Pre-resonance effects in deep UV Raman spectra of normal and deuterated water.

We have investigated the shape of the OH/OD stretching Raman band of water as a function of the excitation wavelength in the deep UV region (200-266 nm). By analyzing the spectral profiles, we highlighted selective pre-resonance effects in the high wavenumber component of the OH/OD stretching band, associated to distorted H-bonded water configurations. A van't Hoff treatment of the temperature-dependent Raman spectra provides an estimate of the thermal energy associated to the change from ordered (ice-like) to disordered configurations that agrees with values obtained by related methods based on a two-state model of water. These results open the possibility of exploiting the observed pre-resonance deep-UV signal enhancement to investigate H-bonding properties in aqueous media.

Electron-phonon coupling and vibrational properties of size-selected linear carbon chains by resonance Raman scattering.

UV resonance Raman spectroscopy of size-selected linear sp-carbon chains unveils vibrational overtones and combinations up to the fifth order. Thanks to the tunability of the synchrotron source, we excited each H-terminated polyyne (HCnH with n = 8,10,12) to the maxima of its vibronic absorption spectrum allowing us to precisely determine the electronic and vibrational structure of the ground and excited states for the main observed vibrational mode. Selected transitions are shown to enhance specific overtone orders in the Raman spectrum in a specific way that can be explained by a simple analytical model based on Albrecht's theory of resonance Raman scattering. The determined Huang-Rhys factors indicate a strong and size-dependent electron-phonon coupling increasing with the sp-carbon chain length.

Vibrational properties of graphdiynes as 2D carbon materials beyond graphene.

Two-dimensional (2D) hybrid sp-sp2 carbon systems are an appealing subject for science and technology. For these materials, topology and structure significantly affect electronic and vibrational properties. We investigate here by periodic density-functional theory (DFT) calculations the Raman and IR spectra of 2D carbon crystals belonging to the family of graphdiynes (GDYs) and having different structures and topologies. By joining DFT calculations with symmetry analysis, we assign the IR and Raman modes in the spectra of all the investigated systems. On this basis, we discuss how the modulation of the Raman and IR active bands depends on the different interactions between sp and sp2 domains. The symmetry-based classification allows identifying the marker bands sensitive to the different peculiar topologies. These results show the effectiveness of vibrational spectroscopy for the characterization of new nanostructures, deepening the knowledge of the subtle interactions that take place in these 2D materials.

Structure modulated charge transfer in carbon atomic wires.

sp-Hybridized carbon atomic wires are appealing systems with large property tunability. In particular, their electronic properties are intimately related to length, structure, and type of functional end-groups as well as to other effects such as the intermolecular charge transfer with metal nanoparticles. Here, by a combined Raman, Surface Enhanced Raman Scattering (SERS) investigation and first principles calculations of different N,N-dimethylanilino-terminated polyynes, we suggest that, upon charge transfer interaction with silver nanoparticles, the function of sp-carbon atomic wire can change from electron donor to electron acceptor by increasing the wire length. In addition, the insertion into the wire of a strong electrophilic group (1,1,4,4-tetracyanobuta-1,3-diene-2,3-diyl) changes the electron-accepting molecular regions involved in this intermolecular charge transfer. Our results indicate that carbon atomic wires could display a tunable charge transfer between the sp-wire and the metal, and hold promise as active materials in organic optoelectronics and photovoltaics.

Carbon-atom wires: 1-D systems with tunable properties.

This review provides a discussion of the current state of research on linear carbon structures and related materials based on sp-hybridization of carbon atoms (polyynes and cumulenes). We show that such systems have widely tunable properties and thus represent an intriguing and mostly unexplored field for both fundamental and applied sciences. We discuss the rich interplay between the structural, vibrational, and electronic properties focusing on recent advances and the future perspectives of carbon-atom wires and novel hybrid sp-sp(2)-carbon architectures.

Sorafenib in patients with Child-Pugh class A and B advanced hepatocellular carcinoma: a prospective feasibility analysis.

BACKGROUND: Sorafenib has shown survival benefits in patients with advanced hepatocellular carcinoma (HCC) and Child-Pugh (CP) class A liver function. There are few prospective data on sorafenib in patients with HCC and CP class B. PATIENTS AND METHODS: A consecutive prospective series of 300 patients with CP class A or B HCC were enrolled in a dual-phase trial to determine survival and safety data according to liver function (class A or B) in patients receiving oral sorafenib 800 mg daily. [Results of this study were presented in part at the ASCO 2012 Gastrointestinal Cancers Symposium, 19-21 January 2012. J Clin Oncol 2012; 30 (Suppl 4): abstract 306.] RESULTS: Overall progression-free survival (PFS), time to progression (TTP) and overall survival (OS) were 3.9, 4.1 and 9.1 months, respectively. For patients with CP class A versus B status, PFS was 4.3 versus 2.1 months, TTP was 4.2 versus 3.8 months and OS was 10.0 versus 3. 8 months. Extrahepatic spread was associated with worse outcomes but taken together with CP class, liver function played a greater role in reducing survival. Adverse events for the two CP groups were similar. CONCLUSION: Although patients with HCC and CP class B liver function have poorer outcomes than those with CP class A function, data suggest that patients with CP class B liver function can tolerate treatment and may still benefit from sorafenib.

Complete response in 5 out of 38 patients with advanced hepatocellular carcinoma treated with stem cell differentiation stage factors: case reports from a single centre.

Hepatocellular carcinoma (HCC) represents the third cause of cancer-related death. Because HCC is multi-centric with time, excluding the few transplanted patients, sooner or later it becomes untreatable with loco-regional therapies and, until some years ago, it was not responsive to systemic therapies. In 2005 a randomized trial indicated the efficacy of a product containing stem cell differentiation stage factors (SCDSF) taken from zebra fish embryos during the stage in which the totipotent stem cells are differentiating into the pluripotent adult stem cells. In such a trial the patients, with "intermediate" and "advanced" HCC according to BCLC/AASLD guidelines, presented benefit in terms of performance status (PS) and objective tumoral response, with some cases (2.4%) of complete response (CR). The aim of this cohort study is to report the experience of a tertiary referral center on the evidence of cases of CR in patients with "advanced" stage HCC treated with SCDSF as supportive care. CR was regarded as sustained disappearance of the neoplastic areas or blood supply therein, accompanied by normalization of AFP levels. Out of 49 patients consecutively recruited and retrospectively evaluated, 38 had "advanced" stage and 11 "terminal" stage. In 5 patients with "advanced" stage a sustained CR was reported (13.1%). Improvement on PS was obtained in 17 patients (34.6%). No side effects occurred. SCDSF treatment confirmed its efficacy in patients with "advanced" HCC, in terms of PS and tumoral response.

Raman scattering of molecular graphenes.

A simplified theoretical approach for modeling the off-resonance Raman scattering of molecular models of confined graphene (polycyclic aromatic hydrocarbons, PAHs) is presented and compared with the results from density functional theory calculations. This theoretical analysis not only allows for a quick estimate of the Raman scattering activity, but also correlates the Raman response to simple quantities directly linked to the molecular electronic structure. Owing to its simplicity and computational convenience the model can be applied to extended graphitic systems. The results of the Hückel calculations of the off-resonance Raman bond polarizability parameters of nanometer sized armchair and zizgag graphene flakes are shown.

[Computer terminals. Evaluation of utilization time]. / Valutazione dei tempi di utilizzo del videoterminale.

The aim of the present study was to compare the duration of computer use assessed through a software package and through self-report by questionnaire. Applied in a large Public Administration the software package led altogether to a remarkable reduction in the number of workers reaching the duration of use which requires medical examination. Nevertheless, it highlighted that self-reporting of a considerable number of workers had underestimated the computer use. The consistency with Italian laws is also discussed.

Comparison of simple tests for the non-invasive diagnosis of clinically silent cirrhosis in chronic hepatitis C.

BACKGROUND: Biopsy is the gold standard for assessing cirrhosis in patients with chronic hepatitis C virus infection, but it is expensive and at risk of complications. Alternative non-invasive methods have been developed but their usefulness remains uncertain. AIM: To compare the accuracy of five non-invasive scores in detecting cirrhosis. METHODS: We reviewed the charts and liver biopsies of 228 consecutive, treatment-naïve, hepatitis C virus-positive patients, 13.2% of whom with histological diagnosis of cirrhosis. The five alternative scores were age-platelet index, cirrhosis discriminant score, aspartate transaminases to platelet ratio index, Pohl's index, and aspartate transaminases/alanine transaminases ratio. RESULTS: The specificities of the scores were good (87-100%), but not so their sensitivities (17-67%). Accordingly positive likelihood ratios were generally good but negative likelihood ratios were suboptimal. Combinations of the scores independently related to cirrhosis only slightly change this diagnostic accuracy. Using double cut-offs to exclude/diagnoses cirrhosis, cirrhosis discriminant score classified 21% of patients without misdiagnoses and aspartate transaminases to platelet ratio index classified 85% of case with 9% of misdiagnoses. CONCLUSIONS: The five scores showed variable sensitivities and specificities in detecting liver cirrhosis, both individually and in combination. The use of double cut-off points may make the cirrhosis discriminant score and aspartate transaminases to platelet ratio index useful to reduce the number of patients submitted to liver biopsy.

[Hand-arm vibration syndrome and upper limb disorders associated with forestry work]. / Sindrome da vibrazioni mano-braccio e patologie degli arti superiori correlate con il lavoro forestale.

BACKGROUND: Occupational exposure to hand-transmitted vibration in forestry workers is associated with an increased risk for vascular, neurological and musculo-skeletal disorders of the upper limbs. OBJECTIVES: To carry out a cross-sectional study of the hand-arm vibration syndrome and soft-tissue disorders of the upper limb in a group of forestry workers employed in the Forestry Service of the Province of Trento (Italy). In the forestry worker group, usage of anti-vibration chain-saws was intermittent over a typical work year (16 weeks/yr, on average). METHODS: To investigate vascular, neurological and musculo-skeletal disorders of the upper limbs, the forestry workers (n=159) and a control group of manual workers, unexposed to hand-transmitted vibration, employed in the same Forestry Service (n=146) underwent a structured medical interview and a complete physical examination. The clinical diagnoses of vibration-induced white finger (VWF) and carpal tunnel syndrome were made according to internationally recognised consensus criteria. Occupational exposure to hand-transmitted vibration was assessed according to the recommendations of the International Standard ISO 5349-1 (2001). RESULTS: The forestry workers showed an increased prevalence of peripheral sensory-neural disturbances (33.3%), musculo-skeletal disorders of the upper limbs (37.7%), and carpal tunnel syndrome (21.4%) compared to those observed in the control group. There was no significant difference in the prevalence ofRaynaud' sphenomenon between the forestry workers (6.3%) and the controls (4.1%). After adjustment for confounding factors (age, body mass index, tobacco and alcohol consumption), a significant association was observed between peripheral neuropathies (peripheral sensory-neural disorders, carpal tunnel syndrome) and several indices of vibration exposure such as 8-hr energy-equivalent frequency-weighted acceleration [A(8) in m/s2 r.m.s.], duration of exposure (years), and lifetime vibration dose (m2/s4 hr). An excess, although not significant, risk for VWF was observed only in the forestry workers with A(8) > or = 4 m/s2 r.m.s.. In the forestry workers, there was no significant association between VWF and sensory-neural disorders, and between VWF and carpal tunnel syndrome. This finding seems to support the hypothesis that the vascular and neurological components of the hand-arm vibration syndrome develop independently of each other. Within the forestry worker group, the variable "years of tool usage" showed the strongest association with peripheral sensory-neural symptoms, carpal tunnel syndrome, and soft-tissue disorders of the upper limbs. It is likely that in the forestry workers the variable "years of tool usage" represents an overall index of duration of exposure to several adverse ergonomic and mechanical risk factors. CONCLUSIONS: The results of this study suggest a tendency for a decrease in the occurrence of VWF among forestry workers, and this finding seems to be associated with the use of anti-vibration chain saws, the reduction of exposure duration, and the improvement of work organization. On the other hand, the forestry workers showed an increase in the occurrence of peripheral sensory neuropathies, carpal tunnel syndrome, and upper-extremity musculo-skeletal disorders. This finding seems to support the view that there is epidemiological evidence for a positive association between exposure to a combination of risk factors (segmental vibration, forcefulness, awkward posture) and the occurrence of soft-tissue disorders of the upper limb in working populations.

Essential amino acids increase the growth and alkaline phosphatase activity in osteoblasts cultured in vitro.

An inadequate protein intake seems to be involved in the pathogenesis of osteoporosis. Moreover, protein from animal sources appears to protect against hip fracture, while protein from vegetable sources, which present low levels of essential amino acids, has no effect. In this preliminary work, the growth, the alkaline phosphatase activity and the collagen synthesis were evaluated in osteoblast cultures obtained from calvaria of newborn Sprague-Dawley rats and incubated with lysine, threonine, methionine, triptophan and arginine. Our results have shown that the essential amino acids can modulate the growth and the differentiation of osteoblasts cultured in vitro, confirming the relationship between osteoporotic hip fracture and inadequate protein intake. The compounds have mainly enhanced cell growth and alkaline phosphatase activity, and, to a lower degree, collagen synthesis. In summary, the essential amino acids can stimulate bone formation and could represents useful agents for the prevention and therapy of osteoporosis.

Prostaglandin F2 alpha can modulate the growth and the differentiation of bovine corneal epithelial cells cultured in vitro.

The effects of PGF2 alpha on the growth, morphology, morphometry and keratinization pattern of bovine corneal epithelial cells cultured in vitro were studied. The cells were grown with a basal medium or, in the presence of keratocytes and/or their products, using a keratocyte-conditioning medium. Cell growth was evaluated by MTT assay. Daily treatments with exogenous PGF2 alpha at concentrations equal to or lower than 10(-6) M induced significant increases in cell proliferation when the epithelial cells were cultured on a keratocyte feeder-layer or with the conditioning medium. No variations were observed in cultures grown with the basal medium. 10(-5) M PGF2 alpha induced a decrease in cell growth under all culturing conditions. PGF2 alpha did not affect cell morphology and modified only nuclear dimensions among the cells grown under different culturing conditions. No variations of any parameters were observed between cells cultured on feeder-layer, with conditioning or basal medium and the corresponding cultures supplemented with the autacoid. Moreover, PGF2 alpha induced only the disappearance of 43 kDa keratin in cells grown on basal medium, while the keratin pattern of epithelial cells cultured on feeder-layer or with the conditioning medium was not modified by the autacoid. From these data we can suppose that a cooperation could exist between PGF2 alpha and fibroblasts and their products for the modulation of cell growth. Finally, it was observed that the autacoid had no effect on cell morphology and morphometry, except for nuclear dimensions, despite the presence of other prostaglandins, such as PGE2.

Observation of thoracic duct morphology in portal hypertension by endoscopic ultrasound.

BACKGROUND: Thoracic duct dilation has been demonstrated in portal hypertension and hepatic cirrhosis by lymphangiography and laparotomy and at autopsy. It is thought to be secondary to increased hepatic lymph flow and has been described in the absence of ascites or esophageal varices. The aim of the present study was to observe thoracic duct morphology by endoscopic ultrasound in various subsets of patients with portal hypertension and hepatic cirrhosis and also to validate existing radiologic/surgical data. METHODS: The thoracic duct of 33 patients with cirrhosis and portal hypertension was studied by endoscopic ultrasound. Patients were divided into four groups: 1, patients with ascites and esophageal varices; 2, esophageal varices without ascites; 3, without esophageal varices or ascites; 4, extrahepatic portal hypertension due to pancreatic malignancy. The thoracic duct diameter was also measured in 14 control subjects (group 5). RESULTS: When the thoracic duct diameter for the five groups was compared with analysis of variance, significance was p < 0.0001; by pairwise comparison, group 1 differed from the other four groups (p < 0.05). Thoracic duct dilation (5.61 mm) was seen in group 1 patients, whereas no dilation was present in groups 2 through 4. Additionally, thoracic duct diameter in 33 portal hypertensive and/or cirrhotic patients was significantly different from that in the 14 control subjects (p = 0. 003). CONCLUSION: The thoracic duct can be reliably identified by EUS in patients with hepatic cirrhosis and portal hypertension. Dilation of the duct is seen only in patients with hepatic cirrhosis, ascites, and esophageal varices. No thoracic duct dilation is present in extrahepatic portal hypertension. Contrary to existing radiologic/surgical data, thoracic duct dilation is not seen in all patients with hepatic cirrhosis and portal hypertension signifying advanced disease. A dilated thoracic duct by endoscopic ultrasound should be considered yet another sign of portal hypertension.

A new risk of occupational disease: allergic asthma and rhinoconjunctivitis in persons working with beneficial arthropods.

Allergic asthma and rhinoconjunctivitis have been reported in workers who are constantly in close contact with arthropods during the course of breeding and research. We investigated a group of ten people working with beneficial arthropods in a "bio-factory." The following tests were carried out: skin prick test with allergens present in the workplace, baseline pulmonary function test, aspecific bronchial provocation test with ultrasonically nebulized distilled water, and pulmonary function test after workplace exposure in two subjects. The results demonstrated a good correlation between skin prick test, previous RAST positive reactions, clinical symptoms, and exposure. Pulmonary function test after workplace exposure proved positive in one asthmatic subject and in one subject with rhinoconjunctivitis. It is concluded that the evidence supports the occupational nature of these allergic diseases and that there is a need for careful surveillance and environmental monitoring within the workplace.

Scleroderma and occupational exposure.

OBJECTIVES: A case-referent study was conducted in the province of Trento, Italy, to investigate the possible association between occupational exposure and scleroderma (systemic and localized variants). METHODS: Twenty-one cases of scleroderma were ascertained from the computerized admission files of all of the local hospitals from 1976 to 1991. For each case, two age- and gender-matched referents were selected that were discharged from the hospital on the same day as the case. The subjects were interviewed with a structured questionnaire which included items for personal, work, and medical history. Exposure to organic solvents, other selected chemicals, silica dust, and hand-arm vibration was carefully investigated. RESULTS: A significant association was found between exposure to organic solvents (aromatic hydrocarbons) and scleroderma [odds ratio (OR) 9.28, 95% confidence interval (95% CI) 1.08-243.8]. For the men, the OR for exposure to silica was 5.20 (95% CI 0.48-74.1), whereas for the women it was 2.11 (95% CI 0.20-22.0) for exposure to other selected chemicals. CONCLUSIONS: The results of this case-referent study are consistent with those of previous case reports on the important role of occupation in the etiology of scleroderma. In particular, our findings confirm that exposure to organic solvents and silica is associated with this rare connective tissue disease.

[Scleroderma and occupational factors: a case-control study and analysis of literature]. / Sclerodermia e fattori occupazionali: studio caso-controllo e analisi della letteratura.

The scientific literature concerning occupational factors associated with scleroderma consists mostly of case report type studies. We therefore undertook a case-control study in the Province of Trento using as data source the Hospital Records System. The annual rate of scleroderma incidence in the period considered (1976-1991) was 5.8 per million in females and 1.5 per million in males. A statistically significant association was observed (OR = 9.28, p = 0.039) in the population under study for occupational exposure to solvents. Also, an excess risk was observed in male subjects exposed to silica dust, even though the simultaneous exposure to other risk factors, such as hand-arm vibrations, makes it difficult to establish the specific contribution of silica dust exposure.

Detection of preclinical hepatocellular carcinoma in patients with cirrhosis.

The association between hepatocellular carcinoma (HCC) and cirrhosis provides a formidable means for prospectively studying patients who are at risk of HCC. Early diagnosis of HCC is possible not only due to knowledge of the risk factors for this tumor, but also because HCC has a very long phase of intrahepatic growth and tends to grow as a solitary mass. Early diagnosis is also possible because sensitive and relatively inexpensive diagnostic tools are available. Several prospective studies of Oriental and Western patients with cirrhosis now in progress have led to the identification of many patients with small tumors. However, in the face of this evidence that screening high-risk patients may increase the yield of subclinical small tumors, no firm conclusion has yet been reached on whether early diagnosis of HCC may also increase the number of operable patients and reduce the mortality rate for this tumor.

Hepatocellular carcinoma in Italian patients with cirrhosis.

BACKGROUND AND METHODS: Patients with cirrhosis of the liver are recognized as being at risk for hepatocellular carcinoma. The magnitude of the risk, the natural history of this disease, and the possibilities for detecting potentially curable tumors in patients in the Western world are unknown. To address these questions, we examined 447 Italian patients with well-compensated cirrhosis (which was of viral origin in 62 percent of them) from 1985 through 1990, performing serum alpha-fetoprotein assays and real-time ultrasonography every 3 to 12 months. RESULTS: Hepatocellular carcinoma was found in 30 patients (7 percent) at base line and in another 29 patients (7 percent of 417 patients free of tumor at base line) during follow-up periods averaging 33 months (range, 1 to 48). The cumulative hazard of the development of hepatocellular carcinoma during follow-up was higher among patients with persistently elevated serum alpha-fetoprotein levels (12 with tumors among 42 with such levels) than among those with fluctuating levels (11 among 82) or those with consistently normal levels (6 among 255). Only 17 patients had potentially operable tumors. The proportion of potentially operable tumors among those detected during follow-up was significantly lower than the proportion at enrollment (4 of 29 vs. 13 of 30, P = 0.027). The survival at one year of the 12 patients who underwent surgery was 67 percent, and the tumor-recurrence rate was 60 percent. Outcome was not appreciably different for the five patients who refused surgery. CONCLUSIONS: In the West, as in Asia, patients with cirrhosis of the liver are at substantial risk for hepatocellular carcinoma, with a yearly incidence rate of 3 percent. Our screening program did not appreciably increase the rate of detection of potentially curable tumors.

Hepatitis C antibody in patients with chronic liver disease and hepatocellular carcinoma.

Hepatitis C virus (HCV) is the major etiologic agent of parenterally transmitted non-A, non-B hepatitis. To determine whether there is a relationship between this virus agent and hepatocellular carcinoma (HCC), the sera of patients with HCC and chronic hepatitis were assessed using a sensitive immunoassay for HCV antibody. Anti-HCV was detected in 65% of 132 patients with HCC, without any relationship with the presence of the hepatitis B surface antigen (HBsAg). The prevalence (74%) of anti-HCV was high, as expected in patients with putative non-A, non-B cirrhosis also. The prevalence of anti-HCV was less in patients with HBsAg-positive cirrhosis (28%) and in patients with disease not related to viral hepatitis and healthy controls (8%). These data suggest, but do not prove, that HCV is an important factor associated with HCC.