NF-κB-associated mechanisms underlying the response of embryonic cells to Doxorubicin.

The involvement of NF-κB in the regulation of teratogen-induced apoptosis has not been established yet. Therefore, we tried to assess the involvement of the p65 subunit of NF-κB in the embryonic response to the anti-cancer drug Doxorubicin (DOX). Thus, exposure of p65 knockout (p65(-/-)) or wild type (WT) mouse embryonic fibroblasts (MEFs) to DOX resulted in a decrease in cell survival, culture density and cell proliferation, which was found to be more prominent in p65(-/-) MEFs.

Effect of maternal immunopotentiation on apoptosis-associated molecules expression in teratogen-treated embryos.

Problem: Potentiation of the maternal immune system was shown by us to affect the embryonic response to teratogenic insults. In order to understand better the mechanisms underlying that phenomenon, we explored the effect of maternal immunopotentiation by rat splenocytes on the early stages of the embryonic response to cyclophosphamide (CP).

Method Of Study: Immunopotentiated CP-treated embryos were analysed for cell cycle changes by flow cytometry, while cell proliferation and apoptosis were assessed by 5'-bromo-2'-deoxyuridine (BrdU) incorporation and terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick-end labeling (TUNEL) respectively.

Tumor necrosis factor-alpha-associated mechanisms affecting the embryonic response to cyclophosphamide.

Problem: We have previously shown that TNF-alpha(-/-) embryos are more sensitive to the exposure to cyclophosphamide (CP) compared with TNF-alpha(+/+) embryos; however, the underlying mechanisms are not fully understood. Thus, in our present study, we tried to identify those molecules that might be responsible for the protective effect of the cytokine.

Method Of Study: CP-treated TNF-alpha(-/-) and TNF-alpha(+/+) embryos were analyzed for changes in apoptosis by TUNEL and flow cytometry, while cell proliferation was analyzed by BrdU incorporation.

Biomechanical comparison of lasso, Pulvertaft weave, and side-by-side tendon repairs.

Background: The authors' group has developed and used a lasso repair as a substitute to the Pulvertaft weave when joining two tendons for tendon grafts and transfers. This study compared the maximum load, weave time, tendon length required, and bulkiness of the lasso, Pulvertaft weave, and side-by-side repairs.

Methods: Sixty porcine trotter flexor tendons were used to perform 30 repairs--10 lasso, 10 Pulvertaft weave, and 10 side-by-side.

Bax-associated mechanisms underlying the response of embryonic cells to methotrexate.

Bax was shown previously to regulate apoptotic cell death in various experimental systems, however, its involvement in teratogen-induced apoptosis is not clear yet. Therefore, we explored the involvement of Bax in the response of mouse embryonic fibroblasts (MEFs) to the anti cancer drug methotrexate (MTX), using Bax wild type (WT) and knockout (Bax(-/-)) MEFs. Our results demonstrated a significant teratogen-induced dose- and time-dependant decrease in the survival and culture density of both cell lines, which were found to be somewhat more prominent in WT cells.

Renal apoptosis following carbon dioxide pneumoperitoneum in a rat model.

Purpose: Laparoscopically recruited kidneys regain normal function more slowly than laparotomy harvested organs for several possible reasons. We investigated the effects of CO(2) induced pneumoperitoneum on kidney function, as reflected by blood and urine creatinine levels, and its relation with renal cell apoptosis.

Materials And Methods: CO(2) pneumoperitoneum was established in anesthetized Wistar male rats that were randomly allocated at 6 per group into 1 of 6 groups with an intraperitoneal pressure of 0 (control), 5, 8, 12, 15 or 18 mm Hg.

Expression of apoptosis-associated molecules in the fetoplacental unit of cyclophosphamide-treated mice.

The mechanisms underlying the teratogen-induced apoptotic process leading to anomaly formation are not as yet understood. Therefore, we tried to evaluate possible changes in the expression of molecules regulating the apoptotic process induced in the embryo and placenta by exposure to cyclophosphamide (CP). Exposure to CP resulted in clear growth retardation that was accompanied by a time-dependent increase in cellular damage and an appearance of apoptotic cells in the embryonic brain and limbs as well as a decrease in cell proliferation.

TNF-alpha acts to prevent occurrence of malformed fetuses in diabetic mice.

Aims/hypothesis: Activation of apoptosis in embryos is thought to be a key event in the pathogenesis of diabetes-induced embryopathies such as early embryonic death and inborn structural anomalies. TNF-alpha can activate apoptotic and anti-apoptotic signalling cascades, indicating its ability to contribute to and counteract diabetes-induced maldevelopment. To investigate how TNF-alpha regulates the response of embryos to diabetes-induced embryopathic stress, we used streptozotocin-induced diabetic TNF-alpha knockout mice.

Safety and efficacy in an accredited outpatient plastic surgery facility: a review of 5316 consecutive cases.

Advances in medicine have improved the delivery of health care, making it more technologically superior than ever and, at the same time, more complex. Nowhere is this more evident than in the surgical arena. Plastic surgeons are able to perform procedures safely in office-based facilities that were once reserved only for hospital operating rooms or ambulatory surgery centers.

TNF-alpha protects embryos exposed to developmental toxicants.

Background: Tumor necrosis factor alpha (TNF-alpha) has been implicated in mediating post-implantation embryo loss or the embryonic maldevelopment induced by development toxicants or maternal metabolic imbalances. In order to clarify the role of TNF-alpha further, a comparative study was performed in TNF-alpha, knockout and TNF-alpha, positive mice, exposed to a reference teratogen, cyclophosphamide (CP).

Methods: Cyclophosphamide was injected on day 12 of pregnancy and 18-day fetuses were examined for external structural anomalies.

Potentiation of the maternal immune system may modify the apoptotic process in embryos exposed to developmental toxicants.

Problem: We have previously shown that teratogen-induced embryonic maldevelopment may result from excessive apoptosis in affected organs, but the mechanisms underlying this process are not well understood. Here we investigate the ability of maternal immunopotentiation to affect the apoptotic process and its regulatory genes p53 and bcl-2 in embryos exposed to a teratogenic insult.

Method Of Study: Potentiation of the immune system in pregnant females was performed with xenogeneic rat splenocytes or with granulocyte macrophage-colony stimulating factor (GM-CSF).

Increased TNF-alpha expression in cultured mouse embryos exposed to teratogenic concentrations of glucose.

Diabetes-induced early embryonic death is accompanied by an increased expression of tumour necrosis factor alpha (TNF-alpha) in the embryonic microenvironment. The aim of the present study was to evaluate whether diabetes-induced embryopathic stress may also alter the expression of TNF-alpha produced by the embryo itself. As a model, whole postimplantation embryos were cultured for 24 h in a medium with high concentrations of glucose, one of the main diabetes-associated teratogenic metabolites.

Apoptosis in the uterus of mice with pregnancy loss.

Problem: The mechanisms mediating pregnancy loss induced by various agents are far from being understood. Thus, we investigated the possible involvement of one such mechanism, the apoptotic process, in pregnancy loss induced by lipopolysaccharide (LPS) or cyclophosphamide (CP) as well as the associated changes in the apoptosis-regulating gene products p53 and bcl-2.

Method Of Study: Pregnancy loss was induced by LPS or CP on days 9 or 12 of pregnancy, respectively.

NF-kappa B DNA-binding activity in embryos responding to a teratogen, cyclophosphamide.

Background: The Rel/NF-kappaB transcription factors have been shown to regulate apoptosis in different cell types, acting as inducers or blockers in a stimuli- and cell type-dependent fashion. One of the Rel/NF-kappaB subunits, RelA, has been shown to be crucial for normal embryonic development, in which it functions in the embryonic liver as a protector against TNFalpha-induced physiological apoptosis. This study assesses whether NF-kappaB may be involved in the embryo's response to teratogens.

Cytokine expression in the uterus of mice with pregnancy loss: effect of maternal immunopotentiation with GM-CSF.

It is believed that failure of the maternal immune system to actively support embryonic development, through production of the appropriate cytokine network, might be responsible for embryonic death. Thus, the aim of this study was to evaluate the possible involvement of cytokines such as tumour necrosis factor alpha (TNF-alpha) and transforming growth factor beta2 (TGF-beta2), which are crucial for normal embryonic development, in the early stages of mechanisms that mediate induced pregnancy loss. The early stages of the resorption process induced by lipopolysaccharide (LPS) were characterized by blood accumulation in the vicinity of the embryo, preceding any visible embryonic damage.

Diabetes teratogenicity in mice is accompanied with distorted expression of TGF-beta2 in the uterus.

Early embryonic deaths as well as malformed newborns are among complications of the diabetic pregnancy. Cytokines and growth factors operating in the embryonic vicinity are found to be among factors that determine the sensitivity of embryos to external and internal detrimental stimuli, including diabetes. Transforming Growth Factor-beta2 (TGF-beta2) has been shown to be essential for embryonic development and survival.

Expression of tumor necrosis factor-alpha in the pregnant uterus of diabetic mice: effect of maternal immunopotentiation.

Problem: Tumor necrosis factor (TNF)-alpha mRNA and protein are expressed in the pregnant uterus of streptozotocin-induced diabetic mice at various stages of pregnancy. We intend to characterize their pattern and to evaluate whether the potentiation of the maternal immune system alters the pattern of the expression of the cytokine.

Method Of Study: Diabetes was induced in ICR mice by streptozotocin injection.

TGFbeta2 in embryos with inborn anomalies: effect of maternal immunopotentiation.

Problem: TGFbetas are among the main immunoregulatory molecules contributing to successful embryonic development. Besides, our and other studies revealed that maternal immunopotentiation has a potential to increase the resistance of the embryo to the teratogenic insult. This work was designed to evaluate: (1) whether the formation of teratogen-induced anomalies is accompanied by an altered pattern of TGFbeta2 expression in embryonic cells and (2) whether maternal immunopotentiation modifies the pattern of TGFbeta2 expression in embryos responding to the teratogenic insult.

Restoration of elbow flexion after brachial plexus injury: the role of nerve and muscle transfers.

Brachial plexus trauma results in a variable loss of upper extremity function. The restoration of this function requires elbow flexion of adequate strength and range of motion. A proper evaluation of brachial plexus lesions is a prerequisite to any reconstructive procedure, and appropriate guidelines are presented.

Mersilene suture as a vehicle for delivery of growth factors in tendon repair.

Extensive clinical and laboratory studies have demonstrated that growth factors accelerate and modulate the wound-healing process. The purpose of this experiment was to apply the principles of growth factor-enhanced wound healing to an in vitro rat tendon model. A method was developed for covalently binding a biologically active peptide to nonabsorbable braided polyester suture (Mersilene).

TNF-alpha expression in embryos exposed to a teratogen.

Problem: The role of tumor necrosis factor (TNF)-alpha produced by embryonic cells in normal and abnormal development is poorly understood. To assess to what extent TNF-alpha may be involved in the process of induced dysmorphogenesis, the expression of TNF-alpha and TNF-alpha receptor (TNFRI) mRNA as well as TNF-alpha protein was evaluated in embryos responding to a cyclophosphamide (CP)-induced teratogenic insult. The effect of maternal immunostimulation increasing the embryo's tolerance to CP on TNF-alpha expression was also investigated.

TNF-alpha messenger RNA and protein expression in the uteroplacental unit of mice with pregnancy loss.

An elevated expression of TNF-alpha in embryonic microenvironment was found to be associated with postimplantation loss. In this work, we examined the pattern of TNF-alpha expression at both the mRNA and the protein level as well as the distribution of TNF-alpha receptor mRNA in the uteroplacental unit of mice with induced (cyclophosphamide-treated) or spontaneous (CBA/J x DBA/2J mouse combination) pregnancy loss. RNase protection analysis demonstrated an increase in TNF-alpha mRNA expression in the placentae of mice with pregnancy loss compared with that in control mice.