1,721,031 research outputs found
What You Eat Matters: Nutrient Inputs Alter the Metabolism and Neuropeptide Expression in Egyptian Cotton Leaf Worm, Spodoptera littoralis (Lepidoptera: Noctuidae)
No full textLipids and carbohydrates are the two primary energy sources for both animals and insects. Energy homeostasis is under strict control by the neuroendocrine system, and disruption of energy homeostasis leads to the development of various disorders, such as obesity, diabetes, fatty liver syndrome, and cardiac dysfunction. One critical factor in this respect is feeding habits and diet composition. Insects are good models to study the physiological and biochemical background of the effect of diet on energy homeostasis and related disorders; however, most studies are based on a single model species, Drosophila melanogaster. In the current study, we examined the effects of four different diets, high fat (HFD), high sugar (HSD), calcium-rich (CRD), and a plant-based (PBD) on energy homeostasis in younger (third instar) and older (fifth instar) larvae of the Egyptian cotton leafworm, Spodoptera littoralis (Lepidoptera: Noctuidae) in comparison to a regular artificial bean diet. Both HSD and HFD led to weight gain, while CRD had the opposite effect and PBD had no effect in fifth instar larvae and pupae. The pattern was the same for HSD and CRD in third instar larvae while a reduction in weight was detected with HFD and PBD. Larval development was shortest with the HSD, while HFD, CRD, and PBD led to retardation compared to the control. Triglyceride (TG) levels were higher with HFD, HSD, and PBD, with larger lipid droplet sizes, while CRD led to a reduction of TG levels and lipid droplet size. Trehalose levels were highest with HSD, while CRD led to a reduction at third instar larvae, and HFD and PBD had no effect. Fifth instar larvae had similar levels of trehalose with all diets. There was no difference in the expression of the genes encoding neuropeptides SpoliAKH and SpoliILP1-2 with different diets in third instar larvae, while all three genes were expressed primarily with HSD, and SpolisNPF was primarily expressed with HFD in fifth instar larvae. In summary, different diet treatments alter the development of insects, and energy and metabolic pathways through the regulation of peptide hormones
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Investigating the therapeutic effects of human umbilical cord derived mesenchymal stromal stem cells in tissue repair after myocardial ischemia in rats
No full textMiyokard infarktüsü (Mİ) mortalitesi ve morbiditesi oldukça yüksek olan yaygın bir sağlık problemidir. Güncel farmakolojik ve girişimsel tedavi yaklaşımları sağ kalımı ve hastanın yaşam kalitesini artırmakla birlikte temel sorun olan kardiyak doku kaybını düzeltememektedir. Bu temel sorunun çözümüne yönelik Mİ tedavi uygulamalarında, rejeneratif özellikleri nedeniyle, kök hücreler hedef haline gelmiştir. Mİ tedavisinde kemik iliği mezenkimal kök hücreleri başta olmak üzere, iskelet kası miyoblastları, adipoz doku mezenkimal kök hücreleri, embriyonik kök hücreler, uyarılmış pluripotent kök hücreler, kardiyak kök hücreler gibi çok sayıda farklı kök hücre tipi denenmiştir ve denenmektedir. Bir tür multipotent kök hücre olan göbek kordonu stroması mezenkimal kök hücrelerinin, farklılaşma potensileri, elde edilmelerindeki ve kullanımlarındaki kolaylıklar, immün modülasyon gibi, tedavide diğer kök hücrelere göre üstün kabul edilebilecek özellikleri nedeniyle bu çalışmamızda sıçan Mİ modellerinde insan göbek kordonu stroması mezenkimal kök hücrelerinin tedavi edici etkisi araştırıldı. Deney modeli oluşturmak için sağlıklı 32 adet sekiz haftalık, 200-250 g ağırlığında, erkek, Wistar türü albino sıçanlar kullanıldı. Mİ oluşturmak üzere LAD koroner arteri orta kısmından kalıcı olarak bağlanan sıçanlar rastgele, PBS ve iGKS-MKH tedavisi verilen deney grupları olmak üzere iki gruba ayrıldı. Mİ, miyokardiyumdaki bölgesel soluklaşma ve hareket bozukluğu ile görsel olarak teyit edilir edilmez, PBS grubu sıçanlara sadece 250 L PBS, iGKS-MKH grubuna ise yeşil flüoresan etkinliğe sahip calcein AM ile işaretlenerek 250 L PBS içerisinde süspanse edilmiş 2,2 × 106 iGKS-MKH intramiyokardiyal enjeksiyon yapılarak uygulandı. PBS grubundan yaşayan 8 adet sıçan ve iGKS-MKH grubundan yaşayan 8 adet sıçan, Mİ ve PBS ya da hücre uygulamasını takip eden 3. haftada sakrifiye edildi. Sakrifikasyondan önce PBS grubundan 6, iGKS-MKH grubundan 3 sıçana EKO değerlendirmesi yapıldı. Kalp fonksiyonlarının değerlendirilmesi için yapılan EKO incelemesinde LVEDD, LVEF parametreleri ölçüldü ve duvar hareket anormallikleri değerlendirildi. Sakrifikasyonu takiben PBS grubundan 4, iGKS-MKH grubundan 7 sıçanın kalbi TTC ile boyandıktan sonra dilimlenerek fotoğraflandı ve Image J bilgisayar programı yardımı ile 100 × infarkt alan/tüm alan eşitliği ile infarkt alanları oransal olarak hesaplandı. Toplanan tüm kalp dokularının seri frozen kesitleri alındıktan sonra, belli aralıklarla bu kesitlerden bir kısmına trikrom boyaması yapıldı ve ardından ışık mikroskobu altında fibrotik alanlar değerlendirildi. Ayrıca hücre tedavisi uygulanan gruptan hayvanların kalp dokusu seri frozen kesitlerinde, nakilden önce calcein AM ile işaretlenmiş iGKS-MKH'nin varlığı, yeşil calcein sinyali ya da insana özgü antijenlerle etkileşen anti-lamin A+C antikoru kullanılarak araştırıldı. Bunun yanı sıra kardiyomiyojenik farklılaşmayı tespit edebilmek için yine seri frozen kesitlerde alfa sarkomerik aktin ve sadece insana özgü antijenlerle etkileşen kardiyak troponin I antikorlarıyla işaretlemeler yapılarak kesitler konfokal mikroskopta incelendi. EKO değerlendirmesi sonucunda, PBS grubuyla karşılaştırıldığında, iGKS-MKH grubunun LVEF değerinin belirgin olarak iyileştiğinin (p=0,037) tespit edilmesi; yine PBS grubunun sol ventrikülünde akinezi izlenirken iGKS-MKH grubunda ise hipokinezi tespit edilmesi hücresel tedaviyle sağlanan fonksiyonel iyileşme lehine bulgulardır. İnfarkt alanı ölçümlerine göre, Mİ ve hücre uygulamasından 3 hafta sonra yapılan değerlendirmede, iGKS-MKH grubunda infarkt alanının PBS grubununkine göre belirgin olarak azaldığı ve bu azalmanın anlamlı olduğu tespit edildi (p=0,006). Kalp kesitlerinin TK boyalı preparasyonlarında, PBS kontrol grubunda fibrotik alanların daha yaygın olduğu ve bu alanların da yoğun kollajen ağı içerdiği gözlendi. Hücre ile tedavi edilen gruplarda ise, fibrotik alanların daha sınırlı olduğu ve PBS kontrol grubu ile karşılaştırıldığında bu alanların kollajen liflerin yanı sıra hücreden ve vasküler yapılardan daha zengin olduğu tespit edildi. TK prosedürü uygulanan kesitlerin diğer serileri konfokal mikroskopta incelendiğinde ise, çoğunlukla fibrotik alanda olmak üzere yer yer de fibrozise komşu alanlarda yeşil sinyal pozitifliği gösteren hücreler tespit edildi. Nakil öncesinde calcein AM ile işaretlenen hücreler olduğu düşünülen bu hücreler ileri analiz edildiğinde, bir kısmının insana özgü antijenlerle etkileşen kardiyak troponin I pozitifliği gösterdiği ve yine bu hücrelerin alfa sarkomerik aktin açısından da pozitif olduğu tespit edildi. Tüm bu veriler birlikte ele alındığında, iGKS-MKH ile tedavinin, Mİ sonrasında infarkt boyutlarını azalttığı, miyokardiyal faklılaşma göstererek onarım sürecine katıldığı ve kalp fonksiyonlarında iyileşmeye katkıda bulunduğu söylenebilir.Myocardial infarction (MI) is a worlwide health problem with a high mortality and morbidity. Current pharmacological and interventional treatment approaches increases survey and improves life quality of patient, but fails to prevent cardiac tissue loss that constitute essential problem of MI. In the treatment applications of MI as an approach for solution of this essential problem, stem cells have been under the focus because of their regenerative characteristics. In treatment of MI, primarily bone marrow mesenchymal stem cells and number of various stem cell types have been experienced such as skeleton muscles myoblasts, adipose tissue mesenchymal stem cells, embryonic stem cells, induced pluripotent stem cells and cardiac stem cells. In the present study, due to their characteristics, which can be considered as superiority in treatment compared to the other stems cells such as convenience in their isolation and usage, differentiation potency and immune modulation, we investigated the therapeutic effects of human umbilical cord stroma derived mesenchymal stem cells (hUC-MSC), a kind of multipotent stem cell, in the rat MI model. In order to create an experimental MI model, 32 healthy, 8-week old, weighing 200-250 g, male Wistar albino rats were used in this study. MI is carried out by a permanent ligation of LAD coronary artery at middle portion and confirmed visually by direct observation of regional myocardial paleness and disruption in contractility. Then, rats were randomly assigned to two groups as PBS group and hUC-MSC treatment group. PBS group was injected only with 250 L PBS into the infarct border zone, whereas the hUC-MSC group was injected with 2,2 × 106 hUC-MSC suspended in 250 L PBS, intramyocardially into the infarct border zone. Before transplantation, hUC-MSC was labeled with calcein AM, a green fluorescent molecule. Eight surviving rats from each PBS and the hUC-MSC groups were sacrificed at 3rd weeks after MI and PBS or cell transplantation. Before the rats were sacrificed, 6 rats from the PBS group and 3 rats from the hUC-MSC group were taken into echocardiographic examination for the evaluation of heart functions. By the echocardiographic examination, left ventricle end diastolic diameter (LVEDD) and left ventricle ejection fraction (LVEF) was calculated and wall motion abnormalities were evaluated. After the rats were sacrificed, hearts of 4 rats from the PBS group and 7 rats from the hUC-MSC group were stained with triphenyl tetrazolium chloride (TTC), and sliced to be observed microscopically. By using Image J Software, infarcted areas were calculated proportionally based on 100 × infarcted area/all areas on photographed heart slice. After getting frozen cross-sections series of all harvested heart tissues, some of these sections with a determined interval were stained with trichrome for evaluation of fibrotic areas using light microscope. Moreover, in serial frozen cross-sections of heart tissues of animals from the cell treatment group, existence of the hUC-MSC transplanted after the incubation with calcein AM was investigated by either using green calcein signal or using human-specific anti-lamin A+C antibody. Additionally, to identify the cardiomyogenic differentiation of these cells, serial frozen cross-sections were incubated with α-sarcomeric actin and human-specific cardiac troponin I antibodies and then examined in the confocal microscope. As a result of the echocardiographic evaluation, it was determined that the hUC-MSC group's LVEF value has improved remarkably in comparison with the PBS group (p=0,037); whereas akinesia of the PBS group persisted on the left ventricles. Hypokinesia was determined in the hUC-MSC group; these observations suggest that there has been functional recovery through cellular treatment. According to the measurements of the infarcted area, evaluated 3 weeks after the MI induction and cell transplantation, it was determined that infarct area in the hUC-MSC group was notably reduced in comparison with the PBS group and this reduction was found statistically significant (p=0,006). By the evaluation of trichrome stained preparations of the heart cross-sections, it was observed that fibrotic areas in the PBS control group were more extensive, and these areas were found containing dense collagen network. Concerning the group administered cell treatment, it was determined that fibrotic areas were more limited; and when it is compared with the PBS control group, these areas were found rich in cell and vascular structures as well as collagen fibers. When other cross-sections that consecutive series of trichrome stained sections, are examined on the confocal microscope, there were cells, exhibiting green-signal positivity, determined in mostly fibrotic areas as well as partly in the fibrosis-neighboring areas. When these cells, that are considered as the ones labeled with the calcein AM before the transplantation, are further analyzed, it was determined that a part of them were expressing human specific cardiac troponin I; and again that these cells were positive for α-sarcomeric actin too. Taken together, it can be concluded that the treatment of hUC-MSC has reduced infarct size after the MI, contributed in regenerative process by exhibiting myocardial differentiation and contributed in improvement of heart functions
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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