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2021 ◽  
Vol 13 (1) ◽  
pp. 17-29
Author(s):  
Emann M Rabie ◽  
Sherry X Zhang ◽  
Andreas P Kourouklis ◽  
A Nihan Kilinc ◽  
Allison K Simi ◽  
...  

Abstract Metastasis, the leading cause of mortality in cancer patients, depends upon the ability of cancer cells to invade into the extracellular matrix that surrounds the primary tumor and to escape into the vasculature. To investigate the features of the microenvironment that regulate invasion and escape, we generated solid microtumors of MDA-MB-231 human breast carcinoma cells within gels of type I collagen. The microtumors were formed at defined distances adjacent to an empty cavity, which served as an artificial vessel into which the constituent tumor cells could escape. To define the relative contributions of matrix degradation and cell proliferation on invasion and escape, we used pharmacological approaches to block the activity of matrix metalloproteinases (MMPs) or to arrest the cell cycle. We found that blocking MMP activity prevents both invasion and escape of the breast cancer cells. Surprisingly, blocking proliferation increases the rate of invasion but has no effect on that of escape. We found that arresting the cell cycle increases the expression of MMPs, consistent with the increased rate of invasion. To gain additional insight into the role of cell proliferation in the invasion process, we generated microtumors from cells that express the fluorescent ubiquitination-based cell cycle indicator. We found that the cells that initiate invasions are preferentially quiescent, whereas cell proliferation is associated with the extension of invasions. These data suggest that matrix degradation and cell proliferation are coupled during the invasion and escape of human breast cancer cells and highlight the critical role of matrix proteolysis in governing tumor phenotype.


2020 ◽  
pp. 66-68
Author(s):  
Gunel Rubail ghizy Nasibova

In studies, carried out in different climatic zones in the age groups of turkeys, it was found that the rate of invasion extensiveness of turkeys with the causative agents of A. dissimilis, H. gallinarum, and R. tetragona in the foothill zones was relatively high, in comparison with the mountainous and low-lying zones. The invasion intensity was observed in turkey chicks at the two-three months of age.


2017 ◽  
Author(s):  
Peter Hristov ◽  
Any Georgieva ◽  
Georgi Radoslavov ◽  
Daniela Sirakova ◽  
Gyulnas Dzhebir ◽  
...  

Nosema apis and Nosema ceranae are the two main microsporidian parasites causing nosematosis in honey bee Apis mellifera. The object of the present study is to investigate the presence of Nosema apis and Nosema ceranae in the Bulgarian honey bee. The 16S (SSU) rDNA gene region was chosen for analysis. A duplex PCR assay was performed on 108 honey bee samples from three different parts of the country (South, North and West Bulgaria). The results showed that the samples from the northern part of the country were with the highest rate of invasion (77.2%) for Nosema ceranae while those from the mountainous parts (the Rodopa Mountains, South Bulgaria) were with the lowest rate (13.9%). Infection with Nosema apis alone and co-infection N. apis/N. ceranae were not detected in any samples. These findings suggest that Nosema ceranae is the dominant species in the Bulgarian honey bee. It is not known when the introduction of Nosema ceranae in Bulgaria has occurred, but like in the rest of the world, this species has become the dominant one in Bulgarian Apis mellifera. In conclusion, this is the first report for molecular detection of Nosema infection in Bulgarian honey bee that confirms the worldwide dissemination and prevalence of Nosema ceranae.


2017 ◽  
Author(s):  
Peter Hristov ◽  
Any Georgieva ◽  
Georgi Radoslavov ◽  
Daniela Sirakova ◽  
Gyulnas Dzhebir ◽  
...  

Nosema apis and Nosema ceranae are the two main microsporidian parasites causing nosematosis in honey bee Apis mellifera. The object of the present study is to investigate the presence of Nosema apis and Nosema ceranae in the Bulgarian honey bee. The 16S (SSU) rDNA gene region was chosen for analysis. A duplex PCR assay was performed on 108 honey bee samples from three different parts of the country (South, North and West Bulgaria). The results showed that the samples from the northern part of the country were with the highest rate of invasion (77.2%) for Nosema ceranae while those from the mountainous parts (the Rodopa Mountains, South Bulgaria) were with the lowest rate (13.9%). Infection with Nosema apis alone and co-infection N. apis/N. ceranae were not detected in any samples. These findings suggest that Nosema ceranae is the dominant species in the Bulgarian honey bee. It is not known when the introduction of Nosema ceranae in Bulgaria has occurred, but like in the rest of the world, this species has become the dominant one in Bulgarian Apis mellifera. In conclusion, this is the first report for molecular detection of Nosema infection in Bulgarian honey bee that confirms the worldwide dissemination and prevalence of Nosema ceranae.


2017 ◽  
Vol 474 (19) ◽  
pp. 3227-3240 ◽  
Author(s):  
Christopher J. Clarke ◽  
Stephane R. Gross ◽  
Thamir M. Ismail ◽  
Philip S. Rudland ◽  
Morteta Al-Medhtiy ◽  
...  

S100P protein in human breast cancer cells is associated with reduced patient survival and, in a model system of metastasis, it confers a metastatic phenotype upon benign mammary tumour cells. S100P protein possesses a C-terminal lysine residue. Using a multiwell in vitro assay, S100P is now shown for the first time to exhibit a strong, C-terminal lysine-dependent activation of tissue plasminogen activator (tPA), but not of urokinase-catalysed plasminogen activation. The presence of 10 μM calcium ions stimulates tPA activation of plasminogen 2-fold in an S100P-dependent manner. S100P physically interacts with both plasminogen and tPA in vitro, but not with urokinase. Cells constitutively expressing S100P exhibit detectable S100P protein on the cell surface, and S100P-containing cells show enhanced activation of plasminogen compared with S100P-negative control cells. S100P shows C-terminal lysine-dependent enhancement of cell invasion. An S100P antibody, when added to the culture medium, reduced the rate of invasion of wild-type S100P-expressing cells, but not of cells expressing mutant S100P proteins lacking the C-terminal lysine, suggesting that S100P functions outside the cell. The protease inhibitors, aprotinin or α-2-antiplasmin, reduced the invasion of S100P-expressing cells, but not of S100P-negative control cells, nor cells expressing S100P protein lacking the C-terminal lysine. It is proposed that activation of tPA via the C-terminal lysine of S100P contributes to the enhancement of cell invasion by S100P and thus potentially to its metastasis-promoting activity.


2017 ◽  
Vol 19 (78) ◽  
pp. 118-120
Author(s):  
M.M. Danko ◽  
O.L. Tishyn ◽  
R.V. Khomiak ◽  
Zh.M. Perih

The article presents data on the effectiveness of two fenbendazole-based drugs for oral application: «Feboral» (in the form of a solution) and «Brovadazol 20%» (the reference drug in the form of powder). For this purpose, 420-day-old chickens were examined by a flotation coproscopic method in order to detect intestinal invasions. The therapeutic efficacy of the drugs was determined according to the data of the coproscopic examinations carried out using the modified quantitative McMaster counting method. The study of the efficacy of «Febboral» and «Brovadazol 20%» preparations was performed under the conditions of vivarium of the State scientific-research control institute of  veterinary medicinal products and feed additives.During the experiment birds of experimental groups used preparations on the basis of fenbendazole: hens of the first experimental group, the drug «Feboral» was poured out with water (1.0 ml of the preparation for 10 kg of b. w., twice for two days), the second – the drug «Brovadazol 20%» they were given with food (0.5 g of the preparation at 10 kg b. w., for five days). Birds in the control group were given water and food without the contents of drugs.According to the results of research in hens were found invasion by Heterakis galinarum. The average rate of invasion of hens by nematodes during treatment with drugs was 176 eggs per 1 g of litter. In the hens of the first and second experimental groups, the average intensity of the helminth infestation on the seventh day of the experiment was 84.5 eggs per 1 g of litter, while the intensity of the infection of the control group was 211 eggs per 1 g of litter. On the fourteenth day of the experiment, the excretion of eggs from the pathogen in the hens of both experimental groups was not noted, while in the hens of the control group, the intensity of the invasion amounted to 238 eggs heterakis in 1 gram of litter.Consequently, the extenseffectivity of the drug «Febboral» and the reference drug «Brovadazol 20%» for heterakoses of chickens was 100%. 


2015 ◽  
Vol 24 (3) ◽  
pp. eR01 ◽  
Author(s):  
Peter Thomas ◽  
Xavier Garcia-Marti

<p><em>Aim of study:</em><strong> </strong>Being the longest-lived of all European trees, capable of living significantly over 2,000 years, yew is highly likely to be negatively affected by climate change; this paper explores the changes in distribution and abundance. </p><p><em>Main results:</em> Yew is unlikely to migrate north due to its slow rate of invasion, its disjunct soil needs and an inability to cope with the expected rate of climate change. It will, however, retreat from the southern end of its range in Spain due to increased evapotranspiration allied to reduced rainfall. In the south, increased drought will be exacerbated by extreme drought and increased fire frequency. In drier areas at the northern edge of its range, yew will decline where growing on well-drained limestone outcrops with little shelter from the sun (increased evaporation) and reduced water availability due to limited root spread.  On wetter northern sites, yew should find better climatic conditions but will be slow to invade new areas due to poorer reproduction affected by reduced pollen production, population fragmentation and limited seed movement. Overall, without our intervention, yew will survive by inertia in the short-term but eventual become extinct in most areas. Of equal concern will be the loss of old veteran individuals and associated biodiversity. </p><p><em>Research highlights:</em> There is an urgent need for interventionist management for both old and young trees, relieving the stress on old veteran trees, and planting and maintaining seedlings through vulnerable young age. A list of management priorities is given.</p><p><strong>Keywords: </strong>Yew; <em>Taxus baccata</em>; Temperature; Precipitation; Seedlings; Bioclimate envelope; Species range.</p>


2015 ◽  
Vol 122 (4) ◽  
pp. 803-811 ◽  
Author(s):  
Alexander S. G. Micko ◽  
Adelheid Wöhrer ◽  
Stefan Wolfsberger ◽  
Engelbert Knosp

OBJECT An important prognostic factor for the surgical outcome and recurrence of a pituitary adenoma is its invasiveness into parasellar tissue, particularly into the space of the cavernous sinus (CS). The aims of this study were to reevaluate the existing parasellar classifications using an endoscopic technique and to evaluate the clinical and radiological outcomes associated with each grade. METHODS The authors investigated 137 pituitary macroadenomas classified radiologically at least on one side as Grade 1 or higher (parasellar extension) and correlated the surgical findings using an endoscopic technique, with special reference to the invasiveness of the tumor into the CS. In each case, postoperative MRI was performed to evaluate the gross-total resection (GTR) rate and the rate of endocrinological remission (ER) in functioning adenomas. RESULTS The authors found a 16% rate of CS invasion during surgery for these macroadenomas. Adenomas radiologically classified as Grade 1 were found to be invasive in 1.5%, and the GTR/ER rate was 83%/88%. For Grade 2 adenomas, the rate of invasion was 9.9%, and the GTR/ER rate was 71%/60%. For Grade 3 adenomas, the rate of invasion was 37.9%, and the GTR/ER rate was 75%/33%. When the superior compartment of the CS (Grade 3A) was involved, the authors found a rate of invasion that was lower (p < 0.001) than that when the inferior compartment was involved (Grade 3B). The rate of invasion in Grade 3A adenomas was 26.5% with a GTR/ER rate of 85%/67%, whereas for Grade 3B adenomas, the rate of surgically observed invasion was 70.6% with a GTR/ER rate of 64%/0%. All of the Grade 4 adenomas were invasive, and the GTR/ER rate was 0%. A comparison of microscopic and endoscopic techniques revealed no difference in adenomas with Grade 1 or 4 parasellar extension. In Grade 2 adenomas, however, the CS was found by the endoscopic technique to be invaded in 9.9% and by microscopic evaluation to be invaded in 88% (p < 0.001); in Grade 3 adenomas, the difference was 37.9% versus 86%, respectively (p = 0.002). Grade 4 adenomas had a statistically significant lower rate of GTR than those of all the other grades. In case of ER only, Grade 1 adenomas had a statistically significant higher rate of remission than did Grade 3B and Grade 4 adenomas. CONCLUSIONS The proposed classification proved that with increasing grades, the likelihood of surgically observed invasion rises and the chance of GTR and ER decreases. The direct endoscopic view confirmed the low rate of invasion of Grade 1 adenomas but showed significantly lower rates of invasion in Grade 2 and 3 adenomas than those previously found using the microscopic technique. In cases in which the intracavernous internal carotid artery was encased (Grade 4), all the adenomas were invasive and the GTR/ER rate was 0%/0%. The authors suggest the addition of Grades 3A and 3B to distinguish the strikingly different outcomes of adenomas invading the superior CS compartments and those invading the inferior CS compartments.


2014 ◽  
Vol 17 (2) ◽  
pp. 361-363 ◽  
Author(s):  
J. Ziętek ◽  
Ł. Adaszek ◽  
B. Dzięgiel ◽  
M. Kalinowski ◽  
M. Bartnicki ◽  
...  

AbstractThe purpose of the study was the in vivo diagnosing of E. cuniculi invasions in pet rabbits with neurological symptoms using the Real-Time PCR, and determination of the rate of invasion, in this group of animals. The study involved 103 pet rabbits with neurological symptoms. Parasitic invasions were diagnosed using Real-Time PCR. The DNA of the parasites for molecular tests was isolated from the urine of the diseased animals. Out of the 103 tested DNA samples, the presence of the E. cuniculi genetic material was detected in 27 samples (26.21%). The melting temperature (Tm) of all products was 77.5oC. The presence of parasitic DNA in the urine of 26.21% of examined animals indicates that E. cuniculi infections occur widely in pet rabbits in Poland and are a significant cause of neurological disorders in those animals


2013 ◽  
Vol 50 (2) ◽  
pp. 510-518 ◽  
Author(s):  
Nicholas H. Ogden ◽  
L. Robbin Lindsay ◽  
Patrick A. Leighton

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