817 resultados para disordered solid
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OBJECTIVE To evaluate the frequency and clinical features of endemic and other opportunistic infections in liver or kidney transplant recipients in four transplant centres in different geographical areas of Brazil. METHODS Retrospective analysis of medical and laboratory records of four transplant centres on endemic and other opportunistic infections in liver or kidney transplant recipients. Analyses were performed with spss statistical software. RESULTS From 2001 to 2006, 1046 kidney and 708 liver transplants were registered in all centres. The average age was 42 years. Among 82 (4.7%) cases with infections, the most frequent was tuberculosis (2.0%), followed by systemic protozoal infections (0.7%), toxoplasmosis (0.4%) and visceral leishmaniasis (0.3%). Systemic fungal infections occurred in 0.6%, of which 0.4% were cryptococcosis and 0.2% were histoplasmosis. Dengue was the only systemic viral infection and was registered in two cases (0.1%), of which one was classified as the classic form and the other as dengue haemorrhagic fever. Nocardiosis was described in one case (0.05%). The infectious agents most frequently associated with diarrhoea were Blastocystis sp., Schistosoma mansoni and Strongyloides stercoralis. CONCLUSIONS Opportunistic Infections in transplant patients have a wide spectrum and may vary from asymptomatic to severe infections with high mortality. A better understanding of the epidemiology of endemic pathogens and clinical manifestations can contribute to the establishment of an early diagnosis as well as correct treatment aimed at decreasing morbidity and mortality.
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Background. Solid pseudopapillary neoplasm of the pancreas is a distinctive pancreatic neoplasm with low metastatic potential. This study examines clinical differences and prognosis between male and female Patients. Methods. The medical records of 34 consecutive patients with pancreatic solid pseudopapillaly neoplasms between 1990 and 2006 were reviewed. Whenever feasible, organ-preserving operation was performed. Statistical analysis was performed using chi-square and Student t test. Results. There were 27 women (79%) and seven men (21%) with median age of 23 years. Mean diameter of the tumor was 7 cm. Tumor size tended to be smaller in patients treated in more recent years. Conservative surgery was possible in I I patients including spleen-preserving distal pancreatectomy in 3, central pancreatectomy in 5, and enucleation in 3 patients. Median hospital stay was 11 days, morbidity rate was 62%, including 17 patients with grade A pancreatic fistula, and there was no operative mortality. Mean follow-up time was 84 months. Tumor recurred in 2 patients (6%). Overall late morbidity rate was 12%. At the time of diagnosis, age was ((x) over bar +/- SD) higher among male patients (25 +/- 2 years vs 37 +/- 7 years, P < .05) with no difference in tumor size. The neoplasms were more aggressive in male Patients; therefore, conservative surgery was less likely. There was no correlation between tumor aggressiveness and age of the patient or size of tumor. Conclusion. This is the first single center study to demonstrate that solid pseudopapillary neoplasms in male patients have distinct Patterns Of onset and aggressiveness when compared with female patients. Although valid prognostic criteria are still lacking, it appears that male patients may be best treated by more radical operation and should be observed more closely during follow-up.
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Decisions for intensive care unit (ICU) admissions in patients with advanced cancer are complex, and the knowledge of survival rates and prognostic factors are essential to these decisions. Ours objectives were to describe the short- and long-term survival of patients with metastatic solid cancer admitted to an ICU due to emergencies and to study the prognostic factors presented at ICU admission that could be associated with hospital mortality. We retrospectively analysed the charts of all patients with metastatic solid cancer admitted over a 1-year period. This gave a study sample of 83 patients. The ICU, hospital, 1-year and 2-year survival rates were 55.4%, 28.9%, 12.0% and 2.4% respectively. Thrombocytopenia (odds ratio 26.2; P = 0.006) and simplified acute physiology score (SAPS II) (odds ratio 1.09; P = 0.026) were independent factors associated with higher hospital mortality. In conclusion, the survival rates of patients with metastatic solid cancer admitted to the ICU due to emergencies were low, but of the same magnitude as other groups of cancer patients admitted to the ICU. The SAPS II score and thrombocytopenia on admission were associated with higher hospital mortality. The characteristics of the metastatic disease, such as number of organs with metastasis and central nervous system metastasis were not associated with the hospital mortality.
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Autopsy is a valuable tool in evaluating diagnostic accuracy. Solid malignancies may have a protracted presentation, and diagnosis frequently requires imaging and deep-sited biopsies; clinical and postmortem diagnosis discrepancies may occur in a high rate in these diseases. Here, we analyzed the occurrence of clinico-pathological discrepancies in the diagnoses of solid malignancies in a Brazilian academic hospital. We reviewed charts and autopsy reports of the patients that died from 2001 to 2003 with at least one solid neoplasm. Patients were classified in concordant and discordant cases regarding cancer diagnosis. Discordant cases were categorized in undiagnosed cases (no suspicion of cancer) and in misdiagnosed cases (clinical suspicion of cancer but incompletely diagnosed). Among the 264 patients with a single non-incidental solid neoplasm, the clinico-pathological discrepancy rate was 37.1%. Liver (22.5%), lung (19.4%), and pancreatic cancer (15.3%) were the most frequent malignancies in the discordant group. Misdiagnosis category comprised 68% of the discordant cases, i.e., there was no correct knowledge about the tumor primary site and/or the histological type during life. Our data show that a high rate of discrepancies occurs in solid malignancies. Autopsies may provide the basis for a better understanding of diagnostic deficiencies in different circumstances. (C) 2008 Elsevier GmbH. All rights reserved.
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Reactive oxygen species oxidize proteins and modulate the proteasomal system in muscle-wasting cancer cachexia. On day 5 (D5), day 10 (D10), and day 14 (D14) after tumor implantation, skeletal muscle was evaluated. Carbonylated proteins and thiobarbituric acid reactive substances were measured. Chemiluminescence was employed for lipid hydroperoxide estimation. Glutathione, superoxide dismutase, and total radical antioxidant capacity were evaluated. The proteasomal system was assessed by mRNA atrogin-1 expression. Increased muscle wasting, lipid hydroperoxide, and superoxide dismutase, and decreased glutathione levels and total radical antioxidant capacity, were found on D5 in accordance with increased mRNA atrogin-1 expression. All parameters were significantly modified in animals treated with alpha-tocopherol. The elevation in aldehylde levels and carbonylated proteins observed on D10 were reversed by cc-tocopherol treatment. Oxidative stress may trigger signal transduction of the proteasomal system and cause protein oxidation. These pathways may be associated with the mechanism of muscle wasting that occurs in cancer cachexia. Muscle Nerve 42: 950-958, 2010
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The interaction between dengue virus particles (DENV), sedimentation hemagglutinin particles (SHA), dengue virus envelope protein (Eprot), and solid surfaces was investigated by means of ellipsometry and atomic force microscopy (AFM). The surfaces chosen are bare Si/SiO(2) wafers and Si/SiO(2) wafers covered with concanavalin A (ConA), jacalin (Jac), polystyrene (PS), or poly(styrene sulfonate) (PSS) films. Adsorption experiments at pH 7.2 and pH 3 onto all surfaces revealed that (i) adsorption of DENV particles took place only onto ConA under pH 7.2, because of specific recognition between glycans on DENV surface and ConA binding site; (ii) DENV particles did not attach to any of the surfaces at pH 3, suggesting the presence of positive charges on DENV surface at this pH, which repel the positively charged lectin surfaces; (iii) SHA particles are positively charged at pH 7.2 and pH 3 because they adhered to negatively charged surfaces at pH 7.2 and repelled positively charged layers at pH 3; and (iv) SHA particles carry polar groups on the surface because they attached to silanol surfaces at pH 3 and avoided hydrophobic PS films at pH 3 and pH 7.2. The adsorption behavior of Eprot at pH 7.2 revealed affinity for ConA > Jac > PSS > PS approximate to bare Si/SiO(2) layers. These findings indicate that selectivity of the Eprot adsorption is higher when it is part of virus structure than when it is free in solution. The correlation between surface energy values determined by means of contact angle measurements and DENV, SHA, or Eprot adsorption behavior was used to understand the intermolecular forces at the interfaces. A direct correlation was not found because the contributions from surface energy were probably surpassed by specific contributions.
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Solid-state C-13 NMR spectroscopy was used to investigate the three-dimensional structure of melittin as lyophilized powder and in ditetradecylphosphatidylcholine (DTPC) membranes. The distance between specifically labeled carbons in analogs [1-C-13]Gly3-[2-C-13]Ala4, [1-C-13]Gly3-[2-C-13]Leu6, [1-C-13]Leu13-[2-C-13]Ala15, [2-C-13]Leu13-[1-C-13]Ala15, and [1-C-13]Leu13-[2-C-13]Leu16 was measured by rotational resonance. As expected, the internuclear distances measured in [1-C-13]Gly3-[2-C-13]Ala4 and [1-C-13]Gly3-[2-C-13]Leu6 were consistent with alpha -helical structure in the N-terminus irrespective of environment. The Internuclear distances measured in [1-C-13]Leu13-[2-C-13]Ala15, [2-C-13]Leu13-[1-C-13]Ala15, and [1-C-13]Leu13-[2-C-13]Leu16 revealed, via molecular modeling, some dependence upon environment for conformation in the region of the bend in helical structure induced by Pro14. A slightly larger interhelical angle between the N- and C-terminal helices was indicated for peptide in dry or hydrated gel state DTPC (139 degrees -145 degrees) than in lyophilized powder (121 degrees -139 degrees) or crystals (129 degrees). The angle, however, is not as great as deduced for melittin in aligned bilayers of DTPC in the liquid-crystalline state (similar to 160 degrees) (R. Smith, F. Separovic, T. J. Milne, A. Whittaker, F. M. Bennett, B. A. Cornell, and A. Makriyannis, 1994, J. Mol, Biol 241:456-466). The study illustrates the utility of rotational resonance in determining local structure within peptide-lipid complexes.
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Mono- and dicopper(II) complexes of a series of potentially bridging hexaamine ligands have been prepared and characterized in the solid state by X-ray crystallography. The crystal structures of the following Cu-II complexes are reported: [Cu(HL3)](ClO4)(3), C11H31Cl3CuN6O12, monoclinic, P2(1)/n, a = 8.294(2) Angstrom, b = 18.364(3) Angstrom, c = 15.674(3) Angstrom, beta = 94.73(2)degrees, Z = 4; {[Cu-2(L-4)(CO3)](2)}(ClO4)(4). 4H(2)O, C40H100Cl4Cu4N12O26, triclinic, P (1) over bar, a = 9.4888(8) Angstrom, b=13.353(1) Angstrom,. c = 15.329(1) Angstrom, alpha = 111.250(7)degrees, beta = 90.068(8)degrees, gamma = 105.081(8)degrees, Z=1; [Cu-2(L-5)(OH2)(2)](ClO4)(4), C(13)H(36)Cl(4)Cu(2)Z(6)O(18), monoclinic, P2(1)/c, a = 7.225(2) Angstrom. b = 8.5555(5) Angstrom, c = 23.134(8) Angstrom, beta = 92.37(1)degrees, Z = 2; [Cu-2(L-6)(OH2)(2)](ClO4)(4). 3H(2)O, C14H44Cl4Cu2N6O21, monoclinic, P2(1)/a, a = 15.204(5) Angstrom, b = 7.6810(7) Angstrom, c = 29.370(1) Angstrom, beta = 100.42(2)degrees, Z = 4. Solution spectroscopic properties of the bimetallic complexes indicate that significant conformational changes occur upon dissolution, and this has been probed with EPR spectroscopy and molecular mechanics calculations.
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The radiation chemistry of FEP copolymer with a mole fraction TFE of 0.90 has been studied using Co-60 gamma -radiation at temperatures of 300 and 363 K. New structure formation in the copolymers was analysed by solid state F-19 NMR. New chain scission products were the principal new structures found. The G-value for the formation of new -CF3 groups was 2.2 and 2.1 for the radiolysis of FEP at 300 and 363 K, respectively, and the G-value for the loss of original -CF3 groups was G(-CF3) = 1.0 and 0.9 at these two temperatures, respectively. There was a nett loss of -CF- groups on irradiation, with G(-CF) of 1.3 and 0.9 at 300 and 363 K, respectively. (C) 2001 Elsevier Science Ltd. All rights reserved.
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We consider the statistical properties of the local density of states of a one-dimensional Dirac equation in the presence of various types of disorder with Gaussian white-noise distribution. It is shown how either the replica trick or supersymmetry can be used to calculate exactly all the moments of the local density of states.' Careful attention is paid to how the results change if the local density of states is averaged over atomic length scales. For both the replica trick and supersymmetry the problem is reduced to finding the ground state of a zero-dimensional Hamiltonian which is written solely in terms of a pair of coupled spins which are elements of u(1, 1). This ground state is explicitly found for the particular case of the Dirac equation corresponding to an infinite metallic quantum wire with a single conduction channel. The calculated moments of the local density of states agree with those found previously by Al'tshuler and Prigodin [Sov. Phys. JETP 68 (1989) 198] using a technique based on recursion relations for Feynman diagrams. (C) 2001 Elsevier Science B.V. All rights reserved.
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A remarkable feature of quantum entanglement is that an entangled state of two parties, Alice (A) and Bob (B), may be more disordered locally than globally. That is, S(A) > S(A, B), where S() is the von Neumann entropy. It is known that satisfaction of this inequality implies that a state is nonseparable. In this paper we prove the stronger result that for separable states the vector of eigenvalues of the density matrix of system AB is majorized by the vector of eigenvalues of the density matrix of system A alone. This gives a strong sense in which a separable state is more disordered globally than locally and a new necessary condition for separability of bipartite states in arbitrary dimensions.
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The application of the N-1-(4,4-dimethyl-2,6-dioxocyclohexylidene)ethyl (Dde) linker for the solid-phase synthesis of oligosaccharides is described. The oligosaccharide products can be cleaved from the resin by hydrazine, ammonia or primary amines, but the linker is stable under the conditions of oligosaccharide synthesis. The first sugar can be attached to the resin linker via a vinylogous amide bond, or by ether linkage using a p-aminobenzyl alcohol converter. (C) 2001 Elsevier Science Ltd. All rights reserved.
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A 250 mum diameter fibre of ytterbium-doped ZBLAN was cooled by 13 K from room temperature. The cooling was performed in vacuum to limit the thermal load on the fibre. 0.85 W of laser light at 1015 nm was coupled into the fibre. The ytterbium ions absorbed this light, and the excited atoms thermalized phononically and on average emitted light at a wavelength of 996 nm. Since the quantum efficiency of the transition was high, this resulted in a net loss of energy from the glass, producing net bulk cooling.
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Some efficient solution techniques for solving models of noncatalytic gas-solid and fluid-solid reactions are presented. These models include those with non-constant diffusivities for which the formulation reduces to that of a convection-diffusion problem. A singular perturbation problem results for such models in the presence of a large Thiele modulus, for which the classical numerical methods can present difficulties. For the convection-diffusion like case, the time-dependent partial differential equations are transformed by a semi-discrete Petrov-Galerkin finite element method into a system of ordinary differential equations of the initial-value type that can be readily solved. In the presence of a constant diffusivity, in slab geometry the convection-like terms are absent, and the combination of a fitted mesh finite difference method with a predictor-corrector method is used to solve the problem. Both the methods are found to converge, and general reaction rate forms can be treated. These methods are simple and highly efficient for arbitrary particle geometry and parameters, including a large Thiele modulus. (C) 2001 Elsevier Science Ltd. All rights reserved.