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111.
This study was performed to assess the utility of anti-cyclic citrullinated peptide (anti-CCP) antibodies in distinguishing between patients with rheumatoid arthritis (RA) and patients with polyarticular involvement associated with chronic hepatitis C virus (HCV) infection. Serum anti-CCP antibodies and rheumatoid factor (RF) were evaluated in 30 patients with RA, 8 patients with chronic HCV infection and associated articular involvement and 31 patients with chronic HCV infection without any joint involvement. In addition, we retrospectively analysed sera collected at the time of first visit in 10 patients originally presenting with symmetric polyarthritis and HCV and subsequently developing well-established RA. Anti-CCP antibodies and RF were detected by commercial second-generation anti-CCP2 enzyme-linked immunosorbent assay and immunonephelometry respectively. Anti-CCP antibodies were detected in 23 of 30 (76.6%) patients with RA but not in patients with chronic HCV infection irrespective of the presence of articular involvement. Conversely, RF was detected in 27 of 30 (90%) patients with RA, 3 of 8 (37.5%) patients with HCV-related arthropathy and 3 of 31 (9.7%) patients with HCV infection without joint involvement. Finally, anti-CCP antibodies were retrospectively detected in 6 of 10 (60%) patients with RA and HCV. This indicates that anti-CCP antibodies can be useful in discriminating patients with RA from patients with HCV-associated arthropathy.  相似文献   
112.
The continuous introduction of new antineoplastic drugs and their use as complex mixture emphasize the need to carry out correct health risk assessment. The aim of this study was to evaluate genotoxic effects of antineoplastic drugs in nurses (n=25) and pharmacy technicians (n=5) employed in an oncology hospital. The nurses administered antineoplastic drugs in the day-care hospital (n=12) and in the wards (n=13), and pharmacy technicians prepared the drugs in the central pharmacy. We performed the micronucleus (MN) test with lymphocytes and exfoliated buccal cells and conducted traditional analysis of chromosomal aberrations (CA). Thirty healthy subjects were selected as controls. Monitoring of surface contamination with cyclophosphamide, 5-fluorouracil, ifosfamide, cytarabine, and gemcitabine showed the presence of detectable levels only for cyclophosphamide, 5-fluorouracil and ifosfamide. In addition, we measured the 5-fluorouracil metabolite alpha-F-betaalanine in the urine of all subjects and found significant concentrations only in 3 out of 25 nurses. The micronucleus assay with lymphocytes did not show significant differences between exposed and control groups, while the same test with exfoliated buccal cells found higher values in nurses administering antineoplastic drugs than in pharmacy employees. In the CA analysis, we detected in exposed groups a significant increase (about 2.5-fold) of structural CA, particularly breaks (up to 5.0-fold). Our results confirm the genotoxic effect of antineoplastic drugs in circulating blood lymphocytes. Moreover, in exfoliated buccal cells the data show more consistent genetic damage induced during administration of the antineoplastic drugs than during their preparation. The data also stress the use of this non-invasive sampling, to assess occupational exposure to mixture of chemicals at low doses.  相似文献   
113.
Randomly amplified polymorphic DNA analysis using primer 239 (5′ CTGAAGCGGA 3′) was performed to characterize Leuconostoc sp. strains. All the strains of Leuconostoc mesenteroides subsp. mesenteroides (with the exception of two strains), two strains formerly identified as L. gelidum, and one strain of Leuconostoc showed a common band at about 1.1 kb. This DNA fragment was cloned and sequenced in order to verify its suitability for identifying L. mesenteroides subsp. mesenteroides strains.  相似文献   
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The use of Cu(I)-catalyzed azide-alkyne 1,3-dipolar cycloaddition permitted the synthesis of a new compound that is able to inhibit the HGF-induced scattering of MDCK (epithelial cells) and in vitro tumorigenesis of H1437 (non-small-cell lung cancer) and GTL-16 (human gastric carcinoma). In agreement with biochemical and biological results, docking studies within the ATP binding site of Met suggested for the new synthesized compound a binding mode similar to that of the active compound Triflorcas previously reported.  相似文献   
116.
Plasmodium falciparum is the vector of the most prevalent and deadly form of malaria, and, among the Plasmodium species, it is the one with the highest rate of drug resistance. At the basis of a rational drug design project there is the selection and characterization of suitable target(s). Thioredoxin reductase, the first protection against reactive oxygen species in the erythrocytic phase of the parasite, is essential for its survival. Hence it represents a good target for the design of new anti-malarial active compounds. In this paper we present the first crystal structure of recombinant P. falciparum thioredoxin reductase (PfTrxR) at 2.9 Å and discuss its differences with respect to the human orthologue. The most important one resides in the dimer interface, which offers a good binding site for selective non competitive inhibitors. The striking conservation of this feature among the Plasmodium parasites, but not among other Apicomplexa parasites neither in mammals, boosts its exploitability.  相似文献   
117.
Mechanisms for the onset of diabetes and the development of diabetic complications remain under extensive investigations. One of these mechanisms is abnormal homeostasis of metals, as either deficiency or excess of metals, can contribute to certain diabetic outcomes. Therefore, this paper will report the blood levels of chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), mercury (Hg), nickel (Ni), lead (Pb), selenium (Se), and zinc (Zn) in subjects with type 1 diabetes (n?=?192, mean age 48.8 years, mean disease duration 20.6 years), type 2 diabetes (n?=?68, mean age 68.4 years, mean disease duration 10.2 years), and in control subjects (n?=?59, mean age 57.2 years), and discuss the results indicating their possible role in diabetes. The metal concentrations were measured by sector field inductively coupled plasma mass spectrometry after microwave-induced acid digestion of blood samples. The accuracy was checked using a blood-based certified reference material, and recoveries of all elements were in the range of 92–101 % of certified values. Type 1 diabetes was found to be associated with Cr (p?=?0.02), Mn (p?<?0.001), Ni (p?<?0.001), Pb (p?=?0.02), and Zn (p?<?0.001) deficiency, and type 2 diabetes with Cr (p?=?0.014), Mn (p?<?0.001), and Ni (p?<?0.001) deficiency. These deficiencies were appreciated also subdividing the understudied patients for gender and age groups. Furthermore, in type 1 diabetes, there was a positive correlation between Pb and age (p?<?0.001, ρ?=?0.400) and Pb and BMI (p?<?0.001, ρ?=?0.309), while a negative correlation between Fe and age (p?=?0.002, ρ?=??0.218). In type 2 diabetes, there was a negative correlation between Fe and age (p?=?0.017, ρ?=??0.294) and Fe and BMI (p?=?0.026, ρ?=??0.301). Thus, these elements may play a role in both forms of diabetes and combined mineral supplementations could have beneficial effects.  相似文献   
118.
The scarcity of Neandertal remains from Southern Europe hampers our understanding of Neandertal variability, and can bias interpretations about Neandertal geographic variation. To address this issue, it is often important to reassess human remains that, while discovered decades ago, remain relatively unknown to the scientific community. In this contribution, we provide a complete state‐of‐the‐art comparative morphometric analysis of Leuca I, an unworn left second upper molar (LM2) discovered in 1958 in Bambino's Cave (near Santa Maria di Leuca, Apulia, Italy) and attributed to Homo neanderthalensis. Our study includes comparisons of standard metric and nonmetric data, a 2D image analysis of the occlusal surface and measurements of both 2D and 3D enamel thickness and dental tissue proportions. Although Leuca I follows the Neandertal M2s trend in some morphometric aspects (i.e., small relative occlusal polygon area), in other cases it falls to the higher end (for 3D average enamel thickness) or even outside (for 3D‐relative enamel thickness) the Neandertal M2 variability, thus increasing the known Neandertal range of variation. Am J Phys Anthropol 152:300–305, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
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NK cells differentiate in adult mice from bone marrow hemopoietic progenitors. Cytokines, including those that signal via receptors using the common cytokine receptor gamma-chain (gamma(c)), have been implicated at various stages of NK cell development. We have previously described committed NK cell precursors (NKPs), which have the capacity to generate NK cells, but not B, T, erythroid, or myeloid cells, after in vitro culture or transfer to a fetal thymic microenvironment. NKPs express the CD122 Ag (beta chain of the receptors for IL-2/IL-15), but lack other mature NK markers, including NK1.1, CD49b (DX5), or members of the Ly49 gene family. In this report, we have analyzed the roles for gamma(c)-dependent cytokines in the generation of bone marrow NKP and in their subsequent differentiation to mature NK cells in vivo. Normal numbers of NKPs are found in gamma(c)-deficient mice, suggesting that NK cell commitment is not dependent on IL-2, IL-4, IL-7, IL-9, IL-15, or IL-21. Although IL-2, IL-4, and IL-7 have been reported to influence NK cell differentiation, we find that mice deficient in any or all of these cytokines have normal NK cell numbers, phenotype, and effector functions. In contrast, IL-15 plays a dominant role in early NK cell differentiation by maintaining normal numbers of immature and mature NK cells in the bone marrow and spleen. Surprisingly, the few residual NK cells generated in absence of IL-15 appear relatively mature, expressing a variety of Ly49 receptors and demonstrating lytic and cytokine production capacity.  相似文献   
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