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Here we report urine-derived cell (UDC) culture and subsequent use for cloning which resulted in the successful development of cloned canine pups, which have remained healthy into adulthood. Bovine UDCs were used in vitro to establish comparative differences between cell sources. UDCs were chosen as a readily available and noninvasive source for obtaining cells. We analyzed the viability of cells stored in urine over time and could consistently culture cells which had remained in urine for 48hrs. Cells were shown to be viable and capable of being transfected with plasmids. Although primarily of epithelial origin, cells were found from multiple lineages, indicating that they enter the urine from more than one source. Held in urine, at 4°C, the majority of cells maintained their membrane integrity for several days. When compared to in vitro fertilization (IVF) derived embryos or those from traditional SCNT, UDC derived embryos did not differ in total cell number or in the number of DNA breaks, measured by TUNEL stain. These results indicate that viable cells can be obtained from multiple species' urine, capable of being used to produce live offspring at a comparable rate to other cell sources, evidenced by a 25% pregnancy rate and 2 live births with no losses in the canine UDC cloning trial. This represents a noninvasive means to recover the breeding capacity of genetically important or infertile animals. Obtaining cells in this way may provide source material for human and animal studies where cells are utilized. [ABSTRACT FROM AUTHOR]

Canine cloning is occasionally accompanied by abnormal sexual development. Some male donor cells produce cloned pups with female external genitalia and complete male gonadal dysgenesis, which is classified as an XY disorder of sex development (XY DSD). In this study, we examine the potential of 5-aza-2'-deoxycytidine (5-aza-dC), a DNA methyltransferase inhibitor, to reduce the phenotypic abnormality XY DSD in somatic cell nuclear transfer (SCNT)- derived pups. We used a 9-year-old normal male German Shepherd dog as a cell donor. Donor cells were treated with 10 nM 5-aza-dC for 4 days before being used for SCNT. At the same stage of cell development, significantly lower levels of DNA methylation of the sex-determining region Y (SRY) promoter was observed in the treated donor cells compared to that in the untreated cells (95.2% versus 53.3% on day 4 for the control and treated groups, respectively). No significant differences were observed in the control or treatment groups concerning fusion rate, pregnancy rate (30 days or entire period), the number of pups, or the incidence of XY DSD. However, more XY DSD dogs were observed in the control group (31.25%) than in the treatment group (14.29%). Hypermethylation of the SRY promoter was observed in the XY DSD cloned pups in both the treatment (84.8%) and control groups (91.1 ± 1.4%) compared to the methylation level in the phenotypically normal male pups of the treatment (23.2 ± 20.9%) and control groups (39.1 ± 20.1%). These results suggest that 5-aza-dC treatment of donor cells can reduce the methylation level of the SRY promoter in donor cells, and thus, 5-aza-dC is advantageous for reducing the incidence of XY DSD in canine cloning. [ABSTRACT FROM AUTHOR]

We report on the fabrication and characterization of synthesized multiwall MoS2 nanotube (NT) and nanoribbon (NR) field-effect transistors (FETs). The MoS2 NTs and NRs were grown by chemical transport, using iodine as a transport agent. Raman spectroscopy confirms the material as unambiguously MoS2 in NT, NR, and flake forms. Transmission electron microscopy was used to observe cross sections of the devices after electrical measurements and these were used in the interpretation of the electrical measurements, allowing the estimation of the current density. The NT and NR FETs demonstrate n-type behavior, with ON/OFF current ratios exceeding 10³, and with current densities of 1.02 μA/μm and 0.79 μA/μm at VDS = 0.3 V and VBG = 1V, respectively. Photocurrent measurements conducted on a MoS2 NT FET revealed short-circuit photocurrent of tens of nanoamps under an excitation optical power of 78 μW and 488 nm wavelength, which corresponds to a responsivity of 460 μA/W. A long channel transistor model was used to model the common-source characteristics of MoS2 NT and NR FETs and was shown to be consistent with the measured data. [ABSTRACT FROM AUTHOR]

Reduviidae (assassin bugs) is the second largest family of the hemipteran suborder Heteroptera (true bugs). The family contains 25 subfamilies, the largest number amongst true bugs, and 28 tribes. Most previously published keys do not include all recognized subfamilies and even complete keys lead to incorrect identifi cation of certain taxa. We here present a comprehensive and well-illustrated identifi cation key to subfamilies and tribes (except Emesinae) of Reduviidae. The key is complemented by taxon treatments that provide, for each subfamily, diagnostic features, notes on taxonomy and distribution, a comment on taxa occurring in Canada, natural history notes, and a short bibliography. [ABSTRACT FROM AUTHOR]