Embryonic stem cells: culture techniques and their application

Matične stanice imaju sposobnost neograničenog umnažanja u kulturi i sposobnost diferenciranja u brojne tipove stanica. Razlikuju se po potentnosti; unipotentne matične stanice tvore samo jedan tip specijaliziranih stanica, multipotentne matične stanice mogu stvarati više tipova stanica i tkiva, pluripotentne matične stanice mogu stvoriti većinu ili sve stanične tipove odraslog organizma, totipotentne matične stanice mogu stvoriti sve stanice odraslog organizma kao i specijalizirana tkiva koja podupiru razvoj embrija. U ovom radu izložen je kratki prikaz matičnih stanica, tehnike uzgoja i moguća područja primjene od kliničkih do znanstveno-istraživačkih, kao i etičke polemike vezane za izvore i daljnju primjenu matičnih stanica. Iako matične stanice već 30 godina koristimo u liječenju leukemije ili prilikom transplantacije kože kod opsežnih opekotina, u novijoj povijesti medicine ova je tema postala predmetom mnogih polemika. Zasad se, kao izvor tih stanica koriste embriji nastali za potrebe umjetne oplodnje, iako se mogu koristiti i embriji nastali transplantacijom jezgre bilo koje stanice tijela donora u neoplođenu jajnu stanicu (terapijsko kloniranje). Kako se prilikom prikupljanja embrionalnih matičnih stanica zametak mora žrtvovati, znanstvenici se okreću drugim tipovima matičnih stanica, kao što su matične stanice odraslih ili, pak, matične stanice dobivene iz krvi pupkovine, a puno se truda i sredstava ulaže u istraživanje načina kako bi se iz diferenciranih stanica (primjerice kože) stvorile matične stanice bez uporabe jajnih stanica. U svakom slučaju, potraga za načinom kako matične stanice usmjeriti u diferencirane stanice koje će biti funkcionalne nakon presađivanja u živi organizam, u punom je jeku i predstavjaju nadu za oboljele od dijabetesa, Alzheimerove i Parkinsonove bolesti, srčanih bolesti, karcinoma, reumatoidnog artritisa i dr.In cell culture, stem cells have the ability of dividing indefinitely, as well as differentiating into numerous cell types. They differ in potency: unipotent stem cells develop into one specialised type of cells, multipotent ones are able to develop into multiple types of cells and tissues, pluripotent ones into the majority or all cell types of a mature organism, totipotent cells into all cell types of a mature organism, as well as specialised tissues that support embrional development. This paper presents a brief overview of stem cell, cultivation techniques and possible areas of clinical applications and the scientific research, as well as ethical controversies related to sources and further application of stem cells. Although stem cells have been used in the treatment of leukemia and in treatments of skin burns, by using transplantation, for over thirty years now, in the recent history of medicine this topic became the cause of many controversies. Nowadays, stem cells are mostly derived from embryos made by artificial insemination, but embryos made by transplantation of the nucleus of the donor's body cells into an unfertilized egg cell (therapeutic cloning) could be used as well. Since the embryo is destroyed during the act of acquiring EM cells, scientists turn to other types of stem cells, such as adult stem cells or stem cells which can be derived from the blood of umbillical cords. A lot of effort and resources is put into researching ways of creating stem cells from differentiated cells (like skin cells) without the usage of egg cells. In any case, the quest for a way to guide stem cells into differentiated cells that will be functional after transplantation into a living organism is in full throtle. This quest gives hope to those suffering from diabetes, Alzheimer's and Parkinson's disease, cardiovascular diseases, carcinomas, rheumatoid arthritis etc

Morphological characteristics of three classic forms of natural equine glanders - a disease with high zoonotic significance

Equine glanders is a severe bacterial disease known since ancient times. Although eradicated in the most part of the world it is now considered re-emerging. Considering very scarce literature data, we used from formalin fixed collection material: nasal septum, lung and skin specimens from naturally infected horses. Tissues were grossly examined and photographed. Tissue samples, after standard processing, were stained with HE, Congo red and Groccot and microscopically examined. Gross changes include nodules and ulcers in the nasal mucosa with granulation and scarring, pyogranulomas in the lung tissue and nodules and ulcers of the skin. Microscopically marked inflammation of affected tissues with neutrophilic and mononuclear infiltration and fibrous tissue proliferation were seen. As a potent zoonotic agent it has been already used as a biological weapon in the past

Iron loss reduction in an interior PM automotive alternator

Copyright © 2006 IEEEThis paper examines the iron loss characteristics of a high-flux interior permanent-magnet machine. The machine was designed as a concept demonstrator for a 6-kW automotive alternator and has a wide field-weakening range. Initial experimental results revealed a high iron loss during field-weakening operation. Finite-element analysis was used to investigate the cause of the high iron losses and to predict their magnitude as a function of speed. The effects of changes in the machine design were examined in order to reduce iron losses and hence improve the machine performance.Vlatka Životi´c-Kukolj, Wen L. Soong, and Nesimi Ertugru

Clustering and Classification in Option Pricing

This paper reviews the recent option pricing literature and investigates how clustering and classification can assist option pricing models. Specifically, we consider non-parametric modular neural network (MNN) models to price the S&P-500 European call options. The focus is on decomposing and classifying options data into a number of sub-models across moneyness and maturity ranges that are processed individually. The fuzzy learning vector quantization (FLVQ) algorithm we propose generates decision regions (i.e., option classes) divided by ‘intelligent’ classification boundaries. Such an approach improves generalization properties of the MNN model and thereby increases its pricing accuracy

Option Pricing With Modular Neural Networks

This paper investigates a nonparametric modular neural network (MNN) model to price the S&P-500 European call options. The modules are based on time to maturity and moneyness of the options. The option price function of interest is homogeneous of degree one with respect to the underlying index price and the strike price. When compared to an array of parametric and nonparametric models, the MNN method consistently exerts superior out-of-sample pricing performance. We conclude that modularity improves the generalization properties of standard feedforward neural network option pricing models (with and without the homogeneity hint)

Uticaj LPS i IL-33 na adultne matične tkiva periodoncijuma: funkcijske promene i aktivirani molekulski mehanizmi

Contemporary methods for treating various diseases of the oral cavity, caused by congenital deformities, mechanical damage or damage caused by inflammatory or tumor diseases can be a complex clinical task, given that the requirement for restoration of function and aesthetics of the orofacial region is imposed. The supporting tissue of the tooth in which the tissue of the periodontium represents the connection between the teeth and the alveolar bone, has an important role in maintaining the structure and function of the orofacial system. The tissue of the periodontium is very rich with mesenchymal stem cells (MSC) and can be a suitable source of MSC population for potential therapeutic use. Due to periodontium damage, the establishment of teeth structure and function, and consequently the orofacial system, is very difficult, even with the application of the most modern prosthetic treatments. However, functional features оf MSC from periodontium (PD-MSC) have not been fully revealed, which is a necessary requirement for their application. A particularly important aspect is understanding of PD-MSC’s behavior in the inflammatory microenvironment, since the periodontium destruction is most often caused by periodontal disease, chronic inflammatory disease of the supporting tissue of the teeth that can lead to tooth loss. In addition, inflammation of the teeth supportive tissue may be an accompanying complication after the dental implant, which also indicates the need to improve existing prosthetic treatments. The aim of the research covered by this dissertation was to obtain data about effects of factors frequently associated with the periodontium niche on the functional properties of PD-MSC. The influence of LPS, as a strong initiator of the inflammatory process, on the regenerative and immunomodulatory PD-MSC was examined. On the molecular level mechanisms mediating the effects of LPS were determined, wherein the activity of MAPK (Mitogen-Activated Protein Kinases) signaling pathways was determined. In addition, the effect of IL-33, as an endogenous alarm signal, on the regenerative properties of PD-MSC was examined...Savremeni načini lečenja različitih oboljenja usne duplje, nastalih usled urođenih deformiteta, mehaničkih oštećenja ili poremećaja uzrokovanim inflamatornim ili tumorskim oboljenjima mogu predstavljati kompleksan klinički zadatak s obzirom da se nameće zahtev obnove funkcije, ali i estetike orofacijalnog regiona. Značajnu ulogu u održanju strukture i funkcije orofacijalnog sistema ima potporno tkivo zuba u okviru koga tkivo periodoncijuma predstavlja vezu između zuba i alveolarne kosti. Tkivo periodoncijuma je bogato mezenhimskim matičnim ćelijama (MMĆ), te može biti pogodan izvor populacije MMĆ za potencijalnu terapijsku primenu. Usled oštećenja tkiva periodoncijuma uspostavljanje strukture i funkcije zuba, a time i orofacijalnog sistema je veoma otežano čak i uz primenu najsavremenijih protetskih tretmana. Ipak, funkcijske osobine MMĆ periodoncijuma (PD-MMĆ) nisu u potpunosti ispitane, što predstavlja neophodan uslov za njihovu primenu. Posebno važan aspekt predstavlja poznavanje ponašanja PD-MMĆ u inflamatornoj mikrosredini, budući da do razaranja tkiva periodoncijuma najčešće dolazi usled parodontopatije, hroničnog inflamatornog oboljenja potpornog tkiva zuba koje može dovesti do gubitka zuba. Pored toga, inflamacija potornog tkiva može biti prateća komplikacija nakon postavljanja dentalnih implantata što takođe ukazuje na potrebu za poboljšavanjem postojećih protetskih tretmana. Istraživanja obuhvaćena ovom disertacijom imala su za cilj dobijanje podataka o uticaju faktora koji se mogu naći u niši tkiva periodoncijuma na funkcijska svojstva PD-MMĆ. Ispitivan je uticaj LPS, kao snažnog inicijatora inflamatornog procesa, na regenerativna i imunomodulatorna svojstva PD-MMĆ..

Obtenção de perfil protéico bidimensional de nódulos de Phaseolus vulgaris induzidos pro Rhizobium sp. NGR234 e pela estirpe nopJ-

Orientador: Roseli WassemMonografia (Bacharelado) - Universidade Federal do Paraná. Setor de Ciências Biológicas. Curso de Graduação em Ciências BiológicasResumo : O cultivo de leguminosas de interesse agrícola depende de associações simbióticas com microorganismos capazes de fixar nitrogênio atmosférico, chamados rizóbios. O cultivo de feijão no Brasil apresenta uma produtividade média baixa, com amplitude de variação muito alta: desde 400 kg/ha até mais de 3000 kg/ha. Além disso, é essencialmente dependente de fertilizantes nitrogenados químicos, cuja fabricação demanda um alto custo. Considerando que o feijão constitui importante fonte de proteína da alimentação humana, principalmente em países pobres da África e América do Sul, é notável a importância do desenvolvimento de tecnologias de baixo custo que aumentem a produtividade e não causem prejuízos ao meio ambiente. O uso de inoculantes microbianos no cultivo de soja aproxima-se de 100% e representa uma economia anual de 8 bilhões de reais por ano no Brasil com fertilizantes químicos. No entanto, em outras leguminosas o uso de inoculantes ainda é limitado, devido ao desconhecimento dos fatores importantes para o estabelecimento de uma interação eficiente. O feijão comum (Phaseolus vulgaris) é colonizado pelo Rhizobium sp. NGR234, em um processo que envolve a ação sincronizada de genes de nodulação, fixação de nitrogênio e do sistema de secreção do tipo III (T3SS). NopJ é uma proteína efetora secretada pelo T3SS em NGR234 e é diretamente injetada no citoplasma da célula vegetal, mas sua função ainda é descohecida. Curiosamente, uma estirpe mutante nopJnodula o Phaseolus mais eficientemente que a estirpe selvagem. A fim de entender o efeito do NopJ na interação entre Rhizobium sp. NGR234 e P. vulgaris, foram cultivados feijões sob condições estéreis e inoculados com as estirpes selvagem e nopJde NGR234. Os nódulos foram coletados 4 e 6 semanas após a inoculação. Extratos protéicos foram obtidos para análises em géis de eletroforese bidimendional, utilizando tiras de gradiente de pH imobilizado e SDS-PAGE. Os géis foram corados com Coomassie Blue G-250, e os perfis protéicos analisados. A posterior identificação das proteínas através de MALDI-TOF, irá contribuir com a elucidação dos mecanismos de interação entre Rhizobium-Phaseolus

The efficiency of caffeic acid on oxidative stress and angiogenesis in Ehrlich ascites tumor

Napredovanje razvoja tumorskih stanica uključuje preživljavanje, širenje, invaziju, angiogenezu i metastaziranje. Reaktivne vrste kisika (ROS) su povezane s brojnim staničnim funkcijama, kao što su stanična proliferacija, diferencijacija, apoptoza i angiogeneza. Prema tome, inhibicija ROS, početnog koraka rasta tumora i angiogeneze, je obećavajući pristup za kemoprevenciju raka i terapiju. Kafeinska kiselina (CA) je biološki aktivna sastavnica propolisa koja pokazuje antioksidativna, protuupalna, antiproliferativna, citostatska, antiangiogena i antineoplastična svojstva. U ovom radu istraživali smo učinak kafeinske kiseline na rast tumora, tumorsku angiogenezu, funkcionalnu sposobnost makrofaga i makrofagnu polarizaciju kao oksidacijski stres u miševa. EAT stanice (2,5 x 106) su injicirane intraperitonealno (ip) u Swiss albino miševe. Nakon inokulacije tumora, miševi su injicirani ip CA u dozi od 40 i 80 mg kg tjelesne težine kroz 10 dana ili u fazi eksponencijalnog rasta od 5 dana nakon injekcije stanica tumora (na dan 5, 7, 9). Na dan 11, analizirali smo ukupni broj stanica ascitesa u peritonealnoj šupljini, volumen ascitesa, diferencijalnu analizu stanica prisutnih u peritonealnoj šupljini, funkcionalna aktivnost makrofaga, antiangiogenične i antioksidativne parametre. CA je inhibirala rast stanica EAT i nastanak ascitesa u peritonealnoj šupljini miševa nositelja EAT. Nadalje, rezultati smanjenja peritonealne angiogeneze i mikrožilne gustoće pokazuju anti-angiogeni potencijal CA in vivo. CA smanjuje razinu NO stanicama EAT, dok razina NO je povećana u peritonealnim makrofagima. Sve u svemu, možemo zaključiti da CA može aktivirati makrofage i povećati njihov citotoksični učinak kroz povećamu proizvodnje NO te spriječiti rast tumora i angiogenezu. Nadalje, CA selektivno povećava nastanak ROS-a u stanicama tumora tijekom 10 dana obrade i mi pretpostavljamo da unutarstanična proizvodnja ROS-a može biti kritičan čimbenik u indukciji apoptoze i CA-selektivnog ubijanja stanica tumora, a čini se da inhibicija angiogeneze i rasta stanica EAT tumora u uznapredovalom stadiju, kada stanice ulaze u eksponencijalnu fazu rasta temelji se na antioksidativnom kapacitetu CA.Progression of tumor cell development involves survival, proliferation, invasion, angiogenesis, and metastasis. Reactive oxygen species (ROS) are associated with multiple cellular functions such as cell proliferation, differentiation, apoptosis and angiogenesis. Therefore, inhibition of the ROS, the initial step of tumor growth and angiogenesis, is a promising strategy for cancer chemoprevention and therapy. Caffeic acid (CA), an active component of propolis extract which exhibits antioxidant, antiinflammatory, antiproliferative, cytostatic, anti-angiogenic and most improtantly, antineoplastic properties. In the present study we investigated the effect of of caffeic acid on tumor growth, tumor angiogenesis, functional ability of macrophages and macrophage polarization as well as oxidative stress in mice. EAT cells (2. 5 x 106) were implanted intraperitoneally (ip) in Swiss albino mice. After tumor inoculation, mice were injected ip with CA at dose of 40 and 80 mg/kg bw during 10 days or in exponential growth phase from the 5 days after tumor cell injection (on day 5, 7, 9). On day 11, ascites volume, the total number of cells, differential count of the cells present in the peritoneal cavity, functional activity of macrophages, anti-angiogenic and antioxidant parameters were determined. The growth of EAT cells and formation of ascites in the peritoneum of EAT-bearing mice was inhibited by CA. Further, results on decrease in the peritoneal angiogenesis and microvessel density show the anti-angiogenic potential of CA in vivo. CA decreased NO level in tumor cells whereas NO level was increased in peritoneal macrophages. Taken together, we conclude that CA may increase the cytotoxic actions of macrophages by increasing NO and inhibit tumor growth and angiogenesis. Moreover, CA selectively caused escalation in the ROS formation in EAT cells during 10 days treated and we speculated that intracellular generation of ROS could be a critical factor in the induction of apoptosis and CA-selective killing of tumor cells while it appears that inhibition of angiogenesis and tumor growth EAT cells in advanced stages when the cells entered into exponential growth period based on the antioxidant capacity CA

Embryonic stem cells: culture techniques and their application

Matične stanice imaju sposobnost neograničenog umnažanja u kulturi i sposobnost diferenciranja u brojne tipove stanica. Razlikuju se po potentnosti; unipotentne matične stanice tvore samo jedan tip specijaliziranih stanica, multipotentne matične stanice mogu stvarati više tipova stanica i tkiva, pluripotentne matične stanice mogu stvoriti većinu ili sve stanične tipove odraslog organizma, totipotentne matične stanice mogu stvoriti sve stanice odraslog organizma kao i specijalizirana tkiva koja podupiru razvoj embrija. U ovom radu izložen je kratki prikaz matičnih stanica, tehnike uzgoja i moguća područja primjene od kliničkih do znanstveno-istraživačkih, kao i etičke polemike vezane za izvore i daljnju primjenu matičnih stanica. Iako matične stanice već 30 godina koristimo u liječenju leukemije ili prilikom transplantacije kože kod opsežnih opekotina, u novijoj povijesti medicine ova je tema postala predmetom mnogih polemika. Zasad se, kao izvor tih stanica koriste embriji nastali za potrebe umjetne oplodnje, iako se mogu koristiti i embriji nastali transplantacijom jezgre bilo koje stanice tijela donora u neoplođenu jajnu stanicu (terapijsko kloniranje). Kako se prilikom prikupljanja embrionalnih matičnih stanica zametak mora žrtvovati, znanstvenici se okreću drugim tipovima matičnih stanica, kao što su matične stanice odraslih ili, pak, matične stanice dobivene iz krvi pupkovine, a puno se truda i sredstava ulaže u istraživanje načina kako bi se iz diferenciranih stanica (primjerice kože) stvorile matične stanice bez uporabe jajnih stanica. U svakom slučaju, potraga za načinom kako matične stanice usmjeriti u diferencirane stanice koje će biti funkcionalne nakon presađivanja u živi organizam, u punom je jeku i predstavjaju nadu za oboljele od dijabetesa, Alzheimerove i Parkinsonove bolesti, srčanih bolesti, karcinoma, reumatoidnog artritisa i dr.In cell culture, stem cells have the ability of dividing indefinitely, as well as differentiating into numerous cell types. They differ in potency: unipotent stem cells develop into one specialised type of cells, multipotent ones are able to develop into multiple types of cells and tissues, pluripotent ones into the majority or all cell types of a mature organism, totipotent cells into all cell types of a mature organism, as well as specialised tissues that support embrional development. This paper presents a brief overview of stem cell, cultivation techniques and possible areas of clinical applications and the scientific research, as well as ethical controversies related to sources and further application of stem cells. Although stem cells have been used in the treatment of leukemia and in treatments of skin burns, by using transplantation, for over thirty years now, in the recent history of medicine this topic became the cause of many controversies. Nowadays, stem cells are mostly derived from embryos made by artificial insemination, but embryos made by transplantation of the nucleus of the donor's body cells into an unfertilized egg cell (therapeutic cloning) could be used as well. Since the embryo is destroyed during the act of acquiring EM cells, scientists turn to other types of stem cells, such as adult stem cells or stem cells which can be derived from the blood of umbillical cords. A lot of effort and resources is put into researching ways of creating stem cells from differentiated cells (like skin cells) without the usage of egg cells. In any case, the quest for a way to guide stem cells into differentiated cells that will be functional after transplantation into a living organism is in full throtle. This quest gives hope to those suffering from diabetes, Alzheimer's and Parkinson's disease, cardiovascular diseases, carcinomas, rheumatoid arthritis etc