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Here, we report the development of an integrated laser Doppler blood flow micrometer for chickens. This sensor weighs only 18 g and is one of the smallest-sized blood flow meters, with no wired line, these are features necessary for attaching the sensor to the chicken. The structure of the sensor chip consists of two silicon cavities with a photo diode and a laser diode, which was achieved using the microelectromechanical systems technique, resulting in its small size and significantly low power consumption. In addition, we introduced an intermittent measuring arrangement in the measuring system to reduce power consumption and to enable the sensor to work longer. We were successfully able to measure chicken blood flow for five consecutive days, and discovered that chicken blood flow shows daily fluctuations. [ABSTRACT FROM PUBLISHER]

Tumor necrosis factor-alpha (TNF-alpha) is known as a pluripotent cell mediator, and it is implicated in the control of uterine cell growth, differentiation and function during estrous cycle and pregnancy. In this study, we investigated the effect of TNF-alpha on endometrial stromal cells derived from rat uterus (rat endometrial stromal cells, RES). RES were isolated from rat endometrium at day 5 of pregnancy. Proliferation activities of RES were measured by using bromodeoxyuridine (BrdU) labeling kit, the productions of prostaglandin E2 (PGE2) and prostaglandin F2alpha (PGF2alpha) were measured by enzyme immunoassay kits and the production of matrix metalloproteinases (MMPs) was analyzed by gelatin-zymography. TNF-alpha, as well as epidermal growth factor and fibroblast growth factor-2, significantly increased the proliferation activity of RES (P<0.05). TNF-alpha selectively stimulated the production of PGE2 in RES (P<0.05), but not the production of PGF2alpha. Additionally, TNF-alpha did not stimulate the production of MMPs in RES at the concentration of 5 ng/mL, compared with the control groups (P>0.05). In conclusion, this study demonstrates several regulational functions of TNF-alpha on RES using in vitro culture system. The effects of TNF-alpha on proliferation and MMP production of RES have been shown for the first time. We believe that these results demonstrate part of the functions of TNF-alpha in endometrium and contribute to the better understanding of endometrial functions.

A multifunctional growth and differentiation factor TGF-beta is expressed at various developmental stages, and its principle role may be involvement in organogenesis. The present study was performed to evaluate the temporal and spatial expression of TGF-beta2 mRNA in developing somites of chicken embryos during their early developmental periods. TGF-betas were expressed in various tissues of the whole embryo obtained at stage 26 (5 days of incubation) as revealed by whole-mount in situ hybridization. TGF-beta2 mRNA was predominantly expressed in somites as well as the head, branchial arch, wing buds, and leg buds. TGF-beta2 mRNA first appeared in the rostral somites on E4, and its expression sites expanded to the middle range of somites at stage 26. At stages 29-31 (6-7 days), expression in the rostral somites disappeared, and it appeared in the caudal somites. TGF-beta2 expression was also analyzed in sections of the embryo by in situ hybridization. The expression sites of TGF-beta2 were clearly observed in the myotomal somite tips as well as the neural tube. RT-PCR analysis showed that TGF-beta2 expression was very low in the blastocyte stage embryo and thereafter increased linearly in the whole trunk until stage 26. These data indicate that TGF-beta2 may be a regulatory factor participating in the somitogenesis of chicken embryos., (Copyright 2005 Wiley-Liss, Inc.)

The development of chicken embryonic gonads is locally regulated by the systematic action of growth factors. Recently, we used suppressive subtraction cloning to identify transforming growth factor beta2 (TGF-beta2) as a growth factor gene preferentially expressed in chicken embryonic ovaries and testes during the early periods of development (Hattori et al. 2002a. Prominent expression of transforming growth factor beta2 gene in the chicken embryonic gonad as revealed by suppressive subtraction cloning. Gen Comp Endocrinol 125:311-316). In the present study, the function of TGF-beta2 in chicken embryonic gonads was investigated using a serum-free culture system in the presence of several growth factors, which may behave as mitogenic or survival factors of primordial germ cells (PGCs). Chicken germinal ridges containing PGCs and germinal ridge stroma cells (GRSCs) were collected from six-day embryos. Addition of TGF-beta2 caused a dose-dependent inhibition of the number of co-cultured PGCs and GRSCs in the presence of these growth factors. However, there was no obvious difference between embryonic ovaries and testes in the effects of TGF-beta2. Immunocytochemical analysis using anti-SSEA-1 antibody revealed that TGF-beta2 induced fragmentation of PGCs. Expression of the TGF-beta2 gene was estimated in the co-cultured PGCs and GRSCs by semi-quantitative RT-PCR. The mRNA level of TGF-beta2 was significantly suppressed in the presence of the growth factors. These results suggest that TGF-beta2 is a gonadal regulator preferentially expressed at the early stages of chicken embryonic development and reduces the growth of PGCs and GRSCs by suppressing proliferation. However, expression of TGF-beta2 may be controlled by mitogenic or survival factors of PGCs., (Copyright 2004 Wiley-Liss, Inc.)

Aim: To confirm the stability of exogenous genes in the generation of transgenic chickens using ejaculated chicken sperm, the deoxyribonuclease (DNase) activity was evaluated in the seminal plasma of ejaculated semen and the stability of DNA was examined by adding lipofection reagents., Methods: A PCR fragment (249 bp) of pEGFPN-1 vector was used as the DNA substrate and was incubated with the seminal plasma at 40 degree C for 30 min. Then, the whole reaction solution was subjected to agarose gel electrophoresis and the DNA size was evaluated under UV light., Results: The DNA substrate was completely diminished after incubation with seminal plasma. However, the substrate was intact after incubation with heat-treated seminal plasma or incubation with seminal plasma in the presence of 0.5 mmol/L approximately 5 mmol/L EDTA. The substrate was stabilized in the seminal plasma by the addition of commercially available lipofection reagents., Conclusion: The DNase activity is present in the seminal plasma of ejaculated chicken semen. However, DNA is stable in the liposomal-DNA complex.

Aim: The production of interspecific germline chimeras between chicken and quail were attempted employing the dissociated cells derived from the blastodermal central disk (stage X) and the germinal crescent region of embryo (stage 7-8)., Methods: The central disk (CD) of the area pellucida in chicken blastoderm (stage X) and the germinal crescent region (GCR) of embryo (stage 7-8) were dispersed and injected into the subgerminal cavity of quail blastoderm (stage X). Injected eggs were incubated for 7 days or to hatching. The donor chicken DNA was detected by the polymerase chain reaction., Results: In day-7 embryos, chicken DNA was detected in 5 gonads and 9 brains from 53 survived embryos received chicken CD cells, and 1 gonads and 6 brains from 27 survived embryos received chicken GCR. Chicken DNA was also detected from the semen of one adult male hatched from eggs received chicken GCR cells., Conclusion: CD and GCR cells as the donors showed the possibility to produce the interspecific germline chimera, but further studies are needed to make necessary improvement.