[Strategies for prevention and control of healthcare related infections by Acinetobacter baumannii]. / Strategie di prevenzione e controllo delle infezioni da Acinetobacter baumannii correlate all'assistenza sanitaria.

The frequent development of acquired antibiotics resistance in bacteria represents a challenge for Public Health in terms of healthcare associated infections control. Apart from the appropriate use of drugs, in particular the choice of proper antimicrobial therapy, increasing interest is, therefore, given to the non-pharmacological prevention of these infections. Acinetobacter (A.) baumannii is a micoorganism that commonly causes infections for patients hospitalized in critical hospital wards (intensive care units, burn centers, surgery, neonatology, etc) potentially severe and difficult to treat, because A. baumannii is resistant to many or sometimes all, available antibiotics (PDR - pan drug resistant). The aim of the present paper was to review the available measures for preventing and controlling the contamination and the spread of these types of bacterial infections in health care scenarios, with particular attention to two methods that stand out for efficiency and safety: hand hygiene and environmental disinfection.

[Skin antisepsis in premature infants]. / Problemi di antisepsi nei neonati prematuri.

In some premature newborns, 7 months old and with less than 1 kg of body wheight, total parenteral nutrition is used for weeks, so that good antiseptics can cooperate to the prevention of nosocomial infections, associating the best biocide effects to the best topical tolerability. Details are reported on the biocide cutaneous properties of some chloro-derivates, as sodium hypochlorite and NaDCC, of ethyl and propyl alcohols, of chlorhexidine, of iodophors and also of triclosan and octenidine (even if these latter biocids are not normally available in Italy as cutaneous antiseptics).

[Specific antisepsis and environmental disinfection in preventing "Clostridium difficile associated diarrhea"]. / Antisepsi mirata e disinfezione ambientale per la prevenzione della "'Clostridium difficile associated diarrhea".

In the last years, Clostridium difficile acquired great interest for public health because of constant increase of Clostridium difficile associated diarrhea (CDAD), especially in nosocomial field and as a consequences of its pathogenicity and virulence. Oro-faecal transmission and great environmental persistence of Clostridium difficile indicate hand hygiene of health care workers and environmental disinfection practices as key interventions for prevention and control of nosocomial CDAD. The current indications relative to the hand hygiene suggest the use of soap and water for hand washing and, to achieve a better compliance of health care workers to this treatment, the alternative use of sodium dichloroisocyanurate or alcohol-based solution or gel waterless. Regard to environmental disinfection, to avoid high concentrations of sodium hypochlorite (in the magnitude of 5.000-6.000 ppm), necessary to reduce microbic load of dirty environment, the most appropriate treatment should consist of 2 phases: preliminary cleaning with water and detergents or polyphenol, followed by treatment with solution containing 1.000 ppm available chlorine, obtained from sodium hypochlorite or sodium dichloroisocyanurate.

[Pandemic influenza: rapid sanitary-hygienic measures for initial containment of diffusion]. / Pandemia influenzale: misure igienico-sanitarie di rapida attuazione per il contenimento iniziale della diffusione.

Viral respiratory diseases may be characterized by rapid diffusion in population, that often cause epidemic outbreaks or pandemic. Besides, typical high mutations of involved virus (almost always influenza virus) can reduce the validity of the up to date available vaccine. The achievement of new vaccines can require prolonged period. In addition, the availability and efficacy of antiviral drugs against new viruses should be evaluated before their uses. Influenza virus replication occurs in the epithelial cells of the respiratory system, and viruses, present in contaminated secretions, spread mainly by aerosols generated during sneezing, coughing, and speaking. Direct and indirect contacts with contaminated fomites play a role, in transmission of viral infection, even if they are less relevant than aerosol transmission. In the absence of ready for use vaccines and active drugs, some "non-pharmaceutical" strategies can be considered decisive factors to reduce the diffusion of pandemic influenza. Hand washing and disinfection procedures, isolation of ill persons, different indication for use of surgical masks and respiratory masks have to be carefully considered.

[Antisepsis and disinfection in emerging and re-emerging viral diseases]. / Malattie virali emergenti e riemergenti: antisepsi e disinfezione mirate per prevenirne la diffusione.

Prevention and therapy of emerging and re-emerging viral diseases may be inefficient due the inavailability of specific vaccines, active chemotherapic drugs, acceptable pesticides, and vector control measures. To reduce contact spreading of viral infections, some biocides, as chlorine compounds or phenolic compounds, associated with detergents, may assume a leading position as safe substances with antiviral properties for the environmental decontamination. Detailed instructions on their use may be introduced in future guidelines related to emerging and re-emerging viral diseases.

[SARS: diagnosis, therapy, and especially prevention]. / SARS: diagnostica, terapia e soprattutto prevenzione.

The main purpose of this review is to analyze some aspects of the severe acute respiratory syndrome, SARS, in order to obtain useful data to suggest preventive actions to reduce the spreading of the disease. Many elements have been examined to reach some conclusions and to allow an updated discussion. Surgical masks protect more the patient than the caregiver. Simple or double surgical masks may be useful, as double gloving protects the hands of the surgical personnel against percutaneous transmission of HIV eventually present in contaminated blood. The frequent substitution of the external masks with a new one will improve the filtering activity against droplets produced by cough or sneezes of the patient. The use of respiratory masks may be suggested in hospitals or in restricted ventilated areas where, even if coronavirus variant is considered an environmental contaminant more than a respiratory risk, droplets nuclei may persist in the air and add consistent dangers to the heath-care givers. Considering that large and medium droplets may infect floors and surfaces, in addition to gloves, gowns, masks and eyes protection, the available list of viral and bacterial factors implicated in SARS ethiology suggests a better hand antisepsis using frequently the alcohol based gels (containing an high percentage of emollients substances), if available. A liquid soap with triclosan can also be used, if the health-care workers compliance to hand washing increases, as expected in this explosive situation. On the basis of the results of some experimental data, the environmental disinfection may be effected with ethyl alcohol 70% in water. Disinfection of floors or larger surfaces may be obtained with chlorine compounds solutions, after an accurate pre-cleaning. When corrosion, bleaching or gas production have to be avoided, chlorine compounds may be substituted by phenolic detergent disinfectants.

Catalytic cleavage of the androgen-regulated TMPRSS2 protease results in its secretion by prostate and prostate cancer epithelia.

We identified TMPRSS2 as a gene that is down-regulated in androgen-independent prostate cancer xenograft tissue derived from a bone metastasis. Using specific monoclonal antibodies, we show that the TMPRSS2-encoded serine protease is expressed as a Mr 70,000 full-length form and a cleaved Mr 32,000 protease domain. Mutation of Ser-441 in the catalytic triad shows that the proteolytic cleavage is dependent on catalytic activity, suggesting that it occurs as a result of autocleavage. Mutational analysis reveals the cleavage site to be at Arg-255. A consequence of autocatalytic cleavage is the secretion of the protease domain into the media by TMPRSS2-expressing prostate cancer cells and into the sera of prostate tumor-bearing mice. Immunohistochemical analysis of clinical specimens demonstrates the highest expression of TMPRSS2 at the apical side of prostate and prostate cancer secretory epithelia and within the lumen of the glands. Similar luminal staining was detected in colon cancer samples. Expression was also seen in colon and pancreas, with little to no expression detected in seven additional normal tissues. These data demonstrate that TMPRSS2 is a secreted protease that is highly expressed in prostate and prostate cancer, making it a potential target for cancer therapy and diagnosis.

Anti-PSCA mAbs inhibit tumor growth and metastasis formation and prolong the survival of mice bearing human prostate cancer xenografts.

Prostate stem-cell antigen (PSCA) is a cell-surface antigen expressed in normal prostate and overexpressed in prostate cancer tissues. PSCA expression is detected in over 80% of patients with local disease, and elevated levels of PSCA are correlated with increased tumor stage, grade, and androgen independence, including high expression in bone metastases. We evaluated the therapeutic efficacy of anti-PSCA mAbs in human prostate cancer xenograft mouse models by using the androgen-dependent LAPC-9 xenograft and the androgen-independent recombinant cell line PC3-PSCA. Two different anti-PSCA mAbs, 1G8 (IgG1kappa) and 3C5 (IgG2akappa), inhibited formation of s.c. and orthotopic xenograft tumors in a dose-dependent manner. Furthermore, administration of anti-PSCA mAbs led to retardation of established orthotopic tumor growth and inhibition of metastasis to distant sites, resulting in a significant prolongation in the survival of tumor-bearing mice. These studies suggest PSCA as an attractive target for immunotherapy and demonstrate the therapeutic potential of anti-PSCA mAbs for the treatment of local and metastatic prostate cancer.

Prostate stem cell antigen (PSCA) expression increases with high gleason score, advanced stage and bone metastasis in prostate cancer.

Prostate stem cell antigen (PSCA) is a recently defined homologue of the Thy-1/Ly-6 family of glycosylphosphatidylinositol (GPI)-anchored cell surface antigens. PSCA mRNA is expressed in the basal cells of normal prostate and in more than 80% of prostate cancers. The purpose of the present study was to examine PSCA protein expression in clinical specimens of human prostate cancer. Five monoclonal antibodies were raised against a PSCA-GST fusion protein and screened for their ability to recognize PSCA on the cell surface of human prostate cancer cells. Immunohistochemical analysis of PSCA expression was performed on paraffin-embedded sections from 25 normal tissues, 112 primary prostate cancers and nine prostate cancers metastatic to bone. The level of PSCA expression in prostate tumors was quantified and compared with expression in adjacent normal glands. The antibodies detect PSCA expression on the cell surface of normal and malignant prostate cells and distinguish three extracellular epitopes on PSCA. Prostate and transitional epithelium reacted strongly with PSCA. PSCA staining was also seen in placental trophoblasts, renal collecting ducts and neuroendocrine cells in the stomach and colon. All other normal tissues tested were negative. PSCA protein expression was identified in 105/112 (94%) primary prostate tumors and 9/9 (100%) bone metastases. The level of PSCA expression increased with higher Gleason score (P=0.016), higher tumor stage (P=0.010) and progression to androgen-independence (P=0. 021). Intense, homogeneous staining was seen in all nine bone metastases. PSCA is a cell surface protein with limited expression in extraprostatic normal tissues. PSCA expression correlates with tumor stage, grade and androgen independence and may have prognostic utility. Because expression on the surface of prostate cancer cells increases with tumor progression, PSCA may be a useful molecular target in advanced prostate cancer.

The survival function of the Bcr-Abl oncogene is mediated by Bad-dependent and -independent pathways: roles for phosphatidylinositol 3-kinase and Raf.

The Bcr-Abl tyrosine kinase constitutively activates cytokine signal transduction pathways that stimulate growth and prevent apoptosis in hematopoietic cells. The antiapoptotic action of interleukin-3 (IL-3) has been linked to a signaling pathway which inactivates the proapoptotic protein Bad by phosphorylation through kinases such as Akt and Raf. Here we report also that expression of Bcr-Abl leads to phosphorylation of Bad in hematopoietic cells. Bad phosphorylation induced by Bcr-Abl is kinase dependent, requires phosphatidylinositol 3-kinase (PI3-kinase), and mitochondrial targeting of Raf, and occurs independently of Erk. The ability of Bcr-Abl to confer cytokine-independent survival to hematopoietic cells was compromised by inhibitors of PI3-kinase, as well as by a dominant negative form of Raf targeted to the mitochondria. Furthermore, when the capacity of Bcr-Abl to phosphorylate Bad was completely blocked by dominant negative Raf, a subpopulation of cells remained viable, providing evidence for Bad-independent survival pathways. This alternative survival pathway remained PI3-kinase dependent. Finally, Bcr-Abl, but not IL-3, inhibited the proapoptotic activity of overexpressed Bad. We conclude that the antiapoptotic function of Bcr-Abl is mediated through pathways involving PI3-kinase and Raf and that survival can occur in the absence of Bad phosphorylation.

STEAP: a prostate-specific cell-surface antigen highly expressed in human prostate tumors.

In search of novel genes expressed in metastatic prostate cancer, we subtracted cDNA isolated from benign prostatic hypertrophic tissue from cDNA isolated from a prostate cancer xenograft model that mimics advanced disease. One novel gene that is highly expressed in advanced prostate cancer encodes a 339-amino acid protein with six potential membrane-spanning regions flanked by hydrophilic amino- and carboxyl-terminal domains. This structure suggests a potential function as a channel or transporter protein. This gene, named STEAP for six-transmembrane epithelial antigen of the prostate, is expressed predominantly in human prostate tissue and is up-regulated in multiple cancer cell lines, including prostate, bladder, colon, ovarian, and Ewing sarcoma. Immunohistochemical analysis of clinical specimens demonstrates significant STEAP expression at the cell-cell junctions of the secretory epithelium of prostate and prostate cancer cells. Little to no staining was detected at the plasma membranes of normal, nonprostate human tissues, except for bladder tissue, which expressed low levels of STEAP at the cell membrane. Protein analysis located STEAP at the cell surface of prostate-cancer cell lines. Our results support STEAP as a cell-surface tumor-antigen target for prostate cancer therapy and diagnostic imaging.

Interleukin-6-induced inhibition of multiple myeloma cell apoptosis: support for the hypothesis that protection is mediated via inhibition of the JNK/SAPK pathway.

The mechanism by which interleukin-6 (IL-6) protects multiple myeloma (MM) plasma cells from apoptosis induced by anti-fas antibodies and dexamethasone was studied. Anti-apoptotic concentrations of IL-6 had no effect on cell-cycle distribution or activation of RAF-1 or ERK in dexamethasone- or anti-fas-treated 8226 and UCLA #1 MM cell lines. However, IL-6-dependent protection of viability correlated with an inhibition of dexamethasone- and anti-fas-induced activation of jun kinase (JNK) and AP-1 transactivation. To test the hypothesis that cytokine-induced protection was mediated through inhibition of JNK/c-jun, we also inhibited c-jun function in 8226 cells via introduction of a mutant dominant negative c-jun construct. Mutant c-jun-containing MM cells were also resistant to anti-fas-induced apoptosis but were significantly more sensitive to dexamethasone-induced apoptosis. These results support the notion that IL-6 protects MM cells against anti-fas through its inhibitory effects on JNK/c-jun but indicate protection against dexamethasone occurs through separate, yet unknown pathways.

A cytoplasmic inhibitor of the JNK signal transduction pathway.

The c-Jun amino-terminal kinase (JNK) is a member of the stress-activated group of mitogen-activated protein (MAP) kinases that are implicated in the control of cell growth. A murine cytoplasmic protein that binds specifically to JNK [the JNK interacting protein-1 (JIP-1)] was characterized and cloned. JIP-1 caused cytoplasmic retention of JNK and inhibition of JNK-regulated gene expression. In addition, JIP-1 suppressed the effects of the JNK signaling pathway on cellular proliferation, including transformation by the Bcr-Abl oncogene. This analysis identifies JIP-1 as a specific inhibitor of the JNK signal transduction pathway and establishes protein targeting as a mechanism that regulates signaling by stress-activated MAP kinases.

The Bcr-Abl leukemia oncogene activates Jun kinase and requires Jun for transformation.

The leukemogenic tyrosine kinase fusion protein Bcr-Abl activates a Ras-dependent pathway required for transformation. To examine subsequent signal transduction events we measured the effect of Bcr-Abl on two mitogen-activated protein kinase (MAPK) cascades--the extracellular signal-regulated kinase (ERK) pathway and the Jun N-terminal kinase (JNK) pathway. We find that Bcr-Abl primarily activates JNK in fibroblasts and hematopoietic cells. Bcr-Abl enhances JNK function as measured by transcription from Jun responsive promoters and requires Ras, MEK kinase (MAPK/ERK kinase kinase), and JNK to do so. Dominant-negative mutants of c-Jun, which inhibit the endpoint of the JNK pathway, impair Bcr-Abl transforming activity. These findings implicate the JNK pathway in transformation by a human leukemia oncogene.

Growth inhibition of a human colorectal carcinoma cell line by interleukin 1 is associated with enhanced expression of gamma-interferon receptors.

Recombinant human tumor necrosis factor and recombinant human gamma interferon (IFN-gamma) exert synergistic growth inhibitory effects in WiDR human colorectal carcinoma cells. In this cell line, tumor necrosis factor increases IFN-gamma binding. Interleukin 1 (IL-1) is a cytokine that mimics many of the biological actions of TNF. Therefore, in the present study, we investigated the effects of recombinant human IL-1 on cell growth and IFN-gamma receptor expression in WiDR cells. IL-1 slightly inhibited the growth of WiDR cells, and exerted additive growth inhibitory effects in the presence of IFN-gamma. IL-1 caused a time- and dose-dependent increase in 125I-labeled IFN-gamma binding that was maximal at 6 h, persisted for at least 24 h, and was blocked by both actinomycin D and cycloheximide. The increase in binding was associated with an increase in cell surface IFN-gamma receptor protein expression as determined by Scatchard analysis of equilibrium binding data and by immunofluorescent staining with an anti-human IFN-gamma receptor monoclonal antibody. IL-1 also produced a time- and dose-dependent increase in IFN-gamma receptor mRNA levels that was maximal at 3 h and persisted for at least 24 h. Actinomycin D, but not cycloheximide, completely blocked the IL-1-mediated increase in IFN-gamma receptor mRNA levels. However, IL-1 did not alter IFN-gamma receptor mRNA half-life. These data indicate that IL-1 and IFN-gamma exert additive growth inhibitory effects on colon cancer cell growth, and suggest that IL-1 increases IFN-gamma receptor expression in these cells by enhancing IFN-gamma mRNA levels.

Effects of chronic administration of ephedrine during very-low-calorie diets on energy expenditure, protein metabolism and hormone levels in obese subjects.

1. We investigated the effects of the chronic administration of a sympathomimetic agent on energy expenditure, protein metabolism and levels of thyroid hormones and catecholamines in 10 obese subjects after a 6-week very-low-calorie-diet programme (1965 kJ, 60 g of protein, 45 g of carbohydrates). L-(-)-Ephedrine hydrochloride (50 mg three times a day by mouth) or placebo were administered during 2-week periods (weeks 2-5 of the VLCD programme) in a randomized, double-blind, cross-over design. Five subjects began with ephedrine and five with placebo. 2. The results were analysed separately in the two groups. No difference was found between them as regards weight loss during the very-low-calorie diet and drug treatments. Conversely, ephedrine therapy induced a significantly lower daily urinary excretion of nitrogen (and, consequently, a better nitrogen balance) with respect to placebo, independently of the drug sequence. Daily urinary levels of 3-methylhistidine during ephedrine and placebo treatments were similar. The fasting resting metabolic rate (oxygen consumption, ml STP/min) fell significantly during the very-low-calorie diet in both groups, but this effect was partially and significantly prevented by administration of ephedrine. Diet therapy significantly reduced 24 h urine levels of vanillylmandelic acid and homovanillic acid, which, however, increased to pretreatment values during ephedrine treatment. No significant effects were shown on 24 h urinary concentrations of adrenaline, noradrenaline and dopamine during the very-low-calorie diet and/or ephedrine treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Upregulation of interferon-gamma binding by tumor necrosis factor and lymphotoxin: disparate potencies of the cytokines and modulation of their effects by phorbol ester.

Tumor necrosis factor (TNF) and interferon-gamma (IFN-gamma) are immune-modulating cytokines that exert synergistic cytotoxic effects in several types of tumor cells, including ASPC-1 human pancreatic carcinoma cells. Lymphotoxin (LT), is a cytokine that binds to the TNF receptor and mimicks most of the biological actions of TNF. In the present study, we examined ASPC-1 cells for cytokine-mediated modulation of TNF and IFN-gamma receptors. Treatment of ASPC-1 cells with recombinant human IFN-gamma (rhIFN-gamma) did not significantly alter 125I-rhTNF binding. In contrast, treatment with rhTNF led to a dose- and time-dependent increase in 125I-rhIFN-gamma binding and internalization. Scatchard analysis revealed that rhTNF increased the number of 125I-rhIFN-gamma binding sites from 11,000 sites/cell to 23,000 sites/cell without altering receptor affinity. Although rhLT also increased 125I-rhIFN-gamma binding, it was 100-fold less potent than rhTNF. In contrast, rhLT was only 10-fold less potent than rhTNF in displacing 125I-rhTNF from its receptor. The phorbol ester 12-O-tetradecanoyl phorbol-13-acetate (TPA) blocked the rhLT- and rhTNF-mediated increase in 125I-rhIFN-gamma binding and markedly decreased 125I-rhTNF binding. These data suggest that both TNF and LT upregulate IFN-gamma receptors in ASPC-1 cells, but that LT is much less efficient than TNF. Further, the TPA-induced attenuation of IFN-gamma receptor upregulation suggests that protein kinase C activation can regulate the TNF/LT-mediated pathways involved in IFN-gamma receptor upregulation.

Tumor necrosis factor up-regulates gamma-interferon binding in a human carcinoma cell line.

WiDR colorectal carcinoma cells are highly sensitive to the synergistic cytotoxic effects of tumor necrosis factor (TNF) and gamma-interferon (IFN-gamma). In the present study, we have investigated the effects of recombinant human (rh) TNF and IFN-gamma on the binding of both ligands in this cell line. WiDR cells exhibited high affinity binding sites for both 125I-rhTNF (Kd = 1.66 x 10(-10) M, 920 sites/cell) and 125I-rhIFN-gamma (Kd = 4.15 x 10(-10) M, 18,960 sites/cell). Preincubation of the cells with rhTNF (24 h) increased cell-associated 125I-rhIFN-gamma radioactivity by 129% when binding was carried out at 37 degrees C, as a result of an increase in both surface bound and internalized 125I-rhIFN-gamma. However, rhTNF did not alter the degradation profile of released 125I-rhIFN-gamma radioactivity. Scatchard analysis of 125I-rhIFN-gamama binding data (4 degrees C) revealed that rhTNF induced a 245% increase in 125I-rhIFN-gamma binding sites. Conversely, rhIFN-gamma caused a 68% increase in 125I-rhTNF binding sites and a 58% increase in receptor affinity. rhIFN-gamma also increased the subsequent binding of 125I-rhIFN-gamma, whereas rhTNF increased the subsequent binding of 125I-rhTNF. Furthermore, preincubation of the cells with both rhTNF and rhIFN-gamma also resulted in an increase in the binding of both ligands. Actinomycin D and cycloheximide blocked all the effects of rhTNF and rhIFN-gamma on ligand binding. However, the basal level of 125I-rhIFN-gamma binding was insensitive to either inhibitor, whereas the basal level of 125I-rhTNF binding was decreased by both inhibitors. These data indicate that in some cell types TNF and IFN-gamma may induce an increase in their own receptors (homologous up-regulation) and concomitantly increase each other's receptors (heterologous up-regulation) and that these actions are due, in part, to enhanced receptor synthesis.