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Aim To determine the value of angles between the left coronary artery main trunk (LMT) and its branches, the anterior interventricular branch (LAD) and the circumflex branch (CX), and their possible relationship with the LMT length. Methods A total of 29 cadaveric hearts were used. The left coronary artery and its branches were dissected. The hearts were then classified according to the number of branches. The LMT length was measured with a digital gauge, and the LAD-CX angle, LMTLAD angle and LMT-CX angle with a manual goniometer. Results The average value of the LMT length was 9.0 mm (6.0-13.5). In 20 (68.97%) samples, the LMT was divided into two terminal branches. There was no statistically significant difference (p=0.321) in LMT length between the hearts with a bifurcation and without it. The average value of the LAD-CX angle was 89.0° (74.5-93.0), with a statistically significant difference (p=0.020) comparing to hearts with trifurcation. The mean value of the LMT-LAD angle was 30.83±9.23° and it was significantly lower (p=0.006) in the group of hearts with bifurcation compared to the group with trifurcation of the main trunk. Conclusion The LMT length shows great variability and is not related to the LAD-CX, LMT-LAD or the LMT-CX angle. Knowledge of the left coronary variation is essential in order to avoid misinterpretation of arteriogram.

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SUMMARY: Microsurgical procedures are the treatment of choice of peripheral nerve injuries, but often fail to reach full functional recovery. Melatonin has neuroprotective actions and might be used as a possible proregenerative pharmacological support. Therefore, the aim of this study was to analyze the time-dependence of the neuroprotective effect of melatonin on the overall fascicular structures of both ends of the transected nerve. Sciatic nerve transection was performed in 34 adult male Wistar rats divided in four groups: two vehicle groups (N=7) treated intraperitoneally for 7 (V7) or 21 (V21) consecutive days with vehicle (5 % ethanol in Ringer solution) and two melatonin groups (N=10) administered intraperitoneally 30 mg/kg of melatonin for 7 (M7) or 21 (M21) consecutive days. At the end of the experiment, proximal stump neuroma and distal stump fibroma were excised and processed for qualitative and quantitative histological analysis. Intrafascicular neural structures were better preserved and the collagen deposition was reduced in the melatonin treated groups than in the vehicle groups. Myelin sheath regeneration observed through its thickness measurement was statistically significantly (p<0,05) more pronounced in the M21 (1,23±0,18 µm) vs. V21 group (0,98±0,13 µm). The mean volume density of the endoneurium was lower in both melatonin treated groups in comparison to the matching vehicle treated groups. Although not statistically different, the endoneural tube diameter was larger in both melatonin groups vs. vehicle groups, and the effect of melatonin was more pronounced after 21 days (24,97 % increase) vs. 7 days of melatonin treatment (18,8 % increase). Melatonin exerts a time-dependent proregenerative effect on nerve fibers in the proximal stump and an anti-scarring effect in both stumps.

Los procedimientos microquirúrgicos son el tratamiento de elección de las lesiones de los nervios periféricos, pero a menudo no logran una recuperación funcional completa. La melatonina tiene acciones neuroprotectoras y podría ser utilizada como un posible apoyo farmacológico proregenerativo. Por lo tanto, el objetivo de este estudio fue analizar la dependencia del tiempo del efecto neuroprotector de la melatonina sobre las estructuras fasciculares generales de ambos extremos del nervio seccionado. La sección del nervio ciático se realizó en 34 ratas Wistar macho adultas divididas en cuatro grupos: dos grupos de vehículo (N=7) tratados por vía intraperitoneal durante 7 (V7) o 21 (V21) días consecutivos con vehículo (5 % de etanol en solución Ringer) y dos grupos grupos de melatonina (N=10) a los que se les administró por vía intraperitoneal 30 mg/kg de melatonina durante 7 (M7) o 21 (M21) días consecutivos. Al final del experimento, se extirparon y procesaron el neuroma del muñón proximal y el fibroma del muñón distal del nervio para un análisis histológico cualitativo y cuantitativo. Las estructuras neurales intrafasciculares se conservaron mejor y el depósito de colágeno se redujo en los grupos tratados con melatonina respecto a los grupos con vehículo. La regeneración de la vaina de mielina observada a través de la medición de su espesor fue estadísticamente significativa (p<0,05) más pronunciada en el grupo M21 (1,23±0,18 µm) vs V21 (0,98±0,13 µm). La densidad de volumen media del endoneuro fue menor en ambos grupos tratados con melatonina en comparación con los grupos tratados con vehículo equivalente. Aunque no fue estadísticamente diferente, el diámetro del tubo endoneural fue mayor en ambos grupos de melatonina frente a los grupos de vehículo, y el efecto de la melatonina fue más pronunciado después de 21 días (aumento del 24,97 %) frente a los 7 días de tratamiento con melatonina (18,8 % de aumento). La melatonina ejerce un efecto proregenerativo dependiente del tiempo sobre las fibras nerviosas del muñón proximal y un efecto anticicatricial en ambos muñones.

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SUMMARY: Myocardial bridges are inborn anomalies frequently found in authopsies. Although tipically clinically silent, they are occasionally associated with severe clinical manifestations, e.g. myocardial ischemia or even sudden death. The pathophysiology and risk factors for these manifestations have not yet been completely elucidated. The connective tissue underneath the bridge has been considered as one of the factors the symptoms depend on. Thus, the aim of this research was to determine the histological characteristics of the connective tissue lying underneath the myocardial bridge and to contribute to a better understanding of the protective effects this passive compartment might have in prevention of severe clinical manifestations of myocardial bridging. The study was carried out on twenty hearts with myocardial bridges. Length of the bridge was determined using a precise electronic caliper. Sections of the myocardial bridges with the underlying connective tissue were obtained and prepared for qualitative and quantitative analysis. The connective tissue underneath the bridges was composed of adipose tissue and loose connective tissue in different ratios. The tissue underneath thin bridges was predominantly composed of adipose tissue, while loose connective tissue was the dominant component under thick bridges. The myocardial bridges had an average thickness of 0,98 ± 0.44 mm and an average length of 15,25±5,65 mm. We found a strong positive correlation between the myocardial bridge thickness and length (r = 0,860, p = 0,0001). The thickness of the passive connective tissue compartment under the myocardial bridges was 0,58±0,22 mm, and there was no correlation between this parameter and the myocardial bridge thickness (r = -0,011; p = 0,963). In the clinical evaluation of patients with these anomalies it is necessary to take into account independently the myocardial bridge thickness and length on one side and the thickness of the connective tissue lying underneath it on the other.

Los puentes miocárdicos son anomalías congénitas que se encuentran con frecuencia en las autopsias. Aunque típicamente éstos son clínicamente silenciosos, ocasionalmente se asocian con manifestaciones clínicas graves, como isquemia miocárdica o incluso muerte súbita. La fisiopatología y los factores de riesgo de estas manifestaciones aún no se han dilucidado por completo. El tejido conectivo debajo del puente se ha considerado como uno de los factores de los que dependen los síntomas. Por lo tanto, el objetivo de esta investigación fue determinar las características histológicas del tejido conectivo que se encuentra debajo del puente miocárdico y contribuir a una mejor comprensión de los efectos protectores que este compartimento pasivo podría tener en la prevención de manifestaciones clínicas graves de puente miocárdico. El estudio se llevó a cabo en veinte corazones con puentes miocárdicos. La longitud del puente se determinó utilizando un calibrador electrónico preciso. Se obtuvieron secciones de los puentes miocárdicos con el tejido conjuntivo subyacente y se prepararon para análisis cualitativo y cuantitativo. El tejido conectivo debajo de los puentes estaba compuesto de tejido adiposo y tejido conectivo laxo en diferentes proporciones. El tejido debajo de los puentes delgados estaba predominantemente compuesto de tejido adiposo, mientras que el tejido conectivo laxo era el componente dominante debajo de los puentes gruesos. Los puentes de miocardio tenían un espesor promedio de 0,98 ± 0,44 mm y una longitud promedio de 15,25 ± 5,65 mm. Encontramos una fuerte correlación positiva entre el grosor y la longitud del puente miocárdico (r = 0,860, p = 0,0001). El grosor del compartimiento de tejido conectivo pasivo debajo de los puentes miocárdicos era de 0,58±0,22 mm, y no hubo correlación entre este parámetro y el grosor del puente miocárdico (r = -0,011; p = 0,963). En la evaluación clínica de pacientes con estas anomalías es necesario tener en consideración de forma independiente el grosor y la longitud del puente de miocardio por un lado y el grosor del tejido conectivo que se encuentra debajo del mismo por el otro.

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Background: Zearalenone is a widely spread mycotoxin, contaminant of most cereal grains. It has uterotropic, estrogenic and anabolic activity in farm animals. The results are hormonal disbalances as hyperestrogenism, Zearalenone inhibits follicle-stimulating hormone production, thus supressing ovarian follicle development and ovulation. Also, it induces oxidative stress. Melatonin acts as a potent natural antioxidant and regulates the reproductive function by modification of steroidogenesis. Objective: The present study was conducted to provide detailed qualitative histological analysis of uterus of female rats treated with zearalenone and melatonin and contribute to better understanding of the topic. Methods: Forty adult, female Wistar rats were equally divided into five groups: Z group - zearalenone, 0,3 mg/kg, i.g.; M group - melatonin, 10 mg/kg, i.p.; ZM group -concomitant application of zearalenone and melatonin in the same dosing regimen, VZ group-zearalenone vehiculum/sunflower oil, i.g. and MZ group-melatonin vehiculum/5% ethanol in Ringer, i.p. Animals were treated daily for 28 consecutive days. After that period, all animals were sacrificed to obtain samples for qualitative histological analysis using the light microscope. Results: Zearalenone led to the alterations of the uterine structures, predominantly in the endometrium that were characterized by metaplasia and hypertrophy of the epithelial cells and hypercellularity of the stroma. In the myometrium, zearalenone induced hypertrophy and hyperplasia of the myocytes. Conclusion: Melatonin, when applied together with zearalenone, blocked the adverse effects of the zearalenone.

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OBJECTIVES: The aim of this study was to investigate the effects of pinealectomy and melatonin treatment on the rat thymus gland characteristics, taking into consideration possible gender differences. MATERIALS AND METHODS: Thirty adult Wistar rats of both sexes were divided into three groups. Group C and group PX served as control groups and included sham-pinealectomized and pinealectomized animals that were treated with 10% ethanol solution (0,1ml/daily, subcutaneous). Animals from third group (group PXM) underwent pinealectomy and seven days after surgery started receiving melatonin dissolved in 10% ethanol solution (3mg/kg/daily, subcutaneous). All animals were treated for 4 weeks. RESULTS: Volume density of the thymus cortex showed statistically significant (p<0,05) decrease while the volume density of the thymus medulla was increased in the pinealectomized compared to the sham-pinealectomized female rats. Numerical density of macrophages as well as the distribution of blood vessels showed no gender differences. The numerical density of lymphocytes was statistically significantly decreased in female in comparison to the male pinealectomized rats. Melatonin treatment was proved to cause reverse effects in the sense that the results from the melatonin treated group corresponded to the results obtained from the control group of animals. CONCLUSION: The results of this study suggest that the pinealectomy causes gender-related changes in the rat thymus. Short-term melatonin treatment showed reverse effect, equally in both sexes.

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The aim of this research was to assess the reactive changes of rat proximal tubules caused by gentamicin and the effect of relatively low doses of melatonin. 48 adult male Wistar rats were distributed into six groups of equal size which all received one of the following daily intraperitoneal injections: vehicle (5% ethanol in Ringer solution) during 11 days (C); gentamicin (80 mg/kg) during 8 days (G), two groups which concomitantly received gentamicin (80 mg/kg) during 8 days and melatonin in two different test doses (5 or 20 mg/kg) during 11 days (GM1, GM2) and two groups treated only with melatonin in two different doses (5 or 20 mg/kg) during 11 days (M1, M2). Histological analysis included qualitative and semi-quantitative light microscopy analysis of proximal tubules. Exogenous melatonin had no significant effect on the microstructure, independently of dosis. The changes of proximal tubules microstructure induced by gentamicin were expressed in the form of granulovacuolar degeneration, necrosis and desquamation. The grade of proximal tubular changes was smaller in animals who besides gentamicin received melatonin. Melatonin has a dose dependent protective effect on the structural alterations of proximal tubules of the kidney induced by gentamicin.

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The advent of multicellular organisms was accompanied by the development of short- and long-range chemical signalling systems, including those provided by the nervous and endocrine systems. In turn, the cells of these two systems have developed mechanisms for interacting with both adjacent and distant cells. With evolution, such mechanisms have diversified to become integrated in a complex regulatory network, whereby individual endocrine and neuro-endocrine cells sense the state of activity of their neighbors and, accordingly, regulate their own level of functioning. A consistent feature of this network is the expression of connexin-made channels between the (neuro)hormone-producing cells of all endocrine glands and secretory regions of the central nervous system so far investigated in vertebrates. This review summarizes the distribution of connexins in the mammalian (neuro)endocrine systems, and what we know about the participation of these proteins on hormone secretion, the life of the producing cells, and the action of (neuro)hormones on specific targets. The data gathered since the last reviews on the topic are summarized, with particular emphasis on the roles of Cx36 in the function of the insulin-producing beta cells of the endocrine pancreas, and of Cx40 in that of the renin-producing juxta-glomerular epithelioid cells of the kidney cortex. This article is part of a Special Issue entitled: The Communicating junctions, composition, structure and characteristics.

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Congenital anomalies of the urinary system are relatively common anomalies. In Bosnia and Herzegovina there is no existent unique evidence of congenital anomalies and registries. The aim of this study was to obtain the frequency of different urinary tract anomalies types and their sex distribution among cases hospitalized in the Department of Pediatric Surgery of the University of Sarajevo Clinics Centre, Bosnia and Herzegovina, during the period from January 2002 to December 2006. Retrospective study was carried out on the basis of clinical records. Standard methods of descriptive statistics were performed for the data analysis. Among 289 patients that were surgically treated 62,37% of the patients were male patients, while 37,63% were female patients. Twenty nine different urinary system anomalies types were found in this study. These were: vesicoureteral reflux (99 cases or 30,75%), hypospadias (62 cases or 19,26%), pelviureteric junction obstruction (42 cases or 13,04%), megaureter (35 cases or 10,87%), duplex pelvis and ureter (16 cases or 4,97%), bladder diverticulum (8 cases or 2,48%), ureterocoele (7 cases or 2,17%), stenosis of the external urethral opening (6 cases or 1,86%), ectopic kidney, duplex kidney and pelvis (each 5 cases or 1,55%), polycystic kidneys and urethral stricture (each 4 cases or 1,24%), multicystic kidney (3 cases or 0,93%), kidney agenesis, ureter agenesis, urethral diverticulum, ectopic ureter, horseshoe kidney and fetal kidney (each 2 cases or 0,62%), renal aplasia, urethral atresia, renal cyst, urachal cyst, epispadias, bladder exstrophy, renal hypoplasia, renal malrotation and Prune-Belly syndrome (each 1 case or 0,31%). According to this study, urinary tract anomalies were more common in male than in female patients (62,37%). Generally, the most frequent anomaly type was vesicoureteral reflux in total number of 99 cases, and in females (66 cases), but hypospadias was the most common anomaly in males (62 cases). The anomalies of other systems associated with urinary system anomalies were found in ten cases. These were: cryptorchidism, congenital inguinal hernia, open inner inguinal ring, uterus bicornis unicollis and one case of multiple anomalies.

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