Proclination-induced changes in the labial cortical bone thickness of lower incisors.

OBJECTIVES: We sought to objectivize the overall alveolar bone thickness changes in lower incisors after orthodontic intervention. BACKGROUND: The effect of orthodontic treatment on the cortical bone, specifically the clinical implications of proclination-induced change, have long been a matter of dispute. METHODS: Cone-beam computed tomographs of 58 patients were obtained before and after treatment and labial cortical bone thickness and overall alveolus width were measured in sagittal sections in the distance of 3, 6, 9 and 12 mm apically from the cemento-enamel junction. RESULTS: A statistically significant decrease of the cortical bone thickness in all four incisors was found at the levels 3, 6 and 9 mm (p 0.05). Moreover, no correlation was found between bone thickness change and extent of the incisor movement. CONCLUSION: Our results point to a marked cortical bone loss after proclination of lower incisors, furnishing a sound basis for caution in treatment planning due to the considerable risk of alveolar defect development, especially in patients with low initial bone thickness (Tab. 6, Fig. 2, Ref. 25).

[Transplantation of allogeneic bone graft in the therapy of massive post-sternotomy defects - 6 years of experience with the method]. / Transplantace allogenního kostního stepu v lécbe rozsáhlých post-sternotomických defektu - 6 let zkuseností s metodou.

INTRODUCTION: Early complications due to deep sternal wound infection pose a serious problem in cardiac surgery, with an up to 40% risk of mortality. Massive loss of sternum bone tissue and adjacent ribs results in major chest wall instability difficult to resolve using classical AO osteosynthesis procedures, causing respiratory insufficiency making the disconnection from artificial pulmonary ventilation difficult, and additional defects of soft tissue healing. Based on orthopaedic experience with bone defect replacement, we used the allogeneic bone graft method to reconstruct the chest wall. METHODS: In the period of 20112015 we performed the transplantation of an allogeneic bone graft in 13 patients. In 10 cases, an allograft of the sternum was used, in one case an allograft of the calva bone and in two cases the crushed spongy bone was used. After primary cardiac surgery, a massive post-sternotomy defect of the chest wall developed in all the 13 patients due to deep sternal infection and osteomyelitis of the sternum and adjacent ribs. Vacuum wound drainage was applied in the treatment of all the patients. To stabilize the chest and the graft, transverse titanium plates were used, fixed using bicortical screws. The bone allograft was prepared by the official Tissue Centre. Crushed allogeneic spongy bone was applied to reinforce the line of contact of the graft and the edges of the residual skeleton. In 12 cases, the soft tissue was closed by direct suture of mobilized pectoral flaps. In one case, V-Y transposition of the pectoral flap was performed. RESULTS: In 8 cases, healing of the reconstructed chest wall occurred without further complications. In 4 cases, additional re-suture of soft tissues and skin in the lower pole of the wound was needed while the patients were still in the hospital. However, excellent chest wall stability along with adjustment of respiratory insufficiency and a very good cosmetic effect in the wound were achieved in all the 12 cases. In two cases, explantation of the plates was required. In one case, severe concomitant complications and no healing of the wound resulted in death within half a year after the reconstruction. The median follow-up period of all patients in the series was 21 months (136). In 5 cooperating patients, scintigraphy of the chest wall was performed repeatedly during the follow-up period showing a high healing activity of the graft and particularly of the crushed spongy bone. CONCLUSION: Our existing results show that allogeneic bone graft transplantation is a promising and easily applied method in the management of serious tissue loss in sternal dehiscence with favourable functional and cosmetic effects.Key words: sternotomy deep sternal wound infection massive post-sternotomy defect allogeneic bone graft.

Contemporary skull development - palatal angle analysis.

OBJECTIVES: The palatal angle is an important angle of the craniofacial complex. It is significant for the diagnosis of craniofacial disorders mainly for nasopharyngeal soft-tissue patterns.Background The dentists and otorhinolaryngologists use this relationship to establish proper treatment mechanics and evaluate facial profile. The aims of this study were to provide comparative cephalometric analyses of historical and contemporary skulls. MATERIALS AND METHOD: A total of 190 cephalograms of 2 groups of subjects were evaluated. Dolphin Imaging 11.0 - Cephalometric Tracing Analysis was used for the analysis. Unpaired two-tailed t-test assuming equality of variances was used for all variables (at the significance level p = 0.0001). RESULTS: The -modern forensic skulls had larger palatal angle at average value of 8.60 degrees ± 4.35, than that of archeological ones, the average value of which was 6.50 degrees ± 3.92. The difference was found significant. Unpaired two-tailed t-test assuming equality of variances showed that historical and contemporary skulls had statistically significant results. The difference was -2.09 with standard error of 0.60 (95% confidence interval from -3.29 to -0.89). Two-tailed probability attained value of P was less than 0.0001. CONCLUSION: The difference between both groups was found significant. An increase in the palatal angle can be directly connected with anterior rotation of upper jaw(Tab. 2, Fig. 5, Ref. 19).

Reliability of the cervical vertebrae maturation (CVM) method.

OBJECTIVE: To assess the reliability of the cervical vertebrae maturation method (CVM). BACKGROUND: Skeletal maturity estimation can influence the manner and time of orthodontic treatment. The CVM method evaluates skeletal growth on the basis of the changes in the morphology of cervical vertebrae C2, C3, C4 during growth. These vertebrae are visible on a lateral cephalogram, so the method does not require an additional radiograph. METHODS: In this website based study, 10 orthodontists with a long clinical practice (3 routinely using the method - "Routine user - RU" and 7 with less experience in the CVM method - "Non-Routine user - nonRU") rated twice cervical vertebrae maturation with the CVM method on 50 cropped scans of lateral cephalograms of children in circumpubertal age (for boys: 11.5 to 15.5 years; for girls: 10 to 14 years). Kappa statistics (with lower limits of 95% confidence intervals (CI)) and proportion of complete agreement on staging was used to evaluate intra- and inter-assessor agreement. RESULTS: The mean weighted kappa for intra-assessor agreement was 0.44 (range: 0.30-0.64; range of lower limits of 95% CI: 0.12-0.48) and for inter-assessor agreement was 0.28 (range: -0.01-0.58; range of lower limits of 95% CI: -0.14-0.42). The mean proportion of identical scores assigned by the same assessor was 55.2 %(range: 44-74 %) and for different pairs of assessors was 42 % (range: 16-68 %). CONCLUSIONS: The reliability of the CVM method is questionable and if orthodontic treatment should be initiated relative to the maximum growth, the use of additional biologic indicators should be considered (Tab. 4, Fig. 1, Ref. 24).

Pilot study of A-FABP levels as a predictive factor of SPECT results in asymptomatic relatives of patients with cardiovascular disease.

BACKGROUND: A-FABP is a promising link between metabolic syndrome and atherosclerosis. It is not well known whether level of A-FABP predicts results of SPECT. PATIENTS & METHODS: In 82 subjects (53 males) with a median age of 54 years, who were first-degree relatives of patients with cardiovascular disease, the following tests and examinations were performed: A-FABP, calcium score (CS) and SPECT. RESULTS: Subjects with positive and negative SPECT results differed significantly in the noncategorized CS (p = 0.001), uric acid (p = 0.025) and the total cholesterol:high-density lipoprotein ratio (p = 0.043), but not in other parameters (including A-FABP). To predict SPECT results, the best model proved to be a logistic regression model with gender and noncategorized CS as predictors, with an area under the receiver operating characteristic curve of 0.89 (the sensitivity and specificity based on a CS cutoff of 11.1 were 77.78 and 75.34%, respectively). CONCLUSION: The serum level of A-FABP is not a predictor of a positive SPECT result.

Nasolabial appearance after two palatoplasty types in cleft lip and palate.

BACKGROUND: Facial appearance is important for normal psychosocial development in children with cleft lip and palate (CLP). There is conflicting evidence on how deficient maxillary growth may affect nasolabial esthetics. METHODS: We retrospectively investigated nasolabial appearance in two groups, the Langenback (35 children; mean age 11.1 years; range: 7.9-13.6) and Vomerplasty (58 children; mean age 10.8 years; range: 7.8-14), who received unilateral CLP surgery by the same surgeon. The hard palate repair technique differed between the two groups. In the Langenback group, palatal bone on the non-cleft side only was left denuded, inducing scar formation and inhibiting maxillary growth. In the Vomerplasty group, a vomerplasty with tight closure of the soft tissues on the palate was applied. Thirteen lay judges rated nasolabial esthetics on photographs using a modified Asher-McDade's index. RESULTS: Nasolabial esthetics in both groups was comparable (p > 0.1 for each nasolabial component). Inferior view was judged as the least esthetic component and demonstrated mean scores 3.18 (SD = 0.63) and 3.13 (SD = 0.47) in the Langenback and Vomerplasty groups, respectively. Mean scores for other components were from 2.52 (SD = 0.63) to 2.81 (SD = 0.62). Regression analysis showed that vomerplasty is related with slight improvement in the nasal profile only (coefficient B = -0.287; p = 0.043; R(2 ) = 0.096). CONCLUSIONS: This study demonstrates that the use of vomerplasty instead of the Langenbeck technique is weakly associated with the nasolabial appearance among pre-adolescent patients with UCLP.

[Is there dependence between the level of adipocyte fatty acid-binding protein and calcium score in asymptomatic relatives of patients with cardiovascular diseases?]. / Existuje závislost mezi hladinou adipocyte fatty acid binding proteinu a kalciovým skóre u asymptomatických príbuzných pacientu s KVO?

UNLABELLED: The objective of our study was to determine a correlation between the level of adipocyte fatty acid-binding protein (A-FABP) (as a possible link between metabolic syndrome and atherosclerosis), the calcium score (CS) and laboratory parameters, including insulin resistance indices in asymptomatic first degree relatives of patients with cardiovascular diseases. SET AND METHODOLOGY: Examination was conducted in 82 persons (53 male) with the average age of 52.79 ± 9.6. The examinations consisted of anthropometric and physical tests (determination of body weight, height, body mass index - BMI and casual blood pressure measurement), laboratory analysis (uric acid, creatinine, lipid panel, insulin, glucose, C-reactive protein, fibrinogen, glycated hemoglobin, adipocyte fatty acid-binding protein - A-FABP) and determination of insulin resistance indices HOMA and QUICKI. Total calcium score (CS) was determined by the Agatston method without the need to administer a contrast agent. RESULTS: The value of the A-FABP level does not show a statistically significant dependence on the categorised CS or on non-categorised CS values. There is a statistically significant positive dependence of the level of A-FABP on the HOMA index (p = 0.00688) and a statistically significant negative dependence on the QUICKI index (p = 0.0068). The A-FABP level is statistically significantly higher in women (p = 0.048), in elder persons (p = 0.043), and in persons with higher BMI values (p = 0.029). Among continuous variables, statistically significant is the difference in the A-FABP level in relation to age (p = 0.002), creatinine (p = 0.026), insulin (p = 0.005), and BMI (p = 0.031). CONCLUSION: Our study confirmed the correlation of the A-FABP level with insulin resistance indices, BMI, age, gender, and insulin and creatinine levels in a group of asymptomatic first degree relatives of patients with cardiovascular diseases. A-FABP could potentially be a marker when determining the risk of CVD; however, this conclusion requires additional clinical trials.

Fiber-optic pH detection in small volumes of biosamples.

Determining the pH values of microscopic plant samples may help to explain complex processes in plants, so it is an area of interest to botanists. Fiber-optic probes with small dimensions can be used for this purpose. This paper deals with the fiber-optic detection of the pH values of droplets of plant xylem exudate based on ratiometric fluorescence intensity measurements with an internal reference. For this purpose, novel V-taper sensing probes with a minimum diameter of around 8 µm were prepared that enable the delivery of fluorescence signal from the detection site on the taper tip to the detector. The taper tips were coated with pH-sensitive transducer (8-hydroxypyrene-1,3,6-trisulfonic acid trisodium salt; HPTS) and a reference [dichlorotris-(1,10-phenanthroline) ruthenium (II) hydrate (Ru-phen dichloride)] immobilized in a xerogel layer of propyltriethoxysilane and (3-glycidoxy)propyl trimethoxysilane. The prepared probes were sensitive to pH values mainly in the range from 6.0 to 9.0. In the pH range 6-9, the results were limited by measurement errors of about 0.2 pH units, and in the pH range 5-6 by measurement errors of about 0.5 pH units. Using the developed V-taper sensing probes, the pH values of in vivo and in vitro samples of small volumes (~6 µl) of exudate were measured. The results were validated by comparison with conventional electrochemical pH measurements.

Association of polymorphisms of zinc metalloproteinases with clinical response to stem cell therapy.

AIM: The purpose of this study was to assess the associations of polymorphisms in two metalloproteinase genes-metalloproteinase-2 (MMP-2) and angiotensin converting enzyme (ACE)-with clinical response to autologous transplantation of mononuclear bone marrow cells (MBMC) in patients with acute myocardial infarction. METHODS: The double centre study included 48 patients with a first acute myocardial infarction treated with primary coronary angioplasty, stent implantation and transplantation of MBMC. According to the changes in perfusion defect size, left ventricle ejection fraction, end-systolic volume and peak systolic velocity of the infracted wall (dSaMI) after cell therapy, the patients were retrospectively divided into group A (responders) and group B (non-responders). Genomic DNA was isolated from peripheral leukocytes by a standard technique using proteinase K. Three MMP-2 promoter (-1575G/A, -1306C/T and -790T/G) as well as I/D ACE gene polymorphisms were detected by PCR methods with restriction analyses (when necessary) according to standard protocols. RESULTS: Of the 48 patients who received MBMC transplantation, 17 responded to the therapy. There were no significant differences in the prevalence of matrix metalloproteinase-2 triple genotype GGCCTT between responder/non-responder groups (71% versus 61%, p=0.375). Similarly, no differences in either genotype distribution or allelic frequencies of I/D ACE polymorphism between responders and non-responders to the cell therapy were observed (p=0.933). Compared to patients with ACE genotype ID or DD, the patients with ACE II genotype significantly improved in regional systolic LV function of the infarcted wall after implantations of MBMC (dSaMI - 0.4 versus 1.4 cm/s, p=0.037). CONCLUSION: In our study, the ACE genotype II was associated with improvement of regional systolic LV function of the infarcted wall after implantations of MBMC. The detected polymorphism in matrix metalloproteinase-2 gene was not associated with clinical response to cell therapy.

[Risk stratification by cardiac gated SPECT combined with coronary artery calcium score in patients with diabetes mellitus and/or renal failure]. / Stratifikace rizika pomocí zátezového SPECT zobrazení myokardu v kombinaci se stanovenim koronárního kalciového skóre u rizikových pacientu s diabetem a/nebo ledvinným selháním.

AIM: The aim of this study was to evaluate added value of coronary artery calcium score (CAC) measurement as an adjunct to cardiac gated SPECT for risk stratification in population of patients with diabetes mellitus (DM) and/or chronic renal failure on hemodialysis (CHRF-HD). METHODS: Retrospective analysis of 67 patients, who were referred for stress gated myocardial perfusion SPECT and CAC. Characteristics of study population: 40 men, mean age 59 +/- 12 years, DM (n = 28), CHRF-HD (n = 22), DM and CHRF-HD simultaneously (n = 17). Perfusion summed stress and different scores (SSS, SDS), the left ventricle ejection fraction (LVEF) and enddiastolic/endsystolic volumes (EDV/ESV) were automatically calculated using 4D-MSPECT software. The hard cardiac event was defined as sudden cardiac death or myocardial infarction (MI); angina or other symptoms requiring coronary revascularization were also calculated. RESULTS: During the average period of 18 +/- 10 months, we registered 8 cardiac deaths, 4 nonfatal MI and 7 patients underwent revascularization. In the subgroup of 19 patients with cardiac events, the observed parameters were significantly worse concerning perfusion (SSS 9 +/- 11 vs 2 +/- 3 and SDS 6 +/- 9 vs 1 +/- 2, P < 0.05), the left ventricle function (stress LVEF 53% +/- 13% vs 59% +/- 13%, rest LVEF 55% +/- 14% vs 59% +/- 12%, stress EDV/ESV 144 ml/71 ml vs 128 ml/59 ml, P < 0.05), and CAC score (1 965 +/- 1 772 vs 387 +/- 740, P < 0.05) in comparison with patients without cardiac event. In patients without a reversible perfusion abnormality (SDS < 2), we observed lower annual hard event rate (8% vs 19.6%, P < 0.05) and revascularization procedures (4% vs 19.6%, P < 0.05) in comparison with patients with SDS > or = 2. In patients with or without reversible defects, we registered significantly higher annual hard event rate in the setting of post-stress worsening of the LVEF > 5% and/or severe CAC score > or = 709 (23.8% vs 1.9% in patients with SDS < 2, and 26.7% vs 9.5% in patients with SDS > or = 2, P < 0.05). CONCLUSION: The findings of highly elevated CAC score as well as the post-stress left ventricle stunning enable further risk stratification in patients with or without reversible perfusion abnormalities.

[Myocardial viability findings interpretation using SPECT and PET imaging]. / Zobrazovací metody v diagnostice viability myokardu. Cást 1. Interpretace nálezu pri zobrazování viability myokardu pomocí SPECT a PET.

Myocardial perfusion and function imaging using single photon emission computed tomography (SPECT) plays the important role in coronary artery disease diagnostics and risk stratification, however, there is nowadays growing significance of the myocardial viability detection. A glucose metabolism assessment using positron emission tomography (PET) becomes accessible also. A brief review is given about the interpretation principle in the viable myocardium diagnosis and current progress in perfusion and metabolism defect severity quantification in patients with the left ventricular dysfunction.

[The importance of determining the viability of the myocardium prior to revascularisation in patients with ischaemic cardiomyopathy and left ventricular systolic dysfunction]. / Význam stanovení viability myokardu pred revaskularizací u pacientu s ischemickou kardiomyopatií a systolickou dysfunkcí levé komory srdecní.

Chronic heart failure is a worldwide clinical syndrome with substantial socio-economical impact. The aim of this overview is the summary of contemporary knowledge in epidemiology, elementary pathophysiological implications and some possibilities of treatment of ischemic cardiomyopathy, which represents the most frequent cause of heart failure in developed countries. Emphasis is on the right indication for myocardial revascularization as a causal option of therapy of ischemic cardiomyopathy, timing and risk of revascularization and especially on importance of assessment of viability of myocardium using presently available imaging methods.

Purification and determination of plant hormones auxin and abscisic acid using solid phase extraction and two-dimensional high performance liquid chromatography.

A method for separation and purification of plant hormones auxin and abscisic acid based on mixed mode reversed-phase anion-exchange solid phase extraction and two-dimensional HPLC was developed. Two-dimensional HPLC in "heart cutting" mode was very efficient in the purification of these two hormones. Its purification power is high enough to allow reliable on-line quantification of both hormones even with non-selective detectors.

[Validity of bone scintigraphy for the diagnosis of periprosthetic complications in hydroxyapatite-coated total hip arthroplasty]. / Prínos trífázové kostní scintigrafie k diagnostice periprotetických komplikací u protézy s hydroxyapatitovým povrchem.

PURPOSE OF THE STUDY: To evaluate the efficacy and usefulness of 99Tc-MDP bone scans for the diagnosis of complications associated with hydroxyapatite- coated total hip prostheses. MATERIAL AND METHODS: 99Tc-MDP bone scans of 42 hips were taken before revision surgery in 41 patients with ABG 1 prostheses. Of these, 26 patients (27 hips) were included in our study on the basis of the following criteria: at least 23 months between the index surgery and scintigraphic examination and the availability of good quality bone scans. The average patients' age at the time of index and revision operations was 45.3 years (range, 32-57; SD, 6.02) and 50.2 years (36-61; SD, 6.01), respectively. The average time between the index surgery and bone scintigraphy was 50.3 months (23-84; SD, 15.9). Two experienced specialists in nuclear medicine, who were unaware of any clinical conclusions, participated in the study. RESULTS: Pre- and intra-operative findings showed aseptic loosening in three cups (3/27, 11 %) and one stem (1/27, 4 %). Four hips were suspected to have an infection on the basis of the positive results of intra-operative culture. In the diagnosis of aseptic loosening, sensitivity, specificity, accuracy, and positive and negative predictive values of bone scintigraphy were 100 %, 57 %, 62 %, 23 %, and 100 %, respectively, for the ABG I cup and 100 %, 52 %, 54 %, 8 %, and 100 %, respectively, for the ABG I stem. These characteristics were 67 %, 96 %, 93 %, 67 %, and 96 %, respectively, for the ABG I cup, when plain X-ray was used for evaluation of aseptic loosening. Specificity, accuracy and negative predictive value of plain X-ray for ABG I stem aseptic loosening were 100 %, 96 %, and 96 %. Bone scintigraphy gave one false positive result of sepsis; on the other hand, none of the four hips with positive intraoperative culture was diagnosed as septic. DISCUSSION: The fact that 99Tc-MDP bone scintigraphy as a method of diagnosing periprosthetic complications has a high sensitivity and a relatively low specificity has often been discussed in the literature. Currently, there are only a few studies on bone scintigraphy investigations of hydroxyapatite-coated prostheses. Some authors report that a slight increase in peri-prosthetic radionuclide activity may persist for up to 8 years which can explain the problematic accuracy of the technique. CONCLUSIONS: 99Tc-MDP bone scintigraphy is an intermediate useful tool for detecting complications of total hip arthroplasty with hydroxyapatite- coating. A negative bone scan almost always suggested the absence of aseptic loosening. However, the value of a positive result was regarded as controversial for the diagnosis of both aseptic and septic complications.

The accuracy of myocardial perfusion SPECT imaging in the evaluation of coronary artery disease in women and men.

BACKGROUND: The purpose of this study is to compare sensitivity, specificity and accuracy of myocardial perfusion SPECT for the detection of coronary artery disease (CAD) in women and men. MATERIAL AND METHODS: 588 patients (455 males and 133 females, 273 after a previous myocardial infarction) underwent stress myocardial perfusion SPECT. The accuracy of myocardial perfusion SPECT was proved by coronary angiography (stenosis > 50% was considered as a CAD). RESULTS: The sensitivity of SPECT was slightly higher, but statistically not significant, in men than in women (94% versus 91%, p > 0.05). The specificity was higher in women than in men (93% versus 82%), but this difference was not statistically significant either (p > 0.05). The accuracy of SPECT was the same for both sexes (92%). In angiographically verified group of patients the selection bias was obvious--patients with CAD dominated (74%) and the fraction of patients with CAD in men's group (83%) was significantly higher than in women's group (50%), p < 0.05. CONCLUSIONS: No significant difference was revealed in the accuracy of myocardial perfusion SPECT in men and women. Our results are in accordance with the prevailing opinion in literature that discovered differences in sensitivity, specificity and diagnostic accuracy are usually not statistically significant or that they can be explained by the selection bias of patients in angiographically verified groups (significantly higher fraction of patients with CAD in men's group).

[Prognostic significance of stress tomographic scintigraphy of myocardial perfusion in diabetic patients]. / Prognostický význam zátezové tomografické scintigrafie myokardiální perfuze u diabetických pacientu.

OBJECTIVE: To assess the prognostic value of SPECT in patients with diabetes (DM) and without DM. METHOD: A total of 366 patients (104 women, 262 men) were examined by T1 +/- 201 or Tc-99m-MIBI SPECT of the myocardium. DM was recorded in 149 patients, 217 patients did not suffer from DM. The SPECT findings were classified as normal and abnormal perfusion (fixed or reversible perfusion defect). A serious cardiac event was defined as sudden cardiac death or non-fatal myocardial infarction. Also angina pectoris requiring revascularization was recorded. RESULTS: During the average investigation period of 24 +/- 7 months we recorded in 147 patients with a normal load perfusion only one non-fatal myocardial infarction and the risk of a serious cardiac event was low: 0.3% per annum in the whole group. A significantly higher incidence of a severe cardiac event, 5.9% per year, was recorded in 219 patients with an abnormal finding on SPECT (10 deaths and 16 non-fatal myocardial infarctions, P < 0.01). On comparison of the frequency of serious cardiac events in groups of patients with and without DM no significant difference was found as regards normal load perfusion of the heart muscle (1.1% vs. 0%, P = NS) even in patients with an abnormal SPECT finding (5.8% vs. 6.1, P = NS). CONCLUSION: SPECT myocardial perfusion makes it possible to stratify the risk in patients with DM similarly as proved previously in non-selected groups. Similarly as in patients without DM normal perfusion in diabetic patients predicts a benign prognosis.

Prognostic value of myocardial perfusion tomographic imaging in patients after percutaneous transluminal coronary angioplasty.

PURPOSE: The authors assessed the prognostic value of stress myocardial perfusion tomographic imaging (SPECT) in patients with recurrent angina or inconclusive results of exercise electrocardiographic tests after successful percutaneous transluminal coronary angioplasty (PTCA). MATERIALS AND METHODS: After PTCA, 70 patients (54 men, 16 women; 41 after myocardial infarction; mean age, 56 +/- 9 years) underwent TI-201 or Tc-99m sestamibi SPECT studies. SPECT patterns were divided into normal (n = 25), fixed defects (n = 15), and reversible or combined fixed plus reversible defects (n = 30). A cardiac event was defined as either cardiac death, nonfatal myocardial infarction, or unstable angina requiring further revascularization. RESULTS: During an average follow-up of 25 +/- 10 months, two patients had severe outcomes (one cardiac death and one nonfatal myocardial infarction), and revascularization was required in 13 patients. In patients with normal SPECT or fixed defects, the annual event rate was low (1.2%), with only one revascularization. In patients with reversible or combined defects, the annual event rate was significantly greater (22.4%; chi square = 17.32, P = 0.00003). CONCLUSIONS: Normal perfusion or fixed defects predict a benign prognosis in patients after successful PTCA. The presence of stress-induced reversible defects appears to be the best predictor of future cardiac events.

[Myocardial perfusion tomography imaging in patients without prior myocardial infarction--comparison between 201Tl, 99mTc-tetrofosmin and dual-isotope protocol (rest 201Tl/stress 99mTc-tetrofosmin)]. / Tomografické zobrazení myokardiální perfuze u pacientu bez infarktu myokardu--srovnání 201Tl s 99mTc-tetrofosminem a dual-izotopovým protokolem (klid 201Tl/zátez 99mTc-tetrofosmin).

The authors compared retrospectively the diagnostic accuracy of three protocols--201Tl stress-redistribution, 2-day 99mTc-tetrofosmin and the dual-isotope protocol (rest 201Tl/stress99m Tc-tetrofosmin)--for the detection of ischaemic heart disease (IHD) in a total of 115 patients without previous myocardial infarction (IM). 201Tl protocol (group A) was used to examine 43 patients, incl. 15 women, mean age 51 years (38-69 years). The 2-day 99m Tc-tetrofosmin protocol was used to examine 39 patients incl. 12 women, mean age 49 years (30-71 years). The dual-isotope protocol was used in 33 patients, incl. 8 women, mean age 52 years (31-69 years). In all patients coronarography was performed, stenosis of the artery >50% was considered significant for IHD. The sensitivity of the dual-isotope protocol was 95% and 96% resp. and 92% in the 2-day tetrofosmin and 201Tl protocol, (p>0.05). The specificity of the dual-isotope protocol was 82% and 89% resp. and 88% in the 201Tl and 2-day tetrofosmin protocol, (p >0.05). The diagnostic accuracy was 91% in the dualisotope and 201Tl protocol and 92% in the 2-day protocol (p>0.05). No significant difference was revealed in the sensitivity, specificity and diagnostic accuracy for the detection of IHD between different protocols in patients without previous IM.

[Correlation of SPECT myocardial stress scintigraphy with coronary angiography]. / Korelace zátezové perfuzní scintigrafie myokardu SPECT s koronarografickými nálezy.

The sensitivity and specificity of a myocardial perfusion single-photon emission tomography (SPECT) for the detection of the coronary artery disease (CAD) was investigated. As a gold standard the coronary angiography was used--the stenosis of the artery by 50% and more was considered as significant for CAD. After performing SPECT studies patients were examined by coronary angiography according to the attending physician's judgement. In the retrospectively created group of 123 subjects (94 males and 29 females, mean age 53 years, range 30-69 years) 55 patients underwent myocardial infarction (MI). The stress was performed using a bicycle ergometer or, in case of patient's inability, an intravenous dipyridamole infusion. Before december 1995 201T1 was used in all patients, after this date only in patients with prior MI with regard to the advantage of this radionuclide for the detection of the ischemic but viable myocardium. Other patients were administered 99mTc-tetrofosmin. In our group of patients we found the high sensitivity of myocardial SPECT of 94.5% 86 (from 91), specificity of 84.4% (27 from 32) corresponding to usually values and the high diagnostic accuracy of 91.9% (113 from 123). Specificity can be impaired by marked attentuation of gamma-rays by overlying soft-tissue structures such as the breast or diaphragm. The artificial imaging of the inferior wall due to the infradiaphragmatic structures represents the most serious problem-there were four false positive findings in our group; further ones in our 99mTc-tetrofosmin studies were avoided by the routine use of the prone position recommended in the literature. The validity of SPECT myocardial perfusion findings should be verified by coronary angiography; however, one must be aware of some questionable points inherent in this comparison.

Changes in Cytokinin Content and Cytokinin Oxidase Activity in Response to Derepression of ipt Gene Transcription in Transgenic Tobacco Calli and Plants.

Metabolic control of cytokinin oxidase by its substrate was investigated in planta using wild-type (WT) and conditionally ipt gene-expressing transgenic (IPT) tobacco (Nicotiana tabacum L.) callus cultures and plants. The derepression of the tetracycline (Tc)-dependent ipt gene transcription was followed by a progressive, more than 100-fold increase in total cytokinin content in IPT calli. The activity of cytokinin oxidase extracted from these calli began to increase 16 to 20 h after gene derepression, and after 13 d it was 10-fold higher than from Tc-treated WT calli. An increase in cytokinin oxidase activity, as a consequence of elevated cytokinin levels, was found in detached leaves (8-fold after 4 d) and in roots of intact plants (4-fold after 3 d). The partially purified cytokinin oxidase from WT, repressed IPT, and Tc-derepressed IPT tobacco calli exhibited similar characteristics. It had the same broad pH optimum (pH 6.5-8.5), its activity in vitro was enhanced 4-fold in the presence of copper-imidazole, and the apparent Km(N6-[[delta]2iso-pentenyl]adenine) values were in the range of 3.1 to 4.9 [mu]M. The increase in cytokinin oxidase activity in cytokinin-overproducing tissue was associated with the accumulation of a glycosylated form of the enzyme. The present data indicate the substrate induction of cytokinin oxidase activity in different tobacco tissues, which may contribute to hormone homeostasis.