Miljenko Kovačević

The transition from pulpitis to periapical periodontitis in dogs' teeth.

The purpose of the study was to histologically analyse transition from pulpitis to periapical periodontitis on dogs teeth. Pulps of mandibular premolars (37 roots) were exposed using a low-speed handpiece. Teeth were left open to the oral environment for 20, 35, 50 and 65 days. After the experimental period animals were sacrificed. Undemineralised teeth with surrounding bone, embedded in methylmetacrylate, were prepared for standard histological analysis. All teeth with pulpitis (five roots), regardless of the experimental period, had acute serose periapical periodontitis. All teeth (15 roots) with partial pulp necrosis had subacute periapical periodontitis. Teeth with complete pulp necrosis (19 roots) had chronic periapical periodontitis and in one case suppurative apical periodontitis. The condition of the pulp correlates with the histopathological findings of periapical tissue in the open types of pulp infection. Acute periapical periodontitis begins during pulpitis and can occur before 20 days of pulp exposure in the dog.

Apoptosis and cardiopulmonary bypass.

Abstract  Aim: The aim of this study was to ascertain the percentage of apoptotic myocites in patients who underwent coronary artery bypass surgery. Apoptotic index (AI) obtained with in situ terminal deoxynucleotidyl transferase‐labeled dUTP nick end labeling (TUNEL) method and Bak protein expression were compared. Patients and Methods: Twenty consecutive patients who underwent coronary artery bypass surgery, myocardial samples from the right atrium were taken in three stages: before cannulation (the first sample group), after declamping (the second sample group), and 20 minutes after reperfusion (the third sample group). The percentage of apoptotic cells was determined by TUNEL method. Expression of Bak protein was immunohistochemically analyzed. Intermittent ischemia and moderate hypothermia were used as methods of myocardial management during surgery. A statistical analysis was performed by using the Friedman ANOVA analysis of variances, the Kendall coefficient of concordance and the Wilcoxon matched pair test. Results: In the first sample group mean value of Bak expression was 2.61 ± 2.18, compared with AI 5.38 ± 3.58, after declamping (the second sample group) the mean value of Bak expression was 4.31 ± 2.68 while AI was 7.63 ± 4.38 and after 20 minutes of reperfusion in the third sample group mean value of Bak expression was 8.89 ± 4.45, while AI was 15.6 ± 8.45. When compared by using Wilcoxon matched pair test two methods significantly correlated, p > 0.0001. Conclusion: The positive correlation between AI obtained by TUNEL method and expression of Bak protein may suggest that apoptosis is activated mainly through mitochondrial activation pathway in ischemic reperfusion injury. The results suggest that ischemic reperfusion injury increases the AI in the right atrial tissue. If so, immunohistochemical expression of Bak protein could be used as a marker of myocardial ischemia induced injury.

Vomiting as a reliable sign of concussion

Concussion is the most common type of traumatic brain injury, with headache being the most frequent symptom of mild traumatic brain injury (MTBI) (including dizziness, vomiting, nausea, lack of motor coordination or difficulty balancing). Concussion may be caused by a blow to the head, or by acceleration forces without a direct impact. Often, MTBI occurs as the result of a sports injury. Loss of consciousness is always present, unlike vomiting. Therefore, we hypothesize vomiting to be considered as a cardinal sign of concussion. Stimulation of vomiting centres finally triggers vomiting. Professional boxers and mixed martial arts competitions reluctantly agree with stringent rules and protective clothing. We discuss the issue of further protection for those engaged in these and other sports.

Intra-abdominal migration of a Kirschner wire

A 87-year-old male was admitted with dislocation of bone fragments after osteosynthesis of a pertrochanteric fracture using a condylar plate and Kirschner wire. Radiographic examinations revealed secondary dislocation of bone fragments of the operated hip and migration of the Kirschner wire through the acetabulum roof into the peritoneal cavity (Fig. 1). A surgical procedure was performed through the anterolateral Watson – Jones approach to the hip joint, and the condylar plate, the femoral head, and the neck were extracted. Th e Kirschner wire was not reachable through the opening on the acetabular roof (Fig. 2). During the surgery the patient developed cardiac instability and the procedure was fi nished immediately. Th ree days later his cardiac condition was stable and we scheduled the laparotomy. Kirschner wire was found among small intestine loops and extracted (Fig. 3). Postoperative course was unremarkable, and 14 days after the laparotomy the patient was discharged from the hospital. Migration of fi xation devices, and especially Kirschner wires is a wellrecognized complication of osteosynthesis surgery [1–3]. Hrvoje Štalekar, Karmen Lončarek, Miljenko Kovačević Confl ict of interest Th e authors declare no confl ict of interest.

Apoptotic cell death and rupture of abdominal aortic aneurysm.

The abdominal aortic aneurysm (AAA) development and expansion is characterized by an extracellular matrix degradation and widespread inflammation. In contrast, the processes that characterize the AAA rupture are not completely understood. The results obtained in animal and clinical studies have shown the importance of inflammation, proteolysis, and antioxidant mechanisms in the aortic degeneration and formation of AAA. We hypothesize that the rupture of the AAA could have a similar pathway like an atherosclerotic plaque rupture, and in both the cases the apoptotic cell death of smooth muscle cells could play a significant role. If the apoptotic cell death significantly contributes to the expansion and rupture of aneurysm, the hypothesis is that aggressive medical antiapoptotic treatment with high doses of appropriate drugs could decrease the apoptotic index of smooth muscle cells, reduce the aneurysm expansion and prevent rupture.

Crosstalk Between Enzyme Matrix Metalloproteinases 2 and 9 and Regulatory T Cell Immunity in the Global Burden of Atherosclerosis.

Changes in immune and inflammatory responses may play a crucial role in the development and progression of atherosclerosis, as an autoimmune, chronic and progressive inflammatory disease. Immunological activity and vascular inflammation during atherosclerosis can be modulated by autoimmune responses against self‐antigens, according to changeable risk factors (cholesterol, oxidized low‐density lipoprotein (ox‐LDL) in the vascular wall, fatty acids, etc.), and accompanied by accumulation of leucocytes and proinflammatory cytokines, which stimulate the transcription of matrix metalloproteinases (MMPs), whose concentration are increased in foam cell‐rich regions. Regulatory T cells (Tregs) represent a unique subpopulation of T cells specialized in the regulation of immune response and in the suppression of proatherogenic T cells. The aim of our study was to examine the interactions between the concentration of enzyme matrix metalloproteinases 2 and 9 (MMP‐2 and 9) in urine and the percentage of Tregs in peripheral blood of two groups of patients: with carotid artery stenosis (CAS), undergoing surgery and with mild atherosclerosis (A) from general practice. The method of enzyme immunoassay (ELISA) was used to determine enzyme MMP expression, and Tregs was examined by flow cytometric analysis. Our data have showed a large increase in the enzyme MMP‐2 and 9 in the urine of CAS and A patients in comparison with healthy controls and indicated this method as an easy marker for the monitoring of the development of atherosclerosis. Simultaneously, the diminished number of Tregs in the same patients pointed the importance of these regulatory mechanisms in the etiopathogenesis of atherosclerosis and possible Tregs‐mediated therapy.

Predicting Carotid Restenosis by Comparison of Plaque MCP-1 mRNA Expression and Serum Levels

As cardiovascular pathology grows in numbers, research into the discovery of new chemokine biomarkers should not be neglected, as they seem to be paramount in atherosclerosis prevention and its early detection. Chemokines attract and activate leukocytes and are well recognized in the environment of inflammatory response. MCP-1 is a valuable chemokine whose potential to become a new crucial atherosclerosis marker is surely worth investigating. Since quantities of MCP-1 found in lesions are as low as immeasurable, we propose the use of an immunohistochemical method for the quantification of MCP-1 levels in atherosclerotic lesions. Additionally, serum levels of MCP-1 can be measured by commercially available immunoassays. Proposed MCP-1 concentration increase may explain the acceleration in lesions atherosclerosis progression as chemokine activation occurs once they bind to specific ligands. If proven, this hypothesis would indicate the need for further studies in order to objectively link the increased MCP-1 expression with carotid restenosis.

Endovascular Management of Superior Mesenteric Artery (SMA) Aneurysm – Adequate Access is Essential for Success – Case Report

Summary Background An aneurysm of the superior mesenteric artery (SMA) with a diameter of 2.2 cm was found incidentally on an ultrasound (US) examination in a 26-year-old woman. The only known risk factor was an intracranial aneurysm that was found on her grandmother’s autopsy. Based on pregnancy planning and the current literature, endovascular management with a covered stent was proposed. Case Report Self-expandable, covered stent (Bard, Fluency®) was implanted using a single transfemoral approach. A stiff guidewire and a large sheath distorted the anatomy, which resulted in an incomplete aneurysmal neck covering. In the absence of additional covered stents, the procedure was terminated. Two weeks later, computed tomographic angiography (CTA) confirmed persistent aneurysmal perfusion due to the incomplete neck coverage. A multidisciplinary board opted for a second endovascular attempt, this time with a longer covered stent via the transaxillary approach in order to reduce anatomical distortion. Balloon, expandable, cobalt-chrome covered stent (Jotec, E-ventus BX®) was implanted in the SMA, covering the aneurysmal neck and overlapping the previously implanted covered stent. Angiography confirmed a complete exclusion of the aneurysm. A control US performed three weeks later confirmed a patent covered stent and complete aneurysmal exclusion. There was a mild median nerve damage periprocedurally that resolved in three months. The most recent US control examination, performed eleven months after the procedure, showed an excluded aneurysm and a patent covered stent. There were no clinical signs of bowel ischaemia during the follow-up period. Conclusions Endovascular management of SMAA proved to be safe and efficient. The “access from above” is probably safer and should be considered in the majority of cases with acceptable sizes of access vessels. Mid-term results in our patient are good and life-long follow-up is planned to prevent late complications.

Traumatic avulsion of left common carotid and vertebral artery

The traumatic avulsion of the left common carotid and vertebral artery is a rare condition and surgeons have limited experience with this type of injury. We have presented the case of a 31-year-old female who has suffered a car accident, with penetrating wounds on the left side of the neck and thorax.