P1963The determinants of functional significance of coronary bifurcation lesions and its implications on clinical follow up to 48 months (insights from FIESTA registry)

Background

There is no study up-to-now to determine the rate of functionally significant coronary bifurcation lesions, which have to be intervened and what are the clinical consequences of the FFR case selection strategy.

Methods

We analyzed patients from FIESTA registry, which was continuation of FIESTA study (Ffr vs. IcEcgSTA, ClinicalTrials.gov Identifier: NCT01724957). Patients with stable angina were included (if there were other coronary stenoses they were threated first after checking by FFR for functional significance). The inclusion criterions were angiographic bifurcation lesions in a native coronary artery with diameter ≥2.5 mm and ≤4.5 mm and SB diameter ≥2.0 mm. We excluded patients with ST-segment elevation myocardial infarction, left main, hemodynamic instability and those with non-cardiac co-morbidity conditions with a life expectancy of less than one year. PCI was performed according to the current guidelines. Provisional stenting was the default strategy in all patients. Two guidewires were inserted into both distal MB and SB. Initial FFR was performed using the PrimeWire or PrimeWire Prestige (Volcano Corp., USA). For all FFR measurements, intracoronary adenosine was given in increasing doses of 60 mcg, 120 mcg, and 240 mcg. The minimum value of FFR measurements was taken for analysis. All patients received double antiplatelet therapy with ADP-antagonist and aspirin for at least 12 months.

Results

A 130 consecutive patients with coronary bifurcation stenoses were included – 57 had positive FFR<.80 in main vessel of bifurcation lesion (44% functionally significant lesions). The mean age was 67±10 years, 66% males, 96% hypertensive, 39% diabetic, 96% dyslipidemic (or on treatment with statin), 55% smokers, 22% with previous myocardial infarction, 51% with previous PCI. The residual SYNTAX score before FFR bifurcation assessment was 13±4 (FFR<.80) vs. 8±3 (FFR≥0.80), p<0.001. Univariate predictors of bifurcation FFR<.80 were: proximal (MV%DS) or distal (MB%DS) main vessel stenosis ≥85% (derived from ROC analysis with overall accuracy 77% and 72%, accordingly), lesion length, SYNTAX score, triglyceride concentration, previous MI on lateral wall and carotid artery disease. On multivariate logistic analysis only MV%DS>85% (OR=8.929, CI 2.887–27.619, p<0.001), MB%DS>85% (OR=3.831, CI 1.349–10.883, p=0.012) and SYNTAX score≥12 (OR=16.466, CI 5.225–15.889, p<0.001). At median follow-up of 26 months (IQR 17–35) the all-cause mortality was 17.5% in FFR positive bifurcations vs. 4.1% in FFR negative lesions (log-rank =.067).

Conclusions

Less than a half of angiographically significant coronary bifurcation lesions are functionally significant and require stent implantation. The functional significance was related with higher degree stenosis in main vessel and overall disease severity estimated with SYNTAX score. A trend to lower mortality was noted in group with non-significant FFRs.

[Identification the risk of preterm labor :the role of fetal fibronectin]

Fibronectins represent a group of glycoproteins, which form "molecular glue" and are necessary in the interaction between a cell and a cell. The existence of fetal fibronectin in pregnant woman's vagina up to 22 g.w. is normal. In a normally proceeding pregnancy between 22 g.w. and 35 g.w. there is not supposed to be found fetal fibronectin in cervico-vaginal secretion. Its presence is a highly informative biological marker for the risk of premature birth.

AIM

The aim of this research was to determine the risk for premature birth through applying fetal fibronectin test as a specific marker to pregnant women with or withthout symptoms of threatened birth.

METHODS

A prospective longitudinal study has been carried out. The tests have been applied to hospitalized patients in University hospital "Majchin dom", Clinic of Pathologic pregnancy and Delivery room. Tests have been applied on 116 patients in totally). The pregnant have been separated in two groups depending on the fact of presence or absence of premature birth symptoms. The screening methods used were: the fFN test and the cervical length measurement by transvaginal according to an established protocol.

CONCLUSION

From the total of 116 patients, in 78 we have received positive tests for fetal fibronectin; in 38 - negative test. With asymptomatic patients, having higher risk of preterm birth, the percent of positive tests has been lower (14%). With asymptomatic patients with higher percent of risk factors have been: short cervix (38%), multiple pregnancy (29%), followed by patients with diagnosis of preterm birth in the past (25%) and bleeding in earlier terms. Estimating positive and negative predictive rate, we have achieved following results: The test for fetal fibronectin has excellent predictive rate - 97%, which coincides with the great deal of research until this moment in the world. Referring to the positive predictive rate--it is not sufficient--only 19%.

[Macroscopic and histopathological changes in the fetal appendages as a factor in the pathogenesis of intrauterine fetal death ]

BACKGROUND

Intrauterine fetal death is an agonizing, often unpredictable event. Autopsies of stillborn fetuses, including placentas, umbilical cord and fetal membranes, are performed to clarify the cause of death. Autopsy results are not always easily understood by the patients and difficult to clarify by the specialists.

OBJECTIVE

To evaluate the macroscopic pathological and histopathological changes in placenta, umbilical cord and fetal membranes as a factor in the pathogenesis of intrauterine fetal death.

MATERIALS AND METHODS

Retrospective review of 129 autopsy reports of singleton stillborn fetuses and placentas from 23 to 41 weeks of gestation.

RESULTS

Macroscopic and histopathological findings in the placenta, often in combination with inflammatory changes prevailing in premature cases, while macroscopic and histopathological findings in umbilical cord predominate in term stillborn. In 11% of cases there were no specific pathological findings.

CONCLUSIONS

Pathological analysis of the placenta is essential for clarifying the pathogenesis of stillbirths. Simplifying the classification of pathological results of fetal appendages at autopsy categories--changes in the placenta, changes in the umbilical cord and inflammatory changes may contribute to easier interpretation and allows for comparison of results.

[Identification of preterm labor: the role of fetal fibronectin in parents with symptoms]

AIM

To determine whether the presence of fetal fibronectin in vaginal secretions of patients with symptoms suggestive of preterm labor predicts preterm delivery. Fetal fibronectin, a large molecular weight glycoprotein produced in the chorion, is expressed in cervical and vaginal secretions in women with disruption of the choriodecidual junction by labor or by inflammation.

METHODS

A prospective observational longitudinal study from January 2013 till December 2013 was performed on patients between 24 and 32 weeks of gestation with symptoms of preterm labor, intact membranes, and cervical dilation < 4 cm (total patients = 86). The endpoint was the delivery at 34 weeks or more. The screening methods used were: the fFN test and the cervical length measurement by transvaginal according to an established protocol.

CONCLUSION

The presence of FFN in vaginal or cervical secretions before 35 weeks is a is a strong predictor that preterm delivery is unlikely within the next 7 to 14 days. The predictive power of FFN is stronger at earlier gestation ages (24-29 wks) than it is later in pregnancy and is stronger for short-term prediction (7-14 d).

[Causes of stillbirths according to the period of pregnancy]

INTRODUCTION

Stillbirths represent 50% of all perinatal mortality and remain significant and unanswered problem.

OBJECTIVE

To investigate the causes of stillbirths in term and preterm fetuses and place of intrauterine growth retardation in the pathogenesis of antenatal death.

MATERIALS AND METHODS

The study was retrospective for the period 2008 to 2013, covers 217 cases of stillbirths in University Hospital "Maichin dom" Sofia. Gestational age was from 23 to 41 weeks. Inclusion criteria for the study were: antenatal occurred dead and singleton pregnancy. Exclusion criteria: fetal malformations and multiple pregnancies. Thus number of enrolled cases was 153.

RESULTS

The causes of stillbirths are different in different groups according gestational age. The cases of unknown cause, abruption of placenta and preeclampsia prevail in preterm group. The term stillborns headed with pathology of the umbilical cord, followed by cases of unknown cause, diabetes and infection. Overall, preterm group stillborn with mass below 10 percentile for the gestational age - 53 % predominate, compared with those born at term - 39%.

CONCLUSIONS

The incidence of stillbirths is higher in preterm than term born fetuses. The causes of antenatal death in preterm is mainly abruption of placenta and preeclampsia, whereas in term - pathology of the umbilical cord. In premature stillborn intrauterine growth retardation is more common in comparison with those on term. Unexplained antenatal fetal death is more common in preterm fetuses.

[Tocolysis with nifedipin; its use in current practice]

AIM

The aim of the study is to establish the safety and efficacy of calcium channel blocker- Nifedipin as tocolytic agents. A wide range of tocolytics have been utilized for the management of preterm labor Calcium channel blockers, namely nifedipine, gained popularity as tocolytics due to the oral route of administration, availability of immediate- and slow-release preparations, the low incidence of maternal adverse effects associated with their use, and the fact that they are inexpensive.

METHODS

88 pregnant women in preterm labor participated in a prospective longitudinal study Inclusion criteria were: gestational age between 24 and 34 weeks gestation; uterine contractions in 10-15 min interval; single pregnancy, lack of contraindications for tocolysis. In all cases the calcium antagonist Nifedipine was used in dosage 4 x 10 mg per os. The clinical response to tocolysis, gestational age at delivery and potential side effects were analyzed.

RESULTS

91 pregnant women participated in the study. Three were excluded because they refused to participate. 88 pregnancies were finally analyzed. In nine of them maternal contractions persisted despite of treatment. The other 79 pregnancies were delayed 48 hours to receive antenatal corticosteroids. From all these 79 pregancies 66 delayed 7 days. The most common adverse effects were tachycardia, hypotonia, headache, dizziness, but they escape soon after the first dose.

CONCLUSION

Nifedipine is an effective oral tocolytic with few maternal side effects.

[Perinatal mortality of IUGR neonates]

This study was conducted to evaluate the role of intrauterine fetal growth restriction (IUGR) in the perinatale mortality. A prospective study was designed, including 329 consecutive singleton pregnancies between 24 to 40 weeks' gestation, whose body weight is under 10th percentile for the gestational week. The control group consist of 530 appropriate for the gestational week (AGA) in the same period of gestation. The fetuses are without inborn malformations. The results show grater stillbirth rate in the group of hypotrophic than in the eutrophic neonates. In the group under 27th week of gestation is 2.6% forAGA and 8.3% for IUGR, for the group between 28-31 w.g. is 9.6% and 21.1% respectively and for 32-35 wg. is 2.3% against 13.1%. Perinatal mortality rate (stillbirth and demised before discharged) for the group before 27th w.g. is 65.8% for AGA and 72.2% for IUGR (P > 0.05). Between 28-31 w.g. is 28.4% and 50.0%, for 32-35 is 6.9% and 27.8% respectively (P > 0.01). After 37th w.g. perinatal mortality rate is less in AGA than in SGA fetuses. In conclusion the stillbirth rate is more frequent in IUGR fetuses than in AGA and frequencies is more pronounce in late preterm pregnancy. The fetal hypotrophy has deleterious effect on neonatal survival rate.

Impact of body mass index (BMI) and age on the outcome of the IVF process

BACKGROUND

The goal of this study was to examine the impact of body mass index (BMI) and age on the outcome of the IVF process.

MATERIALS AND METHODS

This was a retrospective case-control study, of all patients undergoing IVF from 2008-2010 in the Re-Medika IVF Centre. A total of 1238 fresh, non-donor IVF cycles were analyzed, but to minimize the bias, only the first cycle for each patient in that period was analysed (N-920). The patients underwent standard protocols for COH and embryology treatment. In all retrieved oocytes, or in 100% of the cases, the process of fertilization was realized with the method of intracytoplasmic sperm insemination (ICSI). The primary end-point assessed was clinical pregnancy rate. Patients were initially grouped into four BMI categories. The data are presented as frequencies (qualitative data) and as mean±SD (quantitative data). Preliminary comparisons between groups with different BMI were made by the Chi-square and one-way ANOVA test. Because fertility declines with age, there is a Pearson-correlation coefficient to see if BMI depends on age, and the resulting value r=0.15 (p<0.05) showed that BMI is age-dependent, the relationship between them showed multicollinearity. However, the calculated error tolerance of 0.9 indicates stability of the model. Furthermore, to adjust the known fertility decline with age, every response or outcome is analysed by the method of multiple linear (continuous data) or logistic (qualitative data) regression, where the independent variables are taken: BMI, age and BMI interaction×age.

RESULTS

Increased BMI significantly reduces the chance of clinical pregnancy (normal weight vs. overweight: clinical pregnancy rate: 49.2%, vs. 34.3%). Age, analysed as a single factor, significantly reduces clinical pregnancy rate. Interaction of BMI and age significantly affects clinical pregnancy rate. (BMI vs. BMI×Age vs. Age-p 0,01 vs. 0,001 vs. <0,0001).

CONCLUSION

Increased body mass of patients entering IVF has a negative impact on the final outcome and certainly reduces the success of the process resulting in reduced clinical pregnancy. Interaction of BMI and age showed a strong significant impact on the outcome of IVF seen through the achievement of clinical pregnancy.

Reproductive outcome after hysteroscopic metroplasty in patients with infertility and recurrent pregnancy loss

INTRODUCTION

Patients with uterine malformations have decreased reproductive potential and an unfavourable reproductive outcome starting even from the first pregnancy. Patients with untreated uterine malformations have a term delivery rate of 40%-65%. Hysteroscopic metroplasty is a standard, safe and minimally invasive method for treatment of uterine malformations, which provides a normal uterine cavity in patients with hysteroscopically correctible types of uterine malformations. The aim of the study was to analyse the variables associated with reproductive outcome before and after hysteroscopic metroplasty.

MATERIAL AND METHODS

We analysed the variables determining reproductive outcome after 216 interventions with hysteroscopic metroplasty in 202 patients which were done at the University Obstetrics and Gynecology Clinic in Skopje during a three-year period, from 01.01.2006 to 31.12.2008. Patients were divided into three groups: patients with recurrent pregnancy loss, patients with secondary infertility and foetal loss and patients with primary infertility. The follow-up period lasted for two years (24 months). Statistical analysis was performed using the Chi-square test and p<0.05 was considered to be statistically significant.

RESULTS

During the follow-up period of two years after hysteroscopic metroplasty there were a total of 113 pregnancies, of which 46 belonged to the group of primary infertility. Analysis of the reproductive outcome of those patients (compared before and after hysteroscopic metroplasty) showed a significant (p<0.05) decrease in the abortion rate from 89.6% to 12.4%, as well as an increase of term delivery rate from 1.4% to 74.4%. In the group of preterm deliveries there was a rise from 9% to 13.2%, which was not significant. The group of primary infertility had a pregnancy rate of 36%.

CONCLUSION

Hysteroscopic metroplasty significantly improves the reproductive outcome in patients with surgically correctible uterine malformation.

Elastic properties and structure of the radial artery in patients with type 2 diabetes

Alterations of elastic properties may contribute to the accelerated atherosclerosis in patients with T2D. Little is known, however, about radial artery distensibility in this patient group. A total of 19 patients with T2D and 19 controls were investigated.An echotracking system coupled to a plethysmograph was used to assess the morphologic and elastic properties of radial artery. Distensibility and compliance were evaluated using Langewouters' equations. Distensibility and compliance did not differ significantly in patients with diabetes compared with controls. In contrast, radial IMT and WCSA were significantly higher in patients with T2D than in controls. Multiple regression analyses revealed a significant association between SBP and IMT (r(2) = 0.40, p<0.001) as well as WCSA (r = 0.54; r(2) = 0.30; p<0.001 ) in individuals with diabetes. In conclusion, distensibility and compliance of the radial artery are not reduced in patients with T2D. In contrast, radial IMT and WCSA are significantly higher in patients with T2D than in controls.These modifications are chiefly and positively related to SBP.

[A new approach for discovering minimal residual disease in patients with operable breast cancer]

The striving of surgeon for achieving better long-term results of surgical treatment of patients with breast cancer put the searching of new independent prognostic factors for the exit of the treatment. This has become possible in the last decade of XX century when new diagnostic methods as immunochistochemistry, polimerase chain reaction (PCR), cytomorphology etc. entered the clinical practice. With bone marrow biopsy in patients with breast cancer earlier diagnosis of minimal residual disease is achieved, the approach to those patients is changed and a possibility for discovering women at higher risk is given. By immunochistochemistry method in the diagnostics of minimal residual disease in patients with breast cancer, more precise staging is achieved. This will change the therapeutic approach to these patients.

[Genetic changes in breast cancer - an overview]

Current understandings about development of breast cancer from genetic point of view are discussed. Information about the hereditary forms of cancer is presented. Different forms of screening and problems connected with their application are discussed.

[Radioimmunoguided surgery - a new stage of therapeutic management of oncological patients]

Thanks to the fast development of nuclear medicine and radiodiagnostics with highly informative techniques it became possible to use the application methods the surgical practice. The methods that are used the nowadays intraoperative techniques aim to help the malignant disease, to stage more precisely the process; to help visualisation of the metastases and to evaluate the volume of the used surgical techniques that highly informative. This is possible through the last 1-2 years by application monoclonal antibodies labeled by radioisotopes, whose specific accumulation is evaluated by the help of gamma-tetector probe (GDP).

Variability in the taxonomic characters of Black Sea gyrodactylids (Monogenea)

Variability of the haptoral hard parts of four Black Sea Gyrodactylus species (G. alviga Dmitrieva & Gerasev, 2000; G. crenilabri Zaika, 1966; G. flesi Malmberg, 1957; G. sphinx Dmitrieva & Gerasev, 2000) was studied in relation to season, host and geographical variability. A discriminant analysis was carried out on the measurements of 14 characters of the haptor of all four species. The haptoral hard parts of the investigated gyrodactylids decrease in size with an increase in water temperature. It is known that life-span of gyrodactylids is negatively correlated with water temperature and they exhibit peak intensities at low temperature. At the same time, life-span is considered to be a general indicator of a favourable environment. Therefore, high water temperature is not apparently advantageous for gyrodactylids. In the case of low marine salinity, in adapted species the sizes of the haptoral hard parts are larger at lower levels of salinity and vice versa for typical marine species. Lastly, in specimens parasitising the primary host, these features are larger than in those parasitising a secondary host. It is possible to say that, in general, the more favourable the environment for gyrodactylids the larger their haptoral hard parts. Unfavourable environmental conditions reduce the time of embryogenesis, which has a dual effect on gyrodactylids: positive in relation to their reproduction (by increasing the reproduction rate) and negative in relation to their development (by decreasing the size of the haptoral hard parts).

Evaluation of oxidative stress in patients with cancer

The oxidative stress is considered to be involved in the pathophysiology of cancers. In the current study we explored the oxidative stress in patients with different cancers and corresponding benign diseases by evaluation of the level of lipid peroxidation products (MDA level) in the plasma and the activity of erythrocyte antioxidant defense enzymes superoxide dismutase (SOD) and catalase (CAT). Significantly higher plasma levels of lipid peroxidation products were detected in patients with early and advanced cancers in comparison to the healthy volunteers (mean 3.1 micromol/l and 2.3 micromol/l, p = 0.0003 and p = 0.029, respectively, t-test). In addition, 10-20 days after radical operations of cancer patients with normal postoperative recovery period, the plasma levels of MDA decreased and reached values close to the controls (mean 2.0 micromol/l). SOD in erythrocytes of patients with benign diseases and malignant solid tumors before and after surgery did not differ from that of the controls. In contrast, CAT activity of patients with early cancers was found to be significant higher than that of the controls (mean 22157.2 U/gHb vs. 12832.0 U/gHb, p = 0.032, t-test). A decrease of CAT activity was observed after surgery (mean 15225.0 U/gHb). In conclusion, our results suggest the presence of an increased oxidative stress accompanied by a lack of changes of erythrocyte SOD activity and an adaptive increase of CAT activity.

Mouse BAC ends quality assessment and sequence analyses

A large-scale BAC end-sequencing project at The Institute for Genomic Research (TIGR) has generated one of the most extensive sets of sequence markers for the mouse genome to date. With a sequencing success rate of >80%, an average read length of 485 bp, and ABI3700 capillary sequencers, we have generated 449,234 nonredundant mouse BAC end sequences (mBESs) with 218 Mb total from 257,318 clones from libraries RPCI-23 and RPCI-24, representing 15x clone coverage, 7% sequence coverage, and a marker every 7 kb across the genome. A total of 191,916 BACs have sequences from both ends providing 12x genome coverage. The average Q20 length is 406 bp and 84% of the bases have phred quality scores > or = 20. RPCI-24 mBESs have more Q20 bases and longer reads on average than RPCI-23 sequences. ABI3700 sequencers and the sample tracking system ensure that > 95% of mBESs are associated with the right clone identifiers. We have found that a significant fraction of mBESs contains L1 repeats and approximately 48% of the clones have both ends with > or = 100 bp contiguous unique Q20 bases. About 3% mBESs match ESTs and > 70% of matches were conserved between the mouse and the human or the rat. Approximately 0.1% mBESs contain STSs. About 0.2% mBESs match human finished sequences and > 70% of these sequences have EST hits. The analyses indicate that our high-quality mouse BAC end sequences will be a valuable resource to the community.

The discrimination of abrupt changes in speed and direction of visual motion

A random dot pattern that moved within an invisible aperture was used to present two motions contiguously in time. The motions differed slightly either in speed (Experiments 1 and 3) or in direction (Experiments 2 and 4) and the subject had to discriminate the sign of the change (e.g. increment or decrement). The same discrimination task was performed when the two motions were temporally separated by 1 s. In Experiments 1 and 2 discrimination thresholds were measured with motion durations of 0.125, 0.25, 0.5 and 1.0 s and mean speeds of 2, 4, 8, and 16 degrees/s. In Experiments 3 and 4 thresholds were measured with aperture widths of 5 and 20 cm. The discrimination of contiguous motions progressively deteriorated with decreasing duration and mean speed of motion. For the lowest value of duration the Weber fraction for contiguous speeds was more than three times as the Weber fractions for separate speeds. For the same low value of duration the thresholds for discrimination of direction of contiguous motions were only about 50% higher than the thresholds for separate motions. The Weber fraction for contiguous speeds was ca. three times higher with the smaller aperture than with the larger one, provided the ratio 'aperture width mean speed' (i.e. the lifetime of the moving dots) was less than 0.3 s. Aperture width did not affect the discrimination of direction of contiguous motions. The discrimination of contiguous motions is discussed together with the known data for detection of changes in speed and direction. It is suggested that both, detection of changes in speed and discrimination of the sign of speed changes, may be performed by a common visual mechanism.

[Breast cancer and pregnancy]

Breast carcinoma is a condition characterized by an ever increasing incidence. Young women too are ever more frequently involved. Currently a modern tendency is observed of young women to postpone conception for a later period of life on account of a number of socioeconomical reasons, which tendency tangibly augments the number of women affected with breast cancer during the pregnancy period. Most of the pregnant women are in the age group 34 to 35 years. Breast cancer during pregnancy is a malignant disease ranking second by incidence rate. The latter amounts to 10-30 per 100,000 of pregnant women.

Discrimination and Detection of Changes in the Velocity of Visual Motion: Effect of Aperture Size

Recently Mateeff and Hohnsbein (1996 Vision Research36 2873 – 2882) showed that the critical frequency for detection of modulated velocity of motion was invariant with respect to the viewing distance. The critical frequency was a function of the ratio between the mean velocity and the size of the aperture through which the motion was observed. In the present study we examined whether the velocity/aperture ratio affects velocity discrimination and detection of single velocity changes. Six subjects observed a random-dot pattern that could move within an invisible square aperture. In the discrimination task, two motions of 250 ms duration with slightly different velocities were presented with a 1 s interval between them. The subject had to report which of the motions was faster. In the change-detection task the same two motions were presented without an interval between them and the subject had to report whether the change was from a low to a high velocity or vice versa. Mean velocities of 8 and 64 deg s−1 and aperture sizes of 10 and 40 deg were employed in both tasks. Weber fractions were determined by the method of constant stimuli. The discrimination accuracy was not affected by aperture size at either mean velocity. The detection task was also unaffected by aperture size at 8 deg s−1. However, at 64 deg s−1 decreasing aperture size impaired the Weber fractions by a factor of about three. We suggest that the decrease of the lifetime of the dots of the pattern at high velocities and small apertures may be the critical factor for the impairment of the change detection. This factor is of less importance for the velocity discrimination task.

What determines the detection of changes in motion velocity? A comment on Dzhafarov, Sekuler, and Allik (1993)

We comment on a recent model aimed at explaining data on speed of reaction to motion onset and to changes in motion velocity. The model is based on calculating the running variance of the stimulus positions passed during the motion. We show that although the model is successful in explaining data on motion onset and suprathreshold velocity changes, it may not be able to explain data on time of reaction to changes in velocity when these are near the detection threshold.

[Intraoperative abdominal echography]

Experience with and the impressions of adopting intraoperative abdominal echography in eighteen patients, aged 26 to 73 years, 9 men and 9 women, are shared. The distribution of patients by pattern of diseases is as follows: colorectal carcinoma--4 cases, liver echinococcus--one, gastric carcinoma--one, hepatocellular carcinoma--one, cholangitis acuta purulenta-one, echinococcus of lung and liver--one, calculous cholecystitis with choledocholithiasis--five, and carcinoma of ductus choledochus--one. Fifty intraoperative abdominal echographies and one intrathoracic supradiaphragmatic echography of the liver are performed. Intraoperative abdominal echography of tumors involving organs of the digestive tract contributes to specify the staging of the neoplastic process. In liver echinococcus it determines precisely the number of cysts and diagnoses impalpable cystic formations, while in choledocholithiasis it documents the presence of calculi in the biliary tracts and eventual dilatation of intrahepatic ones. In five patients intraoperative abdominal echographic is done in conjunction with intraoperative fiber choledochoscopy.

Temporal thresholds and reaction time to changes in velocity of visual motion

A random dot pattern moved at a velocity V1. The velocity then increased or decreased abruptly to another value V2 for some time and again returned to V1. The temporal threshold, i.e. the duration of V2 that was necessary to detect the change was measured. Thresholds for the detection of the same velocity increment, V2 = 2 x V1, were shorter when the baseline velocity V1 increased from 1 to 8 deg/sec (Expt 1). The temporal threshold decreased as the velocity contrast (V2 - V1)/(V1 + V2) increased from 0.33 to 0.77. The thresholds for the detection of velocity decrements were in general longer than those for the detection of increments (Expt 3). In Expts 2 and 4 the random-dot pattern moved with velocity V1, which abruptly increased or decreased to V2, without returning to V1. The reaction time to the change was measured for the same velocity pairs as those used in the temporal threshold measurements. There was a good correspondence between changes in the reaction times and changes in the thresholds under the various conditions. The data are interpreted on the basis of two hypotheses: higher velocities are detected by mechanisms that respond more rapidly; and integration of velocities occurs when temporally-adjacent motions are presented.

Use of subcutaneous implantable infusion systems in neoplastic and AIDS patients requiring long-term venous access

OBJECTIVE

To evaluate the life span and complication rates of totally implantable infusion devices in patients with short bowel syndrome and in immunocompromised patients with AIDS, lymphoma, and myeloma who required long-term central venous access.

DESIGN

Prospective open study.

SETTING

University hospital, Italy.

SUBJECTS

Group I - 5 patients with short bowel syndrome; group II - 11 patients with AIDS; and group III - 15 patients with lymphoma or multiple myeloma (1 of whom had 2 devices implanted).

MAIN OUTCOME MEASURES

Duration of implantation and incidence of catheter-related complications.

RESULTS

The mean duration/patient of the catheter was 422 days (range 20-1257) in group I; 104 days (range 43-262) in group II; and 415 days (range 62-1280) in group III. There were no catheter related complications in the patients in group I (short bowel syndrome). Of the 11 patients with AIDS (group II) 4 developed catheter related infections (0.32/100 catheter days), and 1 developed a thrombotic occlusion. All 5 catheters were removed (3 for infection). Of the 15 patients with lymphoma or myeloma who had 16 catheters implanted (group III), 1 patient developed 3 infective episodes (0.05/100 catheter days), 1 catheter migrated and 1 occluded. All 3 catheters were removed.

CONCLUSION

Totally implantable infusion systems can safely be used for prolonged periods in immunocompromised patients, including those with AIDS if their life expectancy is reasonable.

Sensitivity of 5'-nucleotidase and phospholipase A2 towards liver plasma membranes modifications

The changes in the phospholipid and fatty acid composition of liver plasma membranes isolated from rats, fed two different diets, containing either saturated or unsaturated fatty acids, were investigated. We established that dietary treatment can considerably modify the fatty acid as well as the phospholipid composition of liver plasma membranes. Lipid transfer proteins were used for enrichment of liver plasma membranes with sphingomyelin, dioleoylphosphatidylcholine, dipalmitoylphosphatidylcholine, and phosphatidylinositol. A marked sphingomyelin and membrane fluidity dependence of the membrane-bound 5'-nucleotidase and phospholipase A2 was observed.

Retinal location and visual localization during pursuit eye movement

Experiments were performed to measure the mislocation of a brief visual stimulus presented during pursuit eye movements in different places over the retina. The results obtained show that the mislocation for regions 5 degrees from fovea in the direction of motion is greater than in fovea. This fact shows that some kind of reorganization takes place in the visual localization mechanisms during pursuit eye movements. The results cast doubts on the concept of "perception time" which is often used to explain the visual mislocation phenomenon.

Localization of brief visual stimuli during pursuit eye movements

Experimental findings concerning the properties of the phenomenon of mislocation of brief visual stimuli during smooth eye tracking are described. One of these, which cannot be explained by existing hypotheses, is that under certain conditions the mislocation magnitude tends to have zero or even negative values. A model is developed for explanation of the mislocation phenomenon. It is suggested that localization is based on: (1) information about the current eye position and (2) information about the stimulus locus on the retina. They both arrive at the localization centre with non-zero delays. The mode of information processing in this centre leads to a magnitude of mislocation which is proportional to the difference between the two delays and which could be positive, zero or negative. Factors which influence either delay should also influence the mislocation magnitude.

Insulin effect on lung subcellular fraction phospholipids and cholesterol

Lung subcellular fraction (microsomes, mitochondria, 105 000 X g supernatant and plasma membranes) were isolated from normal and insulin treated rats. Phospholipid and cholesterol contents were determined, phosphatidylcholines and phosphatidyl-ethanolamines separated and their fatty acid profiles assayed. Teh investigations carried out indicated that insulin influenced the phospholipid content of all fractions. Cholesterol levels in the 105 000 X g supernatant and especially in the plasma membrane fraction were raised significantly. Insulin administration increased the contribution of the unsaturated long chain fatty acids in both phospholipids studied. The results are discussed in relation to stimulated lipid biosynthesis and to lipid fluidity, of which fatty acyl unsaturation and cholesterol level are main parameters.

Some temporal characteristics of eye tracking

The frequency of occurence and the latency of eye tracking determined by moving stimuli of different velocities (5, 10 and 15 degrees/s) and different durations (between 50 and 400 ms) were measured. The result was that eye movement can occur only if the duration of the stimulus exceeds a critical value. This value depends on the stimulus velocity. The difference between the latency of the movement and the critical duration of the stimulus however remains constant. This difference is interpreted as the time necessary for selecting and releasing the appropriate programme for eye movement.

[Effect of prolonged hyperoxia on rabbit lung lipids and their fatty acid content (author's transl)]

The effect of a 36-hour hyperoxia (60 % oxygen) on rabbit lung lipids has been investigated. It has been established that hyperoxia leads to the increase of all lipid fractions in lung tissue and alveolar surfactant, phospholipid and cholesterol being most significantly affected. It has also been found that hyperoxia leads to the decrease of palmitic acid and to the increase of linoleic and arachidonic acids almost in all lipid fractions. Marked changes in the positional distribution of fatty acids in alveolar surfactant phosphatidylcholine have also been observed. The possible mechanisms of the effect of oxygen on lung lipid metabolism have been discussed, and the consequences ensuing from it which could affect the structural organization of membranes have been evaluated.

Positional distribution of fatty acids in rabbit lung phospholipids and triacylglycerols and effect of prolonged hyperoxy

Investigations have been carried out for the determination of the effect of high oxygen concentration in inspired gas mixutre on the positional distribution of fatty acids in rabbit lung phospholipids and triacylglycerols. The following results were obtained: 1. In the phosphatidylcholine fraction, the high oxygen concentration caused a quantitative increase of palmitic acid (16 : 0) at the alpha-position, and of myristic (14 : 0), heptadecenic (17 : 1) and arachidonic (20 : 4) acids at the beta-position. 2. In t-e phosphatidylethanolamine fraction, the high oxygen concentration caused an increase of oleic acid (18 : 1) at the alpha-position, and of palmitoleic (16 : 1) and heptadecenic (17 : 1) acids at the beta-position. 3. In the triacylglycerol fraction such changes were not observed. In connection with these effects of oxygen, its possible influence on membrane structures in the lung has been discussed.