Qualitative and quantitative change of the tolerance to liposomal amphotericin B triggered by biofilm maturation in C. parapsilosis.

Candida parapsilosis is an emerging opportunistic pathogen present in both clinical and natural environment, with a strong frequency of biofilm forming strains. While the drugs active against biofilm are rare, liposomal amphotericin B is credited with an antibiofilm activity in some opportunistic species of the genus Candida. Using freshly isolated strains from hospital environment, in this paper we could show the prevalence of biofilm forming vs. nonbiofilm forming strains. The former displayed a large variability in terms of biofilm biomass and metabolic activity. Liposomal amphotericin B minimum inhibitory concentration (MIC) of planktonic cells was below the breakpoint, whereas the sessile cells MIC (SMIC) was 1 or 2 orders of magnitude above the planktonic MIC. When the drug was applied to freshly attached cells, that is, biofilm in formation, the MIC (called SDMIC) was even below the MIC value. All resistance metrics (MIC, SMIC, and SDMIC) were quite variable although no correlation could be detected between them and the metrics used to quantify biofilm activity and biomass production. These findings demonstrate that young biofilm cells are even more susceptible than planktonic cells and that early treatments with this drug can be beneficial in cases of prosthesis implantation or especially when there is the necessity of a CVC reimplantation during a sepsis.

Office hysteroscopy in the management of women with postmenopausal bleeding.

Postmenopausal bleeding (PMB) is a relevant aspect for health-care providers in clinical practice: the first objective is to rule out potential gynecological cancer. The purpose of this narrative review is to evaluate the role of office hysteroscopy in the management of PMB. Office hysteroscopy is a minimally invasive procedure allowing direct visualization of uterine pathology without the need for general anesthesia and the use of an operating room, generating cost savings and greater compliance among patients. Here, we focus on major intrauterine diseases (polyps, submucosal myomas, endometrial hyperplasia, and cancer) as causes of PMB. Office hysteroscopy appears to be safe and feasible, and could allow accurate diagnosis of intrauterine pathologies, especially that with a focal growth pattern, otherwise misdiagnosed with blinded procedures. However, studies focusing exclusively on postmenopausal women are still few, so further research, especially randomized controlled trials, is needed.

Trabectedin for the therapy of ovarian cancer.

Trabectedin is a marine-derivate antitumor drug with a relevant cytotoxic activity and good safety profile. It has been investigated for the treatment of solid diseases, including ovarian cancer (OC), breast cancer, and soft-tissue sarcoma. In 2009, results from the pivotal trial OVA-301 led the European Medicines Agency (EMA) to the approval of trabectedin in combination with PEGylated liposomal doxorubicin for the treatment of platinum-sensitive recurrent OC; further studies revealed an additional benefit also in the subgroup of patients with partially platinum-sensitive disease and in those with a BRCA-mutated status. Additionally, trabectedin demonstrated to prolong the time interval to the subsequent chemotherapy line. Recently, the improved understanding of the antitumor action exerted by trabectedin paved the way to new investigational trials exploring its combination with targeted therapies.

Gestational diabetes mellitus: Prevention, diagnosis and treatment. A fresh look to a busy corner.

BACKGROUND: Gestational diabetes mellitus (GDM) is a common pregnancy complication characterized by hyperglycaemia with onset or first recognition during pregnancy. Risk factors include family history of diabetes, previous GDM, genetic predisposition for GDM/type 2 diabetes, insulin resistance conditions such as overweight, obesity and ethnicity. Women with GDM are at high risk for fetal macrosomia, small for gestational age, neonatal hypoglycaemia, operative delivery and caesarean delivery. The aim of this narrative review is to summarize the most recent findings of diagnosis and treatment of GDM in order to underline the importance to promote adequate prevention of this disease, especially through lifestyle interventions such as diet and physical activity. METHODS: The research was conducted using the following electronic databases, MEDLINE, EMBASE, Web of Science, Scopus, ClinicalTrial.gov, OVID and Cochrane Library, including all published randomized and non-randomized studies as well as narrative and systematic reviews. RESULTS: The lack of universally accepted criteria makes the definition of diagnosis and prognosis of this condition difficult. Early diagnosis and glucose blood level control may improve maternal and fetal short and long-term outcomes. Treatment strategies include nutritional interventions and exercise. Medical treatment can be necessary if these strategies are not effective. Moreover, novel non-pharmacologic agents such as myo-inositol seem to be effective and safe both in the prevention and the treatment of GDM. CONCLUSIONS: It is important to promote adequate prevention of GDM. Further studies are needed in order to better define the most appropriate strategies for the clinical management of women affected by GDM.

Self-organized criticality in sheared suspensions.

Recent studies reveal that suspensions of neutrally buoyant non-brownian particles driven by slow periodic shear can undergo a dynamical phase transition between a fluctuating irreversible steady state and an absorbing reversible state. Using a computer model, we show that such systems exhibit self-organized criticality when a finite particle sedimentation velocity v(s) is introduced. Under periodic shear, these systems evolve, without external intervention, towards the shear-dependent critical concentration phi(c) as v(s) is reduced. This state is characterized by power-law distributions in the lifetime and size of fluctuating clusters. Experiments exhibit similar behavior and, as v(s) is reduced, yield steady-state values of phi that tend towards the phi(c) corresponding to the applied shear.

Relugolix for the treatment of uterine fibroids.

Uterine leiomyomas represent the most common form of benign gynecological tumors affecting 20-40% of women during their life. Several therapeutic options are available for treating these patients. The use of medical treatment for myomas has largely grown in the last years, in particular for women who would refuse, postpone or are not candidates for surgery. In the last years, the clinical investigation of gonadotropin-releasing hormone (GnRH) antagonists (GnRH-ants) has emerged. This class of drugs exerts pure competitive antagonistic activity on the GnRH receptor at the pituitary gland, producing an immediate stop in the release of gonadotropins and sex steroids. Relugolix is an orally active nonpeptide GnRH-ant, recently licensed for marketing in Japan for the treatment of symptoms related to uterine myomas. Currently, several phase III clinical trials are ongoing to evaluate this molecule in this setting in the U.S. and Europe.

Management of Cesarean Scar Pregnancy: A Single-Institution Retrospective Review.

OBJECTIVE: Cesarean scar pregnancy (CSP) is a rare condition that occurs when the pregnancy implants in a cesarean scar. An early diagnosis and a proper management are fundamental to prevent maternal complications. We review and discuss the different treatment employed in our unit to reduce morbidity, preserve fertility, and predict possible complications. METHODS: The reported treatment has been expectant management, operative hysteroscopy approach, and intramuscular injection of 50 mg methotrexate (MTX), followed by cervical dilation and manual vacuum aspiration (D&S) with a Karman cannula under ultrasound guidance, uterine artery embolization (UAE), and manual vacuum aspiration under ultrasound guidance and uterine artery embolization before surgical laparotomic resection. RESULTS: Complications were more frequent in women with a history of three or more cesarean section deliveries and with a myometrial thickness thinner than 2 mm. MTX and D&S treatment appear to be most effective and safe at the early age of pregnancy, while UAE and D&S are related to the highest risk of complication in any age of pregnancy. CONCLUSION: An appropriate preoperative diagnostic evaluation, the identification of cases at higher risk, and those eligible for a conservative treatment are fundamental to reduce complications.

Design, characterization and in vivo performance of synthetic 2 mm-diameter vessel grafts made of PVA-gelatin blends.

Since the development of the first vascular grafts, fabrication of vessel replacements with diameters smaller than 6 mm remains a challenge. The present work aimed to develop PVA (poly (vinyl alcohol))-gelatin hybrids as tubes suitable for replacement of very small vessels and to evaluate their performance using a rat abdominal aorta interposition model. PVA-gelatin hybrid tubes with internal and external diameters of 1.4 mm and 1.8 mm, respectively, composed of 4 different gelatin ratios were prepared using a one-step strategy with both chemical and physical crosslinking. By 3D Time of Flight MRI, Doppler-Ultrasound, Computed Tomography angiography and histology, we demonstrated good patency rates with the 1% gelatin composition until the end of the study at 3 months (50% compared to 0% of PVA control grafts). A reduction of the patency rate during the time of implantation suggested some loss of properties of the hybrid material in vivo, further confirmed by mechanical evaluation until one year. In particular, stiffening and reduction of compliance of the PVA-gelatin grafts was demonstrated, which might explain the observed long-term changes in patency rate. These encouraging results confirm the potential of PVA-gelatin hybrids as ready-to-use vascular grafts for very small vessel replacement.

High-contrast Brillouin and Raman micro-spectroscopy for simultaneous mechanical and chemical investigation of microbial biofilms.

Mechanical mapping with chemical specificity of biological samples is now made possible by joint micro-Brillouin and micro-Raman measurements. In this work, thanks to the unprecedented contrast of a new tandem Fabry-Perot interferometer, we demonstrate simultaneous detection of Brillouin and Raman spectra from different Candida biofilms. Our proof-of-concept study reveals the potential of this label-free joint micro-spectroscopy technique in challenging microbiological issues. In particular, heterogeneous chemo-mechanical maps of Candida biofilms are obtained, without the need for staining or touching the sample. The correlative Raman and Brillouin investigation evidences the role of both extracellular polymeric substances and of hydration water in inducing a marked local softening of the biofilm.

Inhibition of acetylcholine-induced activation of extracellular regulated protein kinase prevents the encoding of an inhibitory avoidance response in the rat.

It has been demonstrated that the forebrain cholinergic system and the extracellular regulated kinase signal transduction pathway are involved in the mechanisms of learning, encoding, and storage of information. We investigated the involvement of the cholinergic and glutamatergic systems projecting to the medial prefrontal cortex and ventral hippocampus and of the extracellular regulated kinase signal transduction pathway in the acquisition and recall of the step-down inhibitory avoidance response in the rat, a relatively simple behavioral test acquired in a one-trial session. To this aim we studied by microdialysis the release of acetylcholine and glutamate, and by immunohistochemistry the activation of extracellular regulated kinase during acquisition, encoding and recall of the behavior. Cholinergic, but not glutamatergic, neurons projecting to the medial prefrontal cortex and ventral hippocampus were activated during acquisition of the task, as shown by increase in cortical and hippocampal acetylcholine release. Released acetylcholine in turn activated extracellular regulated kinase in neurons located in the target structures, since the muscarinic receptor antagonist scopolamine blocked extracellular regulated kinase activation. Both increased acetylcholine release and extracellular regulated kinase activation were necessary for memory formation, as administration of scopolamine and of extracellular regulated kinase inhibitors was followed by blockade of extracellular regulated kinase activation and amnesia. Our data indicate that a critical function of the learning-associated increase in acetylcholine release is to promote the activation of the extracellular regulated kinase signal transduction pathway and help understanding the role of these systems in the encoding of an inhibitory avoidance memory.

In vivo amino acid release from the striatum of aging rats: adenosine modulation.

The release of glutamate, aspartate, GABA, and taurine from the striatum of young (3 months), mature (12 months), and old (22 months), freely moving male rats was investigated by using a microdialysis fiber inserted transversally in the striatum. In old rats basal extracellular glutamate and aspartate levels were decreased vs. young rats (-38 and -49%, respectively). GABA and taurine levels were unmodified by age. In the presence of the adenosine receptor antagonist 8-phenyltheophilline (8-pT) at the concentration of 50 microM, both K(+)-evoked releases of glutamate and aspartate were more than doubled in young, but not in mature and old rats. 8-pT at the concentration of 500 microM significantly decreased glutamate basal levels and K(+)-evoked aspartate release in old rats only. GABA and taurine releases were not affected by 8-pT at either dose. Our findings indicate a modified adenosine modulation on glutamate and aspartate release in aged rats, that could result from a change in the balance between A1 and A2a adenosine receptor density or an alteration of A1 and A2a receptor-effector coupling.

Sites of [3H]taurine Uptake in the Rat Substantia Nigra in Relation to the Release of Taurine from the Striatonigral Pathway.

The autoradiographic localization of radiolabelled taurine taken up in the rat substantia nigra in vivo together with conditions of release of the [3H]taurine taken up into brain slices were studied to determine whether they are consistent with the hypothesis that taurine may act as a neurotransmitter in the striatonigral pathway. At the light microscopic level the main cellular elements that became radiolabelled following the injection of [3H]taurine into the substantia nigra could be identified as glial cells. Electron microscope autoradiography confirmed that a subpopulation of glial cells including astrocytes, pericytes, and oligodendrocytes were radiolabelled and that neuronal perikarya were not radiolabelled. In addition, axonal elements including both terminal and preterminal boutons were found to have silver grains overlying them and were thus considered to be radiolabelled. This was supported by a quantitative analysis of the distribution of the silver grains; whereas glial elements had a significantly higher number of grains associated with them than with any other structure, axonal elements had a significantly greater number of grains than dendritic structures. Release of the preloaded [3H]taurine from superfused slices of substantia nigra occurred in response to veratridine, was calcium-dependent and was sensitive to inhibition by high magnesium concentrations or tetrodotoxin. Following the destruction of neurons in the striatum by ibotenic acid injections, although the weight of the ipsilateral substantia nigra was reduced, the uptake of [3H]taurine was not altered. In contrast to this, the veratridine-stimulated release was markedly attenuated, implying that the destruction of striatal neurons causes the loss of sites in the substantia nigra from which exogenous taurine is released. These results add further support to previous suggestions that taurine might act as a neurotransmitter or neuromodulator in the striatonigral pathway.

The release of amino acids from rat neostriatum and substantia nigra in vivo: a dual microdialysis probe analysis.

It has previously been demonstrated, in dual probe microdialysis studies, that stimulation of the neostriatum with kainic acid causes the release of GABA both locally within the neostriatum and distally in the substantia nigra, observations that are consistent with the known anatomy of the basal ganglia. The object of the present study was to further examine the characteristics of GABA release and to determine whether taurine, which has been proposed to be present in striatonigral neurons, has similar characteristics of release, and to examine the release of excitatory amino acids under the same conditions. To this end, dual probe microdialysis studies were carried out on freely-moving rats. The application of kainic acid to neostriatum enhanced the release of GABA, taurine, aspartate and glutamate locally in the neostriatum and distally in the substantia nigra. The distal release of each amino acid in the substantia nigra was sensitive to the administration of 6,7-dinitroquinoxaline-2,3-dione and tetrodotoxin to the neostriatum. Similarly the local release of GABA, aspartate and glutamate but not taurine was sensitive to the intrastriatal application of 6,7-dinitroquinoxaline-2,3-dione or tetrodotoxin. It is concluded that the release of taurine from the substantia nigra has similar characteristics to that of GABA and may be released from the terminals of striatonigral neurons following the stimulation of their cell bodies in the neostriatum. The release of taurine in the neostriatum however, is likely to be mediated mainly by different mechanisms and not related to neuronal activity. The release of excitatory amino acids is likely to involve indirect effects in the neostriatum and polysynaptic pathways in the substantia nigra.

Neurotensin modulation of acetylcholine and GABA release from the rat hippocampus: an in vivo microdialysis study.

The effects of neurotensin (NT) on the release of acetylcholine (ACh), aspartate (Asp), glutamate (Glu) and gamma-aminobutyric acid (GABA) from the hippocampus of freely moving rats were studied by transversal microdialysis. ACh was detected by High Performance Liquid Chromatography (HPLC) with electrochemical detection while GABA, glutamate and aspartate were measured using HPLC with fluorometric detection. Neurotensin (0.2 and 0.5 microM) administered locally through the microdialysis probe to the hippocampus produced a long-lasting and concentration-dependent increase in the basal extracellular levels of GABA and ACh but not of glutamate and aspartate. The increase in the extracellular levels of GABA and ACh produced by 0.5 microM neurotensin in the hippocampus reached a maximum of about 310% for GABA and 250% for ACh. This stimulant effect of NT was antagonized by the NT receptor antagonist SR 48692 (100 microg/kg, i.p.). Local infusion of tetrodotoxin (1 microM) decreased the basal release of ACh, GABA, Asp, Glu and prevented the 0.2 microM NT-induced increase in GABA and ACh release. The effect of NT on the release of ACh was blocked by the GABA(A) receptor antagonist bicuculline (2-10 microM). Our findings indicate for the first time that neurotensin plays a neuromodulatory role in the regulation of GABAergic and cholinergic neuronal activity in the hippocampus of awake and freely moving rats. The potentiating effects of neurotensin on GABA and ACh release in the hippocampus are probably mediated by (i) NT receptors located on GABAergic cell bodies and (ii) through GABA(A) receptors located on cholinergic nerve terminals.

The effect of kainic acid on the release of GABA in rat neostriatum and substantia nigra.

In order to test the hypotheses that stimulation of non-N-methyl-D-aspartate (NMDA) receptors in the neostriatum causes the release of gamma-aminobutyric acid (GABA) from nigrostriatal neurones, dual microdialysis was carried out in the neostriatum and substantia nigra of freely moving rats. Application of kainic acid to the neostriatum caused a dose-dependent release of GABA both locally and, at the same time, from the ipsilateral substantia nigra. These effects were blocked by the non-NMDA receptor antagonist 6,7-dinitroquinoxaline-2,3-dione (DNQX). Direct application of kainic acid to the substantia nigra caused a DNQX-sensitive local release of GABA. It is concluded that excitatory amino acid receptor stimulation of the neostriatum releases GABA from striatonigral neurones and that stimulation of the substantia nigra causes the release from striatonigral terminals and/or the collaterals of nigrofugal neurones.

Activation of non-NMDA receptors stimulates acetylcholine and GABA release from dorsal hippocampus: a microdialysis study in the rat.

The effect of the non-N-methyl-D-aspartate (NMDA) agonists (RS)-alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) and quisqualate (QUIS) on the release of acetylcholine (ACh), gamma-amino butyric acid (GABA), aspartate (Asp) and glutamate (Glu) from the hippocampus of freely moving rats was studied by transversal microdialysis. Intracerebroventricular (i.c.v.) administration of the non-NMDA receptor agonist AMPA (0.5 nmol) enhanced (by about 200%) ACh release from the hippocampus. The effect of AMPA was completely antagonized by 6-nitro-7-sulphamoyl-benz(f)quinoxaline-2,3-dione (NBQX; 2 nmol, i.c.v). No effect was seen when AMPA was perfused through the septum. However, AMPA (200 microM) locally applied to the hippocampus, increased (by about 200%) ACh release. QUIS (200 microM) applied locally to the hippocampus produced a long-lasting increase in the release of ACh (by about 215%) and GABA (by about 460%). Local infusion of tetrodotoxin (1 microM) decreased ACh and GABA basal extracellular levels, and abolished the QUIS-induced increase in ACh and GABA. Our results demonstrate that non-NMDA glutamatergic receptors in the hippocampus regulate hippocampal release of GABA and ACh.

Complexities in the neurotoxic actions of 6-hydroxydopamine in relation to the cytoprotective properties of taurine.

The neurotoxin 6-hydroxydopamine was shown to cause an imbalance between the direct and indirect pathways of the striato-nigral system as evidenced by a decreased release of gamma-aminobutyric acid and taurine in the substantia nigra but not in the globus pallidus following neostriatal stimulation with kainate (100 microM). The neurotoxicity of 6-hydroxydopamine is generally believed to result from reactive-oxygen radical formation, although it is also known to inhibit mitochondrial NADH dehydrogenase. The release of Fe(II) from the unactivated form [3Fe(III)-4S] of cytoplasmic aconitase (EC(50) < 8 microM) was shown to be followed by the slower oxidation of thiol groups in the protein. Complete loss of -SH groups, and enzyme activity, was seen after incubation of glyceraldenyde-3-phosphate dehydrogenase with 200 microM 6-hydroxydopamine for 75 min at 37 degrees C (IC(50) = 70.8 +/- 0.3 microM). Thus the cellular effects of 6-hydroxydopamine are complex, involving impairment of mitochondrial function, iron- release, sulphydryl-group oxidation, and enzyme inhibition in addition to direct generation of reactive oxygen radicals. Taurine, which is known to be neuroprotective in some other systems, only affords protection against some of these effects, thereby explaining its reported ineffectiveness against 6-hydroxydopamine toxicity.

The effects of ethanol on rat brain monoamine oxidase activities.

In contrast to the reported behaviour of human platelet MAO-B, chronic ethanol feeding does not significantly affect the sensitivities of either MAO-A or -B from rat brain to inhibition by ethanol in vitro. The thermal stabilities of rat brain MAO-A and -B are not significantly affected by chronic ethanol feeding.

The influence of adrenalectomy on monoamine oxidase and NADH cytochrome c reductase in the rat heart.

The effect of adrenalectomy on the activities of monoamine oxidase (MAO), NADH cytochrome c reductase (NCR), succinate dehydrogenase, malate dehydrogenase, fumarase, NAD+ nucleosidase and acid phosphatase in homogenates of rat hearts was examined. Besides MAO only the NCR activity increased. However, both the total and the rotenone-insensitive NCR activities increased, with that of the rotenone-insensitive being about half of the total, which indicated that the effect of adrenalectomy was exerted on components of this enzyme localized on both the inner and outer membranes of the mitochondrion. The lack of effect on the other enzymes suggests that adrenalectomy has a relatively selective action on MAO and NCR, and does not work by a generalized increase in protein synthesis or by an effect on the FAD cofactor. The MAO increase was seen with a variety of substrates, and was due to a rise in Vmax without change in Km. The response to adrenalectomy in the summer differed from that seen in the winter. The possible reasons for these effects of adrenalectomy are discussed.

Pharmacokinetics of chlorimipramine, chlorpromazine and their N-dealkylated metabolites in plasma of healthy volunteers after a single oral dose of the parent compounds.

A single oral dose of 0.7 mg kg-1 chlorimipramine (n = 18) and chlorpromazine (n = 16) was given to each subject 45 days apart and plasma concentrations of parent drugs and their monodesmethyl and didesmethyl metabolites were measured by GC. Ingestion of chlorimipramine resulted in an area under the plasma concentration-time curve (AUC0-24) for parent drug plus metabolites 5-fold higher than that observed in the same subjects following chlorpromazine intake (600 +/- 87 and 124 +/- 14 ng mL-1, respectively). Plasma chlorimipramine levels reached a mean peak value of 43.8 ng mL-1, which occurred 2 h after administration. Desmethyl metabolite kinetics of chlorimipramine appeared to be elimination rate-limited and those of chlorpromazine appeared to be formation-rate-limited. The response to single doses of these two drugs in healthy subjects highlights the two distinct dispositional processes involved, thus offering pharmacokinetic explanation of the hitherto empirical discrepancy in dosage levels in chronic treatment.