54 results on '"Jakubczak, P."'
Search Results
2. Raccoon dog (Nyctereutes procyonoides) phylogeography including the Polish population: local and global aspects
- Author
-
Horecka, B., Jakubczak, A., Ślaska, B., and Jeżewska-Witkowska, G.
- Abstract
AbstractThe raccoon dog (Nyctereutes procyonoides)is a representative of Canidae and is closely related to red fox-like canids, although the species exhibits high distinctiveness in the family. These animals were farmed for fur products, but thousands were intentionally released into the wild in western Russia. This newly established alien species in Europe has spread rapidly into many European countries. The aim of the study was to determine the origin of Polish populations by comparing the mitochondrial molecular marker cytochrome b (cytb) sequences of Polish wild and farm individuals with wild raccoon dogs from the western Russia and Asian specimens whose sequences were obtained from GenBank resources. The results of our phylogenetic analysis support the previous suggestions on the existence of two main clades clearly referring to continental and Island populations. Polish individuals were classified into a highly diverse continental group. The relationships between the haplotypes within the clade together with estimated values of genetic diversity parameters indicate that the Polish raccoon dog populations exhibit high genetic similarity to the Russian population. In combination with the history of introduction of the species to Europe, this suggests the most probable assignment of the Polish populations to the subspecies N. procyonoides ussuriensis. Our results indicate the presence of two Japanese haplotypes within the continental group, which is inconsistent with the assumed scenario of post-glacial expansion of raccoon dogs excluding gene flow between continental and Island populations.
- Published
- 2022
- Full Text
- View/download PDF
3. Corrections to Design of Selective, ATP-Competitive Inhibitors of Akt
- Author
-
Freeman-Cook, Kevin D., Autry, Christopher, Borzillo, Gary, Gordon, Deborah, Barbacci-Tobin, Elsa, Bernardo, Vincent, Briere, David, Clark, Tracey, Corbett, Matthew, Jakubczak, John, Kakar, Shefali, Knauth, Elizabeth, Lippa, Blaise, Luzzio, Michael J., Mansour, Mahmoud, Martinelli, Gary, Marx, Matthew, Nelson, Kendra, Pandit, Jayvardhan, Rajamohan, Francis, Robinson, Shaughnessy, Subramanyam, Chakrapani, Wei, Liuqing, Wythes, Martin, and Morris, Joel
- Published
- 2024
- Full Text
- View/download PDF
4. Tail-propelled aquatic locomotion in a theropod dinosaur
- Author
-
Ibrahim, Nizar, Maganuco, Simone, Dal Sasso, Cristiano, Fabbri, Matteo, Auditore, Marco, Bindellini, Gabriele, Martill, David M., Zouhri, Samir, Mattarelli, Diego A., Unwin, David M., Wiemann, Jasmina, Bonadonna, Davide, Amane, Ayoub, Jakubczak, Juliana, Joger, Ulrich, Lauder, George V., and Pierce, Stephanie E.
- Abstract
In recent decades, intensive research on non-avian dinosaurs has strongly suggested that these animals were restricted to terrestrial environments1. Historical proposals that some groups, such as sauropods and hadrosaurs, lived in aquatic environments2,3were abandoned decades ago4–6. It has recently been argued that at least some of the spinosaurids—an unusual group of large-bodied theropods of the Cretaceous era—were semi-aquatic7,8, but this idea has been challenged on anatomical, biomechanical and taphonomic grounds, and remains controversial9–11. Here we present unambiguous evidence for an aquatic propulsive structure in a dinosaur, the giant theropod Spinosaurus aegyptiacus7,12. This dinosaur has a tail with an unexpected and unique shape that consists of extremely tall neural spines and elongate chevrons, which forms a large, flexible fin-like organ capable of extensive lateral excursion. Using a robotic flapping apparatus to measure undulatory forces in physical models of different tail shapes, we show that the tail shape of Spinosaurusproduces greater thrust and efficiency in water than the tail shapes of terrestrial dinosaurs and that these measures of performance are more comparable to those of extant aquatic vertebrates that use vertically expanded tails to generate forward propulsion while swimming. These results are consistent with the suite of adaptations for an aquatic lifestyle and piscivorous diet that have previously been documented for Spinosaurus7,13,14. Although developed to a lesser degree, aquatic adaptations are also found in other members of the spinosaurid clade15,16, which had a near-global distribution and a stratigraphic range of more than 50 million years14, pointing to a substantial invasion of aquatic environments by dinosaurs.
- Published
- 2020
- Full Text
- View/download PDF
5. Duplex PCR for Detection of Aleutian Disease Virus from Biological and Environmental Samples
- Author
-
Kowalczyk, Marek, Jakubczak, Andrzej, and Gryzińska, Magdalena
- Abstract
Aleutian disease is one of the most serious disease entities affecting mink farms. The disease causes significant economic losses in mink breeding countries. The aim of the study was to optimize a diagnostic test based on duplex PCR to enable detection of Aleutian disease virus in biological and environmental samples.
- Published
- 2019
- Full Text
- View/download PDF
6. Diagnostics and genotyping of Canine parvovirus type 2 (CPV-2) from disease cases in south-eastern Poland
- Author
-
Kowalczyk, Marek, Majer-Dziedzic, Barbara, Kostro, Krzysztof, Szabelak, Aleksandra, Ziętek, Jerzy, Gryzinska, Magdalena, and Jakubczak, Andrzej
- Abstract
Canine parvovirus type 2 is one of the most common causes of death among puppies. Despite preventive vaccination, the disease continues to be diagnosed. The aim of the study was to provide a molecular characterization of CPV-2 isolates found in southeastern Poland. Genetic CPV-2 material was isolated from the blood (n=10) and feces (n=50) of infected dogs. The presence of CPV-2 was confirmed by amplification of sequences coding both VP1 and VP2 protein. The products of the PCR reaction with primers amplifying VP2 protein were sequenced and used for genotyping. Bioinformatics analysis of the sequenced PCR product was performed to determine the phylogenetic relationships with variants recorded in the public databases. Based on the analysis of polymorphism in the nucleotide sequence 7 nucleotide variants were detected and assigned into four amino acid groups. Representatives of three groups contained asparagine at amino acid position 426 of the VP2 protein, which is characteristic of CPV-2a. The variant from the fourth group belonged to type CPV-2b. CPV-2a is the dominant antigenic type of CPV-2 in Poland. The pathogen’s high degree of polymorphism is manifested not only by the presence of numerous variants within the type, but also by the presence of representatives of type CPV-2b. Further studies of the molecular epidemiology of CPV-2 are necessary to optimize the effectiveness of preventive measures.
- Published
- 2019
- Full Text
- View/download PDF
7. Geological and Geomorphologic Conditions and Traces of Prehistoric and Historic Human Settlements in the Vicinity of Ulów (Roztocze Region, Southeastern Poland)
- Author
-
Rodzik, Jan, Niezabitowska-Wiśniewska, Barbara, Nitychoruk, Jerzy, Budziszewski, Janusz, and Jakubczak, Michał
- Abstract
The paper presents determinants of location of the multicultural complex of archaeological sites in the vicinity of Ulów, in the Central Roztocze upland region in south-eastern Poland. Archaeological research revealed that in the area assumed to be devoid of settlements, the settlements of prehistoric and historical communities functioned from the Palaeolithic to modern times. The region was also subjected to environmental examination. Location of sites was analysed, taking into account a convenience of communication in a regional scale and local environmental conditions. Analysis of hydrogeological, geomorphological and soil conditions was carried out, taking into account water supply, communication and the farming development. In-depth analysis included micromorphological DTM (Digital Terrain Model) and geological and soil probing. The area was found to be located on the crossing of prehistoric communication routes the course of which depended on the variability of the physiographic parameters of regions. The functioning of new cultures in the same place resulted from specific local conditions such as: easily arable soils, favourable microclimate, and particularly access to water. The presence of a source of water in a plateau area is determined tectonically (strike-slip fault), lithologically (impermeable marl horizon), and geomorphologically (dissection of the aquifer by an erosion-denudation valley).
- Published
- 2017
- Full Text
- View/download PDF
8. Selected health behaviours of type 2 diabetes patients
- Author
-
Samolińska, Wioletta, Kiczorowska, Bożena, Kowalczuk-Vasilev, Edyta, Klebaniuk, Renata, and Jakubczak, Ewelina
- Abstract
Introduction.Type 2 diabetes is a chronic disease with an epidemic character. Its prevalence is associated with lifestyle, many environmental factors, and genetic determinants. Implementation of diet therapy is the basis for treatment of the disease.
- Published
- 2017
- Full Text
- View/download PDF
9. IGF1 Gene Polymorphism in Selected Species of the Canidae Family
- Author
-
Jakubczak, Andrzej, Gryzinska, Magdalena, Horecka, Beata, and Jezewska-Witkowska, Grazyna
- Abstract
The gene IGF1 has been shown to have a significant influence on the size of individuals, including animals of the Canidae family. In this study we determined SNP mutations of the IGF1 gene in dogs, raccoon dogs and farmed and free-living red foxes from Poland and Canada. No SNP mutations were noted in dogs or raccoon dogs, but a total of 14 single nucleotide polymorphisms were identified in foxes, including 12 substitutions, as well as one new mutation missense variant (exon 6) in wild Polish foxes and one synonymous mutation variant in wild foxes from Canada. We identified specific SNP profiles characteristic only for farmed foxes and only for wild foxes, as well as specific SNP profiles or wild foxes from North America (Canada) and from Europe (Poland).
- Published
- 2017
- Full Text
- View/download PDF
10. Effect of HMB and 2-Ox administered during pregnancy on bone properties in primiparous and multiparous minks (Neivison vison)
- Author
-
Tomaszewska, Ewa, Dobrowolski, Piotr, Kostro, Krzysztof, Jakubczak, Andrzej, Taszkun, Iwona, Jaworska-Adamu, Jadwiga, Żmuda, Andrzej, Rycerz, Karol, and Muszyński, Siemowit
- Abstract
The aim of the study was to determine the mechanical and geometric properties as well as bone tissue density of long bones in primiparous and multiparous dams of minks supplemented with β-hydroxy β-methylbutyrate (HMB) and/or 2-oxoketoglutarate (2-Ox) during gestation. Powdered 2-Ox was given at the daily dosage of 0.4 g/kg b.w. separately or simultaneously with HMB, which was administered at the daily dosage of 0.02 g/kg b.w. The study demonstrates for the first time that administration of 2-Ox and/or HMB to dams markedly influences bone tissue density and the mechanical and geometrical properties of mother`s bones in minks. Moreover, it was demonstrated that the supplementation was more effective in the thoracic limb, which was comprehensively used in contrast to the pelvic limb. The mechanical parameters and bone tissue density significantly increased in the humerus in multiparous minks. Only such diet may provide satisfactory production results in the animals. Nutritional deficiencies occurring during pregnancies may trigger body`s own reserves to cover the bone mass increase in developing foetuses and support milk production. This can prevent regeneration of dams’ organisms, which negatively affects their reproductive performance. 2-Ox or HMB may be regarded as a protective metabolite when administered orally to minks, counteracting the negative influences of pregnancy and lactation periods on bones condition. Both simultaneous treatment with 2-Ox and HMB and their separate administration were equally effective.
- Published
- 2015
- Full Text
- View/download PDF
11. Analysis of Genetic Variability in Farmed and Wild Populations of Raccoon Dog (Nyctereutes Procyonoides) Using Microsatellite Sequences
- Author
-
Kasperek, Kornel, Horecka, Beata, Jakubczak, Andrzej, Ślaska, Brygida, Gryzińska, Magdalena, Bugno-Poniewierska, Monika, Piórkowska, Małgorzata, and Jeżewska-Witkowska, Grażyna
- Abstract
The aim of this study was to detect possible differences between farmed and wild-living raccoon dogs. Analysis of polymorphism in 15 microsatellite sequences led to the conclusion that raccoon dogs raised on Polish farms and wild raccoon dogs living in Poland are two genetically distinct groups of animals. Wild Polish raccoon dogs are genetically more similar to the population of wild animals from the Kaliningrad Region than to farmed animals. The analysis of microsatellite loci showed clear genetic differences between farmed and wild-living populations of raccoon dog, despite only 50 years of isolation of the two groups of animals. The farmed population was characterized by higher genetic variation than the wild-living population. On the basis of the analyses three microsatellite loci (INU014, Ren13J22 and Ren41D20) were proposed for determination of the origin of animals that have escaped from farms.
- Published
- 2015
- Full Text
- View/download PDF
12. Low-energy impact behaviour and damage characterization of carbon fibre reinforced polymer and aluminium hybrid laminates
- Author
-
Bieniaś, J., Jakubczak, P., Surowska, B., and Dragan, K.
- Abstract
The purpose of this paper is to investigate the impact behaviour and damage characterization of carbon fibre reinforced aluminium hybrid laminates (Al/CFRP) in comparison to classic carbon fibre reinforced polymer (CFRP) at low-velocity and low-energy impact. Impact damage characteristic with damage initiation and progression, internal failure modes and understanding of the role of the metal layers in the impact behaviour under low-energy were examined and discussed. The damage mechanism of the tested laminates is very complex. There is an internal degradation of the material, with the plastic deformation in case of fibre metal laminates. Characteristic matrix cracks (bending and shearing cracks) running at the fibre–matrix interface in composite layers are the first damage mode. The critical damage mode is delaminations observed between composite layers with different orientation as well as delaminations at the metal–composite interface in fibre metal laminates. For the tested materials, particularly carbon fibre reinforced composites, the absorbed impact energy is mainly connected with elastic response and damage of the laminate. In case of fibre metal laminates the absorbed energy is also connected with plastic deformation of the laminate, occurring especially in the metal layers. High impact resistance of fibre metal laminates indicates that metal (aluminium) layers may prevent delamination propagation and impactor penetration.
- Published
- 2015
- Full Text
- View/download PDF
13. Effects of changes in intracellular iron pool on AlkB-dependent and AlkB-independent mechanisms protecting E.colicells against mutagenic action of alkylating agent
- Author
-
Sikora, Anna, Maciejewska, Agnieszka M., Poznański, Jarosław, Pilżys, Tomasz, Marcinkowski, Michał, Dylewska, Małgorzata, Piwowarski, Jan, Jakubczak, Wioletta, Pawlak, Katarzyna, and Grzesiuk, Elżbieta
- Abstract
•The intracellular free iron in E.coli hemHappear to be double that in wt strain.•Increased Fe(II) and AlkB concentrations result in decreased MMS-induced mutations.•Dealkylation of dNTPs takes place in the presence of Fe(II) and not requires AlkB.
- Published
- 2015
- Full Text
- View/download PDF
14. Cytogenetic Characterization of the Genome of Interspecies Hybrids (Alopex-Vulpes)
- Author
-
Bugno-Poniewierska, Monika, Pawlina, Klaudia, Orszulak-Wolny, Natalia, Woźniak, Bartosz, Wnuk, Maciej, Jakubczak, Andrzej, and Jeżewska-Witkowska, Grażyna
- Abstract
Creation of interspecific hybrids is widely common among plants and animals in order to improve economically important traits for humans. The studied material consisted of chromosomal preparations in the metaphase stage obtained from interspecies hybrids of arctic foxes (Alopex
- Published
- 2015
- Full Text
- View/download PDF
15. In silicoanalysis of methylation of the selected genes using computer programs based on various analytical techniques
- Author
-
Gryzińska, Magdalena, Jakubczak, Andrzej, Stryjecki, Robert, and Jeżewska-Witkowska, Grażyna
- Abstract
Selected genes were analyzed in silicoin three species: red fox (Vulpes vulpes), raccoon dog (Nyctereutes procyonoides), and dog (Canis lupus familiaris). This type of analysis exemplifies current and potential research on gene expression. Four nucleotide sequences, of the genes IGF1, MYO15A, PAX3and MC1R, were obtained from the NCBI online database. The analyses focused on the presence of CpG islands and two analytical techniques, BSP and MSP. The results from three computer programs, CpG Island Searcher®, BiSearch®and MethPrimer®, were discussed in detail. The applications were compared in terms of their functionality and usefulness.
- Published
- 2015
- Full Text
- View/download PDF
16. Non-toxic 2D Ti3C2MXene surface-modified with Al, Ga, In alkoxides by chemical reactions with metal trialkyls
- Author
-
Wojciechowski, Tomasz, Jastrzębska, Agnieszka Maria, Vasilchenko, Alexey S., Jakubczak, Michał, Wolska-Pietkiewicz, Małgorzata, Rozmysłowska-Wojciechowska, Anita, Moszczyńska, Dorota, Olszyna, Andrzej, and Ziemkowska, Wanda
- Abstract
Understanding the surface chemistry and reactivity of 2D MXenes is of fundamental importance in developing more advanced functional materials. In this work, we describe multilayered Ti3C2MXene-based materials such as Ti3C2/Al3+, Ti3C2/In3+and Ti3C2/Ga3+, obtained by modifying the MXene surface with aluminum-, indium- and gallium alkoxides. In the synthesis of these materials, organometallic compounds of group 13 metals (Et3Al, Me3In, and Et3Ga) were chosen as precursors for the alkoxides to modify the surface. To attach organometallic compounds to the MXene surface, their high reactivity towards the terminal OH, = O and F groups present on the MXene surface was used. In the next step, exposure of the surface-attached aluminum-, indium and gallium alkyls to air allowed their transformation into metal alkoxides due to the high reactivity of the metal-carbon bonds to oxygen and water. In our method of MXene modification, the alkoxide precursors can be extended to other organometallic compounds, such as groups 1, 2 and 12 alkyls. Microbiological studies of the developed 2D Ti3C2/Al3+, Ti3C2/In3+and Ti3C2/Ga3+alkoxides showed no acute ecotoxicity to the tested microorganisms. The obtained materials did not influence bioluminescent/biosensor-type microorganisms nor reduce the viability of other types of microorganisms, such as Staphylococcus aureus, Escherichia colior Candida albicans.The obtained results clearly indicate that the surface modification of 2D Ti3C2MXene with group 13 metal compounds is highly prospective toward the development of various types of materials that do not show any adverse effects to living organisms.
- Published
- 2022
- Full Text
- View/download PDF
17. Genetic variability of farmed and free-living populations of red foxes (Vulpes vulpes)
- Author
-
Jeżewska-Witkowska, Grażyna, Horecka, Beata, Jakubczak, Andrzej, Kasperek, Kornel, Ślaska, Brygida, Bugno-Poniewierska, Monika, and Piórkowska, Małgorzata
- Abstract
This study was designed to determine the degree of genetic distinctiveness between farmed and wild foxes (Vulpes vulpes). Analysis of polymorphism in 16 microsatellite sequences led to the conclusion that red foxes raised on Polish farms and wild foxes living in Poland are two groups of genetically distinct animals. Farmed Polish foxes are genetically more similar to the population of wild animals from North America than they are to the free-living population in Poland, as confirmed by the fact that the farmed animals are descended from animals raised in Canada.
- Published
- 2012
- Full Text
- View/download PDF
18. Efficient surface processing by ultrafast XUV/NIR dual action
- Author
-
Mocek, T., Jakubczak, K., Chalupsky, J., Park, S. B., Lee, G. H., Kim, T. K., Nam, C. H., Hajkova, V., Toufarova, M., Gemini, L., Margarone, D., Juha, L., and Rus, B.
- Abstract
We have developed a novel method for efficient structuring of the surface of materials by applying femtosecond near infrared laser pulses simultaneously with a weak extreme ultraviolet beam, which leads to a very strong radiation-matter interaction and brings a dramatic increase of the surface processing speed. We present our recent experimental results on surface nanostructuring of thin films of amorphous carbon and polymethyl methacrylate deposited on bulk substrates and discuss the underlying physical mechanisms. In the case of amorphous carbon, large areas of laser-induced periodic surface structures with a spatial period of 550 nm were created, having their origin in laser-induced convective currents. Our method provides a powerful tool for fast modification of tribological properties of the irradiated sample.
- Published
- 2011
- Full Text
- View/download PDF
19. Assessment of Selenium Concentration in Selected Organs of Farmed Raccoon Dogs (Nyctereutes Procyonoides)
- Author
-
Seremak, Beata, Pilarczyk, Bogumiła, Tomza-Marciniak, Agnieszka, Pilarczyk, Renata, Jakubczak, Andrzej, Dziadosz, Małgorzata, Pławski, Kamil, and Hendzel, Diana
- Abstract
Assessment of Selenium Concentration in Selected Organs of Farmed Raccoon Dogs (Nyctereutes Procyonoides)The aim of the study was to determine selenium concentrations in the liver, kidneys, lungs, heart and muscles of farmed raccoon dogs (Nyctereutes procyonoides) and to evaluate their impact on hair coat quality. Selenium concentration was determined using the modified Watkinson's spectrofluorometric method. Subjects were 20 farmed raccoon dogs (Nyctereutes procyonoides) at the age of 8-9 months, which were kept on a farm in south-eastern Poland. The results show that liver selenium content averaged 0.23±0.10 μg/g w.w. (wet weight). The concentrations ranged from 0.04 to 0.49 μg/g w.w. Kidney selenium concentration (0.49±0.17 μg/g w.w. on average) was over twice that of liver concentration. Animals with higher scores for hair coat quality had lower selenium concentrations in the kidneys and liver, and higher selenium concentrations in muscles, but the differences were not significant. When relating Se concentrations determined in the liver of raccoon dogs to the biochemical criteria, it is concluded that 80% of the analysed raccoon dogs were deficient in this element and 20% had marginal levels. The results obtained in our study suggest that the food used on the farm did not fully meet the Se requirement of the raccoon dogs.
- Published
- 2011
- Full Text
- View/download PDF
20. Beam properties of fully optimized, table-top, coherent source at 30 nm
- Author
-
Jakubczak, K., Mocek, T., Rus, B., Polan, J., Hrebicek, J., Sawicka, M., Sikocinski, P., Sobota, J., Fort, T., and Pina, L.
- Abstract
We present results on development and experimental implementation of a 1-kHz, coherent extreme ultraviolet (XUV) radia- tion source based on high-order harmonic generation of the femtosecond, near-infrared laser pulses produced by the titanium-doped sapphire laser system (35 fs, 1.2 mJ, 810 nm) at the Institute of Physics AS CR / PALS Centre. The source comprises a low-density static gas cell filled with a conversion medium, typically argon. The comprehensive optimization of the XUV harmonic source has been performed with respect to major parameters such as gas pressure in the cell, cell length, position of the focus of the driving laser field with respect to the gas cell position, size of the driving near-infrared laser beam, chirp of the femtosecond pulse, and the focal length of the lens deployed in the experimental setup. Harmonic spectra were recorded using an XUV transmission grating spectrometer developed specifically for this purpose. Detailed characterization of the XUV source has been performed including measurement of the XUV beam profile, M2 parameter of the beam, absolute energy, and spatial coherence.
- Published
- 2011
- Full Text
- View/download PDF
21. Link-alike
- Author
-
Jakubczak, Szymon, Andersen, David, Kaminsky, Michael, Papagiannaki, Konstantina, and Seshan, Srinivasan
- Abstract
Asymmetric broadband connections in the home provide a limited upstream pipe to the Internet. This limitation makes various applications, such as remote backup and sharing high definition video, impractical. However, homes in a neighborhood often have high bandwidth wireless networks, whose bandwidth exceeds that of a single wired uplink. Moreover, most (wired and wireless) connections are idle most of the time. In this paper, we examine the fundamental requirements of a system that aggregates upstream broadband connections in a neighborhood using wireless communication between homes. A scheme addressing this problem must operate efficiently in an environment that is: i) highly lossy; ii) broadcast in nature; and iii) half-duplex. We propose a novel scheme, Link-alike, that addresses those three challenges using opportunistic wireless reception, a novel wireless broadcast rate control scheme, and preferential use of the wired downlink. Through analytical and experimental evaluation, we demonstrate that our approach provides significantly better throughput than previous solutions based on TCP or UDP unicast.
- Published
- 2009
- Full Text
- View/download PDF
22. Application of Multiplex PCR for Monitoring Colonization of Pig Tonsils by Yersinia enterocolitica, Including Biotype 1A, and Yersinia pseudotuberculosis
- Author
-
Kot, Barbara, Trafny, Elżbieta A., and Jakubczak, Antoni
- Abstract
A multiplex PCR assay was developed for the detection and differentiation of the Yersinia enterocoliticaand Yersinia pseudotuberculosisisolates in both pure bacterial cultures and pig tonsils. The assay was based on the amplification of the ail, inv, yadA, and ystBgenes. The PCR products, corresponding to the ailgene and the plasmid-borne yadAgene or only one product corresponding to the ailgene, were detected in Y. enterocolitica4 biotype isolates. All of the Y. pseudotuberculosisisolates (n= 6) tested gave a positive PCR reaction for the invgene. For all tested Y. enterocolitica1A biotype isolates (n= 31), one product corresponding to the ystBgene was observed. The multiplex PCR assay was used to detect Y. enterocoliticaand Y. pseudotuberculosisstrains in pig tonsil samples obtained from 80 slaughtered pigs from three different herds. The presence of at least one of the specific PCR amplification products of ail-, ystB-, yadA-, and inv-specific sequences was observed in 11 samples (13.75%). These results of the multiplex PCR assay were compared with the results of conventional, microbiological testing. Y. enterocoliticaisolates were cultured from only 3 (3.75%) of the 80 pig tonsils examined. The multiplex PCR assay was shown to be an efficient tool for differentiation between the pYV plasmid–bearing Y. enterocoliticaisolates, the plasmidless Y. enterocoliticaisolates, the Y. enterocoliticabiotype 1A isolates, and the Y. pseudotuberculosisisolates with and without the pYV plasmid in naturally contaminated pig tonsils. This indicates that this assay is useful to control food processing and track the source of contamination.
- Published
- 2007
- Full Text
- View/download PDF
23. Clonal Structure of Enterococcus faecalisIsolated from Polish Hospitals: Characterization of Epidemic Clones
- Author
-
Kawalec, Magdalena, Pietras, Zbigniew, Danilowicz, Emilia, Jakubczak, Aleksandra, Gniadkowski, Marek, Hryniewicz, Waleria, and Willems, Rob J. L.
- Abstract
ABSTRACTTo study the population structure of Enterococcus faecalisfrom Polish hospitals, 291 isolates were typed by pulsed-field gel electrophoresis and a novel multilocus sequence typing scheme (P. Ruiz-Garbajosa et al., J. Clin. Microbiol. 44:2220-2228, 2006). The isolates originated from geographically widespread medical institutions and were recovered during a 10-year period (1996 to 2005) from different clinical sources. The analysis grouped the isolates into five epidemic and 71 sporadic clones. The importance of the previously identified global clonal complexes CC2 and CC9 was corroborated by our findings that two of the Polish epidemic clones, A and J, were classified into these clonal complexes (CCs). However, the two most predominant clones, C (ST40) and F (CC87), did not cluster in the aforementioned CCs and may represent novel epidemic CCs. These clones may have emerged in Central Europe. Clone F, carrying glycopeptide resistance determinants of VanA or VanB phenotypes, caused several outbreaks in hematology units and appeared to be the most prevalent clone in recent years in Poland. Antimicrobial susceptibility testing and additional tests for pathogenicity-related phenotypes (hemolysin and gelatinase production) and genes (asa1and esp) were performed to further characterize these epidemic clones. Multidrug resistance, glycopeptide resistance, presence of asa1, and production of hemolysin appeared to be statistically significant features related to epidemicity. Production of gelatinase was significant for two of the epidemic clones, whereas presence of the espgene was not specific for the epidemic clones.
- Published
- 2007
- Full Text
- View/download PDF
24. Adenovirus Type 5 Viral Particles Pseudotyped with Mutagenized Fiber Proteins Show Diminished Infectivity of Coxsackie B-Adenovirus Receptor-Bearing Cells
- Author
-
Jakubczak, John L., Rollence, Michele L., Stewart, David A., Jafari, Jonathon D., Von Seggern, Dan J., Nemerow, Glen R., Stevenson, Susan C., and Hallenbeck, Paul L.
- Abstract
ABSTRACTA major limitation of adenovirus type 5 (Ad5)-based gene therapy, the inability to target therapeutic genes to selected cell types, is attributable to the natural tropism of the virus for the widely expressed coxsackievirus-adenovirus receptor (CAR) protein. Modifications of the Ad5 fiber knob domain have been shown to alter the tropism of the virus. We have developed a novel system to rapidly evaluate the function of modified fiber proteins in their most relevant context, the adenoviral capsid. This transient transfection/infection system combines transfection of cells with plasmids that express high levels of the modified fiber protein and infection with Ad5.ßgal.?F, an E1-, E3-, and fiber-deleted adenoviral vector encoding ß-galactosidase. We have used this system to test the adenoviral transduction efficiency mediated by a panel of fiber protein mutants that were proposed to influence CAR interaction. A series of amino acid modifications were incorporated via mutagenesis into the fiber expression plasmid, and the resulting fiber proteins were subsequently incorporated onto adenoviral particles. Mutations located in the fiber knob AB and CD loops demonstrated the greatest reduction in fiber-mediated gene transfer in HeLa cells. We also observed effects on transduction efficiency with mutations in the FG loop, indicating that the binding site may extend to the adjacent monomer in the fiber trimer and in the HI loop. These studies support the concept that modification of the fiber knob domain to diminish or ablate CAR interaction should result in a detargeted adenoviral vector that can be combined simultaneously with novel ligands for the development of a systemically administered, targeted adenoviral vector.
- Published
- 2001
- Full Text
- View/download PDF
25. Antiangiogenic Gene Therapy for Cancer via Systemic Administration of Adenoviral Vectors Expressing Secretable Endostatin
- Author
-
Chen, Cheauyun T., Lin, Jane, Li, Qin, Phipps, Sandrina S., Jakubczak, John L., Stewart, David A., Skripchenko, Yelena, Forry-Schaudies, Suzanne, Wood, Jeanette, Schnell, Christian, and Hallenbeck, Paul L.
- Abstract
A growing number of antiangiogenesis strategies have been investigated for the treatment of cancer and other angiogenesis-dependent diseases. One of the most promising strategies is to systemically administer one or more antiangiogenic proteins frequently enough to achieve a sufficient long-term steady state level of the protein(s) to achieve the maximum beneficial effect. However, the utility of this strategy is limited because of many technical difficulties, including obtaining both the quantity and quality of the protein(s) necessary for optimal therapeutic benefit. To overcome these difficulties, we hypothesized that a single administration of a replication-defective adenoviral vector expressing a secretable antiangiogenic protein could achieve an optimal long-term systemic concentration. We constructed a recombinant adenoviral vector, Av3mEndo, which encodes a secretable form of murine endostatin. We demonstrated secretion of endostatin from several cell lines transduced with Av3mEndo. Partially purified endostatin secreted from Av3mEndo-transduced mammalian cells was shown to potently inhibit endothelial cell migration in vitro. A single intravenous administration of Av3mEndo in mice was shown to result in (1) prolonged and elevated levels of circulating endostatin, (2) partial inhibition of VEGF-induced angiogenesis in a VEGF implant angiogenesis model, and (3) prolonged survival and in 25% of mice the complete prevention of tumor growth in a prophylactic human colon/liver metastasis xenograft murine model. These results support our contention that adenoviral vectormediated expression of an antiangiogenic protein(s) represents an attractive therapeutic approach to cancer and other angiogenesis-dependent diseases.
- Published
- 2000
- Full Text
- View/download PDF
26. Disassociation of Met-Mediated Biological Responses In Vivo: the Natural Hepatocyte Growth Factor/Scatter Factor Splice Variant NK2 Antagonizes Growth but Facilitates Metastasis
- Author
-
Otsuka, Toshiyuki, Jakubczak, John, Vieira, Wilfred, Bottaro, Donald P., Breckenridge, Diane, Larochelle, William J., and Merlino, Glenn
- Abstract
ABSTRACTHepatocyte growth factor/scatter factor (HGF/SF) stimulates numerous cellular activities capable of contributing to the metastatic phenotype, including growth, motility, invasiveness, and morphogenetic transformation. When inappropriately expressed in vivo, an HGF/SF transgene induces numerous hyperplastic and neoplastic lesions. NK1 and NK2 are natural splice variants of HGF/SF; all interact with a common receptor, Met. Although both agonistic and antagonistic properties have been ascribed to each isoform in vitro, NK1 retains the full spectrum of HGF/SF-like activities when expressed as a transgene in vivo. Here we report that transgenic mice broadly expressing NK2 exhibit none of the phenotypes characteristic of HGF/SF or NK1 transgenic mice. Instead, when coexpressed in NK2-HGF/SF bitransgenic mice, NK2 antagonizes the pathological consequences of HGF/SF and discourages the subcutaneous growth of transplanted Met-containing melanoma cells. Remarkably, the metastatic efficiency of these same melanoma cells is dramatically enhanced in NK2 transgenic host mice relative to wild-type recipients, rivaling levels achieved in HGF/SF and NK1 transgenic hosts. Considered in conjunction with reports that in vitro NK2 induces scatter, but not other activities, these data strongly suggest that cellular motility is a critical determinant of metastasis. Moreover, our results demonstrate how alternatively structured ligands can be exploited in vivo to functionally dissociate Met-mediated activities and their downstream pathways.
- Published
- 2000
- Full Text
- View/download PDF
27. Disassociation of Met-Mediated Biological Responses In Vivo: the Natural Hepatocyte Growth Factor/Scatter Factor Splice Variant NK2 Antagonizes Growth but Facilitates Metastasis
- Author
-
Otsuka, Toshiyuki, Jakubczak, John, Vieira, Wilfred, Bottaro, Donald P., Breckenridge, Diane, Larochelle, William J., and Merlino, Glenn
- Abstract
Hepatocyte growth factor/scatter factor (HGF/SF) stimulates numerous cellular activities capable of contributing to the metastatic phenotype, including growth, motility, invasiveness, and morphogenetic transformation. When inappropriately expressed in vivo, an HGF/SF transgene induces numerous hyperplastic and neoplastic lesions. NK1 and NK2 are natural splice variants of HGF/SF; all interact with a common receptor, Met. Although both agonistic and antagonistic properties have been ascribed to each isoform in vitro, NK1 retains the full spectrum of HGF/SF-like activities when expressed as a transgene in vivo. Here we report that transgenic mice broadly expressing NK2 exhibit none of the phenotypes characteristic of HGF/SF or NK1 transgenic mice. Instead, when coexpressed in NK2-HGF/SF bitransgenic mice, NK2 antagonizes the pathological consequences of HGF/SF and discourages the subcutaneous growth of transplanted Met-containing melanoma cells. Remarkably, the metastatic efficiency of these same melanoma cells is dramatically enhanced in NK2 transgenic host mice relative to wild-type recipients, rivaling levels achieved in HGF/SF and NK1 transgenic hosts. Considered in conjunction with reports that in vitro NK2 induces scatter, but not other activities, these data strongly suggest that cellular motility is a critical determinant of metastasis. Moreover, our results demonstrate how alternatively structured ligands can be exploited in vivo to functionally dissociate Met-mediated activities and their downstream pathways.
- Published
- 2000
- Full Text
- View/download PDF
28. Short-beam shear fatigue life assessment of thermally cycled carbon–aluminium laminates with protective glass interlayers
- Author
-
Surowska, Barbara, Dadej, Konrad, Jakubczak, Patryk, and Bieniaś, Jarosław
- Abstract
Fibre metal laminates (FMLs) are attractive construction materials, especially for use in aerospace and transport facilities. Throughout their service life, thin-walled structures made of FMLs are exposed to static and dynamic loads, as well as corrosion and the unfavourable influence of environmental conditions. The paper presents an experimental analysis of the combined mechanical and environmental long-term behaviour of carbon-based fibre metal laminates and their variants with protective glass layers. The Al alloy/CFRP and Al alloy/GFRP/CFRP laminates in a 3/2 configuration were used. The tested laminates were subjected to 1500 thermal cycles with a temperature range of 130 °C. The static and fatigue interlaminar shear strengths were tested before and after thermal conditioning. It was shown that the stable stiffness reduction in the tested laminates was observed with increasing fatigue cycles, due to the progressive fatigue damage accumulation. The thermally cycled laminates feature slightly smoother stiffness loss, while a more rapid decrease was observed in thermally untreated laminates. Moreover, the fatigue life of the tested laminates subjected to thermal cycling revealed nine times fewer fatigue cycles of laminates with glass protectors after thermal cycles in comparison to the laminates not subjected to thermal cycling.
- Published
- 2021
- Full Text
- View/download PDF
29. Oxygen availability for bacterial growth with a flow microcalorimeter
- Author
-
Herman, J. P., Jakubczak, E., Belaich, J. P., and Leclerc, H.
- Abstract
The enthalpy change associated with aerobic growth of E. coli K
12 on minimal media with succinic acid as sole carbon and energy source, determined by flow microcalorimetry (with aerobic mixing cell) was 733.01±15.32 kJ·mol-1 . Molar growth yield was 39.6±1.2 g·mol-1 . When the microcalorimetric growth was limited by oxygen supply, the power-time curve was altered and the total heat evolved was less than the enthalpy change. The maximum thermal output corresponding to a fully aerobic growth in the calorimetric cell was 1.89×10-3 W·ml-1 . Thus, the oxygen uptake rate was about 0.39 ml O2 ·h-1 ·ml-1 .- Published
- 1982
- Full Text
- View/download PDF
30. Perinatal Methylmercury Poisoning in Iraq
- Author
-
Amin-Zaki, Laman, Elhassani, Sami, Majeed, Mohammed A., Clarkson, Thomas W., Doherty, Richard A., Greenwood, Michael R., and Giovanoli-Jakubczak, Teresa
- Abstract
• The signs and symptoms of methylmercury poisoning and the concentrations of mercury in samples of blood, hair, and milk are reported and compared in two infant-mother pairs exposed in the recent Iraq outbreak.1 In one pair, the infant was born prior to the exposure of the mother, and was exposed only from ingestion of methylmercury in mother's milk. In the other pair, the mother was exposed during pregnancy and did not breast feed the infant, who died 30 days after birth. Both mothers had some signs and symptoms of poisoning, but the infants did not. The infants had maximum estimated blood mercury levels between
- Published
- 1976
- Full Text
- View/download PDF
31. Sequence relationship of retrotransposable elements R1 and R2 within and between divergent insect species.
- Author
-
Burke, W D, Eickbush, D G, Xiong, Y, Jakubczak, J, and Eickbush, T H
- Abstract
R1 and R2 are retrotransposable elements that integrate at specific sites in the 28S ribosomal RNA (rRNA) genes of Bombyx mori and Drosophila melanogaster. We have previously shown that most insect species contain insertions in their 28S genes at the R1 and/or R2 site. We have sequenced the 3' half of R1 and R2 elements from three additional insect species: the fungus gnat, Sciara coprophila (Diptera); the Japanese beetle, Popillia japonica (Colleoptera); and the parasitic wasp, Nasonia vitripennis (Hymenoptera). The elements were obtained by screening lambda phage genomic clones containing rDNA units and by a polymerase chain reaction approach using degenerate primers to conserved sequences in the reverse-transcriptase domain, in combination with a second primer to the 28S gene 3' of the insertion site. Comparisons of the sequences of R1 and R2 from four insect orders suggest that the organization of their open-reading frames has been conserved and is therefore likely to be similar throughout insects. This sequence analysis also indicates that, except for 5' truncations generated during the retrotransposition process itself, most elements have not accumulated mutations that would make them inactive. Popillia japonica and N. vitripennis differed from previously described species, in that (a) P. japonica contained multiple families of R2 and (b) N. vitripennis contained multiple families of R1. Nucleotide sequence identity between these different families is low. Amino acid sequence identity of their open-reading frames averaged only 41% for the R2 families of P. japonica and 35% for the R1 families of N. vitripennis. The presence of multiple highly divergent families of elements within a species suggests either that each insertion family is able to maintain its copy number without eliminating the other families in its competition for a limited number of 28S genes or that there has been extensive horizontal transfer of R1 and R2 elements between insect species.
- Published
- 1993
- Full Text
- View/download PDF
32. Retrotransposable elements R1 and R2 interrupt the rRNA genes of most insects.
- Author
-
Jakubczak, J L, Burke, W D, and Eickbush, T H
- Abstract
A large number of insect species have been screened for the presence of the retrotransposable elements R1 and R2. These elements integrate independently at specific sites in the 28S rRNA genes. Genomic blots indicated that 43 of 47 insect species from nine orders contained insertions, ranging in frequency from a few percent to greater than 50% of the 28S genes. Sequence analysis of these insertions from 8 species revealed 22 elements, 21 of which corresponded to R1 or R2 elements. Surprisingly, many species appeared to contain highly divergent copies of R1 and R2 elements. For example, a parasitic wasp contained at least four families of R1 elements; the Japanese beetle contained at least five families of R2 elements. The presence of these retrotransposable elements throughout Insecta and the observation that single species can harbor divergent families within its rRNA-encoding DNA loci present interesting questions concerning the age of these elements and the possibility of cross-species transfer.
- Published
- 1991
- Full Text
- View/download PDF
33. ON THE CAUSES OF MONOPHAGY IN DROSOPHILA QUINARIA
- Author
-
James, Avis C., Jakubczak, John, Riley, Michael P., and Jaenike, John
- Published
- 1988
- Full Text
- View/download PDF
34. NK1, a Natural Splice Variant of Hepatocyte Growth Factor/Scatter Factor, Is a Partial Agonist In Vivo
- Author
-
Jakubczak, John L., Larochelle, William J., and Merlino, Glenn
- Abstract
ABSTRACTHepatocyte growth factor/scatter factor (HGF/SF) is a potent mitogen, motogen, and morphogen for epithelial cells expressing its tyrosine kinase receptor, the c-metproto-oncogene product, and is required for normal development in the mouse. Inappropriate stimulation of Met signal transduction induces aberrant morphogenesis and oncogenesis in mice and has been implicated in human cancer. NK1 is a naturally occurring HGF/SF splice variant composed of only the amino terminus and first kringle domain. While the biological activities of NK1 have been controversial, in vitro data suggest that it may have therapeutic value as an HGF/SF antagonist. Here, we directly test this hypothesis in vivo by expressing mouse NK1 in transgenic mice and comparing the consequent effects with those observed for mice carrying an HGF/SF transgene. Despite robust expression, NK1 did not behave as an HGF/SF antagonist in vivo. Instead, NK1-transgenic mice displayed most of the phenotypic characteristics associated with HGF/SF-transgenic mice, including enlarged livers, ectopic skeletal-muscle formation, progressive renal disease, aberrant pigment cell localization, precocious mammary lobuloalveolar development, and the appearance of mammary, hepatocellular, and melanocytic tumors. And like HGF/SF-transgenic livers, NK1 livers had higher levels of tyrosine-phosphorylated complexes associated with Met, suggesting that the mechanistic basis for the effects of NK1 overexpression in vivo was autocrine activation of Met. We conclude that NK1 acts in vivo as a partial agonist. As such, the efficacy of NK1 as a therapeutic HGF/SF antagonist must be seriously questioned.
- Published
- 1998
- Full Text
- View/download PDF
35. NK1, a Natural Splice Variant of Hepatocyte Growth Factor/Scatter Factor, Is a Partial Agonist In Vivo
- Author
-
Jakubczak, John L., Larochelle, William J., and Merlino, Glenn
- Abstract
ABSTRACTHepatocyte growth factor/scatter factor (HGF/SF) is a potent mitogen, motogen, and morphogen for epithelial cells expressing its tyrosine kinase receptor, the c-metproto-oncogene product, and is required for normal development in the mouse. Inappropriate stimulation of Met signal transduction induces aberrant morphogenesis and oncogenesis in mice and has been implicated in human cancer. NK1 is a naturally occurring HGF/SF splice variant composed of only the amino terminus and first kringle domain. While the biological activities of NK1 have been controversial, in vitro data suggest that it may have therapeutic value as an HGF/SF antagonist. Here, we directly test this hypothesis in vivo by expressing mouse NK1 in transgenic mice and comparing the consequent effects with those observed for mice carrying an HGF/SF transgene. Despite robust expression, NK1 did not behave as an HGF/SF antagonist in vivo. Instead, NK1-transgenic mice displayed most of the phenotypic characteristics associated with HGF/SF-transgenic mice, including enlarged livers, ectopic skeletal-muscle formation, progressive renal disease, aberrant pigment cell localization, precocious mammary lobuloalveolar development, and the appearance of mammary, hepatocellular, and melanocytic tumors. And like HGF/SF-transgenic livers, NK1 livers had higher levels of tyrosine-phosphorylated complexes associated with Met, suggesting that the mechanistic basis for the effects of NK1 overexpression in vivo was autocrine activation of Met. We conclude that NK1 acts in vivo as a partial agonist. As such, the efficacy of NK1 as a therapeutic HGF/SF antagonist must be seriously questioned.
- Published
- 1998
- Full Text
- View/download PDF
36. Dose-dependent selective facilitation of response-contingent light-onset behavior by d-amphetamine
- Author
-
Gomer, Frank E. and Jakubczak, Leonard F.
- Abstract
The influence of d-amphetamine on the acquisition of light-contingent bar-pressing was assessed in rats in a two-lever operant task as a function of dose and incentive value of the sensory reinforcer. Relative to saline-injected controls, amphetamine increased the probability of discriminated responding on the active reward-bar at the 0.75 but not at the 2.50 mg/kg dosage level. Further, only at the lower dose was the effect of incentive condition significant, with animals receiving variant light-onset emitting a greater percentage of presses on the active bar than animals receiving invariant light-onset. It was concluded that low doses of amphetamine do not enhance all categories of behavior in the rat in a learning situation, but selectively facilitate only those responses directed by the reinforcement contingencies. In addition, the poor performance observed for animals injected with the higher dosage in the present experiment may have been due to the stimulated perseveration of stereotypic behavior patterns which were incompatible with the task requirements.
- Published
- 1974
- Full Text
- View/download PDF
37. Frequency, duration, and speed of wheel running of rats as a function of age and starvation
- Author
-
Jakubczak, Leonard
- Abstract
The purpose of this experiment was to determine whether age differences in amounts of wheel running of starved rats were due to the frequency of bursts of running, to the average duration of bursts, to speed, or to any combination of these parameters. The experiment was carried out according to a 3 by 2 by 2 mixed model design. The independent variables were age (67, 293, and 746 days old at the start of starvation), food deprivation (total starvation vs ad lib), and occasion of measurement (initial vs maximum activity). The dependent variables were number of wheel revolutions, number of bursts of activity, number of seconds of running per burst, and revolutions per second. The results indicated that acutely starved rats run more often, for longer periods, and at higher speeds than do sated rats, and that with increased age rats run less often, for a shorter time, and at slower speeds.
- Published
- 1973
- Full Text
- View/download PDF
38. Aberration-free laser beam in the soft x-ray range
- Author
-
Goddet, J. Ph., Sebban, S., Gautier, J., Zeitoun, Ph., Valentin, C., Tissandier, F., Marchenko, T., Lambert, G., Ribières, M., Douillet, D., Lefrou, T., Iaquaniello, G., Burgy, F., Maynard, G., Cros, B., Robillard, B., Mocek, T., Nejdl, J., Kozlova, M., and Jakubczak, K.
- Abstract
By seeding an optical-field-ionized population-inverted plasma amplifier with the 25th harmonic of an IR laser, we have achieved what we believe to be the first aberration-free laser beam in the soft x-ray spectral range. This laser emits within a cone of 1.34 mrad(1/e^2) at a repetition rate of 10 Hz at a central wavelength of 32.8 nm. The beam exhibits a circular profile and wavefront distortions as low as λ/17. A theoretical analysis of these results shows that this high beam quality is due to spatial filtering of the seed beam by the plasma amplifier aperture.
- Published
- 2009
39. PROGRESS THROUGH COLLABORATION: A CASE STUDY EXAMINING EFFECTS OF INDUSTRIAL SOUNDS ON BOWHEAD WHALES
- Author
-
STREEVER, B., ANGLISS, R.P., SUYDAM, R., AHMAOGAK, M., BAILEY, C., BLACKWELL, S.B., GEORGE, J.C., GREENE, C.R., JAKUBCZAK, R.S., LEFEVRE, J., McDONALD, T.L., NAPAGEAK, T., and RICHARDSON, W.J.
- Published
- 2008
- Full Text
- View/download PDF
40. Demonstration of a spatial filtering amplifier for high-order harmonics
- Author
-
Goddet, J. Ph., Sebban, S., Morlens, A. S., Gautier, J., Rousseau, J. Ph., Burgy, F., Zeitoun, Ph., Valentin, C., Hauri, C., Maynard, G., Boudaa, A., Caumes, J. P., Merdji, H., Mocek, T., Kozlova, M., and Jakubczak, K.
- Abstract
We report what is to our knowledge the first demonstration of spatial filtering of a high-order harmonic beam into a soft-x-ray laser plasma amplifier at 32.8 nm. After amplification the seed energy is enhanced by a factor of 50, and the beam profile of the amplified beam exhibits an Airy-like shape due to the spatial filtering by the optical field ionized plasma. Moreover, the transverse coherence of the spatially filtered amplified beam is strongly enhanced, resulting in the generation of a peak coherent power of 0.9×10^5 to 1.8×10^5 W.
- Published
- 2007
41. Food intake as a function of age and food deprivation
- Author
-
Jakubczak, Leonard
- Abstract
The purpose of this experiment was to determine whether or not there were age differences in the effects of increasing durations of food deprivation on food intake in rats. The experiment was carried out according to a 3 by 3 by 3 by 7 mixed design consisting of three age groups of 12 female Sprague-Dawley rats each (4, 11, and 24 months), subdivided into three sequence-effects control groups (ABC, BCA, CAB), with each rat exposed to each food-deprivation duration (24, 48, and 96 h), and refeeding measured for 7 days. The dependent variables were: latency to eat, amount of food per day consumed during refeeding, and body weight. Prior to food deprivation , the 4-month-old rats ate less than the 11-month-old rats or the 24-month-old rats , but these differences were proportional to age differences in body weight. The effects of duration of deprivation, order, and days of refeeding were proportional across age, suggesting equal responsivity to the effects of these factors on food intake across a large segment of the life span of the female rat.
- Published
- 1973
- Full Text
- View/download PDF
42. Artificial larynx prosthesis: Comparative clinical evaluation
- Author
-
Henley‐Cohn, Julian L., Hausfeld, Jeffrey N., and Jakubczak, Gene
- Abstract
The work pioneered by Drs. Singer and Blom established the clinical feasibility of controlled tracheoesophageal fistula for generation of fluent esophageal speech. There have been numerous practical difficulties that have been encountered with the use of voice prosthesis. Problems encountered are: extrusion, speech initiation delay, leakage around the prosthesis, stoma obstruction, and low volume output.
- Published
- 1984
- Full Text
- View/download PDF
43. Re-entrainment of food intake of mature and old rats to the light-dark cycle
- Author
-
Jakubczak, L.
- Abstract
Are there age-related decrements in the re-entrainment of food intake of rats following an inversion of the light-dark cycle? An experiment using 17 male rats was carried out according to a 2 by 2 by 7 design, with repeated measures on the last two factors, representing age of rat (220 and 785 days), time of day (0600-1800 h vs. 1800-0600 h), and daysets (0-6). The primary dependent variable was grams of food eaten during each 12-h period. The results indicate that prior to the light reversal the older rats ate more during the light phase of the light-dark cycle than the younger rats, but did not differ from them during the dark phase; and that the older rats entrained their food intake at a slower absolute rate than the younger rats, but at an equal relative rate. These results suggest that senescent rats are as adaptable to changes in their environment as mature rats.
- Published
- 1975
- Full Text
- View/download PDF
44. Effects of food deprivation and initial levels on a wheel-running response to methamphetamine
- Author
-
Jakubczak, Leonard and Gomer, Frank
- Abstract
The purpose of this experiment was to determine the time course and peak effects of methamphetamine on wheel-running activity of food-deprived rats and to determine whether degree of food deprivation and/or predeprivation levels interactwith dosage to influence running activity. The experiment was carried out according to a 4 by 3 by 2 by 5 design, representing four dosage levels of methamphetamine HC1 (0.00, 0.75, 1.50, and 3.00 m g/kg), three food-deprivation conditions (90%, 80%, and 70% of ad lib body weight), two blocks of rats formed on the basis of predeprivation levels of running, and five hourly samples of running activity. The results indicated that the peak effects of methamphetamine on running activity occur with a dose of 1.50 mg/kg, during the first hour after injection, and are additiveto the effects of food deprivation and predeprivation running levels.
- Published
- 1973
- Full Text
- View/download PDF
45. SoftCast
- Author
-
Jakubczak, Szymon and Katabi, Dina
- Abstract
The focus of this demonstration is the performance of streaming video over the mobile wireless channel. We compare two schemes: the standard approach to video which transmits H.264/AVC-encoded stream over 802.11-like PHY, and SoftCast -- a clean-slate design for wireless video where the source transmits one video stream that each receiver decodes to a video quality commensurate with its specific instantaneous channel quality.
- Published
- 2011
- Full Text
- View/download PDF
46. N019 A phased heart failure pathway: Improving patient outcomes
- Author
-
Jakubczak, M. and Lewis, K.
- Published
- 2011
- Full Text
- View/download PDF
47. SoftCast
- Author
-
Jakubczak, Szymon and Katabi, Dina
- Abstract
The focus of this demonstration is the performance of streaming video over the mobile wireless channel. We compare two schemes: the standard approach to video which transmits H.264/AVC-encoded stream over 802.11-like PHY, and SoftCast -- a clean-slate design for wireless video where the source transmits one video stream that each receiver decodes to a video quality commensurate with its specific instantaneous channel quality.
- Published
- 2010
- Full Text
- View/download PDF
48. Age differences in caloric-density preference as a function of strain of rats
- Author
-
Jakubczak, Leonard
- Abstract
When young rats, as well as humans, are presented with diets that differ in caloric density (kilocalories/gram), they prefer the calorically dense diet. How these preferences change with age is not known. A 2 by 2 by 3 by 7 experiment, representing strain, age, caloric-density difference, and day sets, was carried out in order to determine the influence of these factors on preference for calorically dense diets. The results indicated that, depending on the strain, old rats prefer calorically dense diets either to an equal degree or to a lesser degree than do young rats.
- Published
- 1973
- Full Text
- View/download PDF
49. Preliminary Results of a Phase 2 Study of PD 0332991 in Combination with Bortezomib and Dexamethasone in Patients with Relapsed and Refractory Multiple Myeloma
- Author
-
Niesvizky, Ruben, Costa, Luciano J, Haideri, Nisreen A., Hess, Georg, Singhal, Seema, Spicka, Ivan, Stadtmauer, Edward A., Badros, Ashraf Z., Raab, Marc S, Jakubczak, John L, Kim, Sindy T., Randolph, Sophia, Ely, Scott A, and Chen-Kiang, Selina
- Abstract
PD 0332991 is an orally bioavailable selective inhibitor of cyclin-dependent kinase (CDK) 4/6. Inhibition of CDK4/6 phosphorylation of retinoblastoma (Rb) induces prolonged early G1 cell cycle arrest (pG1) and synchronous progression to S phase (pG1-S) upon withdrawal, which sensitizes human multiple myeloma (MM) cells to killing by bortezomib (B) or dexamethasone (D) in vitro and in animal models. Based on these observations, a phase 1/2 study in combination with B plus D in patients (pts) with relapsed and/or refractory MM was initiated. The phase 1 part of the study (completed) determined the recommended phase 2 dose and schedule to be PD 0332991 100 mg QD 12 days on followed by 9 days off treatment in a 21-day cycle with intravenous B 1.0 mg/m2 plus oral D 20 mg administered on Days 8 and 11 in pG1 and 15 and 18 in pG1-S (Niesvizky et al. ASH 2010). We present preliminary data from the phase 2 part of the study.Pts with Rb protein-positive, measurable (as defined by International Myeloma Working Group [IMWG]) progressive, relapsed or refractory MM after ≥1 prior treatment were eligible. Prior B was allowed only if there was a response and disease progression occurred off therapy. Pts received oral PD 0332991 once daily on Days 1–12 in a 21-day cycle in combination with intravenous B 1.0 mg/m2 plus oral D 20 mg administered on Days 8, 11, 15, and 18. The primary endpoint is overall response rate (ORR); secondary endpoints include time to progression (TTP), progression-free survival (PFS), overall survival, duration of response, and safety. PD 0332991-mediated inhibition of CDK4/6-specific phosphorylation of Rb (pSRb) and Ki67 in bone marrow MM cells were also assessed. The phase 2 part of the study is a Simon Two-Stage Minimax design; 25 response evaluable patients were to be enrolled into the first stage.39 pts have been tested for Rb and 36 pts (92%) were positive. Of the 36 pts, 30 pts have been enrolled to date including 2 pts who did not receive the study treatment, and 23 pts are considered response evaluable as of the data cut-off. 56% of pts had an Eastern Cooperative Oncology Group performance status (ECOG PS) of 1 and 8% had ECOG PS of 2. At baseline, median β2 microglobulin was 3.1 (range 1.6–26.2), median hemoglobin was 11.2 (7.2–13.6), median calcium was 9.4 (8.7–11.9). The median number of prior therapies was 2 (range 1–8); 55% had received prior B. Sixteen pts have discontinued (9 due to progressive disease, 3 due to AE, 2 consent withdrawal, and 2 not treated). The most common treatment-related AEs were thrombocytopenia (44%), nausea (20%), anemia, constipation, fatigue, and neutropenia (all 16%); 32% of pts reported grade ≥3 thrombocytopenia. IHC data showed on-treatment reduction in pSRb and Ki67 in MM cells from bone marrow of 3/3 patients with available samples. To date, 1 pt achieved a complete response (CR), 1 achieved a very good partial response (VGPR), 1 partial response (PR), 1 minor response (MR), and 5 stable disease (SD); 6 pts are too early for assessment.To date, the combination of PD 0332991 and B plus D has shown response in 4 pts with relapsed/refractory MM. The most commonly reported AEs were cytopenias, consistent with the known safety profiles of PD 0332991 and B. PD 0332991 inhibited phosphorylation of Rb and cell cycle progression in MM cells. The accrual to stage 1 is ongoing. Updated efficacy and safety data will be presented.Niesvizky: Millennium Pharmaceuticals: Consultancy; Millennium Pharmaceuticals: Research Funding; Millennium Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees. Hess:Pfizer Oncology: Consultancy; Pfizer Oncology: Research Funding; Pfizer Oncology: Membership on an entity's Board of Directors or advisory committees. Spicka:Janssen-Cilag: Consultancy; Celgene: Consultancy; Celgene: Research Funding; Janssen-Cilag: Honoraria; Celgene: Honoraria; Janssen-Cilag: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees. Jakubczak:Pfizer Oncology: Employment; Pfizer Oncology: Equity Ownership. Kim:Pfizer Oncology: Equity Ownership; Pfizer Oncology: Employment. Randolph:Pfizer Oncology: Employment; Pfizer Oncology: Equity Ownership. Chen-Kiang:Pfizer Oncology: Research Funding.
- Published
- 2011
- Full Text
- View/download PDF
50. Preliminary Results of a Phase 2 Study of PD 0332991 in Combination with Bortezomib and Dexamethasone in Patients with Relapsed and Refractory Multiple Myeloma
- Author
-
Niesvizky, Ruben, Costa, Luciano J, Haideri, Nisreen A., Hess, Georg, Singhal, Seema, Spicka, Ivan, Stadtmauer, Edward A., Badros, Ashraf Z., Raab, Marc S, Jakubczak, John L, Kim, Sindy T., Randolph, Sophia, Ely, Scott A, and Chen-Kiang, Selina
- Abstract
Abstract 2940
- Published
- 2011
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.