Clinicopathological significance of the expression of estrogen receptor-beta and vascular endothelial growth factor-A in colorectal cancer.

Estrogen-receptor-beta (ERβ), progesterone receptor (PR) and vascular endothelial growth factor (VEGF-A) have been implicated in colorectal cancer. However, the clinicopathological significance of any expression of these markers remains unclear. Immunohistochemical assays of ERα, ERβ, PR, and VEGF-A were performed on 72 colorectal cancer cases.

Protective effect of methylprednisolone on warm ischemia-reperfusion injury in a cholestatic rat liver.

Background: Cholestasis has been identified as a risk factor for oxidative stress, and it potentially enhances after ischemic-reperfusion injury. The aim of this study was to evaluate the role of methylprednisolone on warm ischemia-reperfusion injury in the presence of cholestasis.

Methods: A reversible cholestatic rat model was created.

Comparison of osteogenic potential of calvarial bone dust, bone fragments, and periosteum.

Introduction: Bone dust is often used as a control when testing the potential of a new reconstructive graft material. Under microscopic examination, it would be expected to see the fully differentiated cellular components of bone, but instead only fusiform shapes characteristic of fibroblasts are mainly seen. This study aimed to compare the osteogenic potential of cells obtained from calvarial bone dust, bone fragments, and periosteum using 3 assays: collagen, calcium, and alkaline phosphatase.

A specific vascular endothelial growth factor receptor tyrosine kinase inhibitor enhances the antiproliferative effect of trastuzumab in human epidermal growth factor receptor 2 overexpressing breast cancer cell lines.

Background: Trastuzumab has been found to have potent antiproliferative effects in human epidermal growth factor receptor 2 (HER-2)-overexpressing human breast tumors. Inhibition of vascular endothelial growth factor receptor (VEGFR), a protein often overexpressed in breast carcinoma, has been shown to induce apoptosis.

Methods: Breast carcinoma cell lines were cultured with increasing doses of trastuzumab and/or a VEGFR tyrosine kinase inhibitor (TKI).

Actions and comparative efficacy of phosphatidylcholine formulation and isolated sodium deoxycholate for different cell types.

Background: Phosphatidylcholine formulation has been used to dissolve local fat deposits. This study aimed to evaluate and compare the effects of phosphatidylcholine formulation and its vehicle sodium deoxycholate alone on different cell lines to understand better its mechanism of action.

Methods: Cells and media including 3T3-L1 preadipocytes, normal foreskin fibroblasts, neonatal human dermal microvascular endothelial cells (CADMEC), and fetal human skeletal muscle cells (HSkMC) were used.

Repairing critical-sized rat calvarial defects with a periosteal cell-seeded small intestinal submucosal layer.

Background: Small intestinal submucosa was evaluated as a bioscaffold candidate for periosteum-derived osteoblasts, and its suitability as a bone replacement material for cranial defects was investigated.

Methods: In the in vitro phase, osteoblasts were expanded in osteogenic medium and were then seeded onto small intestinal submucosa. To confirm osteoblast phenotype, they were tested for alkaline phosphatase, collagen type 1, and calcium expression.

An alternative method for harvest and processing fat grafts: an in vitro study of cell viability and survival.

Background: Adipocyte viability has been emphasized as essential for fat graft survival. There is no universal agreement on the methodology for handling fat grafts.

Objective: Two different methods of fat harvesting and techniques of tissue processing were compared by assessing cell viability, damage, and growth in vitro.

The effect of gradually increased blood flow on ischemia-reperfusion injury in rat kidney.

Background: Gradually increased blood flow to the ischemic rat kidney was studied to assess the ability to diminish ischemia-reperfusion injury.

Methods: The left renal artery and vein were isolated in 25 rats. Microclamps were applied for 45 minutes and were released at once (group II) or gradually (group III).

Evaluation of 45S5 bioactive glass combined as a bone substitute in the reconstruction of critical size calvarial defects in rabbits.

Biomaterial research and tissue engineering have guided new developments in bone replacement. In this study, the osteoconductive and osteoinductive properties of 45S5 Bioglass (Novabone-C/M, Porex Surg., Newnan, GA), granules as a bone replacement material for large calvarial defects were evaluated.

Molecular markers in Paget disease of the breast.

Background And Objectives: Molecular markers are increasingly being analyzed in tumor specimens because of their relevance to both prognosis and choice of therapy. Paget disease of the breast is an uncommon form of breast cancer, in which molecular markers have not been well characterized. The objective of this study was to investigate the expression of c-erbB-2, p53, Ki-67, Cyclin D1, Bcl-2, estrogen receptors (ER), and progesterone receptors (PR) in mammary Paget disease.

Interferon alpha2b inhibits the murine melanoma cell line Cloudman S91 in vivo but not in vitro: a model for studying tumor cell-cytokine interactions.

Interferon alpha2b has recently been shown to improve outcome in patients with metastatic malignant melanoma. The high-dose interferon therapy used is however associated with significant systemic adverse effects. These adverse effects are likely related to the multitude of actions of interferon which in addition to its antineoplastic effects also possesses antiviral and immunomodulating properties.

Characterization of serum dehydroepiandrosterone secretion in golden hamsters.

Dehydroepiandrosterone (DHEA) is an adrenal androgen whose function is poorly understood. Although DHEA and DHEA sulfate (DHEAS) are secreted in relatively high quantities by the human adrenal, the laboratory rat secretes very little, thus hindering experimental studies of the hormone. In this paper, we measured the changes in serum DHEA and DHEAS under various physiological conditions in golden hamsters.

Dehydroepiandrosterone and exercise in golden hamsters.

Dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEAS) are adrenal androgens that have been associated with a sense of well-being in humans. We describe two experiments done to test the hypothesis that an increase in DHEA or DHEAS secretion is associated with the inclination to exercise using a hamster model. In the first experiment, morning blood samples were obtained from adult male golden hamsters at various intervals after being placed in cages with (EX group) or without (SED group) access to running wheels.

Does exercise affect female hamster gonadotropins by reducing estradiol negative feedback?

Exercise stimulates reproductive function in hamsters exposed to short-day photoperiod (SDP) in contrast to its inhibitory effects in women and rats. SDP inhibits hamster reproduction in part by increasing the sensitivity of the hypothalamo-pituitary-gonadal axis (HPGA) to the negative feedback of gonadal steroids. To determine whether EX facilitates reproduction in female hamsters by affecting this mechanism, we examined the influence of estradiol (E2) on basal LH and FSH concentrations in exercising and sedentary hamsters maintained on long-day photoperiod (LD 14:10, LDP) or SDP (LD 8:16).

Bromodeoxyuridine improves the cytotoxic effect of cisplatin: a comparison with 5-fluorouracil.

We compared the effects of the radiosensitizers, 5-bromo-2'-deoxyuridine (BUdR) and 5-fluorouracil (5-FU) alone and in combination and cis-diamminedichloroplatinum (cisplatin, DDP) on the growth of B16 amelanotic melanoma (B16a) tumors in mice. In a preliminary study, tumor growth was significantly inhibited in the presence of BUdR and was further reduced with the combination of BudR and DDP. In a second experiment, BUdR was found to be more effective than 5-FU when used in combination with DDP.

Decreased adrenal sex steroid levels in the absence of glucocorticoid suppression in postmenopausal asthmatic women.

Background And Aim: Reduction of serum sex steroid levels has been reported to occur after the administration of beta-adrenergic medication. In that beta-adrenergic blockade is a central pathophysiologic feature of asthma, this study was done to explore the possibility of hormonal alteration in asthma.

Methods: Sex steroids obtained from 22 postmenopausal asthmatic and 22 age-matched, postmenopausal, nonasthmatic women were assayed.

Voluntary exercise increases gonadotropin secretion in male Golden hamsters.

To determine the effect of voluntary exercise and food restriction on reproductive hormone secretion, 48 adult male hamsters were placed in cages with (EX) or without (SED) running wheels. One-half of the animals in each exercise group was fed ad libitum, and the other half was food restricted to reduce their body weight to 90 g over 4 wk. After 10 wk, the EX ad libitum-fed group had much larger testes and much higher serum follicle-stimulating hormone and testosterone levels than the other three groups, but these values in the EX food-restricted hamsters were similar to those in the SED food-restricted group.

Olfactory bulbectomy counteracts inhibitory effect of food restriction on reproductive function.

Previous studies have shown that bilateral removal of the olfactory bulbs (BX) results in a large increase in gonadotropin secretion in golden hamsters. The principal question addressed by the present study was whether BX would offset the inhibitory effect of food restriction on reproductive function. BX or sham (SH) BX male golden hamsters were fed ad libitum or were restricted to only enough food to maintain them at 70% of the body weight of control groups fed ad libitum.

Olfactory bulbectomy induces reproductive recrudescence in golden hamsters on short photoperiod.

Olfactory bulbectomy results in a marked increase in gonadotropin secretion and prevents the reproductive regression associated with short photoperiod when the olfactory bulbectomy is done before exposure to the inhibitory photoperiod. The present study tested whether olfactory bulbectomy would offset the influence of short photoperiod if done after the reproductive system had regressed. Adult golden hamsters Mesocricetus auratus were divided into four groups: early sham (surgery at week-4); early olfactory bulbectomy (surgery at week-4); late sham (surgery at week 14) and late olfactory bulbectomy (surgery at week 14).

Unilateral but not bilateral olfactory bulbectomy inhibits body weight gain in hamsters.

The relation of the olfactory bulbs and photoperiod to the regulation of body weight was studied in male golden hamsters. Animals underwent sham operation, bilateral olfactory bulbectomy, or unilateral bulbectomy. They were left on long photoperiod for 5 weeks and then were transferred to short photoperiod for 11 weeks.

Olfactory bulbectomy lengthens circadian period of locomotor activity in golden hamsters.

Removal of the olfactory bulbs (BX) of rats or mice lengthens the circadian period of locomotor activity. In golden hamsters, BX elevates serum gonadotropin levels of hamsters maintained in long or short photoperiod and prevents the testicular regression associated with short days without altering the secretion or action of pineal melatonin. The present study examined the influence of BX on circadian wheel-running activity in hamsters and tested whether this effect was related to changes in serum testosterone levels.

The olfactory bulbs enhance reproductive hormone secretion in male rats on long or short photoperiod.

Abstract Unlike seasonally breeding species such as the Syrian hamster, Sprague-Dawley laboratory rats do not normally respond to short photoperiod (6L18D) with reproductive regression. However, removal of the olfactory bulbs (BX) unmasks a photoperiodic response in pre-pubertal rats so that blinding or short photoperiod results in an inhibition of reproductive hormone secretion and/or a delay in pubertal development. This is apparently mediated by pineal melatonin which inhibits gonadotropin and/or prolactin secretion, but the mechanism by which BX facilitates the response to photoperiod is not clear.

The olfactory bulbs tonically inhibit serum gonadotropin and prolactin levels in male hamsters on long or short photoperiod.

Abstract Bilateral removal of the olfactory bulbs (BX) inhibits the testicular regression associated with maintenance of golden hamsters on short photoperiod (10L:14D). The present study was done to examine the reproductive endocrine changes following BX of hamsters, to test whether BX increases gonadotropin secretion by enhancing the rate of metabolism of peripheral testosterone, and to determine whether BX inhibits the response to photoperiod by blocking chemosensory signals from conspecifics. BX resulted in a marked increase in tonic serum gonadotropin levels in pre-pubertal (23 days old) and adult hamsters maintained on long photoperiod (14L:10D).

Bilateral transection of the lateral olfactory tract but not removal of the vomeronasal organs inhibits short-photoperiod-induced testicular regression in golden hamsters.

It is now known that removal of the olfactory bulbs increases basal gonadotropin secretion and prevents short-photoperiod-induced testicular regression in Syrian hamsters. The experiments described in the present paper were an attempt to determine which neuronal systems associated with the olfactory bulbs are responsible for this influence on the reproductive neuroendocrine axis. In the first experiment, removal of the vomeronasal organ failed to influence gonadotropin secretion or testes weight in hamsters on long or short photoperiod, suggesting that the vomeronasal-accessory olfactory pathway is not individually responsible for the effect of the olfactory bulbs on gonadotropin secretion.