The impact of gender on the nursing figure and nurses' interprofessional relationships: A multimethod study.

Aims: To identify the current presence of stereotypes about the nursing profession in Italy and to understand how gendered processes and modalities are regulated and expressed in the physician-nurse dyad, and the implications for professional identity and autonomy.

Design: Qualitative multimethod design.

Methods: Forty-five interviews were conducted with nurses and physicians.

Diagnostic and infection control strategies for Clostridioides difficile infections in a setting of high antimicrobial resistance prevalence.

Clostridioides difficile (CD) is a major nosocomial pathogen and the leading cause of antibiotic-associated diarrhoea. In light of the strong association between antimicrobial use and CD infections (CDI), it may be hypothesised that areas at higher prevalence of antimicrobial resistance, like the region of Campania in southern Italy, could also have a higher rate of CDI. In this multicentre, region-based, prospective study, we analysed such issues, exploiting CDI incidence data collected from local hospitals.

Serum depletion, multidrug resistance and fluorescent probes: methodological implications in free radicals evaluation.

Intracellular probes used for oxidative burst evaluation could be a substrate of the multidrug resistance proteins (MDR), which may cause misinterpretation of experimental data. We aimed to study the effect of the culture condition and of the MDR-interfering antioxidant quercetin on free radical measurement in serum depleted HCT-8 cells and chick embryo hepatocytes. Serum depletion and/or quercetin affected the traffic of 2',7'-bis(carboxyethyl)-5,6-carboxyfluorescein (BCECF) and calcein.

Chromosome fragility in river buffalo cows exposed to dioxins.

Fifty river buffalo (Bubalus bubalis, 2n = 50) cows reared in two different provinces of Campania (southern Italy) underwent cytogenetic investigations to ascertain possible differences in their chromosome stability. One group (Caserta province) was under legal sequestration due to the presence in the milk mass of higher mean values of dioxins [21.79 pg/g of fat as sum of polychloro-dibenzo-dioxins (PCDDs), polychloro-dibenzo-furans (PCDFs) and dioxin-like polychlorobiphenyls (DL-PCBs)] than both those permitted (6.

Hypertonic stress regulates amino acid transport and cell cycle proteins in chick embryo hepatocytes.

Hyperosmotic stress affects cell growth, decreasing cell volume and increasing the uptake of organic osmolytes. However, the sensitivity of embryonic cells to osmotic treatment remains to be established. We have analysed some aspects of cell-cycle control and amino-acid transport in hypertonic conditions during prenatal life.

Short-term effects of thyroid hormones during development: Focus on signal transduction.

Extranuclear or nongenomic effects of thyroid hormones are mediated by receptors located at the plasma membrane or inside cells, and are independent of protein synthesis. Recently the alphaVbeta3 integrin was identified as a cell membrane receptor for thyroid hormones, and a wide variety of nongenomic effects have now been shown to be induced through binding of thyroid hormones to this receptor. However, also other thyroid hormone receptors can produce nongenomic effects, including the cytoplasmic TRalpha and TRbeta receptors and probably also a G protein-coupled membrane receptor, and increasing importance is now given to thyroid hormone metabolites like 3,5-diiodothyronine and reverse T(3) that can mimick some nongenomic effects of T(3) and T(4).

Retrospective analysis of patients for development of nephrogenic systemic fibrosis following conventional angiography using gadolinium-based contrast agents.

Purpose: The purpose was to retrospectively review the data of 27 patients with renal insufficiency who underwent conventional angiography with gadolinium-based contrast agents (GDBCA) as alternative contrast agents and assess the occurrence of nephrogenic systemic fibrosis (NSF) together with associated potential risk factors.

Methods: This HIPAA-compliant study had institutional review board approval, and informed consent was waived. Statistical analysis was performed for all available laboratory and clinical data, including dermatology reports.

Short-term effects of thyroid hormones on Na+-K+-ATPase activity of chick embryo hepatocytes during development: focus on signal transduction.

Nongenomic effects of thyroid hormones on Na+-K+-ATPase activity were studied in chick embryo hepatocytes at two different developmental stages, 14 and 19 days of embryonal age, and the signal transduction pathways involved were characterized. Our data showed the following. 1) 3,5,3'-Triiodo-L-thyronine (T3) and 3,5-diiodo-L-thyronine (3,5-T2) rapidly induced a transient inhibitory effect on the Na+-K+-ATPase; the extent and duration depended on the developmental age of the cells.

Short-term effects of thyroid hormone in prenatal development and cell differentiation.

Extranuclear or nongenomic effects of thyroid hormones do not require interaction with the nuclear receptor, but are probably mediated by specific membrane receptors. This review will focus on the extranuclear effects of thyroid hormones on plasma membrane transport systems in non mammalian cells: chick embryo hepatocytes at two different stages of development, 14 and 19 days. At variance with mammals, the chick embryo develops in a closed compartment, beyond the influence of maternal endocrine factors.

Thyroid status affects rat liver regeneration after partial hepatectomy by regulating cell cycle and apoptosis.

In rats, various growth factors and hormones, as well as partial hepatectomy (PH) are able to trigger the proliferative response of hepatocytes. Although recent evidence highlights the important role of thyroid hormones and thyroid status in regulating the growth of liver cells in vitro and in vivo models, the mechanism involved in the pro-proliferative effects of thyroid hormones is still unclear. Here we have investigated how in rats made hypo- and hyperthyroid after prolonged treatment respectively with propylthiouracil (PTU) and triiodothyronine (T3), the thyroid status affects liver regeneration after PH by regulating cell cycle and apoptosis proteins.

Thyroid hormones regulate DNA-synthesis and cell-cycle proteins by activation of PKCalpha and p42/44 MAPK in chick embryo hepatocytes.

The molecular mechanism by which thyroid hormones exert their effects on cell growth is still unknown. In this study, we used chick embryo hepatocytes at different stages of development as a model to investigate the effect of the two thyroid hormones, T3 and T4, and of their metabolite T2, on the control of cell proliferation. We observed that T2 provokes increase of DNA-synthesis as well as T3 and T4, independently of developmental stage.

Treatment with EGF increases the length of S-Phase after partial hepatectomy in rat, changing the activities of cdks.

Liver proliferation occurs in the presence of mitogenic stimuli such as partial hepatectomy or growth factors. In this work we investigate how partial hepatectomy and Epidermal Growth Factor (EGF) affect hepatocyte proliferation by modulating cell cycle regulators. EGF administered to non-operated rats increased PCNA (proliferating cell nuclear antigen) expression, whereas when EGF was administered to partially hepatectomized rats it was able to anticipate the increase in PCNA expression to 18h after PH and to prolong it to 34h.

Short-term effects of thyroid hormones and 3,5-diiodothyronine on membrane transport systems in chick embryo hepatocytes.

Rapid nongenomic effects of thyroid hormones L-T(3) and L-T(4) on two plasma membrane transport systems were investigated in 14-d-old and 19-d-old chick embryo hepatocytes. The Na(+)/H(+) exchanger activity was measured using the intracellular pH-sensitive fluorescent probe 2',7'-bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein acetoxymethyl ester, whereas the amino acid transport was estimated by [1-(14)C]-2-aminoisobutyric acid uptake. System A amino acid transport activation was linear to hormone concentration, whereas the Na/H exchanger gave a bell-shaped dose-response curve, with a maximum at the physiological hormone concentration of 1 nM.

Mitogenic signal of epidermal growth factor in chick embryo hepatocytes: role of PKCalpha.

In the present study we investigated the role of two isoforms of protein kinase C in the mitogenic signal of epidermal growth factor (EGF) in primary culture of chick embryo hepatocytes. The down-regulation of PKCalpha by long-term exposure to phorbol myristate acetate (PMA) provoked a reduced mitogenic response to EGF while the down-regulation of PKCepsilon with oligonucleotide antisense had no effect on the stimulation of DNA synthesis, assayed as thymidine incorporation. EGF enhanced H3 diacylglycerol (DAG) production by cells preincubated with H3myristic acid, but did not increase the production of inositol 1-4-5-trisphosphate (IP3).

Epidermal growth factor regulates amino acid transport in chick embryo hepatocytes via protein kinase C.

System A-mediated amino acid transport, activation of different steps of signal transduction and involvement of different isoforms of protein kinase C (PKC) have been investigated in chick embryo hepatocytes after epidermal growth factor (EGF) stimulation. EGF rapidly (10 min) increased the rate of aminoisobutyric acid (AIB) uptake in chick embryo hepatocytes freshly isolated on the 19th day of embryonic life, while no change was detectable at other embryonal stages. The growth factor stimulation was abolished by PKC and tyrosine kinase inhibitors and was mimicked by 4-phorbol-12-myristate-13-acetate, dimethyl-2 (PMA).

How the ovarian follicle of Podarcis sicula recycles the DNA of its nurse, regressing follicle cells.

In Podarcis sicula specialized follicle cells send reserve materials to the previtellogenic oocyte via intercellular bridges. Immediately before the onset of vitellogenesis this transferring becomes particularly massive so that the cell volume significantly reduces, meanwhile in the nucleus the morphological alterations typical of apoptosis appear. To clarify why these follicle cells are not simply fully resorbed by the oocyte and to determine whether their DNA is discarded or recycled, we carried out a series of morphological and biochemical investigations.

EGF responsiveness of hepatocytes after partial hepatectomy.

We investigate the effect of EGF on IP3 production, PLC gamma phosphorylation, calcium transients in rat hepatocytes isolated in quiescent liver (G0 phase of cell cycle) and at 4 h (G1 phase of cell cycle) and 24 h (M phase of cell cycle) after partial hepatectomy. Our results show that EGF does not utilize IP3 and calcium as its signal transduction molecules when the hepatocytes are in vivo stimulated to entry in the cell cycle. In particular the growth factor does not phosphorylate PLC gamma and induces a decrease in IP3 content.

EGF modulation of Na+/H+ antiport in rat hepatocytes: different sensitivity in adult and fetal cells.

The modulation by epidermal growth factor (EGF) of the Na+/H+ antiport in fetal and adult rat hepatocytes was studied in nominally HCO3- free solution. EGF (10 nM) activated the antiport in adult rat hepatocytes by 0.22 +/- 0.

[Anhepatic rat, technic for reconstruction of venous circulation].

Authors report an experimental model of total hepatectomy in the rat. In this model whole liver was replaced by an autologous vascular prosthesis. On the contrary as reported in other experiences, in this model is maintained the cavo-caval flow, with absence of cavo-caval and porta-caval shunts.

Different signal transduction by epidermal growth factor may be responsible for the difference in modulation of amino acid transport between fetal and adult hepatocytes.

[1-14C]-2-aminoisobutyric acid (AIB) uptake and signal transduction pattern after epidermal growth factor (EGF) stimulation were examined in freshly isolated hepatocytes from 20-day-old fetuses and 3-month-old rats. EGF induced a transient increase of AIB transport after 10 min only in adult animals; the observed unresponsiveness of fetal liver is not dependent on a lack of EGF receptors which are present though to a lesser extent on the plasma membrane in this period. As far as the production of the second messengers, inositol trisphosphate (IP3) and calcium, is concerned, substantial differences were found: EGF increased IP3 production in adult hepatocytes, whereas it had no effect in fetal ones.

Intracellular signalling of epinephrine in rat hepatocytes during fetal development and hepatic regeneration.

The changes in intracellular calcium concentration and IP3 production after the addition of epinephrine were analysed in adult, fetal (20th-22nd day of intrauterine life), and regenerating rat hepatocytes (4 h-24 h after partial hepatectomy) to determine whether the signal transduction is the same in quiescent proliferating and differentiating cells. The epinephrine treatment causes a significative cytosolic calcium transient in hepatocytes isolated in the last day of fetal life (22-day old) and in the early stage of regeneration (4 h). This effect is not significant in the previous stage of fetal life (20-day old) and at the onset of M phase of cell cycle after partial hepatectomy (24 h).

Signal transduction during liver regeneration: role of insulin and vasopressin.

The relationship between cell proliferation and inositol lipid turnover has been studied by comparing the steady state of inositol derivative metabolism in quiescent and regenerating rat hepatocytes isolated at 4 h (G1 phase of first cell cycle) and 24 h (onset of M phase) after partial hepatectomy. The effect of two hormones able to regulate hepatic regeneration, insulin and vasopressin, has been considered, and the results can be summarized as follows: (i) at 4 h after partial hepatectomy, the precursor incorporation into inositol polyphosphates and the particulate phospholipase C activity increase with respect to quiescent hepatocytes, whereas the content of 11, 4, 5P3 does not change, suggesting an increased turnover of this molecule in this step of cell cycle priming; (ii) 24 h after partial hepatectomy, the radioactivity linked to IP3 and IP4, as well as soluble and particulate phospholipase C activity, and IP3 content increase, suggesting the presence, at the onset of M phase, of second messenger accumulation; (iii) only 24 h after partial hepatectomy, the inositol derivative metabolism is affected by vasopressin; and (iv) insulin exerts a modulatory role on inositol polyphosphate production without involving membrane-bound PLC activity or phosphoinositide hydrolysis. These data suggest that inositol-derived signal molecules are associated with hepatic regeneration; moreover, the metabolic pathway of such compounds seems to be regulated so that only specific inositol phosphates are present in each step of the cell cycle.

Amino acid uptake regulation by cell growth in cultured hepatocytes isolated from fetal and adult rats.

Amino acid uptake mediated by system A was studied in cultured fetal and adult hepatocytes, subjected to growth stimulation by EGF and insulin, or to growth inhibition by high cell density. The mitogenic stimulation induced a strong transport increase only in fetal cells, while the cell density-dependent growth inhibition, probably mediated by molecules present on adult hepatocyte membranes, provoked the decrease of amino acid uptake only in the adult cells. The results indicate that the different modulation of amino acid transport by cell growth is dependent on the age and the differentiation stage of hepatocytes.

Transglutaminase changes in intestinal mucosa after experimental small bowel resection in the rat.

The low serum transglutaminase found in various intestinal disorders (celiac disease and IBD) suggested to us to study the serum and mucosal transglutaminase behaviour in an experimental model of small intestine resection in rats to reduce cellular mass and induce enterocyte hyperproliferation in the proximal part left in continuity. Transglutaminase activity in the intestinal mucosa was significantly higher in resected rats than in control and sham operated animals from days 4 (121 +/- 10 v basal 94 +/- 3 mU/g protein, p < 0.01) to 10 (165 +/- 37 mU/g protein, p < 0.

Seasonal pattern of glycosylation in frog liver.

The circannual behaviour of glycosylation and protein synthesis in frog liver slices was studied following the incorporation of 3H-galactose and 14C-glucosamine into glycolipids and glycoproteins and 3H-leucine into proteins. The activity of two enzymes the galactosyl-transferase and the N-acetyl-glucosaminyl-1-P-transferase was determined. The incorporations of both sugars into the soluble fraction and into the lipid extract present a maximum during the spring-summer period.