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R Popov

Publications and source records attributed to R Popov.

17 recordsLinked to original sources
PubMed2006

Analysis of population differentiation in North Eurasian cattle (Bos taurus) using single nucleotide polymorphisms in three genes associated with production traits.

Single nucleotide polymorphisms (SNPs) in growth hormone 1 (GH1), insulin-like growth factor 1 (IGF1) and leptin (LEP), all candidates for production traits in cattle, were characterized in North Eurasian cattle breeds. Allele frequencies of IGF1 exhibited significant (P < 0.05) deviation from neutral expectation and therefore, might be associated with divergence in North Eurasian cattle because of genetic selection. Allele frequencies and lower heterozygosity of LEP may indicate a recent introduction of an alternative allele in this geographic region. Locus F(ST) estimates were highest for IGF1 (0.151, sigma = 0.042) and lowest for GH (0.062, sigma = 0.020). Our results suggest a slightly higher population differentiation across the candidate genes (FST = 0.108) than across microsatellites (FST = 0.095), possibly because of selection and stochastic effects.

Animals↗
PubMed2003

Cerebellopontine angle meningiomas. Clinical features and surgical treatment.

AIM: The aim of this study is to present the clinical picture of patients with cerebellopontine angle meningiomas and analyze the results of their operative treatment. METHODS: A retrospective study of patients with cerebellopontine angle meningiomas operated consecutively in our department over an 11-year period has been carried out. Data regarding their clinical features, surgical treatment, morbidity, mortality and outcome have been analyzed. Forty-four patients with cerebellopontine angle meningiomas were operated during the period 1991-2001 (intervention: tumor removal via the retrosigmoid suboccipital approach). MAIN OUTCOME MEASURES: clinical condition, MRI/ CT imaging. RESULTS: The median duration of symptoms prior to diagnosis was 44.5 months. The most frequent initial complaints were hearing loss, tinnitus and headache. Most frequent symptoms and signs at presentation were cerebellar, followed by hearing loss and trigeminal nerve symptoms. In 98% of the cases the operative approach used was the retrosigmoidal suboccipital. Total tumor removal was achieved in 55%. After total tumor removal no recurrences have been observed. The mortality rate was 2%. CONCLUSION: The application of different classification schemes complicates the comparison between published series. The outcome depends on their location, consistency, size and relation to the surrounding neurovascular structures. In our experience the retrosigmoid suboccipital approach is most appropriate for their surgical treatment. It offers the possibility to remove completely even large meningiomas and avoids the risk of recurrences.

Adolescent↗
PubMed1997

Differences in dose scheduling as a factor in the etiology of anthracycline-induced cardiotoxicity in Ewing sarcoma patients.

Clinical observation suggested a high prevalence of cardiac morbidity and mortality in children with Ewing sarcoma (ES) treated at B.C.'s Children's Hospital. We therefore compared 30 patients treated for Ewing sarcoma between 1978 and 1991 with 26 soft tissue sarcoma (STS) patients treated with similar chemotherapy over the same period of time. All patients were evaluated for cardiac function using echocardiography. Shortening fraction (SF) and left ventricular mass index (Massl) were compared before and after treatment. The role of chest irradiation, dose concentration (DC) of adriamycin (AD), total mean doses of AD, cyclophosphamide (CY) and actinomycin (AC) were analysed. SF for patients with ES and STS postchemotherapy was significantly lower (P < .001 and P = 0.0004, respectively) than pretreatment values. Postchemotherapy SF for ES was lower than STS (P = 0.0097). Massl for each group did not change significantly. Six of the ES patients had postchemotherapy SF of < 0.20, with three in congestive failure, two cardiac deaths and one heart transplant. One additional ES patient had sick sinus syndrome and needed a pacemaker. Among the STS patients only one had SF < .20 and none were symptomatic. There were no significant differences in the mean AD, CY and AC doses for ES versus STS. The difference in the DC of AD for ES (mean 744) compared to STS (mean = 362) was significant (P = < 0.001). Regression analysis indicated a trend for decreasing SF with increasing DC (P = 0.017). Chest irradiation did not appear to increase the likelihood of cardiotoxicity. ES patients had a higher prevalence of cardiac dysfunction compared to STS. Studies are required to evaluate the importance of the components of DC, i.e., size of the individual dose and frequency of administration of AD, and to look at other possible factors in the causation of cardiomyopathy in ES.

Anthracyclines↗
PubMed1993

[The role and importance of intraoperative cholangiography in modern biliary surgery].

UNLABELLED: The aim of the study is to show that routine use of intraoperative cholangiography may significantly reduce postoperative complications after cholecystectomy. We made a prospective study on 200 cholecystectomized patients in the period IX 1988-III 1989. Patients are divided in two groups: A--control group consisting of 100 cholecystectomized patients without intraoperative cholangiography and B--also consisting of 100 patients with routinely used intraoperative cholangiography. Results are given in the following table where the complications are separated by the time of appearance, specific signs and symptoms. CONCLUSION: Routine use of intraoperative cholangiography significantly reduces the number of complications (A:B = 19:9) which is statistically significant (chi-square test. p < 0.05).

Adult↗
PubMed1992

Rate-corrected mean velocity of fiber shortening-stress at peak systole as a load-independent measure of contractility.

The relation of mean velocity of fiber shortening-stress at end-systole is a good load-independent index of left ventricular contractility, but involves simultaneous M-mode echocardiography, carotid tracing and blood pressure determination, which may be impractical in children. As stress at peak systole and end-systole are closely related, this study examined whether the relation of mean velocity of fiber shortening-stress at peak systole could be used as a simpler method of assessing left ventricular contractility in a normal population of children. In addition, the cross-sectional normal range for a pediatric population was obtained. In 25 normal children aged 4 to 17 years (mean age 11), rate-corrected mean velocity of fiber shortening (MVCFc), stress at peak systole (sigma PS), and end-systolic stress (sigma ES) were determined using echocardiography, carotid pulse tracing and blood pressure measurement. Six patients with cardiomyopathy (mean age 8 years) were also studied. The relation of stress at peak systole and end-systolic stress was sigma PS = 1.004 sigma ES + 12.0 (r = 0.91, SEE = 4.98; p less than 0.001) for the normal group, and sigma PS = 1.083 sigma ES + 7.7 (r = 0.99, SEE = 4.07; p less than .001) for the cardiomyopathic group. This slope of the regression line was slightly higher and the difference was statistically significant. The slope of MVCFc = 0.0066 sigma PS + 1.55 (SEE = 0.131, r = -0.52) was nearly identical to that of MVCFc = 0.0065 sigma ES + 1.46, (SEE = 0.135, r = -0.46), with no difference in the regression coefficients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

Early prediction of anthracycline cardiomyopathy using standard M-mode and digitized echocardiography.

In this study, we attempted to identify echocardiographic findings that can be used as early predictors of left ventricular dysfunction due to anthracyclines in 26 pediatric oncology patients. Retrospective review identified six patients (group 1 mean anthracycline dose = 337 +/- 123 mg/m2) who developed clinical evidence of cardiomyopathy and 20 consecutive patients followed prospectively (group 2 mean anthracycline dose = 298 +/- 102 mg/m2) who did not. All of the patients had serial m-mode echocardiography before and at approximately every 50 mg/m2 of anthracycline treatment depending on the dosage schedule. The following measurements were recorded: left ventricular dimensions and wall thickness, indices of left ventricular function, including systolic time intervals, shortening fraction, and ejection fraction. Using digitized echocardiography, the following parameters were recorded: peak and normalized systolic and diastolic velocities of the left ventricular chamber, posterior and septal wall velocities, and percent of posterior wall thickening. Variations from established normal longitudinal bounds and actual changes from pre-anthracycline values were compared for the two groups throughout the course of therapy. At 70 mg/m2 of anthracycline, group 1 showed significant deterioration in shortening fraction (mean change = 8.8 versus 2.5, p = .03), left ventricular velocity in diastole (2.9 versus 0.21, p = .04), left ventricular normalized velocity in systole (.65 versus 0.03, p = .02), and left ventricular normalized velocity in diastole (1.15 versus 0.002, p = .04) compared to group 2. These values were mostly compensated by 125 mg/m2, but they slowly deteriorated again at higher doses of anthracycline, leading to the appearance of clinical evidence of cardiomyopathy.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1991

Doppler-derived mean aortic flow velocity in children: an alternative to cardiac index.

This study tested the hypothesis that mean aortic velocity is relatively constant in children. Eighty-eight normal children (aged 1 month to 15 years) were studied prospectively. Ascending aortic flow velocities were obtained by pulse Doppler and mean aortic velocities calculated. Mean aortic flow velocity was relatively constant for all ages at 28.4 +/- 4.8 cm/s. As Doppler is easy to perform, mean aortic flow velocity may be an alternative approach to the assessment of cardiac output.

Adolescent↗
PubMed1991

[Shock and acute kidney failure because of not taking fluids].

A case is presented of shock and acute renal failure due to dehydration in a woman with a psychic disease who had not taken food and fluids for a long time. The post mortem examination revealed the pathomorphologic pattern of shock with microthrombi in the inner organs, brain and leptomeninges.

Acute Kidney Injury↗
PubMed1987

Left ventricular systolic and diastolic function after total correction of tetralogy of Fallot.

Left ventricular (LV) systolic and diastolic function was assessed in 12 patients after total correction of tetralogy of Fallot (age range 5 to 18 years, mean 10) and compared with 10 control patients. Only 1 patient had a shunt before total correction that was performed at a mean age of 3.5 years, (range 0.3 to 8). At cardiac catheterization the following indexed LV parameters were measured: end-diastolic and end-systolic volumes, wall mass, ejection fraction, stroke volume and end-diastolic and end-systolic pressures and stresses. The rate-corrected mean velocity of fiber shortening was calculated. LV diastolic operant chamber stiffness and myocardial stiffness were calculated from simultaneous diastolic pressures and volumes in mid- and late diastole using monoexponential formulas. The 2 groups were compared by unpaired t tests. The tetralogy group had higher mean end-diastolic (93 vs 74 ml/m2), end-systolic (29 vs 19 ml/m2) and stroke (64 vs 55 ml/m2) volumes than controls. Rate-corrected mean velocity of fiber shortening was lower in the tetralogy group (1.07 vs 1.24). Myocardial stiffness was higher in the tetralogy group (16 vs 11). Other indexes were not significantly different. Thus, LV function after total correction of tetralogy of Fallot may be abnormal with larger than normal LV size, decreased contractile function and increased myocardial stiffness.

Adolescent↗
PubMed1987

Normal serial variability for M-mode and digitized echocardiography in a pediatric population.

The normal serial variability of M-mode and digitized echocardiography was assessed in 18 healthy children aged 3-16 years. M-mode echocardiograms were done one month apart in each child and two sets of three beats were analyzed twice for each month's tracing. Ejection fraction and shortening fraction were obtained in the standard manner and the tracing digitized and analyzed for peak and normalized left ventricular velocities, and for posterior wall and septal wall velocities in systole and diastole. The component variabilities were determined by a univariate four-factor hierarchical variance components analysis and the sum of these variability limits established. Standard M-mode echocardiographic measurements of shortening fraction and ejection fraction (15% and 10% of mean) were the least variable. Peak and normalized velocities were more variable with left ventricular velocities (18%-29% of mean), posterior wall velocities (26%-45% of mean) and septal velocities (38%-68% of mean) showing increasing variabilities. Thus there is less variability in M-mode echocardiography than digitized echocardiography. The normal limits of variability are established and should be used for follow-up studies.

Adolescent↗
PubMed1987

[Treatment with superhigh corticosteroid doses (pulse therapy) of patients with the idiopathic nephrotic syndrome].

The results from the pulse therapy of 11 patients with severe nephrotic manifestations of idiopathic nephrotic syndrome are summarized, that had failed to respond to the preceding conventional corticosteroid treatment. Rapid improvement was attained in nine of the patients studied. Best were the results in the patients with "minimum" morphological alterations and with diffuse mesangial proliferation. Favourable effect was obtained also in the patients with glomerular sclerosis and hyalinosis. The failure of treatment in one of the female patients with mesangial proliferation is associated with the adverse unfavourable factors, and in one of the male-patients with glomerular sclerosis and hyalinosis--with severe morphological changes and exhausted functional potentialities of kidneys. The authors admit that the fast favourable effect by the therapeutic schedule used, make it a means of choice in forms of idiopathic nephrotic syndrome with a grave course and failing to respond to the routine treatment.

Cyclophosphamide↗