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A surface analysis has been conducted on a series of electrodeposited nickel-phosphorus (Ni–P) alloys containing from 6 to 29 at.% phosphorus, using X-ray photoelectron spectroscopy (XPS) and X-ray excited Auger electron spectroscopy (XAES). No changes in core-level binding energies, Ni2p3/2 and Ni2p1/2, P2p, P2s, or X-ray excited NiLMM and PKLL Auger lines were observed regardless of phosphorus concentration. The only systematic differences observed concerned: (i) the binding energy of the Ni2p satellite peak, (ii) the fine structure of the NiLMM Auger lines, (iii) the percentage of the satellite in the total Ni2p3/2 spectrum and (iv) the valence band density of states in the Ni3d electrons region, all related to the electronic structure of the Ni–P alloys. For the first time, it has been possible to describe and rationalise the influence of (phosphorus) ligand concentration on the electronic structure of nickel-based alloys, using a screening model proposed in the literature for clarifying the role of substituents on the electronic structure of conductor compounds of nickel. As the phosphorus content increases, the number of non-bonding Ni3d electrons decreases. Thus the d-type core-hole screening is less pronounced and the binding energy of the satellite for the final state with a filled Ni4s shell increases. Copyright © 2008 John Wiley & Sons, Ltd.

Enargite surface reactivity in acidic ferric solutions simulating the acid mine drainage (AMD) environment has been investigated by X-ray photoelectron (XPS) and X-ray excited Auger electron spectroscopy (XAES) surface analysis. Natural enargite samples from a Peruvian mine with close to the nominal composition Cu3AsS4 have been analysed after cleavage and a 24 h exposure to 0.025 mol/l ferric acidic solutions. The results, based on the calculated modified Auger parameter α′, show that the chemical state of copper and arsenic in enargite does not change during immersion in acidic, oxidising solutions. The sulfur S 2p spectrum of enargite is characterized by two components, one at 162.0 ± 0.2 eV and the other at 163.5 ± 0.2 eV. The lower binding energy component (162.0 eV) is attributed to the sulfur atoms in enargite. Immersion does not change the chemical state of this compound. XPS/ARXPS measurements show the intensity of the higher binding energy component (163.5 ± 0.2 eV), located at the outermost surface of the reacted enargite, to increase after immersion in solutions. The chemical state plot suggests that this sulfur compound might be associated with the formation of a copper-deficient enargite surface layer and not with elemental sulfur. Based also on the quantitative XPS determinations, the surface of the reacted enargite can be described as a layered structure: a thin copper-deficient enargite layer (up to 0.7 nm) is formed on a slightly sulfur-enriched enargite surface, the arsenic content remaining constant. Copyright © 2007 John Wiley & Sons, Ltd.

The distal lateral arm flap (DLAF) was used to reconstruct six extensive defects of the digits: 2 degloving injuries of the thumb and 4 major skin losses of the fingers. Two adjacent fingers were involved in 1 patient. Flap size ranged from 3 × 7 cm to 9 × 14 cm. Four flaps were reinnervated using the posterior cutaneous nerve of the forearm. All flaps survived, though 1 showed marginal necrosis. Average follow-up was 53.4 months. Thumb opposition scored 5 according to Kapandji; finger ROM averaged 50.75%; pinch strength 72.5%. Protective sensation with touch localization was restored. Patient satisfaction for resurfaced digits averaged 8.9 on a 10-points visual analogic scale. All donor sites resulted in a painless scar with good patient satisfaction. The DLAF offers a thin, pliable skin ideal for digit reconstruction, with low rate of donor site morbidity and can be considered when toe-to-hand flap transfer is not advisable or refused by the patient. © 2007 Wiley-Liss, Inc. Microsurgery, 2007.

Objective To define the prevalence of major cardiac defects according to nuchal translucency (NT) thickness at the 11 to 13+ 6-week scan in fetuses with normal karyotype. Methods Specialist fetal echocardiography was carried in 6921 fetuses with normal or presumed normal karyotype at a median gestation of 20 (range 12–35) weeks. The indications for fetal echocardiography were increased NT thickness (n = 3444), detailed second-trimester scan either for assessment of risk of chromosomal abnormalities (n = 2980) or previous or family history of fetal defects (n = 497). The cardiac defects were grouped into six functional categories: septal defect, left inflow obstruction, right inflow obstruction, left outflow obstruction, right outflow obstruction and other.

In order to find the conditions under which Tc-99m-methylenediphosphonate (Tc-99m-MDP) and Tc-99m(V)-dimercaptosuccinate (Tc-99m(V)-DMSA) may become tumour-seeking agents, leaving healthy organs free from the radionuclide uptake, the solution chemistry of these radiopharmaceuticals was studied by paper chromatography and paper electrophoresis in distilled water, in physiological saline, in NAHCO3, and ascorbic acid solutions. Both radiopharmaceuticals are anionic in the radiopharmaceutical solution but get easily hydrolysed to form cationic Tc-99m species which concentrates in healthy bone and in some bone metastases. Tc-99m (V)-DMSA being more stable remains long in the blood pool giving undesirable presence of the radionuclide in lung, heart and kidneys, in addition to its reduced uptake in bone metastases and in some primaries. We are trying to eliminate these drawbacks of healthy organ uptake of Tc-99-m(V)-DMSA not only to get a clean scintigraphic image of the tumour with this radiopharmaceutical but to extend its formulation, thus obtained, to prepare radiopharmaceutical with Re-188, which is the higher homologue of Tc-99m, for systemic therapy of cancer. Essentially similar solution chemistry of both radiopharmaceuticals suggests that like Tc-99m-MDP, technetium-99m-dimercaptosuccinate is also a complex of tetravalent Tc-99m and not of pentavalent Tc-99m as so far supposed to be.

X-ray photoelectron spectroscopy (XPS) has been used to determine the species present in urban particulate matter collected in the city of Cagliari (Sardinia, Italy) and in an industrial area near to Cagliari. Samples were collected on both cellulose and glass fiber filters. Elemental identification, chemical state and quantitative analyses of the examined samples indicated the presence of Na3AlF6, SiO2 and Al2O3 in the ratio 2:2:5, carbon and oxygen being the major components. The results obtained on NIST SRM 1648 urban particulate matter, before and after grinding, are also presented.

The essential oils from nine wild populations of the Sardinian Thymus herba-barona Loisel (Labiatae) were chemically characterized to identify the different chemotypes. GC and GC–MS analysis showed that in Sardinia only two chemotypes (thymol and carvacrol) are present. The carvacrol chemotype is predominant and this compound was found in high concentration (50.7–79.4%) in seven of the nine populations studied. The thymol chemotype was found in only two populations (34.2–56.2%). Analyses also showed that the other main components of the oils of T. herba-barona, were 3-heptanone (1.4–5.6%), 3-octanone (1.4–5.5%) and borneol (2.5–8.3%). p-Cymene is present at 1.2–5.6% but is not present in plants from the Tonara medium station, where O-cymene (1.9%) is present instead. Copyright © 2002 John Wiley & Sons, Ltd.

Plasticized poly(vinyl chloride) (PVC) used for biomedical disposable devices was studied in the non-sterilized state after different exposure times to soft x-ray irradiation in a commercial photoelectron spectrometer (Al Kα, 15 kV/300 W; Mg Kα, 12 kV/240 W) by XPS surface analysis. The detailed spectra of C 1s, Cl 2p and O 1s have been recorded and processed. Irradiation with soft x-rays induces a clear decrease of the total Cl 2p intensity, an increase of total C 1s intensity and a doubling of the O 1s intensity after 45 min of irradiation with Al Kα (300 W). Irradiation with Mg Kα (240 W) is slightly less damaging. These results can be interpreted with the classical PVC degradation model, e.g. bond cleavage with the formation of HCl gas, although the Cl 2p high-resolution spectra reveal the formation of an additional side-product, probably CaCl2. For further studies of plasticized PVC using XPS surface analysis it can be concluded that a complete analysis of a polymer sample should not take >10 min of x-ray exposure in order to avoid notable polymer degradation. Copyright © 2003 John Wiley & Sons, Ltd.

Extruded parts of non-sterilized and β-irradiated (25 and 50 kGy) plasticized poly(vinyl chloride) (PVC) used for disposable medical devices have been studied to investigate the effect of sterilization on surface chemical composition. The polymer surfaces were analysed using angle-resolved x-ray photoelectron spectroscopy. The inner surface of the blood tubing lines showed a fairly smooth surface both before and after sterilization, so a laterally homogeneous surface can be assumed for XPS analysis. The XPS survey spectra exhibited no signals besides carbon, chlorine, oxygen and calcium. Detailed analysis of the regions showed the C 1s, Cl 2p and O Is signals to be multi-component, presenting signals of the PVC, the plasticizer and the other additives. Binding energies remained constant irrespective of β-radiation dosage, but the amount of chlorine component at 198.4 ± 0.1 eV (associated with modified PVC) decreased with sterilization dosage. Angle-resolved XPS revealed that this component is located at the outermost surface of the polymer. It can be hypothesized that the production processes themselves (extrusion and/or injection molded) already induce modifications of the polymer surface and also lead to surface segregation of the plasticizer. During the subsequent thermal sterilization of the polymer dehydrochlorination continues but, because of the very short time required by the β-irradiation technology to sterilize devices, the atmospheric oxygen is unable to diffuse into the irradiated material, thus inhibiting further side-degradation of the materials, such as thermo-oxidative degradation.

In advanced cancer patients, the oxidative stress could take place either at the onset of disease or as a function of disease progression. To test this hypothesis, the following parameters were investigated: the erythrocyte activity of the enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx), the serum activity of glutathione reductase (GR) and the serum total antioxidant status (TAS). The total antioxidant capacity of plasma LMWA was evaluated by the cyclic voltammetry methodology. We further determined the serum levels of proinflammatory cytokines (IL-6 and TNFalpha), IL-2, leptin and C-reactive protein (CRP). All of these parameters have been correlated with the most important clinical indices of patients such as Stage of disease, ECOG PS and clinical response. Eighty-two advanced stage cancer patients and 36 healthy individuals used as controls were included in the study. Our findings show that SOD activity was significantly higher in cancer patients than in controls and GPx activity was significantly lower in cancer patients than in controls. Serum values of IL-6, TNFalpha and CRP were significantly higher in patients than in controls. Serum leptin values of cancer patients were significantly lower than controls. SOD activity increased significantly from Stage II/ECOG 0-1 to Stage IV/ECOG 0-1, whereas it decreased significantly in Stage IV/ECOG 3. GPx activity decreased significantly in Stage IV/ECOG 2-3. An inverse correlation between ECOG PS and serum leptin levels was found. Serum levels of IL-2 decreased from Stage II/ECOG 0-1 to Stage IV/ECOG 2-3. A direct correlation between Stage/ECOG PS and serum levels of both IL-6 and CRP was observed. Cisplatin administration induced a significant increase of GPx after 24 hr. In conclusion, this is the first study that shows that several "biological" parameters of cancer patients such as antioxidant enzyme activity, cytokines, leptin and CRP strictly correlate with the most important clinical parameters of disease such as Stage and ECOG PS.

The surface chemical state and composition of natural and synthetic enargite samples were characterized with X-ray photoelectron spectroscopy (XPS). Freshly cleaved, powdered and ‘as received’ samples were analysed at liquid nitrogen temperature. For the natural ‘as received’ samples as well as for the natural and synthetic powdered samples the binding energies of Cu 2p3/2, As 3d5/2 and S 2p are consistently found at 932.5 ± 0.2, 43.9 ± 0.2 and 162.2 ± 0.2 eV, respectively. A second component of S 2p at 163.9 ± 0.2 eV is present and may be assigned to elemental sulphur. Freshly cleaved enargite samples showed binding energies of 43.2 and 161.3 eV, respectively, for As 3d5/2 and S 2p3/2. At the surface of crystals ‘as received’, an additional signal at ∽169 eV, referable to sulphate sulphur, is also present, as well as additional signals for Cu 2p3/2 (∽934 eV), and As 3d5/2 (∽45.5 eV). The thickness and the composition of this outer oxidized layer together with the composition of the interface beneath the film are calculated on the basis of a model developed for this purpose, taking into account the attenuation of the photoelectrons due to the contamination and the oxidized layer. An oxidized film of ∽0.5 nm is present at the surface of the ‘as received’ crystals whose composition was found to be ∽45% copper, 24% arsenic and 31% sulphur; hence, the oxidized layer appears to be enriched in arsenic compared with the bulk composition. The composition of the material beneath the oxidized layer was found to be enriched in copper and depleted in sulphur with respect to the bulk analysis. Any further study of the interaction of natural enargite samples with the environment has to take into account the existence of this thin outer layer. Copyright © 2001 John Wiley & Sons, Ltd.

PROBLEM Tumor necrosis factor-alpha (TNFalpha) is produced by the endometrium, and it has been shown that this cytokine has cyclic variations through the menstrual cycle. METHOD OF STUDY In this study we assessed TNFalpha, estradiol and progesterone levels in the endometrium and serum of 21 patients with recent abnormal uterine bleeding (AUB). Eleven women showed histological diagnosis of endometrial hyperplasia, and ten women showed normal endometrium. RESULTS The TNFalpha value in the serum of patients with hyperplasia and in normal endometrium did not show significant differences (64.8 +/- 21.4 vs 77.6 +/- 14.8 pg). The amounts of TNFalpha released by hyperplastic endometrial tissue were significantly higher than in control patients (258.8 +/- 78.0 vs 140.6 +/- 79.8 pg/g; P < 0.001). Immunohistochemistry of hyperplastic endometria showed a stronger staining than normal ones. Serum E2 levels in patients with hyperplastic endometrium were 49.5 +/- 31.6 ng/mL, and in controls were 107.3 +/- 66.0 ng/mL. The levels of estradiol released by hyperplastic endometria were significantly lower than in normal endometria (152.7 +/- 60.0 vs 279.9 +/- 178.7 ng/g; P < 0.003). CONCLUSIONS Hyperplastic endometria produce higher amounts of TNFalpha with respect to controls. These findings may explain the frequent bleeding observed in the patients with endometrial hyperplasia, since TNFalpha promotes apoptosis and endometrial shedding.

Background: The efficacy of omeprazole and amoxycillin dual therapy to treat Helicobacter pylori infection has been inconsistent, suggesting the presence of host or bacterial factors influencing treatment success. The aim of this study was to assess the role of pre-treatment amoxycillin resistance in the efficacy of omeprazole and amoxycillin dual therapy. Methods: We studied 43 consecutive dyspeptic patients with H. pylori infection. Pre-treatment H. pylori infection was established by the combination of positive rapid urease test, culture and histology. Amoxycillin susceptibility testing was performed by an Epsilometer test (E-test) method and amoxycillin resistance was defined as minimum inhibitory concentration greater than 8 μg/mL. Patients received 20 mg omeprazole twice daily for 28 days and amoxycillin 1000 mg twice daily for 2 weeks. Adverse effects were documented using a questionnaire. H. pylori status was reassessed 6–8 weeks after the end of treatment by rapid urease testing and histological examination of gastric biopsies. Results: Forty-two dyspeptic patients completed the study, and one patient dropped out. H. pylori infection was cured in 23 of 42 patients (55%). The cure rate was higher in patients harbouring amoxycillin-sensitive organisms than in those with resistant strains: 66% (19/29) vs. 31% (4/13), respectively (P = 0.049). No significant differences in cure rates were evident in relation to age, sex, smoking habits or compliance. Conclusions: The effectiveness of amoxycillin–omeprazole dual therapy was greatly reduced in the presence of pre-treatment amoxycillin-resistant H. pylori. The success rate in patients with amoxycillin-sensitive H. pylori was only 66%, suggesting the presence of additional factors affecting the efficacy of this therapy.

Objective To evaluate the influence of maternal insulin dependent diabetes mellitus (IDDM) on maternal serum free β-hCG, PAPP-A and fetal nuchal translucency (NT), thickness at 11 to 13+6 weeks of gestation in a large cohort of women screened prospectively for chromosomal anomalies. Methods Information on maternal IDDM status, maternal serum biochemical marker levels and fetal NT were collected from the prenatal screening computer records in two first-trimester screening centres. In total the control group included 33 301 pregnancies of which 16 366 had NT and maternal serum biochemistry results and 16 305 with NT only. The IDDM group included 195 pregnancies of which 79 had NT and maternal serum biochemistry results and 127 with NT only. The median maternal weight corrected free β-hCG and PAPP-A, expressed as multiple of the median (MoM), and fetal NT, expressed as delta values, in the IDDM and non-IDDM groups were compared. Results There were no significant differences between the IDDM and non-IDDM groups in median maternal weight corrected free β-hCG (IDDM 0.87 MoM, 95% Confidence Interval 0.75 to 1.16 MoM, non-IDDM 1.00 MoM), median maternal weight corrected PAPP-A (IDDM 1.02 MoM, 95% Confidence Interval 0.83 to 1.05 MoM, non-IDDM 1.01 MoM), or mean delta NT (IDDM 0.0358 mm, non-IDDM 0.0002 mm). Conclusions In pregnancies with maternal IDDM, first-trimester screening for chromosomal defects does not require adjustments for the measured fetal NT. However, more data are required before the possible reduction in maternal serum free β-hCG and the reduction of PAPP-A suggested by the published world series can be considered sufficiently important to take into account in the calculation of risks for chromosomal defects. Copyright © 2005 John Wiley & Sons, Ltd.

The neurotrophin (NT) family includes nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3) and NT-4/5. Keratinocytes synthesize and release all NTs. Keratinocytes express the low-affinity p75 receptor which binds all NTs, the high-affinity NGF receptor trkA and the NT-3 receptor trkC. By contrast, keratinocytes express only a truncated form of trkB, the BDNF high-affinity receptor. NT-3 stimulates keratinocyte proliferation. NTs other than NGF fail to protect keratinocytes from UVB-induced apoptosis. While NGF decreases upon UVB irradiation, NT-3 and NT-4 are upregulated. UVA dose dependently increases NT-3 levels. NT-3 and NGF stimulate each other release. Both fibroblasts and myofibroblasts synthesize and release all NTs, as well as their trk receptors except for trkC. p75 is more expressed in myofibroblast than in fibroblasts. NGF reduces secretion of collagen I in myofibroblasts. Myofibroblasts secrete more collagen I than fibroblasts. NGF reduces production of metalloproteinase 2 (MMP2) in myofibroblasts. Melanocytes synthesize and release all NTs. UVB irradiation upregulates the release of NT-3, while it downregulates the release of NT-4. Melanocytes express p75, which is downregulated by UVB. Melanocytes also express trkA and the extracellular domain of trkB. Taken together, these data indicate that a complex NT network exists in human skin with potential functions, partly to be determined.

Objectives: Previously we showed that sonovaginography is an accurate ultrasonographic tool in the assessment of rectovaginal endometriosis. The aim of this study was to compare the diagnostic accuracy of sonovaginography and NMR in the diagnosis of rectovaginal endometriosis. Methods: This was a longitudinal prospective study in which 28 women with rectovaginal endometriosis suspected from the medical history and/or pelvic examination were enrolled. The study group underwent transvaginal ultrasonography and sonovaginography was performed in the same session as follows: an assistant inserted a Foley catheter into the vagina and an ultrasound probe covered with a specific balloon to swell the vagina. The balloon was filled with water (mean 40 mL) and soon after 60–180 mL saline solution was inserted through the Foley catheter to fill the vagina in order to create an acoustic window through the vagina to detect rectovaginal lesions. Within a mean of 30 days after the examination patients were scheduled for pelvic NMR. Once all the diagnostic tests had been performed, patients underwent laparoscopic surgery to enucleate the endometriotic lesion, which was sent for pathological examination. Results: Twenty-three (82.1%) patients had rectovaginal endometriotic lesions. The sensitivity of sonovaginography was 91.7%, specificity 75%, PPV 95.6% and NPV 60%; the area under the receiver-operating characteristic (ROC) curve was 0.87. In comparison, NMR had a sensitivity of 73.9%, specificity 60%, PPV 89.5% and NPV 33.3%, with an area under the ROC curve of 0.67. The procedure was well tolerated with a median visual analogue scale score of 2 (range, 0–8). Conclusions: Sonovaginography is a well tolerated procedure, with higher accuracy than NMR in the detection of rectovaginal endometriosis.