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K Krejcí

Publications and source records attributed to K Krejcí.

17 recordsLinked to original sources

Changes in bone mineral density and selected metabolic parameters over 24 months following renal transplantation.

Our aim was to evaluate changes in serum levels of selected bone metabolism indicators and bone density over 24 months following renal transplant. A partial objective was assessment of the effectiveness of prophylactic administration of vitamin D and calcium preparations to prevent progression of osteopathy after kidney transplantation. Forty patients after kidney transplantation were prophylactically given vitamins A and D (800 IU) and calcium (1000 mg) a day. During monitoring, the serum creatinine in all recipients was <200 micromol/L (subgroup A with creatinine concentration < 120 micromol/L versus subgroup B with creatinine 120 to 200 micromol/L). The concentration of serum parathormone, serum level of bone fraction of alkaline phosphatase, serum concentrations of phosphorus and calcium urinary 24-hour excretion of phosphorus and calcium were examined at 2 weeks and 2 years after transplantation. In the same time period, radiographs of thoracic, lumbar spine, and hip joints were obtained. Bone density (BMD) of the lumbar (L) spine and the hip was determined by dual-energy X ray (Lunar Prodigy). Two years after transplantation in subgroup A, the BMD showed decrease in 80% of recipients in the L spine area but hip showed a 15% BMD increase. In subgroup B, the BMD decreased in 95% recipients in L and hip and only 25% showed a BMD increase. No clinical or radiographic sign of fracture was detected in this group. We conclude that prophylactic administration of vitamin D and calcium is not sufficient to prevent the progression of osteopathy after renal transplantation. Changes in bone density evaluated after the kidney transplantation are affected by graft function.

Adult↗

[Fibrillary glomerulonephritis--a rare cause of nephrotic syndrome].

Fibrillary glomerulonephritis (FGN) is a rarely diagnosed disease with clinical manifestations such as proteinuria, microscopic hematuria, nephrotic syndrome or decreased kidney function. Around one half of patients develop chronic renal failure in the course of several years. The diagnosis of fibrillary glomerulonephritis is to be established only basing on the results of renal biopsy. Pathognomonic is the electron-microscopic examination, evidencing fibrillar deposits in mesangium and in basal membranes of glomeruli. Fibrils are similar to those seen at amyloidosis, however, with larger diameter, non-linear deposition and do not stain with Congo red or thioflavin T. Immunofluorescency test usually shows the presence of IgG, namely the subclasses IgG4, C3 and kappa and lambda of light immunoglobulin chains. The presented case report describes clinical and laboratory findings at a patient suffering from nephrotic syndrome. Results of renal biopsy and detailed histological examinations concluded the diagnosis as fibrillary glomerulonephritis. The patient was treated with a combination of prednisone (1 mg/kg/24 hrs) with cyclophosphamide (2 mg/kg/24 hrs) for six months. This led to a decrease of proteinuria from the initial value of 5.38 g/24 hours to 1.88 g/24 hours, as well as to a partial remission of nephritic syndrome. Glomerular filtration, evaluated using endogenous creatinine clearance, remained within limits of normal values throughout the follow-up, with the value of 2.6 ml/s after the treatment.

Glomerulonephritis↗

[Histologic findings in protocol biopsies of transplanted kidneys].

Fourty eight patients with cadaveric kidney allografts treated by cyclosporin A (CSA) or tacrolimus (FK506) underwent protocol graft biopsies at 1, 3 and 12 months after transplantation, and 110 biopsy specimens were obtained. Histologic diagnosis was made according to the Banff scheme. The main cause of the graft instability at 1 and 3 months was acute clinical rejection, these biopsies showed all known histological patterns of tubulointersticial and vascular rejection. Acute tubular nephropathy was found in 13% and borderline changes or nephrotoxicity in 8.7% of instable grafts. Specifically, we focused on the occurRence of subclinical rejection and toxic reactions in stable renal allografts. Of these, 36.1% showed histological patterns of acute tubulointersticial and vascular rejection. The Banff score of subclinical rejection was significantly lower than in clinically apparent rejection. CSA and tacrolimus nephrotoxicity were seen in 14.2%, 19.5% and 27.2% of specimens at 1, 3 and 12 months, respectively. In over one half of the identified cases of nephrotoxicity neither increased level of immunosuppression nor features of allograft dysfunction were found. At 12 months, 45.5% of specimens showed mild chronic transplant nephropathy and 18.1% moderate chronic transplant nephropathy. Normal morphology was found in 36.4% of biopsies. We found a high prevalence of subclinical rejection and nephrotoxicity in the studied cohort. We conclude that protocol biopsy is a reliable method in the diagnosis of clinically silent, as well as clinically apparent, disorders of the transplanted kidney.

Biopsy, Needle↗

[Arteriovenous fistula as a complication of renal biopsy].

Renal biopsy is nowadays considered a relatively safe and routine examination method in nephrology. Its development was made possible by extension of sonography and introduction of modern automatic bioptic sets. Relatively frequent complications of biopsy include macrohaematuria, perirenal haematomas and AV fistulae. The majority of complications is unimportant from the clinical aspect. Some 30% fistulae do not recede spontaneously and gradual remodelling of the circulation near the fistula may lead to the development of complications. In the submitted paper the authors inform on the case of a 55-year-old woman where 24 hours after biopsy of a renal graft a sonographically revealed arteriovenous fistula closed spontaneously within one month; the case of a 40-year-old woman where 5 days after biopsy progression of a subcapsular haematoma and manifestation of a fistula occurred, and a 35-year-old man who developed 6 years after biopsy gradually an arteriovenous fistula with uncontrollable hypertension, hypercirculation syndrome and functional deterioration of the transplanted kidney. Superselective embolization led to improvement of the circulatory sequelae of the vascular shunt but did not have a favourable impact on renal function. Analysis of hitherto assembled experience indicates that direct ultrasound control of biopsy is effective. Because the manifestation of possible complications of biopsy need not follow immediately after the operation ultrasound follow up of native and transplanted kidneys after biopsy is justified even after a longer time interval after the operation.

Adult↗

[Subclinical rejection of kidney transplants and the possibilities of its diagnosis].

RESOURCE: The subclinical rejection is defined as finding of histological signs of rejection on well functioning grafts. Its diagnostic domain remains protocol biopsy. The diagnostic value of ultrasound scaning in subclinical rejection has not been studied yet. AIM: The aim of our study was to detect the incidence of subclinical rejection in protocol biopsies in the first three months after kidney transplantation and to find out the ultrasound correlation to histological picture of subclinical rejection with special accent on ultrasound signs of parenchymal oedema, quantity and quality of perfusion emphasising their changes in process of time. METHODS: Sixty six protocol graft biopsies were performed on 36 recipients of cadaveric renal transplants in Transplant Centrum Olomouc between July 1999 and September 2000. The biopsies were carried out 21 +/- 2 days and 90 +/- 5 days after transplantation. Subclinical rejection was defined as t2 i2 v0 (IA) rejection infiltrate by Banff 97 histological classification at the same time with serum creatinine in normal range and ultrasound signs of parenchymal oedema. RESULTS: In the group of subclinical rejection the ultrasound findings of graft parenchymal oedema correlated with 81% sensitivity and 90 % specificity with histological diagnosis. The duplex picture of parenchymal hyperaemia blush - had 100 % specificity but low sensitivity. The resistive indices were in the wide range 0,61 - 0,80 without diagnostic value. CONCLUSION: The high sensitivity and specificity of ultrasound prospective follow up was found in the subclinical rejection diagnosis. Parenchymal hyperaemia indicated high specificity but low sensitivity in evaluation of subclinical rejection. No benefit of resistive indices was found. Larger sample of patients has to be established to gain more exact review anyway.

Adult↗

Telomerase activity and expression and telomere analysis in situ in the course of treatment of childhood leukemias.

Samples of blood and marrow from children with leukemia were assayed for telomerase activity and expression on the day of diagnosis and during the course of chemotherapy. A strong correlation between either variables and clinical response was observed in most patients. A unique case was observed in which telomerase activity was only moderately increased on diagnosis; it gradually increased in the course of therapy, and a subsequent decrease occurred only after application of intensified therapy. This patient did not respond to therapy, his disease progressed, and he finally died during intensified therapy. In another patient, analysis of telomere lengths using dideoxy-PRINS revealed a single telomere expansion on a long arm of chromosome 4, suggesting involvement of a telomerase-independent mechanism of telomere elongation.

Acute Disease↗

[Dual-photon bone densitometry in dialyzed patients].

In non-invasive diagnosis of renal osteodystrophy the levels of bone minerals and the extent of bone turnover are evaluated. The contents of bone minerals are assessed quantitatively by different modalities of bone densitometry, among which the most accurate one is double-energy bone densitometry. So far no standard examination method was defined nor the most suitable portion of the skeleton for densitometric examination. In order to find such an area and also to assess the prevalence of bone demineralization, its severity and regional differences the authors made a cross-sectional study of bone density in dialyzed patients. The group comprised 45 patients, 24 men and 21 women subjected to regular dialyzation treatment for 20-24 months. In a lambda whole body bone densitometry was performed with evaluation of regional densities of the trunk, upper and lower extremities. At the same time the state of bone turnover was assessed arbitrarily using values of serum concentrations of intact parathormone; parathormone concentrations below 50 pg/ml were considered low, above 200 pg/ml high and concentrations within the mentioned range as the normal bone turnover. In the group of patients 62% had a high, 22% a normal and 16% a low bone turnover. The study provided evidence of a significant reduction of bone density (Z score <-1) in 58% of patients. In 92% of patients demineralization affected most and first the extremities. In 69% it affected the lower extremities and in 23% the upper ones. 8% of the patients had the most severe affections in the area of the trunk. This order of affliction was not influenced by bone turnover, sex and in women by age. The diaphysis of long bones seems to be a representative examination area of the skeleton for densitometric measurements in patients with regular dialyzation treatment.

Absorptiometry, Photon↗

An in situ study of variant telomeric repeats in human chromosomes.

Variant telomeric repeats are selectively detected in human telomeres in situ by the novel approach of dideoxy-PRINS, displaying their organization in a format where all the individual chromosome ends can be viewed individually and simultaneously. All human chromosome ends are found to contain variant repeats, though not all types of repeats can be detected on all chromosome ends. Although the staining frequency at particular chromosome ends seems polymorphic among individuals, some chromosome ends are more commonly stained with a given probe than others. A few chromosome ends also appear with particularly strong signals. With a probe for one type of variant repeat ((AGGGTG)n), peculiar patterns with more than two signals per chromosome end are observed.

Humans↗

Molecular cytogenetics investigation of the telomeres in a case of Philadelphia positive B-ALL with a single telomere expansion.

We have investigated a single telomere expansion in a case of acute lymphoblastic B-cell leukemia (B-ALL), where half of the cells in the bone marrow sample appeared with a Philadelphia chromosome. Comparing telomere sizes in Philadelphia-positive versus -negative cells, we found generally shorter telomeres in the Philadelphia-positive cells, but with an expansion of the telomere on the long arm of one chromosome 11 homologue. This expansion was also found in a minority of Philadelphia-negative cells. The telomeres in these cells were of the same overall size as the telomeres in the Philadelphia-negative cells without the 11q expansion. Together, these findings suggest that the order of events was: 11q telomere expansion, Philadelphia translocation, overall telomere shortening. The expanded 11q telomere contained the standard telomeric (AGGGTT)(n) repeat, but also variant repeat sequences. The single telomere expansion suggests a non-telomerase mechanism behind the expansion which may also explain the presence of variant repeats in the expanded telomere. The present case illustrates that telomere changes may occur at only some chromosome ends in a subset of cells. To reveal such changes, telomere morphology should be studied with in situ methodology.

Adult↗

Telomeric repeat organization--a comparative in situ study between man and rodent.

Human, hamster, and mouse chromosomes show both similarities and differences in telomeric organization, detectable with a novel version of the PRINS technique. The differences allowed us to investigate the fate of the telomeres on a chromosome from one species when this chromosome was introduced into the cells of another species. For this purpose, we tested telomeres in cell lines of somatic cell hybrids containing human chromosomes on a rodent background, finding that the telomeres on human chromosomes could not be discriminated from the telomeres on rodent chromosomes. All telomeres in the cell lines were much shorter than the telomeres in normal cells. In the mouse-derived cell lines, half of the mouse chromosomes were fused to other mouse chromosomes at the ends of their short arms. At the points of fusion we were generally unable to detect telomeric signals. In these cell lines, we also found a fraction of chromosomes ends with only one telomeric signal. In chromosomes where both ends showed only one signal, the relative orientation of the signals appeared to be nonrandom with respect to sister chromatids.

Animals↗

Selected prognostic factors of long-term renal graft function.

Kidney transplantation is a method of choice as a treatment for end-stage renal disease in indicated cases. However, the long graft survival represents only about 50% due to various types of rejection as a leading cause of graft loss in renal transplant recipients. The early dg. of rejection and especially acute rejection, it's adequate management, decreased risk for the future chronic rejection nephropathy. This is a primary goal of the clinician caring for these patients. We use several methods in order to make diagnosis of acute rejection. Urine cytology and urine flow cytometry have been found highly sensitive specific for the early diagnosis of acute rejection, provide us useful information in differentiation from others causes of graft dysfunction. Urine analysis have some advantage over other diagnostic methods and can facilitate the observation of a graft over time.

Graft Rejection↗

[Hematologic findings and value of value of endogenous creatinine in patients following kidney transplantation].

We have studied serum erythropoietin (EPO) levels, serum creatinine and blood hemoglobin and hematocrit levels in the group of 140 patients after kidney transplantation. All patients received conventional immunosuppressive therapy consisting of cyclosporine (Sandimmune Neoral), azathioprin (Imuran) and steroids (Prednison). The aim of the study was to investigate the relationship between serum EPO, serum creatinine and hematologic parameters. Complete restoration of hemoglobin and hematocrit levels was obtained in 99 patients (70.7%), moderate degree of anaemia with average hemoglobin level 114.7 +/- 12.3 g/l was seen in 37 patients (26.4%) and four patients (2.9%) had posttransplant erythrocytosis. Normal hemoglobin values are generally restored during 3 months after successful renal transplantation. Statistical analysis confirmed significant correlation (p < 0.001) between graft function and hematologic parameters, but none correlation was found neither between serum EPO levels and serum creatinine and not between serum EPO levels and hemoglobin/hematocrit values. Plasma creatinine is not reliable indicator of renal EPO secretory capacity. The degree of correction of anemia is limited by the stage of graft function and correlates with the serum creatinine concentration. The results suggest, that the restoration of normal excretory graft function after transplantation improves bone marrow response to EPO and leads to normalization of erythropoietic activity.

Adult↗

Single photon bone densitometry in hemodialysis patients.

Renal osteodystrophy is a common finding in patients with renal insufficiency. The maximum of its intensity is found in hemodialysis patients. Bone densitometry is so far the best method for non-invasive assessment of the extent of the illness. Some densitometric studies in hemodialysis patients have already been published but their results differ in prevalence and intensity of renal osteodystrophy. They also demonstrated a slight relationship between intensity of renal osteodystrophy and duration of the dialysis treatment. Opinions vary on the relationship between bone mineral density and markers of bone turnover. This cross-sectional study found high prevalence of renal osteodystrophy (Z-score below -1 in 57% of patients) as well as high a number of severely damaged patients (T-score below -2.5 in 40% of patients). It also showed some correlation between bone demineralisation and the duration of dialysis. None from evaluated markers of bone turnover correlated with bone mineral density.

Absorptiometry, Photon↗

Improved detection and comparative sizing of human chromosomal telomeres in situ.

Telomeric length dynamics are thought to play an important role both in the processes of cellular aging and cancer progression. We have revised the primed in situ (PRINS) labeling technique to allow an estimation of the relative length of individual telomeres. We illustrate the applicability of the approach by demonstrating different telomeric sizes not only between blood lymphocytes from a young and an old donor, but also among bone marrow cells from hematological cancer patients. In the latter case we found general variations in telomeric sizes as well as individual telomeric variations that would have escaped detection by other methods. An interesting finding was the selective expansion of a single telomere within a specific subset of cells.

Adolescent↗