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53.
Renal toxicity has become an important issue in HIV-infected patients receiving highly active antiretroviral therapy (HAART). Several biomarkers are available for monitoring renal function, although no consensus exists on how best to apply these tools in HIV infection. The best biomarker is the glomerular filtration rate (GFR), and several creatinine-based estimates equations of GFR are widely used in HIV infection, with clinical advantages for the equation developed by Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI). Although serum cystatin C has been proposed as a more sensitive marker of renal dysfunction in HIV infection, it may be affected by ongoing inflammation. Tubular dysfunction can be simple or complex, depending on whether the tubular transport of one or more substances is affected. Multiple renal tubular dysfunction or Fanconi syndrome is characterized by alterations in the reabsorption of glucose, amino acids, phosphate and often also bicarbonate. Therefore, Fanconi syndrome would be the tip of the iceberg, and the most unusual and severe manifestation. In the last years, several low molecular weight proteins as markers of tubular alteration, including retinol-binding protein, b2-microglobulin, and neutrophil gelatinase associated lipocalin have become available. Different studies have shown differences in urine concentrations of these proteins in patients receiving tenofovir, but again, no consistent data have shown their clinical usefulness in predicting the clinical consequences of tubular alteration. Thus, we review findings from recent studies performed in this area to describe the performance of new biomarkers for renal damage in HIV-infected patients. 相似文献
54.
Liesegang rings are uncommon pathological findings which may cause diagnostic dilemmas for pathologists. Awareness of their appearance is important to avoid over diagnosis of parasitic infection, algal contamination and psammoma bodies. Liesegang rings are benign, lamellar structures with radial striations and a central amorphous core. They are found in a variety of tissues and fluids in both an intra- and extra-cellular sites. We present here a case of a cystic renal lesion containing Liesegang rings mimicking a renal cell carcinoma.Key Words: Liesegang rings, Kidney, Pseudotumor 相似文献
55.
Cytokine activation during attacks of the hyperimmunoglobulinemia D and periodic fever syndrome 总被引:9,自引:0,他引:9
Drenth JP; van Deuren M; van der Ven-Jongekrijg J; Schalkwijk CG; van der Meer JW 《Blood》1995,85(12):3586-3593
The hyperimmunoglobulinemia D and periodic fever (hyper-IgD) syndrome is typified by recurrent febrile attacks with abdominal distress, joint involvement (arthralgias/arthritis), headache, skin lesions, and an elevated serum IgD level (> 100 U/mL). This familial disorder has been diagnosed in 59 patients, mainly from Europe. The pathogenesis of this febrile disorder is unknown, but attacks are joined by an acute-phase response. Because this response is considered to be mediated by cytokines, we measured the acute-phase proteins C-reactive protein (CRP) and soluble type-II phospholipase A2 (PLA2) together with circulating concentrations and ex vivo production of the proinflammatory cytokines interleukin-1 alpha (IL-1 alpha), IL-1 beta, IL-6, and tumor necrosis factor alpha (TNF alpha) and the inhibitory compounds IL-1 receptor antagonist (IL-1ra), IL-10, and the soluble TNF receptors p55 (sTNFr p55) and p75 (sTNFr p75) in 22 patients with the hyper-IgD syndrome during attacks and remission. Serum CRP and PLA2 concentrations were elevated during attacks (mean, 213 mg/L and 1,452 ng/mL, respectively) and decreased between attacks. Plasma concentrations of IL-1 alpha, IL-1 beta, or IL-10 were not increased during attacks. TNF alpha concentrations were slightly, but significantly, higher with attacks (104 v 117 pg/mL). Circulating IL-6 values increased with attacks (19.7 v 147.9 pg/mL) and correlated with CRP and PLA2 values during the febrile attacks. The values of the antiinflammatory compounds IL-1ra, sTNFr p55, and sTNFr p75 were significantly higher with attacks than between attacks, and there was a significant positive correlation between each. The ex-vivo production of TNF alpha, IL-1 beta, and IL-1ra was significantly higher with attacks, suggesting that the monocytes/macrophages were already primed in vivo to produce increased amounts of these cytokines. These findings point to an activation of the cytokine network, and this suggests that these inflammatory mediators may contribute to the symptoms of the hyper-IgD syndrome. 相似文献
56.
Cicuttini FM; Martin M; Salvaris E; Ashman L; Begley CG; Novotny J; Maher D; Boyd AW 《Blood》1992,80(1):102-112
We describe the development of a human bone marrow (BM) culture system which allows study of the interaction of stromal cell lines (SCL) and highly purified hematopoietic progenitor cells. Normal BM stromal cells were electroporated with a plasmid containing the simian virus 40 (SV40) large T antigen (SV40 T Ag) under the control of a synthetic metallothionein promoter (MT4); this construct is designated MT4 SV40 T Ag. SCL in which the rate of proliferation could be controlled by altering the zinc (Zn) concentration were characterized, demonstrating that the SCL were heterogeneous with respect to G-CSF and GM-CSF production. Suppression of SCL proliferation on removal of Zn made it possible to use these lines in coculture with purified CD34+ progenitor cells from umbilical cord blood. The ability to control proliferation of SCL has allowed us to maintain the survival and expansion of colony- forming cells in culture for up to 2 months. These lines have enabled us to test for stromal cell characteristics at a clonal level and provided us with a tool to analyze the events leading to lineage commitment and hematopoietic differentiation, as demonstrated by suppression of hematopoiesis by an antibody directed against the c-kit molecule. 相似文献
57.
O'Malley CJ; Rasko JE; Basser RL; McGrath KM; Cebon J; Grigg AP; Hopkins W; Cohen B; O'Byrne J; Green MD; Fox RM; Berndt MC; Begley CG 《Blood》1996,88(9):3288-3298
This report describes the effect of pegylated recombinant human megakaryocyte growth and development factor (PEG-rHuMGDF) on platelet production and platelet function in humans. Subjects with advanced solid tumors received PEG-rHuMGDF daily for up to 10 days. There was no increase in circulating platelet count at doses of 0.03 or 0.1 microgram/kg/d by day 12 of study. At doses of 0.3 and 1.0 microgram/kg/d there was a threefold median increase (maximum 10-fold) in platelet count by day 16. The platelets produced in vivo in response to PEG-rHuMGDF showed unchanged aggregation and adenosine triphosphate (ATP)-release responses in in vitro assays. Tests included aggregation and release of ATP in response to adenosine diphosphate (ADP) (10, 5, 2.5, and 1.25 mumol/L), collagen (2 micrograms/mL), thrombin-receptor agonist peptide (TRAP, 10 mumol/L) and ristocetin (1.5 mg/mL). Administration of aspirin to an individual with platelet count of 1,771 x 10(3)/L resulted in the typical aspirin-induced ablation of the normal aggregation and ATP-release response to stimulation with arachidonic acid (0.5 mg/mL), collagen, and ADP (2.5 and 1.25 mumol/L). There was no change in the expression of the platelet-surface activation marker CD62P (P-selectin) nor induction of the fibrinogen binding site on glycoprotein IIb/IIIa as reported by the monoclonal antibody, D3GP3. An elevation of reticulated platelets was evident after 3 days of treatment with PEG-rHuMGDF and preceded the increase in circulating platelet count by 5 to 8 days; this reflected the production of new platelets in response to PEG-rHuMGDF. At later time points, the mean platelet volume (MPV) decreased in a manner inversely proportional to the platelet count. Levels of plasma glycocalicin, a measure of platelet turnover, rose 3 days after the initial increase in the peripheral platelet count. The level of plasma glycocalicin was proportional to the total platelet mass, suggesting that platelets generated in response to PEG-rHuMGDF were not more actively destroyed. Thus, the administration of PEG-rHuMGDF, to humans, increased the circulating platelet count and resulted in fully functional platelets, which showed no detectable increase in reactivity nor alteration in activation status. 相似文献
58.
Aitziber Aguinaga Jorge Díaz-González Alejandra Pérez-García Laura Barrado Iván Martínez-Baz Itziar Casado Regina Juanbeltz Carmen Ezpeleta Jesús Castilla 《Enfermedades infecciosas y microbiología clínica》2018,36(6):325-331
Objective
To estimate the prevalence of hepatitis C virus (HCV) infection in Navarra, Spain, as well as to distinguish between diagnosed and undiagnosed infections.Methods
A study was conducted on patients scheduled for surgery unrelated to HCV infection. They were all tested for HCV antibodies, under a routine scheme, from January 2014 to September 2016. Patients with a positive result by enzyme immunoassay were confirmed using immunoblot and/or HCV-RNA. Previous laboratory results were also taken into account. The prevalence was adjusted to the sex and age structure of the Navarra population.Results
The study included a total of 7,378 patients with a median age 46 years, of whom 50% women. HCV antibodies were detected in 69 patients, which is a prevalence in the population of 0.83% (95% confidence interval: 0.64-1.05), and was higher in men (1.11%) than in women (0.56%; P = .0102). Among the HCV positive patients, 67 (97%) had had another previous positive result. Population prevalence of previous positive HCV was 0.80%, and was 0.03% for a new diagnosis. Of the HCV positive patients, 78% had detectable HCV-RNA. It was estimated that 0.65% of the population had had detectable HCV-RNA, and 0.51% continued to have it when recruited into the study.Conclusion
Previous estimates of prevalence of HCV infection should be revised downwards. Only a small proportion of HCV positive patients remain undiagnosed, and only a small part have active infection. 相似文献59.
Leticia Leon Lydia Abasolo Marta Redondo Miguel Angel Perez-Nieto Luis Rodriguez-Rodriguez Maria Isabel Casado Rafael Curbelo Juan Ángel Jover 《Rheumatology international》2014,34(5):597-604
Negative affect appears frequently in rheumatic diseases, but studies about their importance and prevalence in systemic sclerosis patients are scarce, and the results are inconclusive separately. We conducted a comprehensive search on April 2013 of PubMed, Medline, and PsycINFO databases to identify original research studies published. A total of 48 studies were included in this systematic review. We found negative emotions have very high levels in these patients, compared to both healthy population other chronic rheumatic patients assessed with the same instruments and cutoffs. Depression has been, of the three negative emotions that we approach to in this review, the most widely studied in systemic sclerosis, followed by anxiety. Despite the fact that anger is a common emotion in these diseases is poorly studied. Methodologic issues limited the ability to draw strong conclusions from studies of predictors. Disease-specific symptoms (swollen joints, gastrointestinal and respiratory symptoms and digital ulcers) and factors related to physical appearance were associated with negative emotions. Interdisciplinary care and biopsychosocial approach would have a great benefit in the clinical management of these patients. 相似文献
60.
Esteban Martínez Esteban Jódar Gimeno Rebeca Reyes García Pedro Carpintero José Luis Casado Javier del Pino Montes Pere Domingo Pedrol Vicente Estrada Jorge Maalouf Eugenia Negredo Antonio Ocampo Manuel Muñoz-Torres 《Enfermedades infecciosas y microbiología clínica》2014