantation↗
PubMed1995

[Monocytoid B-lymphocyte lymphoma: a new type within the spectrum of non-Hodgkin's B-cell lymphoma].

BACKGROUND: Clonal proliferation of monocytoid B-lymphocytes (MBLy)--monocytoid B-cell lymphoma (MBCL) represents a "new" type of lymphoma within the spectrum of B-cell malignancies. OBJECTIVES: The aim of the study was to evaluate the possibilities of a routine histological and immunohistochemical diagnosis of MBCL. METHODS: Three cases of MBCL diagnosed in peripheral lymph nodes (n = 2) and in mammary gland with infiltration of regional lymph node (n = 1) were analyzed both histologically and immunohistochemically using a panel approach (Ig chains, CD30 antigen, markers of B-cells, T-cells and of monocytes/histiocytes). RESULTS: Morphological appearance of neoplastic cells of MBCL is identical to that of MBLy in reactive conditions--kidney-shaped nuclei, bright clear PAS-negative cytoplasm, and small inconspicuous nucleoli. CONCLUSIONS: Morphological appearance together with immunophenotypic results (positivity of CD20 and Ki-B5, negativity of CD3, CD43, CD45RO, and of lysozyme, negativity of CD30) are considered to represent sufficient diagnostic criteria of MBCL, including its differential diagnosis of other B-cell low grade malignancies. An increase of large cell type MBLy might represent a feature of a secondary blastic transformation of MBCL. (Tab. 2, Fig. 5, Ref. 27.)

Aged↗
PubMed1994

Actin cytoskeleton and motility in rat sarcoma cell populations with different metastatic potential.

We have studied the organisation of the actin cytoskeleton in three related rat sarcoma cell populations of differing malignancy. They were derived by neoplastic progression from a population which had transformed spontaneously in vitro, and were distinguished by their ability to give rise to reproducibly different numbers of metastases, ranging from 10% to 80% of the animals inoculated. We found characteristic differences in the arrangement of the actin cytoskeleton. Confocal three-dimensional microscopy showed that nearly all of the least malignant population contained conspicuous actin stress fibres lying in the lower part of the cell parallel to the substratum and no other actin structures. Actin in the intermediate population was typically situated in a diffuse layer underlying the whole plasma membrane, in which no fibres could be seen. Two thirds of the most malignant population consisted of more rounded cells filled with a three-dimensional network of fine oblique actin fibres. There were focal contacts in all these cells; their area showed a regular decrease from 1.3 microns 2 to 0.4 microns 2. The differences in actin distribution were accompanied by differences in motility, which increased as malignancy increased. When individual cells were fixed after they had been tracked by time-lapse, their cytoskeleton type correlated with the speed at which they had moved. All these differences were enhanced at low pH. These findings point to the possibility that the three-dimensional network of fine actin fibres in acid culture could be a measure of the malignant potential of transformed cells in vitro.

Actins↗
PubMed1993

[Cryotherapy in retinopathy of prematurity].

Survey of therapeutical and preventive care of premature babies with retinopathy. We observed the children during 10 years (1982-1991). 144 children were cared for various degree of ROP. This number represents 4.5% of unripe babies hospitalized in the pediatric clinic of Faculty hospital in Hradec Králové. The kryopexis was carried out as a model of prevention of ROP in 66 children, where the success arose in 74%.

Cryotherapy↗