Nanolitre liquid patterning in aqueous environments for spatially defined reagent delivery to mammalian cells.

Microscale biopatterning enables regulation of cell-material interactions and cell shape, and enables multiplexed high-throughput studies in a cell- and reagent-efficient manner. The majority of available techniques rely on physical contact of a stamp, pin, or mask with mainly a dry surface. Inkjet and piezoelectric printing is carried out in a non-contact manner but still requires a substantially dry substrate to ensure fidelity of printed patterns. These existing methods, therefore, are limited for patterning onto delicate surfaces of living cells because physical contact or substantially dry conditions are damaging to them. Microfluidic patterning with laminar streams does enable non-contact patterning in fully aqueous environments but with limited throughput and reagent diffusion across interfacial flows. Here, we describe a polymeric aqueous two-phase system that enables patterning nanolitres of a reagent-containing aqueous phase, in arbitrary shapes, within a second aqueous phase covering a cell monolayer. With the appropriate medium formulation, reagents of interest remain confined to the patterned phase without significant diffusion. The fully aqueous environment ensures high reagent activity and cell viability. The utility of this strategy is demonstrated with patterned delivery of genetic materials to mammalian cells for phenotypic screening of gene expression and gene silencing.

Epidemiological investigation of school-related injuries in Koprivnica County, Croatia.

AIM: To assess the prevalence of injuries in elementary schools and determine specific risk groups of school-age children. METHODS: According to the 1991 census, there were 6,398 children between 7 and 14 years of age in the study area of the former Koprivnica district. During the 1992-1997 period, 354 children were injured in school. The registration of injured children was performed via structured questionnaires filled out at the emergency clinic and outpatient surgical clinic of the General Hospital in Koprivnica. The mechanism of accident and activities preceding it were categorized according to the Nordic Medico-Statistical Committee classification. Chi-square test was used to determine groups of school children at specific risk and a classification tree was made on the basis of minimum entropy values for age, sex, activity, and mechanism of injury. RESULTS: The highest injury rate of was recorded in 12-year-olds (21.7%). Upper extremities were most common site of injury (52.8%), whereas the most common type of injury was contusion (45.2%). The rate of head injuries was 3.2 times higher in younger (aged 7-10) children, whereas the rate of sports injuries was 3.5-fold higher in older (aged 11-14) children (p=0.001). Entropy classification revealed younger school-age children to be at the highest risk of contusion due to a blow from a ball, an object, or contact during sports activities. CONCLUSION: In Koprivnica County, most school-related injuries occurred during sport activities (42%) and play during recess (55%), with specific differences in age and sex.

Cancer incidence in eastern Adriatic isolates, Croatia: examples from the islands of Krk, Cres, Losinj, Rab and Pag.

As an extension of previous research this study investigates the incidence of cancer in five genetic isolate island populations of the Eastern Adriatic, Croatia. Thorough anthropological research over the past three decades has established some of those populations as outstanding examples of genetic isolates. A previous study which found higher cancer incidence in 5 Eastern Adriatic islands than in a control population supported a hypothesis that among the founders of these populations there were genetic variants (especially with recessive inheritance) responsible for genetic susceptibility to certain types of cancer. This study sought to investigate cancer incidence in 5 further island populations. All cancer cases in five island populations (Krk, Cres, Losinj, Rab and Pag) over the 20-year period (1971 to 1990) was extracted from the data of the Croatian Cancer Registry. The mainland populations of Istrian and Primorsko-Goranska County, characterized by similar environmental factors but an outbred genetic structure, represented a control population. After standardization by by sex and age, cancer incidence was higher in the island populations than in the control population in both sexes. The cancer sites primarily responsible for the excess incidence were prostate, stomach and pancreatic cancer in males, and ovarian, breast, stomach, bowel, and brain cancer in females. The reasons for the increased cancer incidence are uncertain and may be due to different environmental exposure between the two populations. However, it is possible that genetic isolation and inbreeding are important factors. Further investigations of cancer in these isolate populations are warranted to explore these findings further.

Surname as 'cancer risk' in extreme isolates: example from the island of Lastovo, Croatia.

The aim of this study was to analyze whether there are surnames which appear more frequently among the ancestors of cancer cases in a small isolate, in comparison to the ancestral surnames of the healthy controls, using the classic case-control design. The chosen setting was the island of Lastovo, Croatia, located more than 100 kilometers from the nearest coastal region. The period of study was 1970-1995, during which a total of 76 cancer cases were recorded in a population of approximately 800. The comparison of surname frequencies was performed in current and in five ancestral generations. The leading hypothesis was that, if inbreeding and common ancestry contributed to the development of the disease, then those phenomena should be reflected in increasing frequency of some surnames among ancestors, identifying the 'hidden' consanguinity, or 'following' cancer-promoting genes on the Y-chromosome. The results imply that there are surnames representing a classic "risk" for cancer, but also those "protecting" from its development, which all underscores the importance of founder effect and genetic predisposition to the disease in a small, reproductively isolated population. All of the results become more evident and increasingly significant when analyzed in more distant ancestral generations.

Recovery of atrial systolic function after pharmacological conversion of chronic atrial fibrillation to sinus rhythm: a Doppler echocardiographic study.

OBJECTIVE: To evaluate the time course of the recovery of atrial mechanical function after pharmacological cardioversion of chronic atrial fibrillation to sinus rhythm. PATIENTS AND METHODS: 21 patients (12 male, 9 female, aged 37-77 years) with chronic atrial fibrillation (< 6 months) were followed up by serial transmitral pulsed Doppler echocardiography. Echocardiographic studies were performed within the first 24 hours and on day 8, 15, and 30 after cardioversion. RESULTS: There was a significant increase (mean (SD)) in the peak A-wave velocity (from 0.35 (0.10) on day 1 to 0.50 (1.73) on day 8, and thereafter a gradual increase to 0.61 (0.14) m/s on day 30). Similarly, integrated late atrial velocities increased from 4.50 (1.46) on day 1 to 5.61 (1.73) on day 8 and 5.97 (1.47) cm/s2 on day 30. The atrial contribution to total transmitral flow increased significantly from 26 (7)% immediately after conversion of atrial fibrillation to sinus rhythm to 34 (7)% on day 30, indicating the haemodynamic benefit of the restoration of sinus rhythm. Left atrial diameter decreased but not significantly, from 4.11 (0.37) to 3.98 (0.34) cm (P < 0.005). CONCLUSIONS: These results suggest that restoration of atrial mechanical function after pharmacological cardioversion in patients with chronic atrial fibrillation is slow and gradual, as it is after electrical DC restoration of sinus rhythm. This time course may have important implications for determining how long treatment with anticoagulants and antiarrhythmic agents needs to continue in individual patients. It will also influence the clinical assessment of the haemodynamic benefit of restoring sinus rhythm in patients with chronic atrial fibrillation.

[The tilt-table test in the diagnosis of vasovagal or neurocardiogenic syncope]. / Uloga tilt-table testa u dijagnozi vazovagalne ili neurokardiogene sinkope.

Syncope is a common clinical problem, and diagnostic evaluation and treatment of the patient with syncope is often a particularly complex task. As many episodes of unexplained syncope are neurocardiogenic or vasovagal, head-up tilt-table testing is a valuable method for identifying individuals with recurrent loss of consciousness. Although over the past several years much has been learned about pathophysiologic mechanism involved, much of the disorder remains incompletely understood. Optimal standardization of head-up titl-table testing protocols is very important for clinical experience exchanges and for comparison of different therapeutic modalities. Medical therapy is often the first choice and a number of pharmacological treatments have been developed. Exceptionally, has to be combined with dual-chamber cardiac pacing. Head-up tilt-table test is a basic diagnostic procedure in the evaluation of the patient with syncope and should be performed in all cardiac and neurophysiologic laboratories.

[Fatal rupture of an echinococcal cyst into the right atrium]. / Smrtonosna ruptura ciste u desni atrij kod bolesnika s ehinokokozom srca.

The case of a man 32 years of age with echinococcosis of the heart who died due to rupture of a pericardial echinococcal cyst into the right atrium with the range into the pulmonary circulation and fatal embolism of the branch of pulmonary artery is presented. Such localization of echinococcus is extremely unusual as well as the complication it caused, and promoted this report which is very instructive for a clinician, the more so that the patient was surgically treated, but irregularly followed up, and the disease had a poor outcome. Prophylaxis with albendazole over a period of one month and more frequent control examinations by means of adequate diagnostic methods in such cases is stressed.

[Family practice and health care of the aged]. / Aktualnost obiteljske medicine u zastiti zdravlja starijih ljudi.

The characteristics of health status of the elderly as well as the assumptions about their future tendencies indicate that primary health care for the elderly is becoming a prominent part of the overall health care. By developing the family practice, elderly people should be provided with different obligatory forms of primary health care--obligatory preventive minimum: health education and guidance, systematic medical examinations, maintenance and development of the existing functional abilities of patients such as treatment, nursing and rehabilitation in patients homes and homes for the elderly, as well as delivery of urgent medical care. The basic principle in health care for the elderly within the primary health care is an active and epidemiologic approach in a certain field, which includes the choice of family physician whose team could provide an integrated comprehensive primary health care which would be at the same time appropriate to the population health needs and also efficient and rational.

[Transesophageal atrial stimulation--a test for myocardial ischemia]. / Transezofagalna atrijska stimulacija--test za ishemiju miokarda.

The aim of the present study was to determine clinical value and the feasibility of transesophageal atrial pacing (TAP) in diagnosing myocardial ischemia in patients with coronary artery disease (CAD). Forty patients with CAD and with significant ST-segment depression in a standard 12-lead ECG during bicycle-stress testing underwent TAP. Rapid atrial stimulation was performed by using a very flexible six-polar polyurethane pacing lead introduced through the nares into the esophagus and connected to the stimulator allowing selection of rate, output voltage and pulse duration. The satisfactory atrial pacing was obtained by 28 +/- 6 V output and 7 +/- 1 ms pulse duration. Of 40 patients who underwent TAP, ischemic ECG changes were induced in 35 (u = 2,24 p < 0,05) and were very similar to those that occurred during bicycle-stress testing according to their intensity and distribution and affected ECG leads with comparable peak rate-pressure products. This suggests comparable sensitivity of TAP and bicycle-stress testing in discovering myocardial ischemia in CAD patients. Four patients had negative test for myocardial ischemia and in one TAP was discontinued because of intolerable chest discomfort. In conclusion, TAP is a reliable alternative technique for the assessment of coronary artery disease. In combination with some other noninvasive methods (echocardiography, scintigraphy, i.v. digital angiography), it has become a routine diagnostic procedure in cardiac patients.

Macro model prediction of elderly people's injury and death in road traffic accidents in Croatia.

The case of elderly people injured and killed in traffic accidents in Croatia is used to illustrate a prediction method. This method consists of several steps. First, the most important variables are selected. Second, to overcome intercorrelation, new variables are constructed that include the old ones. Third, the new variables and its first derivatives are used in a rank correlation method. The results show good predictive capabilities.

[Factors contributing to the onset of heart rupture in acute infarct]. / Faktori koji pridonose nastanku rupture srca u akutnom infarktu.

The aim of this study was to find out the contributing factors for cardiac rupture in the course of acute myocardial infarction (AMI). Past medical histories and autopsy data of 80 patients were analyzed. The first group consisted of 30 patients who died due to heart rupture in the course of AMI and the control group of 50 patients who died from the other, more common complications of AMI. There was no difference between the groups according to age and sex of the patients. All patients who died from the rupture of the heart had a history of heavy chest pain, while it was lacking in 30% of the patients of the control group (p less than 0.01). All the first group patients showed electrocardiograms diagnostic for AMI, while it was lacking in 14% of the second group patients (p less than 0.05). Almost a half of the second group patients (47%) were in the class I of the Killip's classification, while only 20% of the control group did not developed left ventricular failure. Pathological study showed that the rupture of the heart most commonly occurred in the course of an anterior myocardial infarction. There was no difference according to the size of infarctions between observed groups, but the thickness of the left ventricular wall was significantly less (p less than 0.05) in the control group, and the heart weights were higher (p less than 0.05) in the control group. There was advanced atherosclerosis of the coronary arteries and about two thirds of the first group patients showed acute coronary thrombosis.(ABSTRACT TRUNCATED AT 250 WORDS)