Massive gastrointestinal bleeding and obstruction of the ureter caused by the migration of a swallowed toothpick from the sigmoid colon--a case report

In this study, a case of an ingested toothpick partially migrating from the sigmoid colon, causing massive lower gastrointestinal bleeding due to arterial-colic fistula, and stricture of the left ureter is presented. A 70-year-old male was admitted to the emergency department after having feces mixed with fresh and coagulated blood for the past two days. Computed tomography and retrograde ureteropyelography showed the stricture of the left ureter, 1.5 cm below the branching of iliac artery, without any signs of malignancy. Colonoscopy showed fresh blood in the rectum and sigmoid colon up to the neoplasm like granulation tissue mixed with fresh and coagulated blood, which almost obstructed the lumen. Explorative laparotomy showed a foreign body (toothpick) perforating the sigmoid colon through the mesenterial wall, and being stocked with one-third into the left internal iliac artery, causing arterial-colic fistula. The remaining part of the toothpick was surrounded by granulation tissue and chronic inflammatory process, pressing on the distal third of the left ureter. We conclude that a swallowed toothpick may cause a significant gastrointestinal injury with a wide variety of clinical manifestations, and it must be treated with caution. The imaging studies are often inadequate in detecting toothpicks, and thus, we insist on a physical examination, as the best indicator of injury.     

Free energy of membrane protein unfolding derived from single-molecule force measurements

Mechanical single-molecule techniques offer exciting possibilities to investigate protein folding and stability in native environments at submolecular resolution. By applying a free-energy reconstruction procedure developed by Hummer and Szabo, which is based on a statistical theorem introduced by Jarzynski, we determined the unfolding free energy of the membrane proteins bacteriorhodopsin (BR), halorhodopsin, and the sodium-proton antiporter NhaA. The calculated energies ranged from 290.5 kcal/mol for BR to 485.5 kcal/mol for NhaA. For the remarkably stable BR, the equilibrium unfolding free energy was independent of pulling rate and temperature ranging between 18 and 42 degrees C. Our experiments also revealed heterogeneous energetic properties in individual transmembrane helices. In halorhodopsin, the stabilization of a short helical segment yielded a characteristic signature in the energy profile. In NhaA, a pronounced peak was observed at a functionally important site in the protein. Since a large variety of single- and multispan membrane proteins can be tackled in mechanical unfolding experiments, our approach provides a basis for systematically elucidating energetic properties of membrane proteins with the resolution of individual secondary-structure elements.     

Biological bases of dentin hybridization

The aims of this study were threefold: (1) to characterize and quantify the number, diameter and surface area of exposed dentinal tubules on the cross section of the human coronal dentin; (2) to determine if any such differences in these properties arise in relation to the distance from the dentinoenamel junction; and (3) to evaluate whether such differences can influence dentin hybridization. To accomplish these aims, scanning electron microscopy comparative observation was carried out on 60 prepared human premolars, which were divided into three groups of 20 samples each. The three sample groups were cut as follows: (1) in the central fissure region, one millimeter from the enamel-dentine junction; (2) halfway between the enamel-dentine junction and the pulp; and (3) one millimeter from the roof of the pulp chamber. Using one-way analysis of variance (one-way ANOVA) and a regression linear model, the data enumerated below were obtained. First, the mean number of the tubule openings was 19600/mm2 on the first level, 32400/mm2 on the second and 42300/mm2 on the third. The mean tubule diameter on the first level was 0.67 microm, 1.52 microm on the second and 2.58 microm on the third. Finally, exposed tubules on the first level occupied 2.79% of of total dentinal surface area, 23.90% on the second, and 87.78% on the third level. Therefore, significant statistical differences (p < 0.01) between all three groups of the specimens for all three properties were observed, as well as positive correlation between the dentin depth and each of these properties. This indicates that the dentin structural variety, which ultimately determines adhesion to dentine, involves a complex interaction between biological material (dentin) and the particular adhesion system applied.     

The hydrochemical response of small and shallow floodplain water bodies to temporary surface water connections with the main river

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Functional role of the Ca-activated Cl channel DOG1/TMEM16A in gastrointestinal stromal tumor cells

DOG1, a Ca²⁺-activated Cl⁻ channel (CaCC), was identified in 2004 to be robustly expressed in gastrointestinal stromal tumors (GIST). It was rapidly included as a tumor marker in routine diagnostics, but the functional role remained unknown. CaCCs are important regulators of normal physiological functions, but also implicated in tumorigenesis, cancer progression, metastasis, cell migration, apoptosis, proliferation and viability in several malignancies. We therefore investigated whether DOG1 plays a role in the three latter in GIST by utilizing in vitro cell model systems. Confocal microscopy identified different subcellular localizations of DOG1 in imatinib-sensitive and imatinib-resistant cells. Electrophysiological studies confirmed that DOG1-specific pharmacological agents possess potent activating and inhibiting properties. Proliferation assays showed small effects up to 72 h, and flow cytometric analysis of adherent cells with 7-AAD/Annexin V detected no pharmacological effects on viable GIST cells. However, inhibition of DOG1 conveyed pro-apoptotic effects among early apoptotic imatinib-resistant cells. In conclusion, DOG1 generates Cl⁻ currents in GIST that can be regulated pharmacologically, with small effects on cell viability and proliferation in vitro. Inhibition of DOG1 might act pro-apoptotic on some early apoptotic GIST cell populations. Further studies are warranted to fully illuminate the function of DOG1 and its potential as therapeutic target.     

Causal connection of non-specific low back pain and disc degeneration in children with transitional vertebra and/or Spina bifida occulta: role of magnetic resonance--prospective study

The problem of low back pain (LBP) in children is very common and many specialists are dealing with it in everyday practice. The cause for low back pain often is not found and classified under the diagnosis of non specific low back pain. The objective of this prospective study is to determine wether children with non specific low back pain and existence of anomalies in LS spine (transitional vertebra- TV and/or Spina bifida occulta SBO) also have the degeneration of the intervertebral disc (DD) L4-L5 and/or L5-S1. This prospective study included 69 patients from 8 to 16 years of age (X 12.81) of whom 40 were male (57.97%), and 29 female (42.03%). They all were examinated in University of Zagreb, "Sestre milosrdnice" University Hospital Center, Zagreb Children's Hospital, Department of Orthopaedic, Zagreb, Croatia. The reason of their visit was non specific low back pain. Pain was measured by visual analog scale (VAS) and mean score was three, duration of pain was between two and four weeks. Also, pain was sporadic, during daytime and not connected with level of physical activity. They all have undergone an algorithm of radiological examinations. Standard AP and LL radiographs (RTG) were made, as well as magnetic resonance (MR) of LS spine and sacrum in sagittal and transversal plane in T1 and T2 weighted sequence. The anomalies of L5 and S1 were found in 65 patients: transitional vertebra classified according to Castellvi et al. and SBO. In MRI in T2 weighted sequence DD was found in 61 patients which was classified modified from Pearce. Data analysis and comparison showed that 56patients with TV and/or SBO have changes on vertebral dynamic segment L5-S1 (VDS) and that means DD. In 13 patients only DD or spinal anomaly (TV and/or SBO) were found. Correlation between anomalies and DD in those patients was established by McNemar analysis and has shown significant difference (p=0.581) in favour of the patients with anomaly and DD. This has established that all of 56 patients with spinal anomaly could have DD as known cause of LBP.     

Changes in skill and physical fitness following training in talent-identified volleyball players

This study investigated the effect of a skill-based training program on measurements of skill and physical fitness in talent-identified volleyball players. Twenty-six talented junior volleyball players (mean +/- SE age, 15.5 +/- 0.2 years) participated in an 8-week skill-based training program that included 3 skill-based court sessions per week. Skills sessions were designed to develop passing, setting, serving, spiking, and blocking technique and accuracy as well as game tactics and positioning skills. Coaches used a combination of technical and instructional coaching, coupled with skill-based games to facilitate learning. Subjects performed measurements of skill (passing, setting, serving, and spiking technique and accuracy), standard anthropometry (height, standing-reach height, body mass, and sum of 7 skinfolds), lower-body muscular power (vertical jump, spike jump), upper-body muscular power (overhead medicine-ball throw), speed (5- and 10-m sprint), agility (T-test), and maximal aerobic power (multistage fitness test) before and after training. Training induced significant (p < 0.05) improvements in spiking, setting, and passing accuracy and spiking and passing technique. Compared with pretraining, there were significant (p < 0.05) improvements in 5- and 10-m speed and agility. There were no significant differences between pretraining and posttraining for body mass, skinfold thickness, lower-body muscular power, upper-body muscular power, and maximal aerobic power. These findings demonstrate that skill-based volleyball training improves spiking, setting, and passing accuracy and spiking and passing technique, but has little effect on the physiological and anthropometric characteristics of players.     

Are there differences in serum cholesterol and cortisol concentrations between violent and non-violent schizophrenic male suicide attempters?

Previous studies have shown an association between low concentration of serum cholesterol, as well as high concentration of serum cortisol, in suicide behavior. The aim of this study was to evaluate whether men after a violent suicide attempts have different serum cholesterol and cortisol concentrations than those who attempted suicide by non-violent methods. Venous blood samples were collected within 24 hours of admission, to study concentrations of serum cholesterol and cortisol. The sample consisted of 31 male subjects suffering from schizophrenia, admitted in a general hospital after suicide attempt, and was compared with 15 schizophrenic nonsuicidal male controls. Patients with a violent suicidal attempt were found to have significantly lower cholesterol levels and significantly higher cortisol level than patients with non-violent attempts and the control subjects. Our findings suggest that suicide attempts should not be considered a homogenous group. The hypothesis of an association of violent suicidal attempts and peripheral biological markers (cholesterol and cortisol) was supported by our findings.     

Association of stress and delinquency in children and adolescents

The aim of investigation was to assess the impact of subjective stress exposure on delinquent behaviour in children and adolescents. The study included 174 young male delinquents, selected by the method of stratified systematic (random) sample and divided into three age groups of <14, 14-17, and 18-21 years. General data, data on the type of criminal offence, and data on the type of deviant behaviour were collected. A standardised scale of subjective stress was used to allow for comparison of the results obtained in the study with those reported elsewhere. Analysis of variance, chi2-test and factor analysis were used on data processing. A majority of study subjects (55.2%) committed one criminal offence. The criminal offence structure was predominated by proprietary violation (66.7%). Common forms of deviant behaviour included shirking school duties (55.2%), and aggressive behaviour at school (31.0%), in public (29.5%) and in the family (23.6). Parental distrust and punishment (abuse) of the child were identified as the major sources of subjective stress. Youngest subjects significantly differed from other age groups according to their experience of subjective stress described as punishment (abuse) (F = 22.1389, p < 0.001). They were considerably more vulnerable to this type of stress than older age groups. These sources of stress were found to positively correlate with the number of criminal offences committed. Among the sources of stress, parents' distrust of the child significantly correlated with commitment of one criminal offence (F = 2.8618, p < 0.05), and child's punishment (abuse) with a higher number of criminal offences (F = 3.1539, p < 0.05). Criminal activity of children and adolescents is significantly associated with their history of stress exposure over the last two years of life. The higher the stress severity, the greater the rate of delinquency.     

Partial cecal necrosis treated by laparoscopic partial cecal resection

Acute colonic ischemia is the common cause of colitis in elderly population. However, isolated ischemic necrosis of cecum is rare entity, often associated with variety of conditions. Here we present a case of a 73-year old woman with a past history of hypertension presented with clinical symptoms of right lower quadrant abdominal pain and tenderness localized to the right lower quadrant, guarding and rebound tenderness. With diagnosis of acute appendicitis, the patient underwent laparoscopy where the cecal partial necrosis was discovered. Necrotic area of cecum was excised using two endoscopic cutters and laparoscopic appendectomy was performed. Pathologist report showed thrombosis of vessels and necrosis of entire cecal wall. The patient completely recovered without any surgical complications. This is the first case of partial cecum necrosis laparoscopicaly managed and with a partial cecal resection only.