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101.
Herrera MF Velázquez D Bezauri P Angeles-Angeles A Uscanga LF Robles-Díaz G 《Gaceta médica de México》2003,139(1):21-25
Computarized tomography allows proper identification and evaluation of stage in the majority patients with periampullary tumors. However, 30% of peritoneal metastases cannot be seen in image studies. The aim of the present study was to evaluate the role of laparoscopy with laparoscopic ultrasound in the staging process of pancreatic and ampullary tumor. Diagnostic laparoscopy was performed on 20 patients included in the study Mean age was 58.35 +/- 13.4 years. Twelve were males and eight females. In two patients, laparoscopy showed peritoneal metastases and ultrasound did not show extrapancreatic involvement. In five patients, there was vascular invasion without metastases. In three patients, both peritoneal metastases and vascular invasion were found, and in five there was neither vascular invasion nor metastasis. Laparoscopic findings were confirmed in a but one patient. In 14 of the 16 patients In whom peritoneal lavage was performed, microscopic exam showed a sufficient number of cells to make a diagnosis. We concluded that laparoscopy with ultrasound is useful in staging of patients with duodeno-bilio-pancreatic malignancies. 相似文献
102.
Monari C Retini C Casadevall A Netski D Bistoni F Kozel TR Vecchiarelli A 《European journal of immunology》2003,33(4):1041-1051
Disseminated infections by the opportunistic yeast Cryptococcus neoformans are characterized by accumulation in tissues of glucuronoxylomannan (GXM), the major component of the capsular polysaccharide. We investigated binding, uptake, and disposal of GXM by peripheral blood neutrophils and monocytes, and the effect of GXM uptake on phagocytic cell function. GXM was efficiently bound and internalized by both types of phagocytic cells, with maximal loading at 50 microg/ml, a GXM concentration found in serum and cerebrospinal fluid of some cryptococcosis patients. However, substantial differences were noted in the kinetics for uptake by macrophages and neutrophils. Whereas neutrophils rapidly ingested limited amounts of GXM and then expelled or degraded it after 1 h of incubation, macrophages demonstrated continuous intracellular accumulation for up to 1 week of incubation. Accumulation of GXM by neutrophils was accompanied by reduced anticryptococcal activity, suggesting one more mechanism for virulence enhancement by the major capsular component of C. neoformans. 相似文献
103.
It has been recently observed that MYB proteins are induced in neuronal cell cultures exposed to DNA damaging agents or growth factor deprivation. While it has been proposed that MYB proteins activity is required to bring about death in neuronal cells subjected to apoptotic stimuli, here we show that MYB is not activated in differentiated pheochromocytoma-12 cells (PC12) or LAN5 cells exposed to the DNA damaging agent campothecin or in differentiated PC12 cells subjected to nerve growth factor withdrawal. We conclude that MYB activation cannot be generalised in terminally differentiated neuronal cancer cell lines. 相似文献
104.
Rocio Ramos‐Medina Aurea García‐Segovia Juana Gil Javier Carbone Angel Aguarón de la Cruz Ansgar Seyfferth Bárbara Alonso Jorge Alonso Juan A. León Diana Alecsandru Elena Meliá Elena Carrillo de Albornoz Daniel Ordoñez Isabel Santillán Victoria Verdú Jose Maria Garcia Ruiz de Morales Marcos López‐Hoyos Arturo López Larios Almudena Sampalo Pedro Caballero Luis Ortiz Quintana Eduardo Fernández‐Cruz Silvia Sánchez‐Ramón 《American journal of reproductive immunology (New York, N.Y. : 1989)》2014,71(5):458-466
105.
106.
Prognostic impact of chromosomal translocations in myelodysplastic syndromes and chronic myelomonocytic leukemia patients. A study by the spanish group of myelodysplastic syndromes 下载免费PDF全文
Meritxell Nomdedeu Xavier Calvo Arturo Pereira Anna Carri Francesc Sol Elisa Luo Jos Cervera Teresa Vallespí Concha Muoz Cndida Gmez Amparo Arias Esperanza Such Guillermo Sanz Javier Grau Andrs Insunza María‐Jos Calasanz María‐Teresa Ardanaz Jesús‐María Hernndez‐Rivas Gemma Azaceta Sara lvarez Joaquín Snchez María‐Luisa Martín Joan Bargay Valle Gmez Carlos‐Javier Cervero María‐Jos Allegue Rosa Collado Elías Campo Jordi Esteve Benet Nomdedeu Dolors Costa 《Genes, chromosomes & cancer》2016,55(4):322-327
Chromosomal translocations are rare in the myelodysplastic syndromes (MDS) and chronic myelomonocytic leukemia (CMML). With the exception of t(3q), translocations are not explicitly considered in the cytogenetic classification of the IPSS‐R and their impact on disease progression and patient survival is unknown. The present study was aimed at determining the prognostic impact of translocations in the context of the cytogenetic classification of the IPSS‐R. We evaluated 1,653 patients from the Spanish Registry of MDS diagnosed with MDS or CMML and an abnormal karyotype by conventional cytogenetic analysis. Translocations were identified in 168 patients (T group). Compared with the 1,485 patients with abnormal karyotype without translocations (non‐T group), the T group had a larger proportion of patients with refractory anemia with excess of blasts and higher scores in both the cytogenetic and global IPSS‐R. Translocations were associated with a significantly shorter survival and higher incidence of transformation into AML at univariate analysis but both features disapeared after multivariate adjustment for the IPSS‐R cytogenetic category. Patients with single or double translocations other than t(3q) had an outcome similar to those in the non‐T group in the intermediate cytogenetic risk category of the IPSS‐R. In conclusion, the presence of translocations identifies a subgroup of MDS/CMML patients with a more aggressive clinical presentation that can be explained by a higher incidence of complex karyotypes. Single or double translocations other than t(3q) should be explicitly considered into the intermediate risk category of cytogenetic IPSS‐R classification. © 2015 Wiley Periodicals, Inc. 相似文献
107.
Cryptococcus neoformans, an encapsulated yeast, is a common cause of life-threatening meningoencephalitis in immunosuppressed patients. We previously observed that administration of a monoclonal antibody (MAb) to the capsular polysaccharide to mice with pulmonary infection prolonged survival and enhanced granulomatous inflammation without reducing lung CFU. To understand the mechanism of MAb action, we studied leukocyte recruitment and cytokine profiles in lungs of A/JCr mice. B lymphocytes were the predominant cell type in lung infiltrates, comprising 15 to 30% of the leukocytes. Despite alterations in histological appearance, fluorescence-activated cell sorter analysis revealed no significant difference in total numbers of lung leukocytes in MAb-treated mice and controls. Differences in the immune response to C. neoformans between MAb-treated mice and controls included (i) an increase in the percentage of granulocytes among lung leukocytes on day 14, (ii) higher macrophage surface expression of CD86 on day 28, (iii) larger amounts of IL-10 in lung homogenates at day 7, (iv) a trend toward smaller amounts of gamma interferon mRNA and protein on day 7, and (v) a smaller increase in the levels of interleukin-4 mRNA and protein on day 7. Hence, the immune responses to C. neoformans infection in the presence and absence of specific antibody were qualitatively similar, and antibody administration was associated with several subtle quantitative differences in immune response parameters that could translate into enhanced survival. MAb may function partly by down-regulating the inflammatory response and reducing host damage. Our findings demonstrate unexpected complexity in the interaction between specific MAb and other components of the host immune response. 相似文献
108.
Varadharaj S Watkins T Cardounel AJ Garcia JG Zweier JL Kuppusamy P Natarajan V Parinandi NL 《Antioxidants & redox signaling》2005,7(1-2):287-300
Recent clinical trials have shown that vitamin C, at pharmacological concentrations (milligram to approximately gram), upon infusion into circulation, modulates vasodilation and vascular tone in humans. This also results in the elevated concentrations of vitamin C in circulation in the millimolar range. Here, it was hypothesized that vitamin C at pharmacological concentrations (millimolar) would induce oxidative stress and cause loss of redox-dependent cell viability in vascular endothelial cells (ECs). To test the hypothesis, bovine lung microvascular ECs (BLMVECs) in monolayer cultures were exposed to vitamin C (0-10 mM) for different time periods (0-2 h). Electron paramagnetic resonance spectroscopy revealed the intracellular formation of ascorbate free radical in a dose- and time-dependent fashion. Vitamin C also induced formation of intracellular reactive oxygen species in a dose-dependent fashion. It was observed that vitamin C induced morphological alterations and loss of cell viability in a dose- and time-dependent fashion, as measured by light microscopy and Alamar Blue redox cell viability assay, respectively. Vitamin C analogues failed to induce such changes. Vitamin C depleted cellular GSH levels in a dose-dependent fashion, suggesting that vitamin C altered thiol-redox status in BLMVECs. Antioxidants, intracellular iron chelator, and catalase protected cells against vitamin C-induced loss of redox-dependent cell viability, confirming the role of hydrogen peroxide and iron during redox cycling of vitamin C. These results, for the first time in detail, established that vitamin C at pharmacological doses induced oxidative stress and loss of redox-dependent cell viability in microvascular ECs. 相似文献
109.
Molina MC Ferreira V Valck C Aguilar L Orellana J Rojas A Ramirez G Billetta R Schwaeble W Lemus D Ferreira A 《Molecular and biochemical parasitology》2005,140(2):133-140
Angiogenesis leads to neovascularization from existing blood vessels. It is associated with tumor growth and metastasis and is regulated by pro- and antiangiogenic molecules, some of them currently under clinical trials for cancer treatment. During the last few years we have cloned, sequenced and expressed a Trypanosoma cruzi calreticulin gene (TcCRT). Its product, TcCRT, a 45 kDa protein, is more than 50% identical to human CRT (HuCRT). TcCRT, present on the surface of trypomastigotes, binds both C1q and mannan binding lectin and inhibits the classical activation pathway of human complement. Since TcCRT is highly homologous to a functional antiangiogenic fragment from HuCRT (aa 120–180), recombinant (r) and native (n) TcCRT were tested in their antiangiogenic effects, in the chick embryonic chorioallantoid membrane (CAM) assay. Both proteins mediated highly significant antiangiogenic effects in the in vivo CAM assay. This effect was further substantiated in experiments showing that the plasmid construct pSecTag/TcCRT also displayed significant antiangiogenic properties, as compared to the empty vector. Most likely, the fact that antiangiogenic substances act preferentially on growing neoplasic tissues, but not on already established tumors, is due to their effects on emerging blood vessels. The results shown here indicate that TcCRT, like its human counterpart, has antiangiogenic properties. These properties may explain, at least partly, the reported antineoplasic effect of experimental T. cruzi infection. 相似文献
110.
Emilio Domínguez‐Salazar Gabriela Hurtado‐Alvarado Fernanda Medina‐Flores Javik Dorantes Oscar Gonzlez‐Flores Arturo Contis‐Montes de Oca Javier Velzquez‐Moctezuma Beatriz Gmez‐Gonzlez 《Journal of sleep research》2020,29(3)
Sleep loss increases blood–brain barrier permeability. As the blood–brain barrier and the blood–tissue barriers in the reproductive tract (blood–testis and blood–epididymis barriers) share common characteristics, we hypothesized that sleep restriction may also modify their barrier function. Previous reports showed that sleep loss decreased sperm viability and progressive fast mobility, which may be a consequence of altered blood–testis and blood–epididymis barrier. Therefore, we quantified changes in blood–testis and blood–epididymis barrier after sleep loss and related them to male fertility. Adult male Wistar rats were sleep restricted using the multiple‐platform technique in a protocol of 20 hr daily sleep deprivation plus 4 hr of sleep recovery in the home‐cage. At the 10th day, barrier permeability assays were performed with Na‐fluorescein, 10 kDa Cascade blue‐dextrans and Evans blue, and the expression of tight junction proteins, actin and androgen receptor was quantified. At the 10th day of sleep restriction and after sleep recovery days 1–7, males were placed with sexually receptive females, sexual behaviour was tested, and the percentage of pregnancies was calculated. Sleep restriction increased the barrier permeability to low‐ and high‐molecular‐weight tracers, and decreased the expression of tight junction proteins, actin and androgen receptor. Concomitantly, sleep restriction reduced the percentage of ejaculating males and the number of pregnancies. Sleep recovery for 2–3 days progressively re‐established fertility, as indicated by a higher percentage of ejaculating males and impregnated females. In conclusion, chronic sleep loss alters fertility concomitantly with the disruption of the blood–tissue barriers at the reproductive tract, the mechanism involves androgen signalling. 相似文献