Medicina, Volume 46, Issue 1 (January 2010) – 11 articles

Human diseases involving protein misfolding and aggregation have received increasing attention in recent years. Alzheimer’s disease and other diseases associated with aging are sweeping the developed countries whose populations are rapidly aging. Recent progress has improved our knowledge about molecular and cellular pathogenesis of these diseases. For more than 20 years, multiple diseases such as Alzheimer’s and Parkinson’s diseases have been associated with accumulation of abnormal protein fibrils. These self-assembling fibrils, referred as “amyloid,” have been considered the pathogenic molecules that cause cellular degeneration. Accumulation of fibrillar Aβ in plaques underlies the theory for Alzheimer’s disease. Recent experiments have provided evidence that fibrils are not the only neurotoxins. Soluble oligomers and protofibrils play a crucial role in causing cellular dysfunction and death. These oligomers, the missing links in the original amyloid cascade hypothesis, have been incorporated into an updated amyloid cascade. Despite new information gained, there is no disease-modifying treatment. New insights into disease mechanisms and new therapeutic strategies give hope for change. Full article

The aim of this study was to compare the prevalence of the metabolic syndrome diagnosed using three different definitions and to evaluate its associations with ischemic heart disease in Kaunas adult population.
Material and methods. Data of preventive screening carried out in Kaunas in 2001–2002 according to the MONICA study protocol were used for analysis; a total of 1336 persons aged 35–64 years (603 men and 733 women) were recruited. The metabolic syndrome was defined by the World Health Organization, Adult Treatment Panel III, and International Diabetes Federation definitions. Ischemic heart disease was diagnosed based on the following criteria: a documented history of myocardial infarction, angina pectoris, or ischemic changes on electrocardiogram.
Results. The metabolic syndrome was identified for 11.3% of men and for 9.4% of women using the World Health Organization definition, for 19.4% of men and for 26.3% of women using the Adult Treatment Panel III definition, and for 30.0% of men and for 37.7% of women using the International Diabetes Federation definition. In male and female groups, the prevalence of the metabolic syndrome (irrespective of definition) significantly increased with age (P<0.05). After adjusting for age, men diagnosed with the metabolic syndrome using the International Diabetes Federation definition (OR=2.30; P=0.001) and Adult Treatment Panel III definition (OR=1.97; P=0.01) and women diagnosed with metabolic syndrome using the International Diabetes Federation definition (OR=1.50; P=0.039) had a significantly higher risk of having ischemic heart disease as compared with those without the metabolic syndrome by the same definitions. The metabolic syndrome diagnosed using the World Health Organization definition was not associated with a significant risk of ischemic heart disease in men and women.
Conclusion. In Kaunas population aged 35–64 years, the highest prevalence of the metabolic syndrome was determined according to the International Diabetes Federation definition. Usage of the International Diabetes Federation and the Adult Treatment Panel III definitions in establishing diagnosis of the metabolic syndrome provides more opportunities to identify subjects with ischemic heart disease. Full article

Foreign languages are becoming an essential prerequisite for a successful carrier among all professions including public health professionals in many countries. The expanding role of English as a mode of communication allows for university graduates to project and to seek their career in English-speaking countries. The present study was carried out in the framework of EU Leonardo da Vinci project “Specialist English as a foreign language for European public health.” The study aimed to get a deeper insight how the English language is perceived as a foreign language, by Polish and Lithuanian public health students, what is level of their language competence, which level of English proficiency they expect to use in future.
Material and methods. A total of 246 respondents completed the special questionnaires in autumn semester in 2005. A questionnaire form was developed by the international project team. For evaluation of English competences, the Language Passport (Common European Framework of Reference for Languages of Council of Europe) was applied.
Results. Current self-rated proficiency of the English language was at the same level for Lithuanian (3.47±1.14) and Polish (3.31±0.83) respondents (P>0.05). Majority of respondents (88.6% of Lithuanian and 87.8% of Polish) reported using the English language for their current studies. Respondents reported a significant increase in necessity for higher level of English proficiency in future: mean scores provided by respondents changed from B1 level to B2 level. Respondents gave priority to less formal and practice-based interactive English teaching methods (going abroad, contacts with native speakers) in comparison with theory-oriented methods of learning (self-studying, Internet courses).
Conclusions. Similar levels of English language in all five areas of language skills were established in Polish and Lithuanian university students. Respondents gave more priorities to less formal and practice-based interactive English teaching methods (going abroad, contacts with native speakers) in comparison with theory-oriented or classroom-based methods of learning (self-studying, Internet courses). Survey showed a growing interest of students in improving English language in the future in Poland and Lithuania. Full article

Objective. There are well-documented reports of cisplatin-associated hyponatremia in the literature, but there are no data on gender-dependent differences. The aim of the present study was to define characteristics of 24-hour urinary sodium excretion in young adult Wistar rats of both genders and to evaluate the gender-related effect of cisplatin.
Materials and methods. Twelve control Wistar rats (6 males and 6 females) and 12 cisplatintreated Wistar rats (6 males and 6 females) after a single and repeated injection of cisplatin (once a day for 3 days) at a dose of 2.5 mg/kg body weight into the caudal vein were examined. The experiment was carried out by measuring 24-h urinary sodium, potassium, chloride, magnesium, creatinine excretion and pH in the urine of age-matched male and female rats.
Results. The 24-h urinary sodium excretion, sodium/chloride ratio, and diuresis showed no gender-related differences in control rats. After a single administration of 2.5 mg/kg cisplatin, 24-h urinary sodium excretion was not significantly higher in cisplatin-treated rats than in gender-matched controls. After repeated cisplatin administration, 24-h urinary sodium excretion was significantly higher in cisplatin-treated male rats as compared to matched controls (P<0.05). No such effect was found in cisplatin-treated female rats.
Conclusion. The study data show that cisplatin enhances urinary sodium excretion in male but not in female rats. The mechanism of such a gender-related effect is not yet clear. Further investigations are necessary to elucidate the mechanism of this pharmacological effect of cisplatin. Full article

This study investigated possible implication of nitric oxide and prostanoids in anaphylactic reaction in small mesenteric and coronary arteries.
Material and methods. Isolated arteries from guinea pigs, sensitized with 0.5 mL of horse serum or sham-sensitized, were challenged with 1% of horse serum in vitro. Contractile responses of arteries (normalized diameter, 350–450 μm) were recorded by a small blood vessel wire myograph. For inhibition of the release of NO or prostanoids, vessels were pretreated with N(G)-nitro-L-arginine methyl ester (30 μM) or indomethacin (10 μM), respectively.
Results. Antigen challenge was followed by contraction of both coronary and mesenteric vessels. Two patterns of contraction were observed: 1) peak contraction – an immediate transient contraction of relatively high amplitude; this was the most common pattern; 2) biphasic: the initial peak contraction was followed by a slow growing contraction with low amplitude. Biphasic pattern was observed in 60% of the mesenteric vessels and 40% of the coronary vessels. Inhibition of NO synthase significantly increased the peak contraction in the coronary vessels and the second-phase contraction in the mesenteric vessels. Inhibition of cyclooxygenase caused a decrease in the peak and second-phase contraction of both the coronary and mesenteric vessels.
Conclusions. Despite anaphylactic contraction, nitric oxide seems to be released from the endothelium following antigen challenge in the small coronary and mesenteric arteries. This may contribute to the development of hypotension during anaphylaxis. Prostanoids are playing a different role – the contracting products of cyclooxygenase pathway are important for the development of anaphylactic contraction of the small isolated arteries. Full article

Nasal tip and septal perforations may lead to significant upper airway problems as well as disturbing esthetic changes in the external contour of the nose. Nasal defects impede normal social contact and create great self-identity problems for the patients.
We report the case of a 37-year-old woman, taking drugs for 10 years, who had sepsis and nasal abscess with necrosis of the nasal tip and septum. Using a composite expanded forehead flap for reconstruction of the nose, good esthetic and functional results were achieved. Full article

Vancomycin is widely used against methicillin-resistant Staphylococcus aureus infections, but it is associated with many adverse effects such as nephrotoxicity, ototoxicity, gastrointestinal disturbances, blood disorders, and two types of hypersensitivity reactions – an anaphylactoid reaction known as “red man syndrome” and anaphylaxis. We report a case of a 23-year-old man who developed a vancomycin-induced anaphylactic reaction in the treatment of methicillin-resistant Staphylococcus aureus infection. Full article

Objective. The aim of this prospective study was to establish the influence of operative parameters on outcomes after transurethral resection of the prostate.
Materials and methods. In this prospective case series study, 89 patients underwent transurethral resection of the prostate. The standardized protocol was used to investigate the impact of operative parameters (resected tissue weight, residual prostate weight, and residual prostatic weight ratio [total prostate volume – resected tissue weight / total prostate volume]) on outcomes after six months following transurethral resection of the prostate. The evaluation of treatment efficacy was done using the criteria of the Second International Consultation on Benign Prostatic Hyperplasia. All postoperative results were categorized as excellent, good, fair, or none. Treatment was considered effective when the postoperative results were excellent and good, and ineffective when results were fair and none.
Results. Treatment was effective for 85.4% and ineffective for 14.6% of the patients. The univariate analysis of operative parameters detected the residual prostatic weight ratio (cutoff value, 0.71; P<0.001; sensitivity, 0.62; specificity, 0.96; OR, 39.47) as the strongest independent predictor of ineffective outcome. Logistic regression analysis revealed two important parameters of unfavorable outcomes: residual prostatic weight ratio (cutoff value, 0.71; P<0.001; OR, 62.16) and residual prostate weight (cutoff value, 26.6 mL; P=0.013; OR, 9.98). When the values of both these parameters were lower than their cutoff values, the probability of an ineffective outcome was reduced to 3%; however, when they were higher, the probability of an unfavorable outcome was increased to 95%.
Conclusions. Residual prostatic weight ratio and residual prostatic weight are significant operative parameters for the prediction of outcomes after transurethral resection of the prostate. Full article

Įvadas. Kojų giliųjų venų trombozė yra sveikatos apsaugos ir socialinė problema. Giliųjų venų trombozė pasireiškia 20–30 proc. ligonių po atvirų pilvo chirurgijos operacijų bei 5–6 proc. ligonių po laparoskopinių pilvo ertmės operacijų. Šio tyrimo tikslas – įvertinti ir palyginti mažos molekulinės masės heparinų (MMMH) ir kintamos pneumokompresijos kojinių galimą hipokoaguliacinį poveikį laparoskopinių fundoplikacijų metu.
Tirtųjų kontingentas ir tyrimo metodai. Atlikta atsitiktinių imčių klinikinė studija. Tiriamieji suskirstyti į dvi grupes: pirmos grupės ligoniams laparoskopinės fundoplikacijos metu buvo naudojamos kintamos pneumokompresijos kojinės; antros grupės ligoniams – kintamos pneumokompresijos kojinės operacijos metu plius MMMH, kuris sušvirkštas į poodį 1 val. prieš operaciją. Plazmos protrombino fragmentas F1+2 (F1+2), trombino-antitrombino kompleksas (TAT) – trombogenezės žymenys bei laisvas plazmos audinių kelio faktoriaus inhibitorius (fTFPI) – hipokoaguliacijos žymuo buvo tiriami 1 val. prieš operaciją, operacijos metu ir baigus operaciją.
Tyrimo rezultatai. Pirmoje grupėje F1+2 ir TAT koncentracija kraujo plazmoje statistiškai reikšmingai padidėjo operacijos metu bei ją baigus. Antroje grupėje F1+2 ir TAT koncentracija operacijos metu nekito. fTFPI koncentracija kraujo plazmoje statistiškai reikšmingai padidėjo operacijos metu antroje grupėje, o pirmoje grupėje ji nekito.
Išvada. MMMH ir kintamos pneumokompresijos kojinės derinys, vartojamas laparoskopinių fundoplikacijų metu, sukėlė hipokoaguliacinį poveikį, kurio nepastebėta naudojant tik kintamas pneumokompresines kojines. Full article

Majority of patients suffering from liver tumors are not candidates for surgery. Currently, minimal invasive techniques have become available for local destruction of hepatic tumors. Radiofrequency ablation is based on biological response to tissue hyperthermia. The aim of this article is to review available biological data on tissue destruction mechanisms. Experimental evidence shows that tissue injury following thermal ablation occurs in two distinct phases. The initial phase is direct injury, which is determined by energy applied, tumor biology, and tumor microenvironment. The temperature varies along the ablation zone and this is reflected by different morphological changes in affected tissues. The local hyperthermia alters metabolism, exacerbates tissue hypoxia, and increases thermosensitivity. The second phase – indirect injury – is observed after the cessation of heat stimulus. This phase represents a balance of several promoting and inhibiting mechanisms, such as induction of apoptosis, heat shock proteins, Kupffer cell activation, stimulation of the immune response, release of cytokines, and ischemia-reperfusion injury. A deeper understanding of the underlying mechanisms may possibly lead to refinements in radiofrequency ablation technology, resulting in advanced local tumor control and prolonged overall survival. Full article

Gap junction channels are composed of two apposing hemichannels (connexons) in the contiguous cells and provide a direct pathway for electrical and metabolic signaling between adjacent cells. The family of connexin genes comprises 20 members in the mouse and 21 genes in the human genome. Connexins are expressed in all tissues except differentiated skeletal muscle, erythrocytes, and mature sperm cells. Various tissues express more than one type of connexins; therefore, homotypic, heterotypic, and heteromeric gap junction channels may form between cells. In this article, we briefly review basic gating and permeability properties of homotypic and heterotypic gap junction channels as well as recent achievements in the research of their regulation by transjunctional voltage, intracellular calcium, pH, and phosphorylation. Full article