1,720,956 research outputs found
Antitumor effect of the essential oil of the mastic tree (Pistacia lentiscus L.) on breast cancer cell lines
No full textCilj istraživanja: Cilj ovog istraživanja je ispitati potencijalno citotoksično i antitumorsko djelovanje eteričnog ulja izoliranog iz lista tršlje (Pistacia lentiscus L.). na dvije humane karcinomske stanične linije dojke – MDA-MB-231 i MCF-7. Pretpostavljeno je da će se broj karcinomskih stanica smanjiti nakon izlaganja određenim koncentracijama eteričnog ulja tršlje u usporedbi s kontrolnom skupinom.
Materijali i metode: Kako bi izmjerili postotak preživjelih stanica tj. staničnu metaboličku aktivnost, korišten je neradioaktivni kolorimetrijski MTT testni sustav koji se zasniva na redukciji žute tetrazolijeve soli u ljubičaste kristale formazana pomoću metabolički aktivnih stanica. Eterična ulja su se inkubirala u rasponu koncentracija od 1 do 500 µg/mL tijekom 72 sata u tri replikata, a apsorbancija se mjerila na 570 nm na čitaču mikropločica nakon 24, 48 i 72 sata.
Rezultati: Rezultati ovog istraživanja nakon izlaganja karcinomskih stanica različitim koncentracijama eteričnog ulja biljke tršlje se razlikuju za pojedinu karcinomsku staničnu liniju dojke. Najznačajniji rezultati djelovanja na MDA-MB-231 staničnu liniju su nakon inkubacije od 48 sati pri koncentraciji od 500 µg/ml gdje se stanična viabilnost smanjila na 19 % te pri koncentraciji od 250 µg/ml nakon 24 sata gdje se stanična viabilnost smanjila na 52 %. Kod stanične linije MCF-7 najznačajniji rezultati su nakon inkubacije od 48 sati pri koncentraciji od 500 µg/ml gdje se stanična viabilnost smanjila na 30 % te pri koncentraciji od 500 µg/ml nakon 24 sata gdje se stanična viabilnost smanjila na 36 %.
Zaključak: Temeljem dobivenih rezultata ovog istraživanja zaključujemo da eterično ulje lista tršlje ima potencijal u liječenju karcinoma dojke te da u određenom postotku ubija karcinomske stanice. U odnosu na staničnu liniju MDA-MB-231, eterično ulje lista tršlje pokazuje slabije citotoksično djelovanje na staničnu liniju MCF-7. IC50 vrijednost je postignuta za obe stanične linije te se ona smanjuje s povećanjem trajanja inkubacije. Vrijednost je niža kod MDA-MB-231 stanične linije u odnosu na MCF-7 staničnu liniju.Aim of the study: The aim of this research is to examine the potential cytotoxic and antitumor effect of the essential oil isolated from the leaves of the Pistacia lentiscus L. plant on two human breast cancer cell lines - MDA-MB-231 and MCF-7. It was hypothesized that the number of cancer cells will decrease after exposure to certain concentrations of essential oil of mastic tree compared to the control group.
Materials and methods: In order to measure the percentage of surviving cells, i.e. cellular metabolic activity, a non-radioactive colorimetric MTT test system was used, which is based on the reduction of yellow tetrazolium salt into purple formazan crystals by metabolically active cells. Essential oils were incubated in the concentration range from 1 to 500 µg/mL for 72 hours in three replicates, and the absorbance was measured at 570 nm on a microplate reader after 24, 48 and 72 hours. Results: The results of this research after exposure of cancer cells to different concentrations of the essential oil of the mastic tree differ for each breast cancer cell line. The most significant results of the effect on the MDA-MB-231 cell line are after incubation for 48 hours at a concentration of 500 µg/ml where cell viability decreased to 19% and at a concentration of 250 µg/ml after 24 hours where cell viability decreased to 52 %. In the case of the MCF-7 cell line, the most significant results were obtained after incubation for 48 hours at a concentration of 500 µg/ml, where cell viability decreased to 30%, and at a concentration of 500 µg/ml after 24 hours, where cell viability decreased to 36%.
Conclusion: Based on the results of this research, we conclude that the essential oil of the Pistacia Lentiscus L. leaf has potential in the treatment of breast cancer and that it kills cancer cells in a certain percentage. Compared to the MDA-MB-231 cell line, mastic tree leaf extracts show a weaker cytotoxic effect on the MCF-7 cell line. The IC50 value was reached for both cell lines and it decreases with increasing incubation time. The value is lower in MDA-MB-231 cell line compared to MCF-7 cell line
Diagnostic of Clostridioides difficile infections
No full textCilj istraživanja: Cilj istraživanja je opisati metode mikrobiološke dijagnostike C. difficile te istražiti mikrobiološke osobitosti toksigenih sojeva i demografske karakteristike pacijenata oboljelih od CDI u KBC-u Split od 1. siječnja do 31. prosinca 2020. godine.
Materijali i metode istraživanja: U ovom istraživanju korišteni su podatci Kliničkog zavoda za mikrobiologiju i parazitologiju KBC-a Split. Uključeni su svi pacijenti kojima je u navedenom razdoblju dokazan toksigeni soj C. difficile iz uzorka stolice. Mikrobiološka dijagnostika CDI provodi se prema smjernicama ESCMID-a prema tkz. dvostupanjskom i trostupanjskom dijagnostičkom postupniku. U ovom istraživanju je korišten kombinirani membranski imunoenzimski/ imunokromatografski test (Savyon Diagnostics Ltd.) koji istovremeno testira glutamat dehidrogenazu (GDH antigen) i proizvodnju toksina A i B C. difficile. Na taj način se istovremeno provode prvi i drugi korak preporučenog ESCMID-ovog postupnika za dijagnostiku CDI. . Kao potvrdni test, korišten je HG C. difficile molekularni test proizvođača HiberGene. Test koristi izotermalnu LAMP (engl. loop-mediated isothermal amplification) tehnologiju kojom se dokazuje prisustvo toksigene regije u genomu C. difficile.
Rezultati: U Kliničkom zavodu za mikrobiologiju i parazitologiju Kliničkog bolničkog centra Split u 2020. godini pod sumnjom na C. difficile infekciju zaprimljeno je 1675 uzorka stolice. Od toga je 1265 bilo negativno, a u 397 (24 %) uzoraka dokazan je toksigeni soj C. difficile. Od ukupno 397 toksigenih sojeva C. difficile, 3 % je bilo pozitivno samo na proizvodnju toksina A, 5 % uzoraka je bilo pozitivno na proizvodnju toksina B, 65 % uzoraka je bilo pozitivno na proizvodnju toksina A i B, a 27 % toksigenih sojeva C. difficile nije stvaralo toksine u trenutku testiranja. Muškaraca je bilo 176 (44 %), dok je žena bilo 221 (56 %). Najveći broj pacijenata (66 %) je imao 65 ili više godina. Bolničkih pacijenata je bilo 72 %, a najveći broj njih je liječen u Klinici za unutarnje bolesti (34 %), Klinici za infektivne bolesti (16 %) te u Klinici za plućne bolesti (14 %). Najčešće uputne dijagnoze su crijevne infekcije (20 %), ostale bolesti probavnog sustava (23 %) te respiratorne bolesti (16 %).Aim of the study: The aim of this study is to describe the methods of microbiological diagnostic of C. difficile and to investigate the microbiological characteristics of toxigenic strains and demographic characteristics of patients with CDI in the University Hospital of Split from 1 January to 31 December 2020.
Materials and methods of the study: Data base of the Department of Clinical Microbiology and Parasitology in the University Hospital of Split was used in this study. All patients for whom a toxigenic strain of C. difficile from a stool sample was detected during this period were included. Microbiological diagnostic of CDI is carried out according to the guidelines of the ESCMID according to the so-called two-stage and three-stage diagnostic procedure. A combined membrane enzyme-linked immunosorbent assay/ immunochromatography test (Savyon Diagnostics Ltd.) was used in this study, which simultaneously tests glutamate dehydrogenase (GDH antigen) and the production of C. difficile toxins A and B. This way, the first and second step of the recommended ESCMID procedure for diagnosing CDI are performed simultaneously. As a confirmatory test, the HG C. difficile molecular test manufactured by HiberGene was used. The test uses loop-mediated isothermal amplification technology to prove the presence of a toxigenic region in the C. difficile genome.
Results: In 2020, 1675 stool samples were received at the Department of Clinical Microbiology and Parasitology in the Univeristy Hospital of Split under suspicion of C. difficile infection. Of these, 1265 were negative, and a toxigenic strain of C. difficile was detected in 397 (24 %) samples. Of a total of 397 toxic strains of C. difficile, 3 % were only positive for toxin A production, 5 % of samples were positive for toxin B production, 65 % of samples were positive for toxin A and B production, and 27 % of toxigenic C. difficile strains did not produce toxins at the time of testing. There were 176 men (44 %) and 221 women (56 %). The largest number of patients (66 %) were 65 or older. There were 72 % of hospital patients, and the largest number of them were treated in the Clinic for Internal Medicine (34 %), the Clinic for Infectious Diseases (16 %) and the Clinic for Lung Diseases (14 %). The most common diagnoses are intestinal infections (20 %), other diseases of the digestive system (23 %) and respiratory diseases (16 %)
Antitumor effect of the essential oil of the mastic tree (Pistacia lentiscus L.) on breast cancer cell lines
No full textCilj istraživanja: Cilj ovog istraživanja je ispitati potencijalno citotoksično i antitumorsko djelovanje eteričnog ulja izoliranog iz lista tršlje (Pistacia lentiscus L.). na dvije humane karcinomske stanične linije dojke – MDA-MB-231 i MCF-7. Pretpostavljeno je da će se broj karcinomskih stanica smanjiti nakon izlaganja određenim koncentracijama eteričnog ulja tršlje u usporedbi s kontrolnom skupinom.
Materijali i metode: Kako bi izmjerili postotak preživjelih stanica tj. staničnu metaboličku aktivnost, korišten je neradioaktivni kolorimetrijski MTT testni sustav koji se zasniva na redukciji žute tetrazolijeve soli u ljubičaste kristale formazana pomoću metabolički aktivnih stanica. Eterična ulja su se inkubirala u rasponu koncentracija od 1 do 500 µg/mL tijekom 72 sata u tri replikata, a apsorbancija se mjerila na 570 nm na čitaču mikropločica nakon 24, 48 i 72 sata.
Rezultati: Rezultati ovog istraživanja nakon izlaganja karcinomskih stanica različitim koncentracijama eteričnog ulja biljke tršlje se razlikuju za pojedinu karcinomsku staničnu liniju dojke. Najznačajniji rezultati djelovanja na MDA-MB-231 staničnu liniju su nakon inkubacije od 48 sati pri koncentraciji od 500 µg/ml gdje se stanična viabilnost smanjila na 19 % te pri koncentraciji od 250 µg/ml nakon 24 sata gdje se stanična viabilnost smanjila na 52 %. Kod stanične linije MCF-7 najznačajniji rezultati su nakon inkubacije od 48 sati pri koncentraciji od 500 µg/ml gdje se stanična viabilnost smanjila na 30 % te pri koncentraciji od 500 µg/ml nakon 24 sata gdje se stanična viabilnost smanjila na 36 %.
Zaključak: Temeljem dobivenih rezultata ovog istraživanja zaključujemo da eterično ulje lista tršlje ima potencijal u liječenju karcinoma dojke te da u određenom postotku ubija karcinomske stanice. U odnosu na staničnu liniju MDA-MB-231, eterično ulje lista tršlje pokazuje slabije citotoksično djelovanje na staničnu liniju MCF-7. IC50 vrijednost je postignuta za obe stanične linije te se ona smanjuje s povećanjem trajanja inkubacije. Vrijednost je niža kod MDA-MB-231 stanične linije u odnosu na MCF-7 staničnu liniju.Aim of the study: The aim of this research is to examine the potential cytotoxic and antitumor effect of the essential oil isolated from the leaves of the Pistacia lentiscus L. plant on two human breast cancer cell lines - MDA-MB-231 and MCF-7. It was hypothesized that the number of cancer cells will decrease after exposure to certain concentrations of essential oil of mastic tree compared to the control group.
Materials and methods: In order to measure the percentage of surviving cells, i.e. cellular metabolic activity, a non-radioactive colorimetric MTT test system was used, which is based on the reduction of yellow tetrazolium salt into purple formazan crystals by metabolically active cells. Essential oils were incubated in the concentration range from 1 to 500 µg/mL for 72 hours in three replicates, and the absorbance was measured at 570 nm on a microplate reader after 24, 48 and 72 hours. Results: The results of this research after exposure of cancer cells to different concentrations of the essential oil of the mastic tree differ for each breast cancer cell line. The most significant results of the effect on the MDA-MB-231 cell line are after incubation for 48 hours at a concentration of 500 µg/ml where cell viability decreased to 19% and at a concentration of 250 µg/ml after 24 hours where cell viability decreased to 52 %. In the case of the MCF-7 cell line, the most significant results were obtained after incubation for 48 hours at a concentration of 500 µg/ml, where cell viability decreased to 30%, and at a concentration of 500 µg/ml after 24 hours, where cell viability decreased to 36%.
Conclusion: Based on the results of this research, we conclude that the essential oil of the Pistacia Lentiscus L. leaf has potential in the treatment of breast cancer and that it kills cancer cells in a certain percentage. Compared to the MDA-MB-231 cell line, mastic tree leaf extracts show a weaker cytotoxic effect on the MCF-7 cell line. The IC50 value was reached for both cell lines and it decreases with increasing incubation time. The value is lower in MDA-MB-231 cell line compared to MCF-7 cell line
Antitumor effect of the essential oil of the mastic tree (Pistacia lentiscus L.) on breast cancer cell lines
No full textCilj istraživanja: Cilj ovog istraživanja je ispitati potencijalno citotoksično i antitumorsko djelovanje eteričnog ulja izoliranog iz lista tršlje (Pistacia lentiscus L.). na dvije humane karcinomske stanične linije dojke – MDA-MB-231 i MCF-7. Pretpostavljeno je da će se broj karcinomskih stanica smanjiti nakon izlaganja određenim koncentracijama eteričnog ulja tršlje u usporedbi s kontrolnom skupinom.
Materijali i metode: Kako bi izmjerili postotak preživjelih stanica tj. staničnu metaboličku aktivnost, korišten je neradioaktivni kolorimetrijski MTT testni sustav koji se zasniva na redukciji žute tetrazolijeve soli u ljubičaste kristale formazana pomoću metabolički aktivnih stanica. Eterična ulja su se inkubirala u rasponu koncentracija od 1 do 500 µg/mL tijekom 72 sata u tri replikata, a apsorbancija se mjerila na 570 nm na čitaču mikropločica nakon 24, 48 i 72 sata.
Rezultati: Rezultati ovog istraživanja nakon izlaganja karcinomskih stanica različitim koncentracijama eteričnog ulja biljke tršlje se razlikuju za pojedinu karcinomsku staničnu liniju dojke. Najznačajniji rezultati djelovanja na MDA-MB-231 staničnu liniju su nakon inkubacije od 48 sati pri koncentraciji od 500 µg/ml gdje se stanična viabilnost smanjila na 19 % te pri koncentraciji od 250 µg/ml nakon 24 sata gdje se stanična viabilnost smanjila na 52 %. Kod stanične linije MCF-7 najznačajniji rezultati su nakon inkubacije od 48 sati pri koncentraciji od 500 µg/ml gdje se stanična viabilnost smanjila na 30 % te pri koncentraciji od 500 µg/ml nakon 24 sata gdje se stanična viabilnost smanjila na 36 %.
Zaključak: Temeljem dobivenih rezultata ovog istraživanja zaključujemo da eterično ulje lista tršlje ima potencijal u liječenju karcinoma dojke te da u određenom postotku ubija karcinomske stanice. U odnosu na staničnu liniju MDA-MB-231, eterično ulje lista tršlje pokazuje slabije citotoksično djelovanje na staničnu liniju MCF-7. IC50 vrijednost je postignuta za obe stanične linije te se ona smanjuje s povećanjem trajanja inkubacije. Vrijednost je niža kod MDA-MB-231 stanične linije u odnosu na MCF-7 staničnu liniju.Aim of the study: The aim of this research is to examine the potential cytotoxic and antitumor effect of the essential oil isolated from the leaves of the Pistacia lentiscus L. plant on two human breast cancer cell lines - MDA-MB-231 and MCF-7. It was hypothesized that the number of cancer cells will decrease after exposure to certain concentrations of essential oil of mastic tree compared to the control group.
Materials and methods: In order to measure the percentage of surviving cells, i.e. cellular metabolic activity, a non-radioactive colorimetric MTT test system was used, which is based on the reduction of yellow tetrazolium salt into purple formazan crystals by metabolically active cells. Essential oils were incubated in the concentration range from 1 to 500 µg/mL for 72 hours in three replicates, and the absorbance was measured at 570 nm on a microplate reader after 24, 48 and 72 hours. Results: The results of this research after exposure of cancer cells to different concentrations of the essential oil of the mastic tree differ for each breast cancer cell line. The most significant results of the effect on the MDA-MB-231 cell line are after incubation for 48 hours at a concentration of 500 µg/ml where cell viability decreased to 19% and at a concentration of 250 µg/ml after 24 hours where cell viability decreased to 52 %. In the case of the MCF-7 cell line, the most significant results were obtained after incubation for 48 hours at a concentration of 500 µg/ml, where cell viability decreased to 30%, and at a concentration of 500 µg/ml after 24 hours, where cell viability decreased to 36%.
Conclusion: Based on the results of this research, we conclude that the essential oil of the Pistacia Lentiscus L. leaf has potential in the treatment of breast cancer and that it kills cancer cells in a certain percentage. Compared to the MDA-MB-231 cell line, mastic tree leaf extracts show a weaker cytotoxic effect on the MCF-7 cell line. The IC50 value was reached for both cell lines and it decreases with increasing incubation time. The value is lower in MDA-MB-231 cell line compared to MCF-7 cell line
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
- …
