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T Katila

Publications and source records attributed to T Katila.

At least 19 recordsLinked to original sources
PubMed2002

Short estrous cycles and estrous signs after premature ovulations induced with cloprostenol and gonadotropin-releasing hormone in cyclic dairy cows.

The aim of the present study was to confirm earlier findings, obtained with a small number of animals, that gonadotropin-releasing hormone (GnRH) can shorten corpus luteum functional life when it is administered 24 h after cloprostenol (PG) treatments given 7-9 days after estrus. In addition, the effects of two treatments, PG alone or PG + GnRH given before mid-diestrus, on signs of estrus were studied. Sixty cows in farm conditions were used in the experiment. Eight days after natural estrus, they were given an intramuscularly (i.m.) treatment of cloprostenol (0.5 mg). The animals were then divided into two groups. One group (n = 25) received an i.m. treatment of gonadorelin (0.1 mg) 24 h after the PG treatment (PG + GnRH group), while another group (n = 35) served as controls without any further treatment (PG group). Estrous signs were recorded. Progesterone concentrations were measured from samples of whole milk. No short cycles were observed in the PG group, whereas 33% of the cows in the PG + GnRH group exhibited premature luteal regression (P < 0.05). Cloprostenol treatment on Day 8 had no effect on the intensity of the estrous signs. Instead, GnRH treatment 24 h after PG treatment weakened the estrous signs significantly (P < 0.01). It is concluded that GnRH administration 24 h after a PG treatment given 8 days after estrus can cause short estrous cycles in some cows on an individual basis.

Animals↗
PubMed2002

Heart rate adjustment of magnetic field map rotation in detection of myocardial ischemia in exercise magnetocardiography.

AIMS: We studied the capability of heart rate (HR) adjusted change in multichannel magnetocardiogram (MCG) to detect exercise-induced ischemia. METHODS AND RESULTS: The MCG and 12-lead ECG were recorded simultaneously during supine exercise testing in 17 healthy controls and 24 patients with single vessel coronary artery disease (CAD). In the MCG analysis, we plotted the orientation of the magnetic field map (MFM) against the HR in each cardiac cycle during recovery. A regression line was fitted to the data and the line slope (degrees/bpm) was determined. In the ECG, the ST-segment depression vs HR (ST/HR) slope was evaluated. The HR adjusted MFM rotation was more extensive in the pooled CAD group, and in all subgroups with different stenosed vessel, than in the control group at the ST-segment (1.5 +/- 2.1 degrees/bpm vs 0.29 +/- 0.25 degrees/bpm, p < 0.0005) and at the T-wave apex (0.95 +/- 0.81 degrees/bpm vs 0.24 +/- 0.25 degrees/bpm, p < 0.0005). Areas under the receiver operating characteristic curves of the HR adjusted MFM rotation at the ST-segment (88.5%) and the T-wave (86.0%) were higher than the ones without HR adjustment (75.5% and 68.1%, respectively), and higher than the area of ST/HR slope in the ECG (80.2%). CONCLUSION: HR adjusted MFM rotation detects transient ischemia independent of the stenosed vessel. HR adjustment improves the performance of the MCG in ischemia detection by the analysis of the ST-segment and the T-wave. The MCG was superior to the 12-lead ECG.

Aged↗
PubMed2002

Proteins and enzymes in uterine lavage fluid of postpartum and nonparturient mares.

Uterine lavage fluids from postpartum and nonparturient mares were compared to determine when the normal secretory capacity of the postpartum uterus is restored. Lavage fluids were obtained from cyclic nonparturient mares on the second, fourth or fifth day of oestrus, and 3, 8, or 14 days after ovulation (seven mares/sampling day). Twelve intact postpartum mares were sampled 1 to 28 days postpartum (group A: 1, 6, 12 and 20; group B: 2, 8, 14 and 24; group C: 4, 10, 16 and 28 days postpartum; four mares/group). Three ovariectomized (OVX) postpartum mares were sampled as mares in group C. Samples were analysed for neutrophils, bacteria, total protein concentration, proteolytic and antiproteolytic activities and for various lysosomal enzyme activities. In nonparturient mares, activities of acid phosphatase, beta-glucuronidase (B-Gase), and N-acetyl-beta-D-glucosaminidase (NAGase) in uterine lavage fluids were significantly higher in mid- and late-dioestrus than in mid- to late-oestrus (p < 0.05). Lysozyme concentration, trypsin-inhibitor capacity (TIC), and plasmin activity were below the detection limit in nonparturient mares. One to four days postpartum, total protein, acid phosphatase, B-Gase, and NAGase were high but declined rapidly thereafter. Lysozyme and plasmin activities were high 1 to 6 days postpartum. TIC peaked around day 6 postpartum. On day 16 postpartum, acid phosphatase, B-Gase, and NAGase, being progesterone-dependent, tended to be higher in intact mares than in OVX ones (p < 0.1). Total protein and lysozyme concentrations, TIC, and B-Gase (p < 0.01) and acid phosphatase (p < 0.05) activities were significantly higher in parturient mares during postpartum oestrus than in oestrous nonparturient mares. High total protein concentration and TIC, and detectable lysozyme and plasmin activities during postpartum oestrus were associated with uterine inflammation. During dioestrus, differences between postpartum and nonparturient mares were not statistically significant and suggested that the endometrium of postpartum mares had resumed its normal secretory capacity by this time.

Acetylglucosaminidase↗
PubMed2001

Sperm-uterine interactions: a review.

The uterus of domestic animals, including the horse, has a dual role in the interaction of the uterus and sperm. On one hand, uterine contractions carry sperm toward the oviduct, and on the other hand the uterus eliminates excessive sperm. The selection of sperm for the small numbers of "good" cells that gain access to the oviduct and for the majority of sperm that will be destroyed takes place in the uterus. The sperm-uterine interaction works both ways; sperm and seminal plasma also have several effects on the uterus. Sperm and seminal plasma probably provoke uterine contractions. Sperm induce leukocytosis in the equine uterus by activating complement. Seminal plasma has immuno-suppressive effects in the uterus. The sperm-uterine interaction can be modified by the type of the inseminate: concentration, numbers, motility/viability of sperm, volume, and absence or presence of seminal plasma. In mares, relaxation of the cervix, myometrial contractions, lymphatic drainage, and stallion contact affect elimination of sperm.

Animals↗
PubMed2001

ST-segment level and slope in exercise-induced myocardial ischemia evaluated with body surface potential mapping.

Body surface potential mapping (BSPM) is superior to 12-lead electrocardiography for detection of acute and old myocardial infarctions (MIs). We used BSPM to examine electrocardiographic criteria for acute reversible myocardial ischemia. BSPM with 123 channels was performed in 45 patients with coronary artery disease (CAD) and 25 healthy controls during supine bicycle exercise testing. Of the 45 patients, 18 patients had anterior, 14 had posterior, and 13 had inferior ischemia documented by coronary angiography and thallium scintigraphy. The ST amplitude was measured 60 ms after the J-point and the ST slope calculated by fitting a regression line from the J-point to 60 ms after it. The optimal locations for detecting ST depression and ST-slope decrease were identified. In the pooled CAD patient group, the optimal location for ST depression was 5 cm below standard lead V(5) (CAD group: -70 +/- 70 microV; controls: 70 +/- 80 microV, p <0.001). Using a cut-off value of -10 microV, the ST depression separated the patients with CAD from controls with a sensitivity of 84% and a specificity of 96%. The ST slope became more horizontal in the patient group than in the control group. The optimal location for ST-slope decrease was over the left side (CAD group: 20 +/- 20 microV/s; controls: 720 +/- 320 microV/s, p <0.001). Using a cut-off value of 320 microV/s, the ST slope separated patients with CAD from controls with a sensitivity of 93% at a specificity level of 88%. The area under the receiver operating characteristic curve of ST slope tended to be higher than the one of ST depression (97% vs 93%; p = 0.097). In conclusion, regions sensitive for ST depression and for ST-slope decrease could be identified in BSPM, despite variation in the location of ischemia and the presence or absence of a history of MI. ST slope is a sensitive and specific marker of transient myocardial ischemia, and might perform even better than ST depression.

Body Surface Potential Mapping↗
PubMed2001

Reproducibility of fMRI: effect of the use of contextual information.

We studied the effect of use of contextual information on the reproducibility of the results in analysis of fMRI data. We used data from a repeated simple motor fMRI experiment. In the first approach, statistical parametric maps were computed from a spatially unsmoothed data and thresholded using a Bonferroni corrected threshold. In the second approach, the maps were computed from a spatially unsmoothed data but were segmented into nonactive and active regions using a spatial contextual clustering method. In the third approach, the statistical parametric maps were computed from spatially smoothed data and thresholded, using, optionally, a spatial extent threshold. The variation in the classification was largest in the Bonferroni thresholded statistical parametric maps. There were no significant differences in variation between statistical parametric maps generated with all the other methods. In addition to reproducibility, the detection rates of weak simulated activations in the presence of measured scanner and physiological noise were investigated. Contextual clustering method was the most sensitive method, while the least sensitive method was the Bonferroni corrected thresholding. Using simulated data, we demonstrated that the contextual clustering method preserves the shapes of activation regions better than the method using spatial smoothing of the data.

Adult↗
PubMed2001

Recording locations in multichannel magnetocardiography and body surface potential mapping sensitive for regional exercise-induced myocardial ischemia.

INTRODUCTION: This study aimed to identify the optimal locations in multichannel magnetocardiography (MCG) and body surface potential mapping (BSPM) to detect exercise-induced myocardial ischemia. METHODS: We studied 17 healthy controls and 24 coronary artery disease (CAD) patients with stenosis in one of the main coronary artery branches: left anterior descending (LAD) in 11 patients, right (RCA) in 7 patients, and left circumflex (LCX) in 6 patients. MCG and BSPM signals were recorded during a supine bicycle stress test. The capability of a recording location to separate the groups was quantified by subtracting the mean signal amplitude of the normal group from that of the patient group during the ST segment and at the T-wave apex, and dividing the resulting amplitude difference by the corresponding standard deviation within all subjects. RESULTS: In MCG the optimal location for ST depression was at the right inferior grid for the RCA, at the mid-inferior grid for the LCX, and in the middle of these locations for the LAD subgroup (mean ST amplitudes: CAD -80 +/- 360fT, controls 610 +/- 660fT; p < 0.001). In BSPM it was on the left upper anterior thorax for the LAD, left lower anterior thorax for the RCA, and on the lower back for the LCX subgroup (mean ST amplitudes: CAD -39 +/- 61 microV and controls 38 +/- 38 microV; p < 0.001). In MCG the optimal site for T-wave amplitude decrease was the same as the one for the ST depression. In BSPM it was on the middle front for the LAD, on the back for the LCX and on the left abdominal area for the RCA group. In accordance with electromagnetic theory, the largest ST segment and T-wave amplitude changes took place in MCG in locations orthogonal to those in BSPM. CONCLUSION: This study identified magnetocardiographic and BSPM recording locations which are sensitive for detecting transient myocardial ischemia by evaluation of the ST segment as well as the T-wave. These locations strongly depend on ischemic regions and are outside the conventional 12-lead ECG recording sites.

Aged↗
PubMed2001

WWW--an effective way of teaching radiology.

The Internet and especially the World Wide Web (WWW) have given new opportunities and challenges in teaching radiology. In Kuopio University and Kuopio University Hospital, we started to develop a new WWW-based radiology teaching file in 1996. Our file was made as a result of weaknesses in other files and as an answer to our local needs. The file consists of 1245 separate radiographs in 14 different categories. The language is Finnish, because the target use primarily is basic medical education in Finland. A small part has been translated into English. The quality of images was improved using a separate viewer (Osiris, Digital Imaging Unit, University Hospital of Geneva, Switzerland), which also allowed image manipulation needed with radiological images. We have monitored the utilisation of pages (Analog 1.92 beta-3.0/UNIX) and found the results encouraging. The follow-up time was 814 days (10 February 1997-27 September 1999), the total number of requests was 762797 and that for HTML pages is 288664. Monthly means are 27243 and 10309, respectively. The total number for visited domains is 61. The URL for these pages is http://www.uku.fi/laitokset/klrad/opetuskuvasto/.

Humans↗
PubMed2001

Magnetocardiographic intra-QRS fragmentation analysis in the identification of patients with sustained ventricular tachycardia after myocardial infarction.

The aim of this study was to investigate if magnetocardiographic (MCG) analysis of cardiac micropotentials within the QRS complex can identity patients prone to ventricular arrhythmias, and to compare it to MCG time-domain, late-field analysis. The study population consisted of 136 patients with remote MI, 53 with and 83 without a history of VT. After averaging and high pass filtering of multichannel MCG signals, time-domain parameters describing the end-QRS activity and fragmentation index M and score S describing the whole QRS complex were computed. Fragmentation and time-domain parameters differed between the VT and control groups: fragmentation index M was 12 +/- 3 versus 9 +/- 2 (P <0.001), fragmentation score S was 83 +/- 42 versus 56 +/- 21 (P < 0.001), and filtered QRS duration was 144 +/- 32 versus 114 +/- 19 ms (P < 0.001) in VT and control groups, respectively. A combination of fragmentation parameters yielded 87% sensitivity and 61% specificity in VT identification. Corresponding figures for a time-domain parameter combination were 81% and 72%. Sensitivity of time-domain analysis was 88% and specificity was 75% in a subgroup with anterior MI. In multivariate analysis, fragmentation and time-domain analyses discriminated VT patients from controls independently of the extent of coronary artery disease or left ventricular dysfunction. MCG in postinfarction patients reveals pathology associated with propensity to ventricular arrhythmias inside and not only at the end of the QRS complex. MCG seems most accurate in the anterior infarct location.

Aged↗
PubMed2001

Repolarization abnormalities detected by magnetocardiography in patients with dilated cardiomyopathy and ventricular arrhythmias.

INTRODUCTION: Abnormal repolarization is one of the acknowledged mechanisms leading to malignant ventricular arrhythmias. We used a novel magnetocardiographic technique to investigate the role of inhomogeneous repolarization in patients with nonischemic dilated cardiomyopathy prone to sustained ventricular arrhythmias. METHODS AND RESULTS: Forty-nine dilated cardiomyopathy patients were studied, 18 with a history of sustained ventricular tachycardia (n = 6) or ventricular fibrillation (n = 12) and 31 with no ventricular arrhythmias. The magnetocardiogram was registered and QT apex and QT end intervals were determined by a computer algorithm. Inhomogeneity of repolarization was characterized with indices describing QT apex and QT end dispersion, and T wave end duration. In addition, time-domain late fields of the QRS complex in magnetocardiography and QT dispersion in 12-lead ECG were determined. T wave end was longer in the arrhythmia group in patients with sinus rhythm (87 +/- 15 msec vs 73 +/- 12 msec; P = 0.005) and in those not having bundle branch block. Magnetocardiographic late fields of the QRS complex were not different between groups. QT apex and end dispersion on magnetocardiography or 12-lead ECG showed no difference. CONCLUSION: Prolongation of the end part of the T wave revealed by magnetocardiography is related to malignant ventricular arrhythmias in dilated cardiomyopathy. The results suggest that abnormal repolarization rather than delayed conduction underlies the arrhythmias in this disease.

Adult↗
PubMed2001

Postmyocardial infarction patients susceptible to ventricular tachycardia show increased T wave dispersion independent of delayed ventricular conduction.

INTRODUCTION: Experimentally, both delayed ventricular conduction and nonhomogeneous ventricular repolarization contribute to reentrant arrhythmias. We tested the hypothesis that increased T wave dispersion is independent of delayed ventricular conduction associated with arrhythmia vulnerability in postmyocardial infarction (post-MI) patients. METHODS AND RESULTS: We studied 32 post-MI patients with clinical or inducible monomorphic ventricular tachycardia (VT group), 28 post-MI patients without arrhythmias (MI group), and 13 healthy controls, using magnetocardiographic (MCG) mapping with signal averaging. Twelve-lead ECG was the reference. Filtered QRS duration (fQRS) and T wave peak to T wave end interval (TPE) were used as measures of ventricular conduction and nonhomogeneity in ventricular repolarization, respectively. In MCG, the VT group showed the longest fQRS (135+/-34 msec vs 114+/-22 msec in the MI group; P = 0.012). Mean TPE and maximum TPE in VT versus MI groups were 78+/-9 msec versus 70+/-6 msec (P < 0.001) and 117+/-23 msec versus 104+/-19 msec (P = 0.020), respectively. Maximum TPE did not correlate with fQRS in the VT group (r = 0.063; P = NS) but did correlate in the MI group (r = 0.396; P = 0.037). For identification of post-MI patients prone to VT, selection of cutoff values for fQRS >140 msec and mean TPE >81 msec gave sensitivity and specificity of 41% and 89%, and 31% and 96%, respectively. Their combination increased sensitivity to 63% while maintaining 89% specificity. CONCLUSION: Post-MI patients susceptible to VT show increased T wave dispersion independent of delayed ventricular conduction.

Aged↗
PubMed2001

Current-density estimation of exercise-induced ischemia in patients with multivessel coronary artery disease.

Magnetocardiographic and body surface potential mapping data measured in 6 patients with multivessel coronary artery disease were used in equivalent current-density estimation (CDE). Patient-specific boundary-element torso models were acquired from magnetic resonance images. Positron emission tomography data registrated with anatomical magnetic resonance imaging data provided the gold standard. Discrete current-density estimation values were computed on the epicardial surface of the left ventricle from difference (stress-rest) ST-segment maps. The ill-posed inverse problem was regularized with 3 different methods (Tikhonov regularization with an identity or a surface Laplacian operator and a maximum a posteriori estimator). Comparisons with positron emission tomography studies showed that the maximum a posteriori estimator is superior to other regularizations, provided that a suitable a priori information is available. In general, good correspondence was found for segments of high and low amplitude in current-density estimations, and the viable and scar areas in positron emission tomography, respectively.

Body Surface Potential Mapping↗
PubMed2001

Beat-to-beat analysis method for magnetocardiographic recordings during interventions.

Multichannel magnetocardiography (MCG) during exercise testing has been shown to detect myocardial ischaemia in patients with coronary artery disease. Previous studies on exercise MCG have focused on one or few time intervals during the recovery period and only a fragment of the data available has been utilized. We present a method for beat-to-beat analysis and parametrization of the MCG signal. The method can be used for studying and quantifying the changes induced in the MCG by interventions. We test the method with data recorded in bicycle exercise testing in healthy volunteers and patients with coronary artery disease. Information in all cardiac cycles recorded during the recovery period of exercise MCG testing is, for the first time, utilized in the signal analysis. Exercise-induced myocardial ischaemia was detected by heart rate adjustment of change in magnetic field map orientation. In addition to the ST segment, the T wave in the MCG was also found to provide information related to myocardial ischaemia. The method of analysis efficiently utilizes the spatial and temporal properties of multichannel MCG mapping, providing a new tool for detecting and quantifying fast phenomena during interventional MCG studies. The method can also be applied to an on-line analysis of MCG data.

Coronary Disease↗
PubMed2001

In vitro evaluation of frozen-thawed stallion semen: a review.

The article reviews methods used for in vitro evaluation of sperm, with particular emphasis on frozen-thawed stallion sperm. The techniques, limitations of the methods and correlations with fertility results are discussed. Very few studies have tried to find correlation between fertility of frozen stallion semen and laboratory tests. It is difficult and expensive to inseminate an adequate number of mares to achieve statistically significant differences. Significant, but low correlations have been demonstrated between the foaling rate and subjective motility of sperm incubated for 2 h and 4 h at 37 degrees C and hypoosmotic swelling test after 0 and 3 h of incubation. Significant correlations have been reported between the pregnancy rate and viability of propidium iodide-stained sperm assessed by flow cytometry as well as for glass wool and Sephadex filtration tests. No correlations have been detected between fertility and motility immediately after thawing. In spite of that, motility estimation by light microscope is the most commonly used method to evaluate frozen-thawed stallion sperm. Computer assisted automatic sperm analyzers have replaced light microscopy in research projects, but so far nobody has been able to demonstrate a correlation between fertility of frozen stallion semen and any of the motility parameters obtained by these instruments.

Animals↗
PubMed2000

Administration of gonadotropin-releasing hormone during metoestrus in cattle: influence on luteal function and cycle length.

Gonadotropin-releasing hormone (GnRH) has been used to warrant the success of artificial insemination by accurately timing occurrence of ovulation. In practical conditions, GnRH may be administered too late, after ovulation, with an eventual reduction in pregnancy rate. The aim of this study was to investigate whether GnRH administration after ovulation would have a negative effect on luteal function. Three cows and six heifers of the Finnish Ayrshire breed were used. Oestruses were synchronised. After detection of ovulation, one of the following treatments was implemented: gonadorelin (250 microg, i.m.) at either 0-24h (T1) or 24-48h (T2) post-ovulation or control (no gonadorelin, C). Every animal was assigned once to each of these three manipulations. Ultrasonography was performed on days 1, 4 or 5, 7 or 8, 11 or 12, 14 or 15 post-ovulation and daily from the beginning of the next oestrous signs until ovulation (day 0=day of ovulation). Blood samples for progesterone (P(4)) determinations were collected daily from day 1 after the occurrence of ovulation until recording of the next oestrus. Administration of GnRH during metoestrus did not induce ovulation of either large or small follicles and, thus, no accessory corpora lutea (CL) were formed. In T1, on day 14 or 15, the diameter of CL was 1.3+/-0.3mm smaller than in C (P<0.01), but no differences were found either on days 11 or 12 or on the same days of the T2 and C treatments. No significant differences in levels or profiles of P(4) curves were found between GnRH treatments and control. Neither had the treatments any effects on the length of the oestrous cycle. In conclusion, GnRH treatment during metoestrus does not seem to alter subsequent luteal function and, thus, this does not explain previous reports of reduced fertility post-treatment.

Animals↗
PubMed2000

T-cell distribution in two different segments of the equine endometrium 6 and 48 hours after insemination.

The T-cell response after the introduction of semen into the uterine cavity in the mare was studied by examining, immunohistochemically, the distribution of helper T-cells (CD4+) and cytotoxic T-cells (CD8+) in endometrial biopsy specimens. Endometrial tissue samples were obtained from twenty-five gynecologically healthy mares during estrus before and 6 or 48 h after deposition of a single dose of stallion semen. An increase (P=0.04) in the number of helper T-cells (CD4+) compared to pre-insemination values was observed in the uterine body in both groups, 6 and 48 h, after insemination. No significant variations in numbers of CD8+ cells were recorded either 6 or 48 h after insemination. There seems to be an early (6 h) recruitment of helper T-cells to the equine endometrium after semen deposition, which might be related to the activation of the endometritis-like reaction seen as part of the equine uterine immune defense during estrus.

Animals↗