Adsorption-desorption processes on discrete substrates-optimization of monolayer growth

Kinetics of the deposition process of dimers on a 1D lattice in the presence of desorption is studied by Monte Carlo method. The growth of the coverage θ(t) above the jamming limit to its steady-state value θ∞ is analyzed when desorption probability Pdes decreases both stepwise and linearly (continuously) over a certain time domain. We report a numerical evidence that the process of vibratory compaction of granular materials can be optimized by using a time dependent intensity of external excitations

Numerical study of anisotropic irreversible deposition of extended objects on a triangular lattice

The properties of the anisotropic random sequential adsorption (RSA) of objects of various shapes on a two-dimensional triangular lattice are studied numerically by means of Monte Carlo simulations. The depositing objects are formed by self-avoiding lattice steps. Anisotropy is introduced by positing unequal probabilities for orientation of depositing objects along different directions of the lattice. This probability is equa

Kinetics of the Bray-Liebhafsky oscillatory reaction perturbed by polymer supported cobalt catalyst

The Bray-Liebhafsky (BL) oscillatory reaction generated in the batch reactor at 62- 68 oC was perturbed by cobalt(II)-nitrate, supported on the macroreticular copolymer of poly-4-vinylpyridine with divinylbenzene (Co-PVPDVB). The kinetic data was analyzed of the complex pathways of the hydrogen peroxide decomposition in the examined BL reaction. The obtained results confirm that the kinetics of the BL reaction in the presence Co-PVPDVB comes partially from the Co-catalyst and partially from the macroreticular copolymer support.Oscilatorna reakcija Bray-Liebhafsky (BL) realizovana u zatvorenom reaktoru na temperaturi 62-68 oC je perturbovana sa kobalt(II)nitratom ugrađenim na makroretikularnom kopolimeru poli-4-vinilpiridina sa divinilbenzenom (Co- PVPDVB). Analizirani su kinetički podaci kompleksnih reakcionih puteva razlaganja vodonikperoksida u ispitivanoj BL reakciji. Dobijeni rezultati potvrđuju da je u prisustvu Co-PVPDVB kinetika BL reakcije delimično određena Co-katalizatorom, a delimično makromolekularnim kopolimernim nosačem katalizatora

Značaj patohistološkog nalaza i ekspresije Bcl-2 za prognozu i lečenje oralnog planocelularnog karcinoma

Background/Aim. Numerous studies were aimed to detect and characterize various tumor markers in patients with oral planocellular carcinoma in order to reduce moratlity and mobidity rates of these patients, as well as to establish the correlation between the expression of specific tumor marker and prognostic outcome. The aim of this study was to determine patohistological characteristics of tumor and peritumor tissue in patients with oral planocellular carcinoma, with special regard to the expression of Bcl-2, as well as to point out the significance of clinicomorphological correlations for clinical use. Methods. Sixty-two patients with oral planocellular carcinoma, stage II and III, were examined. The patients were surgically treated for this condition at the Clinic for Maxillofacial Surgery, Military Medical Academy, Belgrade. Surgical specimens were obtained from both tumor and peritumoral tissues. Patohistologic degree of tumor differentiation and the immunohistochemical expression of Bcl-2 were determinated for each specimens. Results. Twenty-four (39%) patients had tumor dimension T1, while six (9%) and thirty-two (52%) patients had tumor dimension T2 and T3, respectively. Patohistologic analysis of peritumor connective, fat, muscle and bone tissue samples confirmed the presence of tumor infiltration. The expression of Bcl-2 in peritumor tissue samples correlated significantly with tumor's histologic grade (ς = 0.468; p lt 0.001), nuclear grade (ς = 0.430; p lt 0.001) and nucleocytoplasmic ratio (ς = 0.410; p = 0.001). Conclusion. This results suggest that the expression of Bcl-2 in combination with patohistologic findings could have a prognostic value in patients with oral planocellular carcinoma.Uvod/Cilj. Mnogobrojna istraživanja usmerena su na detekciju i karakterizaciju različitih tumorskih markera kod oralnog planocelularnog karcinoma sa ciljem da se smanji morbiditet i mortalitet, kao i uspostavi korelacija između stepena ekspresije određenog markera i prognoze bolesti. Cilj ovog rada bio je da se utvrde patohistološke karakteristike tumorskog i peritumorskog tkiva bolesnika sa oralnim planocelularnik karcinomom, posebno stepen ekspresije markera Bcl-2, da se ukaže na značaj korelacije kliničkomorfoloških parametara, kao i na mogućnost primene ovih rezultata u kliničkoj praksi. Metode. Studija je obuhvatila 62 bolesnika u II i III stadijumu oralnog planocelularnog karcinoma, operisana u Klinici za maksiofacijalnu hirurgiju Vojnomedicinske akademije u Beogradu. Kod svih bolesnika određivani su stadijum bolesti, patohistološki stepen diferentovanosti tumora, a imunohistohemijskom metodom praćena je ekspresija markera Bcl-2 u peritumorskom tkivu. Rezultati. U analiziranoj grupi bila su 24 (39%) bolesnika sa tumorom veličine T1, 6 (9%) bolesnika sa tumorom veličine T2, a 32 (52%) bolesnika sa primarnim tumorom veličine T3. Infiltracija tumora u peritumorskom tkivu verifikovana je patohistološkom analizom okolnog vezivnog, masnog, mišićnog tkiva i kosti, koji su bili zahvaćeni resekcijom. Utvrđena je statistički visokoznačajna pozitivna korelacija između stepena ekspresije proteina Bcl-2 u peritumorskom tkivu, sa jedne strane, i histološkog gradusa tumora (ς=0,468; p lt 0,001), nukleusnog gradusa tumora (ς=0,430; p lt 0,001) i nukleocitoplazmatskog odnosa u tumorskim ćelijama (ς=0,410; p = 0,001). Zaključak. Ekspresija Bcl-2 u kombinaciji sa patohistološkim parametrima može biti značajan prognostički faktor, pa mu treba posvetiti više pažnje u okviru multidisciplinarnog istraživanja prognoze oralnog planocelularnog karcinoma

Non-Hodgkin lymphomas of oral cavity

Non-Hodgkin lymphomas (NHL) often show up in an extranodal pattern, especially in the head and neck. Intraoral locations are much less frequent, particularly when they are single. This, in turn, can lead to a prolonged diagnosis and even to inadequate treatment. Different patients with initial extranodal location of NHL which were not previously diagnosed and in which it was manifested only intraoraly are presented in this paper. These cases are presented together with the additional examinations used for the early diagnosis and with the corresponding clinical pictures, as well as with the overview of other cases from the available literature

Bisphosphonate related osteonecrosis of the maxilla: A case report

Introduction. Bisphosphonates are a group of medications which have an important role in the treatment of some bone diseases. Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a side effect of intravenous bisphosphonate therapy. The mechanism of action by which they may cause osteonecrosis is questionable. BRONJ is defined by the American Association of Oral and Maxillofacial Surgeons (AAOMS) and classified into four stages (0-3). Treatment of BRONJ depends on the stage of disease and includes conservative treatment (stage 0 and 1) and surgical treatment (surgical debridement in stage 2 and sequestrectomy in stage 3). Case report. We presented a patient who had breast cancer, with stage 3 of bisphosphonate-related osteonecrosis of the upper jaw after zoledronic acid therapy for diffuse metastasis of the vertebrae. Before the treatment with zoledronic acid the patient was treated by a dentist. The osteonecrosis of the upper jaw started a year and a half after the start of zoledronic acid therapy and after tooth 24 extraction. She was treated by an oral surgeon at the beginning according to the protocol of AAOMS. The patient was sent to a maxillofacial surgeon due to the disease progression, and after computed tomography (CT) examination resection of the upper jaw was done. Conclusion. BRONJ is a condition with the specific clinical presentation, and it can be very serious for the patient, therefore it is necessary to emphasize the importance of screening. The doctors in different specialties (oncologist, dentist, oral surgeon and maxillofacial surgeon) must cooperate and control the patients under treatment with bisphosphonates before the therapy starts, as well as during and after it, in order to prevent, recognize on time and treat properly this complication

Specific bronchial hyperreactivity and hypersensitivity in patients with allergic asthma

Background/Aim. Bronchial asthma is a disease that is characterized by the variability of the clinical picture, physical and functional status and the existence of bronchial hypersensitivity and hyperreactivity with varying degrees. Bronchial responsiveness and sensitivity are tested in patients with clinically suspected existence of asthma and normal spirometry test. The aim of the study was to analyze the patients with atopic asthma and study test results of skin sensitization to inhaled allergens, nonspecific bronchial hyperreactivity and specific hyperreactivity estimated by bronchial provocation tests with inhalant allergens. Methods. The prospective study at the Pulmonology Clinic of the Military Medical Academy in Belgrade Serbia, during 2014, included 70 male subjects aged 18–30 years, who had perennial asthma symptoms. All subjects were nonsmokers, with normal spirometry findings, with normal radiological chest findings and with no symptoms of respiratory infection over the past two months. All respondents were tested with skin prick tests with inhalant allergens and nonspecific bronchial provocation test with histamine. On the basis of histamine test, subjects were divided into two groups: the group I, in which there was a slight degree of hypersensitivity [provocation concentration of histamine causing a 20% fall in forced expiratory volume – PC20 = 6.09 ± 1.1 mg/mL], and the group II with negative histamine test (PC20 = 14.58 ± 6.34 mg/mL). Specific bronchial provocation test was performed in all patients, and the selection of the allergens was carried out based on the results of testing of skin hypersensitivity. Results. Results of skin sensitization show the highest incidence of mites Dermatophagoides pterronissinus (83.3% group I and 85.0% group II) followed by grass pollen (53.3% group I and 52.0% group II), and house dust (33.3% group I and 50.0% group II). There were no statistically significant differences in allergens between groups (p > 0.05). In both groups, spirometry findings were within normal values [forced vital capacity – FVC and forced expiratory volume 1 – FEV1 > 80% predictive value], but statistically significant difference was found in FEV1 between groups (p < 0.05). Specific bronchial provocation tests with solutions of inhaled allergens in both groups caused a significant decline in FEV1 (≥ 20%) in all patients individually. No statistically significant differences were found neither between groups, nor between individual allergens (average decline in FEV1: Group I 32.9 ± 2.4% and group II 31.5 ± 2.2%). Conclusion. There is no relationship between the degree of specific and non-specific bronchial hyperreactivity in patients with allergic asthma

Temperature dependence of catalytic cyclohexane partial oxidation in a polytetrafluoroethylene reactor

Polymer-supported Co(II) catalyst was prepared and its activity and selectivity in the partial oxidation of cyclohexane was determined at several temperatures in a polytetrafluoroethylene reactor ( PTFE). The catalyst was characterized by means of SEM-EDX, FTIR, diffuse reflectance UV-Vis, N-2 sorption, and mercury porosimetry. Activation energies were determined under steady state conditions for the net production of cyclohexanone and cyclohexanol and for cyclohexane and oxygen net consumption. Some activation energies were lower than the ones reported for the uncatalyzed process, indicating that the catalyst played an important role in the initiation of the free-radical reaction

Overall survival of patients with non-small cell lung cancer after surgery treatment

Background/Aim. Lung cancer is one of the most common malignant tumors. About 80% of all lung cancers are non-small cell lung cancer (NSCLC). According to histopathological characteristics, the most common types of NSCLC are squamous cell carcinoma and adenocarcinoma. The aim of this study was to evaluate the overall survival rate in the NSCLC patients initially received surgery according to its histopathological type and T – primary tumor, N –regional lymph nodes, M – distant metastasis (TNM) stages which were treated with surgical treatment, and after that, according to the TNM stage, chemotherapy protocols and/or radiation therapy. Methods. This retrospective case series study included all patients with NSCLC admitted to the Military Medical Academy in Belgrade in the period 2010–2015. A total number of selected patients was 85 (27 females and 58 males). Results. Out of 41 patients with squamous cell carcinoma, 19.5% deceased. On the other hand, in the group of patients with adenocarcinoma, 43.2% out of 44 patients deceased. The average cumulative survival was statistically significantly lower in the adenocarcinoma patients in comparison to the patients with squamous cell carcinoma (1,605.2 vs.1,304.8 days; p = 0.005). On the other hand, the average cumulative survival was statistically significantly lower in our patients in the recurrence group with adenocarcinoma in comparison to the recurrence group with squamous cell carcinoma (1,212.8 vs. 1,835.5 days; p = 0.032). Conclusion. Adenocarcinoma is more aggressive cancer in comparing to squamous cell carcinoma with lower overall survival in comparing to squamous cell carcinoma. Additional studies are needed to identify risk factors for recurrence after surgery, and to additionally explain role of tumor markers and molecular biological techniques in the progression of this kind of cancer

Influence of biological markers on overall survival in surgically treated patients with non-small cell lung cancer

Background/Aim. Non-small cell lung cancer (NSCLC) is one of the most common malignant tumors and a leading cause of cancer-related deaths. The aim of this study was to assess the impact of biological markers on the overall sur-vival rate in surgically treated NSCLC patients who received adjuvant chemotherapy and/or radiation therapy. Methods. This retrospective case series study included patients with NSCLC treated in the period between 2008 and 2017 at the Pulmonology Clinic and the Clinic for Chest Surgery, Mili-tary Medical Academy, Belgrade, Serbia. The survival analy-sis performed was based on immunohistological findings, histology type, and tumor, node, metastasis (TNM) stages. Results. The mortality rate was higher in the adenocarci-noma patient group compared to the squamous cell carci-noma group, albeit without statistical significance (58.3% vs. 31.2%, respectively; p = 0.175). Overall survival was shorter in the adenocarcinoma patient group compared to the squamous cell carcinoma group by approximately 750 days. Likewise, overall survival was shorter in the adenocarcino-ma patient group compared to the squamous cell carcinoma group for CD31 positive (p = 0.029), p-63 positive (p = 0.049), MMP-9 positive (p = 0.032), and matrix metallopro-teinase (MMP)-2 positive patients (p = 0.016). Conclusion. Adenocarcinoma is a more aggressive cancer type compared to squamous cell carcinoma with shorter overall survival. Our research showed a poorer overall survival in the adeno-carcinoma group of patients compared to the squamous cell carcinoma group in CD31, p-63, MMP-9, and MMP-2 posi-tive patients