DESIGN OF JOINTS IN STEEL TRUSS GIRDERS ACCORDING TO EUROCODES

U radu se obrađuje kodificirani proračun priključaka rešetkastih čeličnih nosača prema [1] i [2]. Pravila iz [1] koja se odnose na zavarene priključke u čeličnim rešetkastim nosačima su specifična i vrijede u vrlo ograničenim uvjetima, stoga se daje prikaz tih ograničenja te postupak dokaza otpornosti priključaka. Na numeričkom primjeru rešetkastog nosača od šupljih kvadratnih profila s direktnim zavarivanjem štapova ispune na pojasne štapove, ilustrirana je primjena pravila danih u [1].This article presents codified design of joints in steel truss girders, according to [1] and [2]. Rules in [1] which refers on welded joints in steel truss girders are specific and valid in very limited conditions. Therefore, it is given a review of those limitations and the procedure of calculation of joint resistance. The application of rules given in [1] is ilustrated on numerical example of steel truss girder, which consists of rectangular hollow sections with direct welding braces members on members of chord

Paratuberkuloza (johnova bolest) – osnovne karakteristike i stanje u našoj zemlji

Para tuberculosis or Johne's Disease, is a disease of the digestive tract of animals caused by Mycobacterium avium subspecies Para tuberculosis (M. a. Para tuberculosis). Para tuberculosis has been registered in many countries and it today presents one of the most widely-spread bacterial diseases in ruminants that causes severe economic damages. In our country, Para tuberculosis has not been studied extensively. The disease was registered for the first time in Serbia in 1995 in an isolated herd of sheep of the II-de-France breed, and serologically positive cattle were determined in 2001. Infection with M.a. Para tuberculosis occurs mostly in young animals which are the most sensitive to infection. The main source of infection is the feces of diseased animals. Furthermore, colostrums and milk of diseased animals can contain micro bacteria, and there is a possibility also of intra-uterine infection. A long period of incubation, a chronic course, and not always clear clinical picture render diagnosis of Para tuberculosis very complex, in spite of the existence of numerous diagnostic methods. There are a number of serological tests with which it is possible to detect antibodies against M.a. Para tuberculosis in infected animals. The most frequently used are complement binding reaction (CBR), the agar gel immunodiffusion test (AGID), and the immunioenzyme test (ELISA). The isolation of causes or parts of their genome, present important methods in the diagnosis of Para tuberculosis. Pieces of tissue obtained through autopsies or biopsies, feces or milk samples, can serve as material for isolation. A diagnosis of Para tuberculosis for dead or sacrificed animals is made on the grounds of path anatomical or path histological findings. Para tuberculosis of ruminants has certain similarities with Crohn's Disease in humans, from the clinical, morphological, and etiological aspects.Paratuberkuloza ili Johneova bolest je oboljenje digestivnog trakta životinja, prouzrokovano Mycobacterium avium subspecies paratuberculosis (M.a. paratuberculosis). Paratuberkuloza je ustanovljena u mnogim zemljama i ona danas predstavlja jednu od najrasprostranjenijih bolesti bakterijske etiologije preživara koja uzrokuje velike ekonomske štete. U našoj zemlji paratuberkuloza nije opsežnije izučavana. U Srbiji je prvi put bolest otkrivena 1995. godine u jednom izolovanom stadu ovaca rase Il de France, a serološki pozitivna goveda 2001. godine. Infekcija izazvana bakterijom M.a. paratuberculosis nastaje, uglavnom, kod mladih životinja koje su na infekciju i najosetljivije. Osnovni izvor infekcije je feces bolesnih životinja. Takođe, kolostrum i mleko obolelih životinja mogu da sadrže mikobakterije, a postoji mogućnost i intrauterine infekcije. Duga inkubacija, hronični tok i ne baš uvek jasno ispoljena klinička slika, čine dijagnostiku paratuberkuloze veoma kompleksnom i pored postojanja velikog broja dijagnostičkih metoda. Postoji nekoliko seroloških testova pomoću kojih je moguće da se otkriju antitela protiv M. a. paratuberculosis kod inficiranih životinja. Najčešće se koriste reakcija vezivanja komplementa (RVK), agar-gel imunodifuzioni test (AGID) i imunoenzimski test (ELISA). Izolacija uzročnika ili delova njegovog genoma, predstavljaju važne metode u dijagnostikovanju paratuberkuloze. Materijal za izolaciju mogu da budu delovi tkiva dobijeni obdukcijom ili biopsijom, feces i uzorci mleka. Dijagnoza paratuberkuloze na uginulim ili žrtvovanim životinjama postavlja se na osnovu patoanatomskog i patohistološkog nalaza. Paratuberkuloza preživara u kliničkom, morfološkom i etiološkom aspektu ima izvesne sličnosti sa Crohnovom bolesti ljudi

Kvantitativna i kvalitativna analiza Ag-NOR kod benignih i malignih tumora mlečne žlezde kuja

In this retrospective study, quantitative and qualitative analyses of argyrophil nucleolar organizer regions (AgNORs) in 54 malignant and 18 benign canine mammary gland tumors were made. Statistical analysis showed a significant difference in the mean number of AgNORs per cell between benign and malignant tumors (p lt 0.01). There was no significant difference in the mean number of AgNORs per cell between complex carcinomas, simple carcinomas and carcinomas in mixed tumors (p>0.05), as well as between adenomas and benign mixed tumors (p>0.05). Six different patterns of AgNOR distribution were observed. Types I, II, III and in only two cases, type IV, were observed in benign tumors, while all six types were observed in malignant tumors. The predominant types in malignant tumors were III, IV, V and VI. Cell types II, III and IV were predominant in malignant tumors with 5.5-7 AgNORs per cell, while cell types V and VI were dominant in tumors with more than 7 AgNORs per cell.U ovoj retrospektivnoj studiji izvršena je kvalitativna i kvantitativna analiza arigrofilnih organizatora nukleolusa (AgNORs), 54 maligna i 18 benignih tumora mlečne žlezde pasa. Uočene su statistički značajne razlike u prosečnom broju AgNORs po ćeliji između benignih i malignih tumora (p lt 0.01). Nisu dokazane statistički značajne razlike u prosečnom broju AgNORs po ćeliji između kompleksnih karcinoma, prostih karcinoma i karcinoma u mešovitom tumoru (p>0.05). Zapaženo je šest različitih tipova distribucije AgNORs. Tipovi I, II, III i samo u dva slučaja tip IV su uočeni kod benignih tumora, dok su kod malignih tumora uočeno svih šest tipova. Dominantni tipovi kod malignih tumora su III, IV, V and VI. Ćelije tipa II, III i IV dominiraju kod tumora kji imaju prosečno 5.5-7 AgNORs po ćeliji, dok tipovi V i VI su dominantni kod tumora koji imaju prosečno više od 7 AgNORs po ćeliji

The role of hepatic myofibroblasts in liver cirrhosis in fallow deer (Dama dama) naturally infected with giant liver fluke (Fascioloides magna)

Background: This paper describes liver cirrhosis in 35 fallow deer infected with the giant liver fluke, as well as the distribution, origin, and role of myofibroblasts in its development. Results: In liver of infected deer, stripes of connective tissue are wound around groups of degenerated and regenerated liver lobuli. In the connective tissue, lymphocytes and macrophages which often contain parasite hematin are also present. The walls of the bile ducts are thickened, the epithelium multiplied with mucous metaplasia, and desquamated cells, parasite eggs and brown pigment are present in their lumen. In the livers with cirrhosis, immunopositivity to alpha-SMA and desmin was observed in cells in portal and septal spaces, at the edge between fibrotic septa and the surrounding parenchyma and in perisinusoidal spaces. These cells vary in size, they are round, oval, spindle-shaped or irregular in shape, similar to vascular smooth muscle cells. The derangement of epithelial-mesenchymal interactions detected in chronic cholangiopathies is most probably the pro-fibrogenic mechanism in liver cirrhosis of fallow deer (Dama dama) infected with the giant liver fluke (Fascioloides magna). Conclusion: Myofibroblasts, especially hepatic stellate cells (HSCs), play an important role in the synthesis of extracellular matrix components in the development of parasitic fibrosis and cirrhosis in the liver of fallow deer

Uloga hepatičnih zvezdastih ćelija (HSCs) u razvoju fibroze jetre mačaka sa policističnim bubrezima (PKD)

Hepatic stellate cells (HSCs) play a significant role in hepatic fibrogenesis. In the following study we described the distribution of cells that express alpha-smooth muscle actin (α-SMA) and desmin in the cat liver with various degrees of fibrosis, as well as the significance of hepatic stellate cells and portal myofibroblasts in the genesis of fibrosis in cats with polycistic kidney disease. Liver samples from 15 necropsied Persian cats were examined microscopically, using H&E and Masson-trichrom methods and immunohistology for α-SMA and desmin. Liver fibrosis was confirmed in cats with terminal stage of chronic cholangiohepatitis and it was characterized by connective tissue septa which divide the liver parenchyma into irregular lobuli. Inflammation in the cat liver is connected with the activation of periductal myofibroblasts. The intensity of immunopositivity of perisinusoidal HSCs to α-SMA and desmin varied depending on the degree of fibrosis and was the strongest in livers of cats with cirrhosis.U ovom radu je opisana distribucija ćelija koje eksprimiraju α-glatkomišićni aktin (α-SMA) i dezmin u jetri mačaka sa različitim stadijumom fibroze, kao i značaj ovih ćelija u razvoju fibroze, kod mačaka sa policističnim bubrezima. Mikroskopski su ispitani uzorci jetre od 15 obdukovanih persijskih mačaka, korišćenjem HE i Mason-trihromnog bojenja i imunohistohemijski na α-SMA i dezmin. Fibroza jetre potvrđena je kod mačaka sa terminalnim stadijumom hroničnog holangiohepatitisa i odlikovala se prisustvom vezivno-tkivnih septi koje dele parenhim na nejednake lobuluse. Inflamacija u jetri mačaka u vezi je sa aktivacijom periduktalnih miofibroblasta. Intenzitet imunohistohemijske reakcije perisinusoidnih HSCs na α-SMA i dezmin razlikovala se od stepena fibroze i bio je najjači u jetri mačaka sa cirozom

Morfološko i imunocitohemijsko ispitivanje tumorskih ćelija kod Marekove bolesti

In this paper are described the macroscopic, microscopic and immunophenotypic characteristics of tumors in Marek’s disease (MD). Liver, kidneys, lungs, heart, proventriclus, ovary and nerves of sciatic plexus collected from 20 chickens aged 8 to 24 weeks were examined. Lymphoproliferative enlargement in various organs of focal and diffuse character was found. The affected organs were enlarged, compact and very brittle, irregular in shape, grayish-red or grayish-white and of fatty consistency. Most often characteristic changes were in the spleen, liver, proventriculus and ovary that usually had a compact or ribbed, fatty cauliflower like formation, different in size. On histological examination proliferation of small and medium size lymphocytes, lymphoblast cells, Marek’s disease cells and activated reticulum cells were found. Tumor proliferates predominantly consisted of lymphoblasts and had all the characteristics of a lymphoma. Immunohistochemical analysis revealed that lymphoma cells in MD are of CD3 + phenotype. In liver proliferates numerous CD79+ cells were found perivasculary, which is an interesting finding demanding further research.U ovom radu su opisane makroskopske, mikroskopske i imunofenotipske karakteristike tumora kod Marekove bolesti (MB). Ispitivanjem su bili obuhvaćeni jetra, bubreg, pluća, srce, žlezdani želudac, jajnik i nervi ishijadičnog pleksusa dvadeset pilića starosti između8i24 nedelje. U ispitivanom materijalu ustanovljeno je limfoproliferativno bujanje u različitim organima, fokalnog ili difuznog karaktera, pri čemu su zahvaćeni organi znatno povećani, kompaktni i veoma krti, često nepravilnog oblika, sivocrveni ili sivobeli, slaninastog izgleda. Najčešće i najkarakterističnije su bili promenjeni slezina, jetra, žlezdani želudac, jajnici koji obično predstavljaju kompaktne ili izbrazdane tvorevine poput karfiola, slaninastog izgleda i različite veličine. Histološki, u organima se nalaze proliferati malih i srednjih limfocita, zatim limfoblasta, ćelija Marekove bolesti i aktivisane retikulumske ćelije. Tumorski proliferati su predominantno sastavljeni od limfoblasta i imaju sve karakteristike limfoma. Imunohistohemijskom analizom je ustanovljeno da su ćelije limfoma kod MB predominantno T ćelijskog tipa, CD3 fenotipa. U proliferatu u jetri su nađene i brojne CD79 pozitivne ćelije lokalizovane perivaskularno, što predstavlja interesantan nalaz i zahteva dalja ispitivanja

Imunski odgovor pilića na kokcidijalnu infekciju

It is important to study the immunological response of chicken to infections caused by Eimeria spp. because control of this disease is a specific problem in conditions of intensive poultry production. The details of the protective mechanisms which are activated in the course of a coccidial infection have still not been satisfactorily explained, but it is known that cellmediated immunity plays a dominant role in defending the host from this agent. Intraepithelial lymphocytes (IEL) play a very important role in the local defense of intestinal mucosa from coccidial invasion. A certain number of IEL in chicken CD3 are positive and can be detected at the earliest on day 6 after hatching. Poultry IEL are mostly T-lymphocytes, most of which on their surface carry receptors for CD8 antigen, and since they are cytotoxic lymphocytes, they have an important role in resistance to secondary infection.Izučavanje imunskog odgovora pilića na infekciju prouzrokovanu Eimeria spp značajno je zbog toga, što suzbijanje ovog oboljenja predstavlja specifičan problem u uslovima intenzivne živinarske proizvodnje. Dosadašnji rezultati u razvoju imunoprofilakse, kao i sumnja u dostupnost novih antikokcidijala utiču na intenziviranje istraživanja u oblasti suzbijanja kokcidioze imunološkim metodama. Njihovo potpunije poznavanje može da doprinese uspešnijem iskorenjivanju bolesti, koja prati ekonomski značajnu intenzivnu proizvodnju mesa i jaja živine. Detalji zaštitnih mehanizama, koji su se aktivirali u toku kokcidijalne infekcije, još uvek nisu u potpunosti objašnjeni, ali se zna da imunitet ćelijski posredovan ima dominantnu ulogu u odbrani domaćina od ovog uzročnika

Reakcija proteina akutne faze kod krava sa subkliničkim mastitisom izazvanim staphilococcus aureus-om

Inflammation at a local and systemic level is a complex process that involves the synthesis of acute phase proteins (APPs) with multiple functions in the regulation of the inflammatory process itself. The aim of this work was to define local and systemic APPs response induced by natural Staph. aureus subclinical infection of the mammary gland in dairy cows with a different number of quarters involved. Midlactation dairy cows (n=30) were devided into three groups. First group were cows with bacteriologically negative milk samples (BN group), second group were cows with one quarter infected with Staph. aureus (SaQ1) and third group were cows with two quarters infected (SaQ2). Milk samples were analyzed for inflammation indicators: serum amyloid A (SAA) and somatic cell count (SCC). Serum samples where analyzed for SAA, haptoglobin (Hp), ceruloplasmin (Cp) and albumin concentration. Also, complete blood count (CBC) was done. SCC and SAA increased in quarter milk samples, being lowest in the BN group and highest in the SaQ2 group. In serum samples, SAA, Hp, Cp and albumin concentrations were significantly higher only in the SaQ2 group comparing with BN group. The leukocyte number, as well as hemoglobin concentration were in the physiological range in all three groups of cows. These results confirm that the magnitude of tissue injury has an impact on APPs concentration. They also demonstrate that cows having Staph. aureus sublinical infections of two mammary quarters have a more pronounced systemic APP response than cows with only one quarter involved.Lokalna i sistemska zapaljenjska reakcija predstavljaju kompleksne procese koji uključuju sintezu proteina akutne faze sa mnogobrojnim funkcijama u regulaciji samog zapaljenskog procesa. Cilj ovog rada je bio da se definiše lokalni i sistemski odgovor proteina akutne faze, koji je podstaknut prirodnom subkliničkom infekcijom mlečne žlezde sa Staph. aureus kod mlečnih krava, ali sa različitim brojem inficiranih četvrti. Mlečne krave (n=30) u sredini laktacionog perioda su podeljene u tri grupe. U prvoj grupi su bile krave sa bakteriološki negativnim uzorcima mleka (BN grupa), u drugoj krave sa jednom četvrti vimena inficiranom sa Staph. aureus (SaQ1), dok su u trećoj grupi bile krave sa dve četvrti vimena inficiranim sa Staph. aureus (SaQ2). Uzorke mleka smo analizirali na sledeće pokazatelje zapaljenja: serum amiloid A (SAA) i broj somatskih ćelija (BSĆ). U uzorcima krvnog seruma su ispitivani SAA, haptoglobin (Hp), ceruloplazmin (Cp) i koncentracija albumina. Takođe je urađena kompletna krvna slika. BSĆ i SAA su bili najniži u mleku iz BN grupe i najviši u SaQ2 grupi. U uzorcima krvnog seruma SAA, Hp, Cp i koncentracija albumina bili su značajno viši samo u SaQ2 grupi u poređenju sa BN grupom. Broj leukocita kao i koncentracija haptoglobina su bili u fiziološkim granicama kod sve tri grupe krava. Ovi rezultati ukazuju da krave koje imaju subkliničku infekciju sa Staph. aureus u dve četvrti vimena imaju i jače izraženi sistemski odgovor proteina akutne faze nego krave kojima je inficirana samo jedna četvrt vimena čime je pokazano da opseg povrede tkiva ima uticaj na koncentraciju proteina akutne faze u serumu

Dijagnostika i diferencijalna dijagnostika steroidnih hepatopatija pasa

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