RESUMO
The recent discovery of superconductivity in oxypnictides with a critical transition temperature (T(C)) higher than the McMillan limit of 39 K (the theoretical maximum predicted by Bardeen-Cooper-Schrieffer theory) has generated great excitement. Theoretical calculations indicate that the electron-phonon interaction is not strong enough to give rise to such high transition temperatures, but strong ferromagnetic/antiferromagnetic fluctuations have been proposed to be responsible. Superconductivity and magnetism in pnictide superconductors, however, show a strong sensitivity to the crystal lattice, suggesting the possibility of unconventional electron-phonon coupling. Here we report the effect of oxygen and iron isotope substitution on T(C) and the spin-density wave (SDW) transition temperature (T(SDW)) in the SmFeAsO(1 - x)F(x) and Ba(1 - x)K(x)Fe(2)As(2) systems. The oxygen isotope effect on T(C) and T(SDW) is very small, while the iron isotope exponent alpha(C) = -dlnT(C)/dlnM is about 0.35 (0.5 corresponds to the full isotope effect). Surprisingly, the iron isotope exchange shows the same effect on T(SDW) as T(C). This indicates that electron-phonon interaction plays some role in the superconducting mechanism, but a simple electron-phonon coupling mechanism seems unlikely because a strong magnon-phonon coupling is included.
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Tuning the metal insulator transition (MIT) behavior of VO2 film through the interfacial strain is effective for practical applications. However, the mechanism for strain-modulated MIT is still under debate. Here we directly record the strain dynamics of ultrathin VO2 film on TiO2 substrate and reveal the intrinsic modulation process by means of synchrotron radiation and first-principles calculations. It is observed that the MIT process of the obtained VO2 films can be modulated continuously via the interfacial strain. The relationship between the phase transition temperature and the strain evolution is established from the initial film growth. From the interfacial strain dynamics and theoretical calculations, we claim that the electronic orbital occupancy is strongly affected by the interfacial strain, which changes also the electron-electron correlation and controls the phase transition temperature. These findings open the possibility of an active tuning of phase transition for the thin VO2 film through the interfacial lattice engineering.
RESUMO
BACKGROUND: Genetically modified organisms (GMOs) provide modern agriculture with improvements in efficiency and the benefits of enhanced food production; however, the potential impact of GMOs on human health has not yet been clarified. OBJECTIVE: To investigate the allergenicity of isopentenyltransferase (ipt)-transformed broccoli compared with non-GM broccoli. METHODS: Sera from allergic individuals were used to identify the allergenicity of GM and non-GM broccoli. Immunoglobulin (Ig) binding of different lines of GM and non-GM broccoli was identified using immunoblotting, enzyme-linked immunosorbent assay, and the histamin release assay. RESULTS: Positive reactions to broccoli (Brassica Oleracea) were observed in 7.02% of individuals. Specific IgE to broccoli and total IgE fro allergic individuals were well correlated. The different tests performed showed no significant differences in the allergenicity of conventionally raised and GM broccoli, indicating the absence of unexpected effects on allergenicity in ipt-transformed plants. Using Western blot analysis we detected heterogeneous IgE-reactive allergenic components in broccoli-allergic sera, but no significant differences between GM an non-GM broccoli were observed in serum from the same patients. CONCLUSIONS: Our study demonstrates that there are no differences between GM (ipt-transformed) broccoli and non-GM broccoli, as determined by specific IgE in sera from broccoli-allergic patients. This indicates that there were no unexpected effects on allergenicity in this GM broccoli.
Assuntos
Alquil e Aril Transferases/sangue , Alérgenos/sangue , Brassica/imunologia , Hipersensibilidade Alimentar/sangue , Imunoglobulina E/sangue , Proteínas de Plantas/sangue , Plantas Geneticamente Modificadas/imunologia , Adulto , Alquil e Aril Transferases/imunologia , Alérgenos/imunologia , Animais , Brassica/enzimologia , Brassica/genética , Feminino , Hipersensibilidade Alimentar/imunologia , Alimentos Geneticamente Modificados , Heterogeneidade Genética , Histamina/sangue , Histamina/imunologia , Humanos , Imunoensaio , Imunoglobulina E/imunologia , Masculino , Proteínas de Plantas/imunologia , Plantas Geneticamente Modificadas/enzimologia , Plantas Geneticamente Modificadas/genética , Pyroglyphidae/imunologiaRESUMO
Ba(1-x)K(x)Fe(2)As(2) superconducting samples (x = 0, 0.2, 0.4, 0.5) were synthesized by the solid-state reaction method. In this contribution the doping effect of potassium on the lattice dynamics in this newly discovered Ba(1-x)K(x)Fe(2)As(2) superconductor has been investigated by extended X-ray absorption fine-structure spectroscopy. The analysis shows that with potassium doping an increased disorder in the iron layers is mainly related to the softening of the Fe-Fe bond. Information about the electronic structure of these materials has also been obtained by looking at the X-ray absorption near-edge structure spectra that point out the presence of holes in the Fe-3d/As-4p hybridized orbital of the BaFe(2)As(2)-based system.
RESUMO
Lattice vibrational property has been determined in ZrB(2) system using the temperature-dependent extended X-ray-absorption fine-structure (EXAFS) technique from room temperature to 28K. The smooth behavior of Debye-Waller factor curve with temperature is slightly abnormal for the first pair Zr-B. In order to reproduce this curve, an improved Einstein mode with two Einstein frequencies has been used. The quantitative analysis of temperature-dependent Debye-Waller factor of Zr-B pair shows one Einstein frequency is very high and the other is small. These frequencies correspond to the vibration of boron layer atoms and transition-metal layer atoms, respectively. Based on the Einstein mode with one frequency, the vibrational frequency for Zr-Zr pair has been also obtained. Zirconium diboride has two types of Zr-Zr interaction. One is in-plane and the other is out-of-plane along the high symmetry axis. Our analysis shows there is a little difference between in-plane Zr-Zr vibration and out-of-plane one. And the smaller Einstein vibrational frequency for the Zr-B shell is just between the two ones of the Zr-Zr shells. Our results show that the lattice vibrational behavior in ZrB(2) presents obvious particularity and anisotropy.
Assuntos
Compostos de Boro/química , Elementos de Transição/química , Vibração , Zircônio/química , Análise de Fourier , Análise Espectral , TemperaturaRESUMO
This research addresses the development and in vitro evaluation of lipid nanoparticle (NP)-based dressings to optimize the delivery of human recombinant epidermal growth factor (rhEGF) for the topical treatment of chronic wounds. The systems investigated were rhEGF-loaded solid lipid nanoparticles (rhEGF-SLN) and rhEGF-loaded nanostructured lipid carriers (rhEGF-NLC) formulated in wound dressings comprising either semi-solid hydrogels or fibrin-based solid scaffolds. Following detailed characterisation of the NP, in vitro diffusion cell experiments (coupled with dermatopharmacokinetic measurements), together with confocal microscopic imaging, conducted on both intact skin samples, and those from which the barrier (the stratum corneum) had been removed, revealed that (a) the particles remained essentially superficially located for at least up to 48h post-application, (b) rhEGF released on the surface of intact skin was unable to penetrate to the deeper, viable layers, and (c) sustained release of growth factor from the NP "drug reservoirs" into barrier-compromised skin was observed. There were no significant differences between the in vitro performance of rhEGF-SLN and rhEGF-NLC, irrespective of the formulation employed. It is concluded that, because of their potentially longer-term stability, the fibrin-based scaffolds may be the most suitable approach to formulate rhEGF-loaded lipid nanoparticles.
Assuntos
Lipídeos/química , Nanopartículas/química , Pele/metabolismo , Ferimentos e Lesões/tratamento farmacológico , Administração Tópica , Animais , Bandagens , Química Farmacêutica/métodos , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/química , Fator de Crescimento Epidérmico/administração & dosagem , Fator de Crescimento Epidérmico/química , Feminino , Fibrina/metabolismo , Hidrogéis/administração & dosagem , Hidrogéis/química , Lipídeos/administração & dosagem , Nanopartículas/administração & dosagem , Nanoestruturas/administração & dosagem , Nanoestruturas/química , Absorção Cutânea , Suínos , Ferimentos e Lesões/metabolismoRESUMO
Breast cancer cell lines vary in invasive behavior and one highly invasive cell line (MDA-MB-231) proteolytically degrades extracellular matrix with invadopodia (Thompson et al. 1992, J Cell Physiol, 150, 534-44; Chen et al 1994, Breast Cancer Res Treat, 31, 217-26). Invadopodial proteolysis of extracellular matrix is thought to be necessary for invasion; however, this has not been demonstrated directly. To obtain such evidence, normal (HBL-100) and malignant (MCF-7, MDA-MB-231) breast cells were evaluated for invadopodial proteolysis of extracellular matrix and invasive behavior. We report that invadopodial proteolysis of immobilized fibronectin is positively correlated with invasion of cells into type I collagen gels. Moreover, reducing the proteolytic activity of invadopodia with the metalloproteinase inhibitor, batimastat (BB-94), also decreases invasion indicating that breast cancer cell invasion is dependent upon proteolytically active invadopodia.
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Neoplasias da Mama/enzimologia , Matriz Extracelular/metabolismo , Metaloendopeptidases/metabolismo , Invasividade Neoplásica , Proteínas de Neoplasias/metabolismo , Neoplasias da Mama/patologia , Colágeno/metabolismo , Inibidores Enzimáticos/farmacologia , Matriz Extracelular/patologia , Feminino , Fibronectinas/metabolismo , Humanos , Metaloendopeptidases/antagonistas & inibidores , Invasividade Neoplásica/prevenção & controle , Proteínas de Neoplasias/antagonistas & inibidores , Fenilalanina/análogos & derivados , Fenilalanina/farmacologia , Pseudópodes/metabolismo , Tiofenos/farmacologia , Células Tumorais Cultivadas/efeitos dos fármacosRESUMO
Diabetic nephropathy is the leading cause of end-stage renal disease worldwide. Although death rates of diabetic patients on hemodialysis and peritoneal dialysis (PD) have decreased substantially, they remain higher than rates in nondiabetics on both modalities. PD offers equal or better survival than hemodialysis for younger diabetic patients during early years of dialysis. PD technique survival does not appear different between diabetic and nondiabetic patients but is inferior to hemodialysis technique survival. PD may accelerate changes in peritoneal membrane structure and function in diabetics. Peritonitis and conventional PD solutions containing high glucose and glucose degradation products are implicated in PD technique failure. Increased peritoneal expression of vascular endothelial growth factor and transforming growth factor-beta1 and excessive accumulation of advanced glycosylation end products may be involved in the progressive increase in membrane permeability, loss of ultrafiltration, and peritoneal fibrosis. Nonglucose PD solutions or solutions containing low glucose degradation products may prevent or delay alterations in peritoneal membrane structure and function in diabetic as well as nondiabetic patients during long-term PD.
Assuntos
Nefropatias Diabéticas/terapia , Diálise Peritoneal/efeitos adversos , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/mortalidade , Fatores de Crescimento Endotelial/metabolismo , Feminino , Produtos Finais de Glicação Avançada/metabolismo , Humanos , Tempo de Internação/estatística & dados numéricos , Linfocinas/metabolismo , Masculino , Pessoa de Meia-Idade , Diálise Peritoneal Ambulatorial Contínua , Diálise Renal , Fatores de Risco , Taxa de Sobrevida , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta1 , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio VascularRESUMO
Small lymphocytic lymphoma (SLL) and mantle cell lymphoma (MCL) are small B-cell lymphomas that share many morphological and immunophenotypic features, both expressing the T-cell antigen CD5. Because of this, there is speculation that these two lymphomas may have a common origin, both arising from the mantle zone of the lymph node. CD44 (HCAM), a glycoprotein "homing receptor," has been reported as a marker of small B-cell lymphomas for determining behavior as well as the nodal cell of origin. Intensity of CD44 expression also has been correlated with dissemination of lymphoma. We studied 50 cases with classic features of SLL (30 cases) or MCL (20 cases). Immunophenotypic analysis was performed on paraffin sections. All cases of MCL and SLL were CD20 positive; CD5 was expressed in 19 of 25 (76%) SLL and 11 of 15 (73%) MCL. Cyclin D1 was expressed in 11 of 17 (76%) MCL and no cases of SLL. CD43 coexpression was seen in 27 of 29 (93%) SLL and 17 of 19 (89%) MCL. CD23 was positive in 25 of 28 (89%) SLL and 2 of 20 (10%) MCL. Bcl-2 was positive in 18 of 22 (82%) SLL and 15 of 16 (94%) MCL. CD44 was positive with moderate to strong intensity in 11 of 30 SLL and 15 of 20 MCL. Peripheral blood involvement did not correlate with CD44 immunoreactivity. MCL tended to have intense CD44 immunoreactivity, whereas SLL tended to show weaker CD44 intensity. This trend in the intensity of CD44 in MCL suggests that CD44 may be helpful in distinguishing SLL from MCL and possibly elucidating the origin of these CD5-positive B-cell neoplasms.
Assuntos
Receptores de Hialuronatos/biossíntese , Leucemia Linfocítica Crônica de Células B/metabolismo , Linfoma não Hodgkin/metabolismo , Adulto , Idoso , Feminino , Humanos , Imuno-Histoquímica , Imunofenotipagem , Leucemia Linfocítica Crônica de Células B/patologia , Linfoma não Hodgkin/patologia , Masculino , Pessoa de Meia-IdadeRESUMO
Inhibitors of apoptosis may regulate tissue differentiation and promote cell survival in neoplasia. A new apoptosis inhibitor of the bcl-2 gene family, bcl-X(L), was recently found in some types human neoplasia but not in normal tissue. We investigated bcl-X(L) expression in 419 cases of normal and neoplastic lymphoid lesions using immunohistochemistry with the monoclonal antibody bcl-X(L) (YTH-2H12). Ninety-four percent (141/150) of classic Hodgkin's disease (HD) were positive for bcl-X(L) with strong intensity in most Reed-Sternberg (RS) cells. Forty-eight percent (38/80) of nodular lymphocyte predominance (LPHD) were positive. In the non-Hodgkin's lymphomas (NHL), bcl-X(L) was expressed in a low percentage of cases (< 20%), with the exception of follicle center lymphoma, grade III/III (78%). All reactive hyperplastic lesions were negative for bcl-X(L). RS cells, which expressed bcl-X(L), were not labeled by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL). We found RS cells expressing bcl-X(L) were absent of DNA fragmentation (apoptosis). Our data provide evidence that bcl-X(L) is abnormally expressed in the RS cells of HD and some types of NHL raising speculation that inhibition of apoptosis may be important in the pathogenesis of lymphoma, specifically HD. In addition, the previously reported correlation between bcl-X(L) and Epstein-Barr virus expression in HD was not supported by this study.
Assuntos
Anticorpos Monoclonais/imunologia , Apoptose , Biomarcadores Tumorais/biossíntese , Doença de Hodgkin/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Células de Reed-Sternberg/metabolismo , Animais , Linfoma de Burkitt/metabolismo , Linfoma de Burkitt/patologia , Herpesvirus Humano 4/isolamento & purificação , Doença de Hodgkin/patologia , Humanos , Immunoblotting , Imuno-Histoquímica , Hibridização In Situ , Mononucleose Infecciosa/metabolismo , Linfoma não Hodgkin/metabolismo , Linfoma não Hodgkin/patologia , Linfoma de Células T/metabolismo , Linfoma de Células T/patologia , Camundongos , Proteínas Proto-Oncogênicas c-bcl-2/imunologia , Células de Reed-Sternberg/patologia , Células Tumorais Cultivadas , Proteínas da Matriz Viral/metabolismo , Proteína bcl-XRESUMO
The bcl-2 gene is implicated in oncogenesis by its ability to prolong cell survival through the inhibition of apoptosis, without increasing cell proliferation. An association between immunohistochemical staining for bcl-2 protein and the histological type and prognosis of non-small cell carcinoma was hypothesized by Pezzella et al. (N Engl J Med 329:690-694, 1993). In a case series, we stained formalin-fixed, paraffin-embedded tumor tissue from 106 surgical non-small cell lung cancer patients with an antibody to bcl-2 protein (DAKO clone 124, Carpinteria, CA). The resulting bcl-2 staining data were evaluated for associations with demographic, histological, immunohistochemical, and genetic features, including p53 mutations. Bcl-2 staining was observed in tumors from 29 of 106 (27%) of subjects, but was significantly less frequent in subjects' adenocarcinoma histology (8 of 55, 14.6%) (P = .007). This finding persisted after adjustment for age, gender, stage, grade, smoking history, and disease-free survival. In univariate analyses, no association was seen with age, weight, body mass index, gender, or pack-years smoking; tumor grade, stage, or patient performance status; p53 or c-erbB2 immunohistochemical staining, or p53 mutations. These data agree with earlier reports that bcl-2 staining is less common in adenocarcinomas; however, our data do not support the hypothesis that bcl-2 staining confers a better prognosis overall, in squamous cell carcinoma, or in an older patient population.
Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Neoplasias Pulmonares/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/análise , Adenocarcinoma/metabolismo , Carcinoma de Células Grandes/metabolismo , Carcinoma de Células Escamosas/metabolismo , Feminino , Genes p53/genética , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Receptor ErbB-2/metabolismo , Proteína Supressora de Tumor p53/análiseRESUMO
Amyloidosis in its diverse types (immunocytic dyscrasia-associated, reactive, or heredofamilial) most often presents in a systemic form. Localized amyloidosis is uncommon in general and is exceedingly rare in the soft tissues. The authors discuss the cases of 14 patients in whom amyloidosis manifested as a localized mass ("amyloidoma") in the soft tissues (mostly mediastinal and retroperitoneal), leading to a clinical diagnosis of neoplasm in most cases. On the basis of the associated morphologically atypical and phenotypically monoclonal cell population, the resistance to potassium permanganate pretreatment, and the lack of reactivity with anti-AA antisera, 10 cases could be classified as immunocytic dyscrasia-associated AL-amyloidosis. However, four cases had histopathologic and histo- and immunohistochemical characteristics of reactive ("secondary") AA-amyloidosis. This proportion (28.5%) was higher than that suggested by the sporadic AA-amyloidomas reported in the literature. The pathologic distinction between these two categories is important because patients with AA-amyloidomas of the soft tissues appear to have a better prognosis.
Assuntos
Amiloidose/patologia , Neoplasias de Tecidos Moles/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Amiloidose/metabolismo , Feminino , Histocitoquímica , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Neoplasias de Tecidos Moles/metabolismoRESUMO
The authors investigated the relations between outcome and apoptosis, immunohistochemical demonstration of bcl-2 protein, and immunohistochemical staining for p53 protein in patients with gastrointestinal stromal/smooth muscle tumors (GIST). Patients whose tumors demonstrated cellular apoptosis using the terminal deoxynucleotidyl transferase-mediated 2'-deoxyuridine 5'-triphosphate-biotin nick end labeling (TUNEL) assay had an improved survival over those whose tumors did not improve. In contrast, patients whose tumors demonstrated staining for bcl-2 protein had a decreased survival compared with those whose tumors did not demonstrate bcl-2. There was no relation between p53 immunoreactivity and survival. These results suggest that inhibition of apoptosis may be associated with malignant behavior in patients with gastrointestinal stromal/smooth muscle tumors.
Assuntos
Apoptose , Neoplasias Gastrointestinais/metabolismo , Neoplasias Gastrointestinais/patologia , Neoplasias de Tecido Muscular/metabolismo , Neoplasias de Tecido Muscular/patologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Humanos , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Leiomioma/metabolismo , Leiomioma/patologia , Leiomiossarcoma/metabolismo , Leiomiossarcoma/patologia , Índice Mitótico , Neoplasias de Tecido Conjuntivo/metabolismo , Neoplasias de Tecido Conjuntivo/patologiaRESUMO
CONTEXT: c-kit, a proto-oncogene, encodes the transmembrane tyrosine kinase receptor CD117 and is detected by flow cytometry in the majority of cases of acute myeloid leukemia. The prognostic significance of the presence of c-Kit in acute myeloid leukemia is debated. Recently, c-kit inhibitors have been studied as possible therapies against hematopoietic malignancies; therefore, c-Kit detection may have important implications for treatment. OBJECTIVES: In this study, we investigated the expression of c-Kit in granulocytic sarcoma (GS) using paraffin-embedded tissue. DESIGN: Routinely formalin-fixed, paraffin-embedded tissues from 30 cases of GS were studied using immunohistochemistry. c-Kit (C-19) (a polyclonal antibody against carboxy terminal domain of c-Kit p145 or CD117) reactivity was compared with myeloperoxidase and lysozyme. The immunohistochemical panel also included CD34, CD68, CD43, Bcl-2, CD45RB, CD20, CD3, CD10, terminal deoxynucleotidyl transferase (TdT), and CD79a. RESULTS: The morphologic patterns included well-differentiated (5 cases), poorly differentiated (19 cases), and blastic forms (6 cases). Clinical data were obtained from 28 of 30 patients. Granulocytic sarcoma presented in lymph nodes in 10 cases, whereas in 20 cases it presented in extranodal sites. c-Kit reactivity was found in 87% (26/30) of the GS cases. There was no significant difference in c-Kit positivity between the nodal (90%, 9/10) and extranodal (85%, 17/20) neoplasms. c-Kit expression was not associated with the degree of the myeloid maturation. Two of 13 lymphoblastic lymphoma control cases and 1 of 28 of the large B-cell lymphomas were weakly immunoreactive with c-Kit. CONCLUSIONS: c-Kit reactivity can be demonstrated in a high percentage of GS cases; its presence may be useful not only in diagnosis, but also in the treatment of GS with new modalities.
Assuntos
Granulócitos/imunologia , Proteínas Proto-Oncogênicas c-kit/análise , Sarcoma/imunologia , Adolescente , Adulto , Idoso , Biomarcadores Tumorais , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Criança , Diagnóstico Diferencial , Feminino , Granulócitos/patologia , Humanos , Imuno-Histoquímica , Neoplasias Intestinais/imunologia , Neoplasias Intestinais/patologia , Intestino Delgado , Leucemia Mieloide/imunologia , Leucemia Mieloide/patologia , Linfonodos/patologia , Masculino , Pessoa de Meia-Idade , Proto-Oncogene Mas , Sarcoma/patologia , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/patologia , Neoplasias Testiculares/imunologia , Neoplasias Testiculares/patologiaRESUMO
CONTEXT: Inflammatory pseudotumor is an uncommon and enigmatic lesion. The spindle cells found in this tumor have features of myofibroblasts. Because of the indefinite relationship of these lesions with inflammatory fibrosarcoma and their indefinite biologic behavior, inflammatory pseudotumor is currently classified as inflammatory myofibroblastic tumor (IMT). To date, only case reports or small series have been published on these tumors, which are primary in the spleen. DESIGN: In this study, we describe the clinical, morphologic, and immunophenotypic findings of 12 cases of splenic IMT and examine their relationship to Epstein-Barr virus (EBV). RESULTS: The patients included 8 women and 3 men, ranging from 19 to 77 years of age (mean, 53 years; median, 60 years). Demographic data were unavailable for 1 patient. Patients generally presented with abdominal pain (n = 5) and fever (n = 4). Associated lesions included renal cell carcinoma (n = 2), colonic adenocarcinoma (n = 1), and cholecystitis (n = 1). All tumors were composed of a bland spindle cell proliferation in association with a variable mixed inflammatory component. There were 2 growth patterns, namely, a cellular spindle cell pattern and a hypocellular fibrous pattern. An immunohistochemical panel confirmed the myofibroblastic nature of the spindle cells. The spindle cells of 2 cases were immunoreactive for EBV latent membrane protein 1, whereas 6 of 10 cases were positive for EBV-encoded RNA using in situ hybridization. Follow-up was available for 8 patients; 6 were alive with no evidence of recurrence and 2 were dead of other causes. CONCLUSION: Splenic IMTs are uncommon lesions that can be distinguished from other conditions using a combination of clinical, histologic, and immunophenotypic findings. Epstein-Barr virus may play a role in the pathogenesis of splenic IMT, and there may be an association of splenic IMT with concomitant disease or malignancy. Most splenic IMTs have an excellent long-term prognosis.
Assuntos
Granuloma de Células Plasmáticas/patologia , Neoplasias Esplênicas/patologia , Adulto , Idoso , Biomarcadores Tumorais/análise , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/patologia , Feminino , Seguimentos , Granuloma de Células Plasmáticas/imunologia , Granuloma de Células Plasmáticas/cirurgia , Granuloma de Células Plasmáticas/virologia , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/isolamento & purificação , Herpesvirus Humano 4/patogenicidade , Humanos , Técnicas Imunoenzimáticas , Imunofenotipagem , Hibridização In Situ , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/análise , Neoplasias Primárias Múltiplas/patologia , RNA Viral/análise , Neoplasias Esplênicas/imunologia , Neoplasias Esplênicas/cirurgia , Neoplasias Esplênicas/virologia , Resultado do TratamentoRESUMO
BACKGROUND: In continuous ambulatory peritoneal dialysis (CAPD), the peritoneal membrane is continuously exposed to high-glucose-containing dialysis solutions. Abnormally high glucose concentration in the peritoneal cavity may enhance advanced glycosylation end-product (AGE) formation and accumulation in the peritoneum. Increased AGE accumulation in the peritoneum, decreased ultrafiltration volume, and increased peritoneal permeability in long-term dialysis patients have been reported. AIM: The purpose of the study was to evaluate the relation between peritoneal membrane permeability and peritoneal accumulation of AGE. METHODS: Peritoneal membrane permeability was evaluated by peritoneal equilibration test (PET) using dialysis solutions containing 4.25% glucose. Serum, dialysate, and peritoneal tissue levels of AGE were measured by ELISA method using polyclonal anti-AGE antibody. Peritoneal biopsy was performed during peritoneal catheter insertion [new group (group N), n = 18] and removal [long-term group (group LT), n = 10]. Peritoneal catheters were removed due to exit-site infection not extended into the internal cuff (n = 6) and ultrafiltration failure (n = 4) after 51.6+/-31.5 months (13 - 101 months) of dialysis. PET data obtained within 3 months after the initiation of CAPD or before catheter removal were included in this study. Ten patients in group N and 4 patients in group LT were diabetic. Patients in group LT were significantly younger (46.5+/-11.1 years vs 57.5+/-1.3 years) and experienced more episodes of peritonitis (3.5+/-2.1 vs 0.2+/-0.7) than group N. RESULTS: Peritoneal tissue AGE level in group LT was significantly higher than in group N, in both nondiabetic (0.187+/-0.108 U/mg vs 0.093+/-0.08 U/mg of hydroxyproline, p < 0.03) and diabetic patients (0.384+/-0.035 U/mg vs 0.152+/-0.082 U/mg of hydroxyproline, p < 0.03), while serum and dialysate levels did not differ between the groups in both nondiabetic and diabetic patients. Drain volume (2600+/-237 mL vs 2766+/-222 mL, p = 0.07) and D4/D0 glucose (0.229+/-0.066 vs 0.298+/-0.081, p < 0.009) were lower, and D4/P4 creatinine (0.807+/-0.100 vs 0.653+/-0.144, p< 0.0001) and D1/P1 sodium (0.886+/-0.040 vs 0.822+/-0.032, p < 0.0003) were significantly higher in group LT than in group N. On linear regression analysis, AGE level in the peritoneum was directly correlated with duration of CAPD (r = 0.476, p = 0.012), number of peritonitis episodes (r = 0.433, p = 0.0215), D4/P4 creatinine (r = 0.546, p < 0.027), and D1/P1 sodium (r = 0.422, p = 0.0254), and inversely correlated with drain volume (r = 0.432, p = 0.022) and D4/D0 glucose (r = 0.552, p < 0.0023). AGE level in the peritoneal tissue and dialysate were significantly higher in diabetics than in nondiabetics in group LT, while these differences were not found in group N. Serum AGE level did not differ between nondiabetics and diabetics in either group N or group LT. Drain volume and D4/D0 glucose were lower and D4/P4 creatinine and D1/P1 sodium higher in diabetics than in nondiabetics in both groups. CONCLUSION: Peritoneal accumulation of AGE increased with time on CAPD and number of peritonitis episodes, and was directly related with peritoneal permeability. Peritoneal AGE accumulation and peritoneal permeability in diabetic patients were higher than in nondiabetic patients from the beginning of CAPD.
Assuntos
Produtos Finais de Glicação Avançada/metabolismo , Membranas Artificiais , Diálise Peritoneal Ambulatorial Contínua , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , PermeabilidadeRESUMO
OBJECTIVE: To evaluate the influence of initial peritoneal transport rate, serum albumin concentration, and comorbid diseases on continuous ambulatory peritoneal dialysis (CAPD) patient survival. DESIGN: A prospective single-center study with a long-term follow-up. PATIENTS: A total of 213 consecutive CAPD patients, who underwent a peritoneal equilibration test (PET) at a mean of 7 days (range 3 - 30 days) after beginning CAPD, were included in this study. One hundred twenty patients were male, 116 patients had comorbid diseases, and mean age was 49.5 years (range 18 - 76 years). METHODS: A modified PET was performed using 4.25% glucose dialysis solution. Based on the dialysate-to-plasma creatinine concentration ratio at 4 hours' dwell (D4/P4 Cr, 0.62 +/- 0.14), patients were divided into high (H), high-average (HA), low-average (LA), or low (L) transporters. RESULTS: Of 213 patients, 16.9% were classified as H transporters, 30.5% as HA, 36.6% as LA, and 16.0% as L transporters. The H transporter group had a higher proportion of men, higher proportion of patients with comorbid diseases, lower initial serum albumin concentration, lower D4/D0 glucose, and lower drained volume. The initial D4/P4 Cr correlated with initial serum albumin (r= -0.35, p < 0.001). The patients with comorbid diseases had lower initial serum albumin and higher initial D4/P4 Cr. On Kaplan-Meier analysis, 2-year patient survival of group H was significantly lower compared to the other groups combined (57.1% vs 79.5%, p = 0.009). On Cox proportional hazards analysis, age, comorbid diseases, initial serum albumin concentration, and initial D4/P4 Cr were found to be independent risk factors for mortality. However, in the patients without comorbid diseases, patient survival was not different between group H and the other transport groups combined (p > 0.05), and only age was found to be an independent risk factor for mortality. CONCLUSION: These data suggest that a high peritoneal transport rate at initial PET is associated with high mortality, and that this is in part due to an increased prevalence of comorbid disease in H transporters. These H transporters with comorbid diseases represent a subset of patients with an especially poor prognosis. In patients without comorbid diseases, high transport status or low serum albumin concentration was not an independent risk factor for mortality.
Assuntos
Doenças Cardiovasculares/epidemiologia , Diabetes Mellitus/epidemiologia , Falência Renal Crônica/epidemiologia , Hepatopatias/epidemiologia , Diálise Peritoneal Ambulatorial Contínua/mortalidade , Diálise Peritoneal Ambulatorial Contínua/métodos , Doenças Respiratórias/epidemiologia , Albumina Sérica/análise , Adolescente , Adulto , Distribuição por Idade , Idoso , Análise de Variância , Comorbidade , Feminino , Humanos , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Medição de Risco , Distribuição por Sexo , Análise de SobrevidaRESUMO
OBJECTIVES: To assess the nutritional status of Korean peritoneal dialysis (PD) patients and to compare with data from Western literature, and to elucidate independent factors determining nutritional status and death. DESIGN: Cross-sectional single-center study. SETTING: Kidney Center, Soon Chun Hyang University Hospital. MATERIALS: Ninety-eight CAPD patients were included. Of these, 54 patients were male, 32 patients were diabetic, mean age was 47.9+/-13.1 years, and mean duration of CAPD was 22.3+/-21.6 months. The patients were followed until death, transfer to hemodialysis (HD) or other units, transplantation, or until 3 years had elapsed after the first evaluation. METHODS: Nutritional status was assessed by subjective global assessment (SGA), biochemical and anthropometric measurements, fat-free edema-free (FFEF) body mass by creatinine (Cr) kinetics, protein equivalent of total nitrogen appearance (PNA), and urea kinetic studies. RESULTS: By SGA score, 53.1% of patients were classified as normal, 44.9% with mild-to-moderate malnutrition, and 2% with severe malnutrition. Patients with malnutrition were significantly older and had higher peritonitis rates, lower serum albumin (Alb), blood urea nitrogen (BUN), serum Cr, FFEF body mass, mid arm muscle circumference, and PNA (p < 0.05). On stepwise multiple regression analysis, the SGA score was negatively correlated with age and peritonitis rate (p < 0.01). At the end of the 3-year follow-up period, 11 patients were still on CAPD, 26 had died, 51 had transferred to HD and 5 to other units, 3 patients had been transplanted, and 2 patients were lost to follow-up. Patients who died during follow-up were older and had higher peritonitis rates and lower total serum protein, Alb, Cr, and FFEF body mass when compared to those who survived (p < 0.05). Independent predictors of death were age, peritonitis rate, and serum Alb (p < 0.01). CONCLUSION: Malnutrition was as common in Korean PD patients as reported in the Western literature. Our data suggests that, to prevent malnutrition and early death, it is important to reduce the peritonitis rate, to improve protein intake, and to prescribe an adequate dose of peritoneal dialysis.
Assuntos
Estado Nutricional , Diálise Peritoneal , Antropometria , Estudos Transversais , Feminino , Humanos , Falência Renal Crônica/etiologia , Falência Renal Crônica/metabolismo , Falência Renal Crônica/terapia , Coreia (Geográfico) , Masculino , Pessoa de Meia-Idade , Distúrbios Nutricionais/diagnóstico , Distúrbios Nutricionais/etiologia , Diálise Peritoneal/efeitos adversos , Diálise Peritoneal Ambulatorial Contínua , Proteínas/metabolismo , Fatores de Risco , Ureia/metabolismoRESUMO
Pressure-induced amorphous-to-amorphous configuration changes in Ca-Al metallic glasses (MGs) were studied by performing in-situ room-temperature high-pressure x-ray diffraction up to about 40â GPa. Changes in compressibility at about 18â GPa, 15.5â GPa and 7.5â GPa during compression are detected in Ca(80)Al(20), Ca(72.7)Al(27.3), and Ca(66.4)Al(33.6) MGs, respectively, whereas no clear change has been detected in the Ca(50)Al(50) MG. The transfer of s electrons into d orbitals under pressure, reported for the pressure-induced phase transformations in pure polycrystalline Ca, is suggested to explain the observation of an amorphous-to-amorphous configuration change in this Ca-Al MG system. Results presented here show that the pressure induced amorphous-to-amorphous configuration is not limited to f electron-containing MGs.