Background: This study was conducted to evaluate effects of intraperitoneal administration of Giberellic Acid (GBA), a hormone of plants, on testicular tissue of adult rats. Materials and Methods: Thirty six adult male Wistar rats were divided into four groups (n=9). Control group was untreated, control-sham group injected 0.5cc 1% methanol, low dose of GBA group was administered 2 mg/kg and hi...

References .......................................................................... 59 Abstract In recent years, increasing number of cancer patients are treated with stereotactic radiosurgery (SRS) or stereotactic body radiation therapy (SBRT), which deliver hypofractionated irradiation with high-dose per fraction . It is highly likely that the radiobiological principles such as 4 Rs (Reoxyg...

Current approaches to tissue regeneration are limited by the death of most transplanted cells and/or resultant poor integration of transplanted cells with host tissue. We hypothesized that transplanting progenitor cells within synthetic microenvironments that maintain viability, prevent terminal differentiation, and promote outward migration would significantly enhance their repopulation and re...

The hematopoietic stem and progenitor cell (HSPC) compartment is subject to extensive quantitative genetic variation. We have previously shown that TGF-beta2 at low concentrations enhances flt3 ligand-induced growth of HSPCs, while it is potently antiproliferative at higher concentrations. This in vitro enhancing effect was subject to quantitative genetic variation, for which a quantitative tra...

To examine the process of liver repopulation by transplanted hepatocytes, we developed transgenic mice carrying a mouse major urinary protein-urokinase-type plasminogen activator fusion transgene. Expression of this transgene induced diffuse hepatocellular damage beginning at 3 weeks of age, and homozygous mice supported up to 97% parenchymal repopulation by healthy donor hepatocytes transplant...

Although embryonic stem (ES) cell-derived hepatocytes have the capacity for liver engraftment and repopulation, their in vivo hepatic function has not been analyzed yet. We aimed to determine the metabolic function and therapeutic action of ES cell-derived hepatocytes after serial liver repopulations in fumaryl acetoacetate hydrolase knockout (Fah(-/-)) mice. Albumin expressing (Alb(+)) cells w...

Many features of T-cell homeostasis in primates are still unclear, thus limiting our understanding of AIDS pathogenesis, in which T-cell homeostasis is lost. Here, we performed experiments of in vivo CD4(+) or CD8(+) lymphocyte depletion in 2 nonhuman primate species, rhesus macaques (RMs) and sooty mangabeys (SMs). Whereas RMs develop AIDS after infection with simian immunodeficiency virus (SI...

Pulmonary infections are important causes of morbidity and mortality in immunosuppressed patients after transplantation. After experimental irradiation and syngeneic bone marrow transplantation in mice, macrophages show reduced repopulation in the lung compared with that in other tissues. Macrophages are major microbicidal immune effector cells in host pulmonary defense. Therefore, we examined ...

The microenvironment within solid tumors is slightly acidic, and manipulation of this extracellular acidity to cause intracellular acidification might be used to increase selective antitumor effects of some anticancer drugs. Potential mechanisms include inhibition of repair of DNA damage and inhibition of repopulation of tumor cells between successive courses of chemotherapy. Here, we evaluate ...

Intraoperative radiotherapy differs from conventional, fractionated radiotherapy in several aspects that may influence its biological effect. The radiation quality influences the relative biologic effectiveness (RBE), and the role of the five R's of radiotherapy (reassortment, repair, reoxygenation, repopulation, radiosensitivity) is different. Furthermore, putative special biological effects a...