Showing papers by "University of Rijeka published in 1998"

Hierarchical and redundant lymphocyte subset control precludes cytomegalovirus replication during latent infection

Abstract: Reactivation from latent cytomegalovirus (CMV) infection is often associated with conditions of immunosuppression and can result in fatal disease. Whether the maintenance of systemic CMV latency is mainly governed by factors of the infected cell or by immune control functions is unknown. Likewise, the putative immune control mechanisms which could prevent the induction and spread of recurrent CMV infection are not clearly identified. We took advantage of latently infected B cell–deficient mice and a sensitive method for virus detection to study CMV reactivation after ablation of lymphocyte subsets. A crucial role of both T lymphocytes and natural killer (NK) cells was demonstrated. Within 5 d after depletion of lymphocytes, productive infection occurred in 50% of mice, and 14 d later 100% of mice exhibited recurrent infection. A hierarchy of immune control functions of CD8+, NK, and CD4+ cells was established. Reactivation was rare if only one of the lymphocyte subsets was depleted, but was evident after removal of a further subset, indicating a functional redundancy of control mechanisms. The salivary glands were identified as the site of most rapid virus shedding, followed by the detection of recurrent virus in the lungs, and eventually in the spleen. Our findings document a previously unknown propensity of latent CMV genomes to enter productive infection immediately and with a high frequency after immune cell depletion. The data indicate that only the sustained cellular immune control prevents CMV replication and restricts the viral genome to a systemic state of latency.

Virus Attenuation after Deletion of the Cytomegalovirus Fc Receptor Gene Is Not due to Antibody Control

Abstract: The murine cytomegalovirus (MCMV) fcr-1 gene codes for a glycoprotein located at the surface of infected cells which strongly binds the Fc fragment of murine immunoglobulin G. To determine the biological significance of the fcr-1 gene during viral infection, we constructed MCMV fcr-1 deletion mutants and revertants. The fcr-1 gene was disrupted by insertion of the Escherichia coli lacZ gene. In another mutant, the marker gene was also deleted, by recombinase cre. As expected for its hypothetical role in immunoevasion, the infection of mice with fcr-1 deletion mutants resulted in significantly restricted replication in comparison with wild-type MCMV and revertant virus. In mutant mice lacking antibodies, however, the fcr-1 deletion mutants also replicated poorly. This demonstrated that the cell surface-expressed viral glycoprotein with FcR activity strongly modulates the virus-host interaction but that this biological function is not caused by the immunoglobulin binding property.

Studies of acoustic streaming in biological fluids with an ultrasound Doppler technique

Abstract: Acoustic streaming generated by diagnostic ultrasound fields is an important area for study both for safety reasons and because of its potential application as a diagnostic tool. A method of investigating streaming in biological fluids is reported. A number of fluids were insonated using a 3.5 MHz weakly focused single element transducer which was driven in pulsed mode. Streaming was detected in each fluid using an 8 MHz continuous wave Doppler system. The maximum streaming velocity was obtained by spectral analysis of the Doppler signal. Using this system longitudinal streaming profiles were measured. At an acoustic power of 150 mW the maximum streaming velocities detected were: 9.3 cm s-1 in water, 6.8 cm s-1 in 4.5% human serum albumin (HSA) solution and 4.9 cm s-1 in blood, when transmission was through a water path of approximately 10 cm into a 3 cm sample of fluid. When measurements were made in the biological fluids alone, without a water path, the maximum streaming velocities were reduced.

Chromosomal Anomalies in Abnormal Human Pregnancies

Abstract: Objective: The aim of this study was to describe the cytogenetic observations on abnormal human pregnancies (anembryonic pregnancy, early fetal loss, and hydatidiform moles), and to

Comparison of microvessel density with tumor associated macrophages in invasive breast carcinoma.

Abstract: Neovascularization, the growth and formation of capillary blood vessels, is an essential component of solid tumor growth and a critical step in metastasis. Tumor associated macrophages (TAMs) have several functions related to tumor biology including growth, proliferative rate, stroma formation and dissolution, and neovascularization. The aim of this study was to define the TAM and microvessel density (MD) in human invasive breast carcinoma NOS and to correlate their values with lymph node status, tumor size, tumor grade and mitotic activity index (MAI), and, finally, to determine whether MD is connected with TAMs. A total number of 57 invasive breast carcinomas NOS were processed for immunohistochemical analysis using mAb to F-VIII to visualize endothelial cells and mAb to CD68 antigens for macrophages. Statistical analysis showed only a positive correlation between TAMs and MAI (p = 0.004). These results support the notion that intensity of tumor angiogenesis does not provide additional prognostic significance, while TAMs may play a positive role in breast cancer micro system since they regulate tumor proliferation.

Norms for 439 action events: familiarity, emotionality, motor activity, and memorability.

Abstract: A total of 128 male and female university students having Swedish as their mother tongue rated 439 actions on a 7-point scale in the dimensions of Familiarity, Emotionality, Motor Activity, and Memorability under instructions to imagine themselves performing each action (e.g., "to roll a ball", "to break a match"). Overall mean ratings were higher for women than for men in all four dimensions. High reliabilities were obtained in each scale. Intercorrelations between the dimensions were low to moderate, indicating that different characteristics of the actions were assessed. It is demonstrated that the ratings of the four dimensions are in agreement with previous categorisations of actions along the same or similar dimensions and with findings related to memory performance. Furthermore, control studies performed on the Familiarity dimension show that norm values are highly correlated with ratings given by participants in standard enacting and nonenacting conditions and with ratings in a condition where objects were present. These norms offer possibilities to control for and vary item characteristics of importance in the study of actions and the memory of actions. Language: en

Triply differential cross section for Compton scattering

Abstract: The triply differential cross section for Compton scattering from atomic electrons is obtained numerically in a full relativistic second-order $S$-matrix calculation based on the independent particle approximation. We compare our results with the results of more approximate approaches. Special attention is paid to the validity of the impulse approximation (IA), which has often been used for calculating the doubly differential cross section even when the photon momentum transfer K is similar to the average momentum ${p}_{\mathrm{av}}$ of the bound electron, which is ionized (and IA is found to be fairly accurate even in such circumstances). We here show that, on the contrary, IA calculations of the (less averaged) triply differential cross section are quite inaccurate for $|\mathbf{K}|\ensuremath{\sim}{p}_{\mathrm{av}},$ even near the peak in the triply differential cross section (where the free kinematics for scattering from an initial free electron at rest are satisfied and where IA should work the best). We conclude that electron momentum distribution determination through the Compton profile, using the doubly differential cross section, is more accurate at lower energies than direct determination through the measurement of the triply differential cross section at the same energy. In addition, viewing the total cross section for double ionization in Compton scattering as another observable less averaged than the doubly differential cross section in single ionization, we estimate that IA predictions of the total cross section for double ionization in Compton scattering from Helium are adequate above about 50 keV.

The value of an operating microscope in peripheral nerve repair. An experimental study using a rat model of tibial nerve grafting.

Abstract: The aim of this study was to test the hypothesis that the use of an operating microscope improves the results of peripheral nerve repair. Tibial nerve grafting was carried out on 48 Fischer rats divided into 2 groups: in one, a loupe was used, and in the other a surgical microscope. At 5 months after grafting, recovery was evaluated by functional, electromyographic, and morphometric tests. The mean motor nerve conduction velocity was 26.77±9.37 m/sec in the group where the loupe was used compared with 44.19±11.36 m/s when the microscope group was used. The soleus muscle weight and the diameter of myelinated fibres also confirmed better regeneration in the microscope group. These results clearly indicate that it is essential to use the microscope for peripheral nerve repair.

Incidence and prevalence of myasthenia gravis in the county of the coast and gorski kotar, croatia, 1976 through 1996

Abstract: For the period 1976 through 1996, we carried out an incidence and prevalence study of myasthenia gravis in the County of the Coast and Gorski kotar, Croatia. This was the first epidemiological study o

The influence of carbon source on the level and composition of ceramides of the Candida lipolytica yeast

Abstract: Candida lipolytica yeast was grown batchwise on two different carbon sources, glucose and n-hexadecane. Free ceramides were quantitatively isolated from sphingolipid fractions of total lipids by a combination of column chromatography and preparative thin-layer chromatography. Their composition, after acid methanolysis, was analysed by gas-liquid chromatography. The ceramide content accounted for 2.6% of the total cell lipids in hexadecane-grown cells, which was 1.5 times higher than in glucose-grown cells. The fatty acid composition of ceramides was characterized by the predominance of fatty acids shorter than 20 carbon atoms and by high concentrations of fatty acids with 16 carbon atoms after growth on both carbon sources. The dominant fatty acid was hydroxylated 16:0 in the glucose-grown cells and 16:0 in the hexadecane-grown cells. The striking finding was the low degree of fatty acid hydroxylation and relatively high proportion of odd-numbered fatty acids in ceramide of the n-hexadecane-grown cells. The ceramides contained an unusual long-chain base composition. In hexadecane-grown cells more than 60% of the long-chain bases were C19 phytosphingosine. In glucose-grown cells more than one-half of the total long-chain bases were tetrahydroxy bases, 4,5-dihydroxysphinganine and 4,5-dihydroxyeicosasphinganine.

Arterial Hypertension in Correlation with Age and Body Mass Index in Some Occupational Groups in the Harbour of Rijeka, Croatia.

Abstract: The research was carried out among 3787 workers in the harbour of Rijeka (Croatia), divided into six professional groups: harbour-transportation workers, administration staff, warehouse and assistant workers, artisans, motor vehicles drivers and seamen aboard the tugboats. The prevalence of arterial hypertension (AH) in relation to age and body mass index (BMI) was analysed. Significant correlation between prevalence of AH and age (r = 0.97) and between prevalence of AH and BMI (r = 0.98) was proven. Prevalence of AH for all the subjects was 10.6%. The lowest prevalence (7.3%) was established for harbour-transportation workers, who were the youngest on average and who were of lowest mean value of BMI. The highest prevalence of AH (16.6%) was for the warehouse and assistant workers, who were the oldest on average and were of highest mean value of BMI. Those differences were statistically significant in relation to other groups but in relation to the average age and the average values for those professional groups they fitted into the expected values. Results did not confirm positive relationship between potentially harmful working conditions of the surveyed professions and the development of AH. Age and BMI as reliable predictors of AH were pointed out.

Screening for Down's syndrome and neural tube defect in Croatia. A regional prospective study.

Abstract: Objective: The purpose of this study was to investigate the efficiency of second-trimester maternal serum screening for Down’s syndrome and open neural tube defects using alpha-feto

Education in clinical pharmacology at the Rijeka School of Medicine, Croatia

Abstract: Objective: Irrational drug prescribing is a global problem that exists both in developed and developing countries. Education is the key to improved effectiveness and safety in drug therapy. Development of clinical pharmacology (CP) as an independent discipline at the Rijeka School of Medicine has been slow and unsatisfactory. It was taken only as a part of some postgraduate courses. In the 1995/1996 academic year clinical pharmacology was offered for the first time to sixth year medical students as a non-mandatory subject. The purpose of this study was to emphasize the importance of education in clinical pharmacology at the Rijeka School of Medicine. Methods: This survey was an uncontrolled study based on responses to questionnaires and a test consisting of written patient problems given to sixth year medical students and to general practitioners who were following a course in clinical pharmacology. Results: The results of the questionnaire showed that both undergraduate and postgraduate students consider that they are not being adequately trained to prescribe drugs rationally and that they believe that clinical pharmacology should become a mandatory subject in the undergraduate medical curriculum. The results of the written patient problem test support this. Both groups of students demonstrated greater skills in solving the diagnostic part than the therapeutic part of the test. A great improvement in the students' ability to solve the therapeutic part was observed after they had completed the CP course. Conclusion: The results of this survey underline the necessity of education in clinical pharmacology.

Tissue zinc dynamics during the immune reaction in mice

Abstract: Owing to the importance of zinc for the functioning of the immune system, the role of endogenous Zn, located both in lymphoid and nonlymphoid organs, was investigated during the standard humoral and cellular types of immune response. For this purpose, the dynamics of hepatic, thymic, splenic, and renal Zn content was determined in mice sensitized with (a) sheep red blood cells and (b) semiallogeneic lymphocytes during the local host vs graft reaction (HVGR). The data obtained by ion-coupled plasma spectrometry revealed that the humoral type of immunity is characterized by a significant increase of Zn concentration in the liver and in the thymus. Simultaneously, linear regression analysis showed that the generation of plaque-forming cells in the individual mouse was highly positively correlated with Zn concentration in the liver (r=0.897), and spleen (r=0.833), and negatively with Zn concentration in the thymus (r=-0.624). Similar relationships between the intensity of local immune reaction and tissue Zn levels were found in local HVGR at the fifth day in the liver and spleen (r=0.861 and r=0.695, respectively), at the seventh day in the thymus (r=-0.797), and at the tenth day in the liver (r=-0.859). The data emphasize the necessity of Zn for the development of normal immune response and point to the existence of a Zn-dependent hepato-thymic axis during the humoral and cellular types of immune reactivity.

Orthodontic anomalies in primary and permanent dentition--a longitudinal study.

Abstract: This research has intention to examine the stability and the changes of the Classes from the period of primary to permanent dentition on longitudinally examined subjects. The sample consisted of 246 children (132 boys and 114 girls) with orthodontic anomalies in primary dentition that were not orthodontically treated until the ensuing visit made by the same orthodontist in permanent dentition. 71.9% of the examined children (72.7% boys and 71.0% girls) registered no Class changes within the analysed period. Between boys the falling of the Class I occlusion, from primary to permanent dentition is unsignificant, but between girls Class I occlusion is falling significant and grow Class II malocclusion. In boys 29.2% of changes occurred in Class I occlusion of which 25.0% were brought to Class II while 4.2% to Class III malocclusion. In girls from 32.9% changed Class I occlusion, 28.9% changed into Class II, and 3.9% into Class III malocclusion. The Class II malocclusion during the development of dentition is more stable than the Class I occlusion.

Organization and activity of the health service in the Croatian province of Lika in the first year of the war.

Abstract: The aim of this report is to present the various aspects of the reorganization of the health service in the Croatian province of Lika during the first year, 1991-1992, of the war in Croatia. In the former Socialist Republic of Yugoslavia, the health service was completely in the hands of the state, and Croatia was not able to transform it in the first year of its independence. The paper documents the personnel, supplies, and equipment that the health service of Lika had at its disposal in the first year of the war, the division of the health service into the stationary and front-line medical corps, and the evacuation protocols developed to transfer surgical patients to the rear-area hospital. The response of the health service allowed for rapid and successful patient treatment, emphasized by the fact that the usual time elapsed between wounding and delivery of the patient to the operating table was less than 30 minutes. All surgeries, with the exception of those involving severe cranio-cerebral injuries, were performed in the war hospitals of Lika. After stabilization of their postoperative condition, generally within 30 minutes, patients were evacuated to the rear-area hospital in Rijeka, with artificial respiration. The distance by road from the war hospitals in Otocac and Gospic to the rear-area hospital in Rijeka was 120 and 170 km, respectively. Collectively, the results of our work demonstrate that a non-military health service can be transformed successfully and efficiently into a war medical service. Yet, we believe that this is possible only under the extreme conditions of a defensive war.

Environmental Proactiveness in an Eastern European Transition Economy

Abstract: Many Eastern European countries suffered decades of environmental neglect. As these countries' economies struggle to make the transition to free market economies, environmental proactiveness may be able to provide a crucial mechanism for economic and environmental development. This study explored the nature of environmental proactiveness and some of the related factors by conducting in-dept interviews with 30 companies across Croatia, Slovenia and Italy. Results from interviews suggest firms in Croatia and Slovenia may be developing environmentally proactive actions in a similar manner to firms in developed free market economies. Management attitudes toward the environment and management uncertainty about taking environmental actions were strongly related to environmental proactiveness and environmental proactiveness was related to performance of the firm. Market orientation did not appear to be directly related to environment's environmental attitude and management's uncertainty about environmental actions.

Democracy and charisma

Abstract: Termin karizma najprije se pocinje rabiti u teoloskim spisima. U starozavjetnoj literaturi taj se termin pojavljuje samo dva puta. U Novom zavjetu se, međutim, pojavljuje sedamnaest puta. Rabi ga Sv. Pavla, između ostaloga, u Drugoj poslanici Korincanima. U politickom kontekstu rijec karizma se napose rabi prilikom analize nacionalsocijalistickih i staljinistickih režima. Karizmatska legitimacija je ponajprije obilježje raznih tipova diktatura, a ne demokratske, ustavne države. Vjerojatno je i zbog toga nazocna negativna slika karizmatskoga konteksta u vecem dijelu suvremene drustvene teorije.

Glaucoma simplex congenitum in the Veli Brgud village, the Opatija County, Republic of Croatia--a genealogical nine-generation study.

Abstract: On the Ucka hill-side, in the Veli Brgud village, Opatija County, Istrian peninsula, Republic of Croatia, there is a great number of patients with glaucoma simplex congenitum (open angle glaucoma) among a total of 550 Croatian inhabitants. Of these, 536 (97.5%) were ophthalmologically examined and glaucoma simplex congenitum was diagnosed in 74 persons, some of them already blind. The proportion of the affected was 13.8%. The cases were largely from the Afric family (nicknamed "Sor"). The pedigree of the Afric-"Sor" family has 1215 members through nine generations, descendants of Matheus Afric (1762) and Marija Bratovic (1765). In the total of 536 examined, 291 (54%) belong to this pedigree, whereas 67 (90%) out of 74 affected persons were of the same pedigree. The rest of 7 (9.46%) affected patients did not descend from this pedigree, however, three of them (4.05%) were also from the Afric-"Sor" family, but we could not find a connection with that pedigree due to inadeguate marital data before 1760. In the Veli Brgud village, there also were 4 (5.41%) patients of non-Afric families with no other affected members. From the total of 330 marriages, 73 (22%) were consanguineous. According to our results, the mode of inheritance of glaucoma simplex in the Afric-"Sor" pedigree was of a dominant pattern.