Rat duodenal motility in vitro: Prokinetic effects of DL-homocysteine thiolactone and modulation of nitric oxide mediated inhibition

Homocysteine is a significant but modifiable risk factor for vascular diseases. As gastrointestinal smooth musculature is similar to blood vessel muscles, we investigated how elevated homocysteine levels affect nitric oxide-mediated neurotransmission in the gut. There is accumulated evidence that a dysfunction of NO neurons in the myenteric plexus may cause various diseases in the gastrointestinal tract such as achalasia, diabetic gastroparesis and infantile hypertrophic pyloric stenosis. In the present study, we aimed to assess the effects of homocysteine on NO-mediated responses in vitro, and to examine the effects of DL-homocysteine thiolactone on the spontaneous motility of rat duodenum and nitrergic neurotransmission. DL-homocysteine thiolactone concentration of 10 μmol/L leads to the immediate increase in tone, amplitude and frequency of spontaneous movements in isolated rat duodenum. L-NAME (30 μmol/L) leads to an increase in basal tone, amplitude and frequency of spontaneous contractions. The relaxations induced by EFS were significantly reduced in duodenal segments incubated in DL-homocysteine thiolactone compared with the control group. EFS-induced relaxations were inhibited by L-NAME in both experimental and control groups. These results suggest that a high level of homocysteine causes an important impairment of non-adrenergic non-cholinergic innervation of the rat duodenum. [Projekat Ministarstva nauke Republike Srbije, br. 175043

FOUR CASES OF APPENDICEAL NEUROMA MIMICKING ACUTE APPENDICITIS

Herein we report four cases of appendiceal neuroma found during a short (one month) monitoring period in patients with severe pain in the lower right abdominal quadrant that underwent appendectomies. Tissue samples were routinely processed to obtain histological sections that were stained with hematoxylin and eosin (H&E) and further with anti-S100 protein antibody. Characteristics of appendiceal neuroma were noted in these cases and they included the absence of mucosal and lymphoid tissue of the appendices, stroma with spindle-shaped cells that were positively stained with anti-S100 protein antibody. This clinical entity is important due to a possible misdiagnosis with acute appendicitis or exacerbation of inflammatory bowel disease and great attention should be paid during the clinical evaluation of similar symptoms.Key words: appendiceal neuroma, misdiagnosis, lumen obliteration, immunohistochemistry, S100 protei

Magneto-dielectric properties of ferrites and ferrite/ferroelectric multiferroic composites

Ni-Zn ferrites, with the general formula Ni1-xZnxFe2O4 (x = 0.0, 0.3, 0.5, 0.7, 1.0), CoFe2O4, BaTiO3 and PbZr0.52Ti0.48O3 powders were synthesized by auto-combustion method. The composites were prepared by mixing the appropriate amounts of individual phases, pressing and conventional sintering. X-ray analysis, for individual phase and composites, indicated the formation of crystallized structure of NiZnFe2O4, BaTiO3 and PbZr0.52Ti0.48O3 without the presence of secondary phases or any impurities. SEM analyses indicated a formation of uniform grain distribution for ferromagnetic and ferroelectric phases and formation of two types of grains, polygonal and rounded, respectively. Magneto-dielectric effect was exhibited in all samples because of the applied stress occurring due to the piezomagnetic effect and the magnetic field induced the variation of the dielectric constant. For all samples the dielectric constant was higher in applied magnetic field. At the low frequency, the dispersion of dielectric losses appeared, while at the higher frequency the value of tan δ become constant (Maxwell-Wagner relaxation). Investigation of J-E relation between leakage and electric field revealed that both nickel zinc ferrite and composites have three different regions of conduction: region with ohmic conduction mechanism, region with the trap-controlled space charge limited current mechanism and region with space charge limited current mechanism

Application of radiovisiography (digital radiology) in dental clinical practice

Introduction. Radiovisiography (RVG) as the latest imaging technique in dentistry with the minimal radiation exposure of the patient and numerous possibilities to process the images has many advantages over classic radiography. Case report. We presented an interesting clinical endodontic case of primary posted diagnosis of traumatic periodontitis of upper right canine upon orthodontics treatment. As the patient previously had been exposed to alleged high dose of radiation the patient agreed to minimal exposition using digital RVG. The options of the tool bar of RVG Trophy device enabled the solving of ethiologic factor of presented periodontitis. The enigma of the symptoms on the ’overfilled’ root canal was solved zooming and 3-D analysis avoiding periapical surgery owing to the patience of the patient and the dentist in a couple of days. Conclusion. By applying RVG technique the time for diagnostic procedure is much shorter in comparison with traditional dental radiography enabling archiving and follow-up the presented case in the course of time

Intellectual property protection of pharmaceutical products and processes

The role of intellectual property is significantly increasing within new international economic and commercial relationships. Intellectual capital is being increasingly recognised as one of the most important domains belonging to the greatest and the most powerful world companies. Intellectual property protection is a complex category and it comprises legal, technical and economical-financial aspects

Mathematical model of unsteady gas to solid particles heat transfer in fluidized bed

The mathematical model of unsteady one-dimensional gas to particles heat transfer for non-isothermal fluidized bed with periodic heating of solid particles has been described. The method of numerical solution of governing differential equations, the algorithm and the computer program, have been presented. By using mathematical model and computer program, the temperature profiles for interstitial gas, gas in bubbles, and solid particles along the height of fluidized bed in function of time, have been determined. The results obtained on the basis of prediction method are compared to the experimental results of the authors; the satisfactory agreement has been found for interstitial gas temperature and solid particle temperature. On the basis of this comparison, the mathematical model has been verified

Efekat sadržaja umreživača na svojstva bubrenja inteligentnih gelova

This paper presents the procedure for the synthesis of hydrogels based on N-isopropylacrylamide (NIPAM) and 2-hydroxypropyl methacrylate (HPMet) using dioxan as a solvent. Hydrogels were obtained by radical polymerization using different contents of ethylene glycol dimethacrylate as a cross-linker and benzoyl peroxide as the initiator. In the FTIR spectra of poly(N-isopropylacrylamide-co- 2-hydroxypropylmethacrylate) (p(NIPAM-HPMet)) xerogel, new absorption bands are present and there are no specific bands characteristic of a monomer NIPAM, which indicates that copolymerization was performed. SEM micrographs show porous surfaces of xerogels. The aim of this work was the investigation of the swelling behavior for all synthesized hydrogels with different cross-linker content at the temperature from 20 to 40°C. The sample of p(NIPAM-HPMet) with the lowest cross-linker content reached the highest swelling degree at 20°C (α=20.23). The degree of swelling decreased with increa-sing the cross-linker content and temperature, so the samples with highest cross-linker content at 40°C reached the swelling degree of 2.05.U radu je izvršena sinteza hidrogelova na bazi N-izopropilakrilamida (NIPAM) i 2-hidroksipropil metakrilata (HPMet), primenom dioksana kao rastvarača. Hidro­gelovi su dobijeni radikalskom polimerizacijom uz upotrebu različitog sadržaja etilenglikoldimetakrilata (EDGM) kao umreživača i benzoil peroksida kao inicijatora. U FTIR spektrima kserogelova poli(N-izopropilakrillamid-ko-2-hidrok­sipropil metakrilata) (p(NIPAM-HPMet)) prisutne su nove apsorpcione trake, a nisu prisutne pojedine trake karakteristične za monomere, što ukazuje na izvršenu kopolimerizaciju. SEM mikrografije pokazuju poroznu površinu ksero­gelova. Svojstva pri bubrenju svih sintetisanih hidrogelova praćena su na temperaturama od 20 do 40°C. Najveću sposobnost bubrenja pokazao je uzorak p(NIPAM-HPMet)-a sa najmanjim sadržajem umreživača na 20°C (α = 20,23). Sposobnost bubrenja opada pri povećanju sadržaja umreživača i temperature, tako da uzorci sa najvećim sadržajem umreživača (3 mol% EGDM-a) na 40°C dostižu stepen bubrenja od samo 2,05

Evaluation of pathological parameters and morphometric data of desmoplastic lobular breast carcinoma

Background: Invasive lobular breast cancer (ILC) is the second most frequent form of breast cancer. While cancer cells are regularly investigated, tumor stroma represents a highly unexplored field. Aims: The aim of this study is to perform a detailed investigation of clinical, immunohistochemical, and morphometric characteristics of desmoplastic (D) and nondesmoplastic (ND) ILC. Materials and Methods: This study included twenty cases of ILC that were divided into two groups designated as D and ND groups. Medical histories and diagnosis data were obtained from the archives of the Center of Pathology, Clinical center Niš (Serbia). Morphometric analysis of hematoxylin and eosin stained slides was performed using ImageJ software, and the obtained data were further statistical processed. Results: Statistical analyses of the data revealed that no significant differences between D and ND groups when patient age, estrogen receptor (ER), and progesterone receptor (PR) expressions and morphometrical parameters (such as the distance between groups of cancer cells and nucleocytoplasmic ratio) were compared. However, D and ND groups statistically, significantly differed in the occurrence of axillary lymph node metastasis, and when the ER and PR data were included, in certain nuclear parameters (cell/nucleus area, perimeter, Feret′s diameter, and circularity). Conclusions: Desmoplastic stroma was observed more frequently in patients without axillary lymph node metastases, whereas the expression of ER and PR had no influence on its development. According to the measured morphometric parameters larger cells/nuclei belonged to ND group

Influence of monomer and crosslinker molar ratio on the swelling behaviour of thermosensitive hydrogels

The synthesis of the poly(N-isopropylacrylamide-co-2-hydroxypropylmethacrylate) hydrogel along with the analysis of the residual monomers content and influence of monomer and crosslinker molar ratios on the swelling behaviour was investigated. Synthesis of thermosensitive hydrogel based on N-isopropylacrylamide was carried out with the molar ratios of 5, 10, 15 and 20 mol. % of monomer 2- hydroxypropyl-methacrylate, in the presence of ethylene glycol dimethacrylate as a crosslinker (1, 1.5, 2 and 3 mol. %) and 2,2'-azobis(2-methylpropionitril) as an initiator in acetone. The quantities of residual monomers in the synthesized copolymers were determined by HPLC method, ranging from 0.19 to 0.49 % for N-isopropylacrylamide and from 0.13 to 0.63 % for 2-hydroxypropyl-methacrylate, counting the amount of xerogel. The hydrogels swelling ratio depending on time at 20 and 40°C was examined. It was found that hydrogel with 5 mol. % 2-hydroxypropyl-methacrylate and 1 mol. % ethylene glycol dimethacrylate had the highest degree of swelling (α = 29.59) at 20°C, and that hydrogel with 20 mol. % 2-hydroxypropyl-methacrylate and 3 mol. % ethylene glycol dimethacrylate had the lowest swelling degree (α = 2.17) at 40°C