A 72-h intervention for improvement of the rate of optimal antibiotic therapy in patients with bloodstream infections.

Antimicrobial stewardship programs are implemented to optimize the use of antibiotics and control the spread of antibiotic resistance. Many antimicrobial stewardship interventions have demonstrated significant efficacy in reducing unnecessary prescriptions of antibiotics, the duration of antimicrobial therapy, and mortality. We evaluated the benefits of a combination of rapid diagnostic tests and an active re-evaluation of antibiotic therapy 72 h after the onset of bloodstream infection (BSI). All patients with BSI from November 2015 to November 2016 in a 1100-bed university hospital in Rome, where an Infectious Disease Consultancy Unit (Unità di Consulenza Infettivologica, UDCI) is available, were re-evaluated at the bedside 72 h after starting antimicrobial therapy and compared to two pre-intervention periods: the UDCI was called by the ward physician for patients with BSI and the UDCI was called directly by the microbiologist immediately after a pathogen was isolated from blood cultures. Recommendations for antibiotic de-escalation or discontinuation significantly increased (54%) from the two pre-intervention periods (32% and 27.2%, p < 0.0001). Appropriate escalation also significantly increased (22.5%) from the pre-intervention periods (8.1% and 8.2%, p < 0.0001). The total duration of antibiotic therapy decreased with intervention (from 21.9 days [standard deviation, SD 15.4] in period 1 to 19.3 days [SD 13.3] in period 2 to 17.7 days in period 3 [SD 11.5]; p = 0.002) and the length of stay was significantly shorter (from 29.7 days [SD 29.3] in period 1 to 26.8 days [SD 24.7] in period 2 to 24.2 days in period 3 [SD 20.7]; p = 0.04) than in the two pre-intervention periods. Mortality was similar among the study periods (31 patients died in period 1 (15.7%), 39 (16.7%) in period 2, and 48 (15.3%) in period 3; p = 0.90). Rapid diagnostic tests and 72 h re-evaluation of empirical therapy for BSI significantly correlated with an improved rate of optimal antibiotic therapy and decreased duration of antibiotic therapy and length of stay.

Cell proliferation and drug sensitivity of human glioblastoma cells are altered by the stable modulation of cytosolic 5'-nucleotidase II.

Cytosolic 5'-nucleotidase II (cN-II) has been reported to be involved in cell survival, nucleotide metabolism and in the cellular response to anticancer drugs. With the aim to further evaluate the role of this enzyme in cell biology, we stably modulated its expression the human glioblastoma cell ADF in which the transient inhibition of cN-II has been shown to induce cell death. Stable cell lines were obtained both with inhibition, obtained with plasmids coding cN-II-targeting short hairpin RNA, and stimulation, obtained with plasmids coding Green Fluorescence Protein (GFP)-fused wild type cN-II or a GFP-fused hyperactive mutant (GFP-cN-II-R367Q), of cN-II expression. Silenced cells displayed a decreased proliferation rate while the over expressing cell lines displayed an increased proliferation rate as evidenced by impedance measurement using the xCELLigence device. The expression of nucleotide metabolism relevant genes was only slightly different between cell lines, suggesting a compensatory mechanism in transfected cells. Cells with decreased cN-II expression were resistant to the nucleoside analog fludarabine confirming the involvement of cN-II in the metabolism of this drug. Finally, we observed sensitivity to cisplatin in cN-II silenced cells and resistance to this same drug in cN-II over-expressing cells indicating an involvement of cN-II in the mechanism of action of platinum derivatives, and most probably in DNA repair. In summary, our findings confirm some previous data on the role of cN-II in the sensitivity of cancer cells to cancer drugs, and suggest its involvement in other cellular phenomenon such as cell proliferation.

The purine analog fludarabine acts as a cytosolic 5'-nucleotidase II inhibitor.

For several years the IMP/GMP-preferring cytosolic 5'-nucleotidase II (cN-II) has been considered as a therapeutic target in oncology. Indeed, various reports have indicated associations between cN-II expression level and resistance to anticancer agents in several cancer cell lines and in patients affected with neoplasia, mainly by hematologic malignancies. In this paper we present evidence showing that, among the commonly used cytotoxic nucleoside analogs, fludarabine can act as a cN-II inhibitor. In vitro studies using the wild type recombinant cN-II demonstrated that fludarabine inhibited enzymatic activity in a mixed manner (Ki 0.5 mM and Ki' 9 mM), whereas no inhibition was observed with clofarabine and cladribine. Additional experiments with mutant recombinant proteins and an in silico molecular docking indicated that this inhibition is due to an interaction with a regulatory site of cN-II known to interact with adenylic compounds. Moreover, synergy experiments between fludarabine and 6-mercaptopurine in human follicular lymphoma (RL) and human acute promyelocytic leukemia (HL-60) cells transfected with control or cN-II-targeting shRNA-encoding plasmids, showed synergy in control cells and antagonism in cells with decreased cN-II expression. This is in line with the hypothesis that fludarabine acts as a cN-II inhibitor and supports the idea of using cN-II inhibitors in association with other drugs to increase their therapeutic effect and decrease their resistance.

Thyroid hormones and the cardiovascular system: pathophysiology and interventions.

Thyroid dysfunction, however mild, can significantly affect the cardiovascular (CV) system. The effects of thyroid hormones may be viewed as genomic and non-genomic, with the former occurring over a longer time scale and both affecting structural and functional proteins in CV tissue. As the interplay between thyroid function and the CV system becomes elucidated, particularly in the context of a system biology approach, the heart failure phenotype is better understood. Symptomatology is related to disturbance in inotropic and chronotropic function. Moreover, biochemical changes reflected by thyroid function testing with the non-thyroidal illness syndrome can prognosticate and guide therapy in heart failure. In addition, empiric treatment with thyroid hormone analogues or T3 represent emergent and highly controversial interventions.

5 '-Amino-4-imidazolecarboxamide riboside induces apoptosis in human neuroblastoma cells via the mitochondrial pathway.

5'-Amino-4-imidazolecarboxamide (AICA) riboside induces apoptosis in neuronal cell models. In order to exert its effect, AICA riboside must enter the cell and be phosphorylated to the ribotide. In the present work, we have further studied the mechanism of apoptosis induced by AICA riboside. The results demonstrate that AICA riboside activates AMP-dependent protein kinase (AMPK), induces release of cytochrome c from mitochondria and activation of caspase 9. The role of AMPK in determining cell fate is controversial. In fact, AICA riboside has been reported to be neuroprotective or to induce apoptosis depending on its concentration, cell type or apoptotic stimuli used. In order to clarify whether the activation of AMPK is related to apoptosis in our model, we have used another AMPK stimulator, metformin, and we have analysed its effects on cell viability, nuclear morphology and AMPK activity. Five mM metformin increased AMPK activity, inhibited viability, and increased the number of apoptotic nuclei. AICA riboside, which can be generated from the ribotide (an intermediate of the purine de novo synthesis) by the action of the ubiquitous cytosolic 5'-nucleotidase (cN-II), may accumulate in those individuals in which an inborn error of purine metabolism causes both a building up of intermediates and/or an increase of the rate of de novo synthesis, and/or an overexpression of cN-II. Therefore, our results suggest that the toxic effect of AICA riboside on some types of neurons may participate in the neurological manifestations of syndromes related to purine dismetabolisms.

Renoprotective effect of renin-angiotensin system block: what has happened?

The Renin Angiotensin System block achieved by current available therapy (angiotensin II antagonism), despite undoubted beneficial effects, is associated to a persistent cardiovascular and renal mortality. During this angiotensin II antagonism, Renin Angiotensin System block is incomplete and angiotensin II break through. The Author analyses possible etiopathogenetic factors. Renin inhibition and Angiotensin-Converting Enzyme type 2 modulation are indicated and discussed as opportunities of Renin Angiotensin System block other than Angiotensin-Converting Enzyme inhibitors and Angiotensin Receptor Blockers, that may render the Renin Angiotensin System block more quiescient.

[Brain natriuretic peptide and heart failure]. / Peptide natriuretico cerebrale e insufficienza cardiaca.

Heart failure is analysed following the recent classification (prognostic and symptomatic: 4 stages) proposed by the American Heart Association (AHA). The study is focused on the first stage (Stage A) of the AHA classification where the patient is asymptomatic, without heart structural abnormalities but at risk to develop heart failure. In Stage A neurohumural mechanisms of heart failure such as natriuretic peptide system are activated. The author analyses the links between heart failure and the natriuretic peptide system and the role played by the plasma level of brain natriuretic peptide as biomarker of heart failure in Stage A.

[Functional renal reserve and glomerular hyperfiltration]. / Riserva funzionale renale e iperfiltrazione glomerulare.

The hemodynamic theory of progressive renal disease with glomerular hyperfiltration has been proposed as common final pathway of kidney disease progression. The evaluation of renal functional reserve is an useful approach to point out glomerular hyperfiltration. First the author describes the meaning of renal functional reserve, mechanisms of glomerular hemodynamic regulation and renal reaction to proteic load and finally explains the practical application of renal functional reserve in clinical nephrology.

Identification of the 5'-nucleotidase activity altered in neurological syndromes.

5'-Nucleotidases comprise a family of enzymes involved in the regulation of intracellular and extracellular nucleotide concentration. There is increasing knowledge about an involvement of these activities in the aetiology of neurological disorders. In this paper we present a protocol for the identification of the altered enzyme in fibroblasts primary culture from patients and controls.

[Lipoprotein-associated phospholipase A2: importance and perspectives]. / Fosfolipase A2 associata alle lipoproteine. Significato e prospettive.

Type VII phospholipase A2 associated to low density lipoproteins (LDL), also known as platelet-activating factor acetylhydrolase, has been recently indicated as a new non traditional and independent risk factor of coronary disease. After the classification of phospholipase A2 family enzymes, a review is made of the recent physiologic and biochemical knowledges on A2 type VII phospholipase LDL lipoproteins-associated and the role developed in lipoproteins metabolism and atherogenesis. Finally, future therapeutic implications and perspectives depending on these knowledges are pointed out especially by using molecules inhibiting the activity of the enzyme in atherosclerosis therapy. The evaluation of circulating activity of the enzyme may be useful in the prevention and recognition of acute coronary syndromes.

[Prostate cancer and prostate specific antigen screening]. / Cancro prostatico e screening con test PSA.

Prostate cancer diagnosis by prostate specific antigen (PSA) test is so popular and widespread that becomes a routine mass screening. The screening efficacy has not yet been proved and today remains a controversial topic. The author discusses about present arguments in support and in opposite to the use of PSA screening. Waiting for definitive results of the efficacy of PSA screening from randomised trials, the author shows what may be useful to do in clinical routinary practice with PSA test. Since PSA is tissue specific and not cancer specific, very often further unnecessary investigations such as prostate biopsy are required. To reduce false positive and false negative results of the PSA test and to indicate which men with negative prostate biopsy need rebiopsy, new methods improving specificity and sensibility of PSA test have been proposed. To clarify these improving PSA test methods, the author analyses each method showing limits and performances. New molecular forms of PSA (PSA isoforms) circulating in peripheral blood are also evaluated.

[Death of Napoleon Bonaparte]. / Morte di Napoleone Bonaparte.

The causa mortis of Napoleon Bonaparte has been vexata quaestio for a long time. The author tries to outline a picture of Napoleon from a sanitary point of view. From the report of doctor Francesco Antonmarchi who performed the autopsy, the author tries to understans the cause of death: gastric perforation due to malignant ulcer and subsequent peritonitis with pulmonary tubercolosis.

5'-aminoimidazole-4-carboxamide riboside induces apoptosis in human neuroblastoma cells.

5'-Aminoimidazole-4-carboxamide riboside (AICA riboside) has been previously shown to be toxic to two neuronal cell models [Neuroreport 11 (2000) 1827]. In this paper we demonstrate that AICA riboside promotes apoptosis in undifferentiated human neuroblastoma cells (SH-SY5Y), inducing a raise in caspase-3 activity. In order to exert its effect on viability, AICA riboside must enter the cells and be phosphorylated to the ribotide, since both a nucleoside transport inhibitor, and an inhibitor of adenosine kinase produce an enhancement of the viability of AICA riboside-treated cells. Short-term incubations (2 h) with AICA riboside result in five-fold increase in the activity of AMP-dependent protein kinase (AMPK). However, the activity of AMPK is not significantly affected at prolonged incubations (48 h), when the apoptotic effect of AICA riboside is evident. The results demonstrate that when the cell line is induced to differentiate both toward a cholinergic phenotype (with retinoic acid) or a noradrenergic phenotype (with phorbol esters), the toxic effect is significantly reduced, and in the case of the noradrenergic phenotype differentiation, the riboside is completely ineffective in promoting apoptosis. This reduction of effect correlates with an overexpression of Bcl-2 during differentiation. AICA riboside, derived from the hydrolysis of the ribotide, an intermediate of purine de novo synthesis, is absent in normal healthy cells; however it may accumulate in those individuals in which an inborn error of purine metabolism causes an increase in the rate of de novo synthesis and/or an overexpression of cytosolic 5'-nucleotidase, that appears to be the enzyme responsible for AICA ribotide hydrolysis. In fact, 5'-nucleotidase activity has been shown to increase in patients affected by Lesch-Nyhan syndrome in which both acceleration of de novo synthesis and accumulation of AICA ribotide has been described, and also in other neurological disorders of unknown etiology. Our results raise the intriguing clue that the neurotoxic effect of AICA riboside on the developing brain might contribute to the neurological manifestations of syndromes related to purine dismetabolisms.

[Cardiovascular prevention: new biochemical plasmatic markers of risk]. / Prevenzione cardiovascolare. Nuovi indici biochimici plasmatici di rischio.

The primary prevention of acute coronary syndromes is an open question. The scientific progress has discovered new biochemical markers of cardiovascular disease risk that may be useful for primary prevention. They are plasmatic markers of inflammation (serum amyloid A, C-reactive protein, phospholipase A2) and of infection (seropositivity to Chlamydia pneumoniae, cytomegalovirus). They are plasmatic markers of endothelial activation (adhesion molecules such as ICAM-1, VCAM-1) immunological markers (autoantibodies against oxydized LDL, hemostatic markers (TFPI, PAI-1) and metabolic indices (Lpa, homocystein). A gap is evident between the scientific progress in the knowledge of the epidemiology of cardiovascular pathology and its application in clinical practice. The priority should become the population approach to primary prevention: the rapidly changing and complex global context presents new challenges for public health practitioners struggling to implement preventive policies and programmes. New risk factors of cardiovascular disease have been pointed out by research. This study shows the situation on the topic with critique and updated analysis.

[Vomiting]. / Il vomito.

Vomiting, the culminating sign of nausea, is primarily a protective reflex occurring in a wide variety of vertebrates. Even tough nausea and vomiting are among the most basic neural reflexes, they remain poorly understood. Poorly understood are the pathogenetic mechanisms from the anatomic receptor and neuroendocrine point of view. This is the reason why drugs are useful in some types of vomiting but not in others. The aim of this paper is to summarize current knowledge about anatomy of vomiting reflex, neurotransmitter receptor subtypes, agonists and antagonists of serotonin and substance P. Particularly in the treatment of post-chemotherapy and postoperative vomiting. It is pointed out that nausea an vomiting may be field of neurochemical and neuropharmacological research. Finally, in clinical research drugs for vomiting therapy may be useful in other pathologies (migraine, rheumatoid arthritis, bronchial asthma).

C-reactive protein, atherosclerosis and cardiovascular disease. An update.

Recent epidemiological data have documented associations between C-reactive protein (CRP), the prototypical acute phase response protein, and cardiovascular disease in general population. Given the lipoprotein binding and complement activation of CRP and its localization in atherosclerotic vessels, there is a strong likelihood that CRP may be involved in the atherosclerotic process. Statin therapy seems to have action anti-atherosclerosis by inhibiting vascular atherosclerotic inflammation: clinical trials are needed. This review would be an update on the topic.

Catabolism of exogenous deoxyinosine in cultured epithelial amniotic cells.

Uptake and catabolism of purine nucleosides have been commonly considered as means to salvage the purine ring for nucleic acid synthesis, usually neglecting the destiny of the pentose moiety. With the aim to ascertain if deoxyribose derived from exogenous DNA can be utilised as a carbon and energy source, we studied the catabolism of exogenous deoxyinosine in a cell line derived from human amnion epithelium (WISH). Intact WISH cells catabolise deoxyinosine by conversion into hypoxanthine. The nucleoside enters the cell through a nitrobenzylthioinosine-insensitive equilibrative transport. Deoxyinosine undergoes a phosphorolytic cleavage inside the cell. The purine base diffuses back to the external medium, while the phosphorylated pentose moiety can be further catabolised to glycolysis and citric acid cycle intermediates. Our results indicate that the catabolism of the deoxynucleoside can be considered mainly as a means to meet the carbon and energy requirements of growing cells.

Plasma platelet activating factor in nephrotic syndrome.

BACKGROUND: The mechanism of proteinuria in nephrotic syndrome is unknown. The plasma behaviour of platelet-activating factor (ng/ml) in nephrotic and normal people has been evaluated. METHODS: A total of 21 patients with nephrotic proteinuria due to glomerular pathology and 20 subjects as normal control people have been studied. Plasma PAF level is evaluated by ((125)I) RIA Kit (Du Pont NEN). RESULTS: Patients with glomerular proteinuria appeared to have a significant increase (p<0.05) plasma PAF bioactivity: 116.28+/-49.6 ng/ml versus 41.4+/-14.9 ng/ml of normal subjects. CONCLUSIONS: The study shows that PAF may be involved in the mechanism of genesis of human glomerular proteinuria.